The Tor Browser: gfx/thebes/gfxSVGGlyphs.h@97036ab72558

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.

     1 /* This Source Code Form is subject to the terms of the Mozilla Public

     2  * License, v. 2.0. If a copy of the MPL was not distributed with this

     3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

     5 #ifndef GFX_SVG_GLYPHS_WRAPPER_H

     6 #define GFX_SVG_GLYPHS_WRAPPER_H

     8 #include "gfxFontUtils.h"

     9 #include "nsString.h"

    10 #include "nsAutoPtr.h"

    11 #include "nsClassHashtable.h"

    12 #include "nsBaseHashtable.h"

    13 #include "nsHashKeys.h"

    14 #include "gfxPattern.h"

    15 #include "mozilla/gfx/UserData.h"

    16 #include "nsRefreshDriver.h"

    17 #include "DrawMode.h"

    19 class nsIDocument;

    20 class nsIContentViewer;

    21 class nsIPresShell;

    22 class gfxSVGGlyphs;

    23 class gfxTextContextPaint;

    25 namespace mozilla {

    26 namespace dom {

    27 class Element;

    28 }

    29 }

    31 /**

    32  * Wraps an SVG document contained in the SVG table of an OpenType font.

    33  * There may be multiple SVG documents in an SVG table which we lazily parse

    34  *   so we have an instance of this class for every document in the SVG table

    35  *   which contains a glyph ID which has been used

    36  * Finds and looks up elements contained in the SVG document which have glyph

    37  *   mappings to be drawn by gfxSVGGlyphs

    38  */

    39 class gfxSVGGlyphsDocument MOZ_FINAL : public nsAPostRefreshObserver

    40 {

    41     typedef mozilla::dom::Element Element;

    43 public:

    44     gfxSVGGlyphsDocument(const uint8_t *aBuffer, uint32_t aBufLen,

    45                          gfxSVGGlyphs *aSVGGlyphs);

    47     Element *GetGlyphElement(uint32_t aGlyphId);

    49     ~gfxSVGGlyphsDocument();

    51     virtual void DidRefresh() MOZ_OVERRIDE;

    53 private:

    54     nsresult ParseDocument(const uint8_t *aBuffer, uint32_t aBufLen);

    56     nsresult SetupPresentation();

    58     void FindGlyphElements(Element *aElement);

    60     void InsertGlyphId(Element *aGlyphElement);

    62     // Weak so as not to create a cycle. mOwner owns us so this can't dangle.

    63     gfxSVGGlyphs* mOwner;

    64     nsCOMPtr<nsIDocument> mDocument;

    65     nsCOMPtr<nsIContentViewer> mViewer;

    66     nsCOMPtr<nsIPresShell> mPresShell;

    68     nsBaseHashtable<nsUint32HashKey, Element*, Element*> mGlyphIdMap;

    70     nsAutoCString mSVGGlyphsDocumentURI;

    71 };

    73 /**

    74  * Used by |gfxFontEntry| to represent the SVG table of an OpenType font.

    75  * Handles lazy parsing of the SVG documents in the table, looking up SVG glyphs

    76  *   and rendering SVG glyphs.

    77  * Each |gfxFontEntry| owns at most one |gfxSVGGlyphs| instance.

    78  */

    79 class gfxSVGGlyphs

    80 {

    81 private:

    82     typedef mozilla::dom::Element Element;

    84 public:

    85     /**

    86      * @param aSVGTable The SVG table from the OpenType font

    87      *

    88      * The gfxSVGGlyphs object takes over ownership of the blob references

    89      * that are passed in, and will hb_blob_destroy() them when finished;

    90      * the caller should -not- destroy these references.

    91      */

    92     gfxSVGGlyphs(hb_blob_t *aSVGTable, gfxFontEntry *aFontEntry);

    94     /**

    95      * Releases our references to the SVG table and cleans up everything else.

    96      */

    97     ~gfxSVGGlyphs();

    99     /**

   100      * This is called when the refresh driver has ticked.

   101      */

   102     void DidRefresh();

   104     /**

   105      * Find the |gfxSVGGlyphsDocument| containing an SVG glyph for |aGlyphId|.

   106      * If |aGlyphId| does not map to an SVG document, return null.

   107      * If a |gfxSVGGlyphsDocument| has not been created for the document, create one.

   108      */

   109     gfxSVGGlyphsDocument *FindOrCreateGlyphsDocument(uint32_t aGlyphId);

   111     /**

   112      * Return true iff there is an SVG glyph for |aGlyphId|

   113      */

   114     bool HasSVGGlyph(uint32_t aGlyphId);

   116     /**

   117      * Render the SVG glyph for |aGlyphId|

   118      * @param aDrawMode Whether to fill or stroke or both; see DrawMode

   119      * @param aContextPaint Information on text context paints.

   120      *   See |gfxTextContextPaint|.

   121      */

   122     bool RenderGlyph(gfxContext *aContext, uint32_t aGlyphId, DrawMode aDrawMode,

   123                      gfxTextContextPaint *aContextPaint);

   125     /**

   126      * Get the extents for the SVG glyph associated with |aGlyphId|

   127      * @param aSVGToAppSpace The matrix mapping the SVG glyph space to the

   128      *   target context space

   129      */

   130     bool GetGlyphExtents(uint32_t aGlyphId, const gfxMatrix& aSVGToAppSpace,

   131                          gfxRect *aResult);

   133 private:

   134     Element *GetGlyphElement(uint32_t aGlyphId);

   136     nsClassHashtable<nsUint32HashKey, gfxSVGGlyphsDocument> mGlyphDocs;

   137     nsBaseHashtable<nsUint32HashKey, Element*, Element*> mGlyphIdMap;

   139     hb_blob_t *mSVGData;

   140     gfxFontEntry *mFontEntry;

   142     const struct Header {

   143         mozilla::AutoSwap_PRUint16 mVersion;

   144         mozilla::AutoSwap_PRUint32 mDocIndexOffset;

   145         mozilla::AutoSwap_PRUint32 mColorPalettesOffset;

   146     } *mHeader;

   148     struct IndexEntry {

   149         mozilla::AutoSwap_PRUint16 mStartGlyph;

   150         mozilla::AutoSwap_PRUint16 mEndGlyph;

   151         mozilla::AutoSwap_PRUint32 mDocOffset;

   152         mozilla::AutoSwap_PRUint32 mDocLength;

   153     };

   155     const struct DocIndex {

   156       mozilla::AutoSwap_PRUint16 mNumEntries;

   157       IndexEntry mEntries[1]; /* actual length = mNumEntries */

   158     } *mDocIndex;

   160     static int CompareIndexEntries(const void *_a, const void *_b);

   161 };

   163 /**

   164  * Used for trickling down paint information through to SVG glyphs.

   165  */

   166 class gfxTextContextPaint

   167 {

   168 protected:

   169     gfxTextContextPaint() { }

   171 public:

   172     static mozilla::gfx::UserDataKey sUserDataKey;

   174     /*

   175      * Get text context pattern with the specified opacity value.

   176      * This lets us inherit paints and paint opacities (i.e. fill/stroke and

   177      * fill-opacity/stroke-opacity) separately.

   178      */

   179     virtual already_AddRefed<gfxPattern> GetFillPattern(float aOpacity,

   180                                                         const gfxMatrix& aCTM) = 0;

   181     virtual already_AddRefed<gfxPattern> GetStrokePattern(float aOpacity,

   182                                                           const gfxMatrix& aCTM) = 0;

   184     virtual float GetFillOpacity() { return 1.0f; }

   185     virtual float GetStrokeOpacity() { return 1.0f; }

   187     void InitStrokeGeometry(gfxContext *aContext,

   188                             float devUnitsPerSVGUnit);

   190     FallibleTArray<gfxFloat>& GetStrokeDashArray() {

   191         return mDashes;

   192     }

   194     gfxFloat GetStrokeDashOffset() {

   195         return mDashOffset;

   196     }

   198     gfxFloat GetStrokeWidth() {

   199         return mStrokeWidth;

   200     }

   202     already_AddRefed<gfxPattern> GetFillPattern(const gfxMatrix& aCTM) {

   203         return GetFillPattern(GetFillOpacity(), aCTM);

   204     }

   206     already_AddRefed<gfxPattern> GetStrokePattern(const gfxMatrix& aCTM) {

   207         return GetStrokePattern(GetStrokeOpacity(), aCTM);

   208     }

   210     virtual ~gfxTextContextPaint() { }

   212 private:

   213     FallibleTArray<gfxFloat> mDashes;

   214     gfxFloat mDashOffset;

   215     gfxFloat mStrokeWidth;

   216 };

   218 /**

   219  * For passing in patterns where the text context has no separate pattern

   220  * opacity value.

   221  */

   222 class SimpleTextContextPaint : public gfxTextContextPaint

   223 {

   224 private:

   225     static const gfxRGBA sZero;

   227 public:

   228     static gfxMatrix SetupDeviceToPatternMatrix(gfxPattern *aPattern,

   229                                                 const gfxMatrix& aCTM)

   230     {

   231         if (!aPattern) {

   232             return gfxMatrix();

   233         }

   234         gfxMatrix deviceToUser = aCTM;

   235         deviceToUser.Invert();

   236         return deviceToUser * aPattern->GetMatrix();

   237     }

   239     SimpleTextContextPaint(gfxPattern *aFillPattern, gfxPattern *aStrokePattern,

   240                           const gfxMatrix& aCTM) :

   241         mFillPattern(aFillPattern ? aFillPattern : new gfxPattern(sZero)),

   242         mStrokePattern(aStrokePattern ? aStrokePattern : new gfxPattern(sZero))

   243     {

   244         mFillMatrix = SetupDeviceToPatternMatrix(aFillPattern, aCTM);

   245         mStrokeMatrix = SetupDeviceToPatternMatrix(aStrokePattern, aCTM);

   246     }

   248     already_AddRefed<gfxPattern> GetFillPattern(float aOpacity,

   249                                                 const gfxMatrix& aCTM) {

   250         if (mFillPattern) {

   251             mFillPattern->SetMatrix(aCTM * mFillMatrix);

   252         }

   253         nsRefPtr<gfxPattern> fillPattern = mFillPattern;

   254         return fillPattern.forget();

   255     }

   257     already_AddRefed<gfxPattern> GetStrokePattern(float aOpacity,

   258                                                   const gfxMatrix& aCTM) {

   259         if (mStrokePattern) {

   260             mStrokePattern->SetMatrix(aCTM * mStrokeMatrix);

   261         }

   262         nsRefPtr<gfxPattern> strokePattern = mStrokePattern;

   263         return strokePattern.forget();

   264     }

   266     float GetFillOpacity() {

   267         return mFillPattern ? 1.0f : 0.0f;

   268     }

   270     float GetStrokeOpacity() {

   271         return mStrokePattern ? 1.0f : 0.0f;

   272     }

   274 private:

   275     nsRefPtr<gfxPattern> mFillPattern;

   276     nsRefPtr<gfxPattern> mStrokePattern;

   278     // Device space to pattern space transforms

   279     gfxMatrix mFillMatrix;

   280     gfxMatrix mStrokeMatrix;

   281 };

   283 #endif

The Tor Browser / file revision

gfx/thebes/gfxSVGGlyphs.h@97036ab72558

gfx/thebes/gfxSVGGlyphs.h