The Tor Browser: layout/generic/nsTextFrameUtils.cpp@b8a032363ba2 (annotated)

layout/generic/nsTextFrameUtils.cpp@b8a032363ba2 (annotated)

layout/generic/nsTextFrameUtils.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
  * 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 "nsTextFrameUtils.h"
 #include "nsUnicharUtils.h"
 #include "nsBidiUtils.h"
 #include "nsIContent.h"
 #include "nsStyleStruct.h"
 #include "nsTextFragment.h"
 #include <algorithm>
 static bool IsDiscardable(char16_t ch, uint32_t* aFlags)
 {
   // Unlike IS_DISCARDABLE, we don't discard \r. \r will be ignored by gfxTextRun
   // and discarding it would force us to copy text in many cases of preformatted
   // text containing \r\n.
   if (ch == CH_SHY) {
     *aFlags |= nsTextFrameUtils::TEXT_HAS_SHY;
     return true;
   }
   return IsBidiControl(ch);
 }
 static bool IsDiscardable(uint8_t ch, uint32_t* aFlags)
 {
   if (ch == CH_SHY) {
     *aFlags |= nsTextFrameUtils::TEXT_HAS_SHY;
     return true;
   }
   return false;
 }
 char16_t*
 nsTextFrameUtils::TransformText(const char16_t* aText, uint32_t aLength,
                                 char16_t* aOutput,
                                 CompressionMode aCompression,
                                 uint8_t* aIncomingFlags,
                                 gfxSkipChars* aSkipChars,
                                 uint32_t* aAnalysisFlags)
 {
   uint32_t flags = 0;
   char16_t* outputStart = aOutput;
   bool lastCharArabic = false;
   if (aCompression == COMPRESS_NONE ||
       aCompression == DISCARD_NEWLINE) {
     // Skip discardables.
     uint32_t i;
     for (i = 0; i < aLength; ++i) {
       char16_t ch = *aText++;
       if (IsDiscardable(ch, &flags) ||
           (ch == '\n' && aCompression == DISCARD_NEWLINE)) {
         aSkipChars->SkipChar();
       } else {
         aSkipChars->KeepChar();
         if (ch > ' ') {
           lastCharArabic = IS_ARABIC_CHAR(ch);
         } else if (ch == '\t') {
           flags |= TEXT_HAS_TAB;
         }
         *aOutput++ = ch;
       }
     }
     if (lastCharArabic) {
       *aIncomingFlags |= INCOMING_ARABICCHAR;
     } else {
       *aIncomingFlags &= ~INCOMING_ARABICCHAR;
     }
     *aIncomingFlags &= ~INCOMING_WHITESPACE;
   } else {
     bool inWhitespace = (*aIncomingFlags & INCOMING_WHITESPACE) != 0;
     uint32_t i;
     for (i = 0; i < aLength; ++i) {
       char16_t ch = *aText++;
       bool nowInWhitespace;
       if (ch == ' ' &&
           (i + 1 >= aLength ||
            !IsSpaceCombiningSequenceTail(aText, aLength - (i + 1)))) {
         nowInWhitespace = true;
       } else if (ch == '\n' && aCompression == COMPRESS_WHITESPACE_NEWLINE) {
         if (i > 0 && IS_CJ_CHAR(aText[-1]) &&
             i + 1 < aLength && IS_CJ_CHAR(aText[1])) {
           // Discard newlines between CJK chars.
           // XXX this really requires more context to get right!
           aSkipChars->SkipChar();
           continue;
         }
         nowInWhitespace = true;
       } else {
         nowInWhitespace = ch == '\t';
       }
       if (!nowInWhitespace) {
         if (IsDiscardable(ch, &flags)) {
           aSkipChars->SkipChar();
           nowInWhitespace = inWhitespace;
         } else {
           *aOutput++ = ch;
           aSkipChars->KeepChar();
           lastCharArabic = IS_ARABIC_CHAR(ch);
         }
       } else {
         if (inWhitespace) {
           aSkipChars->SkipChar();
         } else {
           if (ch != ' ') {
             flags |= TEXT_WAS_TRANSFORMED;
           }
           *aOutput++ = ' ';
           aSkipChars->KeepChar();
         }
       }
       inWhitespace = nowInWhitespace;
     }
     if (lastCharArabic) {
       *aIncomingFlags |= INCOMING_ARABICCHAR;
     } else {
       *aIncomingFlags &= ~INCOMING_ARABICCHAR;
     }
     if (inWhitespace) {
       *aIncomingFlags |= INCOMING_WHITESPACE;
     } else {
       *aIncomingFlags &= ~INCOMING_WHITESPACE;
     }
   }
   if (outputStart + aLength != aOutput) {
     flags |= TEXT_WAS_TRANSFORMED;
   }
   *aAnalysisFlags = flags;
   return aOutput;
 }
 uint8_t*
 nsTextFrameUtils::TransformText(const uint8_t* aText, uint32_t aLength,
                                 uint8_t* aOutput,
                                 CompressionMode aCompression,
                                 uint8_t* aIncomingFlags,
                                 gfxSkipChars* aSkipChars,
                                 uint32_t* aAnalysisFlags)
 {
   uint32_t flags = 0;
   uint8_t* outputStart = aOutput;
   if (aCompression == COMPRESS_NONE ||
       aCompression == DISCARD_NEWLINE) {
     // Skip discardables.
     uint32_t i;
     for (i = 0; i < aLength; ++i) {
       uint8_t ch = *aText++;
       if (IsDiscardable(ch, &flags) ||
           (ch == '\n' && aCompression == DISCARD_NEWLINE)) {
         aSkipChars->SkipChar();
       } else {
         aSkipChars->KeepChar();
         if (ch == '\t') {
           flags |= TEXT_HAS_TAB;
         }
         *aOutput++ = ch;
       }
     }
     *aIncomingFlags &= ~(INCOMING_ARABICCHAR | INCOMING_WHITESPACE);
   } else {
     bool inWhitespace = (*aIncomingFlags & INCOMING_WHITESPACE) != 0;
     uint32_t i;
     for (i = 0; i < aLength; ++i) {
       uint8_t ch = *aText++;
       bool nowInWhitespace = ch == ' ' || ch == '\t' ||
         (ch == '\n' && aCompression == COMPRESS_WHITESPACE_NEWLINE);
       if (!nowInWhitespace) {
         if (IsDiscardable(ch, &flags)) {
           aSkipChars->SkipChar();
           nowInWhitespace = inWhitespace;
         } else {
           *aOutput++ = ch;
           aSkipChars->KeepChar();
         }
       } else {
         if (inWhitespace) {
           aSkipChars->SkipChar();
         } else {
           if (ch != ' ') {
             flags |= TEXT_WAS_TRANSFORMED;
           }
           *aOutput++ = ' ';
           aSkipChars->KeepChar();
         }
       }
       inWhitespace = nowInWhitespace;
     }
     *aIncomingFlags &= ~INCOMING_ARABICCHAR;
     if (inWhitespace) {
       *aIncomingFlags |= INCOMING_WHITESPACE;
     } else {
       *aIncomingFlags &= ~INCOMING_WHITESPACE;
     }
   }
   if (outputStart + aLength != aOutput) {
     flags |= TEXT_WAS_TRANSFORMED;
   }
   *aAnalysisFlags = flags;
   return aOutput;
 }
 uint32_t
 nsTextFrameUtils::ComputeApproximateLengthWithWhitespaceCompression(
                     nsIContent *aContent, const nsStyleText *aStyleText)
 {
   const nsTextFragment *frag = aContent->GetText();
   // This is an approximation so we don't really need anything
   // too fancy here.
   uint32_t len;
   if (aStyleText->WhiteSpaceIsSignificant()) {
     len = frag->GetLength();
   } else {
     bool is2b = frag->Is2b();
     union {
       const char *s1b;
       const char16_t *s2b;
     } u;
     if (is2b) {
       u.s2b = frag->Get2b();
     } else {
       u.s1b = frag->Get1b();
     }
     bool prevWS = true; // more important to ignore blocks with
                         // only whitespace than get inline boundaries
                         // exactly right
     len = 0;
     for (uint32_t i = 0, i_end = frag->GetLength(); i < i_end; ++i) {
       char16_t c = is2b ? u.s2b[i] : u.s1b[i];
       if (c == ' ' || c == '\n' || c == '\t' || c == '\r') {
         if (!prevWS) {
           ++len;
         }
         prevWS = true;
       } else {
         ++len;
         prevWS = false;
       }
     }
   }
   return len;
 }
 bool nsSkipCharsRunIterator::NextRun() {
   do {
     if (mRunLength) {
       mIterator.AdvanceOriginal(mRunLength);
       NS_ASSERTION(mRunLength > 0, "No characters in run (initial length too large?)");
       if (!mSkipped || mLengthIncludesSkipped) {
         mRemainingLength -= mRunLength;
       }
     }
     if (!mRemainingLength)
       return false;
     int32_t length;
     mSkipped = mIterator.IsOriginalCharSkipped(&length);
     mRunLength = std::min(length, mRemainingLength);
   } while (!mVisitSkipped && mSkipped);
   return true;
 }

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layout/generic/nsTextFrameUtils.cpp@b8a032363ba2 (annotated)

layout/generic/nsTextFrameUtils.cpp