1 files changed, 153 insertions, 0 deletions
diff --git a/gfx/thebes/gfxSkipChars.cpp b/gfx/thebes/gfxSkipChars.cpp
new file mode 100644
index 000000000..d0fad53e2
--- /dev/null
+++ b/gfx/thebes/gfxSkipChars.cpp
@@ -0,0 +1,153 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * 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"
+
+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);
+}