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/****************************************************************************
*
* internal/compiler-macros.h
*
* Compiler-specific macro definitions used internally by FreeType.
*
* Copyright (C) 2020-2022 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 INTERNAL_COMPILER_MACROS_H_
#define INTERNAL_COMPILER_MACROS_H_
#include <freetype/config/public-macros.h>
FT_BEGIN_HEADER
/* Fix compiler warning with sgi compiler. */
#if defined( __sgi ) && !defined( __GNUC__ )
# if defined( _COMPILER_VERSION ) && ( _COMPILER_VERSION >= 730 )
# pragma set woff 3505
# endif
#endif
/* Fix compiler warning with sgi compiler. */
#if defined( __sgi ) && !defined( __GNUC__ )
# if defined( _COMPILER_VERSION ) && ( _COMPILER_VERSION >= 730 )
# pragma set woff 3505
# endif
#endif
/*
* When defining a macro that expands to a non-trivial C statement, use
* FT_BEGIN_STMNT and FT_END_STMNT to enclose the macro's body. This
* ensures there are no surprises when the macro is invoked in conditional
* branches.
*
* Example:
*
* #define LOG( ... ) \
* FT_BEGIN_STMNT \
* if ( logging_enabled ) \
* log( __VA_ARGS__ ); \
* FT_END_STMNT
*/
#define FT_BEGIN_STMNT do {
#define FT_END_STMNT } while ( 0 )
/*
* FT_DUMMY_STMNT expands to an empty C statement. Useful for
* conditionally defined statement macros.
*
* Example:
*
* #ifdef BUILD_CONFIG_LOGGING
* #define LOG( ... ) \
* FT_BEGIN_STMNT \
* if ( logging_enabled ) \
* log( __VA_ARGS__ ); \
* FT_END_STMNT
* #else
* # define LOG( ... ) FT_DUMMY_STMNT
* #endif
*/
#define FT_DUMMY_STMNT FT_BEGIN_STMNT FT_END_STMNT
#ifdef __UINTPTR_TYPE__
/*
* GCC and Clang both provide a `__UINTPTR_TYPE__` that can be used to
* avoid a dependency on `stdint.h`.
*/
# define FT_UINT_TO_POINTER( x ) (void *)(__UINTPTR_TYPE__)(x)
#elif defined( _WIN64 )
/* only 64bit Windows uses the LLP64 data model, i.e., */
/* 32-bit integers, 64-bit pointers. */
# define FT_UINT_TO_POINTER( x ) (void *)(unsigned __int64)(x)
#else
# define FT_UINT_TO_POINTER( x ) (void *)(unsigned long)(x)
#endif
/*
* Use `FT_TYPEOF( type )` to cast a value to `type`. This is useful to
* suppress signedness compilation warnings in macros.
*
* Example:
*
* #define PAD_( x, n ) ( (x) & ~FT_TYPEOF( x )( (n) - 1 ) )
*
* (The `typeof` condition is taken from gnulib's `intprops.h` header
* file.)
*/
#if ( ( defined( __GNUC__ ) && __GNUC__ >= 2 ) || \
( defined( __IBMC__ ) && __IBMC__ >= 1210 && \
defined( __IBM__TYPEOF__ ) ) || \
( defined( __SUNPRO_C ) && __SUNPRO_C >= 0x5110 && !__STDC__ ) )
#define FT_TYPEOF( type ) ( __typeof__ ( type ) )
#else
#define FT_TYPEOF( type ) /* empty */
#endif
/*
* Mark a function declaration as internal to the library. This ensures
* that it will not be exposed by default to client code, and helps
* generate smaller and faster code on ELF-based platforms. Place this
* before a function declaration.
*/
/* Visual C, mingw */
#if defined( _WIN32 )
#define FT_INTERNAL_FUNCTION_ATTRIBUTE /* empty */
/* gcc, clang */
#elif ( defined( __GNUC__ ) && __GNUC__ >= 4 ) || defined( __clang__ )
#define FT_INTERNAL_FUNCTION_ATTRIBUTE \
__attribute__(( visibility( "hidden" ) ))
/* Sun */
#elif defined( __SUNPRO_C ) && __SUNPRO_C >= 0x550
#define FT_INTERNAL_FUNCTION_ATTRIBUTE __hidden
#else
#define FT_INTERNAL_FUNCTION_ATTRIBUTE /* empty */
#endif
/*
* FreeType supports compilation of its C sources with a C++ compiler (in
* C++ mode); this introduces a number of subtle issues.
*
* The main one is that a C++ function declaration and its definition must
* have the same 'linkage'. Because all FreeType headers declare their
* functions with C linkage (i.e., within an `extern "C" { ... }` block
* due to the magic of FT_BEGIN_HEADER and FT_END_HEADER), their
* definition in FreeType sources should also be prefixed with `extern
* "C"` when compiled in C++ mode.
*
* The `FT_FUNCTION_DECLARATION` and `FT_FUNCTION_DEFINITION` macros are
* provided to deal with this case, as well as `FT_CALLBACK_DEF` and its
* siblings below.
*/
/*
* `FT_FUNCTION_DECLARATION( type )` can be used to write a C function
* declaration to ensure it will have C linkage when the library is built
* with a C++ compiler. The parameter is the function's return type, so a
* declaration would look like
*
* FT_FUNCTION_DECLARATION( int )
* foo( int x );
*
* NOTE: This requires that all uses are inside of `FT_BEGIN_HEADER ...
* FT_END_HEADER` blocks, which guarantees that the declarations have C
* linkage when the headers are included by C++ sources.
*
* NOTE: Do not use directly. Use `FT_LOCAL`, `FT_BASE`, and `FT_EXPORT`
* instead.
*/
#define FT_FUNCTION_DECLARATION( x ) extern x
/*
* Same as `FT_FUNCTION_DECLARATION`, but for function definitions instead.
*
* NOTE: Do not use directly. Use `FT_LOCAL_DEF`, `FT_BASE_DEF`, and
* `FT_EXPORT_DEF` instead.
*/
#ifdef __cplusplus
#define FT_FUNCTION_DEFINITION( x ) extern "C" x
#else
#define FT_FUNCTION_DEFINITION( x ) x
#endif
/*
* Use `FT_LOCAL` and `FT_LOCAL_DEF` to declare and define, respectively,
* an internal FreeType function that is only used by the sources of a
* single `src/module/` directory. This ensures that the functions are
* turned into static ones at build time, resulting in smaller and faster
* code.
*/
#ifdef FT_MAKE_OPTION_SINGLE_OBJECT
#define FT_LOCAL( x ) static x
#define FT_LOCAL_DEF( x ) static x
#else
#define FT_LOCAL( x ) FT_INTERNAL_FUNCTION_ATTRIBUTE \
FT_FUNCTION_DECLARATION( x )
#define FT_LOCAL_DEF( x ) FT_FUNCTION_DEFINITION( x )
#endif /* FT_MAKE_OPTION_SINGLE_OBJECT */
/*
* Use `FT_LOCAL_ARRAY` and `FT_LOCAL_ARRAY_DEF` to declare and define,
* respectively, a constant array that must be accessed from several
* sources in the same `src/module/` sub-directory, and which are internal
* to the library.
*/
#define FT_LOCAL_ARRAY( x ) FT_INTERNAL_FUNCTION_ATTRIBUTE \
extern const x
#define FT_LOCAL_ARRAY_DEF( x ) FT_FUNCTION_DEFINITION( const x )
/*
* `Use FT_BASE` and `FT_BASE_DEF` to declare and define, respectively, an
* internal library function that is used by more than a single module.
*/
#define FT_BASE( x ) FT_INTERNAL_FUNCTION_ATTRIBUTE \
FT_FUNCTION_DECLARATION( x )
#define FT_BASE_DEF( x ) FT_FUNCTION_DEFINITION( x )
/*
* NOTE: Conditionally define `FT_EXPORT_VAR` due to its definition in
* `src/smooth/ftgrays.h` to make the header more portable.
*/
#ifndef FT_EXPORT_VAR
#define FT_EXPORT_VAR( x ) FT_FUNCTION_DECLARATION( x )
#endif
/*
* When compiling FreeType as a DLL or DSO with hidden visibility,
* some systems/compilers need a special attribute in front OR after
* the return type of function declarations.
*
* Two macros are used within the FreeType source code to define
* exported library functions: `FT_EXPORT` and `FT_EXPORT_DEF`.
*
* - `FT_EXPORT( return_type )`
*
* is used in a function declaration, as in
*
* ```
* FT_EXPORT( FT_Error )
* FT_Init_FreeType( FT_Library* alibrary );
* ```
*
* - `FT_EXPORT_DEF( return_type )`
*
* is used in a function definition, as in
*
* ```
* FT_EXPORT_DEF( FT_Error )
* FT_Init_FreeType( FT_Library* alibrary )
* {
* ... some code ...
* return FT_Err_Ok;
* }
* ```
*
* You can provide your own implementation of `FT_EXPORT` and
* `FT_EXPORT_DEF` here if you want.
*
* To export a variable, use `FT_EXPORT_VAR`.
*/
/* See `freetype/config/compiler_macros.h` for the `FT_EXPORT` definition */
#define FT_EXPORT_DEF( x ) FT_FUNCTION_DEFINITION( x )
/*
* The following macros are needed to compile the library with a
* C++ compiler and with 16bit compilers.
*/
/*
* This is special. Within C++, you must specify `extern "C"` for
* functions which are used via function pointers, and you also
* must do that for structures which contain function pointers to
* assure C linkage -- it's not possible to have (local) anonymous
* functions which are accessed by (global) function pointers.
*
*
* FT_CALLBACK_DEF is used to _define_ a callback function,
* located in the same source code file as the structure that uses
* it. FT_COMPARE_DEF, in addition, ensures the `cdecl` calling
* convention on x86, required by the C library function `qsort`.
*
* FT_BASE_CALLBACK and FT_BASE_CALLBACK_DEF are used to declare
* and define a callback function, respectively, in a similar way
* as FT_BASE and FT_BASE_DEF work.
*
* FT_CALLBACK_TABLE is used to _declare_ a constant variable that
* contains pointers to callback functions.
*
* FT_CALLBACK_TABLE_DEF is used to _define_ a constant variable
* that contains pointers to callback functions.
*
*
* Some 16bit compilers have to redefine these macros to insert
* the infamous `_cdecl` or `__fastcall` declarations.
*/
#ifdef __cplusplus
#define FT_CALLBACK_DEF( x ) extern "C" x
#else
#define FT_CALLBACK_DEF( x ) static x
#endif
#if defined( __GNUC__ ) && defined( __i386__ )
#define FT_COMPARE_DEF( x ) FT_CALLBACK_DEF( x ) __attribute__(( cdecl ))
#elif defined( _MSC_VER ) && defined( _M_IX86 )
#define FT_COMPARE_DEF( x ) FT_CALLBACK_DEF( x ) __cdecl
#elif defined( __WATCOMC__ ) && __WATCOMC__ >= 1240
#define FT_COMPARE_DEF( x ) FT_CALLBACK_DEF( x ) __watcall
#else
#define FT_COMPARE_DEF( x ) FT_CALLBACK_DEF( x )
#endif
#define FT_BASE_CALLBACK( x ) FT_FUNCTION_DECLARATION( x )
#define FT_BASE_CALLBACK_DEF( x ) FT_FUNCTION_DEFINITION( x )
#ifndef FT_CALLBACK_TABLE
#ifdef __cplusplus
#define FT_CALLBACK_TABLE extern "C"
#define FT_CALLBACK_TABLE_DEF extern "C"
#else
#define FT_CALLBACK_TABLE extern
#define FT_CALLBACK_TABLE_DEF /* nothing */
#endif
#endif /* FT_CALLBACK_TABLE */
FT_END_HEADER
#endif /* INTERNAL_COMPILER_MACROS_H_ */