Statistics
| Branch: | Revision:

ffmpeg / libavformat / aviobuf.c @ 90aa6ace

History | View | Annotate | Download (20.1 KB)

1
/*
2
 * Buffered I/O for ffmpeg system
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/intreadwrite.h"
24
#include "avformat.h"
25
#include "avio.h"
26
#include <stdarg.h>
27

    
28
#define IO_BUFFER_SIZE 32768
29

    
30
static void fill_buffer(ByteIOContext *s);
31

    
32
int init_put_byte(ByteIOContext *s,
33
                  unsigned char *buffer,
34
                  int buffer_size,
35
                  int write_flag,
36
                  void *opaque,
37
                  int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
38
                  int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
39
                  int64_t (*seek)(void *opaque, int64_t offset, int whence))
40
{
41
    s->buffer = buffer;
42
    s->buffer_size = buffer_size;
43
    s->buf_ptr = buffer;
44
    s->opaque = opaque;
45
    url_resetbuf(s, write_flag ? URL_WRONLY : URL_RDONLY);
46
    s->write_packet = write_packet;
47
    s->read_packet = read_packet;
48
    s->seek = seek;
49
    s->pos = 0;
50
    s->must_flush = 0;
51
    s->eof_reached = 0;
52
    s->error = 0;
53
    s->is_streamed = 0;
54
    s->max_packet_size = 0;
55
    s->update_checksum= NULL;
56
    if(!read_packet && !write_flag){
57
        s->pos = buffer_size;
58
        s->buf_end = s->buffer + buffer_size;
59
    }
60
    s->read_pause = NULL;
61
    s->read_seek  = NULL;
62
    return 0;
63
}
64

    
65
ByteIOContext *av_alloc_put_byte(
66
                  unsigned char *buffer,
67
                  int buffer_size,
68
                  int write_flag,
69
                  void *opaque,
70
                  int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
71
                  int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
72
                  int64_t (*seek)(void *opaque, int64_t offset, int whence))
73
{
74
    ByteIOContext *s = av_mallocz(sizeof(ByteIOContext));
75
    init_put_byte(s, buffer, buffer_size, write_flag, opaque,
76
                  read_packet, write_packet, seek);
77
    return s;
78
}
79

    
80
static void flush_buffer(ByteIOContext *s)
81
{
82
    if (s->buf_ptr > s->buffer) {
83
        if (s->write_packet && !s->error){
84
            int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
85
            if(ret < 0){
86
                s->error = ret;
87
            }
88
        }
89
        if(s->update_checksum){
90
            s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
91
            s->checksum_ptr= s->buffer;
92
        }
93
        s->pos += s->buf_ptr - s->buffer;
94
    }
95
    s->buf_ptr = s->buffer;
96
}
97

    
98
void put_byte(ByteIOContext *s, int b)
99
{
100
    *(s->buf_ptr)++ = b;
101
    if (s->buf_ptr >= s->buf_end)
102
        flush_buffer(s);
103
}
104

    
105
void put_buffer(ByteIOContext *s, const unsigned char *buf, int size)
106
{
107
    while (size > 0) {
108
        int len = FFMIN(s->buf_end - s->buf_ptr, size);
109
        memcpy(s->buf_ptr, buf, len);
110
        s->buf_ptr += len;
111

    
112
        if (s->buf_ptr >= s->buf_end)
113
            flush_buffer(s);
114

    
115
        buf += len;
116
        size -= len;
117
    }
118
}
119

    
120
void put_flush_packet(ByteIOContext *s)
121
{
122
    flush_buffer(s);
123
    s->must_flush = 0;
124
}
125

    
126
int64_t url_fseek(ByteIOContext *s, int64_t offset, int whence)
127
{
128
    int64_t offset1;
129
    int64_t pos;
130

    
131
    if(!s)
132
        return AVERROR(EINVAL);
133

    
134
    pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
135

    
136
    if (whence != SEEK_CUR && whence != SEEK_SET)
137
        return AVERROR(EINVAL);
138

    
139
    if (whence == SEEK_CUR) {
140
        offset1 = pos + (s->buf_ptr - s->buffer);
141
        if (offset == 0)
142
            return offset1;
143
        offset += offset1;
144
    }
145
    offset1 = offset - pos;
146
    if (!s->must_flush &&
147
        offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
148
        /* can do the seek inside the buffer */
149
        s->buf_ptr = s->buffer + offset1;
150
    } else if(s->is_streamed && !s->write_flag &&
151
              offset1 >= 0 && offset1 < (s->buf_end - s->buffer) + (1<<16)){
152
        while(s->pos < offset && !s->eof_reached)
153
            fill_buffer(s);
154
        if (s->eof_reached)
155
            return AVERROR(EPIPE);
156
        s->buf_ptr = s->buf_end + offset - s->pos;
157
    } else {
158
        int64_t res = AVERROR(EPIPE);
159

    
160
#if CONFIG_MUXERS || CONFIG_NETWORK
161
        if (s->write_flag) {
162
            flush_buffer(s);
163
            s->must_flush = 1;
164
        }
165
#endif /* CONFIG_MUXERS || CONFIG_NETWORK */
166
        if (!s->seek || (res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
167
            return res;
168
        if (!s->write_flag)
169
            s->buf_end = s->buffer;
170
        s->buf_ptr = s->buffer;
171
        s->pos = offset;
172
    }
173
    s->eof_reached = 0;
174
    return offset;
175
}
176

    
177
void url_fskip(ByteIOContext *s, int64_t offset)
178
{
179
    url_fseek(s, offset, SEEK_CUR);
180
}
181

    
182
int64_t url_ftell(ByteIOContext *s)
183
{
184
    return url_fseek(s, 0, SEEK_CUR);
185
}
186

    
187
int64_t url_fsize(ByteIOContext *s)
188
{
189
    int64_t size;
190

    
191
    if(!s)
192
        return AVERROR(EINVAL);
193

    
194
    if (!s->seek)
195
        return AVERROR(EPIPE);
196
    size = s->seek(s->opaque, 0, AVSEEK_SIZE);
197
    if(size<0){
198
        if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
199
            return size;
200
        size++;
201
        s->seek(s->opaque, s->pos, SEEK_SET);
202
    }
203
    return size;
204
}
205

    
206
int url_feof(ByteIOContext *s)
207
{
208
    if(!s)
209
        return 0;
210
    return s->eof_reached;
211
}
212

    
213
int url_ferror(ByteIOContext *s)
214
{
215
    if(!s)
216
        return 0;
217
    return s->error;
218
}
219

    
220
void put_le32(ByteIOContext *s, unsigned int val)
221
{
222
    put_byte(s, val);
223
    put_byte(s, val >> 8);
224
    put_byte(s, val >> 16);
225
    put_byte(s, val >> 24);
226
}
227

    
228
void put_be32(ByteIOContext *s, unsigned int val)
229
{
230
    put_byte(s, val >> 24);
231
    put_byte(s, val >> 16);
232
    put_byte(s, val >> 8);
233
    put_byte(s, val);
234
}
235

    
236
void put_strz(ByteIOContext *s, const char *str)
237
{
238
    if (str)
239
        put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
240
    else
241
        put_byte(s, 0);
242
}
243

    
244
void put_le64(ByteIOContext *s, uint64_t val)
245
{
246
    put_le32(s, (uint32_t)(val & 0xffffffff));
247
    put_le32(s, (uint32_t)(val >> 32));
248
}
249

    
250
void put_be64(ByteIOContext *s, uint64_t val)
251
{
252
    put_be32(s, (uint32_t)(val >> 32));
253
    put_be32(s, (uint32_t)(val & 0xffffffff));
254
}
255

    
256
void put_le16(ByteIOContext *s, unsigned int val)
257
{
258
    put_byte(s, val);
259
    put_byte(s, val >> 8);
260
}
261

    
262
void put_be16(ByteIOContext *s, unsigned int val)
263
{
264
    put_byte(s, val >> 8);
265
    put_byte(s, val);
266
}
267

    
268
void put_le24(ByteIOContext *s, unsigned int val)
269
{
270
    put_le16(s, val & 0xffff);
271
    put_byte(s, val >> 16);
272
}
273

    
274
void put_be24(ByteIOContext *s, unsigned int val)
275
{
276
    put_be16(s, val >> 8);
277
    put_byte(s, val);
278
}
279

    
280
void put_tag(ByteIOContext *s, const char *tag)
281
{
282
    while (*tag) {
283
        put_byte(s, *tag++);
284
    }
285
}
286

    
287
/* Input stream */
288

    
289
static void fill_buffer(ByteIOContext *s)
290
{
291
    uint8_t *dst= !s->max_packet_size && s->buf_end - s->buffer < s->buffer_size ? s->buf_ptr : s->buffer;
292
    int len= s->buffer_size - (dst - s->buffer);
293

    
294
    assert(s->buf_ptr == s->buf_end);
295

    
296
    /* no need to do anything if EOF already reached */
297
    if (s->eof_reached)
298
        return;
299

    
300
    if(s->update_checksum && dst == s->buffer){
301
        if(s->buf_end > s->checksum_ptr)
302
            s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
303
        s->checksum_ptr= s->buffer;
304
    }
305

    
306
    if(s->read_packet)
307
        len = s->read_packet(s->opaque, dst, len);
308
    else
309
        len = 0;
310
    if (len <= 0) {
311
        /* do not modify buffer if EOF reached so that a seek back can
312
           be done without rereading data */
313
        s->eof_reached = 1;
314
        if(len<0)
315
            s->error= len;
316
    } else {
317
        s->pos += len;
318
        s->buf_ptr = dst;
319
        s->buf_end = dst + len;
320
    }
321
}
322

    
323
unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
324
                                    unsigned int len)
325
{
326
    return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
327
}
328

    
329
unsigned long get_checksum(ByteIOContext *s)
330
{
331
    s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
332
    s->update_checksum= NULL;
333
    return s->checksum;
334
}
335

    
336
void init_checksum(ByteIOContext *s,
337
                   unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
338
                   unsigned long checksum)
339
{
340
    s->update_checksum= update_checksum;
341
    if(s->update_checksum){
342
        s->checksum= checksum;
343
        s->checksum_ptr= s->buf_ptr;
344
    }
345
}
346

    
347
/* XXX: put an inline version */
348
int get_byte(ByteIOContext *s)
349
{
350
    if (s->buf_ptr < s->buf_end) {
351
        return *s->buf_ptr++;
352
    } else {
353
        fill_buffer(s);
354
        if (s->buf_ptr < s->buf_end)
355
            return *s->buf_ptr++;
356
        else
357
            return 0;
358
    }
359
}
360

    
361
int url_fgetc(ByteIOContext *s)
362
{
363
    if (s->buf_ptr < s->buf_end) {
364
        return *s->buf_ptr++;
365
    } else {
366
        fill_buffer(s);
367
        if (s->buf_ptr < s->buf_end)
368
            return *s->buf_ptr++;
369
        else
370
            return URL_EOF;
371
    }
372
}
373

    
374
int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
375
{
376
    int len, size1;
377

    
378
    size1 = size;
379
    while (size > 0) {
380
        len = s->buf_end - s->buf_ptr;
381
        if (len > size)
382
            len = size;
383
        if (len == 0) {
384
            if(size > s->buffer_size && !s->update_checksum){
385
                if(s->read_packet)
386
                    len = s->read_packet(s->opaque, buf, size);
387
                if (len <= 0) {
388
                    /* do not modify buffer if EOF reached so that a seek back can
389
                    be done without rereading data */
390
                    s->eof_reached = 1;
391
                    if(len<0)
392
                        s->error= len;
393
                    break;
394
                } else {
395
                    s->pos += len;
396
                    size -= len;
397
                    buf += len;
398
                    s->buf_ptr = s->buffer;
399
                    s->buf_end = s->buffer/* + len*/;
400
                }
401
            }else{
402
                fill_buffer(s);
403
                len = s->buf_end - s->buf_ptr;
404
                if (len == 0)
405
                    break;
406
            }
407
        } else {
408
            memcpy(buf, s->buf_ptr, len);
409
            buf += len;
410
            s->buf_ptr += len;
411
            size -= len;
412
        }
413
    }
414
    if (size1 == size) {
415
        if (url_ferror(s)) return url_ferror(s);
416
        if (url_feof(s))   return AVERROR_EOF;
417
    }
418
    return size1 - size;
419
}
420

    
421
int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
422
{
423
    int len;
424

    
425
    if(size<0)
426
        return -1;
427

    
428
    len = s->buf_end - s->buf_ptr;
429
    if (len == 0) {
430
        fill_buffer(s);
431
        len = s->buf_end - s->buf_ptr;
432
    }
433
    if (len > size)
434
        len = size;
435
    memcpy(buf, s->buf_ptr, len);
436
    s->buf_ptr += len;
437
    if (!len) {
438
        if (url_ferror(s)) return url_ferror(s);
439
        if (url_feof(s))   return AVERROR_EOF;
440
    }
441
    return len;
442
}
443

    
444
unsigned int get_le16(ByteIOContext *s)
445
{
446
    unsigned int val;
447
    val = get_byte(s);
448
    val |= get_byte(s) << 8;
449
    return val;
450
}
451

    
452
unsigned int get_le24(ByteIOContext *s)
453
{
454
    unsigned int val;
455
    val = get_le16(s);
456
    val |= get_byte(s) << 16;
457
    return val;
458
}
459

    
460
unsigned int get_le32(ByteIOContext *s)
461
{
462
    unsigned int val;
463
    val = get_le16(s);
464
    val |= get_le16(s) << 16;
465
    return val;
466
}
467

    
468
uint64_t get_le64(ByteIOContext *s)
469
{
470
    uint64_t val;
471
    val = (uint64_t)get_le32(s);
472
    val |= (uint64_t)get_le32(s) << 32;
473
    return val;
474
}
475

    
476
unsigned int get_be16(ByteIOContext *s)
477
{
478
    unsigned int val;
479
    val = get_byte(s) << 8;
480
    val |= get_byte(s);
481
    return val;
482
}
483

    
484
unsigned int get_be24(ByteIOContext *s)
485
{
486
    unsigned int val;
487
    val = get_be16(s) << 8;
488
    val |= get_byte(s);
489
    return val;
490
}
491
unsigned int get_be32(ByteIOContext *s)
492
{
493
    unsigned int val;
494
    val = get_be16(s) << 16;
495
    val |= get_be16(s);
496
    return val;
497
}
498

    
499
char *get_strz(ByteIOContext *s, char *buf, int maxlen)
500
{
501
    int i = 0;
502
    char c;
503

    
504
    while ((c = get_byte(s))) {
505
        if (i < maxlen-1)
506
            buf[i++] = c;
507
    }
508

    
509
    buf[i] = 0; /* Ensure null terminated, but may be truncated */
510

    
511
    return buf;
512
}
513

    
514
uint64_t get_be64(ByteIOContext *s)
515
{
516
    uint64_t val;
517
    val = (uint64_t)get_be32(s) << 32;
518
    val |= (uint64_t)get_be32(s);
519
    return val;
520
}
521

    
522
uint64_t ff_get_v(ByteIOContext *bc){
523
    uint64_t val = 0;
524
    int tmp;
525

    
526
    do{
527
        tmp = get_byte(bc);
528
        val= (val<<7) + (tmp&127);
529
    }while(tmp&128);
530
    return val;
531
}
532

    
533
int url_fdopen(ByteIOContext **s, URLContext *h)
534
{
535
    uint8_t *buffer;
536
    int buffer_size, max_packet_size;
537

    
538

    
539
    max_packet_size = url_get_max_packet_size(h);
540
    if (max_packet_size) {
541
        buffer_size = max_packet_size; /* no need to bufferize more than one packet */
542
    } else {
543
        buffer_size = IO_BUFFER_SIZE;
544
    }
545
    buffer = av_malloc(buffer_size);
546
    if (!buffer)
547
        return AVERROR(ENOMEM);
548

    
549
    *s = av_mallocz(sizeof(ByteIOContext));
550
    if(!*s) {
551
        av_free(buffer);
552
        return AVERROR(ENOMEM);
553
    }
554

    
555
    if (init_put_byte(*s, buffer, buffer_size,
556
                      (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
557
                      url_read, url_write, url_seek) < 0) {
558
        av_free(buffer);
559
        av_freep(s);
560
        return AVERROR(EIO);
561
    }
562
    (*s)->is_streamed = h->is_streamed;
563
    (*s)->max_packet_size = max_packet_size;
564
    if(h->prot) {
565
        (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
566
        (*s)->read_seek  = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
567
    }
568
    return 0;
569
}
570

    
571
int url_setbufsize(ByteIOContext *s, int buf_size)
572
{
573
    uint8_t *buffer;
574
    buffer = av_malloc(buf_size);
575
    if (!buffer)
576
        return AVERROR(ENOMEM);
577

    
578
    av_free(s->buffer);
579
    s->buffer = buffer;
580
    s->buffer_size = buf_size;
581
    s->buf_ptr = buffer;
582
    url_resetbuf(s, s->write_flag ? URL_WRONLY : URL_RDONLY);
583
    return 0;
584
}
585

    
586
int url_resetbuf(ByteIOContext *s, int flags)
587
{
588
    URLContext *h = s->opaque;
589
    if ((flags & URL_RDWR) || (h && h->flags != flags && !h->flags & URL_RDWR))
590
        return AVERROR(EINVAL);
591

    
592
    if (flags & URL_WRONLY) {
593
        s->buf_end = s->buffer + s->buffer_size;
594
        s->write_flag = 1;
595
    } else {
596
        s->buf_end = s->buffer;
597
        s->write_flag = 0;
598
    }
599
    return 0;
600
}
601

    
602
int url_fopen(ByteIOContext **s, const char *filename, int flags)
603
{
604
    URLContext *h;
605
    int err;
606

    
607
    err = url_open(&h, filename, flags);
608
    if (err < 0)
609
        return err;
610
    err = url_fdopen(s, h);
611
    if (err < 0) {
612
        url_close(h);
613
        return err;
614
    }
615
    return 0;
616
}
617

    
618
int url_fclose(ByteIOContext *s)
619
{
620
    URLContext *h = s->opaque;
621

    
622
    av_free(s->buffer);
623
    av_free(s);
624
    return url_close(h);
625
}
626

    
627
URLContext *url_fileno(ByteIOContext *s)
628
{
629
    return s->opaque;
630
}
631

    
632
#if CONFIG_MUXERS
633
int url_fprintf(ByteIOContext *s, const char *fmt, ...)
634
{
635
    va_list ap;
636
    char buf[4096];
637
    int ret;
638

    
639
    va_start(ap, fmt);
640
    ret = vsnprintf(buf, sizeof(buf), fmt, ap);
641
    va_end(ap);
642
    put_buffer(s, buf, strlen(buf));
643
    return ret;
644
}
645
#endif //CONFIG_MUXERS
646

    
647
char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
648
{
649
    int c;
650
    char *q;
651

    
652
    c = url_fgetc(s);
653
    if (c == EOF)
654
        return NULL;
655
    q = buf;
656
    for(;;) {
657
        if (c == EOF || c == '\n')
658
            break;
659
        if ((q - buf) < buf_size - 1)
660
            *q++ = c;
661
        c = url_fgetc(s);
662
    }
663
    if (buf_size > 0)
664
        *q = '\0';
665
    return buf;
666
}
667

    
668
int url_fget_max_packet_size(ByteIOContext *s)
669
{
670
    return s->max_packet_size;
671
}
672

    
673
int av_url_read_fpause(ByteIOContext *s, int pause)
674
{
675
    if (!s->read_pause)
676
        return AVERROR(ENOSYS);
677
    return s->read_pause(s->opaque, pause);
678
}
679

    
680
int64_t av_url_read_fseek(ByteIOContext *s, int stream_index,
681
                          int64_t timestamp, int flags)
682
{
683
    URLContext *h = s->opaque;
684
    int64_t ret;
685
    if (!s->read_seek)
686
        return AVERROR(ENOSYS);
687
    ret = s->read_seek(h, stream_index, timestamp, flags);
688
    if(ret >= 0) {
689
        s->buf_ptr = s->buf_end; // Flush buffer
690
        s->pos = s->seek(h, 0, SEEK_CUR);
691
    }
692
    return ret;
693
}
694

    
695
/* url_open_dyn_buf and url_close_dyn_buf are used in rtp.c to send a response
696
 * back to the server even if CONFIG_MUXERS is false. */
697
#if CONFIG_MUXERS || CONFIG_NETWORK
698
/* buffer handling */
699
int url_open_buf(ByteIOContext **s, uint8_t *buf, int buf_size, int flags)
700
{
701
    int ret;
702
    *s = av_mallocz(sizeof(ByteIOContext));
703
    if(!*s)
704
        return AVERROR(ENOMEM);
705
    ret = init_put_byte(*s, buf, buf_size,
706
                        (flags & URL_WRONLY || flags & URL_RDWR),
707
                        NULL, NULL, NULL, NULL);
708
    if(ret != 0)
709
        av_freep(s);
710
    return ret;
711
}
712

    
713
int url_close_buf(ByteIOContext *s)
714
{
715
    put_flush_packet(s);
716
    return s->buf_ptr - s->buffer;
717
}
718

    
719
/* output in a dynamic buffer */
720

    
721
typedef struct DynBuffer {
722
    int pos, size, allocated_size;
723
    uint8_t *buffer;
724
    int io_buffer_size;
725
    uint8_t io_buffer[1];
726
} DynBuffer;
727

    
728
static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
729
{
730
    DynBuffer *d = opaque;
731
    unsigned new_size, new_allocated_size;
732

    
733
    /* reallocate buffer if needed */
734
    new_size = d->pos + buf_size;
735
    new_allocated_size = d->allocated_size;
736
    if(new_size < d->pos || new_size > INT_MAX/2)
737
        return -1;
738
    while (new_size > new_allocated_size) {
739
        if (!new_allocated_size)
740
            new_allocated_size = new_size;
741
        else
742
            new_allocated_size += new_allocated_size / 2 + 1;
743
    }
744

    
745
    if (new_allocated_size > d->allocated_size) {
746
        d->buffer = av_realloc(d->buffer, new_allocated_size);
747
        if(d->buffer == NULL)
748
             return AVERROR(ENOMEM);
749
        d->allocated_size = new_allocated_size;
750
    }
751
    memcpy(d->buffer + d->pos, buf, buf_size);
752
    d->pos = new_size;
753
    if (d->pos > d->size)
754
        d->size = d->pos;
755
    return buf_size;
756
}
757

    
758
static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
759
{
760
    unsigned char buf1[4];
761
    int ret;
762

    
763
    /* packetized write: output the header */
764
    AV_WB32(buf1, buf_size);
765
    ret= dyn_buf_write(opaque, buf1, 4);
766
    if(ret < 0)
767
        return ret;
768

    
769
    /* then the data */
770
    return dyn_buf_write(opaque, buf, buf_size);
771
}
772

    
773
static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
774
{
775
    DynBuffer *d = opaque;
776

    
777
    if (whence == SEEK_CUR)
778
        offset += d->pos;
779
    else if (whence == SEEK_END)
780
        offset += d->size;
781
    if (offset < 0 || offset > 0x7fffffffLL)
782
        return -1;
783
    d->pos = offset;
784
    return 0;
785
}
786

    
787
static int url_open_dyn_buf_internal(ByteIOContext **s, int max_packet_size)
788
{
789
    DynBuffer *d;
790
    int ret;
791
    unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
792

    
793
    if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
794
        return -1;
795
    d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
796
    if (!d)
797
        return AVERROR(ENOMEM);
798
    *s = av_mallocz(sizeof(ByteIOContext));
799
    if(!*s) {
800
        av_free(d);
801
        return AVERROR(ENOMEM);
802
    }
803
    d->io_buffer_size = io_buffer_size;
804
    ret = init_put_byte(*s, d->io_buffer, io_buffer_size,
805
                        1, d, NULL,
806
                        max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
807
                        max_packet_size ? NULL : dyn_buf_seek);
808
    if (ret == 0) {
809
        (*s)->max_packet_size = max_packet_size;
810
    } else {
811
        av_free(d);
812
        av_freep(s);
813
    }
814
    return ret;
815
}
816

    
817
int url_open_dyn_buf(ByteIOContext **s)
818
{
819
    return url_open_dyn_buf_internal(s, 0);
820
}
821

    
822
int url_open_dyn_packet_buf(ByteIOContext **s, int max_packet_size)
823
{
824
    if (max_packet_size <= 0)
825
        return -1;
826
    return url_open_dyn_buf_internal(s, max_packet_size);
827
}
828

    
829
int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
830
{
831
    DynBuffer *d = s->opaque;
832
    int size;
833

    
834
    put_flush_packet(s);
835

    
836
    *pbuffer = d->buffer;
837
    size = d->size;
838
    av_free(d);
839
    av_free(s);
840
    return size;
841
}
842
#endif /* CONFIG_MUXERS || CONFIG_NETWORK */