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ffmpeg / libavformat / aviobuf.c @ 576ae256

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1
/*
2
 * Buffered I/O for ffmpeg system
3
 * Copyright (c) 2000,2001 Fabrice Bellard
4
 *
5
 * This library is free software; you can redistribute it and/or
6
 * modify it under the terms of the GNU Lesser General Public
7
 * License as published by the Free Software Foundation; either
8
 * version 2 of the License, or (at your option) any later version.
9
 *
10
 * This library is distributed in the hope that it will be useful,
11
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13
 * Lesser General Public License for more details.
14
 *
15
 * You should have received a copy of the GNU Lesser General Public
16
 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18
 */
19
#include "avformat.h"
20
#include "avio.h"
21
#include <stdarg.h>
22

    
23
#define IO_BUFFER_SIZE 32768
24

    
25
int init_put_byte(ByteIOContext *s,
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                  unsigned char *buffer,
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                  int buffer_size,
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                  int write_flag,
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                  void *opaque,
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                  int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
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                  int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
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                  int (*seek)(void *opaque, offset_t offset, int whence))
33
{
34
    s->buffer = buffer;
35
    s->buffer_size = buffer_size;
36
    s->buf_ptr = buffer;
37
    s->write_flag = write_flag;
38
    if (!s->write_flag) 
39
        s->buf_end = buffer;
40
    else
41
        s->buf_end = buffer + buffer_size;
42
    s->opaque = opaque;
43
    s->write_packet = write_packet;
44
    s->read_packet = read_packet;
45
    s->seek = seek;
46
    s->pos = 0;
47
    s->must_flush = 0;
48
    s->eof_reached = 0;
49
    s->error = 0;
50
    s->is_streamed = 0;
51
    s->max_packet_size = 0;
52
    s->update_checksum= NULL;
53
    return 0;
54
}
55
                  
56

    
57
#ifdef CONFIG_ENCODERS
58
static void flush_buffer(ByteIOContext *s)
59
{
60
    if (s->buf_ptr > s->buffer) {
61
        if (s->write_packet && !s->error){
62
            int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
63
            if(ret < 0){
64
                s->error = ret;
65
            }
66
        }
67
        if(s->update_checksum){
68
            s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
69
            s->checksum_ptr= s->buffer;
70
        }
71
        s->pos += s->buf_ptr - s->buffer;
72
    }
73
    s->buf_ptr = s->buffer;
74
}
75

    
76
void put_byte(ByteIOContext *s, int b)
77
{
78
    *(s->buf_ptr)++ = b;
79
    if (s->buf_ptr >= s->buf_end) 
80
        flush_buffer(s);
81
}
82

    
83
void put_buffer(ByteIOContext *s, const unsigned char *buf, int size)
84
{
85
    int len;
86

    
87
    while (size > 0) {
88
        len = (s->buf_end - s->buf_ptr);
89
        if (len > size)
90
            len = size;
91
        memcpy(s->buf_ptr, buf, len);
92
        s->buf_ptr += len;
93

    
94
        if (s->buf_ptr >= s->buf_end) 
95
            flush_buffer(s);
96

    
97
        buf += len;
98
        size -= len;
99
    }
100
}
101

    
102
void put_flush_packet(ByteIOContext *s)
103
{
104
    flush_buffer(s);
105
    s->must_flush = 0;
106
}
107
#endif //CONFIG_ENCODERS
108

    
109
offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence)
110
{
111
    offset_t offset1;
112

    
113
    if (whence != SEEK_CUR && whence != SEEK_SET)
114
        return -EINVAL;
115
    
116
#ifdef CONFIG_ENCODERS
117
    if (s->write_flag) {
118
        if (whence == SEEK_CUR) {
119
            offset1 = s->pos + (s->buf_ptr - s->buffer);
120
            if (offset == 0)
121
                return offset1;
122
            offset += offset1;
123
        }
124
        offset1 = offset - s->pos;
125
        if (!s->must_flush && 
126
            offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) {
127
            /* can do the seek inside the buffer */
128
            s->buf_ptr = s->buffer + offset1;
129
        } else {
130
            if (!s->seek)
131
                return -EPIPE;
132
            flush_buffer(s);
133
            s->must_flush = 1;
134
            s->buf_ptr = s->buffer;
135
            s->seek(s->opaque, offset, SEEK_SET);
136
            s->pos = offset;
137
        }
138
    } else 
139
#endif //CONFIG_ENCODERS
140
    {
141
        if (whence == SEEK_CUR) {
142
            offset1 = s->pos - (s->buf_end - s->buffer) + (s->buf_ptr - s->buffer);
143
            if (offset == 0)
144
                return offset1;
145
            offset += offset1;
146
        }
147
        offset1 = offset - (s->pos - (s->buf_end - s->buffer));
148
        if (offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
149
            /* can do the seek inside the buffer */
150
            s->buf_ptr = s->buffer + offset1;
151
        } else {
152
            if (!s->seek)
153
                return -EPIPE;
154
            s->buf_ptr = s->buffer;
155
            s->buf_end = s->buffer;
156
            if (s->seek(s->opaque, offset, SEEK_SET) == (offset_t)-EPIPE)
157
                return -EPIPE;
158
            s->pos = offset;
159
        }
160
        s->eof_reached = 0;
161
    }
162
    return offset;
163
}
164

    
165
void url_fskip(ByteIOContext *s, offset_t offset)
166
{
167
    url_fseek(s, offset, SEEK_CUR);
168
}
169

    
170
offset_t url_ftell(ByteIOContext *s)
171
{
172
    return url_fseek(s, 0, SEEK_CUR);
173
}
174

    
175
int url_feof(ByteIOContext *s)
176
{
177
    return s->eof_reached;
178
}
179

    
180
int url_ferror(ByteIOContext *s)
181
{
182
    return s->error;
183
}
184

    
185
#ifdef CONFIG_ENCODERS
186
void put_le32(ByteIOContext *s, unsigned int val)
187
{
188
    put_byte(s, val);
189
    put_byte(s, val >> 8);
190
    put_byte(s, val >> 16);
191
    put_byte(s, val >> 24);
192
}
193

    
194
void put_be32(ByteIOContext *s, unsigned int val)
195
{
196
    put_byte(s, val >> 24);
197
    put_byte(s, val >> 16);
198
    put_byte(s, val >> 8);
199
    put_byte(s, val);
200
}
201

    
202
/* IEEE format is assumed */
203
void put_be64_double(ByteIOContext *s, double val)
204
{
205
    union {
206
        double d;
207
        uint64_t ull;
208
    } u;
209
    u.d = val;
210
    put_be64(s, u.ull);
211
}
212

    
213
void put_strz(ByteIOContext *s, const char *str)
214
{
215
    if (str)
216
        put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
217
    else
218
        put_byte(s, 0);
219
}
220

    
221
void put_le64(ByteIOContext *s, uint64_t val)
222
{
223
    put_le32(s, (uint32_t)(val & 0xffffffff));
224
    put_le32(s, (uint32_t)(val >> 32));
225
}
226

    
227
void put_be64(ByteIOContext *s, uint64_t val)
228
{
229
    put_be32(s, (uint32_t)(val >> 32));
230
    put_be32(s, (uint32_t)(val & 0xffffffff));
231
}
232

    
233
void put_le16(ByteIOContext *s, unsigned int val)
234
{
235
    put_byte(s, val);
236
    put_byte(s, val >> 8);
237
}
238

    
239
void put_be16(ByteIOContext *s, unsigned int val)
240
{
241
    put_byte(s, val >> 8);
242
    put_byte(s, val);
243
}
244

    
245
void put_tag(ByteIOContext *s, const char *tag)
246
{
247
    while (*tag) {
248
        put_byte(s, *tag++);
249
    }
250
}
251
#endif //CONFIG_ENCODERS
252

    
253
/* Input stream */
254

    
255
static void fill_buffer(ByteIOContext *s)
256
{
257
    int len;
258

    
259
    /* no need to do anything if EOF already reached */
260
    if (s->eof_reached)
261
        return;
262

    
263
    if(s->update_checksum){
264
        s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
265
        s->checksum_ptr= s->buffer;
266
    }
267

    
268
    len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
269
    if (len <= 0) {
270
        /* do not modify buffer if EOF reached so that a seek back can
271
           be done without rereading data */
272
        s->eof_reached = 1;
273
    if(len<0)
274
        s->error= len;
275
    } else {
276
        s->pos += len;
277
        s->buf_ptr = s->buffer;
278
        s->buf_end = s->buffer + len;
279
    }
280
}
281

    
282
unsigned long get_checksum(ByteIOContext *s){
283
    s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
284
    s->update_checksum= NULL;
285
    return s->checksum;
286
}
287

    
288
void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){
289
    s->update_checksum= update_checksum;
290
    if(s->update_checksum){
291
        s->checksum= s->update_checksum(checksum, NULL, 0);
292
        s->checksum_ptr= s->buf_ptr;
293
    }
294
}
295

    
296
/* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
297
   necessary */
298
/* XXX: put an inline version */
299
int get_byte(ByteIOContext *s)
300
{
301
    if (s->buf_ptr < s->buf_end) {
302
        return *s->buf_ptr++;
303
    } else {
304
        fill_buffer(s);
305
        if (s->buf_ptr < s->buf_end)
306
            return *s->buf_ptr++;
307
        else
308
            return 0;
309
    }
310
}
311

    
312
/* NOTE: return URL_EOF (-1) if EOF */
313
int url_fgetc(ByteIOContext *s)
314
{
315
    if (s->buf_ptr < s->buf_end) {
316
        return *s->buf_ptr++;
317
    } else {
318
        fill_buffer(s);
319
        if (s->buf_ptr < s->buf_end)
320
            return *s->buf_ptr++;
321
        else
322
            return URL_EOF;
323
    }
324
}
325

    
326
int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
327
{
328
    int len, size1;
329

    
330
    size1 = size;
331
    while (size > 0) {
332
        len = s->buf_end - s->buf_ptr;
333
        if (len > size)
334
            len = size;
335
        if (len == 0) {
336
            fill_buffer(s);
337
            len = s->buf_end - s->buf_ptr;
338
            if (len == 0)
339
                break;
340
        } else {
341
            memcpy(buf, s->buf_ptr, len);
342
            buf += len;
343
            s->buf_ptr += len;
344
            size -= len;
345
        }
346
    }
347
    return size1 - size;
348
}
349

    
350
int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
351
{
352
    int len;
353

    
354
    len = s->buf_end - s->buf_ptr;
355
    if (len == 0) {
356
        fill_buffer(s);
357
        len = s->buf_end - s->buf_ptr;
358
    }
359
    if (len > size)
360
        len = size;
361
    memcpy(buf, s->buf_ptr, len);
362
    s->buf_ptr += len;
363
    return len;
364
}
365

    
366
unsigned int get_le16(ByteIOContext *s)
367
{
368
    unsigned int val;
369
    val = get_byte(s);
370
    val |= get_byte(s) << 8;
371
    return val;
372
}
373

    
374
unsigned int get_le32(ByteIOContext *s)
375
{
376
    unsigned int val;
377
    val = get_byte(s);
378
    val |= get_byte(s) << 8;
379
    val |= get_byte(s) << 16;
380
    val |= get_byte(s) << 24;
381
    return val;
382
}
383

    
384
uint64_t get_le64(ByteIOContext *s)
385
{
386
    uint64_t val;
387
    val = (uint64_t)get_le32(s);
388
    val |= (uint64_t)get_le32(s) << 32;
389
    return val;
390
}
391

    
392
unsigned int get_be16(ByteIOContext *s)
393
{
394
    unsigned int val;
395
    val = get_byte(s) << 8;
396
    val |= get_byte(s);
397
    return val;
398
}
399

    
400
unsigned int get_be32(ByteIOContext *s)
401
{
402
    unsigned int val;
403
    val = get_byte(s) << 24;
404
    val |= get_byte(s) << 16;
405
    val |= get_byte(s) << 8;
406
    val |= get_byte(s);
407
    return val;
408
}
409

    
410
double get_be64_double(ByteIOContext *s)
411
{
412
    union {
413
        double d;
414
        uint64_t ull;
415
    } u;
416

    
417
    u.ull = get_be64(s);
418
    return u.d;
419
}
420

    
421
char *get_strz(ByteIOContext *s, char *buf, int maxlen)
422
{
423
    int i = 0;
424
    char c;
425

    
426
    while ((c = get_byte(s))) {
427
        if (i < maxlen-1)
428
            buf[i++] = c;
429
    }
430
    
431
    buf[i] = 0; /* Ensure null terminated, but may be truncated */
432

    
433
    return buf;
434
}
435

    
436
uint64_t get_be64(ByteIOContext *s)
437
{
438
    uint64_t val;
439
    val = (uint64_t)get_be32(s) << 32;
440
    val |= (uint64_t)get_be32(s);
441
    return val;
442
}
443

    
444
/* link with avio functions */
445

    
446
#ifdef CONFIG_ENCODERS
447
static int url_write_packet(void *opaque, uint8_t *buf, int buf_size)
448
{
449
    URLContext *h = opaque;
450
    return url_write(h, buf, buf_size);
451
}
452
#else
453
#define        url_write_packet NULL
454
#endif //CONFIG_ENCODERS
455

    
456
static int url_read_packet(void *opaque, uint8_t *buf, int buf_size)
457
{
458
    URLContext *h = opaque;
459
    return url_read(h, buf, buf_size);
460
}
461

    
462
static int url_seek_packet(void *opaque, int64_t offset, int whence)
463
{
464
    URLContext *h = opaque;
465
    return url_seek(h, offset, whence);
466
    //return 0;
467
}
468

    
469
int url_fdopen(ByteIOContext *s, URLContext *h)
470
{
471
    uint8_t *buffer;
472
    int buffer_size, max_packet_size;
473

    
474
    
475
    max_packet_size = url_get_max_packet_size(h);
476
    if (max_packet_size) {
477
        buffer_size = max_packet_size; /* no need to bufferize more than one packet */
478
    } else {
479
        buffer_size = IO_BUFFER_SIZE;
480
    }
481
    buffer = av_malloc(buffer_size);
482
    if (!buffer)
483
        return -ENOMEM;
484

    
485
    if (init_put_byte(s, buffer, buffer_size, 
486
                      (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
487
                      url_read_packet, url_write_packet, url_seek_packet) < 0) {
488
        av_free(buffer);
489
        return AVERROR_IO;
490
    }
491
    s->is_streamed = h->is_streamed;
492
    s->max_packet_size = max_packet_size;
493
    return 0;
494
}
495

    
496
/* XXX: must be called before any I/O */
497
int url_setbufsize(ByteIOContext *s, int buf_size)
498
{
499
    uint8_t *buffer;
500
    buffer = av_malloc(buf_size);
501
    if (!buffer)
502
        return -ENOMEM;
503

    
504
    av_free(s->buffer);
505
    s->buffer = buffer;
506
    s->buffer_size = buf_size;
507
    s->buf_ptr = buffer;
508
    if (!s->write_flag) 
509
        s->buf_end = buffer;
510
    else
511
        s->buf_end = buffer + buf_size;
512
    return 0;
513
}
514

    
515
/* NOTE: when opened as read/write, the buffers are only used for
516
   reading */
517
int url_fopen(ByteIOContext *s, const char *filename, int flags)
518
{
519
    URLContext *h;
520
    int err;
521

    
522
    err = url_open(&h, filename, flags);
523
    if (err < 0)
524
        return err;
525
    err = url_fdopen(s, h);
526
    if (err < 0) {
527
        url_close(h);
528
        return err;
529
    }
530
    return 0;
531
}
532

    
533
int url_fclose(ByteIOContext *s)
534
{
535
    URLContext *h = s->opaque;
536
    
537
    av_free(s->buffer);
538
    memset(s, 0, sizeof(ByteIOContext));
539
    return url_close(h);
540
}
541

    
542
URLContext *url_fileno(ByteIOContext *s)
543
{
544
    return s->opaque;
545
}
546

    
547
#ifdef CONFIG_ENCODERS
548
/* XXX: currently size is limited */
549
int url_fprintf(ByteIOContext *s, const char *fmt, ...)
550
{
551
    va_list ap;
552
    char buf[4096];
553
    int ret;
554

    
555
    va_start(ap, fmt);
556
    ret = vsnprintf(buf, sizeof(buf), fmt, ap);
557
    va_end(ap);
558
    put_buffer(s, buf, strlen(buf));
559
    return ret;
560
}
561
#endif //CONFIG_ENCODERS
562

    
563
/* note: unlike fgets, the EOL character is not returned and a whole
564
   line is parsed. return NULL if first char read was EOF */
565
char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
566
{
567
    int c;
568
    char *q;
569

    
570
    c = url_fgetc(s);
571
    if (c == EOF)
572
        return NULL;
573
    q = buf;
574
    for(;;) {
575
        if (c == EOF || c == '\n')
576
            break;
577
        if ((q - buf) < buf_size - 1)
578
            *q++ = c;
579
        c = url_fgetc(s);
580
    }
581
    if (buf_size > 0)
582
        *q = '\0';
583
    return buf;
584
}
585

    
586
/* 
587
 * Return the maximum packet size associated to packetized buffered file
588
 * handle. If the file is not packetized (stream like http or file on
589
 * disk), then 0 is returned.
590
 * 
591
 * @param h buffered file handle
592
 * @return maximum packet size in bytes
593
 */
594
int url_fget_max_packet_size(ByteIOContext *s)
595
{
596
    return s->max_packet_size;
597
}
598

    
599
#ifdef CONFIG_ENCODERS
600
/* buffer handling */
601
int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags)
602
{
603
    return init_put_byte(s, buf, buf_size, 
604
                         (flags & URL_WRONLY || flags & URL_RDWR),
605
                         NULL, NULL, NULL, NULL);
606
}
607

    
608
/* return the written or read size */
609
int url_close_buf(ByteIOContext *s)
610
{
611
    put_flush_packet(s);
612
    return s->buf_ptr - s->buffer;
613
}
614

    
615
/* output in a dynamic buffer */
616

    
617
typedef struct DynBuffer {
618
    int pos, size, allocated_size;
619
    uint8_t *buffer;
620
    int io_buffer_size;
621
    uint8_t io_buffer[1];
622
} DynBuffer;
623

    
624
static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
625
{
626
    DynBuffer *d = opaque;
627
    int new_size, new_allocated_size;
628
    
629
    /* reallocate buffer if needed */
630
    new_size = d->pos + buf_size;
631
    new_allocated_size = d->allocated_size;
632
    while (new_size > new_allocated_size) {
633
        if (!new_allocated_size)
634
            new_allocated_size = new_size;
635
        else
636
            new_allocated_size = (new_allocated_size * 3) / 2 + 1;    
637
    }
638
    
639
    if (new_allocated_size > d->allocated_size) {
640
        d->buffer = av_realloc(d->buffer, new_allocated_size);
641
        if(d->buffer == NULL)
642
             return -1234;
643
        d->allocated_size = new_allocated_size;
644
    }
645
    memcpy(d->buffer + d->pos, buf, buf_size);
646
    d->pos = new_size;
647
    if (d->pos > d->size)
648
        d->size = d->pos;
649
    return buf_size;
650
}
651

    
652
static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
653
{
654
    unsigned char buf1[4];
655
    int ret;
656

    
657
    /* packetized write: output the header */
658
    buf1[0] = (buf_size >> 24);
659
    buf1[1] = (buf_size >> 16);
660
    buf1[2] = (buf_size >> 8);
661
    buf1[3] = (buf_size);
662
    ret= dyn_buf_write(opaque, buf1, 4);
663
    if(ret < 0)
664
        return ret;
665

    
666
    /* then the data */
667
    return dyn_buf_write(opaque, buf, buf_size);
668
}
669

    
670
static int dyn_buf_seek(void *opaque, offset_t offset, int whence)
671
{
672
    DynBuffer *d = opaque;
673

    
674
    if (whence == SEEK_CUR)
675
        offset += d->pos;
676
    else if (whence == SEEK_END)
677
        offset += d->size;
678
    if (offset < 0 || offset > 0x7fffffffLL)
679
        return -1;
680
    d->pos = offset;
681
    return 0;
682
}
683

    
684
static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
685
{
686
    DynBuffer *d;
687
    int io_buffer_size, ret;
688
    
689
    if (max_packet_size) 
690
        io_buffer_size = max_packet_size;
691
    else
692
        io_buffer_size = 1024;
693
        
694
    d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
695
    if (!d)
696
        return -1;
697
    d->io_buffer_size = io_buffer_size;
698
    d->buffer = NULL;
699
    d->pos = 0;
700
    d->size = 0;
701
    d->allocated_size = 0;
702
    ret = init_put_byte(s, d->io_buffer, io_buffer_size, 
703
                        1, d, NULL, 
704
                        max_packet_size ? dyn_packet_buf_write : dyn_buf_write, 
705
                        max_packet_size ? NULL : dyn_buf_seek);
706
    if (ret == 0) {
707
        s->max_packet_size = max_packet_size;
708
    }
709
    return ret;
710
}
711

    
712
/*
713
 * Open a write only memory stream.
714
 * 
715
 * @param s new IO context
716
 * @return zero if no error.
717
 */
718
int url_open_dyn_buf(ByteIOContext *s)
719
{
720
    return url_open_dyn_buf_internal(s, 0);
721
}
722

    
723
/*
724
 * Open a write only packetized memory stream with a maximum packet
725
 * size of 'max_packet_size'.  The stream is stored in a memory buffer
726
 * with a big endian 4 byte header giving the packet size in bytes.
727
 * 
728
 * @param s new IO context
729
 * @param max_packet_size maximum packet size (must be > 0) 
730
 * @return zero if no error.
731
 */
732
int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
733
{
734
    if (max_packet_size <= 0)
735
        return -1;
736
    return url_open_dyn_buf_internal(s, max_packet_size);
737
}
738

    
739
/* 
740
 * Return the written size and a pointer to the buffer. The buffer
741
 *  must be freed with av_free(). 
742
 * @param s IO context
743
 * @param pointer to a byte buffer
744
 * @return the length of the byte buffer
745
 */
746
int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
747
{
748
    DynBuffer *d = s->opaque;
749
    int size;
750

    
751
    put_flush_packet(s);
752

    
753
    *pbuffer = d->buffer;
754
    size = d->size;
755
    av_free(d);
756
    return size;
757
}
758
#endif //CONFIG_ENCODERS