1 files changed, 146 insertions, 0 deletions
diff --git a/gfx/thebes/gfxSkipChars.cpp b/gfx/thebes/gfxSkipChars.cpp
new file mode 100644
index 0000000000..cd230efe74
--- /dev/null
+++ b/gfx/thebes/gfxSkipChars.cpp
@@ -0,0 +1,146 @@
+/* -*- Mode: C++; tab-width: 20; 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 "gfxSkipChars.h"
+#include "mozilla/BinarySearch.h"
+#include "mozilla/gfx/Logging.h"
+
+struct SkippedRangeStartComparator {
+  const uint32_t mOffset;
+  explicit SkippedRangeStartComparator(const uint32_t aOffset)
+      : mOffset(aOffset) {}
+  int operator()(const gfxSkipChars::SkippedRange& aRange) const {
+    return (mOffset < aRange.Start()) ? -1 : 1;
+  }
+};
+
+void gfxSkipCharsIterator::SetOriginalOffset(int32_t aOffset) {
+  aOffset += mOriginalStringToSkipCharsOffset;
+  if (MOZ_UNLIKELY(uint32_t(aOffset) > mSkipChars->mCharCount)) {
+    gfxCriticalError() << "invalid offset " << aOffset
+                       << " for gfxSkipChars length " << mSkipChars->mCharCount;
+    aOffset = mSkipChars->mCharCount;
+  }
+
+  mOriginalStringOffset = aOffset;
+
+  const uint32_t rangeCount = mSkipChars->mRanges.Length();
+  if (rangeCount == 0) {
+    mSkippedStringOffset = aOffset;
+    return;
+  }
+
+  // at start of string?
+  if (aOffset == 0) {
+    mSkippedStringOffset = 0;
+    mCurrentRangeIndex =
+        rangeCount && mSkipChars->mRanges[0].Start() == 0 ? 0 : -1;
+    return;
+  }
+
+  // find the range that includes or precedes aOffset
+  const nsTArray<gfxSkipChars::SkippedRange>& ranges = mSkipChars->mRanges;
+  size_t idx;
+  mozilla::BinarySearchIf(ranges, 0, rangeCount,
+                          SkippedRangeStartComparator(aOffset), &idx);
+
+  if (idx == rangeCount) {
+    mCurrentRangeIndex = rangeCount - 1;
+  } else if (uint32_t(aOffset) < ranges[idx].Start()) {
+    mCurrentRangeIndex = idx - 1;
+    if (mCurrentRangeIndex == -1) {
+      mSkippedStringOffset = aOffset;
+      return;
+    }
+  } else {
+    mCurrentRangeIndex = idx;
+  }
+
+  const gfxSkipChars::SkippedRange& r = ranges[mCurrentRangeIndex];
+  if (uint32_t(aOffset) < r.End()) {
+    mSkippedStringOffset = r.SkippedOffset();
+    return;
+  }
+
+  mSkippedStringOffset = aOffset - r.NextDelta();
+}
+
+struct SkippedRangeOffsetComparator {
+  const uint32_t mOffset;
+  explicit SkippedRangeOffsetComparator(const uint32_t aOffset)
+      : mOffset(aOffset) {}
+  int operator()(const gfxSkipChars::SkippedRange& aRange) const {
+    return (mOffset < aRange.SkippedOffset()) ? -1 : 1;
+  }
+};
+
+void gfxSkipCharsIterator::SetSkippedOffset(uint32_t aOffset) {
+  NS_ASSERTION(
+      (mSkipChars->mRanges.IsEmpty() && aOffset <= mSkipChars->mCharCount) ||
+          (aOffset <= mSkipChars->LastRange().SkippedOffset() +
+                          mSkipChars->mCharCount -
+                          mSkipChars->LastRange().End()),
+      "Invalid skipped offset");
+  mSkippedStringOffset = aOffset;
+
+  uint32_t rangeCount = mSkipChars->mRanges.Length();
+  if (rangeCount == 0) {
+    mOriginalStringOffset = aOffset;
+    return;
+  }
+
+  const nsTArray<gfxSkipChars::SkippedRange>& ranges = mSkipChars->mRanges;
+  size_t idx;
+  mozilla::BinarySearchIf(ranges, 0, rangeCount,
+                          SkippedRangeOffsetComparator(aOffset), &idx);
+
+  if (idx == rangeCount) {
+    mCurrentRangeIndex = rangeCount - 1;
+  } else if (aOffset < ranges[idx].SkippedOffset()) {
+    mCurrentRangeIndex = idx - 1;
+    if (mCurrentRangeIndex == -1) {
+      mOriginalStringOffset = aOffset;
+      return;
+    }
+  } else {
+    mCurrentRangeIndex = idx;
+  }
+
+  const gfxSkipChars::SkippedRange& r = ranges[mCurrentRangeIndex];
+  mOriginalStringOffset = r.End() + aOffset - r.SkippedOffset();
+}
+
+bool gfxSkipCharsIterator::IsOriginalCharSkipped(int32_t* aRunLength) const {
+  if (mCurrentRangeIndex == -1) {
+    // we're before the first skipped range (if any)
+    if (aRunLength) {
+      uint32_t end = mSkipChars->mRanges.IsEmpty()
+                         ? mSkipChars->mCharCount
+                         : mSkipChars->mRanges[0].Start();
+      *aRunLength = end - mOriginalStringOffset;
+    }
+    return mSkipChars->mCharCount == uint32_t(mOriginalStringOffset);
+  }
+
+  const gfxSkipChars::SkippedRange& range =
+      mSkipChars->mRanges[mCurrentRangeIndex];
+
+  if (uint32_t(mOriginalStringOffset) < range.End()) {
+    if (aRunLength) {
+      *aRunLength = range.End() - mOriginalStringOffset;
+    }
+    return true;
+  }
+
+  if (aRunLength) {
+    uint32_t end =
+        uint32_t(mCurrentRangeIndex) + 1 < mSkipChars->mRanges.Length()
+            ? mSkipChars->mRanges[mCurrentRangeIndex + 1].Start()
+            : mSkipChars->mCharCount;
+    *aRunLength = end - mOriginalStringOffset;
+  }
+
+  return mSkipChars->mCharCount == uint32_t(mOriginalStringOffset);
+}