Add m-esr52 at 52.6.0

1 files changed, 304 insertions, 0 deletions

diff --git a/layout/generic/nsTextFrameUtils.cpp b/layout/generic/nsTextFrameUtils.cpp
new file mode 100644
index 000000000..d07400f2b
--- /dev/null
+++ b/layout/generic/nsTextFrameUtils.cpp
@@ -0,0 +1,304 @@
+/* -*- 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 "nsBidiUtils.h"
+#include "nsCharTraits.h"
+#include "nsIContent.h"
+#include "nsStyleStruct.h"
+#include "nsTextFragment.h"
+#include "nsUnicharUtils.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 == COMPRESS_NONE_TRANSFORM_TO_SPACE) {
+    // Skip discardables.
+    uint32_t i;
+    for (i = 0; i < aLength; ++i) {
+      char16_t ch = aText[i];
+      if (IsDiscardable(ch, &flags)) {
+        aSkipChars->SkipChar();
+      } else {
+        aSkipChars->KeepChar();
+        if (ch > ' ') {
+          lastCharArabic = IS_ARABIC_CHAR(ch);
+        } else if (aCompression == COMPRESS_NONE_TRANSFORM_TO_SPACE) {
+          if (ch == '\t' || ch == '\n') {
+            ch = ' ';
+            flags |= TEXT_WAS_TRANSFORMED;
+          }
+        } else {
+          // aCompression == COMPRESS_NONE
+          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[i];
+      bool nowInWhitespace;
+      if (ch == ' ' &&
+          (i + 1 >= aLength ||
+           !IsSpaceCombiningSequenceTail(&aText[i + 1], aLength - (i + 1)))) {
+        nowInWhitespace = true;
+      } else if (ch == '\n' && aCompression == COMPRESS_WHITESPACE_NEWLINE) {
+        if ((i > 0 && IS_ZERO_WIDTH_SPACE(aText[i - 1])) ||
+            (i + 1 < aLength && IS_ZERO_WIDTH_SPACE(aText[i + 1]))) {
+          aSkipChars->SkipChar();
+          continue;
+        }
+        uint32_t ucs4before;
+        uint32_t ucs4after;
+        if (i > 1 &&
+            NS_IS_LOW_SURROGATE(aText[i - 1]) &&
+            NS_IS_HIGH_SURROGATE(aText[i - 2])) {
+          ucs4before = SURROGATE_TO_UCS4(aText[i - 2], aText[i - 1]);
+        } else if (i > 0) {
+          ucs4before = aText[i - 1];
+        }
+        if (i + 2 < aLength &&
+            NS_IS_HIGH_SURROGATE(aText[i + 1]) &&
+            NS_IS_LOW_SURROGATE(aText[i + 2])) {
+          ucs4after = SURROGATE_TO_UCS4(aText[i + 1], aText[i + 2]);
+        } else if (i + 1 < aLength) {
+          ucs4after = aText[i + 1];
+        }
+        if (i > 0 && IsSegmentBreakSkipChar(ucs4before) &&
+            i + 1 < aLength && IsSegmentBreakSkipChar(ucs4after)) {
+          // Discard newlines between characters that have F, W, or H
+          // EastAsianWidth property and neither side is Hangul.
+          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 == COMPRESS_NONE_TRANSFORM_TO_SPACE) {
+    // Skip discardables.
+    uint32_t i;
+    for (i = 0; i < aLength; ++i) {
+      uint8_t ch = aText[i];
+      if (IsDiscardable(ch, &flags)) {
+        aSkipChars->SkipChar();
+      } else {
+        aSkipChars->KeepChar();
+        if (aCompression == COMPRESS_NONE_TRANSFORM_TO_SPACE) {
+          if (ch == '\t' || ch == '\n') {
+            ch = ' ';
+            flags |= TEXT_WAS_TRANSFORMED;
+          }
+        } else {
+          // aCompression == COMPRESS_NONE
+          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[i];
+      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;
+}