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Diffstat (limited to 'modules/freetype2/include/freetype/internal/ftvalid.h')
| -rw-r--r-- | modules/freetype2/include/freetype/internal/ftvalid.h | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/modules/freetype2/include/freetype/internal/ftvalid.h b/modules/freetype2/include/freetype/internal/ftvalid.h new file mode 100644 index 0000000000..e98ee4e473 --- /dev/null +++ b/modules/freetype2/include/freetype/internal/ftvalid.h @@ -0,0 +1,160 @@ +/**************************************************************************** + * + * ftvalid.h + * + * FreeType validation support (specification). + * + * Copyright (C) 2004-2023 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_jmpbuf */ + +#include "compiler-macros.h" + +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 */ |