Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 197 insertions, 0 deletions

diff --git a/layout/generic/nsTextFrameUtils.h b/layout/generic/nsTextFrameUtils.h
new file mode 100644
index 0000000000..5b9edf271e
--- /dev/null
+++ b/layout/generic/nsTextFrameUtils.h
@@ -0,0 +1,197 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef NSTEXTFRAMEUTILS_H_
+#define NSTEXTFRAMEUTILS_H_
+
+#include "gfxSkipChars.h"
+#include "nsBidiUtils.h"
+
+class nsIContent;
+struct nsStyleText;
+
+namespace mozilla {
+namespace dom {
+class Text;
+}
+}  // namespace mozilla
+
+#define BIG_TEXT_NODE_SIZE 4096
+
+#define CH_NBSP 160
+#define CH_SHY 173
+#define CH_CJKSP 12288  // U+3000 IDEOGRAPHIC SPACE (CJK Full-Width Space)
+
+class nsTextFrameUtils {
+ public:
+  // These constants are used as textrun flags for textframe textruns.
+  //
+  // If you add a flag, please add support for it in gfxTextRun::Dump.
+  enum class Flags : uint16_t {
+    // The following flags are set by TransformText
+
+    // the text has at least one untransformed tab character
+    HasTab = 0x01,
+    // the original text has at least one soft hyphen character
+    HasShy = 0x02,
+    // the text has at least one untransformed newline character
+    HasNewline = 0x04,
+
+    // Flag used in textrun construction to *prevent* hiding of fallback text
+    // for pending user-fonts (used for Canvas2d text).
+    DontSkipDrawingForPendingUserFonts = 0x08,
+
+    // The following flags are set by nsTextFrame
+
+    IsSimpleFlow = 0x10,
+    IncomingWhitespace = 0x20,
+    TrailingWhitespace = 0x40,
+    CompressedLeadingWhitespace = 0x80,
+    NoBreaks = 0x100,
+    IsTransformed = 0x200,
+    // This gets set if there's a break opportunity at the end of the textrun.
+    // We normally don't use this break opportunity because the following text
+    // will have a break opportunity at the start, but it's useful for line
+    // layout to know about it in case the following content is not text
+    HasTrailingBreak = 0x400,
+
+    // This is set if the textrun was created for a textframe whose
+    // NS_FRAME_IS_IN_SINGLE_CHAR_MI flag is set.  This occurs if the textframe
+    // belongs to a MathML <mi> element whose embedded text consists of a
+    // single character.
+    IsSingleCharMi = 0x800,
+
+    // This is set if the text run might be observing for glyph changes.
+    MightHaveGlyphChanges = 0x1000,
+
+    // For internal use by the memory reporter when accounting for
+    // storage used by textruns.
+    // Because the reporter may visit each textrun multiple times while
+    // walking the frame trees and textrun cache, it needs to mark
+    // textruns that have been seen so as to avoid multiple-accounting.
+    RunSizeAccounted = 0x2000,
+
+    // The following are defined by gfxTextRunFactory rather than here,
+    // so that it also has access to the _INCOMING and MATH_SCRIPT flags
+    // for shaping purposes.
+    // They live in the gfxShapedText::mFlags field rather than the
+    // gfxTextRun::mFlags2 field.
+    // TEXT_TRAILING_ARABICCHAR
+    // TEXT_INCOMING_ARABICCHAR
+    // TEXT_USE_MATH_SCRIPT
+  };
+
+  // These constants are used in TransformText to represent context information
+  // from previous textruns.
+  enum { INCOMING_NONE = 0, INCOMING_WHITESPACE = 1, INCOMING_ARABICCHAR = 2 };
+
+  /**
+   * Returns true if aChars/aLength are something that make a space
+   * character not be whitespace when they follow the space character
+   * (combining mark or join control, ignoring intervening direction
+   * controls).
+   */
+  static bool IsSpaceCombiningSequenceTail(const char16_t* aChars,
+                                           int32_t aLength);
+  static bool IsSpaceCombiningSequenceTail(const uint8_t* aChars,
+                                           int32_t aLength) {
+    return false;
+  }
+
+  enum CompressionMode {
+    COMPRESS_NONE,
+    COMPRESS_WHITESPACE,
+    COMPRESS_WHITESPACE_NEWLINE,
+    COMPRESS_NONE_TRANSFORM_TO_SPACE
+  };
+
+  /**
+   * Create a text run from a run of Unicode text. The text may have whitespace
+   * compressed. A preformatted tab is sent to the text run as a single space.
+   * (Tab spacing must be performed by textframe later.) Certain other
+   * characters are discarded.
+   *
+   * @param aCompression control what is compressed to a
+   * single space character: no compression, compress spaces (not followed
+   * by combining mark) and tabs, compress those plus newlines, or
+   * no compression except newlines are discarded.
+   * @param aIncomingFlags a flag indicating whether there was whitespace
+   * or an Arabic character preceding this text. We set it to indicate if
+   * there's an Arabic character or whitespace preceding the end of this text.
+   */
+  template <class CharT>
+  static CharT* TransformText(const CharT* aText, uint32_t aLength,
+                              CharT* aOutput, CompressionMode aCompression,
+                              uint8_t* aIncomingFlags, gfxSkipChars* aSkipChars,
+                              nsTextFrameUtils::Flags* aAnalysisFlags);
+
+  /**
+   * Returns whether aChar is a character that nsTextFrameUtils::TransformText
+   * might mark as skipped.  This is used by
+   * SVGTextContentElement::GetNumberOfChars to know whether reflowing frames,
+   * so that we have the results of TransformText, is required, or whether we
+   * can use a fast path instead.
+   */
+  template <class CharT>
+  static bool IsSkippableCharacterForTransformText(CharT aChar);
+
+  static void AppendLineBreakOffset(nsTArray<uint32_t>* aArray,
+                                    uint32_t aOffset) {
+    if (aArray->Length() > 0 && (*aArray)[aArray->Length() - 1] == aOffset) {
+      return;
+    }
+    aArray->AppendElement(aOffset);
+  }
+
+  static uint32_t ComputeApproximateLengthWithWhitespaceCompression(
+      mozilla::dom::Text*, const nsStyleText*);
+  static uint32_t ComputeApproximateLengthWithWhitespaceCompression(
+      const nsAString&, const nsStyleText*);
+};
+
+MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(nsTextFrameUtils::Flags)
+
+class nsSkipCharsRunIterator {
+ public:
+  enum LengthMode {
+    LENGTH_UNSKIPPED_ONLY = false,
+    LENGTH_INCLUDES_SKIPPED = true
+  };
+  nsSkipCharsRunIterator(const gfxSkipCharsIterator& aStart,
+                         LengthMode aLengthIncludesSkipped, uint32_t aLength)
+      : mIterator(aStart),
+        mRemainingLength(aLength),
+        mRunLength(0),
+        mSkipped(false),
+        mVisitSkipped(false),
+        mLengthIncludesSkipped(aLengthIncludesSkipped) {}
+  void SetVisitSkipped() { mVisitSkipped = true; }
+  void SetOriginalOffset(int32_t aOffset) {
+    mIterator.SetOriginalOffset(aOffset);
+  }
+  void SetSkippedOffset(uint32_t aOffset) {
+    mIterator.SetSkippedOffset(aOffset);
+  }
+
+  // guaranteed to return only positive-length runs
+  bool NextRun();
+  bool IsSkipped() const { return mSkipped; }
+  // Always returns something > 0
+  int32_t GetRunLength() const { return mRunLength; }
+  const gfxSkipCharsIterator& GetPos() const { return mIterator; }
+  int32_t GetOriginalOffset() const { return mIterator.GetOriginalOffset(); }
+  uint32_t GetSkippedOffset() const { return mIterator.GetSkippedOffset(); }
+
+ private:
+  gfxSkipCharsIterator mIterator;
+  int32_t mRemainingLength;
+  int32_t mRunLength;
+  bool mSkipped;
+  bool mVisitSkipped;
+  bool mLengthIncludesSkipped;
+};
+
+#endif /*NSTEXTFRAMEUTILS_H_*/