/***************************************************************************/ | |
/* */ | |
/* ftvalid.h */ | |
/* */ | |
/* FreeType validation support (specification). */ | |
/* */ | |
/* Copyright 2004-2015 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_ | |
{ | |
ft_jmp_buf jump_buffer; /* used for exception handling */ | |
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_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. */ | |
/* */ | |
#define FT_INVALID( _error ) FT_INVALID_( _error ) | |
#define FT_INVALID_( _error ) \ | |
ft_validator_error( valid, FT_THROW( _error ) ) | |
/* called when a broken table is detected */ | |
#define FT_INVALID_TOO_SHORT \ | |
FT_INVALID( Invalid_Table ) | |
/* called when an invalid offset is detected */ | |
#define FT_INVALID_OFFSET \ | |
FT_INVALID( Invalid_Offset ) | |
/* called when an invalid format/value is detected */ | |
#define FT_INVALID_FORMAT \ | |
FT_INVALID( Invalid_Table ) | |
/* called when an invalid glyph index is detected */ | |
#define FT_INVALID_GLYPH_ID \ | |
FT_INVALID( Invalid_Glyph_Index ) | |
/* called when an invalid field value is detected */ | |
#define FT_INVALID_DATA \ | |
FT_INVALID( Invalid_Table ) | |
FT_END_HEADER | |
#endif /* __FTVALID_H__ */ | |
/* END */ |