ref: a2b5f66bf5eaf393eb800ac402c74f69534b74ba
dir: /include/internal/ftvalid.h/
/***************************************************************************/ /* */ /* ftvalid.h */ /* */ /* FreeType validation support (specification). */ /* */ /* Copyright 2004, 2013 by */ /* 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. */ /* */ /***************************************************************************/ #ifndef __FTVALID_H__ #define __FTVALID_H__ #include <ft2build.h> #include FT_CONFIG_STANDARD_LIBRARY_H /* for ft_setjmp and ft_longjmp */ FT_BEGIN_HEADER /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /**** ****/ /**** ****/ /**** V A L I D A T I O N ****/ /**** ****/ /**** ****/ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /* handle to a validation object */ typedef struct FT_ValidatorRec_ volatile* FT_Validator; /*************************************************************************/ /* */ /* There are three distinct validation levels defined here: */ /* */ /* FT_VALIDATE_DEFAULT :: */ /* A table that passes this validation level can be used reliably by */ /* FreeType. It generally means that all offsets have been checked to */ /* prevent out-of-bound reads, that array counts are correct, etc. */ /* */ /* FT_VALIDATE_TIGHT :: */ /* A table that passes this validation level can be used reliably and */ /* doesn't contain invalid data. For example, a charmap table that */ /* returns invalid glyph indices will not pass, even though it can */ /* be used with FreeType in default mode (the library will simply */ /* return an error later when trying to load the glyph). */ /* */ /* It also checks that fields which must be a multiple of 2, 4, or 8, */ /* don't have incorrect values, etc. */ /* */ /* FT_VALIDATE_PARANOID :: */ /* Only for font debugging. Checks that a table follows the */ /* specification by 100%. Very few fonts will be able to pass this */ /* level anyway but it can be useful for certain tools like font */ /* editors/converters. */ /* */ typedef enum FT_ValidationLevel_ { FT_VALIDATE_DEFAULT = 0, FT_VALIDATE_TIGHT, FT_VALIDATE_PARANOID } FT_ValidationLevel; #if defined( _MSC_VER ) /* Visual C++ (and Intel C++) */ /* We disable the warning `structure was padded due to */ /* __declspec(align())' in order to compile cleanly with */ /* the maximum level of warnings. */ #pragma warning( push ) #pragma warning( disable : 4324 ) #endif /* _MSC_VER */ /* validator structure */ typedef struct FT_ValidatorRec_ { const FT_Byte* base; /* address of table in memory */ const FT_Byte* limit; /* `base' + sizeof(table) in memory */ FT_ValidationLevel level; /* validation level */ FT_Error error; /* error returned. 0 means success */ ft_jmp_buf jump_buffer; /* used for exception handling */ } FT_ValidatorRec; #if defined( _MSC_VER ) #pragma warning( pop ) #endif #define FT_VALIDATOR( x ) ( (FT_Validator)( x ) ) FT_BASE( void ) ft_validator_init( FT_Validator valid, const FT_Byte* base, const FT_Byte* limit, FT_ValidationLevel level ); /* Do not use this. It's broken and will cause your validator to crash */ /* if you run it on an invalid font. */ FT_BASE( FT_Int ) ft_validator_run( FT_Validator valid ); /* Sets the error field in a validator, then calls `longjmp' to return */ /* to high-level caller. Using `setjmp/longjmp' avoids many stupid */ /* error checks within the validation routines. */ /* */ FT_BASE( void ) ft_validator_error( FT_Validator valid, FT_Error error ); /* Calls ft_validate_error. Assumes that the `valid' local variable */ /* holds a pointer to the current validator object. */ /* */ /* Use preprocessor prescan to pass FT_ERR_PREFIX. */ /* */ #define FT_INVALID( _prefix, _error ) FT_INVALID_( _prefix, _error ) #define FT_INVALID_( _prefix, _error ) \ ft_validator_error( valid, _prefix ## _error ) /* called when a broken table is detected */ #define FT_INVALID_TOO_SHORT \ FT_INVALID( FT_ERR_PREFIX, Invalid_Table ) /* called when an invalid offset is detected */ #define FT_INVALID_OFFSET \ FT_INVALID( FT_ERR_PREFIX, Invalid_Offset ) /* called when an invalid format/value is detected */ #define FT_INVALID_FORMAT \ FT_INVALID( FT_ERR_PREFIX, Invalid_Table ) /* called when an invalid glyph index is detected */ #define FT_INVALID_GLYPH_ID \ FT_INVALID( FT_ERR_PREFIX, Invalid_Glyph_Index ) /* called when an invalid field value is detected */ #define FT_INVALID_DATA \ FT_INVALID( FT_ERR_PREFIX, Invalid_Table ) FT_END_HEADER #endif /* __FTVALID_H__ */ /* END */