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Diffstat (limited to 'modules/freetype2/include/freetype/ftgxval.h')
-rw-r--r-- | modules/freetype2/include/freetype/ftgxval.h | 354 |
1 files changed, 354 insertions, 0 deletions
diff --git a/modules/freetype2/include/freetype/ftgxval.h b/modules/freetype2/include/freetype/ftgxval.h new file mode 100644 index 0000000000..e8de9a6ed5 --- /dev/null +++ b/modules/freetype2/include/freetype/ftgxval.h @@ -0,0 +1,354 @@ +/**************************************************************************** + * + * ftgxval.h + * + * FreeType API for validating TrueTypeGX/AAT tables (specification). + * + * Copyright (C) 2004-2023 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 <freetype/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 */ |