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ffmpeg / libavformat / aviobuf.c @ ccb15994

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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
 *
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 * 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
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 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 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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                  offset_t (*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;
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    s->opaque = opaque;
43
    s->write_packet = write_packet;
44
    s->read_packet = read_packet;
45
    s->seek = seek;
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    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
static void flush_buffer(ByteIOContext *s)
57
{
58
    if (s->buf_ptr > s->buffer) {
59
        if (s->write_packet && !s->error){
60
            int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
61
            if(ret < 0){
62
                s->error = ret;
63
            }
64
        }
65
        if(s->update_checksum){
66
            s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
67
            s->checksum_ptr= s->buffer;
68
        }
69
        s->pos += s->buf_ptr - s->buffer;
70
    }
71
    s->buf_ptr = s->buffer;
72
}
73

    
74
void put_byte(ByteIOContext *s, int b)
75
{
76
    *(s->buf_ptr)++ = b;
77
    if (s->buf_ptr >= s->buf_end)
78
        flush_buffer(s);
79
}
80

    
81
void put_buffer(ByteIOContext *s, const unsigned char *buf, int size)
82
{
83
    int len;
84

    
85
    while (size > 0) {
86
        len = (s->buf_end - s->buf_ptr);
87
        if (len > size)
88
            len = size;
89
        memcpy(s->buf_ptr, buf, len);
90
        s->buf_ptr += len;
91

    
92
        if (s->buf_ptr >= s->buf_end)
93
            flush_buffer(s);
94

    
95
        buf += len;
96
        size -= len;
97
    }
98
}
99

    
100
void put_flush_packet(ByteIOContext *s)
101
{
102
    flush_buffer(s);
103
    s->must_flush = 0;
104
}
105

    
106
offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence)
107
{
108
    offset_t offset1;
109

    
110
    if (whence != SEEK_CUR && whence != SEEK_SET)
111
        return -EINVAL;
112

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

    
162
void url_fskip(ByteIOContext *s, offset_t offset)
163
{
164
    url_fseek(s, offset, SEEK_CUR);
165
}
166

    
167
offset_t url_ftell(ByteIOContext *s)
168
{
169
    return url_fseek(s, 0, SEEK_CUR);
170
}
171

    
172
offset_t url_fsize(ByteIOContext *s)
173
{
174
    offset_t size;
175

    
176
    if (!s->seek)
177
        return -EPIPE;
178
    size = s->seek(s->opaque, -1, SEEK_END) + 1;
179
    s->seek(s->opaque, s->pos, SEEK_SET);
180
    return size;
181
}
182

    
183
int url_feof(ByteIOContext *s)
184
{
185
    return s->eof_reached;
186
}
187

    
188
int url_ferror(ByteIOContext *s)
189
{
190
    return s->error;
191
}
192

    
193
#if defined(CONFIG_MUXERS) || defined(CONFIG_PROTOCOLS)
194
void put_le32(ByteIOContext *s, unsigned int val)
195
{
196
    put_byte(s, val);
197
    put_byte(s, val >> 8);
198
    put_byte(s, val >> 16);
199
    put_byte(s, val >> 24);
200
}
201

    
202
void put_be32(ByteIOContext *s, unsigned int val)
203
{
204
    put_byte(s, val >> 24);
205
    put_byte(s, val >> 16);
206
    put_byte(s, val >> 8);
207
    put_byte(s, val);
208
}
209

    
210
void put_strz(ByteIOContext *s, const char *str)
211
{
212
    if (str)
213
        put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
214
    else
215
        put_byte(s, 0);
216
}
217

    
218
void put_le64(ByteIOContext *s, uint64_t val)
219
{
220
    put_le32(s, (uint32_t)(val & 0xffffffff));
221
    put_le32(s, (uint32_t)(val >> 32));
222
}
223

    
224
void put_be64(ByteIOContext *s, uint64_t val)
225
{
226
    put_be32(s, (uint32_t)(val >> 32));
227
    put_be32(s, (uint32_t)(val & 0xffffffff));
228
}
229

    
230
void put_le16(ByteIOContext *s, unsigned int val)
231
{
232
    put_byte(s, val);
233
    put_byte(s, val >> 8);
234
}
235

    
236
void put_be16(ByteIOContext *s, unsigned int val)
237
{
238
    put_byte(s, val >> 8);
239
    put_byte(s, val);
240
}
241

    
242
void put_le24(ByteIOContext *s, unsigned int val)
243
{
244
    put_le16(s, val & 0xffff);
245
    put_byte(s, val >> 16);
246
}
247

    
248
void put_be24(ByteIOContext *s, unsigned int val)
249
{
250
    put_be16(s, val >> 8);
251
    put_byte(s, val);
252
}
253

    
254
void put_tag(ByteIOContext *s, const char *tag)
255
{
256
    while (*tag) {
257
        put_byte(s, *tag++);
258
    }
259
}
260
#endif //CONFIG_MUXERS || CONFIG_PROTOCOLS
261

    
262
/* Input stream */
263

    
264
static void fill_buffer(ByteIOContext *s)
265
{
266
    int len;
267

    
268
    /* no need to do anything if EOF already reached */
269
    if (s->eof_reached)
270
        return;
271

    
272
    if(s->update_checksum){
273
        if(s->buf_end > s->checksum_ptr)
274
            s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
275
        s->checksum_ptr= s->buffer;
276
    }
277

    
278
    len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
279
    if (len <= 0) {
280
        /* do not modify buffer if EOF reached so that a seek back can
281
           be done without rereading data */
282
        s->eof_reached = 1;
283
    if(len<0)
284
        s->error= len;
285
    } else {
286
        s->pos += len;
287
        s->buf_ptr = s->buffer;
288
        s->buf_end = s->buffer + len;
289
    }
290
}
291

    
292
unsigned long get_checksum(ByteIOContext *s){
293
    s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
294
    s->update_checksum= NULL;
295
    return s->checksum;
296
}
297

    
298
void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){
299
    s->update_checksum= update_checksum;
300
    if(s->update_checksum){
301
        s->checksum= checksum;
302
        s->checksum_ptr= s->buf_ptr;
303
    }
304
}
305

    
306
/* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
307
   necessary */
308
/* XXX: put an inline version */
309
int get_byte(ByteIOContext *s)
310
{
311
    if (s->buf_ptr < s->buf_end) {
312
        return *s->buf_ptr++;
313
    } else {
314
        fill_buffer(s);
315
        if (s->buf_ptr < s->buf_end)
316
            return *s->buf_ptr++;
317
        else
318
            return 0;
319
    }
320
}
321

    
322
/* NOTE: return URL_EOF (-1) if EOF */
323
int url_fgetc(ByteIOContext *s)
324
{
325
    if (s->buf_ptr < s->buf_end) {
326
        return *s->buf_ptr++;
327
    } else {
328
        fill_buffer(s);
329
        if (s->buf_ptr < s->buf_end)
330
            return *s->buf_ptr++;
331
        else
332
            return URL_EOF;
333
    }
334
}
335

    
336
int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
337
{
338
    int len, size1;
339

    
340
    size1 = size;
341
    while (size > 0) {
342
        len = s->buf_end - s->buf_ptr;
343
        if (len > size)
344
            len = size;
345
        if (len == 0) {
346
            if(size > s->buffer_size && !s->update_checksum){
347
                len = s->read_packet(s->opaque, buf, size);
348
                if (len <= 0) {
349
                    /* do not modify buffer if EOF reached so that a seek back can
350
                    be done without rereading data */
351
                    s->eof_reached = 1;
352
                    if(len<0)
353
                        s->error= len;
354
                    break;
355
                } else {
356
                    s->pos += len;
357
                    size -= len;
358
                    buf += len;
359
                    s->buf_ptr = s->buffer;
360
                    s->buf_end = s->buffer/* + len*/;
361
                }
362
            }else{
363
                fill_buffer(s);
364
                len = s->buf_end - s->buf_ptr;
365
                if (len == 0)
366
                    break;
367
            }
368
        } else {
369
            memcpy(buf, s->buf_ptr, len);
370
            buf += len;
371
            s->buf_ptr += len;
372
            size -= len;
373
        }
374
    }
375
    return size1 - size;
376
}
377

    
378
int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
379
{
380
    int len;
381

    
382
    if(size<0)
383
        return -1;
384

    
385
    len = s->buf_end - s->buf_ptr;
386
    if (len == 0) {
387
        fill_buffer(s);
388
        len = s->buf_end - s->buf_ptr;
389
    }
390
    if (len > size)
391
        len = size;
392
    memcpy(buf, s->buf_ptr, len);
393
    s->buf_ptr += len;
394
    return len;
395
}
396

    
397
unsigned int get_le16(ByteIOContext *s)
398
{
399
    unsigned int val;
400
    val = get_byte(s);
401
    val |= get_byte(s) << 8;
402
    return val;
403
}
404

    
405
unsigned int get_le24(ByteIOContext *s)
406
{
407
    unsigned int val;
408
    val = get_le16(s);
409
    val |= get_byte(s) << 16;
410
    return val;
411
}
412

    
413
unsigned int get_le32(ByteIOContext *s)
414
{
415
    unsigned int val;
416
    val = get_le16(s);
417
    val |= get_le16(s) << 16;
418
    return val;
419
}
420

    
421
uint64_t get_le64(ByteIOContext *s)
422
{
423
    uint64_t val;
424
    val = (uint64_t)get_le32(s);
425
    val |= (uint64_t)get_le32(s) << 32;
426
    return val;
427
}
428

    
429
unsigned int get_be16(ByteIOContext *s)
430
{
431
    unsigned int val;
432
    val = get_byte(s) << 8;
433
    val |= get_byte(s);
434
    return val;
435
}
436

    
437
unsigned int get_be24(ByteIOContext *s)
438
{
439
    unsigned int val;
440
    val = get_be16(s) << 8;
441
    val |= get_byte(s);
442
    return val;
443
}
444
unsigned int get_be32(ByteIOContext *s)
445
{
446
    unsigned int val;
447
    val = get_be16(s) << 16;
448
    val |= get_be16(s);
449
    return val;
450
}
451

    
452
char *get_strz(ByteIOContext *s, char *buf, int maxlen)
453
{
454
    int i = 0;
455
    char c;
456

    
457
    while ((c = get_byte(s))) {
458
        if (i < maxlen-1)
459
            buf[i++] = c;
460
    }
461

    
462
    buf[i] = 0; /* Ensure null terminated, but may be truncated */
463

    
464
    return buf;
465
}
466

    
467
uint64_t get_be64(ByteIOContext *s)
468
{
469
    uint64_t val;
470
    val = (uint64_t)get_be32(s) << 32;
471
    val |= (uint64_t)get_be32(s);
472
    return val;
473
}
474

    
475
/* link with avio functions */
476

    
477
#ifdef CONFIG_MUXERS
478
static int url_write_packet(void *opaque, uint8_t *buf, int buf_size)
479
{
480
    URLContext *h = opaque;
481
    return url_write(h, buf, buf_size);
482
}
483
#else
484
#define         url_write_packet NULL
485
#endif //CONFIG_MUXERS
486

    
487
static int url_read_packet(void *opaque, uint8_t *buf, int buf_size)
488
{
489
    URLContext *h = opaque;
490
    return url_read(h, buf, buf_size);
491
}
492

    
493
static offset_t url_seek_packet(void *opaque, offset_t offset, int whence)
494
{
495
    URLContext *h = opaque;
496
    return url_seek(h, offset, whence);
497
    //return 0;
498
}
499

    
500
int url_fdopen(ByteIOContext *s, URLContext *h)
501
{
502
    uint8_t *buffer;
503
    int buffer_size, max_packet_size;
504

    
505

    
506
    max_packet_size = url_get_max_packet_size(h);
507
    if (max_packet_size) {
508
        buffer_size = max_packet_size; /* no need to bufferize more than one packet */
509
    } else {
510
        buffer_size = IO_BUFFER_SIZE;
511
    }
512
    buffer = av_malloc(buffer_size);
513
    if (!buffer)
514
        return -ENOMEM;
515

    
516
    if (init_put_byte(s, buffer, buffer_size,
517
                      (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
518
                      url_read_packet, url_write_packet, url_seek_packet) < 0) {
519
        av_free(buffer);
520
        return AVERROR_IO;
521
    }
522
    s->is_streamed = h->is_streamed;
523
    s->max_packet_size = max_packet_size;
524
    return 0;
525
}
526

    
527
/* XXX: must be called before any I/O */
528
int url_setbufsize(ByteIOContext *s, int buf_size)
529
{
530
    uint8_t *buffer;
531
    buffer = av_malloc(buf_size);
532
    if (!buffer)
533
        return -ENOMEM;
534

    
535
    av_free(s->buffer);
536
    s->buffer = buffer;
537
    s->buffer_size = buf_size;
538
    s->buf_ptr = buffer;
539
    if (!s->write_flag)
540
        s->buf_end = buffer;
541
    else
542
        s->buf_end = buffer + buf_size;
543
    return 0;
544
}
545

    
546
/* NOTE: when opened as read/write, the buffers are only used for
547
   reading */
548
int url_fopen(ByteIOContext *s, const char *filename, int flags)
549
{
550
    URLContext *h;
551
    int err;
552

    
553
    err = url_open(&h, filename, flags);
554
    if (err < 0)
555
        return err;
556
    err = url_fdopen(s, h);
557
    if (err < 0) {
558
        url_close(h);
559
        return err;
560
    }
561
    return 0;
562
}
563

    
564
int url_fclose(ByteIOContext *s)
565
{
566
    URLContext *h = s->opaque;
567

    
568
    av_free(s->buffer);
569
    memset(s, 0, sizeof(ByteIOContext));
570
    return url_close(h);
571
}
572

    
573
URLContext *url_fileno(ByteIOContext *s)
574
{
575
    return s->opaque;
576
}
577

    
578
#ifdef CONFIG_MUXERS
579
/* XXX: currently size is limited */
580
int url_fprintf(ByteIOContext *s, const char *fmt, ...)
581
{
582
    va_list ap;
583
    char buf[4096];
584
    int ret;
585

    
586
    va_start(ap, fmt);
587
    ret = vsnprintf(buf, sizeof(buf), fmt, ap);
588
    va_end(ap);
589
    put_buffer(s, buf, strlen(buf));
590
    return ret;
591
}
592
#endif //CONFIG_MUXERS
593

    
594
/* note: unlike fgets, the EOL character is not returned and a whole
595
   line is parsed. return NULL if first char read was EOF */
596
char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
597
{
598
    int c;
599
    char *q;
600

    
601
    c = url_fgetc(s);
602
    if (c == EOF)
603
        return NULL;
604
    q = buf;
605
    for(;;) {
606
        if (c == EOF || c == '\n')
607
            break;
608
        if ((q - buf) < buf_size - 1)
609
            *q++ = c;
610
        c = url_fgetc(s);
611
    }
612
    if (buf_size > 0)
613
        *q = '\0';
614
    return buf;
615
}
616

    
617
/*
618
 * Return the maximum packet size associated to packetized buffered file
619
 * handle. If the file is not packetized (stream like http or file on
620
 * disk), then 0 is returned.
621
 *
622
 * @param h buffered file handle
623
 * @return maximum packet size in bytes
624
 */
625
int url_fget_max_packet_size(ByteIOContext *s)
626
{
627
    return s->max_packet_size;
628
}
629

    
630
#ifdef CONFIG_MUXERS
631
/* buffer handling */
632
int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags)
633
{
634
    return init_put_byte(s, buf, buf_size,
635
                         (flags & URL_WRONLY || flags & URL_RDWR),
636
                         NULL, NULL, NULL, NULL);
637
}
638

    
639
/* return the written or read size */
640
int url_close_buf(ByteIOContext *s)
641
{
642
    put_flush_packet(s);
643
    return s->buf_ptr - s->buffer;
644
}
645

    
646
/* output in a dynamic buffer */
647

    
648
typedef struct DynBuffer {
649
    int pos, size, allocated_size;
650
    uint8_t *buffer;
651
    int io_buffer_size;
652
    uint8_t io_buffer[1];
653
} DynBuffer;
654

    
655
static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
656
{
657
    DynBuffer *d = opaque;
658
    int new_size, new_allocated_size;
659

    
660
    /* reallocate buffer if needed */
661
    new_size = d->pos + buf_size;
662
    new_allocated_size = d->allocated_size;
663
    if(new_size < d->pos || new_size > INT_MAX/2)
664
        return -1;
665
    while (new_size > new_allocated_size) {
666
        if (!new_allocated_size)
667
            new_allocated_size = new_size;
668
        else
669
            new_allocated_size += new_allocated_size / 2 + 1;
670
    }
671

    
672
    if (new_allocated_size > d->allocated_size) {
673
        d->buffer = av_realloc(d->buffer, new_allocated_size);
674
        if(d->buffer == NULL)
675
             return -1234;
676
        d->allocated_size = new_allocated_size;
677
    }
678
    memcpy(d->buffer + d->pos, buf, buf_size);
679
    d->pos = new_size;
680
    if (d->pos > d->size)
681
        d->size = d->pos;
682
    return buf_size;
683
}
684

    
685
static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
686
{
687
    unsigned char buf1[4];
688
    int ret;
689

    
690
    /* packetized write: output the header */
691
    buf1[0] = (buf_size >> 24);
692
    buf1[1] = (buf_size >> 16);
693
    buf1[2] = (buf_size >> 8);
694
    buf1[3] = (buf_size);
695
    ret= dyn_buf_write(opaque, buf1, 4);
696
    if(ret < 0)
697
        return ret;
698

    
699
    /* then the data */
700
    return dyn_buf_write(opaque, buf, buf_size);
701
}
702

    
703
static offset_t dyn_buf_seek(void *opaque, offset_t offset, int whence)
704
{
705
    DynBuffer *d = opaque;
706

    
707
    if (whence == SEEK_CUR)
708
        offset += d->pos;
709
    else if (whence == SEEK_END)
710
        offset += d->size;
711
    if (offset < 0 || offset > 0x7fffffffLL)
712
        return -1;
713
    d->pos = offset;
714
    return 0;
715
}
716

    
717
static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
718
{
719
    DynBuffer *d;
720
    int io_buffer_size, ret;
721

    
722
    if (max_packet_size)
723
        io_buffer_size = max_packet_size;
724
    else
725
        io_buffer_size = 1024;
726

    
727
    if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
728
        return -1;
729
    d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
730
    if (!d)
731
        return -1;
732
    d->io_buffer_size = io_buffer_size;
733
    d->buffer = NULL;
734
    d->pos = 0;
735
    d->size = 0;
736
    d->allocated_size = 0;
737
    ret = init_put_byte(s, d->io_buffer, io_buffer_size,
738
                        1, d, NULL,
739
                        max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
740
                        max_packet_size ? NULL : dyn_buf_seek);
741
    if (ret == 0) {
742
        s->max_packet_size = max_packet_size;
743
    }
744
    return ret;
745
}
746

    
747
/*
748
 * Open a write only memory stream.
749
 *
750
 * @param s new IO context
751
 * @return zero if no error.
752
 */
753
int url_open_dyn_buf(ByteIOContext *s)
754
{
755
    return url_open_dyn_buf_internal(s, 0);
756
}
757

    
758
/*
759
 * Open a write only packetized memory stream with a maximum packet
760
 * size of 'max_packet_size'.  The stream is stored in a memory buffer
761
 * with a big endian 4 byte header giving the packet size in bytes.
762
 *
763
 * @param s new IO context
764
 * @param max_packet_size maximum packet size (must be > 0)
765
 * @return zero if no error.
766
 */
767
int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
768
{
769
    if (max_packet_size <= 0)
770
        return -1;
771
    return url_open_dyn_buf_internal(s, max_packet_size);
772
}
773

    
774
/*
775
 * Return the written size and a pointer to the buffer. The buffer
776
 *  must be freed with av_free().
777
 * @param s IO context
778
 * @param pointer to a byte buffer
779
 * @return the length of the byte buffer
780
 */
781
int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
782
{
783
    DynBuffer *d = s->opaque;
784
    int size;
785

    
786
    put_flush_packet(s);
787

    
788
    *pbuffer = d->buffer;
789
    size = d->size;
790
    av_free(d);
791
    return size;
792
}
793
#endif //CONFIG_MUXERS