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mirror of https://git.videolan.org/git/ffmpeg.git synced 2024-09-16 11:54:09 +02:00
ffmpeg/libavutil/internal.h
Janne Grunau e96d90eed6 remove #defines to prevent use of discouraged external functions
Preventing the use of discouraged or 'insecure' external functions
through defines in an internal header is not a good solution. The
header is not guaranteed to be included universally which makes
overlooking bad use of said functions during review more likely.

There are cases were those functions either are the most straight
forward solution or even have to be used. Using malloc or free is
required if the allocation or release is done by other libraries.
2012-11-25 23:02:04 +01:00

149 lines
4.0 KiB
C

/*
* copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* common internal API header
*/
#ifndef AVUTIL_INTERNAL_H
#define AVUTIL_INTERNAL_H
#if !defined(DEBUG) && !defined(NDEBUG)
# define NDEBUG
#endif
#include <limits.h>
#include <stdint.h>
#include <stddef.h>
#include <assert.h>
#include "config.h"
#include "attributes.h"
#include "timer.h"
#include "dict.h"
#ifndef attribute_align_arg
#if ARCH_X86_32 && AV_GCC_VERSION_AT_LEAST(4,2)
# define attribute_align_arg __attribute__((force_align_arg_pointer))
#else
# define attribute_align_arg
#endif
#endif
#if defined(_MSC_VER) && CONFIG_SHARED
# define av_export __declspec(dllimport)
#else
# define av_export
#endif
#ifndef INT_BIT
# define INT_BIT (CHAR_BIT * sizeof(int))
#endif
#define FF_ALLOC_OR_GOTO(ctx, p, size, label)\
{\
p = av_malloc(size);\
if (p == NULL && (size) != 0) {\
av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
goto label;\
}\
}
#define FF_ALLOCZ_OR_GOTO(ctx, p, size, label)\
{\
p = av_mallocz(size);\
if (p == NULL && (size) != 0) {\
av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
goto label;\
}\
}
#include "libm.h"
/**
* Return NULL if CONFIG_SMALL is true, otherwise the argument
* without modification. Used to disable the definition of strings
* (for example AVCodec long_names).
*/
#if CONFIG_SMALL
# define NULL_IF_CONFIG_SMALL(x) NULL
#else
# define NULL_IF_CONFIG_SMALL(x) x
#endif
/**
* Define a function with only the non-default version specified.
*
* On systems with ELF shared libraries, all symbols exported from
* Libav libraries are tagged with the name and major version of the
* library to which they belong. If a function is moved from one
* library to another, a wrapper must be retained in the original
* location to preserve binary compatibility.
*
* Functions defined with this macro will never be used to resolve
* symbols by the build-time linker.
*
* @param type return type of function
* @param name name of function
* @param args argument list of function
* @param ver version tag to assign function
*/
#if HAVE_SYMVER_ASM_LABEL
# define FF_SYMVER(type, name, args, ver) \
type ff_##name args __asm__ (EXTERN_PREFIX #name "@" ver); \
type ff_##name args
#elif HAVE_SYMVER_GNU_ASM
# define FF_SYMVER(type, name, args, ver) \
__asm__ (".symver ff_" #name "," EXTERN_PREFIX #name "@" ver); \
type ff_##name args; \
type ff_##name args
#endif
/**
* Return NULL if a threading library has not been enabled.
* Used to disable threading functions in AVCodec definitions
* when not needed.
*/
#if HAVE_THREADS
# define ONLY_IF_THREADS_ENABLED(x) x
#else
# define ONLY_IF_THREADS_ENABLED(x) NULL
#endif
#if HAVE_MMX_INLINE
/**
* Empty mmx state.
* this must be called between any dsp function and float/double code.
* for example sin(); dsp->idct_put(); emms_c(); cos()
*/
static av_always_inline void emms_c(void)
{
__asm__ volatile ("emms" ::: "memory");
}
#elif HAVE_MMX && HAVE_MM_EMPTY
# include <mmintrin.h>
# define emms_c _mm_empty
#else
# define emms_c()
#endif /* HAVE_MMX_INLINE */
#endif /* AVUTIL_INTERNAL_H */