ffmpeg/libavutil/internal.h

303 lines
9.7 KiB
C

/*
* copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; 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
// This can be enabled to allow detection of additional integer overflows with ubsan
//#define CHECKED
#include <limits.h>
#include <stdint.h>
#include <stddef.h>
#include <assert.h>
#include "config.h"
#include "attributes.h"
#include "timer.h"
#include "cpu.h"
#include "dict.h"
#include "macros.h"
#include "pixfmt.h"
#include "version.h"
#if ARCH_X86
# include "x86/emms.h"
#endif
#ifndef emms_c
# define emms_c() do {} while(0)
#endif
#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(_WIN32) && CONFIG_SHARED && !defined(BUILDING_avutil)
# define av_export_avutil __declspec(dllimport)
#else
# define av_export_avutil
#endif
#if HAVE_PRAGMA_DEPRECATED
# if defined(__ICL) || defined (__INTEL_COMPILER)
# define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:1478))
# define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
# elif defined(_MSC_VER)
# define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:4996))
# define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
# else
# define FF_DISABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic push") _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
# define FF_ENABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic pop")
# endif
#else
# define FF_DISABLE_DEPRECATION_WARNINGS
# define FF_ENABLE_DEPRECATION_WARNINGS
#endif
#define FF_MEMORY_POISON 0x2a
#define MAKE_ACCESSORS(str, name, type, field) \
type av_##name##_get_##field(const str *s) { return s->field; } \
void av_##name##_set_##field(str *s, type v) { s->field = v; }
/* Check if the hard coded offset of a struct member still matches reality.
* Induce a compilation failure if not.
*/
#define AV_CHECK_OFFSET(s, m, o) struct check_##o { \
int x_##o[offsetof(s, m) == o? 1: -1]; \
}
#define FF_ALLOC_TYPED_ARRAY(p, nelem) (p = av_malloc_array(nelem, sizeof(*p)))
#define FF_ALLOCZ_TYPED_ARRAY(p, nelem) (p = av_mallocz_array(nelem, sizeof(*p)))
#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
* FFmpeg 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
/**
* Log a generic warning message about a missing feature.
*
* @param[in] avc a pointer to an arbitrary struct of which the first
* field is a pointer to an AVClass struct
* @param[in] msg string containing the name of the missing feature
*/
void avpriv_report_missing_feature(void *avc,
const char *msg, ...) av_printf_format(2, 3);
/**
* Log a generic warning message about a missing feature.
* Additionally request that a sample showcasing the feature be uploaded.
*
* @param[in] avc a pointer to an arbitrary struct of which the first field is
* a pointer to an AVClass struct
* @param[in] msg string containing the name of the missing feature
*/
void avpriv_request_sample(void *avc,
const char *msg, ...) av_printf_format(2, 3);
#if HAVE_LIBC_MSVCRT
#include <crtversion.h>
#if defined(_VC_CRT_MAJOR_VERSION) && _VC_CRT_MAJOR_VERSION < 14
#pragma comment(linker, "/include:" EXTERN_PREFIX "avpriv_strtod")
#pragma comment(linker, "/include:" EXTERN_PREFIX "avpriv_snprintf")
#endif
#define avpriv_open ff_open
#define avpriv_tempfile ff_tempfile
#define PTRDIFF_SPECIFIER "Id"
#define SIZE_SPECIFIER "Iu"
#else
#define PTRDIFF_SPECIFIER "td"
#define SIZE_SPECIFIER "zu"
#endif
#ifdef DEBUG
# define ff_dlog(ctx, ...) av_log(ctx, AV_LOG_DEBUG, __VA_ARGS__)
#else
# define ff_dlog(ctx, ...) do { if (0) av_log(ctx, AV_LOG_DEBUG, __VA_ARGS__); } while (0)
#endif
// For debuging we use signed operations so overflows can be detected (by ubsan)
// For production we use unsigned so there are no undefined operations
#ifdef CHECKED
#define SUINT int
#define SUINT32 int32_t
#else
#define SUINT unsigned
#define SUINT32 uint32_t
#endif
/**
* Clip and convert a double value into the long long amin-amax range.
* This function is needed because conversion of floating point to integers when
* it does not fit in the integer's representation does not necessarily saturate
* correctly (usually converted to a cvttsd2si on x86) which saturates numbers
* > INT64_MAX to INT64_MIN. The standard marks such conversions as undefined
* behavior, allowing this sort of mathematically bogus conversions. This provides
* a safe alternative that is slower obviously but assures safety and better
* mathematical behavior.
* @param a value to clip
* @param amin minimum value of the clip range
* @param amax maximum value of the clip range
* @return clipped value
*/
static av_always_inline av_const int64_t ff_rint64_clip(double a, int64_t amin, int64_t amax)
{
int64_t res;
#if defined(HAVE_AV_CONFIG_H) && defined(ASSERT_LEVEL) && ASSERT_LEVEL >= 2
if (amin > amax) abort();
#endif
// INT64_MAX+1,INT64_MIN are exactly representable as IEEE doubles
// do range checks first
if (a >= 9223372036854775808.0)
return amax;
if (a <= -9223372036854775808.0)
return amin;
// safe to call llrint and clip accordingly
res = llrint(a);
if (res > amax)
return amax;
if (res < amin)
return amin;
return res;
}
/**
* A wrapper for open() setting O_CLOEXEC.
*/
av_warn_unused_result
int avpriv_open(const char *filename, int flags, ...);
/**
* Wrapper to work around the lack of mkstemp() on mingw.
* Also, tries to create file in /tmp first, if possible.
* *prefix can be a character constant; *filename will be allocated internally.
* @return file descriptor of opened file (or negative value corresponding to an
* AVERROR code on error)
* and opened file name in **filename.
* @note On very old libcs it is necessary to set a secure umask before
* calling this, av_tempfile() can't call umask itself as it is used in
* libraries and could interfere with the calling application.
*/
int avpriv_tempfile(const char *prefix, char **filename, int log_offset, void *log_ctx);
int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt);
static av_always_inline av_const int avpriv_mirror(int x, int w)
{
if (!w)
return 0;
while ((unsigned)x > (unsigned)w) {
x = -x;
if (x < 0)
x += 2 * w;
}
return x;
}
void ff_check_pixfmt_descriptors(void);
/**
* Set a dictionary value to an ISO-8601 compliant timestamp string.
*
* @param dict pointer to a pointer to a dictionary struct. If *dict is NULL
* a dictionary struct is allocated and put in *dict.
* @param key metadata key
* @param timestamp unix timestamp in microseconds
* @return <0 on error
*/
int avpriv_dict_set_timestamp(AVDictionary **dict, const char *key, int64_t timestamp);
// Helper macro for AV_PIX_FMT_FLAG_PSEUDOPAL deprecation. Code inside FFmpeg
// should always use FF_PSEUDOPAL. Once the public API flag gets removed, all
// code using it is dead code.
#if FF_API_PSEUDOPAL
#define FF_PSEUDOPAL AV_PIX_FMT_FLAG_PSEUDOPAL
#else
#define FF_PSEUDOPAL 0
#endif
#endif /* AVUTIL_INTERNAL_H */