| /* |
| * Copyright (C) 2012 Koji Ishii <kojiishi@gmail.com> |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
| * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY |
| * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON |
| * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
| * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #ifndef OpenTypeTypes_h |
| #define OpenTypeTypes_h |
| |
| #if ENABLE(OPENTYPE_MATH) |
| #include "Glyph.h" |
| #endif |
| |
| #include "SharedBuffer.h" |
| |
| namespace WebCore { |
| namespace OpenType { |
| |
| struct BigEndianShort { |
| operator short() const { return (v & 0x00ff) << 8 | v >> 8; } |
| BigEndianShort(short u) : v((u & 0x00ff) << 8 | u >> 8) { } |
| unsigned short v; |
| }; |
| |
| struct BigEndianUShort { |
| operator unsigned short() const { return (v & 0x00ff) << 8 | v >> 8; } |
| BigEndianUShort(unsigned short u) : v((u & 0x00ff) << 8 | u >> 8) { } |
| unsigned short v; |
| }; |
| |
| struct BigEndianLong { |
| operator int() const { return (v & 0xff) << 24 | (v & 0xff00) << 8 | (v & 0xff0000) >> 8 | v >> 24; } |
| BigEndianLong(int u) : v((u & 0xff) << 24 | (u & 0xff00) << 8 | (u & 0xff0000) >> 8 | u >> 24) { } |
| unsigned v; |
| }; |
| |
| struct BigEndianULong { |
| operator unsigned() const { return (v & 0xff) << 24 | (v & 0xff00) << 8 | (v & 0xff0000) >> 8 | v >> 24; } |
| BigEndianULong(unsigned u) : v((u & 0xff) << 24 | (u & 0xff00) << 8 | (u & 0xff0000) >> 8 | u >> 24) { } |
| unsigned v; |
| }; |
| |
| typedef BigEndianShort Int16; |
| typedef BigEndianUShort UInt16; |
| typedef BigEndianLong Int32; |
| typedef BigEndianULong UInt32; |
| |
| typedef UInt32 Fixed; |
| typedef UInt16 Offset; |
| typedef UInt16 GlyphID; |
| |
| // OTTag is native because it's only compared against constants, so we don't |
| // do endian conversion here but make sure constants are in big-endian order. |
| // Note that multi-character literal is implementation-defined in C++0x. |
| typedef uint32_t Tag; |
| #define OT_MAKE_TAG(ch1, ch2, ch3, ch4) ((((uint32_t)(ch4)) << 24) | (((uint32_t)(ch3)) << 16) | (((uint32_t)(ch2)) << 8) | ((uint32_t)(ch1))) |
| |
| template <typename T> static const T* validateTable(const RefPtr<SharedBuffer>& buffer, size_t count = 1) |
| { |
| if (!buffer || buffer->size() < sizeof(T) * count) |
| return 0; |
| return reinterpret_cast<const T*>(buffer->data()); |
| } |
| |
| struct TableBase { |
| protected: |
| static bool isValidEnd(const SharedBuffer& buffer, const void* position) |
| { |
| if (position < buffer.data()) |
| return false; |
| size_t offset = reinterpret_cast<const char*>(position) - buffer.data(); |
| return offset <= buffer.size(); // "<=" because end is included as valid |
| } |
| |
| template <typename T> static const T* validatePtr(const SharedBuffer& buffer, const void* position) |
| { |
| const T* casted = reinterpret_cast<const T*>(position); |
| if (!isValidEnd(buffer, &casted[1])) |
| return 0; |
| return casted; |
| } |
| |
| template <typename T> const T* validateOffset(const SharedBuffer& buffer, uint16_t offset) const |
| { |
| return validatePtr<T>(buffer, reinterpret_cast<const int8_t*>(this) + offset); |
| } |
| }; |
| |
| #if ENABLE(OPENTYPE_VERTICAL) || ENABLE(OPENTYPE_MATH) |
| struct CoverageTable : TableBase { |
| OpenType::UInt16 coverageFormat; |
| }; |
| |
| struct Coverage1Table : CoverageTable { |
| OpenType::UInt16 glyphCount; |
| OpenType::GlyphID glyphArray[1]; |
| }; |
| |
| struct Coverage2Table : CoverageTable { |
| OpenType::UInt16 rangeCount; |
| struct RangeRecord { |
| OpenType::GlyphID start; |
| OpenType::GlyphID end; |
| OpenType::UInt16 startCoverageIndex; |
| } ranges[1]; |
| }; |
| #endif // ENABLE(OPENTYPE_VERTICAL) || ENABLE(OPENTYPE_MATH) |
| |
| #if ENABLE(OPENTYPE_MATH) |
| struct TableWithCoverage : TableBase { |
| protected: |
| bool getCoverageIndex(const SharedBuffer& buffer, const CoverageTable* coverage, Glyph glyph, uint32_t& coverageIndex) const |
| { |
| switch (coverage->coverageFormat) { |
| case 1: { // Coverage Format 1 |
| const Coverage1Table* coverage1 = validatePtr<Coverage1Table>(buffer, coverage); |
| if (!coverage1) |
| return false; |
| uint16_t glyphCount = coverage1->glyphCount; |
| if (!isValidEnd(buffer, &coverage1->glyphArray[glyphCount])) |
| return false; |
| |
| // We do a binary search on the glyph indexes. |
| uint32_t imin = 0, imax = glyphCount; |
| while (imin < imax) { |
| uint32_t imid = (imin + imax) >> 1; |
| uint16_t glyphMid = coverage1->glyphArray[imid]; |
| if (glyphMid == glyph) { |
| coverageIndex = imid; |
| return true; |
| } |
| if (glyphMid < glyph) |
| imin = imid + 1; |
| else |
| imax = imid; |
| } |
| break; |
| } |
| case 2: { // Coverage Format 2 |
| const Coverage2Table* coverage2 = validatePtr<Coverage2Table>(buffer, coverage); |
| if (!coverage2) |
| return false; |
| uint16_t rangeCount = coverage2->rangeCount; |
| if (!isValidEnd(buffer, &coverage2->ranges[rangeCount])) |
| return false; |
| |
| // We do a binary search on the ranges. |
| uint32_t imin = 0, imax = rangeCount; |
| while (imin < imax) { |
| uint32_t imid = (imin + imax) >> 1; |
| uint16_t rStart = coverage2->ranges[imid].start; |
| uint16_t rEnd = coverage2->ranges[imid].end; |
| if (rEnd < glyph) |
| imin = imid + 1; |
| else if (glyph < rStart) |
| imax = imid; |
| else { |
| coverageIndex = coverage2->ranges[imid].startCoverageIndex + glyph - rStart; |
| return true; |
| } |
| } |
| break; |
| } |
| } |
| return false; |
| } |
| }; |
| #endif |
| |
| } // namespace OpenType |
| } // namespace WebCore |
| #endif // OpenTypeTypes_h |