1 /***************************************************************************/ 2 /* */ 3 /* ftotval.h */ 4 /* */ 5 /* FreeType API for validating OpenType tables (specification). */ 6 /* */ 7 /* Copyright 2004-2007, 2013 by */ 8 /* David Turner, Robert Wilhelm, and Werner Lemberg. */ 9 /* */ 10 /* This file is part of the FreeType project, and may only be used, */ 11 /* modified, and distributed under the terms of the FreeType project */ 12 /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ 13 /* this file you indicate that you have read the license and */ 14 /* understand and accept it fully. */ 15 /* */ 16 /***************************************************************************/ 17 18 19 /***************************************************************************/ 20 /* */ 21 /* */ 22 /* Warning: This module might be moved to a different library in the */ 23 /* future to avoid a tight dependency between FreeType and the */ 24 /* OpenType specification. */ 25 /* */ 26 /* */ 27 /***************************************************************************/ 28 29 30 #ifndef __FTOTVAL_H__ 31 #define __FTOTVAL_H__ 32 33 #include <ft2build.h> 34 #include FT_FREETYPE_H 35 36 #ifdef FREETYPE_H 37 #error "freetype.h of FreeType 1 has been loaded!" 38 #error "Please fix the directory search order for header files" 39 #error "so that freetype.h of FreeType 2 is found first." 40 #endif 41 42 43 FT_BEGIN_HEADER 44 45 46 /*************************************************************************/ 47 /* */ 48 /* <Section> */ 49 /* ot_validation */ 50 /* */ 51 /* <Title> */ 52 /* OpenType Validation */ 53 /* */ 54 /* <Abstract> */ 55 /* An API to validate OpenType tables. */ 56 /* */ 57 /* <Description> */ 58 /* This section contains the declaration of functions to validate */ 59 /* some OpenType tables (BASE, GDEF, GPOS, GSUB, JSTF, MATH). */ 60 /* */ 61 /*************************************************************************/ 62 63 64 /********************************************************************** 65 * 66 * @enum: 67 * FT_VALIDATE_OTXXX 68 * 69 * @description: 70 * A list of bit-field constants used with @FT_OpenType_Validate to 71 * indicate which OpenType tables should be validated. 72 * 73 * @values: 74 * FT_VALIDATE_BASE :: 75 * Validate BASE table. 76 * 77 * FT_VALIDATE_GDEF :: 78 * Validate GDEF table. 79 * 80 * FT_VALIDATE_GPOS :: 81 * Validate GPOS table. 82 * 83 * FT_VALIDATE_GSUB :: 84 * Validate GSUB table. 85 * 86 * FT_VALIDATE_JSTF :: 87 * Validate JSTF table. 88 * 89 * FT_VALIDATE_MATH :: 90 * Validate MATH table. 91 * 92 * FT_VALIDATE_OT :: 93 * Validate all OpenType tables (BASE, GDEF, GPOS, GSUB, JSTF, MATH). 94 * 95 */ 96 #define FT_VALIDATE_BASE 0x0100 97 #define FT_VALIDATE_GDEF 0x0200 98 #define FT_VALIDATE_GPOS 0x0400 99 #define FT_VALIDATE_GSUB 0x0800 100 #define FT_VALIDATE_JSTF 0x1000 101 #define FT_VALIDATE_MATH 0x2000 102 103 #define FT_VALIDATE_OT FT_VALIDATE_BASE | \ 104 FT_VALIDATE_GDEF | \ 105 FT_VALIDATE_GPOS | \ 106 FT_VALIDATE_GSUB | \ 107 FT_VALIDATE_JSTF | \ 108 FT_VALIDATE_MATH 109 110 /* */ 111 112 /********************************************************************** 113 * 114 * @function: 115 * FT_OpenType_Validate 116 * 117 * @description: 118 * Validate various OpenType tables to assure that all offsets and 119 * indices are valid. The idea is that a higher-level library that 120 * actually does the text layout can access those tables without 121 * error checking (which can be quite time consuming). 122 * 123 * @input: 124 * face :: 125 * A handle to the input face. 126 * 127 * validation_flags :: 128 * A bit field that specifies the tables to be validated. See 129 * @FT_VALIDATE_OTXXX for possible values. 130 * 131 * @output: 132 * BASE_table :: 133 * A pointer to the BASE table. 134 * 135 * GDEF_table :: 136 * A pointer to the GDEF table. 137 * 138 * GPOS_table :: 139 * A pointer to the GPOS table. 140 * 141 * GSUB_table :: 142 * A pointer to the GSUB table. 143 * 144 * JSTF_table :: 145 * A pointer to the JSTF table. 146 * 147 * @return: 148 * FreeType error code. 0~means success. 149 * 150 * @note: 151 * This function only works with OpenType fonts, returning an error 152 * otherwise. 153 * 154 * After use, the application should deallocate the five tables with 155 * @FT_OpenType_Free. A NULL value indicates that the table either 156 * doesn't exist in the font, or the application hasn't asked for 157 * validation. 158 */ 159 FT_EXPORT( FT_Error ) 160 FT_OpenType_Validate( FT_Face face, 161 FT_UInt validation_flags, 162 FT_Bytes *BASE_table, 163 FT_Bytes *GDEF_table, 164 FT_Bytes *GPOS_table, 165 FT_Bytes *GSUB_table, 166 FT_Bytes *JSTF_table ); 167 168 /* */ 169 170 /********************************************************************** 171 * 172 * @function: 173 * FT_OpenType_Free 174 * 175 * @description: 176 * Free the buffer allocated by OpenType validator. 177 * 178 * @input: 179 * face :: 180 * A handle to the input face. 181 * 182 * table :: 183 * The pointer to the buffer that is allocated by 184 * @FT_OpenType_Validate. 185 * 186 * @note: 187 * This function must be used to free the buffer allocated by 188 * @FT_OpenType_Validate only. 189 */ 190 FT_EXPORT( void ) 191 FT_OpenType_Free( FT_Face face, 192 FT_Bytes table ); 193 194 195 /* */ 196 197 198 FT_END_HEADER 199 200 #endif /* __FTOTVAL_H__ */ 201 202 203 /* END */ 204
