1 files changed, 251 insertions, 0 deletions
diff --git a/gfx/2d/SFNTData.cpp b/gfx/2d/SFNTData.cpp
new file mode 100644
index 000000000..fd29f6694
--- /dev/null
+++ b/gfx/2d/SFNTData.cpp
@@ -0,0 +1,251 @@
+/* -*- 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/. */
+
+#include "SFNTData.h"
+
+#include <algorithm>
+
+#include "BigEndianInts.h"
+#include "Logging.h"
+#include "mozilla/HashFunctions.h"
+#include "SFNTNameTable.h"
+
+namespace mozilla {
+namespace gfx {
+
+#define TRUETYPE_TAG(a, b, c, d) ((a) << 24 | (b) << 16 | (c) << 8 | (d))
+
+#pragma pack(push, 1)
+
+struct TTCHeader
+{
+  BigEndianUint32 ttcTag;    // Always 'ttcf'
+  BigEndianUint32 version;   // Fixed, 0x00010000
+  BigEndianUint32 numFonts;
+};
+
+struct OffsetTable
+{
+  BigEndianUint32 sfntVersion;   // Fixed, 0x00010000 for version 1.0.
+  BigEndianUint16 numTables;
+  BigEndianUint16 searchRange;   // (Maximum power of 2 <= numTables) x 16.
+  BigEndianUint16 entrySelector; // Log2(maximum power of 2 <= numTables).
+  BigEndianUint16 rangeShift;    // NumTables x 16-searchRange.
+};
+
+struct TableDirEntry
+{
+  BigEndianUint32 tag;      // 4 -byte identifier.
+  BigEndianUint32 checkSum; // CheckSum for this table.
+  BigEndianUint32 offset;   // Offset from beginning of TrueType font file.
+  BigEndianUint32 length;   // Length of this table.
+
+  friend bool operator<(const TableDirEntry& lhs, const uint32_t aTag)
+  {
+    return lhs.tag < aTag;
+  }
+};
+
+#pragma pack(pop)
+
+class SFNTData::Font
+{
+public:
+  Font(const OffsetTable *aOffsetTable, const uint8_t *aFontData,
+       uint32_t aDataLength)
+    : mFontData(aFontData)
+    , mFirstDirEntry(reinterpret_cast<const TableDirEntry*>(aOffsetTable + 1))
+    , mEndOfDirEntries(mFirstDirEntry + aOffsetTable->numTables)
+    , mDataLength(aDataLength)
+  {
+  }
+
+  bool GetU16FullName(mozilla::u16string& aU16FullName)
+  {
+    const TableDirEntry* dirEntry =
+      GetDirEntry(TRUETYPE_TAG('n', 'a', 'm', 'e'));
+    if (!dirEntry) {
+      gfxWarning() << "Name table entry not found.";
+      return false;
+    }
+
+    UniquePtr<SFNTNameTable> nameTable =
+      SFNTNameTable::Create((mFontData + dirEntry->offset), dirEntry->length);
+    if (!nameTable) {
+      return false;
+    }
+
+    return nameTable->GetU16FullName(aU16FullName);
+  }
+
+private:
+
+  const TableDirEntry*
+  GetDirEntry(const uint32_t aTag)
+  {
+    const TableDirEntry* foundDirEntry =
+      std::lower_bound(mFirstDirEntry, mEndOfDirEntries, aTag);
+
+    if (foundDirEntry == mEndOfDirEntries || foundDirEntry->tag != aTag) {
+      gfxWarning() << "Font data does not contain tag.";
+      return nullptr;
+    }
+
+    if (mDataLength < (foundDirEntry->offset + foundDirEntry->length)) {
+      gfxWarning() << "Font data too short to contain table.";
+      return nullptr;
+    }
+
+    return foundDirEntry;
+  }
+
+  const uint8_t *mFontData;
+  const TableDirEntry *mFirstDirEntry;
+  const TableDirEntry *mEndOfDirEntries;
+  uint32_t mDataLength;
+};
+
+/* static */
+UniquePtr<SFNTData>
+SFNTData::Create(const uint8_t *aFontData, uint32_t aDataLength)
+{
+  MOZ_ASSERT(aFontData);
+
+  // Check to see if this is a font collection.
+  if (aDataLength < sizeof(TTCHeader)) {
+    gfxWarning() << "Font data too short.";
+    return nullptr;
+  }
+
+  const TTCHeader *ttcHeader = reinterpret_cast<const TTCHeader*>(aFontData);
+  if (ttcHeader->ttcTag == TRUETYPE_TAG('t', 't', 'c', 'f')) {
+    uint32_t numFonts = ttcHeader->numFonts;
+    if (aDataLength < sizeof(TTCHeader) + (numFonts * sizeof(BigEndianUint32))) {
+      gfxWarning() << "Font data too short to contain full TTC Header.";
+      return nullptr;
+    }
+
+    UniquePtr<SFNTData> sfntData(new SFNTData);
+    const BigEndianUint32* offset =
+      reinterpret_cast<const BigEndianUint32*>(aFontData + sizeof(TTCHeader));
+    const BigEndianUint32* endOfOffsets = offset + numFonts;
+    while (offset != endOfOffsets) {
+      if (!sfntData->AddFont(aFontData, aDataLength, *offset)) {
+        return nullptr;
+      }
+      ++offset;
+    }
+
+    return Move(sfntData);
+  }
+
+  UniquePtr<SFNTData> sfntData(new SFNTData);
+  if (!sfntData->AddFont(aFontData, aDataLength, 0)) {
+    return nullptr;
+  }
+
+  return Move(sfntData);
+}
+
+/* static */
+uint64_t
+SFNTData::GetUniqueKey(const uint8_t *aFontData, uint32_t aDataLength)
+{
+  uint64_t hash;
+  UniquePtr<SFNTData> sfntData = SFNTData::Create(aFontData, aDataLength);
+  mozilla::u16string firstName;
+  if (sfntData && sfntData->GetU16FullName(0, firstName)) {
+    hash = HashString(firstName.c_str(), firstName.length());
+  } else {
+    gfxWarning() << "Failed to get name from font data hashing whole font.";
+    hash = HashString(aFontData, aDataLength);
+  }
+
+  return hash << 32 | aDataLength;;
+}
+
+SFNTData::~SFNTData()
+{
+  for (size_t i = 0; i < mFonts.length(); ++i) {
+    delete mFonts[i];
+  }
+}
+
+bool
+SFNTData::GetU16FullName(uint32_t aIndex, mozilla::u16string& aU16FullName)
+{
+  if (aIndex >= mFonts.length()) {
+    gfxWarning() << "aIndex to font data too high.";
+    return false;
+  }
+
+  return mFonts[aIndex]->GetU16FullName(aU16FullName);
+}
+
+bool
+SFNTData::GetU16FullNames(Vector<mozilla::u16string>& aU16FullNames)
+{
+  bool fontFound = false;
+  for (size_t i = 0; i < mFonts.length(); ++i) {
+    mozilla::u16string name;
+    if (mFonts[i]->GetU16FullName(name)) {
+      fontFound = true;
+    }
+    if (!aU16FullNames.append(Move(name))) {
+      return false;
+    }
+  }
+
+  return fontFound;
+}
+
+bool
+SFNTData::GetIndexForU16Name(const mozilla::u16string& aU16FullName,
+                             uint32_t* aIndex, size_t aTruncatedLen)
+{
+  for (size_t i = 0; i < mFonts.length(); ++i) {
+    mozilla::u16string name;
+    if (!mFonts[i]->GetU16FullName(name)) {
+      continue;
+    }
+
+    if (aTruncatedLen) {
+      MOZ_ASSERT(aU16FullName.length() <= aTruncatedLen);
+      name = name.substr(0, aTruncatedLen);
+    }
+
+    if (name == aU16FullName) {
+      *aIndex = i;
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool
+SFNTData::AddFont(const uint8_t *aFontData, uint32_t aDataLength,
+                  uint32_t aOffset)
+{
+  uint32_t remainingLength = aDataLength - aOffset;
+  if (remainingLength < sizeof(OffsetTable)) {
+    gfxWarning() << "Font data too short to contain OffsetTable " << aOffset;
+    return false;
+  }
+
+  const OffsetTable *offsetTable =
+    reinterpret_cast<const OffsetTable*>(aFontData + aOffset);
+  if (remainingLength <
+      sizeof(OffsetTable) + (offsetTable->numTables * sizeof(TableDirEntry))) {
+    gfxWarning() << "Font data too short to contain tables.";
+    return false;
+  }
+
+  return mFonts.append(new Font(offsetTable, aFontData, aDataLength));
+}
+
+} // gfx
+} // mozilla