FFmpeg  1.2.12
aviobuf.c
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1 /*
2  * buffered I/O
3  * Copyright (c) 2000,2001 Fabrice Bellard
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/crc.h"
23 #include "libavutil/dict.h"
24 #include "libavutil/intreadwrite.h"
25 #include "libavutil/log.h"
26 #include "libavutil/opt.h"
27 #include "libavutil/avassert.h"
28 #include "avformat.h"
29 #include "avio.h"
30 #include "avio_internal.h"
31 #include "internal.h"
32 #include "url.h"
33 #include <stdarg.h>
34 
35 #define IO_BUFFER_SIZE 32768
36 
42 #define SHORT_SEEK_THRESHOLD 4096
43 
44 static void *ffio_url_child_next(void *obj, void *prev)
45 {
46  AVIOContext *s = obj;
47  return prev ? NULL : s->opaque;
48 }
49 
50 static const AVClass *ffio_url_child_class_next(const AVClass *prev)
51 {
52  return prev ? NULL : &ffurl_context_class;
53 }
54 
55 static const AVOption ffio_url_options[] = {
56  { NULL },
57 };
58 
60  .class_name = "AVIOContext",
61  .item_name = av_default_item_name,
62  .version = LIBAVUTIL_VERSION_INT,
63  .option = ffio_url_options,
64  .child_next = ffio_url_child_next,
65  .child_class_next = ffio_url_child_class_next,
66 };
67 
68 static void fill_buffer(AVIOContext *s);
69 static int url_resetbuf(AVIOContext *s, int flags);
70 
72  unsigned char *buffer,
73  int buffer_size,
74  int write_flag,
75  void *opaque,
76  int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
77  int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
78  int64_t (*seek)(void *opaque, int64_t offset, int whence))
79 {
80  s->buffer = buffer;
81  s->buffer_size = buffer_size;
82  s->buf_ptr = buffer;
83  s->opaque = opaque;
84  s->direct = 0;
85 
86  url_resetbuf(s, write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
87 
90  s->seek = seek;
91  s->pos = 0;
92  s->must_flush = 0;
93  s->eof_reached = 0;
94  s->error = 0;
96  s->max_packet_size = 0;
97  s->update_checksum = NULL;
98 
99  if (!read_packet && !write_flag) {
100  s->pos = buffer_size;
101  s->buf_end = s->buffer + buffer_size;
102  }
103  s->read_pause = NULL;
104  s->read_seek = NULL;
105 
106  return 0;
107 }
108 
110  unsigned char *buffer,
111  int buffer_size,
112  int write_flag,
113  void *opaque,
114  int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
115  int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
116  int64_t (*seek)(void *opaque, int64_t offset, int whence))
117 {
118  AVIOContext *s = av_mallocz(sizeof(AVIOContext));
119  if (!s)
120  return NULL;
121  ffio_init_context(s, buffer, buffer_size, write_flag, opaque,
122  read_packet, write_packet, seek);
123  return s;
124 }
125 
126 static void writeout(AVIOContext *s, const uint8_t *data, int len)
127 {
128  if (s->write_packet && !s->error) {
129  int ret = s->write_packet(s->opaque, (uint8_t *)data, len);
130  if (ret < 0) {
131  s->error = ret;
132  }
133  }
134  s->pos += len;
135 }
136 
137 static void flush_buffer(AVIOContext *s)
138 {
139  if (s->buf_ptr > s->buffer) {
140  writeout(s, s->buffer, s->buf_ptr - s->buffer);
141  if (s->update_checksum) {
143  s->buf_ptr - s->checksum_ptr);
144  s->checksum_ptr = s->buffer;
145  }
146  }
147  s->buf_ptr = s->buffer;
148 }
149 
150 void avio_w8(AVIOContext *s, int b)
151 {
152  av_assert2(b>=-128 && b<=255);
153  *s->buf_ptr++ = b;
154  if (s->buf_ptr >= s->buf_end)
155  flush_buffer(s);
156 }
157 
158 void ffio_fill(AVIOContext *s, int b, int count)
159 {
160  while (count > 0) {
161  int len = FFMIN(s->buf_end - s->buf_ptr, count);
162  memset(s->buf_ptr, b, len);
163  s->buf_ptr += len;
164 
165  if (s->buf_ptr >= s->buf_end)
166  flush_buffer(s);
167 
168  count -= len;
169  }
170 }
171 
172 void avio_write(AVIOContext *s, const unsigned char *buf, int size)
173 {
174  if (s->direct && !s->update_checksum) {
175  avio_flush(s);
176  writeout(s, buf, size);
177  return;
178  }
179  while (size > 0) {
180  int len = FFMIN(s->buf_end - s->buf_ptr, size);
181  memcpy(s->buf_ptr, buf, len);
182  s->buf_ptr += len;
183 
184  if (s->buf_ptr >= s->buf_end)
185  flush_buffer(s);
186 
187  buf += len;
188  size -= len;
189  }
190 }
191 
193 {
194  flush_buffer(s);
195  s->must_flush = 0;
196 }
197 
198 int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
199 {
200  int64_t offset1;
201  int64_t pos;
202  int force = whence & AVSEEK_FORCE;
203  whence &= ~AVSEEK_FORCE;
204 
205  if(!s)
206  return AVERROR(EINVAL);
207 
208  pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
209 
210  if (whence != SEEK_CUR && whence != SEEK_SET)
211  return AVERROR(EINVAL);
212 
213  if (whence == SEEK_CUR) {
214  offset1 = pos + (s->buf_ptr - s->buffer);
215  if (offset == 0)
216  return offset1;
217  offset += offset1;
218  }
219  if (offset < 0)
220  return AVERROR(EINVAL);
221 
222  offset1 = offset - pos;
223  if (!s->must_flush && (!s->direct || !s->seek) &&
224  offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
225  /* can do the seek inside the buffer */
226  s->buf_ptr = s->buffer + offset1;
227  } else if ((!s->seekable ||
228  offset1 <= s->buf_end + SHORT_SEEK_THRESHOLD - s->buffer) &&
229  !s->write_flag && offset1 >= 0 &&
230  (!s->direct || !s->seek) &&
231  (whence != SEEK_END || force)) {
232  while(s->pos < offset && !s->eof_reached)
233  fill_buffer(s);
234  if (s->eof_reached)
235  return AVERROR_EOF;
236  s->buf_ptr = s->buf_end + offset - s->pos;
237  } else {
238  int64_t res;
239 
240  if (s->write_flag) {
241  flush_buffer(s);
242  s->must_flush = 1;
243  }
244  if (!s->seek)
245  return AVERROR(EPIPE);
246  if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
247  return res;
248  s->seek_count ++;
249  if (!s->write_flag)
250  s->buf_end = s->buffer;
251  s->buf_ptr = s->buffer;
252  s->pos = offset;
253  }
254  s->eof_reached = 0;
255  return offset;
256 }
257 
258 int64_t avio_skip(AVIOContext *s, int64_t offset)
259 {
260  return avio_seek(s, offset, SEEK_CUR);
261 }
262 
264 {
265  int64_t size;
266 
267  if (!s)
268  return AVERROR(EINVAL);
269 
270  if (!s->seek)
271  return AVERROR(ENOSYS);
272  size = s->seek(s->opaque, 0, AVSEEK_SIZE);
273  if (size < 0) {
274  if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
275  return size;
276  size++;
277  s->seek(s->opaque, s->pos, SEEK_SET);
278  }
279  return size;
280 }
281 
283 {
284  if(!s)
285  return 0;
286  if(s->eof_reached){
287  s->eof_reached=0;
288  fill_buffer(s);
289  }
290  return s->eof_reached;
291 }
292 
293 void avio_wl32(AVIOContext *s, unsigned int val)
294 {
295  avio_w8(s, (uint8_t) val );
296  avio_w8(s, (uint8_t)(val >> 8 ));
297  avio_w8(s, (uint8_t)(val >> 16));
298  avio_w8(s, val >> 24 );
299 }
300 
301 void avio_wb32(AVIOContext *s, unsigned int val)
302 {
303  avio_w8(s, val >> 24 );
304  avio_w8(s, (uint8_t)(val >> 16));
305  avio_w8(s, (uint8_t)(val >> 8 ));
306  avio_w8(s, (uint8_t) val );
307 }
308 
309 int avio_put_str(AVIOContext *s, const char *str)
310 {
311  int len = 1;
312  if (str) {
313  len += strlen(str);
314  avio_write(s, (const unsigned char *) str, len);
315  } else
316  avio_w8(s, 0);
317  return len;
318 }
319 
320 int avio_put_str16le(AVIOContext *s, const char *str)
321 {
322  const uint8_t *q = str;
323  int ret = 0;
324 
325  while (*q) {
326  uint32_t ch;
327  uint16_t tmp;
328 
329  GET_UTF8(ch, *q++, break;)
330  PUT_UTF16(ch, tmp, avio_wl16(s, tmp); ret += 2;)
331  }
332  avio_wl16(s, 0);
333  ret += 2;
334  return ret;
335 }
336 
337 int ff_get_v_length(uint64_t val)
338 {
339  int i = 1;
340 
341  while (val >>= 7)
342  i++;
343 
344  return i;
345 }
346 
347 void ff_put_v(AVIOContext *bc, uint64_t val)
348 {
349  int i = ff_get_v_length(val);
350 
351  while (--i > 0)
352  avio_w8(bc, 128 | (uint8_t)(val >> (7*i)));
353 
354  avio_w8(bc, val & 127);
355 }
356 
357 void avio_wl64(AVIOContext *s, uint64_t val)
358 {
359  avio_wl32(s, (uint32_t)(val & 0xffffffff));
360  avio_wl32(s, (uint32_t)(val >> 32));
361 }
362 
363 void avio_wb64(AVIOContext *s, uint64_t val)
364 {
365  avio_wb32(s, (uint32_t)(val >> 32));
366  avio_wb32(s, (uint32_t)(val & 0xffffffff));
367 }
368 
369 void avio_wl16(AVIOContext *s, unsigned int val)
370 {
371  avio_w8(s, (uint8_t)val);
372  avio_w8(s, (int)val >> 8);
373 }
374 
375 void avio_wb16(AVIOContext *s, unsigned int val)
376 {
377  avio_w8(s, (int)val >> 8);
378  avio_w8(s, (uint8_t)val);
379 }
380 
381 void avio_wl24(AVIOContext *s, unsigned int val)
382 {
383  avio_wl16(s, val & 0xffff);
384  avio_w8(s, (int)val >> 16);
385 }
386 
387 void avio_wb24(AVIOContext *s, unsigned int val)
388 {
389  avio_wb16(s, (int)val >> 8);
390  avio_w8(s, (uint8_t)val);
391 }
392 
393 /* Input stream */
394 
395 static void fill_buffer(AVIOContext *s)
396 {
397  uint8_t *dst = !s->max_packet_size &&
398  s->buf_end - s->buffer < s->buffer_size ?
399  s->buf_end : s->buffer;
400  int len = s->buffer_size - (dst - s->buffer);
401  int max_buffer_size = s->max_packet_size ?
403 
404  /* can't fill the buffer without read_packet, just set EOF if appropriate */
405  if (!s->read_packet && s->buf_ptr >= s->buf_end)
406  s->eof_reached = 1;
407 
408  /* no need to do anything if EOF already reached */
409  if (s->eof_reached)
410  return;
411 
412  if (s->update_checksum && dst == s->buffer) {
413  if (s->buf_end > s->checksum_ptr)
415  s->buf_end - s->checksum_ptr);
416  s->checksum_ptr = s->buffer;
417  }
418 
419  /* make buffer smaller in case it ended up large after probing */
420  if (s->read_packet && s->buffer_size > max_buffer_size) {
421  ffio_set_buf_size(s, max_buffer_size);
422 
423  s->checksum_ptr = dst = s->buffer;
424  len = s->buffer_size;
425  }
426 
427  if (s->read_packet)
428  len = s->read_packet(s->opaque, dst, len);
429  else
430  len = 0;
431  if (len <= 0) {
432  /* do not modify buffer if EOF reached so that a seek back can
433  be done without rereading data */
434  s->eof_reached = 1;
435  if (len < 0)
436  s->error = len;
437  } else {
438  s->pos += len;
439  s->buf_ptr = dst;
440  s->buf_end = dst + len;
441  s->bytes_read += len;
442  }
443 }
444 
445 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
446  unsigned int len)
447 {
448  return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
449 }
450 
452 {
454  s->buf_ptr - s->checksum_ptr);
455  s->update_checksum = NULL;
456  return s->checksum;
457 }
458 
460  unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
461  unsigned long checksum)
462 {
463  s->update_checksum = update_checksum;
464  if (s->update_checksum) {
465  s->checksum = checksum;
466  s->checksum_ptr = s->buf_ptr;
467  }
468 }
469 
470 /* XXX: put an inline version */
472 {
473  if (s->buf_ptr >= s->buf_end)
474  fill_buffer(s);
475  if (s->buf_ptr < s->buf_end)
476  return *s->buf_ptr++;
477  return 0;
478 }
479 
480 int avio_read(AVIOContext *s, unsigned char *buf, int size)
481 {
482  int len, size1;
483 
484  size1 = size;
485  while (size > 0) {
486  len = s->buf_end - s->buf_ptr;
487  if (len > size)
488  len = size;
489  if (len == 0 || s->write_flag) {
490  if((s->direct || size > s->buffer_size) && !s->update_checksum){
491  if(s->read_packet)
492  len = s->read_packet(s->opaque, buf, size);
493  if (len <= 0) {
494  /* do not modify buffer if EOF reached so that a seek back can
495  be done without rereading data */
496  s->eof_reached = 1;
497  if(len<0)
498  s->error= len;
499  break;
500  } else {
501  s->pos += len;
502  s->bytes_read += len;
503  size -= len;
504  buf += len;
505  s->buf_ptr = s->buffer;
506  s->buf_end = s->buffer/* + len*/;
507  }
508  } else {
509  fill_buffer(s);
510  len = s->buf_end - s->buf_ptr;
511  if (len == 0)
512  break;
513  }
514  } else {
515  memcpy(buf, s->buf_ptr, len);
516  buf += len;
517  s->buf_ptr += len;
518  size -= len;
519  }
520  }
521  if (size1 == size) {
522  if (s->error) return s->error;
523  if (url_feof(s)) return AVERROR_EOF;
524  }
525  return size1 - size;
526 }
527 
528 int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
529 {
530  int len;
531 
532  if (size < 0)
533  return -1;
534 
535  if (s->read_packet && s->write_flag) {
536  len = s->read_packet(s->opaque, buf, size);
537  if (len > 0)
538  s->pos += len;
539  return len;
540  }
541 
542  len = s->buf_end - s->buf_ptr;
543  if (len == 0) {
544  /* Reset the buf_end pointer to the start of the buffer, to make sure
545  * the fill_buffer call tries to read as much data as fits into the
546  * full buffer, instead of just what space is left after buf_end.
547  * This avoids returning partial packets at the end of the buffer,
548  * for packet based inputs.
549  */
550  s->buf_end = s->buf_ptr = s->buffer;
551  fill_buffer(s);
552  len = s->buf_end - s->buf_ptr;
553  }
554  if (len > size)
555  len = size;
556  memcpy(buf, s->buf_ptr, len);
557  s->buf_ptr += len;
558  if (!len) {
559  if (s->error) return s->error;
560  if (url_feof(s)) return AVERROR_EOF;
561  }
562  return len;
563 }
564 
565 unsigned int avio_rl16(AVIOContext *s)
566 {
567  unsigned int val;
568  val = avio_r8(s);
569  val |= avio_r8(s) << 8;
570  return val;
571 }
572 
573 unsigned int avio_rl24(AVIOContext *s)
574 {
575  unsigned int val;
576  val = avio_rl16(s);
577  val |= avio_r8(s) << 16;
578  return val;
579 }
580 
581 unsigned int avio_rl32(AVIOContext *s)
582 {
583  unsigned int val;
584  val = avio_rl16(s);
585  val |= avio_rl16(s) << 16;
586  return val;
587 }
588 
589 uint64_t avio_rl64(AVIOContext *s)
590 {
591  uint64_t val;
592  val = (uint64_t)avio_rl32(s);
593  val |= (uint64_t)avio_rl32(s) << 32;
594  return val;
595 }
596 
597 unsigned int avio_rb16(AVIOContext *s)
598 {
599  unsigned int val;
600  val = avio_r8(s) << 8;
601  val |= avio_r8(s);
602  return val;
603 }
604 
605 unsigned int avio_rb24(AVIOContext *s)
606 {
607  unsigned int val;
608  val = avio_rb16(s) << 8;
609  val |= avio_r8(s);
610  return val;
611 }
612 unsigned int avio_rb32(AVIOContext *s)
613 {
614  unsigned int val;
615  val = avio_rb16(s) << 16;
616  val |= avio_rb16(s);
617  return val;
618 }
619 
620 int ff_get_line(AVIOContext *s, char *buf, int maxlen)
621 {
622  int i = 0;
623  char c;
624 
625  do {
626  c = avio_r8(s);
627  if (c && i < maxlen-1)
628  buf[i++] = c;
629  } while (c != '\n' && c);
630 
631  buf[i] = 0;
632  return i;
633 }
634 
635 int avio_get_str(AVIOContext *s, int maxlen, char *buf, int buflen)
636 {
637  int i;
638 
639  if (buflen <= 0)
640  return AVERROR(EINVAL);
641  // reserve 1 byte for terminating 0
642  buflen = FFMIN(buflen - 1, maxlen);
643  for (i = 0; i < buflen; i++)
644  if (!(buf[i] = avio_r8(s)))
645  return i + 1;
646  buf[i] = 0;
647  for (; i < maxlen; i++)
648  if (!avio_r8(s))
649  return i + 1;
650  return maxlen;
651 }
652 
653 #define GET_STR16(type, read) \
654  int avio_get_str16 ##type(AVIOContext *pb, int maxlen, char *buf, int buflen)\
655 {\
656  char* q = buf;\
657  int ret = 0;\
658  if (buflen <= 0) \
659  return AVERROR(EINVAL); \
660  while (ret + 1 < maxlen) {\
661  uint8_t tmp;\
662  uint32_t ch;\
663  GET_UTF16(ch, (ret += 2) <= maxlen ? read(pb) : 0, break;)\
664  if (!ch)\
665  break;\
666  PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)\
667  }\
668  *q = 0;\
669  return ret;\
670 }\
671 
673 GET_STR16(be, avio_rb16)
674 
675 #undef GET_STR16
676 
677 uint64_t avio_rb64(AVIOContext *s)
678 {
679  uint64_t val;
680  val = (uint64_t)avio_rb32(s) << 32;
681  val |= (uint64_t)avio_rb32(s);
682  return val;
683 }
684 
686  uint64_t val = 0;
687  int tmp;
688 
689  do{
690  tmp = avio_r8(bc);
691  val= (val<<7) + (tmp&127);
692  }while(tmp&128);
693  return val;
694 }
695 
697 {
698  uint8_t *buffer;
699  int buffer_size, max_packet_size;
700 
701  max_packet_size = h->max_packet_size;
702  if (max_packet_size) {
703  buffer_size = max_packet_size; /* no need to bufferize more than one packet */
704  } else {
705  buffer_size = IO_BUFFER_SIZE;
706  }
707  buffer = av_malloc(buffer_size);
708  if (!buffer)
709  return AVERROR(ENOMEM);
710 
711  *s = avio_alloc_context(buffer, buffer_size, h->flags & AVIO_FLAG_WRITE, h,
712  (void*)ffurl_read, (void*)ffurl_write, (void*)ffurl_seek);
713  if (!*s) {
714  av_free(buffer);
715  return AVERROR(ENOMEM);
716  }
717  (*s)->direct = h->flags & AVIO_FLAG_DIRECT;
718  (*s)->seekable = h->is_streamed ? 0 : AVIO_SEEKABLE_NORMAL;
719  (*s)->max_packet_size = max_packet_size;
720  if(h->prot) {
721  (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
722  (*s)->read_seek = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
723  }
724  (*s)->av_class = &ffio_url_class;
725  return 0;
726 }
727 
728 int ffio_set_buf_size(AVIOContext *s, int buf_size)
729 {
730  uint8_t *buffer;
731  buffer = av_malloc(buf_size);
732  if (!buffer)
733  return AVERROR(ENOMEM);
734 
735  av_free(s->buffer);
736  s->buffer = buffer;
737  s->buffer_size = buf_size;
738  s->buf_ptr = buffer;
740  return 0;
741 }
742 
743 static int url_resetbuf(AVIOContext *s, int flags)
744 {
745  av_assert1(flags == AVIO_FLAG_WRITE || flags == AVIO_FLAG_READ);
746 
747  if (flags & AVIO_FLAG_WRITE) {
748  s->buf_end = s->buffer + s->buffer_size;
749  s->write_flag = 1;
750  } else {
751  s->buf_end = s->buffer;
752  s->write_flag = 0;
753  }
754  return 0;
755 }
756 
757 int ffio_rewind_with_probe_data(AVIOContext *s, unsigned char **bufp, int buf_size)
758 {
759  int64_t buffer_start;
760  int buffer_size;
761  int overlap, new_size, alloc_size;
762  uint8_t *buf = *bufp;
763 
764  if (s->write_flag) {
765  av_freep(bufp);
766  return AVERROR(EINVAL);
767  }
768 
769  buffer_size = s->buf_end - s->buffer;
770 
771  /* the buffers must touch or overlap */
772  if ((buffer_start = s->pos - buffer_size) > buf_size) {
773  av_freep(bufp);
774  return AVERROR(EINVAL);
775  }
776 
777  overlap = buf_size - buffer_start;
778  new_size = buf_size + buffer_size - overlap;
779 
780  alloc_size = FFMAX(s->buffer_size, new_size);
781  if (alloc_size > buf_size)
782  if (!(buf = (*bufp) = av_realloc_f(buf, 1, alloc_size)))
783  return AVERROR(ENOMEM);
784 
785  if (new_size > buf_size) {
786  memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
787  buf_size = new_size;
788  }
789 
790  av_free(s->buffer);
791  s->buf_ptr = s->buffer = buf;
792  s->buffer_size = alloc_size;
793  s->pos = buf_size;
794  s->buf_end = s->buf_ptr + buf_size;
795  s->eof_reached = 0;
796  s->must_flush = 0;
797 
798  return 0;
799 }
800 
801 int avio_open(AVIOContext **s, const char *filename, int flags)
802 {
803  return avio_open2(s, filename, flags, NULL, NULL);
804 }
805 
806 int avio_open2(AVIOContext **s, const char *filename, int flags,
808 {
809  URLContext *h;
810  int err;
811 
812  err = ffurl_open(&h, filename, flags, int_cb, options);
813  if (err < 0)
814  return err;
815  err = ffio_fdopen(s, h);
816  if (err < 0) {
817  ffurl_close(h);
818  return err;
819  }
820  return 0;
821 }
822 
824 {
825  URLContext *h;
826 
827  if (!s)
828  return 0;
829 
830  avio_flush(s);
831  h = s->opaque;
832  av_freep(&s->buffer);
833  if (!s->write_flag)
834  av_log(s, AV_LOG_DEBUG, "Statistics: %"PRId64" bytes read, %d seeks\n", s->bytes_read, s->seek_count);
835  av_free(s);
836  return ffurl_close(h);
837 }
838 
840 {
841  int ret = avio_close(*s);
842  *s = NULL;
843  return ret;
844 }
845 
846 int avio_printf(AVIOContext *s, const char *fmt, ...)
847 {
848  va_list ap;
849  char buf[4096];
850  int ret;
851 
852  va_start(ap, fmt);
853  ret = vsnprintf(buf, sizeof(buf), fmt, ap);
854  va_end(ap);
855  avio_write(s, buf, strlen(buf));
856  return ret;
857 }
858 
859 int avio_pause(AVIOContext *s, int pause)
860 {
861  if (!s->read_pause)
862  return AVERROR(ENOSYS);
863  return s->read_pause(s->opaque, pause);
864 }
865 
866 int64_t avio_seek_time(AVIOContext *s, int stream_index,
867  int64_t timestamp, int flags)
868 {
869  URLContext *h = s->opaque;
870  int64_t ret;
871  if (!s->read_seek)
872  return AVERROR(ENOSYS);
873  ret = s->read_seek(h, stream_index, timestamp, flags);
874  if (ret >= 0) {
875  int64_t pos;
876  s->buf_ptr = s->buf_end; // Flush buffer
877  pos = s->seek(h, 0, SEEK_CUR);
878  if (pos >= 0)
879  s->pos = pos;
880  else if (pos != AVERROR(ENOSYS))
881  ret = pos;
882  }
883  return ret;
884 }
885 
886 /* output in a dynamic buffer */
887 
888 typedef struct DynBuffer {
893 } DynBuffer;
894 
895 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
896 {
897  DynBuffer *d = opaque;
898  unsigned new_size, new_allocated_size;
899 
900  /* reallocate buffer if needed */
901  new_size = d->pos + buf_size;
902  new_allocated_size = d->allocated_size;
903  if (new_size < d->pos || new_size > INT_MAX/2)
904  return -1;
905  while (new_size > new_allocated_size) {
906  if (!new_allocated_size)
907  new_allocated_size = new_size;
908  else
909  new_allocated_size += new_allocated_size / 2 + 1;
910  }
911 
912  if (new_allocated_size > d->allocated_size) {
913  d->buffer = av_realloc_f(d->buffer, 1, new_allocated_size);
914  if(d->buffer == NULL)
915  return AVERROR(ENOMEM);
916  d->allocated_size = new_allocated_size;
917  }
918  memcpy(d->buffer + d->pos, buf, buf_size);
919  d->pos = new_size;
920  if (d->pos > d->size)
921  d->size = d->pos;
922  return buf_size;
923 }
924 
925 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
926 {
927  unsigned char buf1[4];
928  int ret;
929 
930  /* packetized write: output the header */
931  AV_WB32(buf1, buf_size);
932  ret = dyn_buf_write(opaque, buf1, 4);
933  if (ret < 0)
934  return ret;
935 
936  /* then the data */
937  return dyn_buf_write(opaque, buf, buf_size);
938 }
939 
940 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
941 {
942  DynBuffer *d = opaque;
943 
944  if (whence == SEEK_CUR)
945  offset += d->pos;
946  else if (whence == SEEK_END)
947  offset += d->size;
948  if (offset < 0 || offset > 0x7fffffffLL)
949  return -1;
950  d->pos = offset;
951  return 0;
952 }
953 
954 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
955 {
956  DynBuffer *d;
957  unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
958 
959  if (sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
960  return -1;
961  d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
962  if (!d)
963  return AVERROR(ENOMEM);
964  d->io_buffer_size = io_buffer_size;
965  *s = avio_alloc_context(d->io_buffer, d->io_buffer_size, 1, d, NULL,
966  max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
967  max_packet_size ? NULL : dyn_buf_seek);
968  if(!*s) {
969  av_free(d);
970  return AVERROR(ENOMEM);
971  }
972  (*s)->max_packet_size = max_packet_size;
973  return 0;
974 }
975 
977 {
978  return url_open_dyn_buf_internal(s, 0);
979 }
980 
981 int ffio_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
982 {
983  if (max_packet_size <= 0)
984  return -1;
985  return url_open_dyn_buf_internal(s, max_packet_size);
986 }
987 
989 {
990  DynBuffer *d = s->opaque;
991  int size;
992  static const char padbuf[FF_INPUT_BUFFER_PADDING_SIZE] = {0};
993  int padding = 0;
994 
995  /* don't attempt to pad fixed-size packet buffers */
996  if (!s->max_packet_size) {
997  avio_write(s, padbuf, sizeof(padbuf));
999  }
1000 
1001  avio_flush(s);
1002 
1003  *pbuffer = d->buffer;
1004  size = d->size;
1005  av_free(d);
1006  av_free(s);
1007  return size - padding;
1008 }