1 /* 2 * Copyright (C) 2012 Koji Ishii <kojiishi (at) gmail.com> 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 15 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 16 * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY 17 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 18 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 19 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 20 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 22 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 23 */ 24 25 #ifndef OpenTypeTypes_h 26 #define OpenTypeTypes_h 27 28 #include "platform/SharedBuffer.h" 29 #include "wtf/ByteOrder.h" 30 31 namespace blink { 32 namespace OpenType { 33 34 struct Int16 { 35 Int16(int16_t u) : v(htons(static_cast<uint16_t>(u))) { } 36 operator int16_t() const { return static_cast<int16_t>(ntohs(v)); } 37 uint16_t v; // in BigEndian 38 }; 39 40 struct UInt16 { 41 UInt16(uint16_t u) : v(htons(u)) { } 42 operator uint16_t() const { return ntohs(v); } 43 uint16_t v; // in BigEndian 44 }; 45 46 struct Int32 { 47 Int32(int32_t u) : v(htonl(static_cast<uint32_t>(u))) { } 48 operator int32_t() const { return static_cast<int32_t>(ntohl(v)); } 49 uint32_t v; // in BigEndian 50 }; 51 52 struct UInt32 { 53 UInt32(uint32_t u) : v(htonl(u)) { } 54 operator uint32_t() const { return ntohl(v); } 55 uint32_t v; // in BigEndian 56 }; 57 58 typedef UInt32 Fixed; 59 typedef UInt16 Offset; 60 typedef UInt16 GlyphID; 61 62 // OTTag is native because it's only compared against constants, so we don't 63 // do endian conversion here but make sure constants are in big-endian order. 64 // Note that multi-character literal is implementation-defined in C++0x. 65 typedef uint32_t Tag; 66 #define OT_MAKE_TAG(ch1, ch2, ch3, ch4) ((((uint32_t)(ch4)) << 24) | (((uint32_t)(ch3)) << 16) | (((uint32_t)(ch2)) << 8) | ((uint32_t)(ch1))) 67 68 template <typename T> static const T* validateTable(const RefPtr<SharedBuffer>& buffer, size_t count = 1) 69 { 70 if (!buffer || buffer->size() < sizeof(T) * count) 71 return 0; 72 return reinterpret_cast<const T*>(buffer->data()); 73 } 74 75 struct TableBase { 76 protected: 77 static bool isValidEnd(const SharedBuffer& buffer, const void* position) 78 { 79 if (position < buffer.data()) 80 return false; 81 size_t offset = reinterpret_cast<const char*>(position) - buffer.data(); 82 return offset <= buffer.size(); // "<=" because end is included as valid 83 } 84 85 template <typename T> static const T* validatePtr(const SharedBuffer& buffer, const void* position) 86 { 87 const T* casted = reinterpret_cast<const T*>(position); 88 if (!isValidEnd(buffer, &casted[1])) 89 return 0; 90 return casted; 91 } 92 93 template <typename T> const T* validateOffset(const SharedBuffer& buffer, uint16_t offset) const 94 { 95 return validatePtr<T>(buffer, reinterpret_cast<const int8_t*>(this) + offset); 96 } 97 }; 98 99 } // namespace OpenType 100 } // namespace blink 101 #endif // OpenTypeTypes_h 102
