1 // Copyright 2013 Google Inc. All Rights Reserved. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 // 15 // Data model for a font file in sfnt format, reading and writing functions and 16 // accessors for the glyph data. 17 18 #ifndef WOFF2_FONT_H_ 19 #define WOFF2_FONT_H_ 20 21 #include <stddef.h> 22 #include <inttypes.h> 23 #include <map> 24 #include <vector> 25 26 namespace woff2 { 27 28 // Represents an sfnt font file. Only the table directory is parsed, for the 29 // table data we only store a raw pointer, therefore a font object is valid only 30 // as long the data from which it was parsed is around. 31 struct Font { 32 uint32_t flavor; 33 uint16_t num_tables; 34 35 struct Table { 36 uint32_t tag; 37 uint32_t checksum; 38 uint32_t offset; 39 uint32_t length; 40 const uint8_t* data; 41 42 // Buffer used to mutate the data before writing out. 43 std::vector<uint8_t> buffer; 44 }; 45 std::map<uint32_t, Table> tables; 46 47 Table* FindTable(uint32_t tag); 48 const Table* FindTable(uint32_t tag) const; 49 }; 50 51 // Parses the font from the given data. Returns false on parsing failure or 52 // buffer overflow. The font is valid only so long the input data pointer is 53 // valid. 54 bool ReadFont(const uint8_t* data, size_t len, Font* font); 55 56 // Returns the file size of the font. 57 size_t FontFileSize(const Font& font); 58 59 // Writes the font into the specified dst buffer. The dst_size should be the 60 // same as returned by FontFileSize(). Returns false upon buffer overflow (which 61 // should not happen if dst_size was computed by FontFileSize()). 62 bool WriteFont(const Font& font, uint8_t* dst, size_t dst_size); 63 64 // Returns the number of glyphs in the font. 65 // NOTE: Currently this works only for TrueType-flavored fonts, will return 66 // zero for CFF-flavored fonts. 67 int NumGlyphs(const Font& font); 68 69 // Sets *glyph_data and *glyph_size to point to the location of the glyph data 70 // with the given index. Returns false if the glyph is not found. 71 bool GetGlyphData(const Font& font, int glyph_index, 72 const uint8_t** glyph_data, size_t* glyph_size); 73 74 // Removes the digital signature (DSIG) table 75 bool RemoveDigitalSignature(Font* font); 76 77 } // namespace woff2 78 79 #endif // WOFF2_FONT_H_ 80