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ffmpeg / libavformat / aviobuf.c @ 3abe5fbd

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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
 *
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 * 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
#include "avformat.h"
22
#include "avio.h"
23
#include "crc.h"
24
#include <stdarg.h>
25

    
26
#define IO_BUFFER_SIZE 32768
27

    
28
static void fill_buffer(ByteIOContext *s);
29

    
30
int init_put_byte(ByteIOContext *s,
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                  unsigned char *buffer,
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                  int buffer_size,
33
                  int write_flag,
34
                  void *opaque,
35
                  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))
38
{
39
    s->buffer = buffer;
40
    s->buffer_size = buffer_size;
41
    s->buf_ptr = buffer;
42
    url_resetbuf(s, write_flag ? URL_WRONLY : URL_RDONLY);
43
    s->opaque = opaque;
44
    s->write_packet = write_packet;
45
    s->read_packet = read_packet;
46
    s->seek = seek;
47
    s->pos = 0;
48
    s->must_flush = 0;
49
    s->eof_reached = 0;
50
    s->error = 0;
51
    s->is_streamed = 0;
52
    s->max_packet_size = 0;
53
    s->update_checksum= NULL;
54
    if(!read_packet && !write_flag){
55
        s->pos = buffer_size;
56
        s->buf_end = s->buffer + buffer_size;
57
    }
58
    s->read_pause = NULL;
59
    s->read_seek  = NULL;
60
    return 0;
61
}
62

    
63
ByteIOContext *av_alloc_put_byte(
64
                  unsigned char *buffer,
65
                  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)) {
71
    ByteIOContext *s = av_mallocz(sizeof(ByteIOContext));
72
    init_put_byte(s, buffer, buffer_size, write_flag, opaque,
73
                  read_packet, write_packet, seek);
74
    return s;
75
}
76

    
77
static void flush_buffer(ByteIOContext *s)
78
{
79
    if (s->buf_ptr > s->buffer) {
80
        if (s->write_packet && !s->error){
81
            int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
82
            if(ret < 0){
83
                s->error = ret;
84
            }
85
        }
86
        if(s->update_checksum){
87
            s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
88
            s->checksum_ptr= s->buffer;
89
        }
90
        s->pos += s->buf_ptr - s->buffer;
91
    }
92
    s->buf_ptr = s->buffer;
93
}
94

    
95
void put_byte(ByteIOContext *s, int b)
96
{
97
    *(s->buf_ptr)++ = b;
98
    if (s->buf_ptr >= s->buf_end)
99
        flush_buffer(s);
100
}
101

    
102
void put_buffer(ByteIOContext *s, const unsigned char *buf, int size)
103
{
104
    int len;
105

    
106
    while (size > 0) {
107
        len = (s->buf_end - s->buf_ptr);
108
        if (len > size)
109
            len = size;
110
        memcpy(s->buf_ptr, buf, len);
111
        s->buf_ptr += len;
112

    
113
        if (s->buf_ptr >= s->buf_end)
114
            flush_buffer(s);
115

    
116
        buf += len;
117
        size -= len;
118
    }
119
}
120

    
121
void put_flush_packet(ByteIOContext *s)
122
{
123
    flush_buffer(s);
124
    s->must_flush = 0;
125
}
126

    
127
offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence)
128
{
129
    offset_t offset1;
130
    offset_t pos;
131

    
132
    if(!s)
133
        return AVERROR(EINVAL);
134

    
135
    pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
136

    
137
    if (whence != SEEK_CUR && whence != SEEK_SET)
138
        return AVERROR(EINVAL);
139

    
140
    if (whence == SEEK_CUR) {
141
        offset1 = pos + (s->buf_ptr - s->buffer);
142
        if (offset == 0)
143
            return offset1;
144
        offset += offset1;
145
    }
146
    offset1 = offset - pos;
147
    if (!s->must_flush &&
148
        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 if(s->is_streamed && !s->write_flag &&
152
              offset1 >= 0 && offset1 < (s->buf_end - s->buffer) + (1<<16)){
153
        while(s->pos < offset && !s->eof_reached)
154
            fill_buffer(s);
155
        if (s->eof_reached)
156
            return AVERROR(EPIPE);
157
        s->buf_ptr = s->buf_end + offset - s->pos;
158
    } else {
159
        offset_t res = AVERROR(EPIPE);
160

    
161
#if defined(CONFIG_MUXERS) || defined(CONFIG_NETWORK)
162
        if (s->write_flag) {
163
            flush_buffer(s);
164
            s->must_flush = 1;
165
        } else
166
#endif /* defined(CONFIG_MUXERS) || defined(CONFIG_NETWORK) */
167
        {
168
            s->buf_end = s->buffer;
169
        }
170
        s->buf_ptr = s->buffer;
171
        if (!s->seek || (res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
172
            return res;
173
        s->pos = offset;
174
    }
175
    s->eof_reached = 0;
176
    return offset;
177
}
178

    
179
void url_fskip(ByteIOContext *s, offset_t offset)
180
{
181
    url_fseek(s, offset, SEEK_CUR);
182
}
183

    
184
offset_t url_ftell(ByteIOContext *s)
185
{
186
    return url_fseek(s, 0, SEEK_CUR);
187
}
188

    
189
offset_t url_fsize(ByteIOContext *s)
190
{
191
    offset_t size;
192

    
193
    if(!s)
194
        return AVERROR(EINVAL);
195

    
196
    if (!s->seek)
197
        return AVERROR(EPIPE);
198
    size = s->seek(s->opaque, 0, AVSEEK_SIZE);
199
    if(size<0){
200
        if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
201
            return size;
202
        size++;
203
        s->seek(s->opaque, s->pos, SEEK_SET);
204
    }
205
    return size;
206
}
207

    
208
int url_feof(ByteIOContext *s)
209
{
210
    if(!s)
211
        return 0;
212
    return s->eof_reached;
213
}
214

    
215
int url_ferror(ByteIOContext *s)
216
{
217
    if(!s)
218
        return 0;
219
    return s->error;
220
}
221

    
222
void put_le32(ByteIOContext *s, unsigned int val)
223
{
224
    put_byte(s, val);
225
    put_byte(s, val >> 8);
226
    put_byte(s, val >> 16);
227
    put_byte(s, val >> 24);
228
}
229

    
230
void put_be32(ByteIOContext *s, unsigned int val)
231
{
232
    put_byte(s, val >> 24);
233
    put_byte(s, val >> 16);
234
    put_byte(s, val >> 8);
235
    put_byte(s, val);
236
}
237

    
238
void put_strz(ByteIOContext *s, const char *str)
239
{
240
    if (str)
241
        put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
242
    else
243
        put_byte(s, 0);
244
}
245

    
246
void put_le64(ByteIOContext *s, uint64_t val)
247
{
248
    put_le32(s, (uint32_t)(val & 0xffffffff));
249
    put_le32(s, (uint32_t)(val >> 32));
250
}
251

    
252
void put_be64(ByteIOContext *s, uint64_t val)
253
{
254
    put_be32(s, (uint32_t)(val >> 32));
255
    put_be32(s, (uint32_t)(val & 0xffffffff));
256
}
257

    
258
void put_le16(ByteIOContext *s, unsigned int val)
259
{
260
    put_byte(s, val);
261
    put_byte(s, val >> 8);
262
}
263

    
264
void put_be16(ByteIOContext *s, unsigned int val)
265
{
266
    put_byte(s, val >> 8);
267
    put_byte(s, val);
268
}
269

    
270
void put_le24(ByteIOContext *s, unsigned int val)
271
{
272
    put_le16(s, val & 0xffff);
273
    put_byte(s, val >> 16);
274
}
275

    
276
void put_be24(ByteIOContext *s, unsigned int val)
277
{
278
    put_be16(s, val >> 8);
279
    put_byte(s, val);
280
}
281

    
282
void put_tag(ByteIOContext *s, const char *tag)
283
{
284
    while (*tag) {
285
        put_byte(s, *tag++);
286
    }
287
}
288

    
289
/* Input stream */
290

    
291
static void fill_buffer(ByteIOContext *s)
292
{
293
    int len=0;
294

    
295
    /* no need to do anything if EOF already reached */
296
    if (s->eof_reached)
297
        return;
298

    
299
    if(s->update_checksum){
300
        if(s->buf_end > s->checksum_ptr)
301
            s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
302
        s->checksum_ptr= s->buffer;
303
    }
304

    
305
    if(s->read_packet)
306
        len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
307
    if (len <= 0) {
308
        /* do not modify buffer if EOF reached so that a seek back can
309
           be done without rereading data */
310
        s->eof_reached = 1;
311
        if(len<0)
312
            s->error= len;
313
    } else {
314
        s->pos += len;
315
        s->buf_ptr = s->buffer;
316
        s->buf_end = s->buffer + len;
317
    }
318
}
319

    
320
unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf, unsigned int len){
321
    return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
322
}
323

    
324
unsigned long get_checksum(ByteIOContext *s){
325
    s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
326
    s->update_checksum= NULL;
327
    return s->checksum;
328
}
329

    
330
void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){
331
    s->update_checksum= update_checksum;
332
    if(s->update_checksum){
333
        s->checksum= checksum;
334
        s->checksum_ptr= s->buf_ptr;
335
    }
336
}
337

    
338
/* XXX: put an inline version */
339
int get_byte(ByteIOContext *s)
340
{
341
    if (s->buf_ptr < s->buf_end) {
342
        return *s->buf_ptr++;
343
    } else {
344
        fill_buffer(s);
345
        if (s->buf_ptr < s->buf_end)
346
            return *s->buf_ptr++;
347
        else
348
            return 0;
349
    }
350
}
351

    
352
int url_fgetc(ByteIOContext *s)
353
{
354
    if (s->buf_ptr < s->buf_end) {
355
        return *s->buf_ptr++;
356
    } else {
357
        fill_buffer(s);
358
        if (s->buf_ptr < s->buf_end)
359
            return *s->buf_ptr++;
360
        else
361
            return URL_EOF;
362
    }
363
}
364

    
365
int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
366
{
367
    int len, size1;
368

    
369
    size1 = size;
370
    while (size > 0) {
371
        len = s->buf_end - s->buf_ptr;
372
        if (len > size)
373
            len = size;
374
        if (len == 0) {
375
            if(size > s->buffer_size && !s->update_checksum){
376
                if(s->read_packet)
377
                    len = s->read_packet(s->opaque, buf, size);
378
                if (len <= 0) {
379
                    /* do not modify buffer if EOF reached so that a seek back can
380
                    be done without rereading data */
381
                    s->eof_reached = 1;
382
                    if(len<0)
383
                        s->error= len;
384
                    break;
385
                } else {
386
                    s->pos += len;
387
                    size -= len;
388
                    buf += len;
389
                    s->buf_ptr = s->buffer;
390
                    s->buf_end = s->buffer/* + len*/;
391
                }
392
            }else{
393
                fill_buffer(s);
394
                len = s->buf_end - s->buf_ptr;
395
                if (len == 0)
396
                    break;
397
            }
398
        } else {
399
            memcpy(buf, s->buf_ptr, len);
400
            buf += len;
401
            s->buf_ptr += len;
402
            size -= len;
403
        }
404
    }
405
    return size1 - size;
406
}
407

    
408
int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
409
{
410
    int len;
411

    
412
    if(size<0)
413
        return -1;
414

    
415
    len = s->buf_end - s->buf_ptr;
416
    if (len == 0) {
417
        fill_buffer(s);
418
        len = s->buf_end - s->buf_ptr;
419
    }
420
    if (len > size)
421
        len = size;
422
    memcpy(buf, s->buf_ptr, len);
423
    s->buf_ptr += len;
424
    return len;
425
}
426

    
427
unsigned int get_le16(ByteIOContext *s)
428
{
429
    unsigned int val;
430
    val = get_byte(s);
431
    val |= get_byte(s) << 8;
432
    return val;
433
}
434

    
435
unsigned int get_le24(ByteIOContext *s)
436
{
437
    unsigned int val;
438
    val = get_le16(s);
439
    val |= get_byte(s) << 16;
440
    return val;
441
}
442

    
443
unsigned int get_le32(ByteIOContext *s)
444
{
445
    unsigned int val;
446
    val = get_le16(s);
447
    val |= get_le16(s) << 16;
448
    return val;
449
}
450

    
451
uint64_t get_le64(ByteIOContext *s)
452
{
453
    uint64_t val;
454
    val = (uint64_t)get_le32(s);
455
    val |= (uint64_t)get_le32(s) << 32;
456
    return val;
457
}
458

    
459
unsigned int get_be16(ByteIOContext *s)
460
{
461
    unsigned int val;
462
    val = get_byte(s) << 8;
463
    val |= get_byte(s);
464
    return val;
465
}
466

    
467
unsigned int get_be24(ByteIOContext *s)
468
{
469
    unsigned int val;
470
    val = get_be16(s) << 8;
471
    val |= get_byte(s);
472
    return val;
473
}
474
unsigned int get_be32(ByteIOContext *s)
475
{
476
    unsigned int val;
477
    val = get_be16(s) << 16;
478
    val |= get_be16(s);
479
    return val;
480
}
481

    
482
char *get_strz(ByteIOContext *s, char *buf, int maxlen)
483
{
484
    int i = 0;
485
    char c;
486

    
487
    while ((c = get_byte(s))) {
488
        if (i < maxlen-1)
489
            buf[i++] = c;
490
    }
491

    
492
    buf[i] = 0; /* Ensure null terminated, but may be truncated */
493

    
494
    return buf;
495
}
496

    
497
uint64_t get_be64(ByteIOContext *s)
498
{
499
    uint64_t val;
500
    val = (uint64_t)get_be32(s) << 32;
501
    val |= (uint64_t)get_be32(s);
502
    return val;
503
}
504

    
505
uint64_t ff_get_v(ByteIOContext *bc){
506
    uint64_t val = 0;
507
    int tmp;
508

    
509
    do{
510
        tmp = get_byte(bc);
511
        val= (val<<7) + (tmp&127);
512
    }while(tmp&128);
513
    return val;
514
}
515

    
516
int url_fdopen(ByteIOContext **s, URLContext *h)
517
{
518
    uint8_t *buffer;
519
    int buffer_size, max_packet_size;
520

    
521

    
522
    max_packet_size = url_get_max_packet_size(h);
523
    if (max_packet_size) {
524
        buffer_size = max_packet_size; /* no need to bufferize more than one packet */
525
    } else {
526
        buffer_size = IO_BUFFER_SIZE;
527
    }
528
    buffer = av_malloc(buffer_size);
529
    if (!buffer)
530
        return AVERROR(ENOMEM);
531

    
532
    *s = av_mallocz(sizeof(ByteIOContext));
533
    if(!*s) {
534
        av_free(buffer);
535
        return AVERROR(ENOMEM);
536
    }
537

    
538
    if (init_put_byte(*s, buffer, buffer_size,
539
                      (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
540
                      url_read, url_write, url_seek) < 0) {
541
        av_free(buffer);
542
        av_freep(s);
543
        return AVERROR(EIO);
544
    }
545
    (*s)->is_streamed = h->is_streamed;
546
    (*s)->max_packet_size = max_packet_size;
547
    if(h->prot) {
548
        (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
549
        (*s)->read_seek  = (offset_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
550
    }
551
    return 0;
552
}
553

    
554
int url_setbufsize(ByteIOContext *s, int buf_size)
555
{
556
    uint8_t *buffer;
557
    buffer = av_malloc(buf_size);
558
    if (!buffer)
559
        return AVERROR(ENOMEM);
560

    
561
    av_free(s->buffer);
562
    s->buffer = buffer;
563
    s->buffer_size = buf_size;
564
    s->buf_ptr = buffer;
565
    url_resetbuf(s, s->write_flag ? URL_WRONLY : URL_RDONLY);
566
    return 0;
567
}
568

    
569
int url_resetbuf(ByteIOContext *s, int flags)
570
{
571
    URLContext *h = s->opaque;
572
    if ((flags & URL_RDWR) || (h && h->flags != flags && !h->flags & URL_RDWR))
573
        return AVERROR(EINVAL);
574

    
575
    if (flags & URL_WRONLY) {
576
        s->buf_end = s->buffer + s->buffer_size;
577
        s->write_flag = 1;
578
    } else {
579
        s->buf_end = s->buffer;
580
        s->write_flag = 0;
581
    }
582
    return 0;
583
}
584

    
585
int url_fopen(ByteIOContext **s, const char *filename, int flags)
586
{
587
    URLContext *h;
588
    int err;
589

    
590
    err = url_open(&h, filename, flags);
591
    if (err < 0)
592
        return err;
593
    err = url_fdopen(s, h);
594
    if (err < 0) {
595
        url_close(h);
596
        return err;
597
    }
598
    return 0;
599
}
600

    
601
int url_fclose(ByteIOContext *s)
602
{
603
    URLContext *h = s->opaque;
604

    
605
    av_free(s->buffer);
606
    av_free(s);
607
    return url_close(h);
608
}
609

    
610
URLContext *url_fileno(ByteIOContext *s)
611
{
612
    return s->opaque;
613
}
614

    
615
#ifdef CONFIG_MUXERS
616
int url_fprintf(ByteIOContext *s, const char *fmt, ...)
617
{
618
    va_list ap;
619
    char buf[4096];
620
    int ret;
621

    
622
    va_start(ap, fmt);
623
    ret = vsnprintf(buf, sizeof(buf), fmt, ap);
624
    va_end(ap);
625
    put_buffer(s, buf, strlen(buf));
626
    return ret;
627
}
628
#endif //CONFIG_MUXERS
629

    
630
char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
631
{
632
    int c;
633
    char *q;
634

    
635
    c = url_fgetc(s);
636
    if (c == EOF)
637
        return NULL;
638
    q = buf;
639
    for(;;) {
640
        if (c == EOF || c == '\n')
641
            break;
642
        if ((q - buf) < buf_size - 1)
643
            *q++ = c;
644
        c = url_fgetc(s);
645
    }
646
    if (buf_size > 0)
647
        *q = '\0';
648
    return buf;
649
}
650

    
651
int url_fget_max_packet_size(ByteIOContext *s)
652
{
653
    return s->max_packet_size;
654
}
655

    
656
int av_url_read_fpause(ByteIOContext *s, int pause)
657
{
658
    if (!s->read_pause)
659
        return AVERROR(ENOSYS);
660
    return s->read_pause(s->opaque, pause);
661
}
662

    
663
offset_t av_url_read_fseek(ByteIOContext *s,
664
        int stream_index, int64_t timestamp, int flags)
665
{
666
    URLContext *h = s->opaque;
667
    offset_t ret;
668
    if (!s->read_seek)
669
        return AVERROR(ENOSYS);
670
    ret = s->read_seek(h, stream_index, timestamp, flags);
671
    if(ret >= 0) {
672
        s->buf_ptr = s->buf_end; // Flush buffer
673
        s->pos = s->seek(h, 0, SEEK_CUR);
674
    }
675
    return ret;
676
}
677

    
678
/* url_open_dyn_buf and url_close_dyn_buf are used in rtp.c to send a response
679
 * back to the server even if CONFIG_MUXERS is not set. */
680
#if defined(CONFIG_MUXERS) || defined(CONFIG_NETWORK)
681
/* buffer handling */
682
int url_open_buf(ByteIOContext **s, uint8_t *buf, int buf_size, int flags)
683
{
684
    int ret;
685
    *s = av_mallocz(sizeof(ByteIOContext));
686
    if(!*s)
687
        return AVERROR(ENOMEM);
688
    ret = init_put_byte(*s, buf, buf_size,
689
                        (flags & URL_WRONLY || flags & URL_RDWR),
690
                        NULL, NULL, NULL, NULL);
691
    if(ret != 0)
692
        av_freep(s);
693
    return ret;
694
}
695

    
696
int url_close_buf(ByteIOContext *s)
697
{
698
    put_flush_packet(s);
699
    return s->buf_ptr - s->buffer;
700
}
701

    
702
/* output in a dynamic buffer */
703

    
704
typedef struct DynBuffer {
705
    int pos, size, allocated_size;
706
    uint8_t *buffer;
707
    int io_buffer_size;
708
    uint8_t io_buffer[1];
709
} DynBuffer;
710

    
711
static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
712
{
713
    DynBuffer *d = opaque;
714
    int new_size, new_allocated_size;
715

    
716
    /* reallocate buffer if needed */
717
    new_size = d->pos + buf_size;
718
    new_allocated_size = d->allocated_size;
719
    if(new_size < d->pos || new_size > INT_MAX/2)
720
        return -1;
721
    while (new_size > new_allocated_size) {
722
        if (!new_allocated_size)
723
            new_allocated_size = new_size;
724
        else
725
            new_allocated_size += new_allocated_size / 2 + 1;
726
    }
727

    
728
    if (new_allocated_size > d->allocated_size) {
729
        d->buffer = av_realloc(d->buffer, new_allocated_size);
730
        if(d->buffer == NULL)
731
             return -1234;
732
        d->allocated_size = new_allocated_size;
733
    }
734
    memcpy(d->buffer + d->pos, buf, buf_size);
735
    d->pos = new_size;
736
    if (d->pos > d->size)
737
        d->size = d->pos;
738
    return buf_size;
739
}
740

    
741
static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
742
{
743
    unsigned char buf1[4];
744
    int ret;
745

    
746
    /* packetized write: output the header */
747
    buf1[0] = (buf_size >> 24);
748
    buf1[1] = (buf_size >> 16);
749
    buf1[2] = (buf_size >> 8);
750
    buf1[3] = (buf_size);
751
    ret= dyn_buf_write(opaque, buf1, 4);
752
    if(ret < 0)
753
        return ret;
754

    
755
    /* then the data */
756
    return dyn_buf_write(opaque, buf, buf_size);
757
}
758

    
759
static offset_t dyn_buf_seek(void *opaque, offset_t offset, int whence)
760
{
761
    DynBuffer *d = opaque;
762

    
763
    if (whence == SEEK_CUR)
764
        offset += d->pos;
765
    else if (whence == SEEK_END)
766
        offset += d->size;
767
    if (offset < 0 || offset > 0x7fffffffLL)
768
        return -1;
769
    d->pos = offset;
770
    return 0;
771
}
772

    
773
static int url_open_dyn_buf_internal(ByteIOContext **s, int max_packet_size)
774
{
775
    DynBuffer *d;
776
    int io_buffer_size, ret;
777

    
778
    if (max_packet_size)
779
        io_buffer_size = max_packet_size;
780
    else
781
        io_buffer_size = 1024;
782

    
783
    if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
784
        return -1;
785
    d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
786
    if (!d)
787
        return -1;
788
    *s = av_mallocz(sizeof(ByteIOContext));
789
    if(!*s) {
790
        av_free(d);
791
        return AVERROR(ENOMEM);
792
    }
793
    d->io_buffer_size = io_buffer_size;
794
    d->buffer = NULL;
795
    d->pos = 0;
796
    d->size = 0;
797
    d->allocated_size = 0;
798
    ret = init_put_byte(*s, d->io_buffer, io_buffer_size,
799
                        1, d, NULL,
800
                        max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
801
                        max_packet_size ? NULL : dyn_buf_seek);
802
    if (ret == 0) {
803
        (*s)->max_packet_size = max_packet_size;
804
    } else {
805
        av_free(d);
806
        av_freep(s);
807
    }
808
    return ret;
809
}
810

    
811
int url_open_dyn_buf(ByteIOContext **s)
812
{
813
    return url_open_dyn_buf_internal(s, 0);
814
}
815

    
816
int url_open_dyn_packet_buf(ByteIOContext **s, int max_packet_size)
817
{
818
    if (max_packet_size <= 0)
819
        return -1;
820
    return url_open_dyn_buf_internal(s, max_packet_size);
821
}
822

    
823
int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
824
{
825
    DynBuffer *d = s->opaque;
826
    int size;
827

    
828
    put_flush_packet(s);
829

    
830
    *pbuffer = d->buffer;
831
    size = d->size;
832
    av_free(d);
833
    av_free(s);
834
    return size;
835
}
836
#endif /* CONFIG_MUXERS || CONFIG_NETWORK */