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Editing: fterrors.h
/***************************************************************************/ /* */ /* fterrors.h */ /* */ /* FreeType error code handling (specification). */ /* */ /* Copyright 1996-2018 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. */ /* */ /***************************************************************************/ /*************************************************************************/ /* */ /* <Section> */ /* error_enumerations */ /* */ /* <Title> */ /* Error Enumerations */ /* */ /* <Abstract> */ /* How to handle errors and error strings. */ /* */ /* <Description> */ /* The header file `fterrors.h' (which is automatically included by */ /* `freetype.h' defines the handling of FreeType's enumeration */ /* constants. It can also be used to generate error message strings */ /* with a small macro trick explained below. */ /* */ /* *Error* *Formats* */ /* */ /* The configuration macro FT_CONFIG_OPTION_USE_MODULE_ERRORS can be */ /* defined in `ftoption.h' in order to make the higher byte indicate */ /* the module where the error has happened (this is not compatible */ /* with standard builds of FreeType~2, however). See the file */ /* `ftmoderr.h' for more details. */ /* */ /* *Error* *Message* *Strings* */ /* */ /* Error definitions are set up with special macros that allow client */ /* applications to build a table of error message strings. The */ /* strings are not included in a normal build of FreeType~2 to save */ /* space (most client applications do not use them). */ /* */ /* To do so, you have to define the following macros before including */ /* this file. */ /* */ /* { */ /* FT_ERROR_START_LIST */ /* } */ /* */ /* This macro is called before anything else to define the start of */ /* the error list. It is followed by several FT_ERROR_DEF calls. */ /* */ /* { */ /* FT_ERROR_DEF( e, v, s ) */ /* } */ /* */ /* This macro is called to define one single error. `e' is the error */ /* code identifier (e.g., `Invalid_Argument'), `v' is the error's */ /* numerical value, and `s' is the corresponding error string. */ /* */ /* { */ /* FT_ERROR_END_LIST */ /* } */ /* */ /* This macro ends the list. */ /* */ /* Additionally, you have to undefine `FTERRORS_H_' before #including */ /* this file. */ /* */ /* Here is a simple example. */ /* */ /* { */ /* #undef FTERRORS_H_ */ /* #define FT_ERRORDEF( e, v, s ) { e, s }, */ /* #define FT_ERROR_START_LIST { */ /* #define FT_ERROR_END_LIST { 0, NULL } }; */ /* */ /* const struct */ /* { */ /* int err_code; */ /* const char* err_msg; */ /* } ft_errors[] = */ /* */ /* #include FT_ERRORS_H */ /* } */ /* */ /* Note that `FT_Err_Ok' is _not_ defined with `FT_ERRORDEF' but with */ /* `FT_NOERRORDEF'; it is always zero. */ /* */ /*************************************************************************/ /* */ /* In previous FreeType versions we used `__FTERRORS_H__'. However, */ /* using two successive underscores in a non-system symbol name */ /* violates the C (and C++) standard, so it was changed to the */ /* current form. In spite of this, we have to make */ /* */ /* #undefine __FTERRORS_H__ */ /* */ /* work for backward compatibility. */ /* */ #if !( defined( FTERRORS_H_ ) && defined ( __FTERRORS_H__ ) ) #define FTERRORS_H_ #define __FTERRORS_H__ /* include module base error codes */ #include FT_MODULE_ERRORS_H /*******************************************************************/ /*******************************************************************/ /***** *****/ /***** SETUP MACROS *****/ /***** *****/ /*******************************************************************/ /*******************************************************************/ #undef FT_NEED_EXTERN_C /* FT_ERR_PREFIX is used as a prefix for error identifiers. */ /* By default, we use `FT_Err_'. */ /* */ #ifndef FT_ERR_PREFIX #define FT_ERR_PREFIX FT_Err_ #endif /* FT_ERR_BASE is used as the base for module-specific errors. */ /* */ #ifdef FT_CONFIG_OPTION_USE_MODULE_ERRORS #ifndef FT_ERR_BASE #define FT_ERR_BASE FT_Mod_Err_Base #endif #else #undef FT_ERR_BASE #define FT_ERR_BASE 0 #endif /* FT_CONFIG_OPTION_USE_MODULE_ERRORS */ /* If FT_ERRORDEF is not defined, we need to define a simple */ /* enumeration type. */ /* */ #ifndef FT_ERRORDEF #define FT_ERRORDEF( e, v, s ) e = v, #define FT_ERROR_START_LIST enum { #define FT_ERROR_END_LIST FT_ERR_CAT( FT_ERR_PREFIX, Max ) }; #ifdef __cplusplus #define FT_NEED_EXTERN_C extern "C" { #endif #endif /* !FT_ERRORDEF */ /* this macro is used to define an error */ #define FT_ERRORDEF_( e, v, s ) \ FT_ERRORDEF( FT_ERR_CAT( FT_ERR_PREFIX, e ), v + FT_ERR_BASE, s ) /* this is only used for <module>_Err_Ok, which must be 0! */ #define FT_NOERRORDEF_( e, v, s ) \ FT_ERRORDEF( FT_ERR_CAT( FT_ERR_PREFIX, e ), v, s ) #ifdef FT_ERROR_START_LIST FT_ERROR_START_LIST #endif /* now include the error codes */ #include FT_ERROR_DEFINITIONS_H #ifdef FT_ERROR_END_LIST FT_ERROR_END_LIST #endif /*******************************************************************/ /*******************************************************************/ /***** *****/ /***** SIMPLE CLEANUP *****/ /***** *****/ /*******************************************************************/ /*******************************************************************/ #ifdef FT_NEED_EXTERN_C } #endif #undef FT_ERROR_START_LIST #undef FT_ERROR_END_LIST #undef FT_ERRORDEF #undef FT_ERRORDEF_ #undef FT_NOERRORDEF_ #undef FT_NEED_EXTERN_C #undef FT_ERR_BASE /* FT_ERR_PREFIX is needed internally */ #ifndef FT2_BUILD_LIBRARY #undef FT_ERR_PREFIX #endif #endif /* !(FTERRORS_H_ && __FTERRORS_H__) */ /* END */
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