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ffmpeg / libavformat / aviobuf.c @ 764ef400

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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
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 * 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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                  void (*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;
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    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->is_streamed = 0;
50
    s->max_packet_size = 0;
51
    return 0;
52
}
53
                  
54

    
55
#ifdef CONFIG_ENCODERS
56
static void flush_buffer(ByteIOContext *s)
57
{
58
    if (s->buf_ptr > s->buffer) {
59
        if (s->write_packet)
60
            s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
61
        s->pos += s->buf_ptr - s->buffer;
62
    }
63
    s->buf_ptr = s->buffer;
64
}
65

    
66
void put_byte(ByteIOContext *s, int b)
67
{
68
    *(s->buf_ptr)++ = b;
69
    if (s->buf_ptr >= s->buf_end) 
70
        flush_buffer(s);
71
}
72

    
73
void put_buffer(ByteIOContext *s, const unsigned char *buf, int size)
74
{
75
    int len;
76

    
77
    while (size > 0) {
78
        len = (s->buf_end - s->buf_ptr);
79
        if (len > size)
80
            len = size;
81
        memcpy(s->buf_ptr, buf, len);
82
        s->buf_ptr += len;
83

    
84
        if (s->buf_ptr >= s->buf_end) 
85
            flush_buffer(s);
86

    
87
        buf += len;
88
        size -= len;
89
    }
90
}
91

    
92
void put_flush_packet(ByteIOContext *s)
93
{
94
    flush_buffer(s);
95
    s->must_flush = 0;
96
}
97
#endif //CONFIG_ENCODERS
98

    
99
offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence)
100
{
101
    offset_t offset1;
102

    
103
    if (whence != SEEK_CUR && whence != SEEK_SET)
104
        return -EINVAL;
105
    
106
#ifdef CONFIG_ENCODERS
107
    if (s->write_flag) {
108
        if (whence == SEEK_CUR) {
109
            offset1 = s->pos + (s->buf_ptr - s->buffer);
110
            if (offset == 0)
111
                return offset1;
112
            offset += offset1;
113
        }
114
        offset1 = offset - s->pos;
115
        if (!s->must_flush && 
116
            offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) {
117
            /* can do the seek inside the buffer */
118
            s->buf_ptr = s->buffer + offset1;
119
        } else {
120
            if (!s->seek)
121
                return -EPIPE;
122
            flush_buffer(s);
123
            s->must_flush = 1;
124
            s->buf_ptr = s->buffer;
125
            s->seek(s->opaque, offset, SEEK_SET);
126
            s->pos = offset;
127
        }
128
    } else 
129
#endif //CONFIG_ENCODERS
130
    {
131
        if (whence == SEEK_CUR) {
132
            offset1 = s->pos - (s->buf_end - s->buffer) + (s->buf_ptr - s->buffer);
133
            if (offset == 0)
134
                return offset1;
135
            offset += offset1;
136
        }
137
        offset1 = offset - (s->pos - (s->buf_end - s->buffer));
138
        if (offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
139
            /* can do the seek inside the buffer */
140
            s->buf_ptr = s->buffer + offset1;
141
        } else {
142
            if (!s->seek)
143
                return -EPIPE;
144
            s->buf_ptr = s->buffer;
145
            s->buf_end = s->buffer;
146
            s->seek(s->opaque, offset, SEEK_SET);
147
            s->pos = offset;
148
        }
149
        s->eof_reached = 0;
150
    }
151
    return offset;
152
}
153

    
154
void url_fskip(ByteIOContext *s, offset_t offset)
155
{
156
    url_fseek(s, offset, SEEK_CUR);
157
}
158

    
159
offset_t url_ftell(ByteIOContext *s)
160
{
161
    return url_fseek(s, 0, SEEK_CUR);
162
}
163

    
164
int url_feof(ByteIOContext *s)
165
{
166
    return s->eof_reached;
167
}
168

    
169
#ifdef CONFIG_ENCODERS
170
void put_le32(ByteIOContext *s, unsigned int val)
171
{
172
    put_byte(s, val);
173
    put_byte(s, val >> 8);
174
    put_byte(s, val >> 16);
175
    put_byte(s, val >> 24);
176
}
177

    
178
void put_be32(ByteIOContext *s, unsigned int val)
179
{
180
    put_byte(s, val >> 24);
181
    put_byte(s, val >> 16);
182
    put_byte(s, val >> 8);
183
    put_byte(s, val);
184
}
185

    
186
/* IEEE format is assumed */
187
void put_be64_double(ByteIOContext *s, double val)
188
{
189
    union {
190
        double d;
191
        uint64_t ull;
192
    } u;
193
    u.d = val;
194
    put_be64(s, u.ull);
195
}
196

    
197
void put_strz(ByteIOContext *s, const char *str)
198
{
199
    if (str)
200
        put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
201
    else
202
        put_byte(s, 0);
203
}
204

    
205
void put_le64(ByteIOContext *s, uint64_t val)
206
{
207
    put_le32(s, (uint32_t)(val & 0xffffffff));
208
    put_le32(s, (uint32_t)(val >> 32));
209
}
210

    
211
void put_be64(ByteIOContext *s, uint64_t val)
212
{
213
    put_be32(s, (uint32_t)(val >> 32));
214
    put_be32(s, (uint32_t)(val & 0xffffffff));
215
}
216

    
217
void put_le16(ByteIOContext *s, unsigned int val)
218
{
219
    put_byte(s, val);
220
    put_byte(s, val >> 8);
221
}
222

    
223
void put_be16(ByteIOContext *s, unsigned int val)
224
{
225
    put_byte(s, val >> 8);
226
    put_byte(s, val);
227
}
228

    
229
void put_tag(ByteIOContext *s, const char *tag)
230
{
231
    while (*tag) {
232
        put_byte(s, *tag++);
233
    }
234
}
235
#endif //CONFIG_ENCODERS
236

    
237
/* Input stream */
238

    
239
static void fill_buffer(ByteIOContext *s)
240
{
241
    int len;
242

    
243
    /* no need to do anything if EOF already reached */
244
    if (s->eof_reached)
245
        return;
246
    len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
247
    if (len <= 0) {
248
        /* do not modify buffer if EOF reached so that a seek back can
249
           be done without rereading data */
250
        s->eof_reached = 1;
251
    } else {
252
        s->pos += len;
253
        s->buf_ptr = s->buffer;
254
        s->buf_end = s->buffer + len;
255
    }
256
}
257

    
258
/* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
259
   necessary */
260
/* XXX: put an inline version */
261
int get_byte(ByteIOContext *s)
262
{
263
    if (s->buf_ptr < s->buf_end) {
264
        return *s->buf_ptr++;
265
    } else {
266
        fill_buffer(s);
267
        if (s->buf_ptr < s->buf_end)
268
            return *s->buf_ptr++;
269
        else
270
            return 0;
271
    }
272
}
273

    
274
/* NOTE: return URL_EOF (-1) if EOF */
275
int url_fgetc(ByteIOContext *s)
276
{
277
    if (s->buf_ptr < s->buf_end) {
278
        return *s->buf_ptr++;
279
    } else {
280
        fill_buffer(s);
281
        if (s->buf_ptr < s->buf_end)
282
            return *s->buf_ptr++;
283
        else
284
            return URL_EOF;
285
    }
286
}
287

    
288
int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
289
{
290
    int len, size1;
291

    
292
    size1 = size;
293
    while (size > 0) {
294
        len = s->buf_end - s->buf_ptr;
295
        if (len > size)
296
            len = size;
297
        if (len == 0) {
298
            fill_buffer(s);
299
            len = s->buf_end - s->buf_ptr;
300
            if (len == 0)
301
                break;
302
        } else {
303
            memcpy(buf, s->buf_ptr, len);
304
            buf += len;
305
            s->buf_ptr += len;
306
            size -= len;
307
        }
308
    }
309
    return size1 - size;
310
}
311

    
312
unsigned int get_le16(ByteIOContext *s)
313
{
314
    unsigned int val;
315
    val = get_byte(s);
316
    val |= get_byte(s) << 8;
317
    return val;
318
}
319

    
320
unsigned int get_le32(ByteIOContext *s)
321
{
322
    unsigned int val;
323
    val = get_byte(s);
324
    val |= get_byte(s) << 8;
325
    val |= get_byte(s) << 16;
326
    val |= get_byte(s) << 24;
327
    return val;
328
}
329

    
330
uint64_t get_le64(ByteIOContext *s)
331
{
332
    uint64_t val;
333
    val = (uint64_t)get_le32(s);
334
    val |= (uint64_t)get_le32(s) << 32;
335
    return val;
336
}
337

    
338
unsigned int get_be16(ByteIOContext *s)
339
{
340
    unsigned int val;
341
    val = get_byte(s) << 8;
342
    val |= get_byte(s);
343
    return val;
344
}
345

    
346
unsigned int get_be32(ByteIOContext *s)
347
{
348
    unsigned int val;
349
    val = get_byte(s) << 24;
350
    val |= get_byte(s) << 16;
351
    val |= get_byte(s) << 8;
352
    val |= get_byte(s);
353
    return val;
354
}
355

    
356
double get_be64_double(ByteIOContext *s)
357
{
358
    union {
359
        double d;
360
        uint64_t ull;
361
    } u;
362

    
363
    u.ull = get_be64(s);
364
    return u.d;
365
}
366

    
367
char *get_strz(ByteIOContext *s, char *buf, int maxlen)
368
{
369
    int i = 0;
370
    char c;
371

    
372
    while ((c = get_byte(s))) {
373
        if (i < maxlen-1)
374
            buf[i++] = c;
375
    }
376
    
377
    buf[i] = 0; /* Ensure null terminated, but may be truncated */
378

    
379
    return buf;
380
}
381

    
382
uint64_t get_be64(ByteIOContext *s)
383
{
384
    uint64_t val;
385
    val = (uint64_t)get_be32(s) << 32;
386
    val |= (uint64_t)get_be32(s);
387
    return val;
388
}
389

    
390
/* link with avio functions */
391

    
392
#ifdef CONFIG_ENCODERS
393
static void url_write_packet(void *opaque, uint8_t *buf, int buf_size)
394
{
395
    URLContext *h = opaque;
396
    url_write(h, buf, buf_size);
397
}
398
#else
399
#define        url_write_packet NULL
400
#endif //CONFIG_ENCODERS
401

    
402
static int url_read_packet(void *opaque, uint8_t *buf, int buf_size)
403
{
404
    URLContext *h = opaque;
405
    return url_read(h, buf, buf_size);
406
}
407

    
408
static int url_seek_packet(void *opaque, int64_t offset, int whence)
409
{
410
    URLContext *h = opaque;
411
    url_seek(h, offset, whence);
412
    return 0;
413
}
414

    
415
int url_fdopen(ByteIOContext *s, URLContext *h)
416
{
417
    uint8_t *buffer;
418
    int buffer_size, max_packet_size;
419

    
420
    
421
    max_packet_size = url_get_max_packet_size(h);
422
    if (max_packet_size) {
423
        buffer_size = max_packet_size; /* no need to bufferize more than one packet */
424
    } else {
425
        buffer_size = IO_BUFFER_SIZE;
426
    }
427
    buffer = av_malloc(buffer_size);
428
    if (!buffer)
429
        return -ENOMEM;
430

    
431
    if (init_put_byte(s, buffer, buffer_size, 
432
                      (h->flags & URL_WRONLY) != 0, h,
433
                      url_read_packet, url_write_packet, url_seek_packet) < 0) {
434
        av_free(buffer);
435
        return -EIO;
436
    }
437
    s->is_streamed = h->is_streamed;
438
    s->max_packet_size = max_packet_size;
439
    return 0;
440
}
441

    
442
/* XXX: must be called before any I/O */
443
int url_setbufsize(ByteIOContext *s, int buf_size)
444
{
445
    uint8_t *buffer;
446
    buffer = av_malloc(buf_size);
447
    if (!buffer)
448
        return -ENOMEM;
449

    
450
    av_free(s->buffer);
451
    s->buffer = buffer;
452
    s->buffer_size = buf_size;
453
    s->buf_ptr = buffer;
454
    if (!s->write_flag) 
455
        s->buf_end = buffer;
456
    else
457
        s->buf_end = buffer + buf_size;
458
    return 0;
459
}
460

    
461
/* NOTE: when opened as read/write, the buffers are only used for
462
   reading */
463
int url_fopen(ByteIOContext *s, const char *filename, int flags)
464
{
465
    URLContext *h;
466
    int err;
467

    
468
    err = url_open(&h, filename, flags);
469
    if (err < 0)
470
        return err;
471
    err = url_fdopen(s, h);
472
    if (err < 0) {
473
        url_close(h);
474
        return err;
475
    }
476
    return 0;
477
}
478

    
479
int url_fclose(ByteIOContext *s)
480
{
481
    URLContext *h = s->opaque;
482
    
483
    av_free(s->buffer);
484
    memset(s, 0, sizeof(ByteIOContext));
485
    return url_close(h);
486
}
487

    
488
URLContext *url_fileno(ByteIOContext *s)
489
{
490
    return s->opaque;
491
}
492

    
493
#ifdef CONFIG_ENCODERS
494
/* XXX: currently size is limited */
495
int url_fprintf(ByteIOContext *s, const char *fmt, ...)
496
{
497
    va_list ap;
498
    char buf[4096];
499
    int ret;
500

    
501
    va_start(ap, fmt);
502
    ret = vsnprintf(buf, sizeof(buf), fmt, ap);
503
    va_end(ap);
504
    put_buffer(s, buf, strlen(buf));
505
    return ret;
506
}
507
#endif //CONFIG_ENCODERS
508

    
509
/* note: unlike fgets, the EOL character is not returned and a whole
510
   line is parsed. return NULL if first char read was EOF */
511
char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
512
{
513
    int c;
514
    char *q;
515

    
516
    c = url_fgetc(s);
517
    if (c == EOF)
518
        return NULL;
519
    q = buf;
520
    for(;;) {
521
        if (c == EOF || c == '\n')
522
            break;
523
        if ((q - buf) < buf_size - 1)
524
            *q++ = c;
525
        c = url_fgetc(s);
526
    }
527
    if (buf_size > 0)
528
        *q = '\0';
529
    return buf;
530
}
531

    
532
/* 
533
 * Return the maximum packet size associated to packetized buffered file
534
 * handle. If the file is not packetized (stream like http or file on
535
 * disk), then 0 is returned.
536
 * 
537
 * @param h buffered file handle
538
 * @return maximum packet size in bytes
539
 */
540
int url_fget_max_packet_size(ByteIOContext *s)
541
{
542
    return s->max_packet_size;
543
}
544

    
545
#ifdef CONFIG_ENCODERS
546
/* buffer handling */
547
int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags)
548
{
549
    return init_put_byte(s, buf, buf_size, 
550
                         (flags & URL_WRONLY) != 0, NULL, NULL, NULL, NULL);
551
}
552

    
553
/* return the written or read size */
554
int url_close_buf(ByteIOContext *s)
555
{
556
    put_flush_packet(s);
557
    return s->buf_ptr - s->buffer;
558
}
559

    
560
/* output in a dynamic buffer */
561

    
562
typedef struct DynBuffer {
563
    int pos, size, allocated_size;
564
    uint8_t *buffer;
565
    int io_buffer_size;
566
    uint8_t io_buffer[1];
567
} DynBuffer;
568

    
569
static void dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
570
{
571
    DynBuffer *d = opaque;
572
    int new_size, new_allocated_size;
573
    
574
    /* reallocate buffer if needed */
575
    new_size = d->pos + buf_size;
576
    new_allocated_size = d->allocated_size;
577
    while (new_size > new_allocated_size) {
578
        if (!new_allocated_size)
579
            new_allocated_size = new_size;
580
        else
581
            new_allocated_size = (new_allocated_size * 3) / 2 + 1;    
582
    }
583
    
584
    if (new_allocated_size > d->allocated_size) {
585
        d->buffer = av_realloc(d->buffer, new_allocated_size);
586
        if(d->buffer == NULL)
587
             return ;
588
        d->allocated_size = new_allocated_size;
589
    }
590
    memcpy(d->buffer + d->pos, buf, buf_size);
591
    d->pos = new_size;
592
    if (d->pos > d->size)
593
        d->size = d->pos;
594
}
595

    
596
static void dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
597
{
598
    unsigned char buf1[4];
599

    
600
    /* packetized write: output the header */
601
    buf1[0] = (buf_size >> 24);
602
    buf1[1] = (buf_size >> 16);
603
    buf1[2] = (buf_size >> 8);
604
    buf1[3] = (buf_size);
605
    dyn_buf_write(opaque, buf1, 4);
606

    
607
    /* then the data */
608
    dyn_buf_write(opaque, buf, buf_size);
609
}
610

    
611
static int dyn_buf_seek(void *opaque, offset_t offset, int whence)
612
{
613
    DynBuffer *d = opaque;
614

    
615
    if (whence == SEEK_CUR)
616
        offset += d->pos;
617
    else if (whence == SEEK_END)
618
        offset += d->size;
619
    if (offset < 0 || offset > 0x7fffffffLL)
620
        return -1;
621
    d->pos = offset;
622
    return 0;
623
}
624

    
625
static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
626
{
627
    DynBuffer *d;
628
    int io_buffer_size, ret;
629
    
630
    if (max_packet_size) 
631
        io_buffer_size = max_packet_size;
632
    else
633
        io_buffer_size = 1024;
634
        
635
    d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
636
    if (!d)
637
        return -1;
638
    d->io_buffer_size = io_buffer_size;
639
    d->buffer = NULL;
640
    d->pos = 0;
641
    d->size = 0;
642
    d->allocated_size = 0;
643
    ret = init_put_byte(s, d->io_buffer, io_buffer_size, 
644
                        1, d, NULL, 
645
                        max_packet_size ? dyn_packet_buf_write : dyn_buf_write, 
646
                        max_packet_size ? NULL : dyn_buf_seek);
647
    if (ret == 0) {
648
        s->max_packet_size = max_packet_size;
649
    }
650
    return ret;
651
}
652

    
653
/*
654
 * Open a write only memory stream.
655
 * 
656
 * @param s new IO context
657
 * @return zero if no error.
658
 */
659
int url_open_dyn_buf(ByteIOContext *s)
660
{
661
    return url_open_dyn_buf_internal(s, 0);
662
}
663

    
664
/*
665
 * Open a write only packetized memory stream with a maximum packet
666
 * size of 'max_packet_size'.  The stream is stored in a memory buffer
667
 * with a big endian 4 byte header giving the packet size in bytes.
668
 * 
669
 * @param s new IO context
670
 * @param max_packet_size maximum packet size (must be > 0) 
671
 * @return zero if no error.
672
 */
673
int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
674
{
675
    if (max_packet_size <= 0)
676
        return -1;
677
    return url_open_dyn_buf_internal(s, max_packet_size);
678
}
679

    
680
/* 
681
 * Return the written size and a pointer to the buffer. The buffer
682
 *  must be freed with av_free(). 
683
 * @param s IO context
684
 * @param pointer to a byte buffer
685
 * @return the length of the byte buffer
686
 */
687
int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
688
{
689
    DynBuffer *d = s->opaque;
690
    int size;
691

    
692
    put_flush_packet(s);
693

    
694
    *pbuffer = d->buffer;
695
    size = d->size;
696
    av_free(d);
697
    return size;
698
}
699
#endif //CONFIG_ENCODERS