1/* 2 * Copyright © 2007,2008,2009 Red Hat, Inc. 3 * Copyright © 2012 Google, Inc. 4 * 5 * This is part of HarfBuzz, a text shaping library. 6 * 7 * Permission is hereby granted, without written agreement and without 8 * license or royalty fees, to use, copy, modify, and distribute this 9 * software and its documentation for any purpose, provided that the 10 * above copyright notice and the following two paragraphs appear in 11 * all copies of this software. 12 * 13 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR 14 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 15 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN 16 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 17 * DAMAGE. 18 * 19 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, 20 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 21 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 22 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO 23 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 24 * 25 * Red Hat Author(s): Behdad Esfahbod 26 * Google Author(s): Behdad Esfahbod 27 */ 28 29#ifndef HB_OPEN_FILE_PRIVATE_HH 30#define HB_OPEN_FILE_PRIVATE_HH 31 32#include "hb-open-type-private.hh" 33 34 35namespace OT { 36 37 38/* 39 * 40 * The OpenType Font File 41 * 42 */ 43 44 45/* 46 * Organization of an OpenType Font 47 */ 48 49struct OpenTypeFontFile; 50struct OffsetTable; 51struct TTCHeader; 52 53 54typedef struct TableRecord 55{ 56 inline bool sanitize (hb_sanitize_context_t *c) { 57 TRACE_SANITIZE (this); 58 return TRACE_RETURN (c->check_struct (this)); 59 } 60 61 Tag tag; /* 4-byte identifier. */ 62 CheckSum checkSum; /* CheckSum for this table. */ 63 ULONG offset; /* Offset from beginning of TrueType font 64 * file. */ 65 ULONG length; /* Length of this table. */ 66 public: 67 DEFINE_SIZE_STATIC (16); 68} OpenTypeTable; 69 70typedef struct OffsetTable 71{ 72 friend struct OpenTypeFontFile; 73 74 inline unsigned int get_table_count (void) const 75 { return numTables; } 76 inline const TableRecord& get_table (unsigned int i) const 77 { 78 if (unlikely (i >= numTables)) return Null(TableRecord); 79 return tables[i]; 80 } 81 inline bool find_table_index (hb_tag_t tag, unsigned int *table_index) const 82 { 83 Tag t; 84 t.set (tag); 85 unsigned int count = numTables; 86 for (unsigned int i = 0; i < count; i++) 87 { 88 if (t == tables[i].tag) 89 { 90 if (table_index) *table_index = i; 91 return true; 92 } 93 } 94 if (table_index) *table_index = Index::NOT_FOUND_INDEX; 95 return false; 96 } 97 inline const TableRecord& get_table_by_tag (hb_tag_t tag) const 98 { 99 unsigned int table_index; 100 find_table_index (tag, &table_index); 101 return get_table (table_index); 102 } 103 104 public: 105 inline bool sanitize (hb_sanitize_context_t *c) { 106 TRACE_SANITIZE (this); 107 return TRACE_RETURN (c->check_struct (this) && c->check_array (tables, TableRecord::static_size, numTables)); 108 } 109 110 protected: 111 Tag sfnt_version; /* '\0\001\0\00' if TrueType / 'OTTO' if CFF */ 112 USHORT numTables; /* Number of tables. */ 113 USHORT searchRangeZ; /* (Maximum power of 2 <= numTables) x 16 */ 114 USHORT entrySelectorZ; /* Log2(maximum power of 2 <= numTables). */ 115 USHORT rangeShiftZ; /* NumTables x 16-searchRange. */ 116 TableRecord tables[VAR]; /* TableRecord entries. numTables items */ 117 public: 118 DEFINE_SIZE_ARRAY (12, tables); 119} OpenTypeFontFace; 120 121 122/* 123 * TrueType Collections 124 */ 125 126struct TTCHeaderVersion1 127{ 128 friend struct TTCHeader; 129 130 inline unsigned int get_face_count (void) const { return table.len; } 131 inline const OpenTypeFontFace& get_face (unsigned int i) const { return this+table[i]; } 132 133 inline bool sanitize (hb_sanitize_context_t *c) { 134 TRACE_SANITIZE (this); 135 return TRACE_RETURN (table.sanitize (c, this)); 136 } 137 138 protected: 139 Tag ttcTag; /* TrueType Collection ID string: 'ttcf' */ 140 FixedVersion version; /* Version of the TTC Header (1.0), 141 * 0x00010000u */ 142 ArrayOf<OffsetTo<OffsetTable, ULONG>, ULONG> 143 table; /* Array of offsets to the OffsetTable for each font 144 * from the beginning of the file */ 145 public: 146 DEFINE_SIZE_ARRAY (12, table); 147}; 148 149struct TTCHeader 150{ 151 friend struct OpenTypeFontFile; 152 153 private: 154 155 inline unsigned int get_face_count (void) const 156 { 157 switch (u.header.version.major) { 158 case 2: /* version 2 is compatible with version 1 */ 159 case 1: return u.version1.get_face_count (); 160 default:return 0; 161 } 162 } 163 inline const OpenTypeFontFace& get_face (unsigned int i) const 164 { 165 switch (u.header.version.major) { 166 case 2: /* version 2 is compatible with version 1 */ 167 case 1: return u.version1.get_face (i); 168 default:return Null(OpenTypeFontFace); 169 } 170 } 171 172 inline bool sanitize (hb_sanitize_context_t *c) { 173 TRACE_SANITIZE (this); 174 if (unlikely (!u.header.version.sanitize (c))) return TRACE_RETURN (false); 175 switch (u.header.version.major) { 176 case 2: /* version 2 is compatible with version 1 */ 177 case 1: return TRACE_RETURN (u.version1.sanitize (c)); 178 default:return TRACE_RETURN (true); 179 } 180 } 181 182 protected: 183 union { 184 struct { 185 Tag ttcTag; /* TrueType Collection ID string: 'ttcf' */ 186 FixedVersion version; /* Version of the TTC Header (1.0 or 2.0), 187 * 0x00010000u or 0x00020000u */ 188 } header; 189 TTCHeaderVersion1 version1; 190 } u; 191}; 192 193 194/* 195 * OpenType Font File 196 */ 197 198struct OpenTypeFontFile 199{ 200 static const hb_tag_t CFFTag = HB_TAG ('O','T','T','O'); /* OpenType with Postscript outlines */ 201 static const hb_tag_t TrueTypeTag = HB_TAG ( 0 , 1 , 0 , 0 ); /* OpenType with TrueType outlines */ 202 static const hb_tag_t TTCTag = HB_TAG ('t','t','c','f'); /* TrueType Collection */ 203 static const hb_tag_t TrueTag = HB_TAG ('t','r','u','e'); /* Obsolete Apple TrueType */ 204 static const hb_tag_t Typ1Tag = HB_TAG ('t','y','p','1'); /* Obsolete Apple Type1 font in SFNT container */ 205 206 inline hb_tag_t get_tag (void) const { return u.tag; } 207 208 inline unsigned int get_face_count (void) const 209 { 210 switch (u.tag) { 211 case CFFTag: /* All the non-collection tags */ 212 case TrueTag: 213 case Typ1Tag: 214 case TrueTypeTag: return 1; 215 case TTCTag: return u.ttcHeader.get_face_count (); 216 default: return 0; 217 } 218 } 219 inline const OpenTypeFontFace& get_face (unsigned int i) const 220 { 221 switch (u.tag) { 222 /* Note: for non-collection SFNT data we ignore index. This is because 223 * Apple dfont container is a container of SFNT's. So each SFNT is a 224 * non-TTC, but the index is more than zero. */ 225 case CFFTag: /* All the non-collection tags */ 226 case TrueTag: 227 case Typ1Tag: 228 case TrueTypeTag: return u.fontFace; 229 case TTCTag: return u.ttcHeader.get_face (i); 230 default: return Null(OpenTypeFontFace); 231 } 232 } 233 234 inline bool sanitize (hb_sanitize_context_t *c) { 235 TRACE_SANITIZE (this); 236 if (unlikely (!u.tag.sanitize (c))) return TRACE_RETURN (false); 237 switch (u.tag) { 238 case CFFTag: /* All the non-collection tags */ 239 case TrueTag: 240 case Typ1Tag: 241 case TrueTypeTag: return TRACE_RETURN (u.fontFace.sanitize (c)); 242 case TTCTag: return TRACE_RETURN (u.ttcHeader.sanitize (c)); 243 default: return TRACE_RETURN (true); 244 } 245 } 246 247 protected: 248 union { 249 Tag tag; /* 4-byte identifier. */ 250 OpenTypeFontFace fontFace; 251 TTCHeader ttcHeader; 252 } u; 253 public: 254 DEFINE_SIZE_UNION (4, tag); 255}; 256 257 258} /* namespace OT */ 259 260 261#endif /* HB_OPEN_FILE_PRIVATE_HH */ 262