The Tor Browser: gfx/thebes/gfxFont.cpp@97036ab72558 (annotated)

gfx/thebes/gfxFont.cpp@97036ab72558 (annotated)

gfx/thebes/gfxFont.cpp

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rw-r--r--

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 #include "mozilla/DebugOnly.h"
 #include "mozilla/MathAlgorithms.h"
 #ifdef MOZ_LOGGING
 #define FORCE_PR_LOG /* Allow logging in the release build */
 #endif
 #include "prlog.h"
 #include "nsServiceManagerUtils.h"
 #include "nsExpirationTracker.h"
 #include "nsILanguageAtomService.h"
 #include "nsITimer.h"
 #include "gfxFont.h"
 #include "gfxPlatform.h"
 #include "nsGkAtoms.h"
 #include "gfxTypes.h"
 #include "gfxContext.h"
 #include "gfxFontMissingGlyphs.h"
 #include "gfxHarfBuzzShaper.h"
 #include "gfxUserFontSet.h"
 #include "gfxPlatformFontList.h"
 #include "gfxScriptItemizer.h"
 #include "nsUnicodeProperties.h"
 #include "nsMathUtils.h"
 #include "nsBidiUtils.h"
 #include "nsUnicodeRange.h"
 #include "nsStyleConsts.h"
 #include "mozilla/FloatingPoint.h"
 #include "mozilla/Likely.h"
 #include "mozilla/MemoryReporting.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/Services.h"
 #include "mozilla/Telemetry.h"
 #include "gfxSVGGlyphs.h"
 #include "gfxMathTable.h"
 #include "gfx2DGlue.h"
 #if defined(XP_MACOSX)
 #include "nsCocoaFeatures.h"
 #endif
 #include "cairo.h"
 #include "gfxFontTest.h"
 #include "harfbuzz/hb.h"
 #include "harfbuzz/hb-ot.h"
 #include "graphite2/Font.h"
 #include "nsCRT.h"
 #include "GeckoProfiler.h"
 #include "gfxFontConstants.h"
 #include <algorithm>
 using namespace mozilla;
 using namespace mozilla::gfx;
 using namespace mozilla::unicode;
 using mozilla::services::GetObserverService;
 gfxFontCache *gfxFontCache::gGlobalCache = nullptr;
 static const char16_t kEllipsisChar[] = { 0x2026, 0x0 };
 static const char16_t kASCIIPeriodsChar[] = { '.', '.', '.', 0x0 };
 #ifdef DEBUG_roc
 #define DEBUG_TEXT_RUN_STORAGE_METRICS
 #endif
 #ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
 static uint32_t gTextRunStorageHighWaterMark = 0;
 static uint32_t gTextRunStorage = 0;
 static uint32_t gFontCount = 0;
 static uint32_t gGlyphExtentsCount = 0;
 static uint32_t gGlyphExtentsWidthsTotalSize = 0;
 static uint32_t gGlyphExtentsSetupEagerSimple = 0;
 static uint32_t gGlyphExtentsSetupEagerTight = 0;
 static uint32_t gGlyphExtentsSetupLazyTight = 0;
 static uint32_t gGlyphExtentsSetupFallBackToTight = 0;
 #endif
 #ifdef PR_LOGGING
 #define LOG_FONTINIT(args) PR_LOG(gfxPlatform::GetLog(eGfxLog_fontinit), \
                                   PR_LOG_DEBUG, args)
 #define LOG_FONTINIT_ENABLED() PR_LOG_TEST( \
                                         gfxPlatform::GetLog(eGfxLog_fontinit), \
                                         PR_LOG_DEBUG)
 #endif // PR_LOGGING
 void
 gfxCharacterMap::NotifyReleased()
 {
     gfxPlatformFontList *fontlist = gfxPlatformFontList::PlatformFontList();
     if (mShared) {
         fontlist->RemoveCmap(this);
     }
     delete this;
 }
 gfxFontEntry::gfxFontEntry() :
     mItalic(false), mFixedPitch(false),
     mIsProxy(false), mIsValid(true),
     mIsBadUnderlineFont(false),
     mIsUserFont(false),
     mIsLocalUserFont(false),
     mStandardFace(false),
     mSymbolFont(false),
     mIgnoreGDEF(false),
     mIgnoreGSUB(false),
     mSVGInitialized(false),
     mMathInitialized(false),
     mHasSpaceFeaturesInitialized(false),
     mHasSpaceFeatures(false),
     mHasSpaceFeaturesKerning(false),
     mHasSpaceFeaturesNonKerning(false),
     mSkipDefaultFeatureSpaceCheck(false),
     mCheckedForGraphiteTables(false),
     mHasCmapTable(false),
     mGrFaceInitialized(false),
     mWeight(500), mStretch(NS_FONT_STRETCH_NORMAL),
     mUVSOffset(0), mUVSData(nullptr),
     mLanguageOverride(NO_FONT_LANGUAGE_OVERRIDE),
     mUnitsPerEm(0),
     mHBFace(nullptr),
     mGrFace(nullptr),
     mGrFaceRefCnt(0)
 {
     memset(&mDefaultSubSpaceFeatures, 0, sizeof(mDefaultSubSpaceFeatures));
     memset(&mNonDefaultSubSpaceFeatures, 0, sizeof(mNonDefaultSubSpaceFeatures));
 }
 gfxFontEntry::gfxFontEntry(const nsAString& aName, bool aIsStandardFace) :
     mName(aName), mItalic(false), mFixedPitch(false),
     mIsProxy(false), mIsValid(true),
     mIsBadUnderlineFont(false), mIsUserFont(false),
     mIsLocalUserFont(false), mStandardFace(aIsStandardFace),
     mSymbolFont(false),
     mIgnoreGDEF(false),
     mIgnoreGSUB(false),
     mSVGInitialized(false),
     mMathInitialized(false),
     mHasSpaceFeaturesInitialized(false),
     mHasSpaceFeatures(false),
     mHasSpaceFeaturesKerning(false),
     mHasSpaceFeaturesNonKerning(false),
     mSkipDefaultFeatureSpaceCheck(false),
     mCheckedForGraphiteTables(false),
     mHasCmapTable(false),
     mGrFaceInitialized(false),
     mWeight(500), mStretch(NS_FONT_STRETCH_NORMAL),
     mUVSOffset(0), mUVSData(nullptr),
     mLanguageOverride(NO_FONT_LANGUAGE_OVERRIDE),
     mUnitsPerEm(0),
     mHBFace(nullptr),
     mGrFace(nullptr),
     mGrFaceRefCnt(0)
 {
     memset(&mDefaultSubSpaceFeatures, 0, sizeof(mDefaultSubSpaceFeatures));
     memset(&mNonDefaultSubSpaceFeatures, 0, sizeof(mNonDefaultSubSpaceFeatures));
 }
 gfxFontEntry::~gfxFontEntry()
 {
     // For downloaded fonts, we need to tell the user font cache that this
     // entry is being deleted.
     if (!mIsProxy && IsUserFont() && !IsLocalUserFont()) {
         gfxUserFontSet::UserFontCache::ForgetFont(this);
     }
     // By the time the entry is destroyed, all font instances that were
     // using it should already have been deleted, and so the HB and/or Gr
     // face objects should have been released.
     MOZ_ASSERT(!mHBFace);
     MOZ_ASSERT(!mGrFaceInitialized);
 }
 bool gfxFontEntry::IsSymbolFont()
 {
     return mSymbolFont;
 }
 bool gfxFontEntry::TestCharacterMap(uint32_t aCh)
 {
     if (!mCharacterMap) {
         ReadCMAP();
         NS_ASSERTION(mCharacterMap, "failed to initialize character map");
     }
     return mCharacterMap->test(aCh);
 }
 nsresult gfxFontEntry::InitializeUVSMap()
 {
     // mUVSOffset will not be initialized
     // until cmap is initialized.
     if (!mCharacterMap) {
         ReadCMAP();
         NS_ASSERTION(mCharacterMap, "failed to initialize character map");
     }
     if (!mUVSOffset) {
         return NS_ERROR_FAILURE;
     }
     if (!mUVSData) {
         const uint32_t kCmapTag = TRUETYPE_TAG('c','m','a','p');
         AutoTable cmapTable(this, kCmapTag);
         if (!cmapTable) {
             mUVSOffset = 0; // don't bother to read the table again
             return NS_ERROR_FAILURE;
         }
         uint8_t* uvsData;
         unsigned int cmapLen;
         const char* cmapData = hb_blob_get_data(cmapTable, &cmapLen);
         nsresult rv = gfxFontUtils::ReadCMAPTableFormat14(
                           (const uint8_t*)cmapData + mUVSOffset,
                           cmapLen - mUVSOffset, uvsData);
         if (NS_FAILED(rv)) {
             mUVSOffset = 0; // don't bother to read the table again
             return rv;
         }
         mUVSData = uvsData;
     }
     return NS_OK;
 }
 uint16_t gfxFontEntry::GetUVSGlyph(uint32_t aCh, uint32_t aVS)
 {
     InitializeUVSMap();
     if (mUVSData) {
         return gfxFontUtils::MapUVSToGlyphFormat14(mUVSData, aCh, aVS);
     }
     return 0;
 }
 bool gfxFontEntry::SupportsScriptInGSUB(const hb_tag_t* aScriptTags)
 {
     hb_face_t *face = GetHBFace();
     if (!face) {
         return false;
     }
     unsigned int index;
     hb_tag_t     chosenScript;
     bool found =
         hb_ot_layout_table_choose_script(face, TRUETYPE_TAG('G','S','U','B'),
                                          aScriptTags, &index, &chosenScript);
     hb_face_destroy(face);
     return found && chosenScript != TRUETYPE_TAG('D','F','L','T');
 }
 nsresult gfxFontEntry::ReadCMAP(FontInfoData *aFontInfoData)
 {
     NS_ASSERTION(false, "using default no-op implementation of ReadCMAP");
     mCharacterMap = new gfxCharacterMap();
     return NS_OK;
 }
 nsString
 gfxFontEntry::RealFaceName()
 {
     AutoTable nameTable(this, TRUETYPE_TAG('n','a','m','e'));
     if (nameTable) {
         nsAutoString name;
         nsresult rv = gfxFontUtils::GetFullNameFromTable(nameTable, name);
         if (NS_SUCCEEDED(rv)) {
             return name;
         }
     }
     return Name();
 }
 already_AddRefed<gfxFont>
 gfxFontEntry::FindOrMakeFont(const gfxFontStyle *aStyle, bool aNeedsBold)
 {
     // the font entry name is the psname, not the family name
     nsRefPtr<gfxFont> font = gfxFontCache::GetCache()->Lookup(this, aStyle);
     if (!font) {
         gfxFont *newFont = CreateFontInstance(aStyle, aNeedsBold);
         if (!newFont)
             return nullptr;
         if (!newFont->Valid()) {
             delete newFont;
             return nullptr;
         }
         font = newFont;
         gfxFontCache::GetCache()->AddNew(font);
     }
     return font.forget();
 }
 uint16_t
 gfxFontEntry::UnitsPerEm()
 {
     if (!mUnitsPerEm) {
         AutoTable headTable(this, TRUETYPE_TAG('h','e','a','d'));
         if (headTable) {
             uint32_t len;
             const HeadTable* head =
                 reinterpret_cast<const HeadTable*>(hb_blob_get_data(headTable,
                                                                     &len));
             if (len >= sizeof(HeadTable)) {
                 mUnitsPerEm = head->unitsPerEm;
             }
         }
         // if we didn't find a usable 'head' table, or if the value was
         // outside the valid range, record it as invalid
         if (mUnitsPerEm < kMinUPEM || mUnitsPerEm > kMaxUPEM) {
             mUnitsPerEm = kInvalidUPEM;
         }
     }
     return mUnitsPerEm;
 }
 bool
 gfxFontEntry::HasSVGGlyph(uint32_t aGlyphId)
 {
     NS_ASSERTION(mSVGInitialized, "SVG data has not yet been loaded. TryGetSVGData() first.");
     return mSVGGlyphs->HasSVGGlyph(aGlyphId);
 }
 bool
 gfxFontEntry::GetSVGGlyphExtents(gfxContext *aContext, uint32_t aGlyphId,
                                  gfxRect *aResult)
 {
     NS_ABORT_IF_FALSE(mSVGInitialized,
                       "SVG data has not yet been loaded. TryGetSVGData() first.");
     NS_ABORT_IF_FALSE(mUnitsPerEm >= kMinUPEM && mUnitsPerEm <= kMaxUPEM,
                       "font has invalid unitsPerEm");
     gfxContextAutoSaveRestore matrixRestore(aContext);
     cairo_matrix_t fontMatrix;
     cairo_get_font_matrix(aContext->GetCairo(), &fontMatrix);
     gfxMatrix svgToAppSpace = *reinterpret_cast<gfxMatrix*>(&fontMatrix);
     svgToAppSpace.Scale(1.0f / mUnitsPerEm, 1.0f / mUnitsPerEm);
     return mSVGGlyphs->GetGlyphExtents(aGlyphId, svgToAppSpace, aResult);
 }
 bool
 gfxFontEntry::RenderSVGGlyph(gfxContext *aContext, uint32_t aGlyphId,
                              int aDrawMode, gfxTextContextPaint *aContextPaint)
 {
     NS_ASSERTION(mSVGInitialized, "SVG data has not yet been loaded. TryGetSVGData() first.");
     return mSVGGlyphs->RenderGlyph(aContext, aGlyphId, DrawMode(aDrawMode),
                                    aContextPaint);
 }
 bool
 gfxFontEntry::TryGetSVGData(gfxFont* aFont)
 {
     if (!gfxPlatform::GetPlatform()->OpenTypeSVGEnabled()) {
         return false;
     }
     if (!mSVGInitialized) {
         mSVGInitialized = true;
         // If UnitsPerEm is not known/valid, we can't use SVG glyphs
         if (UnitsPerEm() == kInvalidUPEM) {
             return false;
         }
         // We don't use AutoTable here because we'll pass ownership of this
         // blob to the gfxSVGGlyphs, once we've confirmed the table exists
         hb_blob_t *svgTable = GetFontTable(TRUETYPE_TAG('S','V','G',' '));
         if (!svgTable) {
             return false;
         }
         // gfxSVGGlyphs will hb_blob_destroy() the table when it is finished
         // with it.
         mSVGGlyphs = new gfxSVGGlyphs(svgTable, this);
     }
     if (!mFontsUsingSVGGlyphs.Contains(aFont)) {
         mFontsUsingSVGGlyphs.AppendElement(aFont);
     }
     return !!mSVGGlyphs;
 }
 void
 gfxFontEntry::NotifyFontDestroyed(gfxFont* aFont)
 {
     mFontsUsingSVGGlyphs.RemoveElement(aFont);
 }
 void
 gfxFontEntry::NotifyGlyphsChanged()
 {
     for (uint32_t i = 0, count = mFontsUsingSVGGlyphs.Length(); i < count; ++i) {
         gfxFont* font = mFontsUsingSVGGlyphs[i];
         font->NotifyGlyphsChanged();
     }
 }
 bool
 gfxFontEntry::TryGetMathTable(gfxFont* aFont)
 {
     if (!mMathInitialized) {
         mMathInitialized = true;
         // If UnitsPerEm is not known/valid, we can't use MATH table
         if (UnitsPerEm() == kInvalidUPEM) {
             return false;
         }
         // We don't use AutoTable here because we'll pass ownership of this
         // blob to the gfxMathTable, once we've confirmed the table exists
         hb_blob_t *mathTable = GetFontTable(TRUETYPE_TAG('M','A','T','H'));
         if (!mathTable) {
             return false;
         }
         // gfxMathTable will hb_blob_destroy() the table when it is finished
         // with it.
         mMathTable = new gfxMathTable(mathTable);
         if (!mMathTable->HasValidHeaders()) {
             mMathTable = nullptr;
             return false;
         }
     }
     return !!mMathTable;
 }
 gfxFloat
 gfxFontEntry::GetMathConstant(gfxFontEntry::MathConstant aConstant)
 {
     NS_ASSERTION(mMathTable, "Math data has not yet been loaded. TryGetMathData() first.");
     gfxFloat value = mMathTable->GetMathConstant(aConstant);
     if (aConstant == gfxFontEntry::ScriptPercentScaleDown ||
         aConstant == gfxFontEntry::ScriptScriptPercentScaleDown ||
         aConstant == gfxFontEntry::RadicalDegreeBottomRaisePercent) {
         return value / 100.0;
     }
     return value / mUnitsPerEm;
 }
 bool
 gfxFontEntry::GetMathItalicsCorrection(uint32_t aGlyphID,
                                        gfxFloat* aItalicCorrection)
 {
     NS_ASSERTION(mMathTable, "Math data has not yet been loaded. TryGetMathData() first.");
     int16_t italicCorrection;
     if (!mMathTable->GetMathItalicsCorrection(aGlyphID, &italicCorrection)) {
         return false;
     }
     *aItalicCorrection = gfxFloat(italicCorrection) / mUnitsPerEm;
     return true;
 }
 uint32_t
 gfxFontEntry::GetMathVariantsSize(uint32_t aGlyphID, bool aVertical,
                                   uint16_t aSize)
 {
     NS_ASSERTION(mMathTable, "Math data has not yet been loaded. TryGetMathData() first.");
     return mMathTable->GetMathVariantsSize(aGlyphID, aVertical, aSize);
 }
 bool
 gfxFontEntry::GetMathVariantsParts(uint32_t aGlyphID, bool aVertical,
                                    uint32_t aGlyphs[4])
 {
     NS_ASSERTION(mMathTable, "Math data has not yet been loaded. TryGetMathData() first.");
     return mMathTable->GetMathVariantsParts(aGlyphID, aVertical, aGlyphs);
 }
 /**
  * FontTableBlobData
  *
  * See FontTableHashEntry for the general strategy.
  */
 class gfxFontEntry::FontTableBlobData {
 public:
     // Adopts the content of aBuffer.
     FontTableBlobData(FallibleTArray<uint8_t>& aBuffer)
         : mHashtable(nullptr), mHashKey(0)
     {
         MOZ_COUNT_CTOR(FontTableBlobData);
         mTableData.SwapElements(aBuffer);
     }
     ~FontTableBlobData() {
         MOZ_COUNT_DTOR(FontTableBlobData);
         if (mHashtable && mHashKey) {
             mHashtable->RemoveEntry(mHashKey);
         }
     }
     // Useful for creating blobs
     const char *GetTable() const
     {
         return reinterpret_cast<const char*>(mTableData.Elements());
     }
     uint32_t GetTableLength() const { return mTableData.Length(); }
     // Tell this FontTableBlobData to remove the HashEntry when this is
     // destroyed.
     void ManageHashEntry(nsTHashtable<FontTableHashEntry> *aHashtable,
                          uint32_t aHashKey)
     {
         mHashtable = aHashtable;
         mHashKey = aHashKey;
     }
     // Disconnect from the HashEntry (because the blob has already been
     // removed from the hashtable).
     void ForgetHashEntry()
     {
         mHashtable = nullptr;
         mHashKey = 0;
     }
     size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const {
         return mTableData.SizeOfExcludingThis(aMallocSizeOf);
     }
     size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const {
         return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
     }
 private:
     // The font table data block, owned (via adoption)
     FallibleTArray<uint8_t> mTableData;
     // The blob destroy function needs to know the owning hashtable
     // and the hashtable key, so that it can remove the entry.
     nsTHashtable<FontTableHashEntry> *mHashtable;
     uint32_t                          mHashKey;
     // not implemented
     FontTableBlobData(const FontTableBlobData&);
 };
 hb_blob_t *
 gfxFontEntry::FontTableHashEntry::
 ShareTableAndGetBlob(FallibleTArray<uint8_t>& aTable,
                      nsTHashtable<FontTableHashEntry> *aHashtable)
 {
     Clear();
     // adopts elements of aTable
     mSharedBlobData = new FontTableBlobData(aTable);
     mBlob = hb_blob_create(mSharedBlobData->GetTable(),
                            mSharedBlobData->GetTableLength(),
                            HB_MEMORY_MODE_READONLY,
                            mSharedBlobData, DeleteFontTableBlobData);
     if (!mSharedBlobData) {
         // The FontTableBlobData was destroyed during hb_blob_create().
         // The (empty) blob is still be held in the hashtable with a strong
         // reference.
         return hb_blob_reference(mBlob);
     }
     // Tell the FontTableBlobData to remove this hash entry when destroyed.
     // The hashtable does not keep a strong reference.
     mSharedBlobData->ManageHashEntry(aHashtable, GetKey());
     return mBlob;
 }
 void
 gfxFontEntry::FontTableHashEntry::Clear()
 {
     // If the FontTableBlobData is managing the hash entry, then the blob is
     // not owned by this HashEntry; otherwise there is strong reference to the
     // blob that must be removed.
     if (mSharedBlobData) {
         mSharedBlobData->ForgetHashEntry();
         mSharedBlobData = nullptr;
     } else if (mBlob) {
         hb_blob_destroy(mBlob);
     }
     mBlob = nullptr;
 }
 // a hb_destroy_func for hb_blob_create
 /* static */ void
 gfxFontEntry::FontTableHashEntry::DeleteFontTableBlobData(void *aBlobData)
 {
     delete static_cast<FontTableBlobData*>(aBlobData);
 }
 hb_blob_t *
 gfxFontEntry::FontTableHashEntry::GetBlob() const
 {
     return hb_blob_reference(mBlob);
 }
 bool
 gfxFontEntry::GetExistingFontTable(uint32_t aTag, hb_blob_t **aBlob)
 {
     if (!mFontTableCache) {
         // we do this here rather than on fontEntry construction
         // because not all shapers will access the table cache at all
         mFontTableCache = new nsTHashtable<FontTableHashEntry>(10);
     }
     FontTableHashEntry *entry = mFontTableCache->GetEntry(aTag);
     if (!entry) {
         return false;
     }
     *aBlob = entry->GetBlob();
     return true;
 }
 hb_blob_t *
 gfxFontEntry::ShareFontTableAndGetBlob(uint32_t aTag,
                                        FallibleTArray<uint8_t>* aBuffer)
 {
     if (MOZ_UNLIKELY(!mFontTableCache)) {
         // we do this here rather than on fontEntry construction
         // because not all shapers will access the table cache at all
       mFontTableCache = new nsTHashtable<FontTableHashEntry>(10);
     }
     FontTableHashEntry *entry = mFontTableCache->PutEntry(aTag);
     if (MOZ_UNLIKELY(!entry)) { // OOM
         return nullptr;
     }
     if (!aBuffer) {
         // ensure the entry is null
         entry->Clear();
         return nullptr;
     }
     return entry->ShareTableAndGetBlob(*aBuffer, mFontTableCache);
 }
 static int
 DirEntryCmp(const void* aKey, const void* aItem)
 {
     int32_t tag = *static_cast<const int32_t*>(aKey);
     const TableDirEntry* entry = static_cast<const TableDirEntry*>(aItem);
     return tag - int32_t(entry->tag);
 }
 hb_blob_t*
 gfxFontEntry::GetTableFromFontData(const void* aFontData, uint32_t aTableTag)
 {
     const SFNTHeader* header =
         reinterpret_cast<const SFNTHeader*>(aFontData);
     const TableDirEntry* dir =
         reinterpret_cast<const TableDirEntry*>(header + 1);
     dir = static_cast<const TableDirEntry*>
         (bsearch(&aTableTag, dir, uint16_t(header->numTables),
                  sizeof(TableDirEntry), DirEntryCmp));
     if (dir) {
         return hb_blob_create(reinterpret_cast<const char*>(aFontData) +
                                   dir->offset, dir->length,
                               HB_MEMORY_MODE_READONLY, nullptr, nullptr);
     }
     return nullptr;
 }
 already_AddRefed<gfxCharacterMap>
 gfxFontEntry::GetCMAPFromFontInfo(FontInfoData *aFontInfoData,
                                   uint32_t& aUVSOffset,
                                   bool& aSymbolFont)
 {
     if (!aFontInfoData || !aFontInfoData->mLoadCmaps) {
         return nullptr;
     }
     return aFontInfoData->GetCMAP(mName, aUVSOffset, aSymbolFont);
 }
 hb_blob_t *
 gfxFontEntry::GetFontTable(uint32_t aTag)
 {
     hb_blob_t *blob;
     if (GetExistingFontTable(aTag, &blob)) {
         return blob;
     }
     FallibleTArray<uint8_t> buffer;
     bool haveTable = NS_SUCCEEDED(CopyFontTable(aTag, buffer));
     return ShareFontTableAndGetBlob(aTag, haveTable ? &buffer : nullptr);
 }
 // callback for HarfBuzz to get a font table (in hb_blob_t form)
 // from the font entry (passed as aUserData)
 /*static*/ hb_blob_t *
 gfxFontEntry::HBGetTable(hb_face_t *face, uint32_t aTag, void *aUserData)
 {
     gfxFontEntry *fontEntry = static_cast<gfxFontEntry*>(aUserData);
     // bug 589682 - ignore the GDEF table in buggy fonts (applies to
     // Italic and BoldItalic faces of Times New Roman)
     if (aTag == TRUETYPE_TAG('G','D','E','F') &&
         fontEntry->IgnoreGDEF()) {
         return nullptr;
     }
     // bug 721719 - ignore the GSUB table in buggy fonts (applies to Roboto,
     // at least on some Android ICS devices; set in gfxFT2FontList.cpp)
     if (aTag == TRUETYPE_TAG('G','S','U','B') &&
         fontEntry->IgnoreGSUB()) {
         return nullptr;
     }
     return fontEntry->GetFontTable(aTag);
 }
 /*static*/ void
 gfxFontEntry::HBFaceDeletedCallback(void *aUserData)
 {
     gfxFontEntry *fe = static_cast<gfxFontEntry*>(aUserData);
     fe->ForgetHBFace();
 }
 void
 gfxFontEntry::ForgetHBFace()
 {
     mHBFace = nullptr;
 }
 hb_face_t*
 gfxFontEntry::GetHBFace()
 {
     if (!mHBFace) {
         mHBFace = hb_face_create_for_tables(HBGetTable, this,
                                             HBFaceDeletedCallback);
         return mHBFace;
     }
     return hb_face_reference(mHBFace);
 }
 /*static*/ const void*
 gfxFontEntry::GrGetTable(const void *aAppFaceHandle, unsigned int aName,
                          size_t *aLen)
 {
     gfxFontEntry *fontEntry =
         static_cast<gfxFontEntry*>(const_cast<void*>(aAppFaceHandle));
     hb_blob_t *blob = fontEntry->GetFontTable(aName);
     if (blob) {
         unsigned int blobLength;
         const void *tableData = hb_blob_get_data(blob, &blobLength);
         fontEntry->mGrTableMap->Put(tableData, blob);
         *aLen = blobLength;
         return tableData;
     }
     *aLen = 0;
     return nullptr;
 }
 /*static*/ void
 gfxFontEntry::GrReleaseTable(const void *aAppFaceHandle,
                              const void *aTableBuffer)
 {
     gfxFontEntry *fontEntry =
         static_cast<gfxFontEntry*>(const_cast<void*>(aAppFaceHandle));
     void *data;
     if (fontEntry->mGrTableMap->Get(aTableBuffer, &data)) {
         fontEntry->mGrTableMap->Remove(aTableBuffer);
         hb_blob_destroy(static_cast<hb_blob_t*>(data));
     }
 }
 gr_face*
 gfxFontEntry::GetGrFace()
 {
     if (!mGrFaceInitialized) {
         gr_face_ops faceOps = {
             sizeof(gr_face_ops),
             GrGetTable,
             GrReleaseTable
         };
         mGrTableMap = new nsDataHashtable<nsPtrHashKey<const void>,void*>;
         mGrFace = gr_make_face_with_ops(this, &faceOps, gr_face_default);
         mGrFaceInitialized = true;
     }
     ++mGrFaceRefCnt;
     return mGrFace;
 }
 void
 gfxFontEntry::ReleaseGrFace(gr_face *aFace)
 {
     MOZ_ASSERT(aFace == mGrFace); // sanity-check
     MOZ_ASSERT(mGrFaceRefCnt > 0);
     if (--mGrFaceRefCnt == 0) {
         gr_face_destroy(mGrFace);
         mGrFace = nullptr;
         mGrFaceInitialized = false;
         delete mGrTableMap;
         mGrTableMap = nullptr;
     }
 }
 void
 gfxFontEntry::DisconnectSVG()
 {
     if (mSVGInitialized && mSVGGlyphs) {
         mSVGGlyphs = nullptr;
         mSVGInitialized = false;
     }
 }
 bool
 gfxFontEntry::HasFontTable(uint32_t aTableTag)
 {
     AutoTable table(this, aTableTag);
     return table && hb_blob_get_length(table) > 0;
 }
 void
 gfxFontEntry::CheckForGraphiteTables()
 {
     mHasGraphiteTables = HasFontTable(TRUETYPE_TAG('S','i','l','f'));
 }
 /* static */ size_t
 gfxFontEntry::FontTableHashEntry::SizeOfEntryExcludingThis
     (FontTableHashEntry *aEntry,
      MallocSizeOf aMallocSizeOf,
      void* aUserArg)
 {
     size_t n = 0;
     if (aEntry->mBlob) {
         n += aMallocSizeOf(aEntry->mBlob);
     }
     if (aEntry->mSharedBlobData) {
         n += aEntry->mSharedBlobData->SizeOfIncludingThis(aMallocSizeOf);
     }
     return n;
 }
 void
 gfxFontEntry::AddSizeOfExcludingThis(MallocSizeOf aMallocSizeOf,
                                      FontListSizes* aSizes) const
 {
     aSizes->mFontListSize += mName.SizeOfExcludingThisIfUnshared(aMallocSizeOf);
     // cmaps are shared so only non-shared cmaps are included here
     if (mCharacterMap && mCharacterMap->mBuildOnTheFly) {
         aSizes->mCharMapsSize +=
             mCharacterMap->SizeOfIncludingThis(aMallocSizeOf);
     }
     if (mFontTableCache) {
         aSizes->mFontTableCacheSize +=
             mFontTableCache->SizeOfExcludingThis(
                 FontTableHashEntry::SizeOfEntryExcludingThis,
                 aMallocSizeOf);
     }
 }
 void
 gfxFontEntry::AddSizeOfIncludingThis(MallocSizeOf aMallocSizeOf,
                                      FontListSizes* aSizes) const
 {
     aSizes->mFontListSize += aMallocSizeOf(this);
     AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
 }
 //////////////////////////////////////////////////////////////////////////////
 //
 // class gfxFontFamily
 //
 //////////////////////////////////////////////////////////////////////////////
 // we consider faces with mStandardFace == true to be "greater than" those with false,
 // because during style matching, later entries will replace earlier ones
 class FontEntryStandardFaceComparator {
   public:
     bool Equals(const nsRefPtr<gfxFontEntry>& a, const nsRefPtr<gfxFontEntry>& b) const {
         return a->mStandardFace == b->mStandardFace;
     }
     bool LessThan(const nsRefPtr<gfxFontEntry>& a, const nsRefPtr<gfxFontEntry>& b) const {
         return (a->mStandardFace == false && b->mStandardFace == true);
     }
 };
 void
 gfxFontFamily::SortAvailableFonts()
 {
     mAvailableFonts.Sort(FontEntryStandardFaceComparator());
 }
 bool
 gfxFontFamily::HasOtherFamilyNames()
 {
     // need to read in other family names to determine this
     if (!mOtherFamilyNamesInitialized) {
         ReadOtherFamilyNames(gfxPlatformFontList::PlatformFontList());  // sets mHasOtherFamilyNames
     }
     return mHasOtherFamilyNames;
 }
 gfxFontEntry*
 gfxFontFamily::FindFontForStyle(const gfxFontStyle& aFontStyle,
                                 bool& aNeedsSyntheticBold)
 {
     if (!mHasStyles)
         FindStyleVariations(); // collect faces for the family, if not already done
     NS_ASSERTION(mAvailableFonts.Length() > 0, "font family with no faces!");
     aNeedsSyntheticBold = false;
     int8_t baseWeight = aFontStyle.ComputeWeight();
     bool wantBold = baseWeight >= 6;
     // If the family has only one face, we simply return it; no further checking needed
     if (mAvailableFonts.Length() == 1) {
         gfxFontEntry *fe = mAvailableFonts[0];
         aNeedsSyntheticBold = wantBold && !fe->IsBold();
         return fe;
     }
     bool wantItalic = (aFontStyle.style &
                        (NS_FONT_STYLE_ITALIC | NS_FONT_STYLE_OBLIQUE)) != 0;
     // Most families are "simple", having just Regular/Bold/Italic/BoldItalic,
     // or some subset of these. In this case, we have exactly 4 entries in mAvailableFonts,
     // stored in the above order; note that some of the entries may be nullptr.
     // We can then pick the required entry based on whether the request is for
     // bold or non-bold, italic or non-italic, without running the more complex
     // matching algorithm used for larger families with many weights and/or widths.
     if (mIsSimpleFamily) {
         // Family has no more than the "standard" 4 faces, at fixed indexes;
         // calculate which one we want.
         // Note that we cannot simply return it as not all 4 faces are necessarily present.
         uint8_t faceIndex = (wantItalic ? kItalicMask : 0) |
                             (wantBold ? kBoldMask : 0);
         // if the desired style is available, return it directly
         gfxFontEntry *fe = mAvailableFonts[faceIndex];
         if (fe) {
             // no need to set aNeedsSyntheticBold here as we matched the boldness request
             return fe;
         }
         // order to check fallback faces in a simple family, depending on requested style
         static const uint8_t simpleFallbacks[4][3] = {
             { kBoldFaceIndex, kItalicFaceIndex, kBoldItalicFaceIndex },   // fallbacks for Regular
             { kRegularFaceIndex, kBoldItalicFaceIndex, kItalicFaceIndex },// Bold
             { kBoldItalicFaceIndex, kRegularFaceIndex, kBoldFaceIndex },  // Italic
             { kItalicFaceIndex, kBoldFaceIndex, kRegularFaceIndex }       // BoldItalic
         };
         const uint8_t *order = simpleFallbacks[faceIndex];
         for (uint8_t trial = 0; trial < 3; ++trial) {
             // check remaining faces in order of preference to find the first that actually exists
             fe = mAvailableFonts[order[trial]];
             if (fe) {
                 aNeedsSyntheticBold = wantBold && !fe->IsBold();
                 return fe;
             }
         }
         // this can't happen unless we have totally broken the font-list manager!
         NS_NOTREACHED("no face found in simple font family!");
         return nullptr;
     }
     // This is a large/rich font family, so we do full style- and weight-matching:
     // first collect a list of weights that are the best match for the requested
     // font-stretch and font-style, then pick the best weight match among those
     // available.
     gfxFontEntry *weightList[10] = { 0 };
     bool foundWeights = FindWeightsForStyle(weightList, wantItalic, aFontStyle.stretch);
     if (!foundWeights) {
         return nullptr;
     }
     // First find a match for the best weight
     int8_t matchBaseWeight = 0;
     int8_t i = baseWeight;
     // Need to special case when normal face doesn't exist but medium does.
     // In that case, use medium otherwise weights < 400
     if (baseWeight == 4 && !weightList[4]) {
         i = 5; // medium
     }
     // Loop through weights, since one exists loop will terminate
     int8_t direction = (baseWeight > 5) ? 1 : -1;
     for (; ; i += direction) {
         if (weightList[i]) {
             matchBaseWeight = i;
             break;
         }
         // If we've reached one side without finding a font,
         // start over and go the other direction until we find a match
         if (i == 1 || i == 9) {
             i = baseWeight;
             direction = -direction;
         }
     }
     NS_ASSERTION(matchBaseWeight != 0,
                  "weight mapping should always find at least one font in a family");
     gfxFontEntry *matchFE = weightList[matchBaseWeight];
     NS_ASSERTION(matchFE,
                  "weight mapping should always find at least one font in a family");
     if (!matchFE->IsBold() && baseWeight >= 6)
     {
         aNeedsSyntheticBold = true;
     }
     return matchFE;
 }
 void
 gfxFontFamily::CheckForSimpleFamily()
 {
     // already checked this family
     if (mIsSimpleFamily) {
         return;
     };
     uint32_t count = mAvailableFonts.Length();
     if (count > 4 || count == 0) {
         return; // can't be "simple" if there are >4 faces;
                 // if none then the family is unusable anyway
     }
     if (count == 1) {
         mIsSimpleFamily = true;
         return;
     }
     int16_t firstStretch = mAvailableFonts[0]->Stretch();
     gfxFontEntry *faces[4] = { 0 };
     for (uint8_t i = 0; i < count; ++i) {
         gfxFontEntry *fe = mAvailableFonts[i];
         if (fe->Stretch() != firstStretch) {
             return; // font-stretch doesn't match, don't treat as simple family
         }
         uint8_t faceIndex = (fe->IsItalic() ? kItalicMask : 0) |
                             (fe->Weight() >= 600 ? kBoldMask : 0);
         if (faces[faceIndex]) {
             return; // two faces resolve to the same slot; family isn't "simple"
         }
         faces[faceIndex] = fe;
     }
     // we have successfully slotted the available faces into the standard
     // 4-face framework
     mAvailableFonts.SetLength(4);
     for (uint8_t i = 0; i < 4; ++i) {
         if (mAvailableFonts[i].get() != faces[i]) {
             mAvailableFonts[i].swap(faces[i]);
         }
     }
     mIsSimpleFamily = true;
 }
 static inline uint32_t
 StyleDistance(gfxFontEntry *aFontEntry,
               bool anItalic, int16_t aStretch)
 {
     // Compute a measure of the "distance" between the requested style
     // and the given fontEntry,
     // considering italicness and font-stretch but not weight.
     int32_t distance = 0;
     if (aStretch != aFontEntry->mStretch) {
         // stretch values are in the range -4 .. +4
         // if aStretch is positive, we prefer more-positive values;
         // if zero or negative, prefer more-negative
         if (aStretch > 0) {
             distance = (aFontEntry->mStretch - aStretch) * 2;
         } else {
             distance = (aStretch - aFontEntry->mStretch) * 2;
         }
         // if the computed "distance" here is negative, it means that
         // aFontEntry lies in the "non-preferred" direction from aStretch,
         // so we treat that as larger than any preferred-direction distance
         // (max possible is 8) by adding an extra 10 to the absolute value
         if (distance < 0) {
             distance = -distance + 10;
         }
     }
     if (aFontEntry->IsItalic() != anItalic) {
         distance += 1;
     }
     return uint32_t(distance);
 }
 bool
 gfxFontFamily::FindWeightsForStyle(gfxFontEntry* aFontsForWeights[],
                                    bool anItalic, int16_t aStretch)
 {
     uint32_t foundWeights = 0;
     uint32_t bestMatchDistance = 0xffffffff;
     uint32_t count = mAvailableFonts.Length();
     for (uint32_t i = 0; i < count; i++) {
         // this is not called for "simple" families, and therefore it does not
         // need to check the mAvailableFonts entries for nullptr.
         gfxFontEntry *fe = mAvailableFonts[i];
         uint32_t distance = StyleDistance(fe, anItalic, aStretch);
         if (distance <= bestMatchDistance) {
             int8_t wt = fe->mWeight / 100;
             NS_ASSERTION(wt >= 1 && wt < 10, "invalid weight in fontEntry");
             if (!aFontsForWeights[wt]) {
                 // record this as a possible candidate for weight matching
                 aFontsForWeights[wt] = fe;
                 ++foundWeights;
             } else {
                 uint32_t prevDistance =
                     StyleDistance(aFontsForWeights[wt], anItalic, aStretch);
                 if (prevDistance >= distance) {
                     // replacing a weight we already found,
                     // so don't increment foundWeights
                     aFontsForWeights[wt] = fe;
                 }
             }
             bestMatchDistance = distance;
         }
     }
     NS_ASSERTION(foundWeights > 0, "Font family containing no faces?");
     if (foundWeights == 1) {
         // no need to cull entries if we only found one weight
         return true;
     }
     // we might have recorded some faces that were a partial style match, but later found
     // others that were closer; in this case, we need to cull the poorer matches from the
     // weight list we'll return
     for (uint32_t i = 0; i < 10; ++i) {
         if (aFontsForWeights[i] &&
             StyleDistance(aFontsForWeights[i], anItalic, aStretch) > bestMatchDistance)
         {
             aFontsForWeights[i] = 0;
         }
     }
     return (foundWeights > 0);
 }
 void gfxFontFamily::LocalizedName(nsAString& aLocalizedName)
 {
     // just return the primary name; subclasses should override
     aLocalizedName = mName;
 }
 // metric for how close a given font matches a style
 static int32_t
 CalcStyleMatch(gfxFontEntry *aFontEntry, const gfxFontStyle *aStyle)
 {
     int32_t rank = 0;
     if (aStyle) {
          // italics
          bool wantItalic =
              (aStyle->style & (NS_FONT_STYLE_ITALIC | NS_FONT_STYLE_OBLIQUE)) != 0;
          if (aFontEntry->IsItalic() == wantItalic) {
              rank += 10;
          }
         // measure of closeness of weight to the desired value
         rank += 9 - DeprecatedAbs(aFontEntry->Weight() / 100 - aStyle->ComputeWeight());
     } else {
         // if no font to match, prefer non-bold, non-italic fonts
         if (!aFontEntry->IsItalic()) {
             rank += 3;
         }
         if (!aFontEntry->IsBold()) {
             rank += 2;
         }
     }
     return rank;
 }
 #define RANK_MATCHED_CMAP   20
 void
 gfxFontFamily::FindFontForChar(GlobalFontMatch *aMatchData)
 {
     if (mFamilyCharacterMapInitialized && !TestCharacterMap(aMatchData->mCh)) {
         // none of the faces in the family support the required char,
         // so bail out immediately
         return;
     }
     bool needsBold;
     gfxFontStyle normal;
     gfxFontEntry *fe = FindFontForStyle(
                   (aMatchData->mStyle == nullptr) ? *aMatchData->mStyle : normal,
                   needsBold);
     if (fe && !fe->SkipDuringSystemFallback()) {
         int32_t rank = 0;
         if (fe->TestCharacterMap(aMatchData->mCh)) {
             rank += RANK_MATCHED_CMAP;
             aMatchData->mCount++;
 #ifdef PR_LOGGING
             PRLogModuleInfo *log = gfxPlatform::GetLog(eGfxLog_textrun);
             if (MOZ_UNLIKELY(PR_LOG_TEST(log, PR_LOG_DEBUG))) {
                 uint32_t unicodeRange = FindCharUnicodeRange(aMatchData->mCh);
                 uint32_t script = GetScriptCode(aMatchData->mCh);
                 PR_LOG(log, PR_LOG_DEBUG,\
                        ("(textrun-systemfallback-fonts) char: u+%6.6x "
                         "unicode-range: %d script: %d match: [%s]\n",
                         aMatchData->mCh,
                         unicodeRange, script,
                         NS_ConvertUTF16toUTF8(fe->Name()).get()));
             }
 #endif
         }
         aMatchData->mCmapsTested++;
         if (rank == 0) {
             return;
         }
          // omitting from original windows code -- family name, lang group, pitch
          // not available in current FontEntry implementation
         rank += CalcStyleMatch(fe, aMatchData->mStyle);
         // xxx - add whether AAT font with morphing info for specific lang groups
         if (rank > aMatchData->mMatchRank
             || (rank == aMatchData->mMatchRank &&
                 Compare(fe->Name(), aMatchData->mBestMatch->Name()) > 0))
         {
             aMatchData->mBestMatch = fe;
             aMatchData->mMatchedFamily = this;
             aMatchData->mMatchRank = rank;
         }
     }
 }
 void
 gfxFontFamily::SearchAllFontsForChar(GlobalFontMatch *aMatchData)
 {
     uint32_t i, numFonts = mAvailableFonts.Length();
     for (i = 0; i < numFonts; i++) {
         gfxFontEntry *fe = mAvailableFonts[i];
         if (fe && fe->TestCharacterMap(aMatchData->mCh)) {
             int32_t rank = RANK_MATCHED_CMAP;
             rank += CalcStyleMatch(fe, aMatchData->mStyle);
             if (rank > aMatchData->mMatchRank
                 || (rank == aMatchData->mMatchRank &&
                     Compare(fe->Name(), aMatchData->mBestMatch->Name()) > 0))
             {
                 aMatchData->mBestMatch = fe;
                 aMatchData->mMatchedFamily = this;
                 aMatchData->mMatchRank = rank;
             }
         }
     }
 }
 /*static*/ void
 gfxFontFamily::ReadOtherFamilyNamesForFace(const nsAString& aFamilyName,
                                            const char *aNameData,
                                            uint32_t aDataLength,
                                            nsTArray<nsString>& aOtherFamilyNames,
                                            bool useFullName)
 {
     const gfxFontUtils::NameHeader *nameHeader =
         reinterpret_cast<const gfxFontUtils::NameHeader*>(aNameData);
     uint32_t nameCount = nameHeader->count;
     if (nameCount * sizeof(gfxFontUtils::NameRecord) > aDataLength) {
         NS_WARNING("invalid font (name records)");
         return;
     }
     const gfxFontUtils::NameRecord *nameRecord =
         reinterpret_cast<const gfxFontUtils::NameRecord*>(aNameData + sizeof(gfxFontUtils::NameHeader));
     uint32_t stringsBase = uint32_t(nameHeader->stringOffset);
     for (uint32_t i = 0; i < nameCount; i++, nameRecord++) {
         uint32_t nameLen = nameRecord->length;
         uint32_t nameOff = nameRecord->offset;  // offset from base of string storage
         if (stringsBase + nameOff + nameLen > aDataLength) {
             NS_WARNING("invalid font (name table strings)");
             return;
         }
         uint16_t nameID = nameRecord->nameID;
         if ((useFullName && nameID == gfxFontUtils::NAME_ID_FULL) ||
             (!useFullName && (nameID == gfxFontUtils::NAME_ID_FAMILY ||
                               nameID == gfxFontUtils::NAME_ID_PREFERRED_FAMILY))) {
             nsAutoString otherFamilyName;
             bool ok = gfxFontUtils::DecodeFontName(aNameData + stringsBase + nameOff,
                                                      nameLen,
                                                      uint32_t(nameRecord->platformID),
                                                      uint32_t(nameRecord->encodingID),
                                                      uint32_t(nameRecord->languageID),
                                                      otherFamilyName);
             // add if not same as canonical family name
             if (ok && otherFamilyName != aFamilyName) {
                 aOtherFamilyNames.AppendElement(otherFamilyName);
             }
         }
     }
 }
 // returns true if other names were found, false otherwise
 bool
 gfxFontFamily::ReadOtherFamilyNamesForFace(gfxPlatformFontList *aPlatformFontList,
                                            hb_blob_t           *aNameTable,
                                            bool                 useFullName)
 {
     uint32_t dataLength;
     const char *nameData = hb_blob_get_data(aNameTable, &dataLength);
     nsAutoTArray<nsString,4> otherFamilyNames;
     ReadOtherFamilyNamesForFace(mName, nameData, dataLength,
                                 otherFamilyNames, useFullName);
     uint32_t n = otherFamilyNames.Length();
     for (uint32_t i = 0; i < n; i++) {
         aPlatformFontList->AddOtherFamilyName(this, otherFamilyNames[i]);
     }
     return n != 0;
 }
 void
 gfxFontFamily::ReadOtherFamilyNames(gfxPlatformFontList *aPlatformFontList)
 {
     if (mOtherFamilyNamesInitialized)
         return;
     mOtherFamilyNamesInitialized = true;
     FindStyleVariations();
     // read in other family names for the first face in the list
     uint32_t i, numFonts = mAvailableFonts.Length();
     const uint32_t kNAME = TRUETYPE_TAG('n','a','m','e');
     for (i = 0; i < numFonts; ++i) {
         gfxFontEntry *fe = mAvailableFonts[i];
         if (!fe) {
             continue;
         }
         gfxFontEntry::AutoTable nameTable(fe, kNAME);
         if (!nameTable) {
             continue;
         }
         mHasOtherFamilyNames = ReadOtherFamilyNamesForFace(aPlatformFontList,
                                                            nameTable);
         break;
     }
     // read in other names for the first face in the list with the assumption
     // that if extra names don't exist in that face then they don't exist in
     // other faces for the same font
     if (!mHasOtherFamilyNames)
         return;
     // read in names for all faces, needed to catch cases where fonts have
     // family names for individual weights (e.g. Hiragino Kaku Gothic Pro W6)
     for ( ; i < numFonts; i++) {
         gfxFontEntry *fe = mAvailableFonts[i];
         if (!fe) {
             continue;
         }
         gfxFontEntry::AutoTable nameTable(fe, kNAME);
         if (!nameTable) {
             continue;
         }
         ReadOtherFamilyNamesForFace(aPlatformFontList, nameTable);
     }
 }
 void
 gfxFontFamily::ReadFaceNames(gfxPlatformFontList *aPlatformFontList,
                              bool aNeedFullnamePostscriptNames,
                              FontInfoData *aFontInfoData)
 {
     // if all needed names have already been read, skip
     if (mOtherFamilyNamesInitialized &&
         (mFaceNamesInitialized || !aNeedFullnamePostscriptNames))
         return;
     bool asyncFontLoaderDisabled = false;
 #if defined(XP_MACOSX)
     // bug 975460 - async font loader crashes sometimes under 10.6, disable
     if (!nsCocoaFeatures::OnLionOrLater()) {
         asyncFontLoaderDisabled = true;
     }
 #endif
     if (!mOtherFamilyNamesInitialized &&
         aFontInfoData &&
         aFontInfoData->mLoadOtherNames &&
         !asyncFontLoaderDisabled)
     {
         nsAutoTArray<nsString,4> otherFamilyNames;
         bool foundOtherNames =
             aFontInfoData->GetOtherFamilyNames(mName, otherFamilyNames);
         if (foundOtherNames) {
             uint32_t i, n = otherFamilyNames.Length();
             for (i = 0; i < n; i++) {
                 aPlatformFontList->AddOtherFamilyName(this, otherFamilyNames[i]);
             }
         }
         mOtherFamilyNamesInitialized = true;
     }
     // if all needed data has been initialized, return
     if (mOtherFamilyNamesInitialized &&
         (mFaceNamesInitialized || !aNeedFullnamePostscriptNames)) {
         return;
     }
     FindStyleVariations(aFontInfoData);
     // check again, as style enumeration code may have loaded names
     if (mOtherFamilyNamesInitialized &&
         (mFaceNamesInitialized || !aNeedFullnamePostscriptNames)) {
         return;
     }
     uint32_t i, numFonts = mAvailableFonts.Length();
     const uint32_t kNAME = TRUETYPE_TAG('n','a','m','e');
     bool firstTime = true, readAllFaces = false;
     for (i = 0; i < numFonts; ++i) {
         gfxFontEntry *fe = mAvailableFonts[i];
         if (!fe) {
             continue;
         }
         nsAutoString fullname, psname;
         bool foundFaceNames = false;
         if (!mFaceNamesInitialized &&
             aNeedFullnamePostscriptNames &&
             aFontInfoData &&
             aFontInfoData->mLoadFaceNames) {
             aFontInfoData->GetFaceNames(fe->Name(), fullname, psname);
             if (!fullname.IsEmpty()) {
                 aPlatformFontList->AddFullname(fe, fullname);
             }
             if (!psname.IsEmpty()) {
                 aPlatformFontList->AddPostscriptName(fe, psname);
             }
             foundFaceNames = true;
             // found everything needed? skip to next font
             if (mOtherFamilyNamesInitialized) {
                 continue;
             }
         }
         // load directly from the name table
         gfxFontEntry::AutoTable nameTable(fe, kNAME);
         if (!nameTable) {
             continue;
         }
         if (aNeedFullnamePostscriptNames && !foundFaceNames) {
             if (gfxFontUtils::ReadCanonicalName(
                     nameTable, gfxFontUtils::NAME_ID_FULL, fullname) == NS_OK)
             {
                 aPlatformFontList->AddFullname(fe, fullname);
             }
             if (gfxFontUtils::ReadCanonicalName(
                     nameTable, gfxFontUtils::NAME_ID_POSTSCRIPT, psname) == NS_OK)
             {
                 aPlatformFontList->AddPostscriptName(fe, psname);
             }
         }
         if (!mOtherFamilyNamesInitialized && (firstTime || readAllFaces)) {
             bool foundOtherName = ReadOtherFamilyNamesForFace(aPlatformFontList,
                                                               nameTable);
             // if the first face has a different name, scan all faces, otherwise
             // assume the family doesn't have other names
             if (firstTime && foundOtherName) {
                 mHasOtherFamilyNames = true;
                 readAllFaces = true;
             }
             firstTime = false;
         }
         // if not reading in any more names, skip other faces
         if (!readAllFaces && !aNeedFullnamePostscriptNames) {
             break;
         }
     }
     mFaceNamesInitialized = true;
     mOtherFamilyNamesInitialized = true;
 }
 gfxFontEntry*
 gfxFontFamily::FindFont(const nsAString& aPostscriptName)
 {
     // find the font using a simple linear search
     uint32_t numFonts = mAvailableFonts.Length();
     for (uint32_t i = 0; i < numFonts; i++) {
         gfxFontEntry *fe = mAvailableFonts[i].get();
         if (fe && fe->Name() == aPostscriptName)
             return fe;
     }
     return nullptr;
 }
 void
 gfxFontFamily::ReadAllCMAPs(FontInfoData *aFontInfoData)
 {
     FindStyleVariations(aFontInfoData);
     uint32_t i, numFonts = mAvailableFonts.Length();
     for (i = 0; i < numFonts; i++) {
         gfxFontEntry *fe = mAvailableFonts[i];
         // don't try to load cmaps for downloadable fonts not yet loaded
         if (!fe || fe->mIsProxy) {
             continue;
         }
         fe->ReadCMAP(aFontInfoData);
         mFamilyCharacterMap.Union(*(fe->mCharacterMap));
     }
     mFamilyCharacterMap.Compact();
     mFamilyCharacterMapInitialized = true;
 }
 void
 gfxFontFamily::AddSizeOfExcludingThis(MallocSizeOf aMallocSizeOf,
                                       FontListSizes* aSizes) const
 {
     aSizes->mFontListSize +=
         mName.SizeOfExcludingThisIfUnshared(aMallocSizeOf);
     aSizes->mCharMapsSize +=
         mFamilyCharacterMap.SizeOfExcludingThis(aMallocSizeOf);
     aSizes->mFontListSize +=
         mAvailableFonts.SizeOfExcludingThis(aMallocSizeOf);
     for (uint32_t i = 0; i < mAvailableFonts.Length(); ++i) {
         gfxFontEntry *fe = mAvailableFonts[i];
         if (fe) {
             fe->AddSizeOfIncludingThis(aMallocSizeOf, aSizes);
         }
     }
 }
 void
 gfxFontFamily::AddSizeOfIncludingThis(MallocSizeOf aMallocSizeOf,
                                       FontListSizes* aSizes) const
 {
     aSizes->mFontListSize += aMallocSizeOf(this);
     AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
 }
 /*
  * gfxFontCache - global cache of gfxFont instances.
  * Expires unused fonts after a short interval;
  * notifies fonts to age their cached shaped-word records;
  * observes memory-pressure notification and tells fonts to clear their
  * shaped-word caches to free up memory.
  */
 MOZ_DEFINE_MALLOC_SIZE_OF(FontCacheMallocSizeOf)
 NS_IMPL_ISUPPORTS(gfxFontCache::MemoryReporter, nsIMemoryReporter)
 NS_IMETHODIMP
 gfxFontCache::MemoryReporter::CollectReports
     (nsIMemoryReporterCallback* aCb,
      nsISupports* aClosure)
 {
     FontCacheSizes sizes;
     gfxFontCache::GetCache()->AddSizeOfIncludingThis(&FontCacheMallocSizeOf,
                                                      &sizes);
     aCb->Callback(EmptyCString(),
                   NS_LITERAL_CSTRING("explicit/gfx/font-cache"),
                   KIND_HEAP, UNITS_BYTES, sizes.mFontInstances,
                   NS_LITERAL_CSTRING("Memory used for active font instances."),
                   aClosure);
     aCb->Callback(EmptyCString(),
                   NS_LITERAL_CSTRING("explicit/gfx/font-shaped-words"),
                   KIND_HEAP, UNITS_BYTES, sizes.mShapedWords,
                   NS_LITERAL_CSTRING("Memory used to cache shaped glyph data."),
                   aClosure);
     return NS_OK;
 }
 NS_IMPL_ISUPPORTS(gfxFontCache::Observer, nsIObserver)
 NS_IMETHODIMP
 gfxFontCache::Observer::Observe(nsISupports *aSubject,
                                 const char *aTopic,
                                 const char16_t *someData)
 {
     if (!nsCRT::strcmp(aTopic, "memory-pressure")) {
         gfxFontCache *fontCache = gfxFontCache::GetCache();
         if (fontCache) {
             fontCache->FlushShapedWordCaches();
         }
     } else {
         NS_NOTREACHED("unexpected notification topic");
     }
     return NS_OK;
 }
 nsresult
 gfxFontCache::Init()
 {
     NS_ASSERTION(!gGlobalCache, "Where did this come from?");
     gGlobalCache = new gfxFontCache();
     if (!gGlobalCache) {
         return NS_ERROR_OUT_OF_MEMORY;
     }
     RegisterStrongMemoryReporter(new MemoryReporter());
     return NS_OK;
 }
 void
 gfxFontCache::Shutdown()
 {
     delete gGlobalCache;
     gGlobalCache = nullptr;
 #ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
     printf("Textrun storage high water mark=%d\n", gTextRunStorageHighWaterMark);
     printf("Total number of fonts=%d\n", gFontCount);
     printf("Total glyph extents allocated=%d (size %d)\n", gGlyphExtentsCount,
             int(gGlyphExtentsCount*sizeof(gfxGlyphExtents)));
     printf("Total glyph extents width-storage size allocated=%d\n", gGlyphExtentsWidthsTotalSize);
     printf("Number of simple glyph extents eagerly requested=%d\n", gGlyphExtentsSetupEagerSimple);
     printf("Number of tight glyph extents eagerly requested=%d\n", gGlyphExtentsSetupEagerTight);
     printf("Number of tight glyph extents lazily requested=%d\n", gGlyphExtentsSetupLazyTight);
     printf("Number of simple glyph extent setups that fell back to tight=%d\n", gGlyphExtentsSetupFallBackToTight);
 #endif
 }
 gfxFontCache::gfxFontCache()
     : nsExpirationTracker<gfxFont,3>(FONT_TIMEOUT_SECONDS * 1000)
 {
     nsCOMPtr<nsIObserverService> obs = GetObserverService();
     if (obs) {
         obs->AddObserver(new Observer, "memory-pressure", false);
     }
 #ifndef RELEASE_BUILD
     // Currently disabled for release builds, due to unexplained crashes
     // during expiration; see bug 717175 & 894798.
     mWordCacheExpirationTimer = do_CreateInstance("@mozilla.org/timer;1");
     if (mWordCacheExpirationTimer) {
         mWordCacheExpirationTimer->
             InitWithFuncCallback(WordCacheExpirationTimerCallback, this,
                                  SHAPED_WORD_TIMEOUT_SECONDS * 1000,
                                  nsITimer::TYPE_REPEATING_SLACK);
     }
 #endif
 }
 gfxFontCache::~gfxFontCache()
 {
     // Ensure the user font cache releases its references to font entries,
     // so they aren't kept alive after the font instances and font-list
     // have been shut down.
     gfxUserFontSet::UserFontCache::Shutdown();
     if (mWordCacheExpirationTimer) {
         mWordCacheExpirationTimer->Cancel();
         mWordCacheExpirationTimer = nullptr;
     }
     // Expire everything that has a zero refcount, so we don't leak them.
     AgeAllGenerations();
     // All fonts should be gone.
     NS_WARN_IF_FALSE(mFonts.Count() == 0,
                      "Fonts still alive while shutting down gfxFontCache");
     // Note that we have to delete everything through the expiration
     // tracker, since there might be fonts not in the hashtable but in
     // the tracker.
 }
 bool
 gfxFontCache::HashEntry::KeyEquals(const KeyTypePointer aKey) const
 {
     return aKey->mFontEntry == mFont->GetFontEntry() &&
            aKey->mStyle->Equals(*mFont->GetStyle());
 }
 already_AddRefed<gfxFont>
 gfxFontCache::Lookup(const gfxFontEntry *aFontEntry,
                      const gfxFontStyle *aStyle)
 {
     Key key(aFontEntry, aStyle);
     HashEntry *entry = mFonts.GetEntry(key);
     Telemetry::Accumulate(Telemetry::FONT_CACHE_HIT, entry != nullptr);
     if (!entry)
         return nullptr;
     nsRefPtr<gfxFont> font = entry->mFont;
     return font.forget();
 }
 void
 gfxFontCache::AddNew(gfxFont *aFont)
 {
     Key key(aFont->GetFontEntry(), aFont->GetStyle());
     HashEntry *entry = mFonts.PutEntry(key);
     if (!entry)
         return;
     gfxFont *oldFont = entry->mFont;
     entry->mFont = aFont;
     // Assert that we can find the entry we just put in (this fails if the key
     // has a NaN float value in it, e.g. 'sizeAdjust').
     MOZ_ASSERT(entry == mFonts.GetEntry(key));
     // If someone's asked us to replace an existing font entry, then that's a
     // bit weird, but let it happen, and expire the old font if it's not used.
     if (oldFont && oldFont->GetExpirationState()->IsTracked()) {
         // if oldFont == aFont, recount should be > 0,
         // so we shouldn't be here.
         NS_ASSERTION(aFont != oldFont, "new font is tracked for expiry!");
         NotifyExpired(oldFont);
     }
 }
 void
 gfxFontCache::NotifyReleased(gfxFont *aFont)
 {
     nsresult rv = AddObject(aFont);
     if (NS_FAILED(rv)) {
         // We couldn't track it for some reason. Kill it now.
         DestroyFont(aFont);
     }
     // Note that we might have fonts that aren't in the hashtable, perhaps because
     // of OOM adding to the hashtable or because someone did an AddNew where
     // we already had a font. These fonts are added to the expiration tracker
     // anyway, even though Lookup can't resurrect them. Eventually they will
     // expire and be deleted.
 }
 void
 gfxFontCache::NotifyExpired(gfxFont *aFont)
 {
     aFont->ClearCachedWords();
     RemoveObject(aFont);
     DestroyFont(aFont);
 }
 void
 gfxFontCache::DestroyFont(gfxFont *aFont)
 {
     Key key(aFont->GetFontEntry(), aFont->GetStyle());
     HashEntry *entry = mFonts.GetEntry(key);
     if (entry && entry->mFont == aFont) {
         mFonts.RemoveEntry(key);
     }
     NS_ASSERTION(aFont->GetRefCount() == 0,
                  "Destroying with non-zero ref count!");
     delete aFont;
 }
 /*static*/
 PLDHashOperator
 gfxFontCache::AgeCachedWordsForFont(HashEntry* aHashEntry, void* aUserData)
 {
     aHashEntry->mFont->AgeCachedWords();
     return PL_DHASH_NEXT;
 }
 /*static*/
 void
 gfxFontCache::WordCacheExpirationTimerCallback(nsITimer* aTimer, void* aCache)
 {
     gfxFontCache* cache = static_cast<gfxFontCache*>(aCache);
     cache->mFonts.EnumerateEntries(AgeCachedWordsForFont, nullptr);
 }
 /*static*/
 PLDHashOperator
 gfxFontCache::ClearCachedWordsForFont(HashEntry* aHashEntry, void* aUserData)
 {
     aHashEntry->mFont->ClearCachedWords();
     return PL_DHASH_NEXT;
 }
 /*static*/
 size_t
 gfxFontCache::AddSizeOfFontEntryExcludingThis(HashEntry* aHashEntry,
                                               MallocSizeOf aMallocSizeOf,
                                               void* aUserArg)
 {
     HashEntry *entry = static_cast<HashEntry*>(aHashEntry);
     FontCacheSizes *sizes = static_cast<FontCacheSizes*>(aUserArg);
     entry->mFont->AddSizeOfExcludingThis(aMallocSizeOf, sizes);
     // The entry's size is recorded in the |sizes| parameter, so we return zero
     // here to the hashtable enumerator.
     return 0;
 }
 void
 gfxFontCache::AddSizeOfExcludingThis(MallocSizeOf aMallocSizeOf,
                                      FontCacheSizes* aSizes) const
 {
     // TODO: add the overhead of the expiration tracker (generation arrays)
     aSizes->mFontInstances +=
         mFonts.SizeOfExcludingThis(AddSizeOfFontEntryExcludingThis,
                                    aMallocSizeOf, aSizes);
 }
 void
 gfxFontCache::AddSizeOfIncludingThis(MallocSizeOf aMallocSizeOf,
                                      FontCacheSizes* aSizes) const
 {
     aSizes->mFontInstances += aMallocSizeOf(this);
     AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
 }
 #define MAX_SSXX_VALUE 99
 #define MAX_CVXX_VALUE 99
 static void
 LookupAlternateValues(gfxFontFeatureValueSet *featureLookup,
                       const nsAString& aFamily,
                       const nsTArray<gfxAlternateValue>& altValue,
                       nsTArray<gfxFontFeature>& aFontFeatures)
 {
     uint32_t numAlternates = altValue.Length();
     for (uint32_t i = 0; i < numAlternates; i++) {
         const gfxAlternateValue& av = altValue.ElementAt(i);
         nsAutoTArray<uint32_t,4> values;
         // map <family, name, feature> ==> <values>
         bool found =
             featureLookup->GetFontFeatureValuesFor(aFamily, av.alternate,
                                                    av.value, values);
         uint32_t numValues = values.Length();
         // nothing defined, skip
         if (!found || numValues == 0) {
             continue;
         }
         gfxFontFeature feature;
         if (av.alternate == NS_FONT_VARIANT_ALTERNATES_CHARACTER_VARIANT) {
             NS_ASSERTION(numValues <= 2,
                          "too many values allowed for character-variant");
             // character-variant(12 3) ==> 'cv12' = 3
             uint32_t nn = values.ElementAt(0);
             // ignore values greater than 99
             if (nn == 0 || nn > MAX_CVXX_VALUE) {
                 continue;
             }
             feature.mValue = 1;
             if (numValues > 1) {
                 feature.mValue = values.ElementAt(1);
             }
             feature.mTag = HB_TAG('c','v',('0' + nn / 10), ('0' + nn % 10));
             aFontFeatures.AppendElement(feature);
         } else if (av.alternate == NS_FONT_VARIANT_ALTERNATES_STYLESET) {
             // styleset(1 2 7) ==> 'ss01' = 1, 'ss02' = 1, 'ss07' = 1
             feature.mValue = 1;
             for (uint32_t v = 0; v < numValues; v++) {
                 uint32_t nn = values.ElementAt(v);
                 if (nn == 0 || nn > MAX_SSXX_VALUE) {
                     continue;
                 }
                 feature.mTag = HB_TAG('s','s',('0' + nn / 10), ('0' + nn % 10));
                 aFontFeatures.AppendElement(feature);
             }
         } else {
             NS_ASSERTION(numValues == 1,
                    "too many values for font-specific font-variant-alternates");
             feature.mValue = values.ElementAt(0);
             switch (av.alternate) {
                 case NS_FONT_VARIANT_ALTERNATES_STYLISTIC:  // salt
                     feature.mTag = HB_TAG('s','a','l','t');
                     break;
                 case NS_FONT_VARIANT_ALTERNATES_SWASH:  // swsh, cswh
                     feature.mTag = HB_TAG('s','w','s','h');
                     aFontFeatures.AppendElement(feature);
                     feature.mTag = HB_TAG('c','s','w','h');
                     break;
                 case NS_FONT_VARIANT_ALTERNATES_ORNAMENTS: // ornm
                     feature.mTag = HB_TAG('o','r','n','m');
                     break;
                 case NS_FONT_VARIANT_ALTERNATES_ANNOTATION: // nalt
                     feature.mTag = HB_TAG('n','a','l','t');
                     break;
                 default:
                     feature.mTag = 0;
                     break;
             }
             NS_ASSERTION(feature.mTag, "unsupported alternate type");
             if (!feature.mTag) {
                 continue;
             }
             aFontFeatures.AppendElement(feature);
         }
     }
 }
 /* static */ bool
 gfxFontShaper::MergeFontFeatures(
     const gfxFontStyle *aStyle,
     const nsTArray<gfxFontFeature>& aFontFeatures,
     bool aDisableLigatures,
     const nsAString& aFamilyName,
     nsDataHashtable<nsUint32HashKey,uint32_t>& aMergedFeatures)
 {
     uint32_t numAlts = aStyle->alternateValues.Length();
     const nsTArray<gfxFontFeature>& styleRuleFeatures =
         aStyle->featureSettings;
     // bail immediately if nothing to do
     if (styleRuleFeatures.IsEmpty() &&
         aFontFeatures.IsEmpty() &&
         !aDisableLigatures &&
         numAlts == 0) {
         return false;
     }
     // Ligature features are enabled by default in the generic shaper,
     // so we explicitly turn them off if necessary (for letter-spacing)
     if (aDisableLigatures) {
         aMergedFeatures.Put(HB_TAG('l','i','g','a'), 0);
         aMergedFeatures.Put(HB_TAG('c','l','i','g'), 0);
     }
     // add feature values from font
     uint32_t i, count;
     count = aFontFeatures.Length();
     for (i = 0; i < count; i++) {
         const gfxFontFeature& feature = aFontFeatures.ElementAt(i);
         aMergedFeatures.Put(feature.mTag, feature.mValue);
     }
     // add font-specific feature values from style rules
     if (aStyle->featureValueLookup && numAlts > 0) {
         nsAutoTArray<gfxFontFeature,4> featureList;
         // insert list of alternate feature settings
         LookupAlternateValues(aStyle->featureValueLookup, aFamilyName,
                               aStyle->alternateValues, featureList);
         count = featureList.Length();
         for (i = 0; i < count; i++) {
             const gfxFontFeature& feature = featureList.ElementAt(i);
             aMergedFeatures.Put(feature.mTag, feature.mValue);
         }
     }
     // add feature values from style rules
     count = styleRuleFeatures.Length();
     for (i = 0; i < count; i++) {
         const gfxFontFeature& feature = styleRuleFeatures.ElementAt(i);
         aMergedFeatures.Put(feature.mTag, feature.mValue);
     }
     return aMergedFeatures.Count() != 0;
 }
 void
 gfxFont::RunMetrics::CombineWith(const RunMetrics& aOther, bool aOtherIsOnLeft)
 {
     mAscent = std::max(mAscent, aOther.mAscent);
     mDescent = std::max(mDescent, aOther.mDescent);
     if (aOtherIsOnLeft) {
         mBoundingBox =
             (mBoundingBox + gfxPoint(aOther.mAdvanceWidth, 0)).Union(aOther.mBoundingBox);
     } else {
         mBoundingBox =
             mBoundingBox.Union(aOther.mBoundingBox + gfxPoint(mAdvanceWidth, 0));
     }
     mAdvanceWidth += aOther.mAdvanceWidth;
 }
 gfxFont::gfxFont(gfxFontEntry *aFontEntry, const gfxFontStyle *aFontStyle,
                  AntialiasOption anAAOption, cairo_scaled_font_t *aScaledFont) :
     mScaledFont(aScaledFont),
     mFontEntry(aFontEntry), mIsValid(true),
     mApplySyntheticBold(false),
     mStyle(*aFontStyle),
     mAdjustedSize(0.0),
     mFUnitsConvFactor(0.0f),
     mAntialiasOption(anAAOption)
 {
 #ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
     ++gFontCount;
 #endif
     mKerningSet = HasFeatureSet(HB_TAG('k','e','r','n'), mKerningEnabled);
 }
 static PLDHashOperator
 NotifyFontDestroyed(nsPtrHashKey<gfxFont::GlyphChangeObserver>* aKey,
                     void* aClosure)
 {
     aKey->GetKey()->ForgetFont();
     return PL_DHASH_NEXT;
 }
 gfxFont::~gfxFont()
 {
     uint32_t i, count = mGlyphExtentsArray.Length();
     // We destroy the contents of mGlyphExtentsArray explicitly instead of
     // using nsAutoPtr because VC++ can't deal with nsTArrays of nsAutoPtrs
     // of classes that lack a proper copy constructor
     for (i = 0; i < count; ++i) {
         delete mGlyphExtentsArray[i];
     }
     mFontEntry->NotifyFontDestroyed(this);
     if (mGlyphChangeObservers) {
         mGlyphChangeObservers->EnumerateEntries(NotifyFontDestroyed, nullptr);
     }
 }
 gfxFloat
 gfxFont::GetGlyphHAdvance(gfxContext *aCtx, uint16_t aGID)
 {
     if (!SetupCairoFont(aCtx)) {
         return 0;
     }
     if (ProvidesGlyphWidths()) {
         return GetGlyphWidth(aCtx, aGID) / 65536.0;
     }
     if (mFUnitsConvFactor == 0.0f) {
         GetMetrics();
     }
     NS_ASSERTION(mFUnitsConvFactor > 0.0f,
                  "missing font unit conversion factor");
     if (!mHarfBuzzShaper) {
         mHarfBuzzShaper = new gfxHarfBuzzShaper(this);
     }
     gfxHarfBuzzShaper* shaper =
         static_cast<gfxHarfBuzzShaper*>(mHarfBuzzShaper.get());
     if (!shaper->Initialize()) {
         return 0;
     }
     return shaper->GetGlyphHAdvance(aCtx, aGID) / 65536.0;
 }
 /*static*/
 PLDHashOperator
 gfxFont::AgeCacheEntry(CacheHashEntry *aEntry, void *aUserData)
 {
     if (!aEntry->mShapedWord) {
         NS_ASSERTION(aEntry->mShapedWord, "cache entry has no gfxShapedWord!");
         return PL_DHASH_REMOVE;
     }
     if (aEntry->mShapedWord->IncrementAge() == kShapedWordCacheMaxAge) {
         return PL_DHASH_REMOVE;
     }
     return PL_DHASH_NEXT;
 }
 static void
 CollectLookupsByFeature(hb_face_t *aFace, hb_tag_t aTableTag,
                         uint32_t aFeatureIndex, hb_set_t *aLookups)
 {
     uint32_t lookups[32];
     uint32_t i, len, offset;
     offset = 0;
     do {
         len = ArrayLength(lookups);
         hb_ot_layout_feature_get_lookups(aFace, aTableTag, aFeatureIndex,
                                          offset, &len, lookups);
         for (i = 0; i < len; i++) {
             hb_set_add(aLookups, lookups[i]);
         }
         offset += len;
     } while (len == ArrayLength(lookups));
 }
 static void
 CollectLookupsByLanguage(hb_face_t *aFace, hb_tag_t aTableTag,
                          const nsTHashtable<nsUint32HashKey>&
                              aSpecificFeatures,
                          hb_set_t *aOtherLookups,
                          hb_set_t *aSpecificFeatureLookups,
                          uint32_t aScriptIndex, uint32_t aLangIndex)
 {
     uint32_t reqFeatureIndex;
     if (hb_ot_layout_language_get_required_feature_index(aFace, aTableTag,
                                                          aScriptIndex,
                                                          aLangIndex,
                                                          &reqFeatureIndex)) {
         CollectLookupsByFeature(aFace, aTableTag, reqFeatureIndex,
                                 aOtherLookups);
     }
     uint32_t featureIndexes[32];
     uint32_t i, len, offset;
     offset = 0;
     do {
         len = ArrayLength(featureIndexes);
         hb_ot_layout_language_get_feature_indexes(aFace, aTableTag,
                                                   aScriptIndex, aLangIndex,
                                                   offset, &len, featureIndexes);
         for (i = 0; i < len; i++) {
             uint32_t featureIndex = featureIndexes[i];
             // get the feature tag
             hb_tag_t featureTag;
             uint32_t tagLen = 1;
             hb_ot_layout_language_get_feature_tags(aFace, aTableTag,
                                                    aScriptIndex, aLangIndex,
                                                    offset + i, &tagLen,
                                                    &featureTag);
             // collect lookups
             hb_set_t *lookups = aSpecificFeatures.GetEntry(featureTag) ?
                                     aSpecificFeatureLookups : aOtherLookups;
             CollectLookupsByFeature(aFace, aTableTag, featureIndex, lookups);
         }
         offset += len;
     } while (len == ArrayLength(featureIndexes));
 }
 static bool
 HasLookupRuleWithGlyphByScript(hb_face_t *aFace, hb_tag_t aTableTag,
                                hb_tag_t aScriptTag, uint32_t aScriptIndex,
                                uint16_t aGlyph,
                                const nsTHashtable<nsUint32HashKey>&
                                    aDefaultFeatures,
                                bool& aHasDefaultFeatureWithGlyph)
 {
     uint32_t numLangs, lang;
     hb_set_t *defaultFeatureLookups = hb_set_create();
     hb_set_t *nonDefaultFeatureLookups = hb_set_create();
     // default lang
     CollectLookupsByLanguage(aFace, aTableTag, aDefaultFeatures,
                              nonDefaultFeatureLookups, defaultFeatureLookups,
                              aScriptIndex,
                              HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX);
     // iterate over langs
     numLangs = hb_ot_layout_script_get_language_tags(aFace, aTableTag,
                                                      aScriptIndex, 0,
                                                      nullptr, nullptr);
     for (lang = 0; lang < numLangs; lang++) {
         CollectLookupsByLanguage(aFace, aTableTag, aDefaultFeatures,
                                  nonDefaultFeatureLookups,
                                  defaultFeatureLookups,
                                  aScriptIndex, lang);
     }
     // look for the glyph among default feature lookups
     aHasDefaultFeatureWithGlyph = false;
     hb_set_t *glyphs = hb_set_create();
     hb_codepoint_t index = -1;
     while (hb_set_next(defaultFeatureLookups, &index)) {
         hb_ot_layout_lookup_collect_glyphs(aFace, aTableTag, index,
                                            glyphs, glyphs, glyphs,
                                            glyphs);
         if (hb_set_has(glyphs, aGlyph)) {
             aHasDefaultFeatureWithGlyph = true;
             break;
         }
     }
     // look for the glyph among non-default feature lookups
     // if no default feature lookups contained spaces
     bool hasNonDefaultFeatureWithGlyph = false;
     if (!aHasDefaultFeatureWithGlyph) {
         hb_set_clear(glyphs);
         index = -1;
         while (hb_set_next(nonDefaultFeatureLookups, &index)) {
             hb_ot_layout_lookup_collect_glyphs(aFace, aTableTag, index,
                                                glyphs, glyphs, glyphs,
                                                glyphs);
             if (hb_set_has(glyphs, aGlyph)) {
                 hasNonDefaultFeatureWithGlyph = true;
                 break;
             }
         }
     }
     hb_set_destroy(glyphs);
     hb_set_destroy(defaultFeatureLookups);
     hb_set_destroy(nonDefaultFeatureLookups);
     return aHasDefaultFeatureWithGlyph || hasNonDefaultFeatureWithGlyph;
 }
 static void
 HasLookupRuleWithGlyph(hb_face_t *aFace, hb_tag_t aTableTag, bool& aHasGlyph,
                        hb_tag_t aSpecificFeature, bool& aHasGlyphSpecific,
                        uint16_t aGlyph)
 {
     // iterate over the scripts in the font
     uint32_t numScripts, numLangs, script, lang;
     hb_set_t *otherLookups = hb_set_create();
     hb_set_t *specificFeatureLookups = hb_set_create();
     nsTHashtable<nsUint32HashKey> specificFeature;
     specificFeature.PutEntry(aSpecificFeature);
     numScripts = hb_ot_layout_table_get_script_tags(aFace, aTableTag, 0,
                                                     nullptr, nullptr);
     for (script = 0; script < numScripts; script++) {
         // default lang
         CollectLookupsByLanguage(aFace, aTableTag, specificFeature,
                                  otherLookups, specificFeatureLookups,
                                  script, HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX);
         // iterate over langs
         numLangs = hb_ot_layout_script_get_language_tags(aFace, HB_OT_TAG_GPOS,
                                                          script, 0,
                                                          nullptr, nullptr);
         for (lang = 0; lang < numLangs; lang++) {
             CollectLookupsByLanguage(aFace, aTableTag, specificFeature,
                                      otherLookups, specificFeatureLookups,
                                      script, lang);
         }
     }
     // look for the glyph among non-specific feature lookups
     hb_set_t *glyphs = hb_set_create();
     hb_codepoint_t index = -1;
     while (hb_set_next(otherLookups, &index)) {
         hb_ot_layout_lookup_collect_glyphs(aFace, aTableTag, index,
                                            glyphs, glyphs, glyphs,
                                            glyphs);
         if (hb_set_has(glyphs, aGlyph)) {
             aHasGlyph = true;
             break;
         }
     }
     // look for the glyph among specific feature lookups
     hb_set_clear(glyphs);
     index = -1;
     while (hb_set_next(specificFeatureLookups, &index)) {
         hb_ot_layout_lookup_collect_glyphs(aFace, aTableTag, index,
                                            glyphs, glyphs, glyphs,
                                            glyphs);
         if (hb_set_has(glyphs, aGlyph)) {
             aHasGlyphSpecific = true;
             break;
         }
     }
     hb_set_destroy(glyphs);
     hb_set_destroy(specificFeatureLookups);
     hb_set_destroy(otherLookups);
 }
 nsDataHashtable<nsUint32HashKey, int32_t> *gfxFont::sScriptTagToCode = nullptr;
 nsTHashtable<nsUint32HashKey>             *gfxFont::sDefaultFeatures = nullptr;
 static inline bool
 HasSubstitution(uint32_t *aBitVector, uint32_t aBit) {
     return (aBitVector[aBit >> 5] & (1 << (aBit & 0x1f))) != 0;
 }
 // union of all default substitution features across scripts
 static const hb_tag_t defaultFeatures[] = {
     HB_TAG('a','b','v','f'),
     HB_TAG('a','b','v','s'),
     HB_TAG('a','k','h','n'),
     HB_TAG('b','l','w','f'),
     HB_TAG('b','l','w','s'),
     HB_TAG('c','a','l','t'),
     HB_TAG('c','c','m','p'),
     HB_TAG('c','f','a','r'),
     HB_TAG('c','j','c','t'),
     HB_TAG('c','l','i','g'),
     HB_TAG('f','i','n','2'),
     HB_TAG('f','i','n','3'),
     HB_TAG('f','i','n','a'),
     HB_TAG('h','a','l','f'),
     HB_TAG('h','a','l','n'),
     HB_TAG('i','n','i','t'),
     HB_TAG('i','s','o','l'),
     HB_TAG('l','i','g','a'),
     HB_TAG('l','j','m','o'),
     HB_TAG('l','o','c','l'),
     HB_TAG('l','t','r','a'),
     HB_TAG('l','t','r','m'),
     HB_TAG('m','e','d','2'),
     HB_TAG('m','e','d','i'),
     HB_TAG('m','s','e','t'),
     HB_TAG('n','u','k','t'),
     HB_TAG('p','r','e','f'),
     HB_TAG('p','r','e','s'),
     HB_TAG('p','s','t','f'),
     HB_TAG('p','s','t','s'),
     HB_TAG('r','c','l','t'),
     HB_TAG('r','l','i','g'),
     HB_TAG('r','k','r','f'),
     HB_TAG('r','p','h','f'),
     HB_TAG('r','t','l','a'),
     HB_TAG('r','t','l','m'),
     HB_TAG('t','j','m','o'),
     HB_TAG('v','a','t','u'),
     HB_TAG('v','e','r','t'),
     HB_TAG('v','j','m','o')
 };
 void
 gfxFont::CheckForFeaturesInvolvingSpace()
 {
     mFontEntry->mHasSpaceFeaturesInitialized = true;
 #ifdef PR_LOGGING
     bool log = LOG_FONTINIT_ENABLED();
     TimeStamp start;
     if (MOZ_UNLIKELY(log)) {
         start = TimeStamp::Now();
     }
 #endif
     bool result = false;
     uint32_t spaceGlyph = GetSpaceGlyph();
     if (!spaceGlyph) {
         return;
     }
     hb_face_t *face = GetFontEntry()->GetHBFace();
     // GSUB lookups - examine per script
     if (hb_ot_layout_has_substitution(face)) {
         // set up the script ==> code hashtable if needed
         if (!sScriptTagToCode) {
             sScriptTagToCode =
                 new nsDataHashtable<nsUint32HashKey,
                                     int32_t>(MOZ_NUM_SCRIPT_CODES);
             sScriptTagToCode->Put(HB_TAG('D','F','L','T'), MOZ_SCRIPT_COMMON);
             for (int32_t s = MOZ_SCRIPT_ARABIC; s < MOZ_NUM_SCRIPT_CODES; s++) {
                 hb_script_t scriptTag = hb_script_t(GetScriptTagForCode(s));
                 hb_tag_t s1, s2;
                 hb_ot_tags_from_script(scriptTag, &s1, &s2);
                 sScriptTagToCode->Put(s1, s);
                 if (s2 != HB_OT_TAG_DEFAULT_SCRIPT) {
                     sScriptTagToCode->Put(s2, s);
                 }
             }
             uint32_t numDefaultFeatures = ArrayLength(defaultFeatures);
             sDefaultFeatures =
                 new nsTHashtable<nsUint32HashKey>(numDefaultFeatures);
             for (uint32_t i = 0; i < numDefaultFeatures; i++) {
                 sDefaultFeatures->PutEntry(defaultFeatures[i]);
             }
         }
         // iterate over the scripts in the font
         hb_tag_t scriptTags[8];
         uint32_t len, offset = 0;
         do {
             len = ArrayLength(scriptTags);
             hb_ot_layout_table_get_script_tags(face, HB_OT_TAG_GSUB, offset,
                                                &len, scriptTags);
             for (uint32_t i = 0; i < len; i++) {
                 bool isDefaultFeature = false;
                 int32_t s;
                 if (!HasLookupRuleWithGlyphByScript(face, HB_OT_TAG_GSUB,
                                                     scriptTags[i], offset + i,
                                                     spaceGlyph,
                                                     *sDefaultFeatures,
                                                     isDefaultFeature) ||
                     !sScriptTagToCode->Get(scriptTags[i], &s))
                 {
                     continue;
                 }
                 result = true;
                 uint32_t index = s >> 5;
                 uint32_t bit = s & 0x1f;
                 if (isDefaultFeature) {
                     mFontEntry->mDefaultSubSpaceFeatures[index] |= (1 << bit);
                 } else {
                     mFontEntry->mNonDefaultSubSpaceFeatures[index] |= (1 << bit);
                 }
             }
             offset += len;
         } while (len == ArrayLength(scriptTags));
     }
     // spaces in default features of default script?
     // ==> can't use word cache, skip GPOS analysis
     bool canUseWordCache = true;
     if (HasSubstitution(mFontEntry->mDefaultSubSpaceFeatures,
                         MOZ_SCRIPT_COMMON)) {
         canUseWordCache = false;
     }
     // GPOS lookups - distinguish kerning from non-kerning features
     mFontEntry->mHasSpaceFeaturesKerning = false;
     mFontEntry->mHasSpaceFeaturesNonKerning = false;
     if (canUseWordCache && hb_ot_layout_has_positioning(face)) {
         bool hasKerning = false, hasNonKerning = false;
         HasLookupRuleWithGlyph(face, HB_OT_TAG_GPOS, hasNonKerning,
                                HB_TAG('k','e','r','n'), hasKerning, spaceGlyph);
         if (hasKerning || hasNonKerning) {
             result = true;
         }
         mFontEntry->mHasSpaceFeaturesKerning = hasKerning;
         mFontEntry->mHasSpaceFeaturesNonKerning = hasNonKerning;
     }
     hb_face_destroy(face);
     mFontEntry->mHasSpaceFeatures = result;
 #ifdef PR_LOGGING
     if (MOZ_UNLIKELY(log)) {
         TimeDuration elapsed = TimeStamp::Now() - start;
         LOG_FONTINIT((
             "(fontinit-spacelookups) font: %s - "
             "subst default: %8.8x %8.8x %8.8x %8.8x "
             "subst non-default: %8.8x %8.8x %8.8x %8.8x "
             "kerning: %s non-kerning: %s time: %6.3f\n",
             NS_ConvertUTF16toUTF8(mFontEntry->Name()).get(),
             mFontEntry->mDefaultSubSpaceFeatures[3],
             mFontEntry->mDefaultSubSpaceFeatures[2],
             mFontEntry->mDefaultSubSpaceFeatures[1],
             mFontEntry->mDefaultSubSpaceFeatures[0],
             mFontEntry->mNonDefaultSubSpaceFeatures[3],
             mFontEntry->mNonDefaultSubSpaceFeatures[2],
             mFontEntry->mNonDefaultSubSpaceFeatures[1],
             mFontEntry->mNonDefaultSubSpaceFeatures[0],
             (mFontEntry->mHasSpaceFeaturesKerning ? "true" : "false"),
             (mFontEntry->mHasSpaceFeaturesNonKerning ? "true" : "false"),
             elapsed.ToMilliseconds()
         ));
     }
 #endif
 }
 bool
 gfxFont::HasSubstitutionRulesWithSpaceLookups(int32_t aRunScript)
 {
     NS_ASSERTION(GetFontEntry()->mHasSpaceFeaturesInitialized,
                  "need to initialize space lookup flags");
     NS_ASSERTION(aRunScript < MOZ_NUM_SCRIPT_CODES, "weird script code");
     if (aRunScript == MOZ_SCRIPT_INVALID ||
         aRunScript >= MOZ_NUM_SCRIPT_CODES) {
         return false;
     }
     // default features have space lookups ==> true
     if (HasSubstitution(mFontEntry->mDefaultSubSpaceFeatures,
                         MOZ_SCRIPT_COMMON) ||
         HasSubstitution(mFontEntry->mDefaultSubSpaceFeatures,
                         aRunScript))
     {
         return true;
     }
     // non-default features have space lookups and some type of
     // font feature, in font or style is specified ==> true
     if ((HasSubstitution(mFontEntry->mNonDefaultSubSpaceFeatures,
                          MOZ_SCRIPT_COMMON) ||
          HasSubstitution(mFontEntry->mNonDefaultSubSpaceFeatures,
                          aRunScript)) &&
         (!mStyle.featureSettings.IsEmpty() ||
          !mFontEntry->mFeatureSettings.IsEmpty()))
     {
         return true;
     }
     return false;
 }
 bool
 gfxFont::SpaceMayParticipateInShaping(int32_t aRunScript)
 {
     // avoid checking fonts known not to include default space-dependent features
     if (MOZ_UNLIKELY(mFontEntry->mSkipDefaultFeatureSpaceCheck)) {
         if (!mKerningSet && mStyle.featureSettings.IsEmpty() &&
             mFontEntry->mFeatureSettings.IsEmpty()) {
             return false;
         }
     }
     // We record the presence of space-dependent features in the font entry
     // so that subsequent instantiations for the same font face won't
     // require us to re-check the tables; however, the actual check is done
     // by gfxFont because not all font entry subclasses know how to create
     // a harfbuzz face for introspection.
     if (!mFontEntry->mHasSpaceFeaturesInitialized) {
         CheckForFeaturesInvolvingSpace();
     }
     if (!mFontEntry->mHasSpaceFeatures) {
         return false;
     }
     // if font has substitution rules or non-kerning positioning rules
     // that involve spaces, bypass
     if (HasSubstitutionRulesWithSpaceLookups(aRunScript) ||
         mFontEntry->mHasSpaceFeaturesNonKerning) {
         return true;
     }
     // if kerning explicitly enabled/disabled via font-feature-settings or
     // font-kerning and kerning rules use spaces, only bypass when enabled
     if (mKerningSet && mFontEntry->mHasSpaceFeaturesKerning) {
         return mKerningEnabled;
     }
     return false;
 }
 bool
 gfxFont::HasFeatureSet(uint32_t aFeature, bool& aFeatureOn)
 {
     aFeatureOn = false;
     if (mStyle.featureSettings.IsEmpty() &&
         GetFontEntry()->mFeatureSettings.IsEmpty()) {
         return false;
     }
     // add feature values from font
     bool featureSet = false;
     uint32_t i, count;
     nsTArray<gfxFontFeature>& fontFeatures = GetFontEntry()->mFeatureSettings;
     count = fontFeatures.Length();
     for (i = 0; i < count; i++) {
         const gfxFontFeature& feature = fontFeatures.ElementAt(i);
         if (feature.mTag == aFeature) {
             featureSet = true;
             aFeatureOn = (feature.mValue != 0);
         }
     }
     // add feature values from style rules
     nsTArray<gfxFontFeature>& styleFeatures = mStyle.featureSettings;
     count = styleFeatures.Length();
     for (i = 0; i < count; i++) {
         const gfxFontFeature& feature = styleFeatures.ElementAt(i);
         if (feature.mTag == aFeature) {
             featureSet = true;
             aFeatureOn = (feature.mValue != 0);
         }
     }
     return featureSet;
 }
 /**
  * A helper function in case we need to do any rounding or other
  * processing here.
  */
 #define ToDeviceUnits(aAppUnits, aDevUnitsPerAppUnit) \
     (double(aAppUnits)*double(aDevUnitsPerAppUnit))
 struct GlyphBuffer {
 #define GLYPH_BUFFER_SIZE (2048/sizeof(cairo_glyph_t))
     cairo_glyph_t mGlyphBuffer[GLYPH_BUFFER_SIZE];
     unsigned int mNumGlyphs;
     GlyphBuffer()
         : mNumGlyphs(0) { }
     cairo_glyph_t *AppendGlyph() {
         return &mGlyphBuffer[mNumGlyphs++];
     }
     void Flush(cairo_t *aCR, DrawMode aDrawMode, bool aReverse,
                gfxTextContextPaint *aContextPaint,
                const gfxMatrix& aGlobalMatrix, bool aFinish = false) {
         // Ensure there's enough room for a glyph to be added to the buffer
         // and we actually have glyphs to draw
         if ((!aFinish && mNumGlyphs < GLYPH_BUFFER_SIZE) || !mNumGlyphs) {
             return;
         }
         if (aReverse) {
             for (uint32_t i = 0; i < mNumGlyphs/2; ++i) {
                 cairo_glyph_t tmp = mGlyphBuffer[i];
                 mGlyphBuffer[i] = mGlyphBuffer[mNumGlyphs - 1 - i];
                 mGlyphBuffer[mNumGlyphs - 1 - i] = tmp;
             }
         }
         if (aDrawMode == DrawMode::GLYPH_PATH) {
             cairo_glyph_path(aCR, mGlyphBuffer, mNumGlyphs);
         } else {
             if ((int(aDrawMode) & (int(DrawMode::GLYPH_STROKE) | int(DrawMode::GLYPH_STROKE_UNDERNEATH))) ==
                                   (int(DrawMode::GLYPH_STROKE) | int(DrawMode::GLYPH_STROKE_UNDERNEATH))) {
                 FlushStroke(aCR, aContextPaint, aGlobalMatrix);
             }
             if (int(aDrawMode) & int(DrawMode::GLYPH_FILL)) {
                 PROFILER_LABEL("GlyphBuffer", "cairo_show_glyphs");
                 nsRefPtr<gfxPattern> pattern;
                 if (aContextPaint &&
                     !!(pattern = aContextPaint->GetFillPattern(aGlobalMatrix))) {
                     cairo_save(aCR);
                     cairo_set_source(aCR, pattern->CairoPattern());
                 }
                 cairo_show_glyphs(aCR, mGlyphBuffer, mNumGlyphs);
                 if (pattern) {
                     cairo_restore(aCR);
                 }
             }
             if ((int(aDrawMode) & (int(DrawMode::GLYPH_STROKE) | int(DrawMode::GLYPH_STROKE_UNDERNEATH))) ==
                                   int(DrawMode::GLYPH_STROKE)) {
                 FlushStroke(aCR, aContextPaint, aGlobalMatrix);
             }
         }
         mNumGlyphs = 0;
     }
 private:
     void FlushStroke(cairo_t *aCR, gfxTextContextPaint *aContextPaint,
                      const gfxMatrix& aGlobalMatrix) {
         nsRefPtr<gfxPattern> pattern;
         if (aContextPaint &&
             !!(pattern = aContextPaint->GetStrokePattern(aGlobalMatrix))) {
             cairo_save(aCR);
             cairo_set_source(aCR, pattern->CairoPattern());
         }
         cairo_new_path(aCR);
         cairo_glyph_path(aCR, mGlyphBuffer, mNumGlyphs);
         cairo_stroke(aCR);
         if (pattern) {
             cairo_restore(aCR);
         }
     }
 #undef GLYPH_BUFFER_SIZE
 };
 static AntialiasMode Get2DAAMode(gfxFont::AntialiasOption aAAOption) {
   switch (aAAOption) {
   case gfxFont::kAntialiasSubpixel:
     return AntialiasMode::SUBPIXEL;
   case gfxFont::kAntialiasGrayscale:
     return AntialiasMode::GRAY;
   case gfxFont::kAntialiasNone:
     return AntialiasMode::NONE;
   default:
     return AntialiasMode::DEFAULT;
   }
 }
 struct GlyphBufferAzure {
 #define GLYPH_BUFFER_SIZE (2048/sizeof(Glyph))
     Glyph mGlyphBuffer[GLYPH_BUFFER_SIZE];
     unsigned int mNumGlyphs;
     GlyphBufferAzure()
         : mNumGlyphs(0) { }
     Glyph *AppendGlyph() {
         return &mGlyphBuffer[mNumGlyphs++];
     }
     void Flush(DrawTarget *aDT, gfxTextContextPaint *aContextPaint, ScaledFont *aFont,
                DrawMode aDrawMode, bool aReverse, const GlyphRenderingOptions *aOptions,
                gfxContext *aThebesContext, const Matrix *aInvFontMatrix, const DrawOptions &aDrawOptions,
                bool aFinish = false)
     {
         // Ensure there's enough room for a glyph to be added to the buffer
         if ((!aFinish && mNumGlyphs < GLYPH_BUFFER_SIZE) || !mNumGlyphs) {
             return;
         }
         if (aReverse) {
             Glyph *begin = &mGlyphBuffer[0];
             Glyph *end = &mGlyphBuffer[mNumGlyphs];
             std::reverse(begin, end);
         }
         gfx::GlyphBuffer buf;
         buf.mGlyphs = mGlyphBuffer;
         buf.mNumGlyphs = mNumGlyphs;
         gfxContext::AzureState state = aThebesContext->CurrentState();
         if ((int(aDrawMode) & (int(DrawMode::GLYPH_STROKE) | int(DrawMode::GLYPH_STROKE_UNDERNEATH))) ==
                               (int(DrawMode::GLYPH_STROKE) | int(DrawMode::GLYPH_STROKE_UNDERNEATH))) {
             FlushStroke(aDT, aContextPaint, aFont, aThebesContext, buf, state);
         }
         if (int(aDrawMode) & int(DrawMode::GLYPH_FILL)) {
             if (state.pattern || aContextPaint) {
                 Pattern *pat;
                 nsRefPtr<gfxPattern> fillPattern;
                 if (!aContextPaint ||
                     !(fillPattern = aContextPaint->GetFillPattern(aThebesContext->CurrentMatrix()))) {
                     if (state.pattern) {
                         pat = state.pattern->GetPattern(aDT, state.patternTransformChanged ? &state.patternTransform : nullptr);
                     } else {
                         pat = nullptr;
                     }
                 } else {
                     pat = fillPattern->GetPattern(aDT);
                 }
                 if (pat) {
                     Matrix saved;
                     Matrix *mat = nullptr;
                     if (aInvFontMatrix) {
                         // The brush matrix needs to be multiplied with the inverted matrix
                         // as well, to move the brush into the space of the glyphs. Before
                         // the render target transformation
                         // This relies on the returned Pattern not to be reused by
                         // others, but regenerated on GetPattern calls. This is true!
                         if (pat->GetType() == PatternType::LINEAR_GRADIENT) {
                             mat = &static_cast<LinearGradientPattern*>(pat)->mMatrix;
                         } else if (pat->GetType() == PatternType::RADIAL_GRADIENT) {
                             mat = &static_cast<RadialGradientPattern*>(pat)->mMatrix;
                         } else if (pat->GetType() == PatternType::SURFACE) {
                             mat = &static_cast<SurfacePattern*>(pat)->mMatrix;
                         }
                         if (mat) {
                             saved = *mat;
                             *mat = (*mat) * (*aInvFontMatrix);
                         }
                     }
                     aDT->FillGlyphs(aFont, buf, *pat,
                                     aDrawOptions, aOptions);
                     if (mat) {
                         *mat = saved;
                     }
                 }
             } else if (state.sourceSurface) {
                 aDT->FillGlyphs(aFont, buf, SurfacePattern(state.sourceSurface,
                                                            ExtendMode::CLAMP,
                                                            state.surfTransform),
                                 aDrawOptions, aOptions);
             } else {
                 aDT->FillGlyphs(aFont, buf, ColorPattern(state.color),
                                 aDrawOptions, aOptions);
             }
         }
         if (int(aDrawMode) & int(DrawMode::GLYPH_PATH)) {
             aThebesContext->EnsurePathBuilder();
 			Matrix mat = aDT->GetTransform();
             aFont->CopyGlyphsToBuilder(buf, aThebesContext->mPathBuilder, aDT->GetType(), &mat);
         }
         if ((int(aDrawMode) & (int(DrawMode::GLYPH_STROKE) | int(DrawMode::GLYPH_STROKE_UNDERNEATH))) ==
                               int(DrawMode::GLYPH_STROKE)) {
             FlushStroke(aDT, aContextPaint, aFont, aThebesContext, buf, state);
         }
         mNumGlyphs = 0;
     }
 private:
     void FlushStroke(DrawTarget *aDT, gfxTextContextPaint *aContextPaint,
                      ScaledFont *aFont, gfxContext *aThebesContext,
                      gfx::GlyphBuffer& aBuf, gfxContext::AzureState& aState)
     {
         RefPtr<Path> path = aFont->GetPathForGlyphs(aBuf, aDT);
         if (aContextPaint) {
             nsRefPtr<gfxPattern> strokePattern =
               aContextPaint->GetStrokePattern(aThebesContext->CurrentMatrix());
             if (strokePattern) {
                 aDT->Stroke(path, *strokePattern->GetPattern(aDT), aState.strokeOptions);
             }
         }
     }
 #undef GLYPH_BUFFER_SIZE
 };
 // Bug 674909. When synthetic bolding text by drawing twice, need to
 // render using a pixel offset in device pixels, otherwise text
 // doesn't appear bolded, it appears as if a bad text shadow exists
 // when a non-identity transform exists.  Use an offset factor so that
 // the second draw occurs at a constant offset in device pixels.
 double
 gfxFont::CalcXScale(gfxContext *aContext)
 {
     // determine magnitude of a 1px x offset in device space
     gfxSize t = aContext->UserToDevice(gfxSize(1.0, 0.0));
     if (t.width == 1.0 && t.height == 0.0) {
         // short-circuit the most common case to avoid sqrt() and division
         return 1.0;
     }
     double m = sqrt(t.width * t.width + t.height * t.height);
     NS_ASSERTION(m != 0.0, "degenerate transform while synthetic bolding");
     if (m == 0.0) {
         return 0.0; // effectively disables offset
     }
     // scale factor so that offsets are 1px in device pixels
     return 1.0 / m;
 }
 static DrawMode
 ForcePaintingDrawMode(DrawMode aDrawMode)
 {
     return aDrawMode == DrawMode::GLYPH_PATH ?
         DrawMode(int(DrawMode::GLYPH_FILL) | int(DrawMode::GLYPH_STROKE)) :
         aDrawMode;
 }
 void
 gfxFont::Draw(gfxTextRun *aTextRun, uint32_t aStart, uint32_t aEnd,
               gfxContext *aContext, DrawMode aDrawMode, gfxPoint *aPt,
               Spacing *aSpacing, gfxTextContextPaint *aContextPaint,
               gfxTextRunDrawCallbacks *aCallbacks)
 {
     NS_ASSERTION(aDrawMode == DrawMode::GLYPH_PATH || !(int(aDrawMode) & int(DrawMode::GLYPH_PATH)),
                  "GLYPH_PATH cannot be used with GLYPH_FILL, GLYPH_STROKE or GLYPH_STROKE_UNDERNEATH");
     if (aStart >= aEnd)
         return;
     const gfxTextRun::CompressedGlyph *charGlyphs = aTextRun->GetCharacterGlyphs();
     const int32_t appUnitsPerDevUnit = aTextRun->GetAppUnitsPerDevUnit();
     const double devUnitsPerAppUnit = 1.0/double(appUnitsPerDevUnit);
     bool isRTL = aTextRun->IsRightToLeft();
     double direction = aTextRun->GetDirection();
     gfxMatrix globalMatrix = aContext->CurrentMatrix();
     bool haveSVGGlyphs = GetFontEntry()->TryGetSVGData(this);
     nsAutoPtr<gfxTextContextPaint> contextPaint;
     if (haveSVGGlyphs && !aContextPaint) {
         // If no pattern is specified for fill, use the current pattern
         NS_ASSERTION((int(aDrawMode) & int(DrawMode::GLYPH_STROKE)) == 0, "no pattern supplied for stroking text");
         nsRefPtr<gfxPattern> fillPattern = aContext->GetPattern();
         contextPaint = new SimpleTextContextPaint(fillPattern, nullptr,
                                                  aContext->CurrentMatrix());
         aContextPaint = contextPaint;
     }
     // synthetic-bold strikes are each offset one device pixel in run direction
     // (these values are only needed if IsSyntheticBold() is true)
     double synBoldOnePixelOffset = 0;
     int32_t strikes = 1;
     if (IsSyntheticBold()) {
         double xscale = CalcXScale(aContext);
         synBoldOnePixelOffset = direction * xscale;
         if (xscale != 0.0) {
             // use as many strikes as needed for the the increased advance
             strikes = NS_lroundf(GetSyntheticBoldOffset() / xscale);
         }
     }
     uint32_t i;
     // Current position in appunits
     double x = aPt->x;
     double y = aPt->y;
     cairo_t *cr = aContext->GetCairo();
     RefPtr<DrawTarget> dt = aContext->GetDrawTarget();
     bool paintSVGGlyphs = !aCallbacks || aCallbacks->mShouldPaintSVGGlyphs;
     bool emittedGlyphs = false;
     if (aContext->IsCairo()) {
       bool success = SetupCairoFont(aContext);
       if (MOZ_UNLIKELY(!success))
           return;
       ::GlyphBuffer glyphs;
       cairo_glyph_t *glyph;
       if (aSpacing) {
           x += direction*aSpacing[0].mBefore;
       }
       for (i = aStart; i < aEnd; ++i) {
           const gfxTextRun::CompressedGlyph *glyphData = &charGlyphs[i];
           if (glyphData->IsSimpleGlyph()) {
               double advance = glyphData->GetSimpleAdvance();
               double glyphX;
               if (isRTL) {
                   x -= advance;
                   glyphX = x;
               } else {
                   glyphX = x;
                   x += advance;
               }
               if (haveSVGGlyphs) {
                   if (!paintSVGGlyphs) {
                       continue;
                   }
                   gfxPoint point(ToDeviceUnits(glyphX, devUnitsPerAppUnit),
                                  ToDeviceUnits(y, devUnitsPerAppUnit));
                   DrawMode mode = ForcePaintingDrawMode(aDrawMode);
                   if (RenderSVGGlyph(aContext, point, mode,
                                      glyphData->GetSimpleGlyph(), aContextPaint,
                                      aCallbacks, emittedGlyphs)) {
                       continue;
                   }
               }
               // Perhaps we should put a scale in the cairo context instead of
               // doing this scaling here...
               // Multiplying by the reciprocal may introduce tiny error here,
               // but we assume cairo is going to round coordinates at some stage
               // and this is faster
               glyph = glyphs.AppendGlyph();
               glyph->index = glyphData->GetSimpleGlyph();
               glyph->x = ToDeviceUnits(glyphX, devUnitsPerAppUnit);
               glyph->y = ToDeviceUnits(y, devUnitsPerAppUnit);
               glyphs.Flush(cr, aDrawMode, isRTL, aContextPaint, globalMatrix);
               // synthetic bolding by multi-striking with 1-pixel offsets
               // at least once, more if there's room (large font sizes)
               if (IsSyntheticBold()) {
                   double strikeOffset = synBoldOnePixelOffset;
                   int32_t strikeCount = strikes;
                   do {
                       cairo_glyph_t *doubleglyph;
                       doubleglyph = glyphs.AppendGlyph();
                       doubleglyph->index = glyph->index;
                       doubleglyph->x =
                           ToDeviceUnits(glyphX + strikeOffset * appUnitsPerDevUnit,
                                         devUnitsPerAppUnit);
                       doubleglyph->y = glyph->y;
                       strikeOffset += synBoldOnePixelOffset;
                       glyphs.Flush(cr, aDrawMode, isRTL, aContextPaint, globalMatrix);
                   } while (--strikeCount > 0);
               }
               emittedGlyphs = true;
           } else {
               uint32_t glyphCount = glyphData->GetGlyphCount();
               if (glyphCount > 0) {
                   const gfxTextRun::DetailedGlyph *details =
                       aTextRun->GetDetailedGlyphs(i);
                   NS_ASSERTION(details, "detailedGlyph should not be missing!");
                   double advance;
                   for (uint32_t j = 0; j < glyphCount; ++j, ++details, x += direction * advance) {
                       advance = details->mAdvance;
                       if (glyphData->IsMissing()) {
                           // default ignorable characters will have zero advance width.
                           // we don't have to draw the hexbox for them
                           if (aDrawMode != DrawMode::GLYPH_PATH && advance > 0) {
                               double glyphX = x;
                               if (isRTL) {
                                   glyphX -= advance;
                               }
                               gfxPoint pt(ToDeviceUnits(glyphX, devUnitsPerAppUnit),
                                           ToDeviceUnits(y, devUnitsPerAppUnit));
                               gfxFloat advanceDevUnits = ToDeviceUnits(advance, devUnitsPerAppUnit);
                               gfxFloat height = GetMetrics().maxAscent;
                               gfxRect glyphRect(pt.x, pt.y - height, advanceDevUnits, height);
                               gfxFontMissingGlyphs::DrawMissingGlyph(aContext,
                                                                      glyphRect,
                                                                      details->mGlyphID,
                                                                      appUnitsPerDevUnit);
                           }
                       } else {
                           double glyphX = x + details->mXOffset;
                           if (isRTL) {
                               glyphX -= advance;
                           }
                           gfxPoint point(ToDeviceUnits(glyphX, devUnitsPerAppUnit),
                                          ToDeviceUnits(y, devUnitsPerAppUnit));
                           if (haveSVGGlyphs) {
                               if (!paintSVGGlyphs) {
                                   continue;
                               }
                               DrawMode mode = ForcePaintingDrawMode(aDrawMode);
                               if (RenderSVGGlyph(aContext, point, mode,
                                                   details->mGlyphID,
                                                   aContextPaint, aCallbacks,
                                                   emittedGlyphs)) {
                                   continue;
                               }
                           }
                           glyph = glyphs.AppendGlyph();
                           glyph->index = details->mGlyphID;
                           glyph->x = ToDeviceUnits(glyphX, devUnitsPerAppUnit);
                           glyph->y = ToDeviceUnits(y + details->mYOffset, devUnitsPerAppUnit);
                           glyphs.Flush(cr, aDrawMode, isRTL, aContextPaint, globalMatrix);
                           if (IsSyntheticBold()) {
                               double strikeOffset = synBoldOnePixelOffset;
                               int32_t strikeCount = strikes;
                               do {
                                   cairo_glyph_t *doubleglyph;
                                   doubleglyph = glyphs.AppendGlyph();
                                   doubleglyph->index = glyph->index;
                                   doubleglyph->x =
                                       ToDeviceUnits(glyphX + strikeOffset *
                                               appUnitsPerDevUnit,
                                               devUnitsPerAppUnit);
                                   doubleglyph->y = glyph->y;
                                   strikeOffset += synBoldOnePixelOffset;
                                   glyphs.Flush(cr, aDrawMode, isRTL, aContextPaint, globalMatrix);
                               } while (--strikeCount > 0);
                           }
                           emittedGlyphs = true;
                       }
                   }
               }
           }
           if (aSpacing) {
               double space = aSpacing[i - aStart].mAfter;
               if (i + 1 < aEnd) {
                   space += aSpacing[i + 1 - aStart].mBefore;
               }
               x += direction*space;
           }
       }
       if (gfxFontTestStore::CurrentStore()) {
           /* This assumes that the tests won't have anything that results
            * in more than GLYPH_BUFFER_SIZE glyphs.  Do this before we
            * flush, since that'll blow away the num_glyphs.
            */
           gfxFontTestStore::CurrentStore()->AddItem(GetName(),
                                                     glyphs.mGlyphBuffer,
                                                     glyphs.mNumGlyphs);
       }
       // draw any remaining glyphs
       glyphs.Flush(cr, aDrawMode, isRTL, aContextPaint, globalMatrix, true);
       if (aCallbacks && emittedGlyphs) {
           aCallbacks->NotifyGlyphPathEmitted();
       }
     } else {
       RefPtr<ScaledFont> scaledFont = GetScaledFont(dt);
       if (!scaledFont) {
         return;
       }
       bool oldSubpixelAA = dt->GetPermitSubpixelAA();
       if (!AllowSubpixelAA()) {
           dt->SetPermitSubpixelAA(false);
       }
       GlyphBufferAzure glyphs;
       Glyph *glyph;
       Matrix mat, matInv;
       Matrix oldMat = dt->GetTransform();
       // This is nullptr when we have inverse-transformed glyphs and we need
       // to transform the Brush inside flush.
       Matrix *passedInvMatrix = nullptr;
       RefPtr<GlyphRenderingOptions> renderingOptions =
         GetGlyphRenderingOptions();
       DrawOptions drawOptions;
       drawOptions.mAntialiasMode = Get2DAAMode(mAntialiasOption);
       // The cairo DrawTarget backend uses the cairo_scaled_font directly
       // and so has the font skew matrix applied already.
       if (mScaledFont &&
           dt->GetType() != BackendType::CAIRO) {
         cairo_matrix_t matrix;
         cairo_scaled_font_get_font_matrix(mScaledFont, &matrix);
         if (matrix.xy != 0) {
           // If this matrix applies a skew, which can happen when drawing
           // oblique fonts, we will set the DrawTarget matrix to apply the
           // skew. We'll need to move the glyphs by the inverse of the skew to
           // get the glyphs positioned correctly in the new device space
           // though, since the font matrix should only be applied to drawing
           // the glyphs, and not to their position.
           mat = ToMatrix(*reinterpret_cast<gfxMatrix*>(&matrix));
           mat._11 = mat._22 = 1.0;
           float adjustedSize = mAdjustedSize > 0 ? mAdjustedSize : GetStyle()->size;
           mat._21 /= adjustedSize;
           dt->SetTransform(mat * oldMat);
           matInv = mat;
           matInv.Invert();
           passedInvMatrix = &matInv;
         }
       }
       if (aSpacing) {
           x += direction*aSpacing[0].mBefore;
       }
       for (i = aStart; i < aEnd; ++i) {
           const gfxTextRun::CompressedGlyph *glyphData = &charGlyphs[i];
           if (glyphData->IsSimpleGlyph()) {
               double advance = glyphData->GetSimpleAdvance();
               double glyphX;
               if (isRTL) {
                   x -= advance;
                   glyphX = x;
               } else {
                   glyphX = x;
                   x += advance;
               }
               if (haveSVGGlyphs) {
                   if (!paintSVGGlyphs) {
                       continue;
                   }
                   gfxPoint point(ToDeviceUnits(glyphX, devUnitsPerAppUnit),
                                  ToDeviceUnits(y, devUnitsPerAppUnit));
                   DrawMode mode = ForcePaintingDrawMode(aDrawMode);
                   if (RenderSVGGlyph(aContext, point, mode,
                                      glyphData->GetSimpleGlyph(), aContextPaint,
                                      aCallbacks, emittedGlyphs)) {
                       continue;
                   }
               }
               // Perhaps we should put a scale in the cairo context instead of
               // doing this scaling here...
               // Multiplying by the reciprocal may introduce tiny error here,
               // but we assume cairo is going to round coordinates at some stage
               // and this is faster
               glyph = glyphs.AppendGlyph();
               glyph->mIndex = glyphData->GetSimpleGlyph();
               glyph->mPosition.x = ToDeviceUnits(glyphX, devUnitsPerAppUnit);
               glyph->mPosition.y = ToDeviceUnits(y, devUnitsPerAppUnit);
               glyph->mPosition = matInv * glyph->mPosition;
               glyphs.Flush(dt, aContextPaint, scaledFont,
                            aDrawMode, isRTL, renderingOptions,
                            aContext, passedInvMatrix,
                            drawOptions);
               // synthetic bolding by multi-striking with 1-pixel offsets
               // at least once, more if there's room (large font sizes)
               if (IsSyntheticBold()) {
                   double strikeOffset = synBoldOnePixelOffset;
                   int32_t strikeCount = strikes;
                   do {
                       Glyph *doubleglyph;
                       doubleglyph = glyphs.AppendGlyph();
                       doubleglyph->mIndex = glyph->mIndex;
                       doubleglyph->mPosition.x =
                           ToDeviceUnits(glyphX + strikeOffset * appUnitsPerDevUnit,
                                         devUnitsPerAppUnit);
                       doubleglyph->mPosition.y = glyph->mPosition.y;
                       doubleglyph->mPosition = matInv * doubleglyph->mPosition;
                       strikeOffset += synBoldOnePixelOffset;
                       glyphs.Flush(dt, aContextPaint, scaledFont,
                                    aDrawMode, isRTL, renderingOptions,
                                    aContext, passedInvMatrix,
                                    drawOptions);
                   } while (--strikeCount > 0);
               }
               emittedGlyphs = true;
           } else {
               uint32_t glyphCount = glyphData->GetGlyphCount();
               if (glyphCount > 0) {
                   const gfxTextRun::DetailedGlyph *details =
                       aTextRun->GetDetailedGlyphs(i);
                   NS_ASSERTION(details, "detailedGlyph should not be missing!");
                   double advance;
                   for (uint32_t j = 0; j < glyphCount; ++j, ++details, x += direction * advance) {
                       advance = details->mAdvance;
                       if (glyphData->IsMissing()) {
                           // default ignorable characters will have zero advance width.
                           // we don't have to draw the hexbox for them
                           if (aDrawMode != DrawMode::GLYPH_PATH && advance > 0) {
                               double glyphX = x;
                               if (isRTL) {
                                   glyphX -= advance;
                               }
                               gfxPoint pt(ToDeviceUnits(glyphX, devUnitsPerAppUnit),
                                           ToDeviceUnits(y, devUnitsPerAppUnit));
                               gfxFloat advanceDevUnits = ToDeviceUnits(advance, devUnitsPerAppUnit);
                               gfxFloat height = GetMetrics().maxAscent;
                               gfxRect glyphRect(pt.x, pt.y - height, advanceDevUnits, height);
                               gfxFontMissingGlyphs::DrawMissingGlyph(aContext,
                                                                      glyphRect,
                                                                      details->mGlyphID,
                                                                      appUnitsPerDevUnit);
                           }
                       } else {
                           double glyphX = x + details->mXOffset;
                           if (isRTL) {
                               glyphX -= advance;
                           }
                           gfxPoint point(ToDeviceUnits(glyphX, devUnitsPerAppUnit),
                                          ToDeviceUnits(y, devUnitsPerAppUnit));
                           if (haveSVGGlyphs) {
                               if (!paintSVGGlyphs) {
                                   continue;
                               }
                               DrawMode mode = ForcePaintingDrawMode(aDrawMode);
                               if (RenderSVGGlyph(aContext, point, mode,
                                                  details->mGlyphID,
                                                  aContextPaint, aCallbacks,
                                                  emittedGlyphs)) {
                                   continue;
                               }
                           }
                           glyph = glyphs.AppendGlyph();
                           glyph->mIndex = details->mGlyphID;
                           glyph->mPosition.x = ToDeviceUnits(glyphX, devUnitsPerAppUnit);
                           glyph->mPosition.y = ToDeviceUnits(y + details->mYOffset, devUnitsPerAppUnit);
                           glyph->mPosition = matInv * glyph->mPosition;
                           glyphs.Flush(dt, aContextPaint, scaledFont, aDrawMode,
                                        isRTL, renderingOptions, aContext, passedInvMatrix,
                                        drawOptions);
                           if (IsSyntheticBold()) {
                               double strikeOffset = synBoldOnePixelOffset;
                               int32_t strikeCount = strikes;
                               do {
                                   Glyph *doubleglyph;
                                   doubleglyph = glyphs.AppendGlyph();
                                   doubleglyph->mIndex = glyph->mIndex;
                                   doubleglyph->mPosition.x =
                                       ToDeviceUnits(glyphX + strikeOffset *
                                                     appUnitsPerDevUnit,
                                                     devUnitsPerAppUnit);
                                   doubleglyph->mPosition.y = glyph->mPosition.y;
                                   strikeOffset += synBoldOnePixelOffset;
                                   doubleglyph->mPosition = matInv * doubleglyph->mPosition;
                                   glyphs.Flush(dt, aContextPaint, scaledFont,
                                                aDrawMode, isRTL, renderingOptions,
                                                aContext, passedInvMatrix, drawOptions);
                               } while (--strikeCount > 0);
                           }
                           emittedGlyphs = true;
                       }
                   }
               }
           }
           if (aSpacing) {
               double space = aSpacing[i - aStart].mAfter;
               if (i + 1 < aEnd) {
                   space += aSpacing[i + 1 - aStart].mBefore;
               }
               x += direction*space;
           }
       }
       glyphs.Flush(dt, aContextPaint, scaledFont, aDrawMode, isRTL,
                    renderingOptions, aContext, passedInvMatrix,
                    drawOptions, true);
       if (aCallbacks && emittedGlyphs) {
           aCallbacks->NotifyGlyphPathEmitted();
       }
       dt->SetTransform(oldMat);
       dt->SetPermitSubpixelAA(oldSubpixelAA);
     }
     *aPt = gfxPoint(x, y);
 }
 bool
 gfxFont::RenderSVGGlyph(gfxContext *aContext, gfxPoint aPoint, DrawMode aDrawMode,
                         uint32_t aGlyphId, gfxTextContextPaint *aContextPaint)
 {
     if (!GetFontEntry()->HasSVGGlyph(aGlyphId)) {
         return false;
     }
     const gfxFloat devUnitsPerSVGUnit =
         GetAdjustedSize() / GetFontEntry()->UnitsPerEm();
     gfxContextMatrixAutoSaveRestore matrixRestore(aContext);
     aContext->Translate(gfxPoint(aPoint.x, aPoint.y));
     aContext->Scale(devUnitsPerSVGUnit, devUnitsPerSVGUnit);
     aContextPaint->InitStrokeGeometry(aContext, devUnitsPerSVGUnit);
     return GetFontEntry()->RenderSVGGlyph(aContext, aGlyphId, int(aDrawMode),
                                           aContextPaint);
 }
 bool
 gfxFont::RenderSVGGlyph(gfxContext *aContext, gfxPoint aPoint, DrawMode aDrawMode,
                         uint32_t aGlyphId, gfxTextContextPaint *aContextPaint,
                         gfxTextRunDrawCallbacks *aCallbacks,
                         bool& aEmittedGlyphs)
 {
     if (aCallbacks) {
         if (aEmittedGlyphs) {
             aCallbacks->NotifyGlyphPathEmitted();
             aEmittedGlyphs = false;
         }
         aCallbacks->NotifyBeforeSVGGlyphPainted();
     }
     bool rendered = RenderSVGGlyph(aContext, aPoint, aDrawMode, aGlyphId,
                                    aContextPaint);
     if (aCallbacks) {
         aCallbacks->NotifyAfterSVGGlyphPainted();
     }
     return rendered;
 }
 static void
 UnionRange(gfxFloat aX, gfxFloat* aDestMin, gfxFloat* aDestMax)
 {
     *aDestMin = std::min(*aDestMin, aX);
     *aDestMax = std::max(*aDestMax, aX);
 }
 // We get precise glyph extents if the textrun creator requested them, or
 // if the font is a user font --- in which case the author may be relying
 // on overflowing glyphs.
 static bool
 NeedsGlyphExtents(gfxFont *aFont, gfxTextRun *aTextRun)
 {
     return (aTextRun->GetFlags() & gfxTextRunFactory::TEXT_NEED_BOUNDING_BOX) ||
         aFont->GetFontEntry()->IsUserFont();
 }
 static bool
 NeedsGlyphExtents(gfxTextRun *aTextRun)
 {
     if (aTextRun->GetFlags() & gfxTextRunFactory::TEXT_NEED_BOUNDING_BOX)
         return true;
     uint32_t numRuns;
     const gfxTextRun::GlyphRun *glyphRuns = aTextRun->GetGlyphRuns(&numRuns);
     for (uint32_t i = 0; i < numRuns; ++i) {
         if (glyphRuns[i].mFont->GetFontEntry()->IsUserFont())
             return true;
     }
     return false;
 }
 gfxFont::RunMetrics
 gfxFont::Measure(gfxTextRun *aTextRun,
                  uint32_t aStart, uint32_t aEnd,
                  BoundingBoxType aBoundingBoxType,
                  gfxContext *aRefContext,
                  Spacing *aSpacing)
 {
     // If aBoundingBoxType is TIGHT_HINTED_OUTLINE_EXTENTS
     // and the underlying cairo font may be antialiased,
     // we need to create a copy in order to avoid getting cached extents.
     // This is only used by MathML layout at present.
     if (aBoundingBoxType == TIGHT_HINTED_OUTLINE_EXTENTS &&
         mAntialiasOption != kAntialiasNone) {
         if (!mNonAAFont) {
             mNonAAFont = CopyWithAntialiasOption(kAntialiasNone);
         }
         // if font subclass doesn't implement CopyWithAntialiasOption(),
         // it will return null and we'll proceed to use the existing font
         if (mNonAAFont) {
             return mNonAAFont->Measure(aTextRun, aStart, aEnd,
                                        TIGHT_HINTED_OUTLINE_EXTENTS,
                                        aRefContext, aSpacing);
         }
     }
     const int32_t appUnitsPerDevUnit = aTextRun->GetAppUnitsPerDevUnit();
     // Current position in appunits
     const gfxFont::Metrics& fontMetrics = GetMetrics();
     RunMetrics metrics;
     metrics.mAscent = fontMetrics.maxAscent*appUnitsPerDevUnit;
     metrics.mDescent = fontMetrics.maxDescent*appUnitsPerDevUnit;
     if (aStart == aEnd) {
         // exit now before we look at aSpacing[0], which is undefined
         metrics.mBoundingBox = gfxRect(0, -metrics.mAscent, 0, metrics.mAscent + metrics.mDescent);
         return metrics;
     }
     gfxFloat advanceMin = 0, advanceMax = 0;
     const gfxTextRun::CompressedGlyph *charGlyphs = aTextRun->GetCharacterGlyphs();
     bool isRTL = aTextRun->IsRightToLeft();
     double direction = aTextRun->GetDirection();
     bool needsGlyphExtents = NeedsGlyphExtents(this, aTextRun);
     gfxGlyphExtents *extents =
         (aBoundingBoxType == LOOSE_INK_EXTENTS &&
             !needsGlyphExtents &&
             !aTextRun->HasDetailedGlyphs()) ? nullptr
         : GetOrCreateGlyphExtents(aTextRun->GetAppUnitsPerDevUnit());
     double x = 0;
     if (aSpacing) {
         x += direction*aSpacing[0].mBefore;
     }
     uint32_t i;
     for (i = aStart; i < aEnd; ++i) {
         const gfxTextRun::CompressedGlyph *glyphData = &charGlyphs[i];
         if (glyphData->IsSimpleGlyph()) {
             double advance = glyphData->GetSimpleAdvance();
             // Only get the real glyph horizontal extent if we were asked
             // for the tight bounding box or we're in quality mode
             if ((aBoundingBoxType != LOOSE_INK_EXTENTS || needsGlyphExtents) &&
                 extents) {
                 uint32_t glyphIndex = glyphData->GetSimpleGlyph();
                 uint16_t extentsWidth = extents->GetContainedGlyphWidthAppUnits(glyphIndex);
                 if (extentsWidth != gfxGlyphExtents::INVALID_WIDTH &&
                     aBoundingBoxType == LOOSE_INK_EXTENTS) {
                     UnionRange(x, &advanceMin, &advanceMax);
                     UnionRange(x + direction*extentsWidth, &advanceMin, &advanceMax);
                 } else {
                     gfxRect glyphRect;
                     if (!extents->GetTightGlyphExtentsAppUnits(this,
                             aRefContext, glyphIndex, &glyphRect)) {
                         glyphRect = gfxRect(0, metrics.mBoundingBox.Y(),
                             advance, metrics.mBoundingBox.Height());
                     }
                     if (isRTL) {
                         glyphRect -= gfxPoint(advance, 0);
                     }
                     glyphRect += gfxPoint(x, 0);
                     metrics.mBoundingBox = metrics.mBoundingBox.Union(glyphRect);
                 }
             }
             x += direction*advance;
         } else {
             uint32_t glyphCount = glyphData->GetGlyphCount();
             if (glyphCount > 0) {
                 const gfxTextRun::DetailedGlyph *details =
                     aTextRun->GetDetailedGlyphs(i);
                 NS_ASSERTION(details != nullptr,
                              "detaiedGlyph record should not be missing!");
                 uint32_t j;
                 for (j = 0; j < glyphCount; ++j, ++details) {
                     uint32_t glyphIndex = details->mGlyphID;
                     gfxPoint glyphPt(x + details->mXOffset, details->mYOffset);
                     double advance = details->mAdvance;
                     gfxRect glyphRect;
                     if (glyphData->IsMissing() || !extents ||
                         !extents->GetTightGlyphExtentsAppUnits(this,
                                 aRefContext, glyphIndex, &glyphRect)) {
                         // We might have failed to get glyph extents due to
                         // OOM or something
                         glyphRect = gfxRect(0, -metrics.mAscent,
                             advance, metrics.mAscent + metrics.mDescent);
                     }
                     if (isRTL) {
                         glyphRect -= gfxPoint(advance, 0);
                     }
                     glyphRect += gfxPoint(x, 0);
                     metrics.mBoundingBox = metrics.mBoundingBox.Union(glyphRect);
                     x += direction*advance;
                 }
             }
         }
         // Every other glyph type is ignored
         if (aSpacing) {
             double space = aSpacing[i - aStart].mAfter;
             if (i + 1 < aEnd) {
                 space += aSpacing[i + 1 - aStart].mBefore;
             }
             x += direction*space;
         }
     }
     if (aBoundingBoxType == LOOSE_INK_EXTENTS) {
         UnionRange(x, &advanceMin, &advanceMax);
         gfxRect fontBox(advanceMin, -metrics.mAscent,
                         advanceMax - advanceMin, metrics.mAscent + metrics.mDescent);
         metrics.mBoundingBox = metrics.mBoundingBox.Union(fontBox);
     }
     if (isRTL) {
         metrics.mBoundingBox -= gfxPoint(x, 0);
     }
     metrics.mAdvanceWidth = x*direction;
     return metrics;
 }
 static PLDHashOperator
 NotifyGlyphChangeObservers(nsPtrHashKey<gfxFont::GlyphChangeObserver>* aKey,
                            void* aClosure)
 {
     aKey->GetKey()->NotifyGlyphsChanged();
     return PL_DHASH_NEXT;
 }
 void
 gfxFont::NotifyGlyphsChanged()
 {
     uint32_t i, count = mGlyphExtentsArray.Length();
     for (i = 0; i < count; ++i) {
         // Flush cached extents array
         mGlyphExtentsArray[i]->NotifyGlyphsChanged();
     }
     if (mGlyphChangeObservers) {
         mGlyphChangeObservers->EnumerateEntries(NotifyGlyphChangeObservers, nullptr);
     }
 }
 static bool
 IsBoundarySpace(char16_t aChar, char16_t aNextChar)
 {
     return (aChar == ' ' || aChar == 0x00A0) && !IsClusterExtender(aNextChar);
 }
 static inline uint32_t
 HashMix(uint32_t aHash, char16_t aCh)
 {
     return (aHash >> 28) ^ (aHash << 4) ^ aCh;
 }
 #ifdef __GNUC__
 #define GFX_MAYBE_UNUSED __attribute__((unused))
 #else
 #define GFX_MAYBE_UNUSED
 #endif
 template<typename T>
 gfxShapedWord*
 gfxFont::GetShapedWord(gfxContext *aContext,
                        const T    *aText,
                        uint32_t    aLength,
                        uint32_t    aHash,
                        int32_t     aRunScript,
                        int32_t     aAppUnitsPerDevUnit,
                        uint32_t    aFlags,
                        gfxTextPerfMetrics *aTextPerf GFX_MAYBE_UNUSED)
 {
     // if the cache is getting too big, flush it and start over
     uint32_t wordCacheMaxEntries =
         gfxPlatform::GetPlatform()->WordCacheMaxEntries();
     if (mWordCache->Count() > wordCacheMaxEntries) {
         NS_WARNING("flushing shaped-word cache");
         ClearCachedWords();
     }
     // if there's a cached entry for this word, just return it
     CacheHashKey key(aText, aLength, aHash,
                      aRunScript,
                      aAppUnitsPerDevUnit,
                      aFlags);
     CacheHashEntry *entry = mWordCache->PutEntry(key);
     if (!entry) {
         NS_WARNING("failed to create word cache entry - expect missing text");
         return nullptr;
     }
     gfxShapedWord *sw = entry->mShapedWord;
     bool isContent = !mStyle.systemFont;
     if (sw) {
         sw->ResetAge();
         Telemetry::Accumulate((isContent ? Telemetry::WORD_CACHE_HITS_CONTENT :
                                    Telemetry::WORD_CACHE_HITS_CHROME),
                               aLength);
 #ifndef RELEASE_BUILD
         if (aTextPerf) {
             aTextPerf->current.wordCacheHit++;
         }
 #endif
         return sw;
     }
     Telemetry::Accumulate((isContent ? Telemetry::WORD_CACHE_MISSES_CONTENT :
                                Telemetry::WORD_CACHE_MISSES_CHROME),
                           aLength);
 #ifndef RELEASE_BUILD
     if (aTextPerf) {
         aTextPerf->current.wordCacheMiss++;
     }
 #endif
     sw = entry->mShapedWord = gfxShapedWord::Create(aText, aLength,
                                                     aRunScript,
                                                     aAppUnitsPerDevUnit,
                                                     aFlags);
     if (!sw) {
         NS_WARNING("failed to create gfxShapedWord - expect missing text");
         return nullptr;
     }
     DebugOnly<bool> ok =
         ShapeText(aContext, aText, 0, aLength, aRunScript, sw);
     NS_WARN_IF_FALSE(ok, "failed to shape word - expect garbled text");
     return sw;
 }
 bool
 gfxFont::CacheHashEntry::KeyEquals(const KeyTypePointer aKey) const
 {
     const gfxShapedWord *sw = mShapedWord;
     if (!sw) {
         return false;
     }
     if (sw->GetLength() != aKey->mLength ||
         sw->Flags() != aKey->mFlags ||
         sw->GetAppUnitsPerDevUnit() != aKey->mAppUnitsPerDevUnit ||
         sw->Script() != aKey->mScript) {
         return false;
     }
     if (sw->TextIs8Bit()) {
         if (aKey->mTextIs8Bit) {
             return (0 == memcmp(sw->Text8Bit(), aKey->mText.mSingle,
                                 aKey->mLength * sizeof(uint8_t)));
         }
         // The key has 16-bit text, even though all the characters are < 256,
         // so the TEXT_IS_8BIT flag was set and the cached ShapedWord we're
         // comparing with will have 8-bit text.
         const uint8_t   *s1 = sw->Text8Bit();
         const char16_t *s2 = aKey->mText.mDouble;
         const char16_t *s2end = s2 + aKey->mLength;
         while (s2 < s2end) {
             if (*s1++ != *s2++) {
                 return false;
             }
         }
         return true;
     }
     NS_ASSERTION((aKey->mFlags & gfxTextRunFactory::TEXT_IS_8BIT) == 0 &&
                  !aKey->mTextIs8Bit, "didn't expect 8-bit text here");
     return (0 == memcmp(sw->TextUnicode(), aKey->mText.mDouble,
                         aKey->mLength * sizeof(char16_t)));
 }
 bool
 gfxFont::ShapeText(gfxContext    *aContext,
                    const uint8_t *aText,
                    uint32_t       aOffset,
                    uint32_t       aLength,
                    int32_t        aScript,
                    gfxShapedText *aShapedText,
                    bool           aPreferPlatformShaping)
 {
     nsDependentCSubstring ascii((const char*)aText, aLength);
     nsAutoString utf16;
     AppendASCIItoUTF16(ascii, utf16);
     if (utf16.Length() != aLength) {
         return false;
     }
     return ShapeText(aContext, utf16.BeginReading(), aOffset, aLength,
                      aScript, aShapedText, aPreferPlatformShaping);
 }
 bool
 gfxFont::ShapeText(gfxContext      *aContext,
                    const char16_t *aText,
                    uint32_t         aOffset,
                    uint32_t         aLength,
                    int32_t          aScript,
                    gfxShapedText   *aShapedText,
                    bool             aPreferPlatformShaping)
 {
     bool ok = false;
     if (mGraphiteShaper && gfxPlatform::GetPlatform()->UseGraphiteShaping()) {
         ok = mGraphiteShaper->ShapeText(aContext, aText, aOffset, aLength,
                                         aScript, aShapedText);
     }
     if (!ok && mHarfBuzzShaper && !aPreferPlatformShaping) {
         if (gfxPlatform::GetPlatform()->UseHarfBuzzForScript(aScript)) {
             ok = mHarfBuzzShaper->ShapeText(aContext, aText, aOffset, aLength,
                                             aScript, aShapedText);
         }
     }
     if (!ok) {
         if (!mPlatformShaper) {
             CreatePlatformShaper();
             NS_ASSERTION(mPlatformShaper, "no platform shaper available!");
         }
         if (mPlatformShaper) {
             ok = mPlatformShaper->ShapeText(aContext, aText, aOffset, aLength,
                                             aScript, aShapedText);
         }
     }
     PostShapingFixup(aContext, aText, aOffset, aLength, aShapedText);
     return ok;
 }
 void
 gfxFont::PostShapingFixup(gfxContext      *aContext,
                           const char16_t *aText,
                           uint32_t         aOffset,
                           uint32_t         aLength,
                           gfxShapedText   *aShapedText)
 {
     if (IsSyntheticBold()) {
         float synBoldOffset =
                 GetSyntheticBoldOffset() * CalcXScale(aContext);
         aShapedText->AdjustAdvancesForSyntheticBold(synBoldOffset,
                                                     aOffset, aLength);
     }
 }
 #define MAX_SHAPING_LENGTH  32760 // slightly less than 32K, trying to avoid
                                   // over-stressing platform shapers
 #define BACKTRACK_LIMIT     16 // backtrack this far looking for a good place
                                // to split into fragments for separate shaping
 template<typename T>
 bool
 gfxFont::ShapeFragmentWithoutWordCache(gfxContext *aContext,
                                        const T    *aText,
                                        uint32_t    aOffset,
                                        uint32_t    aLength,
                                        int32_t     aScript,
                                        gfxTextRun *aTextRun)
 {
     aTextRun->SetupClusterBoundaries(aOffset, aText, aLength);
     bool ok = true;
     while (ok && aLength > 0) {
         uint32_t fragLen = aLength;
         // limit the length of text we pass to shapers in a single call
         if (fragLen > MAX_SHAPING_LENGTH) {
             fragLen = MAX_SHAPING_LENGTH;
             // in the 8-bit case, there are no multi-char clusters,
             // so we don't need to do this check
             if (sizeof(T) == sizeof(char16_t)) {
                 uint32_t i;
                 for (i = 0; i < BACKTRACK_LIMIT; ++i) {
                     if (aTextRun->IsClusterStart(aOffset + fragLen - i)) {
                         fragLen -= i;
                         break;
                     }
                 }
                 if (i == BACKTRACK_LIMIT) {
                     // if we didn't find any cluster start while backtracking,
                     // just check that we're not in the middle of a surrogate
                     // pair; back up by one code unit if we are.
                     if (NS_IS_LOW_SURROGATE(aText[fragLen]) &&
                         NS_IS_HIGH_SURROGATE(aText[fragLen - 1])) {
                         --fragLen;
                     }
                 }
             }
         }
         ok = ShapeText(aContext, aText, aOffset, fragLen, aScript, aTextRun);
         aText += fragLen;
         aOffset += fragLen;
         aLength -= fragLen;
     }
     return ok;
 }
 // Check if aCh is an unhandled control character that should be displayed
 // as a hexbox rather than rendered by some random font on the system.
 // We exclude \r as stray &#13;s are rather common (bug 941940).
 // Note that \n and \t don't come through here, as they have specific
 // meanings that have already been handled.
 static bool
 IsInvalidControlChar(uint32_t aCh)
 {
     return aCh != '\r' && ((aCh & 0x7f) < 0x20 || aCh == 0x7f);
 }
 template<typename T>
 bool
 gfxFont::ShapeTextWithoutWordCache(gfxContext *aContext,
                                    const T    *aText,
                                    uint32_t    aOffset,
                                    uint32_t    aLength,
                                    int32_t     aScript,
                                    gfxTextRun *aTextRun)
 {
     uint32_t fragStart = 0;
     bool ok = true;
     for (uint32_t i = 0; i <= aLength && ok; ++i) {
         T ch = (i < aLength) ? aText[i] : '\n';
         bool invalid = gfxFontGroup::IsInvalidChar(ch);
         uint32_t length = i - fragStart;
         // break into separate fragments when we hit an invalid char
         if (!invalid) {
             continue;
         }
         if (length > 0) {
             ok = ShapeFragmentWithoutWordCache(aContext, aText + fragStart,
                                                aOffset + fragStart, length,
                                                aScript, aTextRun);
         }
         if (i == aLength) {
             break;
         }
         // fragment was terminated by an invalid char: skip it,
         // unless it's a control char that we want to show as a hexbox,
         // but record where TAB or NEWLINE occur
         if (ch == '\t') {
             aTextRun->SetIsTab(aOffset + i);
         } else if (ch == '\n') {
             aTextRun->SetIsNewline(aOffset + i);
         } else if (IsInvalidControlChar(ch) &&
             !(aTextRun->GetFlags() & gfxTextRunFactory::TEXT_HIDE_CONTROL_CHARACTERS)) {
             aTextRun->SetMissingGlyph(aOffset + i, ch, this);
         }
         fragStart = i + 1;
     }
     NS_WARN_IF_FALSE(ok, "failed to shape text - expect garbled text");
     return ok;
 }
 #ifndef RELEASE_BUILD
 #define TEXT_PERF_INCR(tp, m) (tp ? (tp)->current.m++ : 0)
 #else
 #define TEXT_PERF_INCR(tp, m)
 #endif
 inline static bool IsChar8Bit(uint8_t /*aCh*/) { return true; }
 inline static bool IsChar8Bit(char16_t aCh) { return aCh < 0x100; }
 inline static bool HasSpaces(const uint8_t *aString, uint32_t aLen)
 {
     return memchr(aString, 0x20, aLen) != nullptr;
 }
 inline static bool HasSpaces(const char16_t *aString, uint32_t aLen)
 {
     for (const char16_t *ch = aString; ch < aString + aLen; ch++) {
         if (*ch == 0x20) {
             return true;
         }
     }
     return false;
 }
 template<typename T>
 bool
 gfxFont::SplitAndInitTextRun(gfxContext *aContext,
                              gfxTextRun *aTextRun,
                              const T *aString,
                              uint32_t aRunStart,
                              uint32_t aRunLength,
                              int32_t aRunScript)
 {
     if (aRunLength == 0) {
         return true;
     }
     gfxTextPerfMetrics *tp = nullptr;
 #ifndef RELEASE_BUILD
     tp = aTextRun->GetFontGroup()->GetTextPerfMetrics();
     if (tp) {
         if (mStyle.systemFont) {
             tp->current.numChromeTextRuns++;
         } else {
             tp->current.numContentTextRuns++;
         }
         tp->current.numChars += aRunLength;
         if (aRunLength > tp->current.maxTextRunLen) {
             tp->current.maxTextRunLen = aRunLength;
         }
     }
 #endif
     uint32_t wordCacheCharLimit =
         gfxPlatform::GetPlatform()->WordCacheCharLimit();
     // If spaces can participate in shaping (e.g. within lookups for automatic
     // fractions), need to shape without using the word cache which segments
     // textruns on space boundaries. Word cache can be used if the textrun
     // is short enough to fit in the word cache and it lacks spaces.
     if (SpaceMayParticipateInShaping(aRunScript)) {
         if (aRunLength > wordCacheCharLimit ||
             HasSpaces(aString + aRunStart, aRunLength)) {
             TEXT_PERF_INCR(tp, wordCacheSpaceRules);
             return ShapeTextWithoutWordCache(aContext, aString + aRunStart,
                                              aRunStart, aRunLength, aRunScript,
                                              aTextRun);
         }
     }
     InitWordCache();
     // the only flags we care about for ShapedWord construction/caching
     uint32_t flags = aTextRun->GetFlags();
     flags &= (gfxTextRunFactory::TEXT_IS_RTL |
               gfxTextRunFactory::TEXT_DISABLE_OPTIONAL_LIGATURES |
               gfxTextRunFactory::TEXT_USE_MATH_SCRIPT);
     if (sizeof(T) == sizeof(uint8_t)) {
         flags |= gfxTextRunFactory::TEXT_IS_8BIT;
     }
     const T *text = aString + aRunStart;
     uint32_t wordStart = 0;
     uint32_t hash = 0;
     bool wordIs8Bit = true;
     int32_t appUnitsPerDevUnit = aTextRun->GetAppUnitsPerDevUnit();
     T nextCh = text[0];
     for (uint32_t i = 0; i <= aRunLength; ++i) {
         T ch = nextCh;
         nextCh = (i < aRunLength - 1) ? text[i + 1] : '\n';
         bool boundary = IsBoundarySpace(ch, nextCh);
         bool invalid = !boundary && gfxFontGroup::IsInvalidChar(ch);
         uint32_t length = i - wordStart;
         // break into separate ShapedWords when we hit an invalid char,
         // or a boundary space (always handled individually),
         // or the first non-space after a space
         if (!boundary && !invalid) {
             if (!IsChar8Bit(ch)) {
                 wordIs8Bit = false;
             }
             // include this character in the hash, and move on to next
             hash = HashMix(hash, ch);
             continue;
         }
         // We've decided to break here (i.e. we're at the end of a "word");
         // shape the word and add it to the textrun.
         // For words longer than the limit, we don't use the
         // font's word cache but just shape directly into the textrun.
         if (length > wordCacheCharLimit) {
             TEXT_PERF_INCR(tp, wordCacheLong);
             bool ok = ShapeFragmentWithoutWordCache(aContext,
                                                     text + wordStart,
                                                     aRunStart + wordStart,
                                                     length,
                                                     aRunScript,
                                                     aTextRun);
             if (!ok) {
                 return false;
             }
         } else if (length > 0) {
             uint32_t wordFlags = flags;
             // in the 8-bit version of this method, TEXT_IS_8BIT was
             // already set as part of |flags|, so no need for a per-word
             // adjustment here
             if (sizeof(T) == sizeof(char16_t)) {
                 if (wordIs8Bit) {
                     wordFlags |= gfxTextRunFactory::TEXT_IS_8BIT;
                 }
             }
             gfxShapedWord *sw = GetShapedWord(aContext,
                                               text + wordStart, length,
                                               hash, aRunScript,
                                               appUnitsPerDevUnit,
                                               wordFlags, tp);
             if (sw) {
                 aTextRun->CopyGlyphDataFrom(sw, aRunStart + wordStart);
             } else {
                 return false; // failed, presumably out of memory?
             }
         }
         if (boundary) {
             // word was terminated by a space: add that to the textrun
             if (!aTextRun->SetSpaceGlyphIfSimple(this, aContext,
                                                  aRunStart + i, ch))
             {
                 static const uint8_t space = ' ';
                 gfxShapedWord *sw =
                     GetShapedWord(aContext,
                                   &space, 1,
                                   HashMix(0, ' '), aRunScript,
                                   appUnitsPerDevUnit,
                                   flags | gfxTextRunFactory::TEXT_IS_8BIT, tp);
                 if (sw) {
                     aTextRun->CopyGlyphDataFrom(sw, aRunStart + i);
                 } else {
                     return false;
                 }
             }
             hash = 0;
             wordStart = i + 1;
             wordIs8Bit = true;
             continue;
         }
         if (i == aRunLength) {
             break;
         }
         NS_ASSERTION(invalid,
                      "how did we get here except via an invalid char?");
         // word was terminated by an invalid char: skip it,
         // unless it's a control char that we want to show as a hexbox,
         // but record where TAB or NEWLINE occur
         if (ch == '\t') {
             aTextRun->SetIsTab(aRunStart + i);
         } else if (ch == '\n') {
             aTextRun->SetIsNewline(aRunStart + i);
         } else if (IsInvalidControlChar(ch) &&
             !(aTextRun->GetFlags() & gfxTextRunFactory::TEXT_HIDE_CONTROL_CHARACTERS)) {
             aTextRun->SetMissingGlyph(aRunStart + i, ch, this);
         }
         hash = 0;
         wordStart = i + 1;
         wordIs8Bit = true;
     }
     return true;
 }
 gfxGlyphExtents *
 gfxFont::GetOrCreateGlyphExtents(int32_t aAppUnitsPerDevUnit) {
     uint32_t i, count = mGlyphExtentsArray.Length();
     for (i = 0; i < count; ++i) {
         if (mGlyphExtentsArray[i]->GetAppUnitsPerDevUnit() == aAppUnitsPerDevUnit)
             return mGlyphExtentsArray[i];
     }
     gfxGlyphExtents *glyphExtents = new gfxGlyphExtents(aAppUnitsPerDevUnit);
     if (glyphExtents) {
         mGlyphExtentsArray.AppendElement(glyphExtents);
         // Initialize the extents of a space glyph, assuming that spaces don't
         // render anything!
         glyphExtents->SetContainedGlyphWidthAppUnits(GetSpaceGlyph(), 0);
     }
     return glyphExtents;
 }
 void
 gfxFont::SetupGlyphExtents(gfxContext *aContext, uint32_t aGlyphID, bool aNeedTight,
                            gfxGlyphExtents *aExtents)
 {
     gfxContextMatrixAutoSaveRestore matrixRestore(aContext);
     aContext->IdentityMatrix();
     gfxRect svgBounds;
     if (mFontEntry->TryGetSVGData(this) && mFontEntry->HasSVGGlyph(aGlyphID) &&
         mFontEntry->GetSVGGlyphExtents(aContext, aGlyphID, &svgBounds)) {
         gfxFloat d2a = aExtents->GetAppUnitsPerDevUnit();
         aExtents->SetTightGlyphExtents(aGlyphID,
                                        gfxRect(svgBounds.x * d2a,
                                                svgBounds.y * d2a,
                                                svgBounds.width * d2a,
                                                svgBounds.height * d2a));
         return;
     }
     cairo_glyph_t glyph;
     glyph.index = aGlyphID;
     glyph.x = 0;
     glyph.y = 0;
     cairo_text_extents_t extents;
     cairo_glyph_extents(aContext->GetCairo(), &glyph, 1, &extents);
     const Metrics& fontMetrics = GetMetrics();
     int32_t appUnitsPerDevUnit = aExtents->GetAppUnitsPerDevUnit();
     if (!aNeedTight && extents.x_bearing >= 0 &&
         extents.y_bearing >= -fontMetrics.maxAscent &&
         extents.height + extents.y_bearing <= fontMetrics.maxDescent) {
         uint32_t appUnitsWidth =
             uint32_t(ceil((extents.x_bearing + extents.width)*appUnitsPerDevUnit));
         if (appUnitsWidth < gfxGlyphExtents::INVALID_WIDTH) {
             aExtents->SetContainedGlyphWidthAppUnits(aGlyphID, uint16_t(appUnitsWidth));
             return;
         }
     }
 #ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
     if (!aNeedTight) {
         ++gGlyphExtentsSetupFallBackToTight;
     }
 #endif
     gfxFloat d2a = appUnitsPerDevUnit;
     gfxRect bounds(extents.x_bearing*d2a, extents.y_bearing*d2a,
                    extents.width*d2a, extents.height*d2a);
     aExtents->SetTightGlyphExtents(aGlyphID, bounds);
 }
 // Try to initialize font metrics by reading sfnt tables directly;
 // set mIsValid=TRUE and return TRUE on success.
 // Return FALSE if the gfxFontEntry subclass does not
 // implement GetFontTable(), or for non-sfnt fonts where tables are
 // not available.
 // If this returns TRUE without setting the mIsValid flag, then we -did-
 // apparently find an sfnt, but it was too broken to be used.
 bool
 gfxFont::InitMetricsFromSfntTables(Metrics& aMetrics)
 {
     mIsValid = false; // font is NOT valid in case of early return
     const uint32_t kHheaTableTag = TRUETYPE_TAG('h','h','e','a');
     const uint32_t kPostTableTag = TRUETYPE_TAG('p','o','s','t');
     const uint32_t kOS_2TableTag = TRUETYPE_TAG('O','S','/','2');
     uint32_t len;
     if (mFUnitsConvFactor == 0.0) {
         // If the conversion factor from FUnits is not yet set,
         // get the unitsPerEm from the 'head' table via the font entry
         uint16_t unitsPerEm = GetFontEntry()->UnitsPerEm();
         if (unitsPerEm == gfxFontEntry::kInvalidUPEM) {
             return false;
         }
         mFUnitsConvFactor = mAdjustedSize / unitsPerEm;
     }
     // 'hhea' table is required to get vertical extents
     gfxFontEntry::AutoTable hheaTable(mFontEntry, kHheaTableTag);
     if (!hheaTable) {
         return false; // no 'hhea' table -> not an sfnt
     }
     const HheaTable* hhea =
         reinterpret_cast<const HheaTable*>(hb_blob_get_data(hheaTable, &len));
     if (len < sizeof(HheaTable)) {
         return false;
     }
 #define SET_UNSIGNED(field,src) aMetrics.field = uint16_t(src) * mFUnitsConvFactor
 #define SET_SIGNED(field,src)   aMetrics.field = int16_t(src) * mFUnitsConvFactor
     SET_UNSIGNED(maxAdvance, hhea->advanceWidthMax);
     SET_SIGNED(maxAscent, hhea->ascender);
     SET_SIGNED(maxDescent, -int16_t(hhea->descender));
     SET_SIGNED(externalLeading, hhea->lineGap);
     // 'post' table is required for underline metrics
     gfxFontEntry::AutoTable postTable(mFontEntry, kPostTableTag);
     if (!postTable) {
         return true; // no 'post' table -> sfnt is not valid
     }
     const PostTable *post =
         reinterpret_cast<const PostTable*>(hb_blob_get_data(postTable, &len));
     if (len < offsetof(PostTable, underlineThickness) + sizeof(uint16_t)) {
         return true; // bad post table -> sfnt is not valid
     }
     SET_SIGNED(underlineOffset, post->underlinePosition);
     SET_UNSIGNED(underlineSize, post->underlineThickness);
     // 'OS/2' table is optional, if not found we'll estimate xHeight
     // and aveCharWidth by measuring glyphs
     gfxFontEntry::AutoTable os2Table(mFontEntry, kOS_2TableTag);
     if (os2Table) {
         const OS2Table *os2 =
             reinterpret_cast<const OS2Table*>(hb_blob_get_data(os2Table, &len));
         if (len >= offsetof(OS2Table, sxHeight) + sizeof(int16_t) &&
             uint16_t(os2->version) >= 2) {
             // version 2 and later includes the x-height field
             SET_SIGNED(xHeight, os2->sxHeight);
             // Abs because of negative xHeight seen in Kokonor (Tibetan) font
             aMetrics.xHeight = Abs(aMetrics.xHeight);
         }
         // this should always be present in any valid OS/2 of any version
         if (len >= offsetof(OS2Table, sTypoLineGap) + sizeof(int16_t)) {
             SET_SIGNED(aveCharWidth, os2->xAvgCharWidth);
             SET_SIGNED(subscriptOffset, os2->ySubscriptYOffset);
             SET_SIGNED(superscriptOffset, os2->ySuperscriptYOffset);
             SET_SIGNED(strikeoutSize, os2->yStrikeoutSize);
             SET_SIGNED(strikeoutOffset, os2->yStrikeoutPosition);
             // for fonts with USE_TYPO_METRICS set in the fsSelection field,
             // and for all OpenType math fonts (having a 'MATH' table),
             // let the OS/2 sTypo* metrics override those from the hhea table
             // (see http://www.microsoft.com/typography/otspec/os2.htm#fss)
             const uint16_t kUseTypoMetricsMask = 1 << 7;
             if ((uint16_t(os2->fsSelection) & kUseTypoMetricsMask) ||
                 mFontEntry->HasFontTable(TRUETYPE_TAG('M','A','T','H'))) {
                 SET_SIGNED(maxAscent, os2->sTypoAscender);
                 SET_SIGNED(maxDescent, - int16_t(os2->sTypoDescender));
                 SET_SIGNED(externalLeading, os2->sTypoLineGap);
             }
         }
     }
     mIsValid = true;
     return true;
 }
 static double
 RoundToNearestMultiple(double aValue, double aFraction)
 {
     return floor(aValue/aFraction + 0.5) * aFraction;
 }
 void gfxFont::CalculateDerivedMetrics(Metrics& aMetrics)
 {
     aMetrics.maxAscent =
         ceil(RoundToNearestMultiple(aMetrics.maxAscent, 1/1024.0));
     aMetrics.maxDescent =
         ceil(RoundToNearestMultiple(aMetrics.maxDescent, 1/1024.0));
     if (aMetrics.xHeight <= 0) {
         // only happens if we couldn't find either font metrics
         // or a char to measure;
         // pick an arbitrary value that's better than zero
         aMetrics.xHeight = aMetrics.maxAscent * DEFAULT_XHEIGHT_FACTOR;
     }
     aMetrics.maxHeight = aMetrics.maxAscent + aMetrics.maxDescent;
     if (aMetrics.maxHeight - aMetrics.emHeight > 0.0) {
         aMetrics.internalLeading = aMetrics.maxHeight - aMetrics.emHeight;
     } else {
         aMetrics.internalLeading = 0.0;
     }
     aMetrics.emAscent = aMetrics.maxAscent * aMetrics.emHeight
                             / aMetrics.maxHeight;
     aMetrics.emDescent = aMetrics.emHeight - aMetrics.emAscent;
     if (GetFontEntry()->IsFixedPitch()) {
         // Some Quartz fonts are fixed pitch, but there's some glyph with a bigger
         // advance than the average character width... this forces
         // those fonts to be recognized like fixed pitch fonts by layout.
         aMetrics.maxAdvance = aMetrics.aveCharWidth;
     }
     if (!aMetrics.subscriptOffset) {
         aMetrics.subscriptOffset = aMetrics.xHeight;
     }
     if (!aMetrics.superscriptOffset) {
         aMetrics.superscriptOffset = aMetrics.xHeight;
     }
     if (!aMetrics.strikeoutOffset) {
         aMetrics.strikeoutOffset = aMetrics.xHeight * 0.5;
     }
     if (!aMetrics.strikeoutSize) {
         aMetrics.strikeoutSize = aMetrics.underlineSize;
     }
 }
 void
 gfxFont::SanitizeMetrics(gfxFont::Metrics *aMetrics, bool aIsBadUnderlineFont)
 {
     // Even if this font size is zero, this font is created with non-zero size.
     // However, for layout and others, we should return the metrics of zero size font.
     if (mStyle.size == 0.0) {
         memset(aMetrics, 0, sizeof(gfxFont::Metrics));
         return;
     }
     // MS (P)Gothic and MS (P)Mincho are not having suitable values in their super script offset.
     // If the values are not suitable, we should use x-height instead of them.
     // See https://bugzilla.mozilla.org/show_bug.cgi?id=353632
     if (aMetrics->superscriptOffset <= 0 ||
         aMetrics->superscriptOffset >= aMetrics->maxAscent) {
         aMetrics->superscriptOffset = aMetrics->xHeight;
     }
     // And also checking the case of sub script offset. The old gfx for win has checked this too.
     if (aMetrics->subscriptOffset <= 0 ||
         aMetrics->subscriptOffset >= aMetrics->maxAscent) {
         aMetrics->subscriptOffset = aMetrics->xHeight;
     }
     aMetrics->underlineSize = std::max(1.0, aMetrics->underlineSize);
     aMetrics->strikeoutSize = std::max(1.0, aMetrics->strikeoutSize);
     aMetrics->underlineOffset = std::min(aMetrics->underlineOffset, -1.0);
     if (aMetrics->maxAscent < 1.0) {
         // We cannot draw strikeout line and overline in the ascent...
         aMetrics->underlineSize = 0;
         aMetrics->underlineOffset = 0;
         aMetrics->strikeoutSize = 0;
         aMetrics->strikeoutOffset = 0;
         return;
     }
     /**
      * Some CJK fonts have bad underline offset. Therefore, if this is such font,
      * we need to lower the underline offset to bottom of *em* descent.
      * However, if this is system font, we should not do this for the rendering compatibility with
      * another application's UI on the platform.
      * XXX Should not use this hack if the font size is too small?
      *     Such text cannot be read, this might be used for tight CSS rendering? (E.g., Acid2)
      */
     if (!mStyle.systemFont && aIsBadUnderlineFont) {
         // First, we need 2 pixels between baseline and underline at least. Because many CJK characters
         // put their glyphs on the baseline, so, 1 pixel is too close for CJK characters.
         aMetrics->underlineOffset = std::min(aMetrics->underlineOffset, -2.0);
         // Next, we put the underline to bottom of below of the descent space.
         if (aMetrics->internalLeading + aMetrics->externalLeading > aMetrics->underlineSize) {
             aMetrics->underlineOffset = std::min(aMetrics->underlineOffset, -aMetrics->emDescent);
         } else {
             aMetrics->underlineOffset = std::min(aMetrics->underlineOffset,
                                                aMetrics->underlineSize - aMetrics->emDescent);
         }
     }
     // If underline positioned is too far from the text, descent position is preferred so that underline
     // will stay within the boundary.
     else if (aMetrics->underlineSize - aMetrics->underlineOffset > aMetrics->maxDescent) {
         if (aMetrics->underlineSize > aMetrics->maxDescent)
             aMetrics->underlineSize = std::max(aMetrics->maxDescent, 1.0);
         // The max underlineOffset is 1px (the min underlineSize is 1px, and min maxDescent is 0px.)
         aMetrics->underlineOffset = aMetrics->underlineSize - aMetrics->maxDescent;
     }
     // If strikeout line is overflowed from the ascent, the line should be resized and moved for
     // that being in the ascent space.
     // Note that the strikeoutOffset is *middle* of the strikeout line position.
     gfxFloat halfOfStrikeoutSize = floor(aMetrics->strikeoutSize / 2.0 + 0.5);
     if (halfOfStrikeoutSize + aMetrics->strikeoutOffset > aMetrics->maxAscent) {
         if (aMetrics->strikeoutSize > aMetrics->maxAscent) {
             aMetrics->strikeoutSize = std::max(aMetrics->maxAscent, 1.0);
             halfOfStrikeoutSize = floor(aMetrics->strikeoutSize / 2.0 + 0.5);
         }
         gfxFloat ascent = floor(aMetrics->maxAscent + 0.5);
         aMetrics->strikeoutOffset = std::max(halfOfStrikeoutSize, ascent / 2.0);
     }
     // If overline is larger than the ascent, the line should be resized.
     if (aMetrics->underlineSize > aMetrics->maxAscent) {
         aMetrics->underlineSize = aMetrics->maxAscent;
     }
 }
 gfxFloat
 gfxFont::SynthesizeSpaceWidth(uint32_t aCh)
 {
     // return an appropriate width for various Unicode space characters
     // that we "fake" if they're not actually present in the font;
     // returns negative value if the char is not a known space.
     switch (aCh) {
     case 0x2000:                                 // en quad
     case 0x2002: return GetAdjustedSize() / 2;   // en space
     case 0x2001:                                 // em quad
     case 0x2003: return GetAdjustedSize();       // em space
     case 0x2004: return GetAdjustedSize() / 3;   // three-per-em space
     case 0x2005: return GetAdjustedSize() / 4;   // four-per-em space
     case 0x2006: return GetAdjustedSize() / 6;   // six-per-em space
     case 0x2007: return GetMetrics().zeroOrAveCharWidth; // figure space
     case 0x2008: return GetMetrics().spaceWidth; // punctuation space
     case 0x2009: return GetAdjustedSize() / 5;   // thin space
     case 0x200a: return GetAdjustedSize() / 10;  // hair space
     case 0x202f: return GetAdjustedSize() / 5;   // narrow no-break space
     default: return -1.0;
     }
 }
 /*static*/ size_t
 gfxFont::WordCacheEntrySizeOfExcludingThis(CacheHashEntry*   aHashEntry,
                                            MallocSizeOf aMallocSizeOf,
                                            void*             aUserArg)
 {
     return aMallocSizeOf(aHashEntry->mShapedWord.get());
 }
 void
 gfxFont::AddSizeOfExcludingThis(MallocSizeOf aMallocSizeOf,
                                 FontCacheSizes* aSizes) const
 {
     for (uint32_t i = 0; i < mGlyphExtentsArray.Length(); ++i) {
         aSizes->mFontInstances +=
             mGlyphExtentsArray[i]->SizeOfIncludingThis(aMallocSizeOf);
     }
     if (mWordCache) {
         aSizes->mShapedWords +=
             mWordCache->SizeOfExcludingThis(WordCacheEntrySizeOfExcludingThis,
                                             aMallocSizeOf);
     }
 }
 void
 gfxFont::AddSizeOfIncludingThis(MallocSizeOf aMallocSizeOf,
                                 FontCacheSizes* aSizes) const
 {
     aSizes->mFontInstances += aMallocSizeOf(this);
     AddSizeOfExcludingThis(aMallocSizeOf, aSizes);
 }
 void
 gfxFont::AddGlyphChangeObserver(GlyphChangeObserver *aObserver)
 {
     if (!mGlyphChangeObservers) {
         mGlyphChangeObservers = new nsTHashtable<nsPtrHashKey<GlyphChangeObserver> >;
     }
     mGlyphChangeObservers->PutEntry(aObserver);
 }
 void
 gfxFont::RemoveGlyphChangeObserver(GlyphChangeObserver *aObserver)
 {
     NS_ASSERTION(mGlyphChangeObservers, "No observers registered");
     NS_ASSERTION(mGlyphChangeObservers->Contains(aObserver), "Observer not registered");
     mGlyphChangeObservers->RemoveEntry(aObserver);
 }
 gfxGlyphExtents::~gfxGlyphExtents()
 {
 #ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
     gGlyphExtentsWidthsTotalSize +=
         mContainedGlyphWidths.SizeOfExcludingThis(&FontCacheMallocSizeOf);
     gGlyphExtentsCount++;
 #endif
     MOZ_COUNT_DTOR(gfxGlyphExtents);
 }
 bool
 gfxGlyphExtents::GetTightGlyphExtentsAppUnits(gfxFont *aFont,
     gfxContext *aContext, uint32_t aGlyphID, gfxRect *aExtents)
 {
     HashEntry *entry = mTightGlyphExtents.GetEntry(aGlyphID);
     if (!entry) {
         if (!aContext) {
             NS_WARNING("Could not get glyph extents (no aContext)");
             return false;
         }
         if (aFont->SetupCairoFont(aContext)) {
 #ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
             ++gGlyphExtentsSetupLazyTight;
 #endif
             aFont->SetupGlyphExtents(aContext, aGlyphID, true, this);
             entry = mTightGlyphExtents.GetEntry(aGlyphID);
         }
         if (!entry) {
             NS_WARNING("Could not get glyph extents");
             return false;
         }
     }
     *aExtents = gfxRect(entry->x, entry->y, entry->width, entry->height);
     return true;
 }
 gfxGlyphExtents::GlyphWidths::~GlyphWidths()
 {
     uint32_t i, count = mBlocks.Length();
     for (i = 0; i < count; ++i) {
         uintptr_t bits = mBlocks[i];
         if (bits && !(bits & 0x1)) {
             delete[] reinterpret_cast<uint16_t *>(bits);
         }
     }
 }
 uint32_t
 gfxGlyphExtents::GlyphWidths::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
 {
     uint32_t i;
     uint32_t size = mBlocks.SizeOfExcludingThis(aMallocSizeOf);
     for (i = 0; i < mBlocks.Length(); ++i) {
         uintptr_t bits = mBlocks[i];
         if (bits && !(bits & 0x1)) {
             size += aMallocSizeOf(reinterpret_cast<void*>(bits));
         }
     }
     return size;
 }
 void
 gfxGlyphExtents::GlyphWidths::Set(uint32_t aGlyphID, uint16_t aWidth)
 {
     uint32_t block = aGlyphID >> BLOCK_SIZE_BITS;
     uint32_t len = mBlocks.Length();
     if (block >= len) {
         uintptr_t *elems = mBlocks.AppendElements(block + 1 - len);
         if (!elems)
             return;
         memset(elems, 0, sizeof(uintptr_t)*(block + 1 - len));
     }
     uintptr_t bits = mBlocks[block];
     uint32_t glyphOffset = aGlyphID & (BLOCK_SIZE - 1);
     if (!bits) {
         mBlocks[block] = MakeSingle(glyphOffset, aWidth);
         return;
     }
     uint16_t *newBlock;
     if (bits & 0x1) {
         // Expand the block to a real block. We could avoid this by checking
         // glyphOffset == GetGlyphOffset(bits), but that never happens so don't bother
         newBlock = new uint16_t[BLOCK_SIZE];
         if (!newBlock)
             return;
         uint32_t i;
         for (i = 0; i < BLOCK_SIZE; ++i) {
             newBlock[i] = INVALID_WIDTH;
         }
         newBlock[GetGlyphOffset(bits)] = GetWidth(bits);
         mBlocks[block] = reinterpret_cast<uintptr_t>(newBlock);
     } else {
         newBlock = reinterpret_cast<uint16_t *>(bits);
     }
     newBlock[glyphOffset] = aWidth;
 }
 void
 gfxGlyphExtents::SetTightGlyphExtents(uint32_t aGlyphID, const gfxRect& aExtentsAppUnits)
 {
     HashEntry *entry = mTightGlyphExtents.PutEntry(aGlyphID);
     if (!entry)
         return;
     entry->x = aExtentsAppUnits.X();
     entry->y = aExtentsAppUnits.Y();
     entry->width = aExtentsAppUnits.Width();
     entry->height = aExtentsAppUnits.Height();
 }
 size_t
 gfxGlyphExtents::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
 {
     return mContainedGlyphWidths.SizeOfExcludingThis(aMallocSizeOf) +
         mTightGlyphExtents.SizeOfExcludingThis(nullptr, aMallocSizeOf);
 }
 size_t
 gfxGlyphExtents::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const
 {
     return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
 }
 gfxFontGroup::gfxFontGroup(const nsAString& aFamilies,
                            const gfxFontStyle *aStyle,
                            gfxUserFontSet *aUserFontSet)
     : mFamilies(aFamilies)
     , mStyle(*aStyle)
     , mUnderlineOffset(UNDERLINE_OFFSET_NOT_SET)
     , mHyphenWidth(-1)
     , mUserFontSet(aUserFontSet)
     , mTextPerf(nullptr)
     , mPageLang(gfxPlatform::GetFontPrefLangFor(aStyle->language))
     , mSkipDrawing(false)
 {
     // We don't use SetUserFontSet() here, as we want to unconditionally call
     // BuildFontList() rather than only do UpdateFontList() if it changed.
     mCurrGeneration = GetGeneration();
     BuildFontList();
 }
 void
 gfxFontGroup::BuildFontList()
 {
 // "#if" to be removed once all platforms are moved to gfxPlatformFontList interface
 // and subclasses of gfxFontGroup eliminated
 #if defined(XP_MACOSX) || defined(XP_WIN) || defined(ANDROID)
     ForEachFont(FindPlatformFont, this);
     if (mFonts.Length() == 0) {
         bool needsBold;
         gfxPlatformFontList *pfl = gfxPlatformFontList::PlatformFontList();
         gfxFontFamily *defaultFamily = pfl->GetDefaultFont(&mStyle);
         NS_ASSERTION(defaultFamily,
                      "invalid default font returned by GetDefaultFont");
         if (defaultFamily) {
             gfxFontEntry *fe = defaultFamily->FindFontForStyle(mStyle,
                                                                needsBold);
             if (fe) {
                 nsRefPtr<gfxFont> font = fe->FindOrMakeFont(&mStyle,
                                                             needsBold);
                 if (font) {
                     mFonts.AppendElement(FamilyFace(defaultFamily, font));
                 }
             }
         }
         if (mFonts.Length() == 0) {
             // Try for a "font of last resort...."
             // Because an empty font list would be Really Bad for later code
             // that assumes it will be able to get valid metrics for layout,
             // just look for the first usable font and put in the list.
             // (see bug 554544)
             nsAutoTArray<nsRefPtr<gfxFontFamily>,200> families;
             pfl->GetFontFamilyList(families);
             uint32_t count = families.Length();
             for (uint32_t i = 0; i < count; ++i) {
                 gfxFontEntry *fe = families[i]->FindFontForStyle(mStyle,
                                                                  needsBold);
                 if (fe) {
                     nsRefPtr<gfxFont> font = fe->FindOrMakeFont(&mStyle,
                                                                 needsBold);
                     if (font) {
                         mFonts.AppendElement(FamilyFace(families[i], font));
                         break;
                     }
                 }
             }
         }
         if (mFonts.Length() == 0) {
             // an empty font list at this point is fatal; we're not going to
             // be able to do even the most basic layout operations
             char msg[256]; // CHECK buffer length if revising message below
             sprintf(msg, "unable to find a usable font (%.220s)",
                     NS_ConvertUTF16toUTF8(mFamilies).get());
             NS_RUNTIMEABORT(msg);
         }
     }
     if (!mStyle.systemFont) {
         uint32_t count = mFonts.Length();
         for (uint32_t i = 0; i < count; ++i) {
             gfxFont* font = mFonts[i].Font();
             if (font->GetFontEntry()->mIsBadUnderlineFont) {
                 gfxFloat first = mFonts[0].Font()->GetMetrics().underlineOffset;
                 gfxFloat bad = font->GetMetrics().underlineOffset;
                 mUnderlineOffset = std::min(first, bad);
                 break;
             }
         }
     }
 #endif
 }
 bool
 gfxFontGroup::FindPlatformFont(const nsAString& aName,
                                const nsACString& aGenericName,
                                bool aUseFontSet,
                                void *aClosure)
 {
     gfxFontGroup *fontGroup = static_cast<gfxFontGroup*>(aClosure);
     const gfxFontStyle *fontStyle = fontGroup->GetStyle();
     bool needsBold;
     gfxFontFamily *family = nullptr;
     gfxFontEntry *fe = nullptr;
     if (aUseFontSet) {
         // First, look up in the user font set...
         // If the fontSet matches the family, we must not look for a platform
         // font of the same name, even if we fail to actually get a fontEntry
         // here; we'll fall back to the next name in the CSS font-family list.
         gfxUserFontSet *fs = fontGroup->GetUserFontSet();
         if (fs) {
             // If the fontSet matches the family, but the font has not yet finished
             // loading (nor has its load timeout fired), the fontGroup should wait
             // for the download, and not actually draw its text yet.
             family = fs->GetFamily(aName);
             if (family) {
                 bool waitForUserFont = false;
                 fe = fs->FindFontEntry(family, *fontStyle,
                                        needsBold, waitForUserFont);
                 if (!fe && waitForUserFont) {
                     fontGroup->mSkipDrawing = true;
                 }
             }
         }
     }
     // Not known in the user font set ==> check system fonts
     // XXX: Fallback is bad..
     if (!family) {
         gfxPlatformFontList *fontList = gfxPlatformFontList::PlatformFontList();
         family = fontList->FindFamily(aName);
         if (family) {
             fe = family->FindFontForStyle(*fontStyle, needsBold);
         }
     }
     // add to the font group, unless it's already there
     if (fe && !fontGroup->HasFont(fe)) {
         nsRefPtr<gfxFont> font = fe->FindOrMakeFont(fontStyle, needsBold);
         if (font) {
             fontGroup->mFonts.AppendElement(FamilyFace(family, font));
         }
     }
     return true;
 }
 bool
 gfxFontGroup::HasFont(const gfxFontEntry *aFontEntry)
 {
     uint32_t count = mFonts.Length();
     for (uint32_t i = 0; i < count; ++i) {
         if (mFonts[i].Font()->GetFontEntry() == aFontEntry)
             return true;
     }
     return false;
 }
 gfxFontGroup::~gfxFontGroup()
 {
     mFonts.Clear();
 }
 gfxFontGroup *
 gfxFontGroup::Copy(const gfxFontStyle *aStyle)
 {
     gfxFontGroup *fg = new gfxFontGroup(mFamilies, aStyle, mUserFontSet);
     fg->SetTextPerfMetrics(mTextPerf);
     return fg;
 }
 bool
 gfxFontGroup::IsInvalidChar(uint8_t ch)
 {
     return ((ch & 0x7f) < 0x20 || ch == 0x7f);
 }
 bool
 gfxFontGroup::IsInvalidChar(char16_t ch)
 {
     // All printable 7-bit ASCII values are OK
     if (ch >= ' ' && ch < 0x7f) {
         return false;
     }
     // No point in sending non-printing control chars through font shaping
     if (ch <= 0x9f) {
         return true;
     }
     return (((ch & 0xFF00) == 0x2000 /* Unicode control character */ &&
              (ch == 0x200B/*ZWSP*/ || ch == 0x2028/*LSEP*/ || ch == 0x2029/*PSEP*/)) ||
             IsBidiControl(ch));
 }
 bool
 gfxFontGroup::ForEachFont(FontCreationCallback fc,
                           void *closure)
 {
     return ForEachFontInternal(mFamilies, mStyle.language,
                                true, true, true, fc, closure);
 }
 bool
 gfxFontGroup::ForEachFont(const nsAString& aFamilies,
                           nsIAtom *aLanguage,
                           FontCreationCallback fc,
                           void *closure)
 {
     return ForEachFontInternal(aFamilies, aLanguage,
                                false, true, true, fc, closure);
 }
 struct ResolveData {
     ResolveData(gfxFontGroup::FontCreationCallback aCallback,
                 nsACString& aGenericFamily,
                 bool aUseFontSet,
                 void *aClosure) :
         mCallback(aCallback),
         mGenericFamily(aGenericFamily),
         mUseFontSet(aUseFontSet),
         mClosure(aClosure) {
     }
     gfxFontGroup::FontCreationCallback mCallback;
     nsCString mGenericFamily;
     bool mUseFontSet;
     void *mClosure;
 };
 bool
 gfxFontGroup::ForEachFontInternal(const nsAString& aFamilies,
                                   nsIAtom *aLanguage,
                                   bool aResolveGeneric,
                                   bool aResolveFontName,
                                   bool aUseFontSet,
                                   FontCreationCallback fc,
                                   void *closure)
 {
     const char16_t kSingleQuote  = char16_t('\'');
     const char16_t kDoubleQuote  = char16_t('\"');
     const char16_t kComma        = char16_t(',');
     nsIAtom *groupAtom = nullptr;
     nsAutoCString groupString;
     if (aLanguage) {
         if (!gLangService) {
             CallGetService(NS_LANGUAGEATOMSERVICE_CONTRACTID, &gLangService);
         }
         if (gLangService) {
             nsresult rv;
             groupAtom = gLangService->GetLanguageGroup(aLanguage, &rv);
         }
     }
     if (!groupAtom) {
         groupAtom = nsGkAtoms::Unicode;
     }
     groupAtom->ToUTF8String(groupString);
     nsPromiseFlatString families(aFamilies);
     const char16_t *p, *p_end;
     families.BeginReading(p);
     families.EndReading(p_end);
     nsAutoString family;
     nsAutoCString lcFamily;
     nsAutoString genericFamily;
     while (p < p_end) {
         while (nsCRT::IsAsciiSpace(*p) || *p == kComma)
             if (++p == p_end)
                 return true;
         bool generic;
         if (*p == kSingleQuote || *p == kDoubleQuote) {
             // quoted font family
             char16_t quoteMark = *p;
             if (++p == p_end)
                 return true;
             const char16_t *nameStart = p;
             // XXX What about CSS character escapes?
             while (*p != quoteMark)
                 if (++p == p_end)
                     return true;
             family = Substring(nameStart, p);
             generic = false;
             genericFamily.SetIsVoid(true);
             while (++p != p_end && *p != kComma)
                 /* nothing */ ;
         } else {
             // unquoted font family
             const char16_t *nameStart = p;
             while (++p != p_end && *p != kComma)
                 /* nothing */ ;
             family = Substring(nameStart, p);
             family.CompressWhitespace(false, true);
             if (aResolveGeneric &&
                 (family.LowerCaseEqualsLiteral("serif") ||
                  family.LowerCaseEqualsLiteral("sans-serif") ||
                  family.LowerCaseEqualsLiteral("monospace") ||
                  family.LowerCaseEqualsLiteral("cursive") ||
                  family.LowerCaseEqualsLiteral("fantasy")))
             {
                 generic = true;
                 ToLowerCase(NS_LossyConvertUTF16toASCII(family), lcFamily);
                 nsAutoCString prefName("font.name.");
                 prefName.Append(lcFamily);
                 prefName.AppendLiteral(".");
                 prefName.Append(groupString);
                 nsAdoptingString value = Preferences::GetString(prefName.get());
                 if (value) {
                     CopyASCIItoUTF16(lcFamily, genericFamily);
                     family = value;
                 }
             } else {
                 generic = false;
                 genericFamily.SetIsVoid(true);
             }
         }
         NS_LossyConvertUTF16toASCII gf(genericFamily);
         if (generic) {
             ForEachFontInternal(family, groupAtom, false,
                                 aResolveFontName, false,
                                 fc, closure);
         } else if (!family.IsEmpty()) {
             if (aResolveFontName) {
                 ResolveData data(fc, gf, aUseFontSet, closure);
                 bool aborted = false, needsBold;
                 nsresult rv = NS_OK;
                 bool foundFamily = false;
                 bool waitForUserFont = false;
                 gfxFontEntry *fe = nullptr;
                 if (aUseFontSet && mUserFontSet) {
                     gfxFontFamily *fam = mUserFontSet->GetFamily(family);
                     if (fam) {
                         fe = mUserFontSet->FindFontEntry(fam, mStyle,
                                                          needsBold,
                                                          waitForUserFont);
                     }
                 }
                 if (fe) {
                     gfxFontGroup::FontResolverProc(family, &data);
                 } else {
                     if (waitForUserFont) {
                         mSkipDrawing = true;
                     }
                     if (!foundFamily) {
                         gfxPlatform *pf = gfxPlatform::GetPlatform();
                         // XXX: Fallback is bad
                         rv = pf->ResolveFontName(family,
                                                  gfxFontGroup::FontResolverProc,
                                                  &data, aborted);
                     }
                 }
                 if (NS_FAILED(rv) || aborted)
                     return false;
             }
             else {
                 if (!fc(family, gf, aUseFontSet, closure))
                     return false;
             }
         }
         if (generic && aResolveGeneric) {
             nsAutoCString prefName("font.name-list.");
             prefName.Append(lcFamily);
             prefName.AppendLiteral(".");
             prefName.Append(groupString);
             nsAdoptingString value = Preferences::GetString(prefName.get());
             if (value) {
                 ForEachFontInternal(value, groupAtom, false,
                                     aResolveFontName, false,
                                     fc, closure);
             }
         }
         ++p; // may advance past p_end
     }
     return true;
 }
 bool
 gfxFontGroup::FontResolverProc(const nsAString& aName, void *aClosure)
 {
     ResolveData *data = reinterpret_cast<ResolveData*>(aClosure);
     return (data->mCallback)(aName, data->mGenericFamily, data->mUseFontSet,
                              data->mClosure);
 }
 gfxTextRun *
 gfxFontGroup::MakeEmptyTextRun(const Parameters *aParams, uint32_t aFlags)
 {
     aFlags |= TEXT_IS_8BIT | TEXT_IS_ASCII | TEXT_IS_PERSISTENT;
     return gfxTextRun::Create(aParams, 0, this, aFlags);
 }
 gfxTextRun *
 gfxFontGroup::MakeSpaceTextRun(const Parameters *aParams, uint32_t aFlags)
 {
     aFlags |= TEXT_IS_8BIT | TEXT_IS_ASCII | TEXT_IS_PERSISTENT;
     gfxTextRun *textRun = gfxTextRun::Create(aParams, 1, this, aFlags);
     if (!textRun) {
         return nullptr;
     }
     gfxFont *font = GetFontAt(0);
     if (MOZ_UNLIKELY(GetStyle()->size == 0)) {
         // Short-circuit for size-0 fonts, as Windows and ATSUI can't handle
         // them, and always create at least size 1 fonts, i.e. they still
         // render something for size 0 fonts.
         textRun->AddGlyphRun(font, gfxTextRange::kFontGroup, 0, false);
     }
     else {
         if (font->GetSpaceGlyph()) {
             // Normally, the font has a cached space glyph, so we can avoid
             // the cost of calling FindFontForChar.
             textRun->SetSpaceGlyph(font, aParams->mContext, 0);
         } else {
             // In case the primary font doesn't have <space> (bug 970891),
             // find one that does.
             uint8_t matchType;
             nsRefPtr<gfxFont> spaceFont =
                 FindFontForChar(' ', 0, MOZ_SCRIPT_LATIN, nullptr, &matchType);
             if (spaceFont) {
                 textRun->SetSpaceGlyph(spaceFont, aParams->mContext, 0);
             }
         }
     }
     // Note that the gfxGlyphExtents glyph bounds storage for the font will
     // always contain an entry for the font's space glyph, so we don't have
     // to call FetchGlyphExtents here.
     return textRun;
 }
 gfxTextRun *
 gfxFontGroup::MakeBlankTextRun(uint32_t aLength,
                                const Parameters *aParams, uint32_t aFlags)
 {
     gfxTextRun *textRun =
         gfxTextRun::Create(aParams, aLength, this, aFlags);
     if (!textRun) {
         return nullptr;
     }
     textRun->AddGlyphRun(GetFontAt(0), gfxTextRange::kFontGroup, 0, false);
     return textRun;
 }
 gfxTextRun *
 gfxFontGroup::MakeHyphenTextRun(gfxContext *aCtx, uint32_t aAppUnitsPerDevUnit)
 {
     // only use U+2010 if it is supported by the first font in the group;
     // it's better to use ASCII '-' from the primary font than to fall back to
     // U+2010 from some other, possibly poorly-matching face
     static const char16_t hyphen = 0x2010;
     gfxFont *font = GetFontAt(0);
     if (font && font->HasCharacter(hyphen)) {
         return MakeTextRun(&hyphen, 1, aCtx, aAppUnitsPerDevUnit,
                            gfxFontGroup::TEXT_IS_PERSISTENT);
     }
     static const uint8_t dash = '-';
     return MakeTextRun(&dash, 1, aCtx, aAppUnitsPerDevUnit,
                        gfxFontGroup::TEXT_IS_PERSISTENT);
 }
 gfxFloat
 gfxFontGroup::GetHyphenWidth(gfxTextRun::PropertyProvider *aProvider)
 {
     if (mHyphenWidth < 0) {
         nsRefPtr<gfxContext> ctx(aProvider->GetContext());
         if (ctx) {
             nsAutoPtr<gfxTextRun>
                 hyphRun(MakeHyphenTextRun(ctx,
                                           aProvider->GetAppUnitsPerDevUnit()));
             mHyphenWidth = hyphRun.get() ?
                 hyphRun->GetAdvanceWidth(0, hyphRun->GetLength(), nullptr) : 0;
         }
     }
     return mHyphenWidth;
 }
 gfxTextRun *
 gfxFontGroup::MakeTextRun(const uint8_t *aString, uint32_t aLength,
                           const Parameters *aParams, uint32_t aFlags)
 {
     if (aLength == 0) {
         return MakeEmptyTextRun(aParams, aFlags);
     }
     if (aLength == 1 && aString[0] == ' ') {
         return MakeSpaceTextRun(aParams, aFlags);
     }
     aFlags |= TEXT_IS_8BIT;
     if (GetStyle()->size == 0) {
         // Short-circuit for size-0 fonts, as Windows and ATSUI can't handle
         // them, and always create at least size 1 fonts, i.e. they still
         // render something for size 0 fonts.
         return MakeBlankTextRun(aLength, aParams, aFlags);
     }
     gfxTextRun *textRun = gfxTextRun::Create(aParams, aLength,
                                              this, aFlags);
     if (!textRun) {
         return nullptr;
     }
     InitTextRun(aParams->mContext, textRun, aString, aLength);
     textRun->FetchGlyphExtents(aParams->mContext);
     return textRun;
 }
 gfxTextRun *
 gfxFontGroup::MakeTextRun(const char16_t *aString, uint32_t aLength,
                           const Parameters *aParams, uint32_t aFlags)
 {
     if (aLength == 0) {
         return MakeEmptyTextRun(aParams, aFlags);
     }
     if (aLength == 1 && aString[0] == ' ') {
         return MakeSpaceTextRun(aParams, aFlags);
     }
     if (GetStyle()->size == 0) {
         return MakeBlankTextRun(aLength, aParams, aFlags);
     }
     gfxTextRun *textRun = gfxTextRun::Create(aParams, aLength,
                                              this, aFlags);
     if (!textRun) {
         return nullptr;
     }
     InitTextRun(aParams->mContext, textRun, aString, aLength);
     textRun->FetchGlyphExtents(aParams->mContext);
     return textRun;
 }
 template<typename T>
 void
 gfxFontGroup::InitTextRun(gfxContext *aContext,
                           gfxTextRun *aTextRun,
                           const T *aString,
                           uint32_t aLength)
 {
     NS_ASSERTION(aLength > 0, "don't call InitTextRun for a zero-length run");
     // we need to do numeral processing even on 8-bit text,
     // in case we're converting Western to Hindi/Arabic digits
     int32_t numOption = gfxPlatform::GetPlatform()->GetBidiNumeralOption();
     nsAutoArrayPtr<char16_t> transformedString;
     if (numOption != IBMBIDI_NUMERAL_NOMINAL) {
         // scan the string for numerals that may need to be transformed;
         // if we find any, we'll make a local copy here and use that for
         // font matching and glyph generation/shaping
         bool prevIsArabic =
             (aTextRun->GetFlags() & gfxTextRunFactory::TEXT_INCOMING_ARABICCHAR) != 0;
         for (uint32_t i = 0; i < aLength; ++i) {
             char16_t origCh = aString[i];
             char16_t newCh = HandleNumberInChar(origCh, prevIsArabic, numOption);
             if (newCh != origCh) {
                 if (!transformedString) {
                     transformedString = new char16_t[aLength];
                     if (sizeof(T) == sizeof(char16_t)) {
                         memcpy(transformedString.get(), aString, i * sizeof(char16_t));
                     } else {
                         for (uint32_t j = 0; j < i; ++j) {
                             transformedString[j] = aString[j];
                         }
                     }
                 }
             }
             if (transformedString) {
                 transformedString[i] = newCh;
             }
             prevIsArabic = IS_ARABIC_CHAR(newCh);
         }
     }
 #ifdef PR_LOGGING
     PRLogModuleInfo *log = (mStyle.systemFont ?
                             gfxPlatform::GetLog(eGfxLog_textrunui) :
                             gfxPlatform::GetLog(eGfxLog_textrun));
 #endif
     if (sizeof(T) == sizeof(uint8_t) && !transformedString) {
 #ifdef PR_LOGGING
         if (MOZ_UNLIKELY(PR_LOG_TEST(log, PR_LOG_WARNING))) {
             nsAutoCString lang;
             mStyle.language->ToUTF8String(lang);
             nsAutoCString str((const char*)aString, aLength);
             PR_LOG(log, PR_LOG_WARNING,\
                    ("(%s) fontgroup: [%s] lang: %s script: %d len %d "
                     "weight: %d width: %d style: %s size: %6.2f %d-byte "
                     "TEXTRUN [%s] ENDTEXTRUN\n",
                     (mStyle.systemFont ? "textrunui" : "textrun"),
                     NS_ConvertUTF16toUTF8(mFamilies).get(),
                     lang.get(), MOZ_SCRIPT_LATIN, aLength,
                     uint32_t(mStyle.weight), uint32_t(mStyle.stretch),
                     (mStyle.style & NS_FONT_STYLE_ITALIC ? "italic" :
                     (mStyle.style & NS_FONT_STYLE_OBLIQUE ? "oblique" :
                                                             "normal")),
                     mStyle.size,
                     sizeof(T),
                     str.get()));
         }
 #endif
         // the text is still purely 8-bit; bypass the script-run itemizer
         // and treat it as a single Latin run
         InitScriptRun(aContext, aTextRun, aString,
 , aLength, MOZ_SCRIPT_LATIN);
     } else {
         const char16_t *textPtr;
         if (transformedString) {
             textPtr = transformedString.get();
         } else {
             // typecast to avoid compilation error for the 8-bit version,
             // even though this is dead code in that case
             textPtr = reinterpret_cast<const char16_t*>(aString);
         }
         // split into script runs so that script can potentially influence
         // the font matching process below
         gfxScriptItemizer scriptRuns(textPtr, aLength);
         uint32_t runStart = 0, runLimit = aLength;
         int32_t runScript = MOZ_SCRIPT_LATIN;
         while (scriptRuns.Next(runStart, runLimit, runScript)) {
 #ifdef PR_LOGGING
             if (MOZ_UNLIKELY(PR_LOG_TEST(log, PR_LOG_WARNING))) {
                 nsAutoCString lang;
                 mStyle.language->ToUTF8String(lang);
                 uint32_t runLen = runLimit - runStart;
                 PR_LOG(log, PR_LOG_WARNING,\
                        ("(%s) fontgroup: [%s] lang: %s script: %d len %d "
                         "weight: %d width: %d style: %s size: %6.2f %d-byte "
                         "TEXTRUN [%s] ENDTEXTRUN\n",
                         (mStyle.systemFont ? "textrunui" : "textrun"),
                         NS_ConvertUTF16toUTF8(mFamilies).get(),
                         lang.get(), runScript, runLen,
                         uint32_t(mStyle.weight), uint32_t(mStyle.stretch),
                         (mStyle.style & NS_FONT_STYLE_ITALIC ? "italic" :
                         (mStyle.style & NS_FONT_STYLE_OBLIQUE ? "oblique" :
                                                                 "normal")),
                         mStyle.size,
                         sizeof(T),
                         NS_ConvertUTF16toUTF8(textPtr + runStart, runLen).get()));
             }
 #endif
             InitScriptRun(aContext, aTextRun, textPtr,
                           runStart, runLimit, runScript);
         }
     }
     if (sizeof(T) == sizeof(char16_t) && aLength > 0) {
         gfxTextRun::CompressedGlyph *glyph = aTextRun->GetCharacterGlyphs();
         if (!glyph->IsSimpleGlyph()) {
             glyph->SetClusterStart(true);
         }
     }
     // It's possible for CoreText to omit glyph runs if it decides they contain
     // only invisibles (e.g., U+FEFF, see reftest 474417-1). In this case, we
     // need to eliminate them from the glyph run array to avoid drawing "partial
     // ligatures" with the wrong font.
     // We don't do this during InitScriptRun (or gfxFont::InitTextRun) because
     // it will iterate back over all glyphruns in the textrun, which leads to
     // pathologically-bad perf in the case where a textrun contains many script
     // changes (see bug 680402) - we'd end up re-sanitizing all the earlier runs
     // every time a new script subrun is processed.
     aTextRun->SanitizeGlyphRuns();
     aTextRun->SortGlyphRuns();
 }
 template<typename T>
 void
 gfxFontGroup::InitScriptRun(gfxContext *aContext,
                             gfxTextRun *aTextRun,
                             const T *aString,
                             uint32_t aScriptRunStart,
                             uint32_t aScriptRunEnd,
                             int32_t aRunScript)
 {
     NS_ASSERTION(aScriptRunEnd > aScriptRunStart,
                  "don't call InitScriptRun for a zero-length run");
     gfxFont *mainFont = GetFontAt(0);
     uint32_t runStart = aScriptRunStart;
     nsAutoTArray<gfxTextRange,3> fontRanges;
     ComputeRanges(fontRanges, aString + aScriptRunStart,
                   aScriptRunEnd - aScriptRunStart, aRunScript);
     uint32_t numRanges = fontRanges.Length();
     for (uint32_t r = 0; r < numRanges; r++) {
         const gfxTextRange& range = fontRanges[r];
         uint32_t matchedLength = range.Length();
         gfxFont *matchedFont = range.font;
         // create the glyph run for this range
         if (matchedFont) {
             aTextRun->AddGlyphRun(matchedFont, range.matchType,
                                   runStart, (matchedLength > 0));
             // do glyph layout and record the resulting positioned glyphs
             if (!matchedFont->SplitAndInitTextRun(aContext, aTextRun, aString,
                                                   runStart, matchedLength,
                                                   aRunScript)) {
                 // glyph layout failed! treat as missing glyphs
                 matchedFont = nullptr;
             }
         } else {
             aTextRun->AddGlyphRun(mainFont, gfxTextRange::kFontGroup,
                                   runStart, (matchedLength > 0));
         }
         if (!matchedFont) {
             // We need to set cluster boundaries (and mark spaces) so that
             // surrogate pairs, combining characters, etc behave properly,
             // even if we don't have glyphs for them
             aTextRun->SetupClusterBoundaries(runStart, aString + runStart,
                                              matchedLength);
             // various "missing" characters may need special handling,
             // so we check for them here
             uint32_t runLimit = runStart + matchedLength;
             for (uint32_t index = runStart; index < runLimit; index++) {
                 T ch = aString[index];
                 // tab and newline are not to be displayed as hexboxes,
                 // but do need to be recorded in the textrun
                 if (ch == '\n') {
                     aTextRun->SetIsNewline(index);
                     continue;
                 }
                 if (ch == '\t') {
                     aTextRun->SetIsTab(index);
                     continue;
                 }
                 // for 16-bit textruns only, check for surrogate pairs and
                 // special Unicode spaces; omit these checks in 8-bit runs
                 if (sizeof(T) == sizeof(char16_t)) {
                     if (NS_IS_HIGH_SURROGATE(ch) &&
                         index + 1 < aScriptRunEnd &&
                         NS_IS_LOW_SURROGATE(aString[index + 1]))
                     {
                         aTextRun->SetMissingGlyph(index,
                                                   SURROGATE_TO_UCS4(ch,
                                                                     aString[index + 1]),
                                                   mainFont);
                         index++;
                         continue;
                     }
                     // check if this is a known Unicode whitespace character that
                     // we can render using the space glyph with a custom width
                     gfxFloat wid = mainFont->SynthesizeSpaceWidth(ch);
                     if (wid >= 0.0) {
                         nscoord advance =
                             aTextRun->GetAppUnitsPerDevUnit() * floor(wid + 0.5);
                         if (gfxShapedText::CompressedGlyph::IsSimpleAdvance(advance)) {
                             aTextRun->GetCharacterGlyphs()[index].
                                 SetSimpleGlyph(advance,
                                                mainFont->GetSpaceGlyph());
                         } else {
                             gfxTextRun::DetailedGlyph detailedGlyph;
                             detailedGlyph.mGlyphID = mainFont->GetSpaceGlyph();
                             detailedGlyph.mAdvance = advance;
                             detailedGlyph.mXOffset = detailedGlyph.mYOffset = 0;
                             gfxShapedText::CompressedGlyph g;
                             g.SetComplex(true, true, 1);
                             aTextRun->SetGlyphs(index,
                                                 g, &detailedGlyph);
                         }
                         continue;
                     }
                 }
                 if (IsInvalidChar(ch)) {
                     // invalid chars are left as zero-width/invisible
                     continue;
                 }
                 // record char code so we can draw a box with the Unicode value
                 aTextRun->SetMissingGlyph(index, ch, mainFont);
             }
         }
         runStart += matchedLength;
     }
 }
 gfxTextRun *
 gfxFontGroup::GetEllipsisTextRun(int32_t aAppUnitsPerDevPixel,
                                  LazyReferenceContextGetter& aRefContextGetter)
 {
     if (mCachedEllipsisTextRun &&
         mCachedEllipsisTextRun->GetAppUnitsPerDevUnit() == aAppUnitsPerDevPixel) {
         return mCachedEllipsisTextRun;
     }
     // Use a Unicode ellipsis if the font supports it,
     // otherwise use three ASCII periods as fallback.
     gfxFont* firstFont = GetFontAt(0);
     nsString ellipsis = firstFont->HasCharacter(kEllipsisChar[0])
         ? nsDependentString(kEllipsisChar,
                             ArrayLength(kEllipsisChar) - 1)
         : nsDependentString(kASCIIPeriodsChar,
                             ArrayLength(kASCIIPeriodsChar) - 1);
     nsRefPtr<gfxContext> refCtx = aRefContextGetter.GetRefContext();
     Parameters params = {
         refCtx, nullptr, nullptr, nullptr, 0, aAppUnitsPerDevPixel
     };
     gfxTextRun* textRun =
         MakeTextRun(ellipsis.get(), ellipsis.Length(), &params, TEXT_IS_PERSISTENT);
     if (!textRun) {
         return nullptr;
     }
     mCachedEllipsisTextRun = textRun;
     textRun->ReleaseFontGroup(); // don't let the presence of a cached ellipsis
                                  // textrun prolong the fontgroup's life
     return textRun;
 }
 already_AddRefed<gfxFont>
 gfxFontGroup::TryAllFamilyMembers(gfxFontFamily* aFamily, uint32_t aCh)
 {
     if (!aFamily->TestCharacterMap(aCh)) {
         return nullptr;
     }
     // Note that we don't need the actual runScript in matchData for
     // gfxFontFamily::SearchAllFontsForChar, it's only used for the
     // system-fallback case. So we can just set it to 0 here.
     GlobalFontMatch matchData(aCh, 0, &mStyle);
     aFamily->SearchAllFontsForChar(&matchData);
     gfxFontEntry *fe = matchData.mBestMatch;
     if (!fe) {
         return nullptr;
     }
     bool needsBold = mStyle.weight >= 600 && !fe->IsBold();
     nsRefPtr<gfxFont> font = fe->FindOrMakeFont(&mStyle, needsBold);
     return font.forget();
 }
 already_AddRefed<gfxFont>
 gfxFontGroup::FindFontForChar(uint32_t aCh, uint32_t aPrevCh,
                               int32_t aRunScript, gfxFont *aPrevMatchedFont,
                               uint8_t *aMatchType)
 {
     // To optimize common cases, try the first font in the font-group
     // before going into the more detailed checks below
     uint32_t nextIndex = 0;
     bool isJoinControl = gfxFontUtils::IsJoinControl(aCh);
     bool wasJoinCauser = gfxFontUtils::IsJoinCauser(aPrevCh);
     bool isVarSelector = gfxFontUtils::IsVarSelector(aCh);
     if (!isJoinControl && !wasJoinCauser && !isVarSelector) {
         nsRefPtr<gfxFont> firstFont = mFonts[0].Font();
         if (firstFont->HasCharacter(aCh)) {
             *aMatchType = gfxTextRange::kFontGroup;
             return firstFont.forget();
         }
         // It's possible that another font in the family (e.g. regular face,
         // where the requested style was italic) will support the character
         nsRefPtr<gfxFont> font = TryAllFamilyMembers(mFonts[0].Family(), aCh);
         if (font) {
             *aMatchType = gfxTextRange::kFontGroup;
             return font.forget();
         }
         // we don't need to check the first font again below
         ++nextIndex;
     }
     if (aPrevMatchedFont) {
         // Don't switch fonts for control characters, regardless of
         // whether they are present in the current font, as they won't
         // actually be rendered (see bug 716229)
         if (isJoinControl ||
             GetGeneralCategory(aCh) == HB_UNICODE_GENERAL_CATEGORY_CONTROL) {
             nsRefPtr<gfxFont> ret = aPrevMatchedFont;
             return ret.forget();
         }
         // if previous character was a join-causer (ZWJ),
         // use the same font as the previous range if we can
         if (wasJoinCauser) {
             if (aPrevMatchedFont->HasCharacter(aCh)) {
                 nsRefPtr<gfxFont> ret = aPrevMatchedFont;
                 return ret.forget();
             }
         }
     }
     // if this character is a variation selector,
     // use the previous font regardless of whether it supports VS or not.
     // otherwise the text run will be divided.
     if (isVarSelector) {
         if (aPrevMatchedFont) {
             nsRefPtr<gfxFont> ret = aPrevMatchedFont;
             return ret.forget();
         }
         // VS alone. it's meaningless to search different fonts
         return nullptr;
     }
     // 1. check remaining fonts in the font group
     uint32_t fontListLength = FontListLength();
     for (uint32_t i = nextIndex; i < fontListLength; i++) {
         nsRefPtr<gfxFont> font = mFonts[i].Font();
         if (font->HasCharacter(aCh)) {
             *aMatchType = gfxTextRange::kFontGroup;
             return font.forget();
         }
         font = TryAllFamilyMembers(mFonts[i].Family(), aCh);
         if (font) {
             *aMatchType = gfxTextRange::kFontGroup;
             return font.forget();
         }
     }
     // if character is in Private Use Area, don't do matching against pref or system fonts
     if ((aCh >= 0xE000  && aCh <= 0xF8FF) || (aCh >= 0xF0000 && aCh <= 0x10FFFD))
         return nullptr;
     // 2. search pref fonts
     nsRefPtr<gfxFont> font = WhichPrefFontSupportsChar(aCh);
     if (font) {
         *aMatchType = gfxTextRange::kPrefsFallback;
         return font.forget();
     }
     // 3. use fallback fonts
     // -- before searching for something else check the font used for the previous character
     if (aPrevMatchedFont && aPrevMatchedFont->HasCharacter(aCh)) {
         *aMatchType = gfxTextRange::kSystemFallback;
         nsRefPtr<gfxFont> ret = aPrevMatchedFont;
         return ret.forget();
     }
     // never fall back for characters from unknown scripts
     if (aRunScript == HB_SCRIPT_UNKNOWN) {
         return nullptr;
     }
     // for known "space" characters, don't do a full system-fallback search;
     // we'll synthesize appropriate-width spaces instead of missing-glyph boxes
     if (GetGeneralCategory(aCh) ==
             HB_UNICODE_GENERAL_CATEGORY_SPACE_SEPARATOR &&
         GetFontAt(0)->SynthesizeSpaceWidth(aCh) >= 0.0)
     {
         return nullptr;
     }
     // -- otherwise look for other stuff
     *aMatchType = gfxTextRange::kSystemFallback;
     font = WhichSystemFontSupportsChar(aCh, aRunScript);
     return font.forget();
 }
 template<typename T>
 void gfxFontGroup::ComputeRanges(nsTArray<gfxTextRange>& aRanges,
                                  const T *aString, uint32_t aLength,
                                  int32_t aRunScript)
 {
     NS_ASSERTION(aRanges.Length() == 0, "aRanges must be initially empty");
     NS_ASSERTION(aLength > 0, "don't call ComputeRanges for zero-length text");
     uint32_t prevCh = 0;
     int32_t lastRangeIndex = -1;
     // initialize prevFont to the group's primary font, so that this will be
     // used for string-initial control chars, etc rather than risk hitting font
     // fallback for these (bug 716229)
     gfxFont *prevFont = GetFontAt(0);
     // if we use the initial value of prevFont, we treat this as a match from
     // the font group; fixes bug 978313
     uint8_t matchType = gfxTextRange::kFontGroup;
     for (uint32_t i = 0; i < aLength; i++) {
         const uint32_t origI = i; // save off in case we increase for surrogate
         // set up current ch
         uint32_t ch = aString[i];
         // in 16-bit case only, check for surrogate pair
         if (sizeof(T) == sizeof(char16_t)) {
             if ((i + 1 < aLength) && NS_IS_HIGH_SURROGATE(ch) &&
                                  NS_IS_LOW_SURROGATE(aString[i + 1])) {
                 i++;
                 ch = SURROGATE_TO_UCS4(ch, aString[i]);
             }
         }
         if (ch == 0xa0) {
             ch = ' ';
         }
         // find the font for this char
         nsRefPtr<gfxFont> font =
             FindFontForChar(ch, prevCh, aRunScript, prevFont, &matchType);
 #ifndef RELEASE_BUILD
         if (MOZ_UNLIKELY(mTextPerf)) {
             if (matchType == gfxTextRange::kPrefsFallback) {
                 mTextPerf->current.fallbackPrefs++;
             } else if (matchType == gfxTextRange::kSystemFallback) {
                 mTextPerf->current.fallbackSystem++;
             }
         }
 #endif
         prevCh = ch;
         if (lastRangeIndex == -1) {
             // first char ==> make a new range
             aRanges.AppendElement(gfxTextRange(0, 1, font, matchType));
             lastRangeIndex++;
             prevFont = font;
         } else {
             // if font has changed, make a new range
             gfxTextRange& prevRange = aRanges[lastRangeIndex];
             if (prevRange.font != font || prevRange.matchType != matchType) {
                 // close out the previous range
                 prevRange.end = origI;
                 aRanges.AppendElement(gfxTextRange(origI, i + 1,
                                                    font, matchType));
                 lastRangeIndex++;
                 // update prevFont for the next match, *unless* we switched
                 // fonts on a ZWJ, in which case propagating the changed font
                 // is probably not a good idea (see bug 619511)
                 if (sizeof(T) == sizeof(uint8_t) ||
                     !gfxFontUtils::IsJoinCauser(ch))
                 {
                     prevFont = font;
                 }
             }
         }
     }
     aRanges[lastRangeIndex].end = aLength;
 }
 gfxUserFontSet*
 gfxFontGroup::GetUserFontSet()
 {
     return mUserFontSet;
 }
 void
 gfxFontGroup::SetUserFontSet(gfxUserFontSet *aUserFontSet)
 {
     if (aUserFontSet == mUserFontSet) {
         return;
     }
     mUserFontSet = aUserFontSet;
     mCurrGeneration = GetGeneration() - 1;
     UpdateFontList();
 }
 uint64_t
 gfxFontGroup::GetGeneration()
 {
     if (!mUserFontSet)
         return 0;
     return mUserFontSet->GetGeneration();
 }
 void
 gfxFontGroup::UpdateFontList()
 {
     if (mCurrGeneration != GetGeneration()) {
         // xxx - can probably improve this to detect when all fonts were found, so no need to update list
         mFonts.Clear();
         mUnderlineOffset = UNDERLINE_OFFSET_NOT_SET;
         mSkipDrawing = false;
         // bug 548184 - need to clean up FT2, OS/2 platform code to use BuildFontList
 #if defined(XP_MACOSX) || defined(XP_WIN) || defined(ANDROID)
         BuildFontList();
 #else
         ForEachFont(FindPlatformFont, this);
 #endif
         mCurrGeneration = GetGeneration();
         mCachedEllipsisTextRun = nullptr;
     }
 }
 struct PrefFontCallbackData {
     PrefFontCallbackData(nsTArray<nsRefPtr<gfxFontFamily> >& aFamiliesArray)
         : mPrefFamilies(aFamiliesArray)
     {}
     nsTArray<nsRefPtr<gfxFontFamily> >& mPrefFamilies;
     static bool AddFontFamilyEntry(eFontPrefLang aLang, const nsAString& aName, void *aClosure)
     {
         PrefFontCallbackData *prefFontData = static_cast<PrefFontCallbackData*>(aClosure);
         gfxFontFamily *family = gfxPlatformFontList::PlatformFontList()->FindFamily(aName);
         if (family) {
             prefFontData->mPrefFamilies.AppendElement(family);
         }
         return true;
     }
 };
 already_AddRefed<gfxFont>
 gfxFontGroup::WhichPrefFontSupportsChar(uint32_t aCh)
 {
     nsRefPtr<gfxFont> font;
     // get the pref font list if it hasn't been set up already
     uint32_t unicodeRange = FindCharUnicodeRange(aCh);
     eFontPrefLang charLang = gfxPlatform::GetPlatform()->GetFontPrefLangFor(unicodeRange);
     // if the last pref font was the first family in the pref list, no need to recheck through a list of families
     if (mLastPrefFont && charLang == mLastPrefLang &&
         mLastPrefFirstFont && mLastPrefFont->HasCharacter(aCh)) {
         font = mLastPrefFont;
         return font.forget();
     }
     // based on char lang and page lang, set up list of pref lang fonts to check
     eFontPrefLang prefLangs[kMaxLenPrefLangList];
     uint32_t i, numLangs = 0;
     gfxPlatform::GetPlatform()->GetLangPrefs(prefLangs, numLangs, charLang, mPageLang);
     for (i = 0; i < numLangs; i++) {
         nsAutoTArray<nsRefPtr<gfxFontFamily>, 5> families;
         eFontPrefLang currentLang = prefLangs[i];
         gfxPlatformFontList *fontList = gfxPlatformFontList::PlatformFontList();
         // get the pref families for a single pref lang
         if (!fontList->GetPrefFontFamilyEntries(currentLang, &families)) {
             eFontPrefLang prefLangsToSearch[1] = { currentLang };
             PrefFontCallbackData prefFontData(families);
             gfxPlatform::ForEachPrefFont(prefLangsToSearch, 1, PrefFontCallbackData::AddFontFamilyEntry,
                                            &prefFontData);
             fontList->SetPrefFontFamilyEntries(currentLang, families);
         }
         // find the first pref font that includes the character
         uint32_t  j, numPrefs;
         numPrefs = families.Length();
         for (j = 0; j < numPrefs; j++) {
             // look up the appropriate face
             gfxFontFamily *family = families[j];
             if (!family) continue;
             // if a pref font is used, it's likely to be used again in the same text run.
             // the style doesn't change so the face lookup can be cached rather than calling
             // FindOrMakeFont repeatedly.  speeds up FindFontForChar lookup times for subsequent
             // pref font lookups
             if (family == mLastPrefFamily && mLastPrefFont->HasCharacter(aCh)) {
                 font = mLastPrefFont;
                 return font.forget();
             }
             bool needsBold;
             gfxFontEntry *fe = family->FindFontForStyle(mStyle, needsBold);
             // if ch in cmap, create and return a gfxFont
             if (fe && fe->TestCharacterMap(aCh)) {
                 nsRefPtr<gfxFont> prefFont = fe->FindOrMakeFont(&mStyle, needsBold);
                 if (!prefFont) continue;
                 mLastPrefFamily = family;
                 mLastPrefFont = prefFont;
                 mLastPrefLang = charLang;
                 mLastPrefFirstFont = (i == 0 && j == 0);
                 return prefFont.forget();
             }
         }
     }
     return nullptr;
 }
 already_AddRefed<gfxFont>
 gfxFontGroup::WhichSystemFontSupportsChar(uint32_t aCh, int32_t aRunScript)
 {
     gfxFontEntry *fe =
         gfxPlatformFontList::PlatformFontList()->
             SystemFindFontForChar(aCh, aRunScript, &mStyle);
     if (fe) {
         bool wantBold = mStyle.ComputeWeight() >= 6;
         nsRefPtr<gfxFont> font =
             fe->FindOrMakeFont(&mStyle, wantBold && !fe->IsBold());
         return font.forget();
     }
     return nullptr;
 }
 /*static*/ void
 gfxFontGroup::Shutdown()
 {
     NS_IF_RELEASE(gLangService);
 }
 nsILanguageAtomService* gfxFontGroup::gLangService = nullptr;
 #define DEFAULT_PIXEL_FONT_SIZE 16.0f
 /*static*/ uint32_t
 gfxFontStyle::ParseFontLanguageOverride(const nsString& aLangTag)
 {
   if (!aLangTag.Length() || aLangTag.Length() > 4) {
     return NO_FONT_LANGUAGE_OVERRIDE;
   }
   uint32_t index, result = 0;
   for (index = 0; index < aLangTag.Length(); ++index) {
     char16_t ch = aLangTag[index];
     if (!nsCRT::IsAscii(ch)) { // valid tags are pure ASCII
       return NO_FONT_LANGUAGE_OVERRIDE;
     }
     result = (result << 8) + ch;
   }
   while (index++ < 4) {
     result = (result << 8) + 0x20;
   }
   return result;
 }
 gfxFontStyle::gfxFontStyle() :
     language(nsGkAtoms::x_western),
     size(DEFAULT_PIXEL_FONT_SIZE), sizeAdjust(0.0f),
     languageOverride(NO_FONT_LANGUAGE_OVERRIDE),
     weight(NS_FONT_WEIGHT_NORMAL), stretch(NS_FONT_STRETCH_NORMAL),
     systemFont(true), printerFont(false), useGrayscaleAntialiasing(false),
     style(NS_FONT_STYLE_NORMAL)
 {
 }
 gfxFontStyle::gfxFontStyle(uint8_t aStyle, uint16_t aWeight, int16_t aStretch,
                            gfxFloat aSize, nsIAtom *aLanguage,
                            float aSizeAdjust, bool aSystemFont,
                            bool aPrinterFont,
                            const nsString& aLanguageOverride):
     language(aLanguage),
     size(aSize), sizeAdjust(aSizeAdjust),
     languageOverride(ParseFontLanguageOverride(aLanguageOverride)),
     weight(aWeight), stretch(aStretch),
     systemFont(aSystemFont), printerFont(aPrinterFont),
     useGrayscaleAntialiasing(false), style(aStyle)
 {
     MOZ_ASSERT(!mozilla::IsNaN(size));
     MOZ_ASSERT(!mozilla::IsNaN(sizeAdjust));
     if (weight > 900)
         weight = 900;
     if (weight < 100)
         weight = 100;
     if (size >= FONT_MAX_SIZE) {
         size = FONT_MAX_SIZE;
         sizeAdjust = 0.0;
     } else if (size < 0.0) {
         NS_WARNING("negative font size");
         size = 0.0;
     }
     if (!language) {
         NS_WARNING("null language");
         language = nsGkAtoms::x_western;
     }
 }
 gfxFontStyle::gfxFontStyle(const gfxFontStyle& aStyle) :
     language(aStyle.language),
     featureValueLookup(aStyle.featureValueLookup),
     size(aStyle.size), sizeAdjust(aStyle.sizeAdjust),
     languageOverride(aStyle.languageOverride),
     weight(aStyle.weight), stretch(aStyle.stretch),
     systemFont(aStyle.systemFont), printerFont(aStyle.printerFont),
     useGrayscaleAntialiasing(aStyle.useGrayscaleAntialiasing),
     style(aStyle.style)
 {
     featureSettings.AppendElements(aStyle.featureSettings);
     alternateValues.AppendElements(aStyle.alternateValues);
 }
 int8_t
 gfxFontStyle::ComputeWeight() const
 {
     int8_t baseWeight = (weight + 50) / 100;
     if (baseWeight < 0)
         baseWeight = 0;
     if (baseWeight > 9)
         baseWeight = 9;
     return baseWeight;
 }
 void
 gfxShapedText::SetupClusterBoundaries(uint32_t         aOffset,
                                       const char16_t *aString,
                                       uint32_t         aLength)
 {
     CompressedGlyph *glyphs = GetCharacterGlyphs() + aOffset;
     gfxTextRun::CompressedGlyph extendCluster;
     extendCluster.SetComplex(false, true, 0);
     ClusterIterator iter(aString, aLength);
     // the ClusterIterator won't be able to tell us if the string
     // _begins_ with a cluster-extender, so we handle that here
     if (aLength && IsClusterExtender(*aString)) {
         *glyphs = extendCluster;
     }
     while (!iter.AtEnd()) {
         if (*iter == char16_t(' ')) {
             glyphs->SetIsSpace();
         }
         // advance iter to the next cluster-start (or end of text)
         iter.Next();
         // step past the first char of the cluster
         aString++;
         glyphs++;
         // mark all the rest as cluster-continuations
         while (aString < iter) {
             *glyphs = extendCluster;
             if (NS_IS_LOW_SURROGATE(*aString)) {
                 glyphs->SetIsLowSurrogate();
             }
             glyphs++;
             aString++;
         }
     }
 }
 void
 gfxShapedText::SetupClusterBoundaries(uint32_t       aOffset,
                                       const uint8_t *aString,
                                       uint32_t       aLength)
 {
     CompressedGlyph *glyphs = GetCharacterGlyphs() + aOffset;
     const uint8_t *limit = aString + aLength;
     while (aString < limit) {
         if (*aString == uint8_t(' ')) {
             glyphs->SetIsSpace();
         }
         aString++;
         glyphs++;
     }
 }
 gfxShapedText::DetailedGlyph *
 gfxShapedText::AllocateDetailedGlyphs(uint32_t aIndex, uint32_t aCount)
 {
     NS_ASSERTION(aIndex < GetLength(), "Index out of range");
     if (!mDetailedGlyphs) {
         mDetailedGlyphs = new DetailedGlyphStore();
     }
     DetailedGlyph *details = mDetailedGlyphs->Allocate(aIndex, aCount);
     if (!details) {
         GetCharacterGlyphs()[aIndex].SetMissing(0);
         return nullptr;
     }
     return details;
 }
 void
 gfxShapedText::SetGlyphs(uint32_t aIndex, CompressedGlyph aGlyph,
                          const DetailedGlyph *aGlyphs)
 {
     NS_ASSERTION(!aGlyph.IsSimpleGlyph(), "Simple glyphs not handled here");
     NS_ASSERTION(aIndex > 0 || aGlyph.IsLigatureGroupStart(),
                  "First character can't be a ligature continuation!");
     uint32_t glyphCount = aGlyph.GetGlyphCount();
     if (glyphCount > 0) {
         DetailedGlyph *details = AllocateDetailedGlyphs(aIndex, glyphCount);
         if (!details) {
             return;
         }
         memcpy(details, aGlyphs, sizeof(DetailedGlyph)*glyphCount);
     }
     GetCharacterGlyphs()[aIndex] = aGlyph;
 }
 #define ZWNJ 0x200C
 #define ZWJ  0x200D
 // U+061C ARABIC LETTER MARK is expected to be added to XIDMOD_DEFAULT_IGNORABLE
 // in a future Unicode update. Add it manually for now
 #define ALM  0x061C
 static inline bool
 IsDefaultIgnorable(uint32_t aChar)
 {
     return GetIdentifierModification(aChar) == XIDMOD_DEFAULT_IGNORABLE ||
            aChar == ZWNJ || aChar == ZWJ || aChar == ALM;
 }
 void
 gfxShapedText::SetMissingGlyph(uint32_t aIndex, uint32_t aChar, gfxFont *aFont)
 {
     uint8_t category = GetGeneralCategory(aChar);
     if (category >= HB_UNICODE_GENERAL_CATEGORY_SPACING_MARK &&
         category <= HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK)
     {
         GetCharacterGlyphs()[aIndex].SetComplex(false, true, 0);
     }
     DetailedGlyph *details = AllocateDetailedGlyphs(aIndex, 1);
     if (!details) {
         return;
     }
     details->mGlyphID = aChar;
     if (IsDefaultIgnorable(aChar)) {
         // Setting advance width to zero will prevent drawing the hexbox
         details->mAdvance = 0;
     } else {
         gfxFloat width =
             std::max(aFont->GetMetrics().aveCharWidth,
                      gfxFontMissingGlyphs::GetDesiredMinWidth(aChar,
                          mAppUnitsPerDevUnit));
         details->mAdvance = uint32_t(width * mAppUnitsPerDevUnit);
     }
     details->mXOffset = 0;
     details->mYOffset = 0;
     GetCharacterGlyphs()[aIndex].SetMissing(1);
 }
 bool
 gfxShapedText::FilterIfIgnorable(uint32_t aIndex, uint32_t aCh)
 {
     if (IsDefaultIgnorable(aCh)) {
         DetailedGlyph *details = AllocateDetailedGlyphs(aIndex, 1);
         if (details) {
             details->mGlyphID = aCh;
             details->mAdvance = 0;
             details->mXOffset = 0;
             details->mYOffset = 0;
             GetCharacterGlyphs()[aIndex].SetMissing(1);
             return true;
         }
     }
     return false;
 }
 void
 gfxShapedText::AdjustAdvancesForSyntheticBold(float aSynBoldOffset,
                                               uint32_t aOffset,
                                               uint32_t aLength)
 {
     uint32_t synAppUnitOffset = aSynBoldOffset * mAppUnitsPerDevUnit;
     CompressedGlyph *charGlyphs = GetCharacterGlyphs();
     for (uint32_t i = aOffset; i < aOffset + aLength; ++i) {
          CompressedGlyph *glyphData = charGlyphs + i;
          if (glyphData->IsSimpleGlyph()) {
              // simple glyphs ==> just add the advance
              int32_t advance = glyphData->GetSimpleAdvance() + synAppUnitOffset;
              if (CompressedGlyph::IsSimpleAdvance(advance)) {
                  glyphData->SetSimpleGlyph(advance, glyphData->GetSimpleGlyph());
              } else {
                  // rare case, tested by making this the default
                  uint32_t glyphIndex = glyphData->GetSimpleGlyph();
                  glyphData->SetComplex(true, true, 1);
                  DetailedGlyph detail = {glyphIndex, advance, 0, 0};
                  SetGlyphs(i, *glyphData, &detail);
              }
          } else {
              // complex glyphs ==> add offset at cluster/ligature boundaries
              uint32_t detailedLength = glyphData->GetGlyphCount();
              if (detailedLength) {
                  DetailedGlyph *details = GetDetailedGlyphs(i);
                  if (!details) {
                      continue;
                  }
                  if (IsRightToLeft()) {
                      details[0].mAdvance += synAppUnitOffset;
                  } else {
                      details[detailedLength - 1].mAdvance += synAppUnitOffset;
                  }
              }
          }
     }
 }
 bool
 gfxTextRun::GlyphRunIterator::NextRun()  {
     if (mNextIndex >= mTextRun->mGlyphRuns.Length())
         return false;
     mGlyphRun = &mTextRun->mGlyphRuns[mNextIndex];
     if (mGlyphRun->mCharacterOffset >= mEndOffset)
         return false;
     mStringStart = std::max(mStartOffset, mGlyphRun->mCharacterOffset);
     uint32_t last = mNextIndex + 1 < mTextRun->mGlyphRuns.Length()
         ? mTextRun->mGlyphRuns[mNextIndex + 1].mCharacterOffset : mTextRun->GetLength();
     mStringEnd = std::min(mEndOffset, last);
     ++mNextIndex;
     return true;
 }
 #ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
 static void
 AccountStorageForTextRun(gfxTextRun *aTextRun, int32_t aSign)
 {
     // Ignores detailed glyphs... we don't know when those have been constructed
     // Also ignores gfxSkipChars dynamic storage (which won't be anything
     // for preformatted text)
     // Also ignores GlyphRun array, again because it hasn't been constructed
     // by the time this gets called. If there's only one glyphrun that's stored
     // directly in the textrun anyway so no additional overhead.
     uint32_t length = aTextRun->GetLength();
     int32_t bytes = length * sizeof(gfxTextRun::CompressedGlyph);
     bytes += sizeof(gfxTextRun);
     gTextRunStorage += bytes*aSign;
     gTextRunStorageHighWaterMark = std::max(gTextRunStorageHighWaterMark, gTextRunStorage);
 }
 #endif
 // Helper for textRun creation to preallocate storage for glyph records;
 // this function returns a pointer to the newly-allocated glyph storage.
 // Returns nullptr if allocation fails.
 void *
 gfxTextRun::AllocateStorageForTextRun(size_t aSize, uint32_t aLength)
 {
     // Allocate the storage we need, returning nullptr on failure rather than
     // throwing an exception (because web content can create huge runs).
     void *storage = moz_malloc(aSize + aLength * sizeof(CompressedGlyph));
     if (!storage) {
         NS_WARNING("failed to allocate storage for text run!");
         return nullptr;
     }
     // Initialize the glyph storage (beyond aSize) to zero
     memset(reinterpret_cast<char*>(storage) + aSize, 0,
            aLength * sizeof(CompressedGlyph));
     return storage;
 }
 gfxTextRun *
 gfxTextRun::Create(const gfxTextRunFactory::Parameters *aParams,
                    uint32_t aLength, gfxFontGroup *aFontGroup, uint32_t aFlags)
 {
     void *storage = AllocateStorageForTextRun(sizeof(gfxTextRun), aLength);
     if (!storage) {
         return nullptr;
     }
     return new (storage) gfxTextRun(aParams, aLength, aFontGroup, aFlags);
 }
 gfxTextRun::gfxTextRun(const gfxTextRunFactory::Parameters *aParams,
                        uint32_t aLength, gfxFontGroup *aFontGroup, uint32_t aFlags)
     : gfxShapedText(aLength, aFlags, aParams->mAppUnitsPerDevUnit)
     , mUserData(aParams->mUserData)
     , mFontGroup(aFontGroup)
     , mReleasedFontGroup(false)
 {
     NS_ASSERTION(mAppUnitsPerDevUnit > 0, "Invalid app unit scale");
     MOZ_COUNT_CTOR(gfxTextRun);
     NS_ADDREF(mFontGroup);
 #ifndef RELEASE_BUILD
     gfxTextPerfMetrics *tp = aFontGroup->GetTextPerfMetrics();
     if (tp) {
         tp->current.textrunConst++;
     }
 #endif
     mCharacterGlyphs = reinterpret_cast<CompressedGlyph*>(this + 1);
     if (aParams->mSkipChars) {
         mSkipChars.TakeFrom(aParams->mSkipChars);
     }
 #ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
     AccountStorageForTextRun(this, 1);
 #endif
     mSkipDrawing = mFontGroup->ShouldSkipDrawing();
 }
 gfxTextRun::~gfxTextRun()
 {
 #ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
     AccountStorageForTextRun(this, -1);
 #endif
 #ifdef DEBUG
     // Make it easy to detect a dead text run
     mFlags = 0xFFFFFFFF;
 #endif
     // The cached ellipsis textrun (if any) in a fontgroup will have already
     // been told to release its reference to the group, so we mustn't do that
     // again here.
     if (!mReleasedFontGroup) {
 #ifndef RELEASE_BUILD
         gfxTextPerfMetrics *tp = mFontGroup->GetTextPerfMetrics();
         if (tp) {
             tp->current.textrunDestr++;
         }
 #endif
         NS_RELEASE(mFontGroup);
     }
     MOZ_COUNT_DTOR(gfxTextRun);
 }
 void
 gfxTextRun::ReleaseFontGroup()
 {
     NS_ASSERTION(!mReleasedFontGroup, "doubly released!");
     NS_RELEASE(mFontGroup);
     mReleasedFontGroup = true;
 }
 bool
 gfxTextRun::SetPotentialLineBreaks(uint32_t aStart, uint32_t aLength,
                                    uint8_t *aBreakBefore,
                                    gfxContext *aRefContext)
 {
     NS_ASSERTION(aStart + aLength <= GetLength(), "Overflow");
     uint32_t changed = 0;
     uint32_t i;
     CompressedGlyph *charGlyphs = mCharacterGlyphs + aStart;
     for (i = 0; i < aLength; ++i) {
         uint8_t canBreak = aBreakBefore[i];
         if (canBreak && !charGlyphs[i].IsClusterStart()) {
             // This can happen ... there is no guarantee that our linebreaking rules
             // align with the platform's idea of what constitutes a cluster.
             NS_WARNING("Break suggested inside cluster!");
             canBreak = CompressedGlyph::FLAG_BREAK_TYPE_NONE;
         }
         changed |= charGlyphs[i].SetCanBreakBefore(canBreak);
     }
     return changed != 0;
 }
 gfxTextRun::LigatureData
 gfxTextRun::ComputeLigatureData(uint32_t aPartStart, uint32_t aPartEnd,
                                 PropertyProvider *aProvider)
 {
     NS_ASSERTION(aPartStart < aPartEnd, "Computing ligature data for empty range");
     NS_ASSERTION(aPartEnd <= GetLength(), "Character length overflow");
     LigatureData result;
     CompressedGlyph *charGlyphs = mCharacterGlyphs;
     uint32_t i;
     for (i = aPartStart; !charGlyphs[i].IsLigatureGroupStart(); --i) {
         NS_ASSERTION(i > 0, "Ligature at the start of the run??");
     }
     result.mLigatureStart = i;
     for (i = aPartStart + 1; i < GetLength() && !charGlyphs[i].IsLigatureGroupStart(); ++i) {
     }
     result.mLigatureEnd = i;
     int32_t ligatureWidth =
         GetAdvanceForGlyphs(result.mLigatureStart, result.mLigatureEnd);
     // Count the number of started clusters we have seen
     uint32_t totalClusterCount = 0;
     uint32_t partClusterIndex = 0;
     uint32_t partClusterCount = 0;
     for (i = result.mLigatureStart; i < result.mLigatureEnd; ++i) {
         // Treat the first character of the ligature as the start of a
         // cluster for our purposes of allocating ligature width to its
         // characters.
         if (i == result.mLigatureStart || charGlyphs[i].IsClusterStart()) {
             ++totalClusterCount;
             if (i < aPartStart) {
                 ++partClusterIndex;
             } else if (i < aPartEnd) {
                 ++partClusterCount;
             }
         }
     }
     NS_ASSERTION(totalClusterCount > 0, "Ligature involving no clusters??");
     result.mPartAdvance = partClusterIndex * (ligatureWidth / totalClusterCount);
     result.mPartWidth = partClusterCount * (ligatureWidth / totalClusterCount);
     // Any rounding errors are apportioned to the final part of the ligature,
     // so that measuring all parts of a ligature and summing them is equal to
     // the ligature width.
     if (aPartEnd == result.mLigatureEnd) {
         gfxFloat allParts = totalClusterCount * (ligatureWidth / totalClusterCount);
         result.mPartWidth += ligatureWidth - allParts;
     }
     if (partClusterCount == 0) {
         // nothing to draw
         result.mClipBeforePart = result.mClipAfterPart = true;
     } else {
         // Determine whether we should clip before or after this part when
         // drawing its slice of the ligature.
         // We need to clip before the part if any cluster is drawn before
         // this part.
         result.mClipBeforePart = partClusterIndex > 0;
         // We need to clip after the part if any cluster is drawn after
         // this part.
         result.mClipAfterPart = partClusterIndex + partClusterCount < totalClusterCount;
     }
     if (aProvider && (mFlags & gfxTextRunFactory::TEXT_ENABLE_SPACING)) {
         gfxFont::Spacing spacing;
         if (aPartStart == result.mLigatureStart) {
             aProvider->GetSpacing(aPartStart, 1, &spacing);
             result.mPartWidth += spacing.mBefore;
         }
         if (aPartEnd == result.mLigatureEnd) {
             aProvider->GetSpacing(aPartEnd - 1, 1, &spacing);
             result.mPartWidth += spacing.mAfter;
         }
     }
     return result;
 }
 gfxFloat
 gfxTextRun::ComputePartialLigatureWidth(uint32_t aPartStart, uint32_t aPartEnd,
                                         PropertyProvider *aProvider)
 {
     if (aPartStart >= aPartEnd)
         return 0;
     LigatureData data = ComputeLigatureData(aPartStart, aPartEnd, aProvider);
     return data.mPartWidth;
 }
 int32_t
 gfxTextRun::GetAdvanceForGlyphs(uint32_t aStart, uint32_t aEnd)
 {
     const CompressedGlyph *glyphData = mCharacterGlyphs + aStart;
     int32_t advance = 0;
     uint32_t i;
     for (i = aStart; i < aEnd; ++i, ++glyphData) {
         if (glyphData->IsSimpleGlyph()) {
             advance += glyphData->GetSimpleAdvance();
         } else {
             uint32_t glyphCount = glyphData->GetGlyphCount();
             if (glyphCount == 0) {
                 continue;
             }
             const DetailedGlyph *details = GetDetailedGlyphs(i);
             if (details) {
                 uint32_t j;
                 for (j = 0; j < glyphCount; ++j, ++details) {
                     advance += details->mAdvance;
                 }
             }
         }
     }
     return advance;
 }
 static void
 GetAdjustedSpacing(gfxTextRun *aTextRun, uint32_t aStart, uint32_t aEnd,
                    gfxTextRun::PropertyProvider *aProvider,
                    gfxTextRun::PropertyProvider::Spacing *aSpacing)
 {
     if (aStart >= aEnd)
         return;
     aProvider->GetSpacing(aStart, aEnd - aStart, aSpacing);
 #ifdef DEBUG
     // Check to see if we have spacing inside ligatures
     const gfxTextRun::CompressedGlyph *charGlyphs = aTextRun->GetCharacterGlyphs();
     uint32_t i;
     for (i = aStart; i < aEnd; ++i) {
         if (!charGlyphs[i].IsLigatureGroupStart()) {
             NS_ASSERTION(i == aStart || aSpacing[i - aStart].mBefore == 0,
                          "Before-spacing inside a ligature!");
             NS_ASSERTION(i - 1 <= aStart || aSpacing[i - 1 - aStart].mAfter == 0,
                          "After-spacing inside a ligature!");
         }
     }
 #endif
 }
 bool
 gfxTextRun::GetAdjustedSpacingArray(uint32_t aStart, uint32_t aEnd,
                                     PropertyProvider *aProvider,
                                     uint32_t aSpacingStart, uint32_t aSpacingEnd,
                                     nsTArray<PropertyProvider::Spacing> *aSpacing)
 {
     if (!aProvider || !(mFlags & gfxTextRunFactory::TEXT_ENABLE_SPACING))
         return false;
     if (!aSpacing->AppendElements(aEnd - aStart))
         return false;
     memset(aSpacing->Elements(), 0, sizeof(gfxFont::Spacing)*(aSpacingStart - aStart));
     GetAdjustedSpacing(this, aSpacingStart, aSpacingEnd, aProvider,
                        aSpacing->Elements() + aSpacingStart - aStart);
     memset(aSpacing->Elements() + aSpacingEnd - aStart, 0, sizeof(gfxFont::Spacing)*(aEnd - aSpacingEnd));
     return true;
 }
 void
 gfxTextRun::ShrinkToLigatureBoundaries(uint32_t *aStart, uint32_t *aEnd)
 {
     if (*aStart >= *aEnd)
         return;
     CompressedGlyph *charGlyphs = mCharacterGlyphs;
     while (*aStart < *aEnd && !charGlyphs[*aStart].IsLigatureGroupStart()) {
         ++(*aStart);
     }
     if (*aEnd < GetLength()) {
         while (*aEnd > *aStart && !charGlyphs[*aEnd].IsLigatureGroupStart()) {
             --(*aEnd);
         }
     }
 }
 void
 gfxTextRun::DrawGlyphs(gfxFont *aFont, gfxContext *aContext,
                        DrawMode aDrawMode, gfxPoint *aPt,
                        gfxTextContextPaint *aContextPaint,
                        uint32_t aStart, uint32_t aEnd,
                        PropertyProvider *aProvider,
                        uint32_t aSpacingStart, uint32_t aSpacingEnd,
                        gfxTextRunDrawCallbacks *aCallbacks)
 {
     nsAutoTArray<PropertyProvider::Spacing,200> spacingBuffer;
     bool haveSpacing = GetAdjustedSpacingArray(aStart, aEnd, aProvider,
         aSpacingStart, aSpacingEnd, &spacingBuffer);
     aFont->Draw(this, aStart, aEnd, aContext, aDrawMode, aPt,
                 haveSpacing ? spacingBuffer.Elements() : nullptr, aContextPaint,
                 aCallbacks);
 }
 static void
 ClipPartialLigature(gfxTextRun *aTextRun, gfxFloat *aLeft, gfxFloat *aRight,
                     gfxFloat aXOrigin, gfxTextRun::LigatureData *aLigature)
 {
     if (aLigature->mClipBeforePart) {
         if (aTextRun->IsRightToLeft()) {
             *aRight = std::min(*aRight, aXOrigin);
         } else {
             *aLeft = std::max(*aLeft, aXOrigin);
         }
     }
     if (aLigature->mClipAfterPart) {
         gfxFloat endEdge = aXOrigin + aTextRun->GetDirection()*aLigature->mPartWidth;
         if (aTextRun->IsRightToLeft()) {
             *aLeft = std::max(*aLeft, endEdge);
         } else {
             *aRight = std::min(*aRight, endEdge);
         }
     }
 }
 void
 gfxTextRun::DrawPartialLigature(gfxFont *aFont, gfxContext *aCtx,
                                 uint32_t aStart, uint32_t aEnd,
                                 gfxPoint *aPt,
                                 PropertyProvider *aProvider,
                                 gfxTextRunDrawCallbacks *aCallbacks)
 {
     if (aStart >= aEnd)
         return;
     // Draw partial ligature. We hack this by clipping the ligature.
     LigatureData data = ComputeLigatureData(aStart, aEnd, aProvider);
     gfxRect clipExtents = aCtx->GetClipExtents();
     gfxFloat left = clipExtents.X()*mAppUnitsPerDevUnit;
     gfxFloat right = clipExtents.XMost()*mAppUnitsPerDevUnit;
     ClipPartialLigature(this, &left, &right, aPt->x, &data);
     {
       // Need to preserve the path, otherwise this can break canvas text-on-path;
       // in general it seems like a good thing, as naive callers probably won't
       // expect gfxTextRun::Draw to implicitly destroy the current path.
       gfxContextPathAutoSaveRestore savePath(aCtx);
       // use division here to ensure that when the rect is aligned on multiples
       // of mAppUnitsPerDevUnit, we clip to true device unit boundaries.
       // Also, make sure we snap the rectangle to device pixels.
       aCtx->Save();
       aCtx->NewPath();
       aCtx->Rectangle(gfxRect(left / mAppUnitsPerDevUnit,
                               clipExtents.Y(),
                               (right - left) / mAppUnitsPerDevUnit,
                               clipExtents.Height()), true);
       aCtx->Clip();
     }
     gfxFloat direction = GetDirection();
     gfxPoint pt(aPt->x - direction*data.mPartAdvance, aPt->y);
     DrawGlyphs(aFont, aCtx,
                aCallbacks ? DrawMode::GLYPH_PATH : DrawMode::GLYPH_FILL, &pt,
                nullptr, data.mLigatureStart, data.mLigatureEnd, aProvider,
                aStart, aEnd, aCallbacks);
     aCtx->Restore();
     aPt->x += direction*data.mPartWidth;
 }
 // returns true if a glyph run is using a font with synthetic bolding enabled, false otherwise
 static bool
 HasSyntheticBold(gfxTextRun *aRun, uint32_t aStart, uint32_t aLength)
 {
     gfxTextRun::GlyphRunIterator iter(aRun, aStart, aLength);
     while (iter.NextRun()) {
         gfxFont *font = iter.GetGlyphRun()->mFont;
         if (font && font->IsSyntheticBold()) {
             return true;
         }
     }
     return false;
 }
 // returns true if color is non-opaque (i.e. alpha != 1.0) or completely transparent, false otherwise
 // if true, color is set on output
 static bool
 HasNonOpaqueColor(gfxContext *aContext, gfxRGBA& aCurrentColor)
 {
     if (aContext->GetDeviceColor(aCurrentColor)) {
         if (aCurrentColor.a < 1.0 && aCurrentColor.a > 0.0) {
             return true;
         }
     }
     return false;
 }
 // helper class for double-buffering drawing with non-opaque color
 struct BufferAlphaColor {
     BufferAlphaColor(gfxContext *aContext)
         : mContext(aContext)
     {
     }
     ~BufferAlphaColor() {}
     void PushSolidColor(const gfxRect& aBounds, const gfxRGBA& aAlphaColor, uint32_t appsPerDevUnit)
     {
         mContext->Save();
         mContext->NewPath();
         mContext->Rectangle(gfxRect(aBounds.X() / appsPerDevUnit,
                     aBounds.Y() / appsPerDevUnit,
                     aBounds.Width() / appsPerDevUnit,
                     aBounds.Height() / appsPerDevUnit), true);
         mContext->Clip();
         mContext->SetColor(gfxRGBA(aAlphaColor.r, aAlphaColor.g, aAlphaColor.b));
         mContext->PushGroup(gfxContentType::COLOR_ALPHA);
         mAlpha = aAlphaColor.a;
     }
     void PopAlpha()
     {
         // pop the text, using the color alpha as the opacity
         mContext->PopGroupToSource();
         mContext->SetOperator(gfxContext::OPERATOR_OVER);
         mContext->Paint(mAlpha);
         mContext->Restore();
     }
     gfxContext *mContext;
     gfxFloat mAlpha;
 };
 void
 gfxTextRun::Draw(gfxContext *aContext, gfxPoint aPt, DrawMode aDrawMode,
                  uint32_t aStart, uint32_t aLength,
                  PropertyProvider *aProvider, gfxFloat *aAdvanceWidth,
                  gfxTextContextPaint *aContextPaint,
                  gfxTextRunDrawCallbacks *aCallbacks)
 {
     NS_ASSERTION(aStart + aLength <= GetLength(), "Substring out of range");
     NS_ASSERTION(aDrawMode == DrawMode::GLYPH_PATH || !(int(aDrawMode) & int(DrawMode::GLYPH_PATH)),
                  "GLYPH_PATH cannot be used with GLYPH_FILL, GLYPH_STROKE or GLYPH_STROKE_UNDERNEATH");
     NS_ASSERTION(aDrawMode == DrawMode::GLYPH_PATH || !aCallbacks, "callback must not be specified unless using GLYPH_PATH");
     bool skipDrawing = mSkipDrawing;
     if (aDrawMode == DrawMode::GLYPH_FILL) {
         gfxRGBA currentColor;
         if (aContext->GetDeviceColor(currentColor) && currentColor.a == 0) {
             skipDrawing = true;
         }
     }
     gfxFloat direction = GetDirection();
     if (skipDrawing) {
         // We don't need to draw anything;
         // but if the caller wants advance width, we need to compute it here
         if (aAdvanceWidth) {
             gfxTextRun::Metrics metrics = MeasureText(aStart, aLength,
                                                       gfxFont::LOOSE_INK_EXTENTS,
                                                       aContext, aProvider);
             *aAdvanceWidth = metrics.mAdvanceWidth * direction;
         }
         // return without drawing
         return;
     }
     gfxPoint pt = aPt;
     // synthetic bolding draws glyphs twice ==> colors with opacity won't draw correctly unless first drawn without alpha
     BufferAlphaColor syntheticBoldBuffer(aContext);
     gfxRGBA currentColor;
     bool needToRestore = false;
     if (aDrawMode == DrawMode::GLYPH_FILL && HasNonOpaqueColor(aContext, currentColor)
                                           && HasSyntheticBold(this, aStart, aLength)) {
         needToRestore = true;
         // measure text, use the bounding box
         gfxTextRun::Metrics metrics = MeasureText(aStart, aLength, gfxFont::LOOSE_INK_EXTENTS,
                                                   aContext, aProvider);
         metrics.mBoundingBox.MoveBy(aPt);
         syntheticBoldBuffer.PushSolidColor(metrics.mBoundingBox, currentColor, GetAppUnitsPerDevUnit());
     }
     GlyphRunIterator iter(this, aStart, aLength);
     while (iter.NextRun()) {
         gfxFont *font = iter.GetGlyphRun()->mFont;
         uint32_t start = iter.GetStringStart();
         uint32_t end = iter.GetStringEnd();
         uint32_t ligatureRunStart = start;
         uint32_t ligatureRunEnd = end;
         ShrinkToLigatureBoundaries(&ligatureRunStart, &ligatureRunEnd);
         bool drawPartial = aDrawMode == DrawMode::GLYPH_FILL ||
                            (aDrawMode == DrawMode::GLYPH_PATH && aCallbacks);
         if (drawPartial) {
             DrawPartialLigature(font, aContext, start, ligatureRunStart, &pt,
                                 aProvider, aCallbacks);
         }
         DrawGlyphs(font, aContext, aDrawMode, &pt, aContextPaint, ligatureRunStart,
                    ligatureRunEnd, aProvider, ligatureRunStart, ligatureRunEnd,
                    aCallbacks);
         if (drawPartial) {
             DrawPartialLigature(font, aContext, ligatureRunEnd, end, &pt,
                                 aProvider, aCallbacks);
         }
     }
     // composite result when synthetic bolding used
     if (needToRestore) {
         syntheticBoldBuffer.PopAlpha();
     }
     if (aAdvanceWidth) {
         *aAdvanceWidth = (pt.x - aPt.x)*direction;
     }
 }
 void
 gfxTextRun::AccumulateMetricsForRun(gfxFont *aFont,
                                     uint32_t aStart, uint32_t aEnd,
                                     gfxFont::BoundingBoxType aBoundingBoxType,
                                     gfxContext *aRefContext,
                                     PropertyProvider *aProvider,
                                     uint32_t aSpacingStart, uint32_t aSpacingEnd,
                                     Metrics *aMetrics)
 {
     nsAutoTArray<PropertyProvider::Spacing,200> spacingBuffer;
     bool haveSpacing = GetAdjustedSpacingArray(aStart, aEnd, aProvider,
         aSpacingStart, aSpacingEnd, &spacingBuffer);
     Metrics metrics = aFont->Measure(this, aStart, aEnd, aBoundingBoxType, aRefContext,
                                      haveSpacing ? spacingBuffer.Elements() : nullptr);
     aMetrics->CombineWith(metrics, IsRightToLeft());
 }
 void
 gfxTextRun::AccumulatePartialLigatureMetrics(gfxFont *aFont,
     uint32_t aStart, uint32_t aEnd,
     gfxFont::BoundingBoxType aBoundingBoxType, gfxContext *aRefContext,
     PropertyProvider *aProvider, Metrics *aMetrics)
 {
     if (aStart >= aEnd)
         return;
     // Measure partial ligature. We hack this by clipping the metrics in the
     // same way we clip the drawing.
     LigatureData data = ComputeLigatureData(aStart, aEnd, aProvider);
     // First measure the complete ligature
     Metrics metrics;
     AccumulateMetricsForRun(aFont, data.mLigatureStart, data.mLigatureEnd,
                             aBoundingBoxType, aRefContext,
                             aProvider, aStart, aEnd, &metrics);
     // Clip the bounding box to the ligature part
     gfxFloat bboxLeft = metrics.mBoundingBox.X();
     gfxFloat bboxRight = metrics.mBoundingBox.XMost();
     // Where we are going to start "drawing" relative to our left baseline origin
     gfxFloat origin = IsRightToLeft() ? metrics.mAdvanceWidth - data.mPartAdvance : 0;
     ClipPartialLigature(this, &bboxLeft, &bboxRight, origin, &data);
     metrics.mBoundingBox.x = bboxLeft;
     metrics.mBoundingBox.width = bboxRight - bboxLeft;
     // mBoundingBox is now relative to the left baseline origin for the entire
     // ligature. Shift it left.
     metrics.mBoundingBox.x -=
         IsRightToLeft() ? metrics.mAdvanceWidth - (data.mPartAdvance + data.mPartWidth)
             : data.mPartAdvance;
     metrics.mAdvanceWidth = data.mPartWidth;
     aMetrics->CombineWith(metrics, IsRightToLeft());
 }
 gfxTextRun::Metrics
 gfxTextRun::MeasureText(uint32_t aStart, uint32_t aLength,
                         gfxFont::BoundingBoxType aBoundingBoxType,
                         gfxContext *aRefContext,
                         PropertyProvider *aProvider)
 {
     NS_ASSERTION(aStart + aLength <= GetLength(), "Substring out of range");
     Metrics accumulatedMetrics;
     GlyphRunIterator iter(this, aStart, aLength);
     while (iter.NextRun()) {
         gfxFont *font = iter.GetGlyphRun()->mFont;
         uint32_t start = iter.GetStringStart();
         uint32_t end = iter.GetStringEnd();
         uint32_t ligatureRunStart = start;
         uint32_t ligatureRunEnd = end;
         ShrinkToLigatureBoundaries(&ligatureRunStart, &ligatureRunEnd);
         AccumulatePartialLigatureMetrics(font, start, ligatureRunStart,
             aBoundingBoxType, aRefContext, aProvider, &accumulatedMetrics);
         // XXX This sucks. We have to get glyph extents just so we can detect
         // glyphs outside the font box, even when aBoundingBoxType is LOOSE,
         // even though in almost all cases we could get correct results just
         // by getting some ascent/descent from the font and using our stored
         // advance widths.
         AccumulateMetricsForRun(font,
             ligatureRunStart, ligatureRunEnd, aBoundingBoxType,
             aRefContext, aProvider, ligatureRunStart, ligatureRunEnd,
             &accumulatedMetrics);
         AccumulatePartialLigatureMetrics(font, ligatureRunEnd, end,
             aBoundingBoxType, aRefContext, aProvider, &accumulatedMetrics);
     }
     return accumulatedMetrics;
 }
 #define MEASUREMENT_BUFFER_SIZE 100
 uint32_t
 gfxTextRun::BreakAndMeasureText(uint32_t aStart, uint32_t aMaxLength,
                                 bool aLineBreakBefore, gfxFloat aWidth,
                                 PropertyProvider *aProvider,
                                 bool aSuppressInitialBreak,
                                 gfxFloat *aTrimWhitespace,
                                 Metrics *aMetrics,
                                 gfxFont::BoundingBoxType aBoundingBoxType,
                                 gfxContext *aRefContext,
                                 bool *aUsedHyphenation,
                                 uint32_t *aLastBreak,
                                 bool aCanWordWrap,
                                 gfxBreakPriority *aBreakPriority)
 {
     aMaxLength = std::min(aMaxLength, GetLength() - aStart);
     NS_ASSERTION(aStart + aMaxLength <= GetLength(), "Substring out of range");
     uint32_t bufferStart = aStart;
     uint32_t bufferLength = std::min<uint32_t>(aMaxLength, MEASUREMENT_BUFFER_SIZE);
     PropertyProvider::Spacing spacingBuffer[MEASUREMENT_BUFFER_SIZE];
     bool haveSpacing = aProvider && (mFlags & gfxTextRunFactory::TEXT_ENABLE_SPACING) != 0;
     if (haveSpacing) {
         GetAdjustedSpacing(this, bufferStart, bufferStart + bufferLength, aProvider,
                            spacingBuffer);
     }
     bool hyphenBuffer[MEASUREMENT_BUFFER_SIZE];
     bool haveHyphenation = aProvider &&
         (aProvider->GetHyphensOption() == NS_STYLE_HYPHENS_AUTO ||
          (aProvider->GetHyphensOption() == NS_STYLE_HYPHENS_MANUAL &&
           (mFlags & gfxTextRunFactory::TEXT_ENABLE_HYPHEN_BREAKS) != 0));
     if (haveHyphenation) {
         aProvider->GetHyphenationBreaks(bufferStart, bufferLength,
                                         hyphenBuffer);
     }
     gfxFloat width = 0;
     gfxFloat advance = 0;
     // The number of space characters that can be trimmed
     uint32_t trimmableChars = 0;
     // The amount of space removed by ignoring trimmableChars
     gfxFloat trimmableAdvance = 0;
     int32_t lastBreak = -1;
     int32_t lastBreakTrimmableChars = -1;
     gfxFloat lastBreakTrimmableAdvance = -1;
     bool aborted = false;
     uint32_t end = aStart + aMaxLength;
     bool lastBreakUsedHyphenation = false;
     uint32_t ligatureRunStart = aStart;
     uint32_t ligatureRunEnd = end;
     ShrinkToLigatureBoundaries(&ligatureRunStart, &ligatureRunEnd);
     uint32_t i;
     for (i = aStart; i < end; ++i) {
         if (i >= bufferStart + bufferLength) {
             // Fetch more spacing and hyphenation data
             bufferStart = i;
             bufferLength = std::min(aStart + aMaxLength, i + MEASUREMENT_BUFFER_SIZE) - i;
             if (haveSpacing) {
                 GetAdjustedSpacing(this, bufferStart, bufferStart + bufferLength, aProvider,
                                    spacingBuffer);
             }
             if (haveHyphenation) {
                 aProvider->GetHyphenationBreaks(bufferStart, bufferLength,
                                                 hyphenBuffer);
             }
         }
         // There can't be a word-wrap break opportunity at the beginning of the
         // line: if the width is too small for even one character to fit, it
         // could be the first and last break opportunity on the line, and that
         // would trigger an infinite loop.
         if (!aSuppressInitialBreak || i > aStart) {
             bool atNaturalBreak = mCharacterGlyphs[i].CanBreakBefore() == 1;
             bool atHyphenationBreak =
                 !atNaturalBreak && haveHyphenation && hyphenBuffer[i - bufferStart];
             bool atBreak = atNaturalBreak || atHyphenationBreak;
             bool wordWrapping =
                 aCanWordWrap && mCharacterGlyphs[i].IsClusterStart() &&
                 *aBreakPriority <= gfxBreakPriority::eWordWrapBreak;
             if (atBreak || wordWrapping) {
                 gfxFloat hyphenatedAdvance = advance;
                 if (atHyphenationBreak) {
                     hyphenatedAdvance += aProvider->GetHyphenWidth();
                 }
                 if (lastBreak < 0 || width + hyphenatedAdvance - trimmableAdvance <= aWidth) {
                     // We can break here.
                     lastBreak = i;
                     lastBreakTrimmableChars = trimmableChars;
                     lastBreakTrimmableAdvance = trimmableAdvance;
                     lastBreakUsedHyphenation = atHyphenationBreak;
                     *aBreakPriority = atBreak ? gfxBreakPriority::eNormalBreak
                                               : gfxBreakPriority::eWordWrapBreak;
                 }
                 width += advance;
                 advance = 0;
                 if (width - trimmableAdvance > aWidth) {
                     // No more text fits. Abort
                     aborted = true;
                     break;
                 }
             }
         }
         gfxFloat charAdvance;
         if (i >= ligatureRunStart && i < ligatureRunEnd) {
             charAdvance = GetAdvanceForGlyphs(i, i + 1);
             if (haveSpacing) {
                 PropertyProvider::Spacing *space = &spacingBuffer[i - bufferStart];
                 charAdvance += space->mBefore + space->mAfter;
             }
         } else {
             charAdvance = ComputePartialLigatureWidth(i, i + 1, aProvider);
         }
         advance += charAdvance;
         if (aTrimWhitespace) {
             if (mCharacterGlyphs[i].CharIsSpace()) {
                 ++trimmableChars;
                 trimmableAdvance += charAdvance;
             } else {
                 trimmableAdvance = 0;
                 trimmableChars = 0;
             }
         }
     }
     if (!aborted) {
         width += advance;
     }
     // There are three possibilities:
     // 1) all the text fit (width <= aWidth)
     // 2) some of the text fit up to a break opportunity (width > aWidth && lastBreak >= 0)
     // 3) none of the text fits before a break opportunity (width > aWidth && lastBreak < 0)
     uint32_t charsFit;
     bool usedHyphenation = false;
     if (width - trimmableAdvance <= aWidth) {
         charsFit = aMaxLength;
     } else if (lastBreak >= 0) {
         charsFit = lastBreak - aStart;
         trimmableChars = lastBreakTrimmableChars;
         trimmableAdvance = lastBreakTrimmableAdvance;
         usedHyphenation = lastBreakUsedHyphenation;
     } else {
         charsFit = aMaxLength;
     }
     if (aMetrics) {
         *aMetrics = MeasureText(aStart, charsFit - trimmableChars,
             aBoundingBoxType, aRefContext, aProvider);
     }
     if (aTrimWhitespace) {
         *aTrimWhitespace = trimmableAdvance;
     }
     if (aUsedHyphenation) {
         *aUsedHyphenation = usedHyphenation;
     }
     if (aLastBreak && charsFit == aMaxLength) {
         if (lastBreak < 0) {
             *aLastBreak = UINT32_MAX;
         } else {
             *aLastBreak = lastBreak - aStart;
         }
     }
     return charsFit;
 }
 gfxFloat
 gfxTextRun::GetAdvanceWidth(uint32_t aStart, uint32_t aLength,
                             PropertyProvider *aProvider)
 {
     NS_ASSERTION(aStart + aLength <= GetLength(), "Substring out of range");
     uint32_t ligatureRunStart = aStart;
     uint32_t ligatureRunEnd = aStart + aLength;
     ShrinkToLigatureBoundaries(&ligatureRunStart, &ligatureRunEnd);
     gfxFloat result = ComputePartialLigatureWidth(aStart, ligatureRunStart, aProvider) +
                       ComputePartialLigatureWidth(ligatureRunEnd, aStart + aLength, aProvider);
     // Account for all remaining spacing here. This is more efficient than
     // processing it along with the glyphs.
     if (aProvider && (mFlags & gfxTextRunFactory::TEXT_ENABLE_SPACING)) {
         uint32_t i;
         nsAutoTArray<PropertyProvider::Spacing,200> spacingBuffer;
         if (spacingBuffer.AppendElements(aLength)) {
             GetAdjustedSpacing(this, ligatureRunStart, ligatureRunEnd, aProvider,
                                spacingBuffer.Elements());
             for (i = 0; i < ligatureRunEnd - ligatureRunStart; ++i) {
                 PropertyProvider::Spacing *space = &spacingBuffer[i];
                 result += space->mBefore + space->mAfter;
             }
         }
     }
     return result + GetAdvanceForGlyphs(ligatureRunStart, ligatureRunEnd);
 }
 bool
 gfxTextRun::SetLineBreaks(uint32_t aStart, uint32_t aLength,
                           bool aLineBreakBefore, bool aLineBreakAfter,
                           gfxFloat *aAdvanceWidthDelta,
                           gfxContext *aRefContext)
 {
     // Do nothing because our shaping does not currently take linebreaks into
     // account. There is no change in advance width.
     if (aAdvanceWidthDelta) {
         *aAdvanceWidthDelta = 0;
     }
     return false;
 }
 uint32_t
 gfxTextRun::FindFirstGlyphRunContaining(uint32_t aOffset)
 {
     NS_ASSERTION(aOffset <= GetLength(), "Bad offset looking for glyphrun");
     NS_ASSERTION(GetLength() == 0 || mGlyphRuns.Length() > 0,
                  "non-empty text but no glyph runs present!");
     if (aOffset == GetLength())
         return mGlyphRuns.Length();
     uint32_t start = 0;
     uint32_t end = mGlyphRuns.Length();
     while (end - start > 1) {
         uint32_t mid = (start + end)/2;
         if (mGlyphRuns[mid].mCharacterOffset <= aOffset) {
             start = mid;
         } else {
             end = mid;
         }
     }
     NS_ASSERTION(mGlyphRuns[start].mCharacterOffset <= aOffset,
                  "Hmm, something went wrong, aOffset should have been found");
     return start;
 }
 nsresult
 gfxTextRun::AddGlyphRun(gfxFont *aFont, uint8_t aMatchType,
                         uint32_t aUTF16Offset, bool aForceNewRun)
 {
     NS_ASSERTION(aFont, "adding glyph run for null font!");
     if (!aFont) {
         return NS_OK;
     }
     uint32_t numGlyphRuns = mGlyphRuns.Length();
     if (!aForceNewRun && numGlyphRuns > 0) {
         GlyphRun *lastGlyphRun = &mGlyphRuns[numGlyphRuns - 1];
         NS_ASSERTION(lastGlyphRun->mCharacterOffset <= aUTF16Offset,
                      "Glyph runs out of order (and run not forced)");
         // Don't append a run if the font is already the one we want
         if (lastGlyphRun->mFont == aFont &&
             lastGlyphRun->mMatchType == aMatchType)
         {
             return NS_OK;
         }
         // If the offset has not changed, avoid leaving a zero-length run
         // by overwriting the last entry instead of appending...
         if (lastGlyphRun->mCharacterOffset == aUTF16Offset) {
             // ...except that if the run before the last entry had the same
             // font as the new one wants, merge with it instead of creating
             // adjacent runs with the same font
             if (numGlyphRuns > 1 &&
                 mGlyphRuns[numGlyphRuns - 2].mFont == aFont &&
                 mGlyphRuns[numGlyphRuns - 2].mMatchType == aMatchType)
             {
                 mGlyphRuns.TruncateLength(numGlyphRuns - 1);
                 return NS_OK;
             }
             lastGlyphRun->mFont = aFont;
             lastGlyphRun->mMatchType = aMatchType;
             return NS_OK;
         }
     }
     NS_ASSERTION(aForceNewRun || numGlyphRuns > 0 || aUTF16Offset == 0,
                  "First run doesn't cover the first character (and run not forced)?");
     GlyphRun *glyphRun = mGlyphRuns.AppendElement();
     if (!glyphRun)
         return NS_ERROR_OUT_OF_MEMORY;
     glyphRun->mFont = aFont;
     glyphRun->mCharacterOffset = aUTF16Offset;
     glyphRun->mMatchType = aMatchType;
     return NS_OK;
 }
 void
 gfxTextRun::SortGlyphRuns()
 {
     if (mGlyphRuns.Length() <= 1)
         return;
     nsTArray<GlyphRun> runs(mGlyphRuns);
     GlyphRunOffsetComparator comp;
     runs.Sort(comp);
     // Now copy back, coalescing adjacent glyph runs that have the same font
     mGlyphRuns.Clear();
     uint32_t i, count = runs.Length();
     for (i = 0; i < count; ++i) {
         // a GlyphRun with the same font as the previous GlyphRun can just
         // be skipped; the last GlyphRun will cover its character range.
         if (i == 0 || runs[i].mFont != runs[i - 1].mFont) {
             mGlyphRuns.AppendElement(runs[i]);
             // If two fonts have the same character offset, Sort() will have
             // randomized the order.
             NS_ASSERTION(i == 0 ||
                          runs[i].mCharacterOffset !=
                          runs[i - 1].mCharacterOffset,
                          "Two fonts for the same run, glyph indices may not match the font");
         }
     }
 }
 // Note that SanitizeGlyphRuns scans all glyph runs in the textrun;
 // therefore we only call it once, at the end of textrun construction,
 // NOT incrementally as each glyph run is added (bug 680402).
 void
 gfxTextRun::SanitizeGlyphRuns()
 {
     if (mGlyphRuns.Length() <= 1)
         return;
     // If any glyph run starts with ligature-continuation characters, we need to advance it
     // to the first "real" character to avoid drawing partial ligature glyphs from wrong font
     // (seen with U+FEFF in reftest 474417-1, as Core Text eliminates the glyph, which makes
     // it appear as if a ligature has been formed)
     int32_t i, lastRunIndex = mGlyphRuns.Length() - 1;
     const CompressedGlyph *charGlyphs = mCharacterGlyphs;
     for (i = lastRunIndex; i >= 0; --i) {
         GlyphRun& run = mGlyphRuns[i];
         while (charGlyphs[run.mCharacterOffset].IsLigatureContinuation() &&
                run.mCharacterOffset < GetLength()) {
             run.mCharacterOffset++;
         }
         // if the run has become empty, eliminate it
         if ((i < lastRunIndex &&
              run.mCharacterOffset >= mGlyphRuns[i+1].mCharacterOffset) ||
             (i == lastRunIndex && run.mCharacterOffset == GetLength())) {
             mGlyphRuns.RemoveElementAt(i);
             --lastRunIndex;
         }
     }
 }
 uint32_t
 gfxTextRun::CountMissingGlyphs()
 {
     uint32_t i;
     uint32_t count = 0;
     for (i = 0; i < GetLength(); ++i) {
         if (mCharacterGlyphs[i].IsMissing()) {
             ++count;
         }
     }
     return count;
 }
 gfxTextRun::DetailedGlyph *
 gfxTextRun::AllocateDetailedGlyphs(uint32_t aIndex, uint32_t aCount)
 {
     NS_ASSERTION(aIndex < GetLength(), "Index out of range");
     if (!mDetailedGlyphs) {
         mDetailedGlyphs = new DetailedGlyphStore();
     }
     DetailedGlyph *details = mDetailedGlyphs->Allocate(aIndex, aCount);
     if (!details) {
         mCharacterGlyphs[aIndex].SetMissing(0);
         return nullptr;
     }
     return details;
 }
 void
 gfxTextRun::CopyGlyphDataFrom(gfxShapedWord *aShapedWord, uint32_t aOffset)
 {
     uint32_t wordLen = aShapedWord->GetLength();
     NS_ASSERTION(aOffset + wordLen <= GetLength(),
                  "word overruns end of textrun!");
     CompressedGlyph *charGlyphs = GetCharacterGlyphs();
     const CompressedGlyph *wordGlyphs = aShapedWord->GetCharacterGlyphs();
     if (aShapedWord->HasDetailedGlyphs()) {
         for (uint32_t i = 0; i < wordLen; ++i, ++aOffset) {
             const CompressedGlyph& g = wordGlyphs[i];
             if (g.IsSimpleGlyph()) {
                 charGlyphs[aOffset] = g;
             } else {
                 const DetailedGlyph *details =
                     g.GetGlyphCount() > 0 ?
                         aShapedWord->GetDetailedGlyphs(i) : nullptr;
                 SetGlyphs(aOffset, g, details);
             }
         }
     } else {
         memcpy(charGlyphs + aOffset, wordGlyphs,
                wordLen * sizeof(CompressedGlyph));
     }
 }
 void
 gfxTextRun::CopyGlyphDataFrom(gfxTextRun *aSource, uint32_t aStart,
                               uint32_t aLength, uint32_t aDest)
 {
     NS_ASSERTION(aStart + aLength <= aSource->GetLength(),
                  "Source substring out of range");
     NS_ASSERTION(aDest + aLength <= GetLength(),
                  "Destination substring out of range");
     if (aSource->mSkipDrawing) {
         mSkipDrawing = true;
     }
     // Copy base glyph data, and DetailedGlyph data where present
     const CompressedGlyph *srcGlyphs = aSource->mCharacterGlyphs + aStart;
     CompressedGlyph *dstGlyphs = mCharacterGlyphs + aDest;
     for (uint32_t i = 0; i < aLength; ++i) {
         CompressedGlyph g = srcGlyphs[i];
         g.SetCanBreakBefore(!g.IsClusterStart() ?
             CompressedGlyph::FLAG_BREAK_TYPE_NONE :
             dstGlyphs[i].CanBreakBefore());
         if (!g.IsSimpleGlyph()) {
             uint32_t count = g.GetGlyphCount();
             if (count > 0) {
                 DetailedGlyph *dst = AllocateDetailedGlyphs(i + aDest, count);
                 if (dst) {
                     DetailedGlyph *src = aSource->GetDetailedGlyphs(i + aStart);
                     if (src) {
                         ::memcpy(dst, src, count * sizeof(DetailedGlyph));
                     } else {
                         g.SetMissing(0);
                     }
                 } else {
                     g.SetMissing(0);
                 }
             }
         }
         dstGlyphs[i] = g;
     }
     // Copy glyph runs
     GlyphRunIterator iter(aSource, aStart, aLength);
 #ifdef DEBUG
     gfxFont *lastFont = nullptr;
 #endif
     while (iter.NextRun()) {
         gfxFont *font = iter.GetGlyphRun()->mFont;
         NS_ASSERTION(font != lastFont, "Glyphruns not coalesced?");
 #ifdef DEBUG
         lastFont = font;
         uint32_t end = iter.GetStringEnd();
 #endif
         uint32_t start = iter.GetStringStart();
         // These used to be NS_ASSERTION()s, but WARNING is more appropriate.
         // Although it's unusual (and not desirable), it's possible for us to assign
         // different fonts to a base character and a following diacritic.
         // Example on OSX 10.5/10.6 with default fonts installed:
         //     data:text/html,<p style="font-family:helvetica, arial, sans-serif;">
         //                    &%23x043E;&%23x0486;&%23x20;&%23x043E;&%23x0486;
         // This means the rendering of the cluster will probably not be very good,
         // but it's the best we can do for now if the specified font only covered the
         // initial base character and not its applied marks.
         NS_WARN_IF_FALSE(aSource->IsClusterStart(start),
                          "Started font run in the middle of a cluster");
         NS_WARN_IF_FALSE(end == aSource->GetLength() || aSource->IsClusterStart(end),
                          "Ended font run in the middle of a cluster");
         nsresult rv = AddGlyphRun(font, iter.GetGlyphRun()->mMatchType,
                                   start - aStart + aDest, false);
         if (NS_FAILED(rv))
             return;
     }
 }
 void
 gfxTextRun::SetSpaceGlyph(gfxFont *aFont, gfxContext *aContext,
                           uint32_t aCharIndex)
 {
     if (SetSpaceGlyphIfSimple(aFont, aContext, aCharIndex, ' ')) {
         return;
     }
     aFont->InitWordCache();
     static const uint8_t space = ' ';
     gfxShapedWord *sw = aFont->GetShapedWord(aContext,
                                              &space, 1,
                                              HashMix(0, ' '),
                                              MOZ_SCRIPT_LATIN,
                                              mAppUnitsPerDevUnit,
                                              gfxTextRunFactory::TEXT_IS_8BIT |
                                              gfxTextRunFactory::TEXT_IS_ASCII |
                                              gfxTextRunFactory::TEXT_IS_PERSISTENT,
                                              nullptr);
     if (sw) {
         AddGlyphRun(aFont, gfxTextRange::kFontGroup, aCharIndex, false);
         CopyGlyphDataFrom(sw, aCharIndex);
     }
 }
 bool
 gfxTextRun::SetSpaceGlyphIfSimple(gfxFont *aFont, gfxContext *aContext,
                                   uint32_t aCharIndex, char16_t aSpaceChar)
 {
     uint32_t spaceGlyph = aFont->GetSpaceGlyph();
     if (!spaceGlyph || !CompressedGlyph::IsSimpleGlyphID(spaceGlyph)) {
         return false;
     }
     uint32_t spaceWidthAppUnits =
         NS_lroundf(aFont->GetMetrics().spaceWidth * mAppUnitsPerDevUnit);
     if (!CompressedGlyph::IsSimpleAdvance(spaceWidthAppUnits)) {
         return false;
     }
     AddGlyphRun(aFont, gfxTextRange::kFontGroup, aCharIndex, false);
     CompressedGlyph g;
     g.SetSimpleGlyph(spaceWidthAppUnits, spaceGlyph);
     if (aSpaceChar == ' ') {
         g.SetIsSpace();
     }
     GetCharacterGlyphs()[aCharIndex] = g;
     return true;
 }
 void
 gfxTextRun::FetchGlyphExtents(gfxContext *aRefContext)
 {
     bool needsGlyphExtents = NeedsGlyphExtents(this);
     if (!needsGlyphExtents && !mDetailedGlyphs)
         return;
     uint32_t i, runCount = mGlyphRuns.Length();
     CompressedGlyph *charGlyphs = mCharacterGlyphs;
     for (i = 0; i < runCount; ++i) {
         const GlyphRun& run = mGlyphRuns[i];
         gfxFont *font = run.mFont;
         uint32_t start = run.mCharacterOffset;
         uint32_t end = i + 1 < runCount ?
             mGlyphRuns[i + 1].mCharacterOffset : GetLength();
         bool fontIsSetup = false;
         uint32_t j;
         gfxGlyphExtents *extents = font->GetOrCreateGlyphExtents(mAppUnitsPerDevUnit);
         for (j = start; j < end; ++j) {
             const gfxTextRun::CompressedGlyph *glyphData = &charGlyphs[j];
             if (glyphData->IsSimpleGlyph()) {
                 // If we're in speed mode, don't set up glyph extents here; we'll
                 // just return "optimistic" glyph bounds later
                 if (needsGlyphExtents) {
                     uint32_t glyphIndex = glyphData->GetSimpleGlyph();
                     if (!extents->IsGlyphKnown(glyphIndex)) {
                         if (!fontIsSetup) {
                             if (!font->SetupCairoFont(aRefContext)) {
                                 NS_WARNING("failed to set up font for glyph extents");
                                 break;
                             }
                             fontIsSetup = true;
                         }
 #ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
                         ++gGlyphExtentsSetupEagerSimple;
 #endif
                         font->SetupGlyphExtents(aRefContext, glyphIndex, false, extents);
                     }
                 }
             } else if (!glyphData->IsMissing()) {
                 uint32_t glyphCount = glyphData->GetGlyphCount();
                 if (glyphCount == 0) {
                     continue;
                 }
                 const gfxTextRun::DetailedGlyph *details = GetDetailedGlyphs(j);
                 if (!details) {
                     continue;
                 }
                 for (uint32_t k = 0; k < glyphCount; ++k, ++details) {
                     uint32_t glyphIndex = details->mGlyphID;
                     if (!extents->IsGlyphKnownWithTightExtents(glyphIndex)) {
                         if (!fontIsSetup) {
                             if (!font->SetupCairoFont(aRefContext)) {
                                 NS_WARNING("failed to set up font for glyph extents");
                                 break;
                             }
                             fontIsSetup = true;
                         }
 #ifdef DEBUG_TEXT_RUN_STORAGE_METRICS
                         ++gGlyphExtentsSetupEagerTight;
 #endif
                         font->SetupGlyphExtents(aRefContext, glyphIndex, true, extents);
                     }
                 }
             }
         }
     }
 }
 gfxTextRun::ClusterIterator::ClusterIterator(gfxTextRun *aTextRun)
     : mTextRun(aTextRun), mCurrentChar(uint32_t(-1))
 {
 }
 void
 gfxTextRun::ClusterIterator::Reset()
 {
     mCurrentChar = uint32_t(-1);
 }
 bool
 gfxTextRun::ClusterIterator::NextCluster()
 {
     uint32_t len = mTextRun->GetLength();
     while (++mCurrentChar < len) {
         if (mTextRun->IsClusterStart(mCurrentChar)) {
             return true;
         }
     }
     mCurrentChar = uint32_t(-1);
     return false;
 }
 uint32_t
 gfxTextRun::ClusterIterator::ClusterLength() const
 {
     if (mCurrentChar == uint32_t(-1)) {
         return 0;
     }
     uint32_t i = mCurrentChar,
              len = mTextRun->GetLength();
     while (++i < len) {
         if (mTextRun->IsClusterStart(i)) {
             break;
         }
     }
     return i - mCurrentChar;
 }
 gfxFloat
 gfxTextRun::ClusterIterator::ClusterAdvance(PropertyProvider *aProvider) const
 {
     if (mCurrentChar == uint32_t(-1)) {
         return 0;
     }
     return mTextRun->GetAdvanceWidth(mCurrentChar, ClusterLength(), aProvider);
 }
 size_t
 gfxTextRun::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf)
 {
     // The second arg is how much gfxTextRun::AllocateStorage would have
     // allocated.
     size_t total = mGlyphRuns.SizeOfExcludingThis(aMallocSizeOf);
     if (mDetailedGlyphs) {
         total += mDetailedGlyphs->SizeOfIncludingThis(aMallocSizeOf);
     }
     return total;
 }
 size_t
 gfxTextRun::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf)
 {
     return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
 }
 #ifdef DEBUG
 void
 gfxTextRun::Dump(FILE* aOutput) {
     if (!aOutput) {
         aOutput = stdout;
     }
     uint32_t i;
     fputc('[', aOutput);
     for (i = 0; i < mGlyphRuns.Length(); ++i) {
         if (i > 0) {
             fputc(',', aOutput);
         }
         gfxFont* font = mGlyphRuns[i].mFont;
         const gfxFontStyle* style = font->GetStyle();
         NS_ConvertUTF16toUTF8 fontName(font->GetName());
         nsAutoCString lang;
         style->language->ToUTF8String(lang);
         fprintf(aOutput, "%d: %s %f/%d/%d/%s", mGlyphRuns[i].mCharacterOffset,
                 fontName.get(), style->size,
                 style->weight, style->style, lang.get());
     }
     fputc(']', aOutput);
 }
 #endif

The Tor Browser / annotate

gfx/thebes/gfxFont.cpp@97036ab72558 (annotated)

gfx/thebes/gfxFont.cpp