nuclear@0: /***************************************************************************/ nuclear@0: /* */ nuclear@0: /* ftvalid.h */ nuclear@0: /* */ nuclear@0: /* FreeType validation support (specification). */ nuclear@0: /* */ nuclear@0: /* Copyright 2004 by */ nuclear@0: /* David Turner, Robert Wilhelm, and Werner Lemberg. */ nuclear@0: /* */ nuclear@0: /* This file is part of the FreeType project, and may only be used, */ nuclear@0: /* modified, and distributed under the terms of the FreeType project */ nuclear@0: /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ nuclear@0: /* this file you indicate that you have read the license and */ nuclear@0: /* understand and accept it fully. */ nuclear@0: /* */ nuclear@0: /***************************************************************************/ nuclear@0: nuclear@0: nuclear@0: #ifndef __FTVALID_H__ nuclear@0: #define __FTVALID_H__ nuclear@0: nuclear@0: #include nuclear@0: #include FT_CONFIG_STANDARD_LIBRARY_H /* for ft_setjmp and ft_longjmp */ nuclear@0: nuclear@0: nuclear@0: FT_BEGIN_HEADER nuclear@0: nuclear@0: nuclear@0: /*************************************************************************/ nuclear@0: /*************************************************************************/ nuclear@0: /*************************************************************************/ nuclear@0: /**** ****/ nuclear@0: /**** ****/ nuclear@0: /**** V A L I D A T I O N ****/ nuclear@0: /**** ****/ nuclear@0: /**** ****/ nuclear@0: /*************************************************************************/ nuclear@0: /*************************************************************************/ nuclear@0: /*************************************************************************/ nuclear@0: nuclear@0: /* handle to a validation object */ nuclear@0: typedef struct FT_ValidatorRec_ volatile* FT_Validator; nuclear@0: nuclear@0: nuclear@0: /*************************************************************************/ nuclear@0: /* */ nuclear@0: /* There are three distinct validation levels defined here: */ nuclear@0: /* */ nuclear@0: /* FT_VALIDATE_DEFAULT :: */ nuclear@0: /* A table that passes this validation level can be used reliably by */ nuclear@0: /* FreeType. It generally means that all offsets have been checked to */ nuclear@0: /* prevent out-of-bound reads, that array counts are correct, etc. */ nuclear@0: /* */ nuclear@0: /* FT_VALIDATE_TIGHT :: */ nuclear@0: /* A table that passes this validation level can be used reliably and */ nuclear@0: /* doesn't contain invalid data. For example, a charmap table that */ nuclear@0: /* returns invalid glyph indices will not pass, even though it can */ nuclear@0: /* be used with FreeType in default mode (the library will simply */ nuclear@0: /* return an error later when trying to load the glyph). */ nuclear@0: /* */ nuclear@0: /* It also checks that fields which must be a multiple of 2, 4, or 8, */ nuclear@0: /* don't have incorrect values, etc. */ nuclear@0: /* */ nuclear@0: /* FT_VALIDATE_PARANOID :: */ nuclear@0: /* Only for font debugging. Checks that a table follows the */ nuclear@0: /* specification by 100%. Very few fonts will be able to pass this */ nuclear@0: /* level anyway but it can be useful for certain tools like font */ nuclear@0: /* editors/converters. */ nuclear@0: /* */ nuclear@0: typedef enum FT_ValidationLevel_ nuclear@0: { nuclear@0: FT_VALIDATE_DEFAULT = 0, nuclear@0: FT_VALIDATE_TIGHT, nuclear@0: FT_VALIDATE_PARANOID nuclear@0: nuclear@0: } FT_ValidationLevel; nuclear@0: nuclear@0: nuclear@0: /* validator structure */ nuclear@0: typedef struct FT_ValidatorRec_ nuclear@0: { nuclear@0: const FT_Byte* base; /* address of table in memory */ nuclear@0: const FT_Byte* limit; /* `base' + sizeof(table) in memory */ nuclear@0: FT_ValidationLevel level; /* validation level */ nuclear@0: FT_Error error; /* error returned. 0 means success */ nuclear@0: nuclear@0: ft_jmp_buf jump_buffer; /* used for exception handling */ nuclear@0: nuclear@0: } FT_ValidatorRec; nuclear@0: nuclear@0: nuclear@0: #define FT_VALIDATOR( x ) ((FT_Validator)( x )) nuclear@0: nuclear@0: nuclear@0: FT_BASE( void ) nuclear@0: ft_validator_init( FT_Validator valid, nuclear@0: const FT_Byte* base, nuclear@0: const FT_Byte* limit, nuclear@0: FT_ValidationLevel level ); nuclear@0: nuclear@0: /* Do not use this. It's broken and will cause your validator to crash */ nuclear@0: /* if you run it on an invalid font. */ nuclear@0: FT_BASE( FT_Int ) nuclear@0: ft_validator_run( FT_Validator valid ); nuclear@0: nuclear@0: /* Sets the error field in a validator, then calls `longjmp' to return */ nuclear@0: /* to high-level caller. Using `setjmp/longjmp' avoids many stupid */ nuclear@0: /* error checks within the validation routines. */ nuclear@0: /* */ nuclear@0: FT_BASE( void ) nuclear@0: ft_validator_error( FT_Validator valid, nuclear@0: FT_Error error ); nuclear@0: nuclear@0: nuclear@0: /* Calls ft_validate_error. Assumes that the `valid' local variable */ nuclear@0: /* holds a pointer to the current validator object. */ nuclear@0: /* */ nuclear@0: /* Use preprocessor prescan to pass FT_ERR_PREFIX. */ nuclear@0: /* */ nuclear@0: #define FT_INVALID( _prefix, _error ) FT_INVALID_( _prefix, _error ) nuclear@0: #define FT_INVALID_( _prefix, _error ) \ nuclear@0: ft_validator_error( valid, _prefix ## _error ) nuclear@0: nuclear@0: /* called when a broken table is detected */ nuclear@0: #define FT_INVALID_TOO_SHORT \ nuclear@0: FT_INVALID( FT_ERR_PREFIX, Invalid_Table ) nuclear@0: nuclear@0: /* called when an invalid offset is detected */ nuclear@0: #define FT_INVALID_OFFSET \ nuclear@0: FT_INVALID( FT_ERR_PREFIX, Invalid_Offset ) nuclear@0: nuclear@0: /* called when an invalid format/value is detected */ nuclear@0: #define FT_INVALID_FORMAT \ nuclear@0: FT_INVALID( FT_ERR_PREFIX, Invalid_Table ) nuclear@0: nuclear@0: /* called when an invalid glyph index is detected */ nuclear@0: #define FT_INVALID_GLYPH_ID \ nuclear@0: FT_INVALID( FT_ERR_PREFIX, Invalid_Glyph_Index ) nuclear@0: nuclear@0: /* called when an invalid field value is detected */ nuclear@0: #define FT_INVALID_DATA \ nuclear@0: FT_INVALID( FT_ERR_PREFIX, Invalid_Table ) nuclear@0: nuclear@0: nuclear@0: FT_END_HEADER nuclear@0: nuclear@0: #endif /* __FTVALID_H__ */ nuclear@0: nuclear@0: nuclear@0: /* END */