ffmpeg/libavutil/internal.h
2013-02-08 23:13:37 +01:00

178 lines
5.0 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
// Some broken preprocessors need a second expansion
// to be forced to tokenize __VA_ARGS__
#define E(x) x
#define LOCAL_ALIGNED_A(a, t, v, s, o, ...) \
uint8_t la_##v[sizeof(t s o) + (a)]; \
t (*v) o = (void *)FFALIGN((uintptr_t)la_##v, a)
#define LOCAL_ALIGNED_D(a, t, v, s, o, ...) \
DECLARE_ALIGNED(a, t, la_##v) s o; \
t (*v) o = la_##v
#define LOCAL_ALIGNED(a, t, v, ...) E(LOCAL_ALIGNED_A(a, t, v, __VA_ARGS__,,))
#if HAVE_LOCAL_ALIGNED_8
# define LOCAL_ALIGNED_8(t, v, ...) E(LOCAL_ALIGNED_D(8, t, v, __VA_ARGS__,,))
#else
# define LOCAL_ALIGNED_8(t, v, ...) LOCAL_ALIGNED(8, t, v, __VA_ARGS__)
#endif
#if HAVE_LOCAL_ALIGNED_16
# define LOCAL_ALIGNED_16(t, v, ...) E(LOCAL_ALIGNED_D(16, t, v, __VA_ARGS__,,))
#else
# define LOCAL_ALIGNED_16(t, v, ...) LOCAL_ALIGNED(16, t, v, __VA_ARGS__)
#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
#elif HAVE_MMX && HAVE_YASM
# include "libavutil/x86/emms.h"
# define emms_c avpriv_emms_yasm
#else
# define emms_c()
#endif /* HAVE_MMX_INLINE */
#endif /* AVUTIL_INTERNAL_H */