ffmpeg/libavutil/internal.h

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/*
* 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() 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
Add support for building shared libraries with MSVC This requires the makedef perl script by Derek, from the c89-to-c99 repo. That scripts produces a .def file, listing the symbols to be exported, based on the gcc version scripts and the built object files. To properly load non-function symbols from DLL files, the data symbol declarations need to have the attribute __declspec(dllimport) when building the calling code. (On mingw, the linker can fix this up automatically, which is why it has not been an issue so far. If this attribute is omitted, linking actually succeeds, but reads from the table will not produce the desired results at runtime.) MSVC seems to manage to link DLLs (and run properly) even if this attribute is present while building the library itself (which normally isn't recommended) - other object files in the same library manage to link to the symbol (with a small warning at link time, like "warning LNK4049: locally defined symbol _avpriv_mpa_bitrate_tab imported" - it doesn't seem to be possible to squelch this warning), and the definition of the tables themselves produce a warning that can be squelched ("warning C4273: 'avpriv_mpa_bitrate_tab' : inconsistent dll linkage, see previous definition of 'avpriv_mpa_bitrate_tab'). In this setup, mingw isn't able to link object files that refer to data symbols with __declspec(dllimport) without those symbols actually being linked via a DLL (linking avcodec.dll ends up with errors like "undefined reference to `__imp__avpriv_mpa_freq_tab'"). The dllimport declspec isn't needed at all in mingw, so we simply choose not to declare it for other compilers than MSVC that requires it. (If ICL support later requires it, the condition can be extended later to include both of them.) This also implies that code that is built to link to a certain library as a DLL can't link to the same library as a static library. Therefore, we only allow building either static or shared but not both at the same time. (That is, static libraries as such can be, and actually are, built - this is used for linking the test tools to internal symbols in the libraries - but e.g. libavformat built to link to libavcodec as a DLL cannot link statically to libavcodec.) Also, linking to DLLs is slightly different from linking to shared libraries on other platforms. DLLs use a thing called import libraries, which is basically a stub library allowing the linker to know which symbols exist in the DLL and what name the DLL will have at runtime. In mingw/gcc, the import library is usually named libfoo.dll.a, which goes next to a static library named libfoo.a. This allows gcc to pick the dynamic one, if available, from the normal -lfoo switches, just as it does for libfoo.a vs libfoo.so on Unix. On MSVC however, you need to literally specify the name of the import library instead of the static library. Signed-off-by: Martin Storsjö <martin@martin.st>
2012-10-18 08:53:19 +00:00
#if defined(_MSC_VER) && CONFIG_SHARED
# define av_export __declspec(dllimport)
#else
# define av_export
#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 ignored \"-Wdeprecated-declarations\"")
# define FF_ENABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic warning \"-Wdeprecated-declarations\"")
# 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; }
// Some broken preprocessors need a second expansion
// to be forced to tokenize __VA_ARGS__
#define E1(x) x
/* 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 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, ...) E1(LOCAL_ALIGNED_A(a, t, v, __VA_ARGS__,,))
#if HAVE_LOCAL_ALIGNED_8
# define LOCAL_ALIGNED_8(t, v, ...) E1(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, ...) E1(LOCAL_ALIGNED_D(16, t, v, __VA_ARGS__,,))
#else
# define LOCAL_ALIGNED_16(t, v, ...) LOCAL_ALIGNED(16, t, v, __VA_ARGS__)
#endif
#if HAVE_LOCAL_ALIGNED_32
# define LOCAL_ALIGNED_32(t, v, ...) E1(LOCAL_ALIGNED_D(32, t, v, __VA_ARGS__,,))
#else
# define LOCAL_ALIGNED_32(t, v, ...) LOCAL_ALIGNED(32, t, v, __VA_ARGS__)
#endif
#define FF_ALLOC_OR_GOTO(ctx, p, size, label)\
{\
p = av_malloc(size);\
if (!(p) && (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) && (size) != 0) {\
av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
goto label;\
}\
}
#define FF_ALLOC_ARRAY_OR_GOTO(ctx, p, nelem, elsize, label)\
{\
p = av_malloc_array(nelem, elsize);\
if (!p) {\
av_log(ctx, AV_LOG_ERROR, "Cannot allocate memory.\n");\
goto label;\
}\
}
#define FF_ALLOCZ_ARRAY_OR_GOTO(ctx, p, nelem, elsize, label)\
{\
p = av_mallocz_array(nelem, elsize);\
if (!p) {\
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
* 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
2015-08-18 00:27:25 +00:00
#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)
2015-12-07 18:42:28 +00:00
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 s AVFormatContext
* @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);
#endif /* AVUTIL_INTERNAL_H */