FFmpeg
options.c
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1 /*
2  * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
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 #include "avformat.h"
21 #include "avio_internal.h"
22 #include "internal.h"
23 
24 #include "libavutil/avassert.h"
25 #include "libavutil/internal.h"
26 #include "libavutil/opt.h"
27 
28 /**
29  * @file
30  * Options definition for AVFormatContext.
31  */
32 
34 #include "options_table.h"
36 
37 static const char* format_to_name(void* ptr)
38 {
40  if(fc->iformat) return fc->iformat->name;
41  else if(fc->oformat) return fc->oformat->name;
42  else return "NULL";
43 }
44 
45 static void *format_child_next(void *obj, void *prev)
46 {
47  AVFormatContext *s = obj;
48  if (!prev && s->priv_data &&
49  ((s->iformat && s->iformat->priv_class) ||
50  s->oformat && s->oformat->priv_class))
51  return s->priv_data;
52  if (s->pb && s->pb->av_class && prev != s->pb)
53  return s->pb;
54  return NULL;
55 }
56 
57 #if FF_API_CHILD_CLASS_NEXT
59 static const AVClass *format_child_class_next(const AVClass *prev)
60 {
61  AVInputFormat *ifmt = NULL;
62  AVOutputFormat *ofmt = NULL;
63 
64  if (!prev)
65  return &ff_avio_class;
66 
67  while ((ifmt = av_iformat_next(ifmt)))
68  if (ifmt->priv_class == prev)
69  break;
70 
71  if (!ifmt)
72  while ((ofmt = av_oformat_next(ofmt)))
73  if (ofmt->priv_class == prev)
74  break;
75  if (!ofmt)
76  while (ifmt = av_iformat_next(ifmt))
77  if (ifmt->priv_class)
78  return ifmt->priv_class;
79 
80  while (ofmt = av_oformat_next(ofmt))
81  if (ofmt->priv_class)
82  return ofmt->priv_class;
83 
84  return NULL;
85 }
87 #endif
88 
89 enum {
94 
95 };
96 
97 #define ITER_STATE_SHIFT 16
98 
99 static const AVClass *format_child_class_iterate(void **iter)
100 {
101  // we use the low 16 bits of iter as the value to be passed to
102  // av_(de)muxer_iterate()
103  void *val = (void*)(((uintptr_t)*iter) & ((1 << ITER_STATE_SHIFT) - 1));
104  unsigned int state = ((uintptr_t)*iter) >> ITER_STATE_SHIFT;
105  const AVClass *ret = NULL;
106 
107  if (state == CHILD_CLASS_ITER_AVIO) {
108  ret = &ff_avio_class;
109  state++;
110  goto finish;
111  }
112 
113  if (state == CHILD_CLASS_ITER_MUX) {
114  const AVOutputFormat *ofmt;
115 
116  while ((ofmt = av_muxer_iterate(&val))) {
117  ret = ofmt->priv_class;
118  if (ret)
119  goto finish;
120  }
121 
122  val = NULL;
123  state++;
124  }
125 
126  if (state == CHILD_CLASS_ITER_DEMUX) {
127  const AVInputFormat *ifmt;
128 
129  while ((ifmt = av_demuxer_iterate(&val))) {
130  ret = ifmt->priv_class;
131  if (ret)
132  goto finish;
133  }
134  val = NULL;
135  state++;
136  }
137 
138 finish:
139  // make sure none av_(de)muxer_iterate does not set the high bits of val
140  av_assert0(!((uintptr_t)val >> ITER_STATE_SHIFT));
141  *iter = (void*)((uintptr_t)val | (state << ITER_STATE_SHIFT));
142  return ret;
143 }
144 
145 static AVClassCategory get_category(void *ptr)
146 {
147  AVFormatContext* s = ptr;
148  if(s->iformat) return AV_CLASS_CATEGORY_DEMUXER;
149  else return AV_CLASS_CATEGORY_MUXER;
150 }
151 
153  .class_name = "AVFormatContext",
154  .item_name = format_to_name,
155  .option = avformat_options,
156  .version = LIBAVUTIL_VERSION_INT,
157  .child_next = format_child_next,
158 #if FF_API_CHILD_CLASS_NEXT
159  .child_class_next = format_child_class_next,
160 #endif
161  .child_class_iterate = format_child_class_iterate,
163  .get_category = get_category,
164 };
165 
167  const char *url, int flags, AVDictionary **options)
168 {
169  int loglevel;
170 
171  if (!strcmp(url, s->url) ||
172  s->iformat && !strcmp(s->iformat->name, "image2") ||
173  s->oformat && !strcmp(s->oformat->name, "image2")
174  ) {
175  loglevel = AV_LOG_DEBUG;
176  } else
177  loglevel = AV_LOG_INFO;
178 
179  av_log(s, loglevel, "Opening \'%s\' for %s\n", url, flags & AVIO_FLAG_WRITE ? "writing" : "reading");
180 
181 #if FF_API_OLD_OPEN_CALLBACKS
183  if (s->open_cb)
184  return s->open_cb(s, pb, url, flags, &s->interrupt_callback, options);
186 #endif
187 
188  return ffio_open_whitelist(pb, url, flags, &s->interrupt_callback, options, s->protocol_whitelist, s->protocol_blacklist);
189 }
190 
192 {
193  avio_close(pb);
194 }
195 
197 {
198  memset(s, 0, sizeof(AVFormatContext));
199 
201 
204 
206 }
207 
209 {
210  AVFormatContext *ic;
211  AVFormatInternal *internal;
212  ic = av_malloc(sizeof(AVFormatContext));
213  if (!ic) return ic;
214 
215  internal = av_mallocz(sizeof(*internal));
216  if (!internal) {
217  av_free(ic);
218  return NULL;
219  }
221  ic->internal = internal;
225 
226  return ic;
227 }
228 
230 {
231  return ctx->duration_estimation_method;
232 }
233 
235 {
236  return &av_format_context_class;
237 }
int(* io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags, AVDictionary **options)
A callback for opening new IO streams.
Definition: avformat.h:1933
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:161
static const AVClass av_format_context_class
Definition: options.c:152
AVIOInterruptCB interrupt_callback
Custom interrupt callbacks for the I/O layer.
Definition: avformat.h:1629
enum AVDurationEstimationMethod duration_estimation_method
The duration field can be estimated through various ways, and this field can be used to know how the ...
Definition: avformat.h:1738
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
void av_opt_set_defaults(void *s)
Set the values of all AVOption fields to their default values.
Definition: opt.c:1357
AVFormatInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1804
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:675
enum AVDurationEstimationMethod av_fmt_ctx_get_duration_estimation_method(const AVFormatContext *ctx)
Returns the method used to set ctx->duration.
Definition: options.c:229
int64_t offset
Offset to remap timestamps to be non-negative.
Definition: internal.h:106
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:237
static struct @315 state
Format I/O context.
Definition: avformat.h:1351
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
#define ITER_STATE_SHIFT
Definition: options.c:97
static const AVClass * format_child_class_iterate(void **iter)
Definition: options.c:99
#define av_malloc(s)
AVOptions.
static void io_close_default(AVFormatContext *s, AVIOContext *pb)
Definition: options.c:191
AVDurationEstimationMethod
The duration of a video can be estimated through various ways, and this enum can be used to know how ...
Definition: avformat.h:1329
static void avformat_get_context_defaults(AVFormatContext *s)
Definition: options.c:196
const AVClass * av_class
A class for private options.
Definition: avio.h:174
AVFormatContext * avformat_alloc_context(void)
Allocate an AVFormatContext.
Definition: options.c:208
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:675
static void finish(void)
Definition: movenc.c:345
static AVClassCategory get_category(void *ptr)
Definition: options.c:145
char * protocol_whitelist
&#39;,&#39; separated list of allowed protocols.
Definition: avformat.h:1911
const AVClass ff_avio_class
Definition: aviobuf.c:73
const AVClass * avformat_get_class(void)
Get the AVClass for AVFormatContext.
Definition: options.c:234
int raw_packet_buffer_remaining_size
Definition: internal.h:99
#define av_log(a,...)
const AVOutputFormat * av_muxer_iterate(void **opaque)
Iterate over all registered muxers.
Definition: allformats.c:518
#define fc(width, name, range_min, range_max)
Definition: cbs_av1.c:550
int avio_close(AVIOContext *s)
Close the resource accessed by the AVIOContext s and free it.
Definition: aviobuf.c:1159
ff_const59 struct AVInputFormat * iformat
The input container format.
Definition: avformat.h:1363
char * url
input or output URL.
Definition: avformat.h:1447
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:215
static const AVOption avformat_options[]
Definition: options_table.h:36
simple assert() macros that are a bit more flexible than ISO C assert().
AVClassCategory category
Category used for visualization (like color) This is only set if the category is equal for all object...
Definition: log.h:133
common internal API header
int64_t shortest_end
Timestamp of the end of the shortest stream.
Definition: internal.h:124
const char * name
Definition: avformat.h:500
AVFormatContext * ctx
Definition: movenc.c:48
#define s(width, name)
Definition: cbs_vp9.c:257
static const AVOption options[]
Definition: options.c:37
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:528
const AVInputFormat * av_demuxer_iterate(void **opaque)
Iterate over all registered demuxers.
Definition: allformats.c:535
ff_const59 struct AVOutputFormat * oformat
The output container format.
Definition: avformat.h:1370
#define AV_LOG_INFO
Standard information.
Definition: log.h:205
AVIOContext * pb
I/O context.
Definition: avformat.h:1393
void(* io_close)(struct AVFormatContext *s, AVIOContext *pb)
A callback for closing the streams opened with AVFormatContext.io_open().
Definition: avformat.h:1939
Describe the class of an AVClass context structure.
Definition: log.h:67
static void * format_child_next(void *obj, void *prev)
Definition: options.c:45
const AVClass * av_class
A class for logging and AVOptions.
Definition: avformat.h:1356
#define RAW_PACKET_BUFFER_SIZE
Remaining size available for raw_packet_buffer, in bytes.
Definition: internal.h:98
int ffio_open_whitelist(AVIOContext **s, const char *url, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options, const char *whitelist, const char *blacklist)
Definition: aviobuf.c:1132
#define flags(name, subs,...)
Definition: cbs_av1.c:560
Main libavformat public API header.
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:84
FF_DISABLE_DEPRECATION_WARNINGS static FF_ENABLE_DEPRECATION_WARNINGS const char * format_to_name(void *ptr)
Definition: options.c:37
#define av_free(p)
AVClassCategory
Definition: log.h:29
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:85
void * priv_data
Format private data.
Definition: avformat.h:1379
char * protocol_blacklist
&#39;,&#39; separated list of disallowed protocols.
Definition: avformat.h:1946
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:650
static int io_open_default(AVFormatContext *s, AVIOContext **pb, const char *url, int flags, AVDictionary **options)
Definition: options.c:166
static double val(void *priv, double ch)
Definition: aeval.c:76
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248