FFmpeg
internal.h
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1 /*
2  * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * common internal API header
24  */
25 
26 #ifndef AVUTIL_INTERNAL_H
27 #define AVUTIL_INTERNAL_H
28 
29 #if !defined(DEBUG) && !defined(NDEBUG)
30 # define NDEBUG
31 #endif
32 
33 // This can be enabled to allow detection of additional integer overflows with ubsan
34 //#define CHECKED
35 
36 #include <limits.h>
37 #include <stdint.h>
38 #include <stddef.h>
39 #include <assert.h>
40 #include <stdio.h>
41 #include "config.h"
42 #include "attributes.h"
43 #include "macros.h"
44 #include "pixfmt.h"
45 
46 #ifndef attribute_align_arg
47 #if ARCH_X86_32 && AV_GCC_VERSION_AT_LEAST(4,2)
48 # define attribute_align_arg __attribute__((force_align_arg_pointer))
49 #else
50 # define attribute_align_arg
51 #endif
52 #endif
53 
54 #if defined(_WIN32) && CONFIG_SHARED && !defined(BUILDING_avutil)
55 # define av_export_avutil __declspec(dllimport)
56 #else
57 # define av_export_avutil
58 #endif
59 
60 #if HAVE_PRAGMA_DEPRECATED
61 # if defined(__ICL) || defined (__INTEL_COMPILER)
62 # define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:1478))
63 # define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
64 # elif defined(_MSC_VER)
65 # define FF_DISABLE_DEPRECATION_WARNINGS __pragma(warning(push)) __pragma(warning(disable:4996))
66 # define FF_ENABLE_DEPRECATION_WARNINGS __pragma(warning(pop))
67 # else
68 # define FF_DISABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic push") _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
69 # define FF_ENABLE_DEPRECATION_WARNINGS _Pragma("GCC diagnostic pop")
70 # endif
71 #else
72 # define FF_DISABLE_DEPRECATION_WARNINGS
73 # define FF_ENABLE_DEPRECATION_WARNINGS
74 #endif
75 
76 
77 #define FF_MEMORY_POISON 0x2a
78 
79 /* Check if the hard coded offset of a struct member still matches reality.
80  * Induce a compilation failure if not.
81  */
82 #define AV_CHECK_OFFSET(s, m, o) struct check_##o { \
83  int x_##o[offsetof(s, m) == o? 1: -1]; \
84  }
85 
86 
87 #define FF_ALLOC_TYPED_ARRAY(p, nelem) (p = av_malloc_array(nelem, sizeof(*p)))
88 #define FF_ALLOCZ_TYPED_ARRAY(p, nelem) (p = av_calloc(nelem, sizeof(*p)))
89 
90 #define FF_PTR_ADD(ptr, off) ((off) ? (ptr) + (off) : (ptr))
91 
92 /**
93  * Access a field in a structure by its offset.
94  */
95 #define FF_FIELD_AT(type, off, obj) (*(type *)((char *)&(obj) + (off)))
96 
97 #include "libm.h"
98 
99 /**
100  * Return NULL if CONFIG_SMALL is true, otherwise the argument
101  * without modification. Used to disable the definition of strings.
102  */
103 #if CONFIG_SMALL
104 # define NULL_IF_CONFIG_SMALL(x) NULL
105 #else
106 # define NULL_IF_CONFIG_SMALL(x) x
107 #endif
108 
109 /**
110  * Log a generic warning message about a missing feature.
111  *
112  * @param[in] avc a pointer to an arbitrary struct of which the first
113  * field is a pointer to an AVClass struct
114  * @param[in] msg string containing the name of the missing feature
115  */
116 void avpriv_report_missing_feature(void *avc,
117  const char *msg, ...) av_printf_format(2, 3);
118 
119 /**
120  * Log a generic warning message about a missing feature.
121  * Additionally request that a sample showcasing the feature be uploaded.
122  *
123  * @param[in] avc a pointer to an arbitrary struct of which the first field is
124  * a pointer to an AVClass struct
125  * @param[in] msg string containing the name of the missing feature
126  */
127 void avpriv_request_sample(void *avc,
128  const char *msg, ...) av_printf_format(2, 3);
129 
130 #if HAVE_LIBC_MSVCRT
131 #include <crtversion.h>
132 #if defined(_VC_CRT_MAJOR_VERSION) && _VC_CRT_MAJOR_VERSION < 14
133 #pragma comment(linker, "/include:" EXTERN_PREFIX "avpriv_strtod")
134 #pragma comment(linker, "/include:" EXTERN_PREFIX "avpriv_snprintf")
135 #endif
136 
137 #define PTRDIFF_SPECIFIER "Id"
138 #define SIZE_SPECIFIER "Iu"
139 #else
140 #define PTRDIFF_SPECIFIER "td"
141 #define SIZE_SPECIFIER "zu"
142 #endif
143 
144 #ifdef DEBUG
145 # define ff_dlog(ctx, ...) av_log(ctx, AV_LOG_DEBUG, __VA_ARGS__)
146 #else
147 # define ff_dlog(ctx, ...) do { if (0) av_log(ctx, AV_LOG_DEBUG, __VA_ARGS__); } while (0)
148 #endif
149 
150 #ifdef TRACE
151 # define ff_tlog(ctx, ...) av_log(ctx, AV_LOG_TRACE, __VA_ARGS__)
152 #else
153 # define ff_tlog(ctx, ...) do { } while(0)
154 #endif
155 
156 // For debuging we use signed operations so overflows can be detected (by ubsan)
157 // For production we use unsigned so there are no undefined operations
158 #ifdef CHECKED
159 #define SUINT int
160 #define SUINT32 int32_t
161 #else
162 #define SUINT unsigned
163 #define SUINT32 uint32_t
164 #endif
165 
166 int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt);
167 
168 static av_always_inline av_const int avpriv_mirror(int x, int w)
169 {
170  if (!w)
171  return 0;
172 
173  while ((unsigned)x > (unsigned)w) {
174  x = -x;
175  if (x < 0)
176  x += 2 * w;
177  }
178  return x;
179 }
180 
181 #endif /* AVUTIL_INTERNAL_H */
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:71
libm.h
avpriv_set_systematic_pal2
int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt)
Definition: imgutils.c:178
w
uint8_t w
Definition: llviddspenc.c:38
av_const
#define av_const
Definition: attributes.h:84
macros.h
pix_fmt
static enum AVPixelFormat pix_fmt
Definition: demux_decode.c:41
limits.h
avpriv_request_sample
void void avpriv_request_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
av_printf_format
#define av_printf_format(fmtpos, attrpos)
Definition: attributes.h:161
avpriv_mirror
static av_always_inline av_const int avpriv_mirror(int x, int w)
Definition: internal.h:168
avpriv_report_missing_feature
void avpriv_report_missing_feature(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
attributes.h
av_always_inline
#define av_always_inline
Definition: attributes.h:49
pixfmt.h