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Editing: ftgxval.h
/***************************************************************************/ /* */ /* ftgxval.h */ /* */ /* FreeType API for validating TrueTypeGX/AAT tables (specification). */ /* */ /* Copyright 2004-2018 by */ /* Masatake YAMATO, Redhat K.K, */ /* David Turner, Robert Wilhelm, and Werner Lemberg. */ /* */ /* This file is part of the FreeType project, and may only be used, */ /* modified, and distributed under the terms of the FreeType project */ /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ /* this file you indicate that you have read the license and */ /* understand and accept it fully. */ /* */ /***************************************************************************/ /***************************************************************************/ /* */ /* gxvalid is derived from both gxlayout module and otvalid module. */ /* Development of gxlayout is supported by the Information-technology */ /* Promotion Agency(IPA), Japan. */ /* */ /***************************************************************************/ #ifndef FTGXVAL_H_ #define FTGXVAL_H_ #include <ft2build.h> #include FT_FREETYPE_H #ifdef FREETYPE_H #error "freetype.h of FreeType 1 has been loaded!" #error "Please fix the directory search order for header files" #error "so that freetype.h of FreeType 2 is found first." #endif FT_BEGIN_HEADER /*************************************************************************/ /* */ /* <Section> */ /* gx_validation */ /* */ /* <Title> */ /* TrueTypeGX/AAT Validation */ /* */ /* <Abstract> */ /* An API to validate TrueTypeGX/AAT tables. */ /* */ /* <Description> */ /* This section contains the declaration of functions to validate */ /* some TrueTypeGX tables (feat, mort, morx, bsln, just, kern, opbd, */ /* trak, prop, lcar). */ /* */ /* <Order> */ /* FT_TrueTypeGX_Validate */ /* FT_TrueTypeGX_Free */ /* */ /* FT_ClassicKern_Validate */ /* FT_ClassicKern_Free */ /* */ /* FT_VALIDATE_GX_LENGTH */ /* FT_VALIDATE_GXXXX */ /* FT_VALIDATE_CKERNXXX */ /* */ /*************************************************************************/ /*************************************************************************/ /* */ /* */ /* Warning: Use FT_VALIDATE_XXX to validate a table. */ /* Following definitions are for gxvalid developers. */ /* */ /* */ /*************************************************************************/ #define FT_VALIDATE_feat_INDEX 0 #define FT_VALIDATE_mort_INDEX 1 #define FT_VALIDATE_morx_INDEX 2 #define FT_VALIDATE_bsln_INDEX 3 #define FT_VALIDATE_just_INDEX 4 #define FT_VALIDATE_kern_INDEX 5 #define FT_VALIDATE_opbd_INDEX 6 #define FT_VALIDATE_trak_INDEX 7 #define FT_VALIDATE_prop_INDEX 8 #define FT_VALIDATE_lcar_INDEX 9 #define FT_VALIDATE_GX_LAST_INDEX FT_VALIDATE_lcar_INDEX /************************************************************************* * * @macro: * FT_VALIDATE_GX_LENGTH * * @description: * The number of tables checked in this module. Use it as a parameter * for the `table-length' argument of function @FT_TrueTypeGX_Validate. */ #define FT_VALIDATE_GX_LENGTH ( FT_VALIDATE_GX_LAST_INDEX + 1 ) /* */ /* Up to 0x1000 is used by otvalid. Ox2xxx is reserved for feature OT extension. */ #define FT_VALIDATE_GX_START 0x4000 #define FT_VALIDATE_GX_BITFIELD( tag ) \ ( FT_VALIDATE_GX_START << FT_VALIDATE_##tag##_INDEX ) /********************************************************************** * * @enum: * FT_VALIDATE_GXXXX * * @description: * A list of bit-field constants used with @FT_TrueTypeGX_Validate to * indicate which TrueTypeGX/AAT Type tables should be validated. * * @values: * FT_VALIDATE_feat :: * Validate `feat' table. * * FT_VALIDATE_mort :: * Validate `mort' table. * * FT_VALIDATE_morx :: * Validate `morx' table. * * FT_VALIDATE_bsln :: * Validate `bsln' table. * * FT_VALIDATE_just :: * Validate `just' table. * * FT_VALIDATE_kern :: * Validate `kern' table. * * FT_VALIDATE_opbd :: * Validate `opbd' table. * * FT_VALIDATE_trak :: * Validate `trak' table. * * FT_VALIDATE_prop :: * Validate `prop' table. * * FT_VALIDATE_lcar :: * Validate `lcar' table. * * FT_VALIDATE_GX :: * Validate all TrueTypeGX tables (feat, mort, morx, bsln, just, kern, * opbd, trak, prop and lcar). * */ #define FT_VALIDATE_feat FT_VALIDATE_GX_BITFIELD( feat ) #define FT_VALIDATE_mort FT_VALIDATE_GX_BITFIELD( mort ) #define FT_VALIDATE_morx FT_VALIDATE_GX_BITFIELD( morx ) #define FT_VALIDATE_bsln FT_VALIDATE_GX_BITFIELD( bsln ) #define FT_VALIDATE_just FT_VALIDATE_GX_BITFIELD( just ) #define FT_VALIDATE_kern FT_VALIDATE_GX_BITFIELD( kern ) #define FT_VALIDATE_opbd FT_VALIDATE_GX_BITFIELD( opbd ) #define FT_VALIDATE_trak FT_VALIDATE_GX_BITFIELD( trak ) #define FT_VALIDATE_prop FT_VALIDATE_GX_BITFIELD( prop ) #define FT_VALIDATE_lcar FT_VALIDATE_GX_BITFIELD( lcar ) #define FT_VALIDATE_GX ( FT_VALIDATE_feat | \ FT_VALIDATE_mort | \ FT_VALIDATE_morx | \ FT_VALIDATE_bsln | \ FT_VALIDATE_just | \ FT_VALIDATE_kern | \ FT_VALIDATE_opbd | \ FT_VALIDATE_trak | \ FT_VALIDATE_prop | \ FT_VALIDATE_lcar ) /********************************************************************** * * @function: * FT_TrueTypeGX_Validate * * @description: * Validate various TrueTypeGX tables to assure that all offsets and * indices are valid. The idea is that a higher-level library that * actually does the text layout can access those tables without * error checking (which can be quite time consuming). * * @input: * face :: * A handle to the input face. * * validation_flags :: * A bit field that specifies the tables to be validated. See * @FT_VALIDATE_GXXXX for possible values. * * table_length :: * The size of the `tables' array. Normally, @FT_VALIDATE_GX_LENGTH * should be passed. * * @output: * tables :: * The array where all validated sfnt tables are stored. * The array itself must be allocated by a client. * * @return: * FreeType error code. 0~means success. * * @note: * This function only works with TrueTypeGX fonts, returning an error * otherwise. * * After use, the application should deallocate the buffers pointed to by * each `tables' element, by calling @FT_TrueTypeGX_Free. A NULL value * indicates that the table either doesn't exist in the font, the * application hasn't asked for validation, or the validator doesn't have * the ability to validate the sfnt table. */ FT_EXPORT( FT_Error ) FT_TrueTypeGX_Validate( FT_Face face, FT_UInt validation_flags, FT_Bytes tables[FT_VALIDATE_GX_LENGTH], FT_UInt table_length ); /********************************************************************** * * @function: * FT_TrueTypeGX_Free * * @description: * Free the buffer allocated by TrueTypeGX validator. * * @input: * face :: * A handle to the input face. * * table :: * The pointer to the buffer allocated by * @FT_TrueTypeGX_Validate. * * @note: * This function must be used to free the buffer allocated by * @FT_TrueTypeGX_Validate only. */ FT_EXPORT( void ) FT_TrueTypeGX_Free( FT_Face face, FT_Bytes table ); /********************************************************************** * * @enum: * FT_VALIDATE_CKERNXXX * * @description: * A list of bit-field constants used with @FT_ClassicKern_Validate * to indicate the classic kern dialect or dialects. If the selected * type doesn't fit, @FT_ClassicKern_Validate regards the table as * invalid. * * @values: * FT_VALIDATE_MS :: * Handle the `kern' table as a classic Microsoft kern table. * * FT_VALIDATE_APPLE :: * Handle the `kern' table as a classic Apple kern table. * * FT_VALIDATE_CKERN :: * Handle the `kern' as either classic Apple or Microsoft kern table. */ #define FT_VALIDATE_MS ( FT_VALIDATE_GX_START << 0 ) #define FT_VALIDATE_APPLE ( FT_VALIDATE_GX_START << 1 ) #define FT_VALIDATE_CKERN ( FT_VALIDATE_MS | FT_VALIDATE_APPLE ) /********************************************************************** * * @function: * FT_ClassicKern_Validate * * @description: * Validate classic (16-bit format) kern table to assure that the offsets * and indices are valid. The idea is that a higher-level library that * actually does the text layout can access those tables without error * checking (which can be quite time consuming). * * The `kern' table validator in @FT_TrueTypeGX_Validate deals with both * the new 32-bit format and the classic 16-bit format, while * FT_ClassicKern_Validate only supports the classic 16-bit format. * * @input: * face :: * A handle to the input face. * * validation_flags :: * A bit field that specifies the dialect to be validated. See * @FT_VALIDATE_CKERNXXX for possible values. * * @output: * ckern_table :: * A pointer to the kern table. * * @return: * FreeType error code. 0~means success. * * @note: * After use, the application should deallocate the buffers pointed to by * `ckern_table', by calling @FT_ClassicKern_Free. A NULL value * indicates that the table doesn't exist in the font. */ FT_EXPORT( FT_Error ) FT_ClassicKern_Validate( FT_Face face, FT_UInt validation_flags, FT_Bytes *ckern_table ); /********************************************************************** * * @function: * FT_ClassicKern_Free * * @description: * Free the buffer allocated by classic Kern validator. * * @input: * face :: * A handle to the input face. * * table :: * The pointer to the buffer that is allocated by * @FT_ClassicKern_Validate. * * @note: * This function must be used to free the buffer allocated by * @FT_ClassicKern_Validate only. */ FT_EXPORT( void ) FT_ClassicKern_Free( FT_Face face, FT_Bytes table ); /* */ FT_END_HEADER #endif /* FTGXVAL_H_ */ /* END */
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