aboutsummaryrefslogtreecommitdiffstats
path: root/libavformat/aviobuf.c
blob: bb55254532a6e136aa6a413b1dc9dc1d3c4d9068 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
/*
 * Buffered I/O for ffmpeg system
 * Copyright (c) 2000,2001 Fabrice Bellard
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include "avformat.h"
#include "avio.h"
#include <stdarg.h>

#define IO_BUFFER_SIZE 32768

int init_put_byte(ByteIOContext *s,
                  unsigned char *buffer,
                  int buffer_size,
                  int write_flag,
                  void *opaque,
                  int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
                  int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
                  int (*seek)(void *opaque, offset_t offset, int whence))
{
    s->buffer = buffer;
    s->buffer_size = buffer_size;
    s->buf_ptr = buffer;
    s->write_flag = write_flag;
    if (!s->write_flag) 
        s->buf_end = buffer;
    else
        s->buf_end = buffer + buffer_size;
    s->opaque = opaque;
    s->write_packet = write_packet;
    s->read_packet = read_packet;
    s->seek = seek;
    s->pos = 0;
    s->must_flush = 0;
    s->eof_reached = 0;
    s->error = 0;
    s->is_streamed = 0;
    s->max_packet_size = 0;
    s->update_checksum= NULL;
    return 0;
}
                  

#ifdef CONFIG_ENCODERS
static void flush_buffer(ByteIOContext *s)
{
    if (s->buf_ptr > s->buffer) {
        if (s->write_packet && !s->error){
            int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
            if(ret < 0){
                s->error = ret;
            }
        }
        if(s->update_checksum){
            s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
            s->checksum_ptr= s->buffer;
        }
        s->pos += s->buf_ptr - s->buffer;
    }
    s->buf_ptr = s->buffer;
}

void put_byte(ByteIOContext *s, int b)
{
    *(s->buf_ptr)++ = b;
    if (s->buf_ptr >= s->buf_end) 
        flush_buffer(s);
}

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

    while (size > 0) {
        len = (s->buf_end - s->buf_ptr);
        if (len > size)
            len = size;
        memcpy(s->buf_ptr, buf, len);
        s->buf_ptr += len;

        if (s->buf_ptr >= s->buf_end) 
            flush_buffer(s);

        buf += len;
        size -= len;
    }
}

void put_flush_packet(ByteIOContext *s)
{
    flush_buffer(s);
    s->must_flush = 0;
}
#endif //CONFIG_ENCODERS

offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence)
{
    offset_t offset1;

    if (whence != SEEK_CUR && whence != SEEK_SET)
        return -EINVAL;
    
#ifdef CONFIG_ENCODERS
    if (s->write_flag) {
        if (whence == SEEK_CUR) {
            offset1 = s->pos + (s->buf_ptr - s->buffer);
            if (offset == 0)
                return offset1;
            offset += offset1;
        }
        offset1 = offset - s->pos;
        if (!s->must_flush && 
            offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) {
            /* can do the seek inside the buffer */
            s->buf_ptr = s->buffer + offset1;
        } else {
            if (!s->seek)
                return -EPIPE;
            flush_buffer(s);
            s->must_flush = 1;
            s->buf_ptr = s->buffer;
            s->seek(s->opaque, offset, SEEK_SET);
            s->pos = offset;
        }
    } else 
#endif //CONFIG_ENCODERS
    {
        if (whence == SEEK_CUR) {
            offset1 = s->pos - (s->buf_end - s->buffer) + (s->buf_ptr - s->buffer);
            if (offset == 0)
                return offset1;
            offset += offset1;
        }
        offset1 = offset - (s->pos - (s->buf_end - s->buffer));
        if (offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
            /* can do the seek inside the buffer */
            s->buf_ptr = s->buffer + offset1;
        } else {
            if (!s->seek)
                return -EPIPE;
            s->buf_ptr = s->buffer;
            s->buf_end = s->buffer;
            if (s->seek(s->opaque, offset, SEEK_SET) == (offset_t)-EPIPE)
                return -EPIPE;
            s->pos = offset;
        }
        s->eof_reached = 0;
    }
    return offset;
}

void url_fskip(ByteIOContext *s, offset_t offset)
{
    url_fseek(s, offset, SEEK_CUR);
}

offset_t url_ftell(ByteIOContext *s)
{
    return url_fseek(s, 0, SEEK_CUR);
}

int url_feof(ByteIOContext *s)
{
    return s->eof_reached;
}

int url_ferror(ByteIOContext *s)
{
    return s->error;
}

#ifdef CONFIG_ENCODERS
void put_le32(ByteIOContext *s, unsigned int val)
{
    put_byte(s, val);
    put_byte(s, val >> 8);
    put_byte(s, val >> 16);
    put_byte(s, val >> 24);
}

void put_be32(ByteIOContext *s, unsigned int val)
{
    put_byte(s, val >> 24);
    put_byte(s, val >> 16);
    put_byte(s, val >> 8);
    put_byte(s, val);
}

/* IEEE format is assumed */
void put_be64_double(ByteIOContext *s, double val)
{
    union {
        double d;
        uint64_t ull;
    } u;
    u.d = val;
    put_be64(s, u.ull);
}

void put_strz(ByteIOContext *s, const char *str)
{
    if (str)
        put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
    else
        put_byte(s, 0);
}

void put_le64(ByteIOContext *s, uint64_t val)
{
    put_le32(s, (uint32_t)(val & 0xffffffff));
    put_le32(s, (uint32_t)(val >> 32));
}

void put_be64(ByteIOContext *s, uint64_t val)
{
    put_be32(s, (uint32_t)(val >> 32));
    put_be32(s, (uint32_t)(val & 0xffffffff));
}

void put_le16(ByteIOContext *s, unsigned int val)
{
    put_byte(s, val);
    put_byte(s, val >> 8);
}

void put_be16(ByteIOContext *s, unsigned int val)
{
    put_byte(s, val >> 8);
    put_byte(s, val);
}

void put_tag(ByteIOContext *s, const char *tag)
{
    while (*tag) {
        put_byte(s, *tag++);
    }
}
#endif //CONFIG_ENCODERS

/* Input stream */

static void fill_buffer(ByteIOContext *s)
{
    int len;

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

    if(s->update_checksum){
        s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
        s->checksum_ptr= s->buffer;
    }

    len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
    if (len <= 0) {
        /* do not modify buffer if EOF reached so that a seek back can
           be done without rereading data */
        s->eof_reached = 1;
    if(len<0)
        s->error= len;
    } else {
        s->pos += len;
        s->buf_ptr = s->buffer;
        s->buf_end = s->buffer + len;
    }
}

unsigned long get_checksum(ByteIOContext *s){
    s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
    s->update_checksum= NULL;
    return s->checksum;
}

void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){
    s->update_checksum= update_checksum;
    if(s->update_checksum){
        s->checksum= s->update_checksum(checksum, NULL, 0);
        s->checksum_ptr= s->buf_ptr;
    }
}

/* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
   necessary */
/* XXX: put an inline version */
int get_byte(ByteIOContext *s)
{
    if (s->buf_ptr < s->buf_end) {
        return *s->buf_ptr++;
    } else {
        fill_buffer(s);
        if (s->buf_ptr < s->buf_end)
            return *s->buf_ptr++;
        else
            return 0;
    }
}

/* NOTE: return URL_EOF (-1) if EOF */
int url_fgetc(ByteIOContext *s)
{
    if (s->buf_ptr < s->buf_end) {
        return *s->buf_ptr++;
    } else {
        fill_buffer(s);
        if (s->buf_ptr < s->buf_end)
            return *s->buf_ptr++;
        else
            return URL_EOF;
    }
}

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

    size1 = size;
    while (size > 0) {
        len = s->buf_end - s->buf_ptr;
        if (len > size)
            len = size;
        if (len == 0) {
            fill_buffer(s);
            len = s->buf_end - s->buf_ptr;
            if (len == 0)
                break;
        } else {
            memcpy(buf, s->buf_ptr, len);
            buf += len;
            s->buf_ptr += len;
            size -= len;
        }
    }
    return size1 - size;
}

int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
{
    int len;

    len = s->buf_end - s->buf_ptr;
    if (len == 0) {
        fill_buffer(s);
        len = s->buf_end - s->buf_ptr;
    }
    if (len > size)
        len = size;
    memcpy(buf, s->buf_ptr, len);
    s->buf_ptr += len;
    return len;
}

unsigned int get_le16(ByteIOContext *s)
{
    unsigned int val;
    val = get_byte(s);
    val |= get_byte(s) << 8;
    return val;
}

unsigned int get_le32(ByteIOContext *s)
{
    unsigned int val;
    val = get_byte(s);
    val |= get_byte(s) << 8;
    val |= get_byte(s) << 16;
    val |= get_byte(s) << 24;
    return val;
}

uint64_t get_le64(ByteIOContext *s)
{
    uint64_t val;
    val = (uint64_t)get_le32(s);
    val |= (uint64_t)get_le32(s) << 32;
    return val;
}

unsigned int get_be16(ByteIOContext *s)
{
    unsigned int val;
    val = get_byte(s) << 8;
    val |= get_byte(s);
    return val;
}

unsigned int get_be32(ByteIOContext *s)
{
    unsigned int val;
    val = get_byte(s) << 24;
    val |= get_byte(s) << 16;
    val |= get_byte(s) << 8;
    val |= get_byte(s);
    return val;
}

double get_be64_double(ByteIOContext *s)
{
    union {
        double d;
        uint64_t ull;
    } u;

    u.ull = get_be64(s);
    return u.d;
}

char *get_strz(ByteIOContext *s, char *buf, int maxlen)
{
    int i = 0;
    char c;

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

    return buf;
}

uint64_t get_be64(ByteIOContext *s)
{
    uint64_t val;
    val = (uint64_t)get_be32(s) << 32;
    val |= (uint64_t)get_be32(s);
    return val;
}

/* link with avio functions */

#ifdef CONFIG_ENCODERS
static int url_write_packet(void *opaque, uint8_t *buf, int buf_size)
{
    URLContext *h = opaque;
    return url_write(h, buf, buf_size);
}
#else
#define	url_write_packet NULL
#endif //CONFIG_ENCODERS

static int url_read_packet(void *opaque, uint8_t *buf, int buf_size)
{
    URLContext *h = opaque;
    return url_read(h, buf, buf_size);
}

static int url_seek_packet(void *opaque, int64_t offset, int whence)
{
    URLContext *h = opaque;
    return url_seek(h, offset, whence);
    //return 0;
}

int url_fdopen(ByteIOContext *s, URLContext *h)
{
    uint8_t *buffer;
    int buffer_size, max_packet_size;

    
    max_packet_size = url_get_max_packet_size(h);
    if (max_packet_size) {
        buffer_size = max_packet_size; /* no need to bufferize more than one packet */
    } else {
        buffer_size = IO_BUFFER_SIZE;
    }
    buffer = av_malloc(buffer_size);
    if (!buffer)
        return -ENOMEM;

    if (init_put_byte(s, buffer, buffer_size, 
                      (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
                      url_read_packet, url_write_packet, url_seek_packet) < 0) {
        av_free(buffer);
        return AVERROR_IO;
    }
    s->is_streamed = h->is_streamed;
    s->max_packet_size = max_packet_size;
    return 0;
}

/* XXX: must be called before any I/O */
int url_setbufsize(ByteIOContext *s, int buf_size)
{
    uint8_t *buffer;
    buffer = av_malloc(buf_size);
    if (!buffer)
        return -ENOMEM;

    av_free(s->buffer);
    s->buffer = buffer;
    s->buffer_size = buf_size;
    s->buf_ptr = buffer;
    if (!s->write_flag) 
        s->buf_end = buffer;
    else
        s->buf_end = buffer + buf_size;
    return 0;
}

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

    err = url_open(&h, filename, flags);
    if (err < 0)
        return err;
    err = url_fdopen(s, h);
    if (err < 0) {
        url_close(h);
        return err;
    }
    return 0;
}

int url_fclose(ByteIOContext *s)
{
    URLContext *h = s->opaque;
    
    av_free(s->buffer);
    memset(s, 0, sizeof(ByteIOContext));
    return url_close(h);
}

URLContext *url_fileno(ByteIOContext *s)
{
    return s->opaque;
}

#ifdef CONFIG_ENCODERS
/* XXX: currently size is limited */
int url_fprintf(ByteIOContext *s, const char *fmt, ...)
{
    va_list ap;
    char buf[4096];
    int ret;

    va_start(ap, fmt);
    ret = vsnprintf(buf, sizeof(buf), fmt, ap);
    va_end(ap);
    put_buffer(s, buf, strlen(buf));
    return ret;
}
#endif //CONFIG_ENCODERS

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

    c = url_fgetc(s);
    if (c == EOF)
        return NULL;
    q = buf;
    for(;;) {
        if (c == EOF || c == '\n')
            break;
        if ((q - buf) < buf_size - 1)
            *q++ = c;
        c = url_fgetc(s);
    }
    if (buf_size > 0)
        *q = '\0';
    return buf;
}

/* 
 * Return the maximum packet size associated to packetized buffered file
 * handle. If the file is not packetized (stream like http or file on
 * disk), then 0 is returned.
 * 
 * @param h buffered file handle
 * @return maximum packet size in bytes
 */
int url_fget_max_packet_size(ByteIOContext *s)
{
    return s->max_packet_size;
}

#ifdef CONFIG_ENCODERS
/* buffer handling */
int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags)
{
    return init_put_byte(s, buf, buf_size, 
                         (flags & URL_WRONLY || flags & URL_RDWR),
                         NULL, NULL, NULL, NULL);
}

/* return the written or read size */
int url_close_buf(ByteIOContext *s)
{
    put_flush_packet(s);
    return s->buf_ptr - s->buffer;
}

/* output in a dynamic buffer */

typedef struct DynBuffer {
    int pos, size, allocated_size;
    uint8_t *buffer;
    int io_buffer_size;
    uint8_t io_buffer[1];
} DynBuffer;

static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
{
    DynBuffer *d = opaque;
    int new_size, new_allocated_size;
    
    /* reallocate buffer if needed */
    new_size = d->pos + buf_size;
    new_allocated_size = d->allocated_size;
    if(new_size < d->pos || new_size > INT_MAX/2)
        return -1;
    while (new_size > new_allocated_size) {
        if (!new_allocated_size)
            new_allocated_size = new_size;
        else
            new_allocated_size += new_allocated_size / 2 + 1;    
    }
    
    if (new_allocated_size > d->allocated_size) {
        d->buffer = av_realloc(d->buffer, new_allocated_size);
        if(d->buffer == NULL)
             return -1234;
        d->allocated_size = new_allocated_size;
    }
    memcpy(d->buffer + d->pos, buf, buf_size);
    d->pos = new_size;
    if (d->pos > d->size)
        d->size = d->pos;
    return buf_size;
}

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

    /* packetized write: output the header */
    buf1[0] = (buf_size >> 24);
    buf1[1] = (buf_size >> 16);
    buf1[2] = (buf_size >> 8);
    buf1[3] = (buf_size);
    ret= dyn_buf_write(opaque, buf1, 4);
    if(ret < 0)
        return ret;

    /* then the data */
    return dyn_buf_write(opaque, buf, buf_size);
}

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

    if (whence == SEEK_CUR)
        offset += d->pos;
    else if (whence == SEEK_END)
        offset += d->size;
    if (offset < 0 || offset > 0x7fffffffLL)
        return -1;
    d->pos = offset;
    return 0;
}

static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
{
    DynBuffer *d;
    int io_buffer_size, ret;
    
    if (max_packet_size) 
        io_buffer_size = max_packet_size;
    else
        io_buffer_size = 1024;
        
    if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
        return -1;
    d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
    if (!d)
        return -1;
    d->io_buffer_size = io_buffer_size;
    d->buffer = NULL;
    d->pos = 0;
    d->size = 0;
    d->allocated_size = 0;
    ret = init_put_byte(s, d->io_buffer, io_buffer_size, 
                        1, d, NULL, 
                        max_packet_size ? dyn_packet_buf_write : dyn_buf_write, 
                        max_packet_size ? NULL : dyn_buf_seek);
    if (ret == 0) {
        s->max_packet_size = max_packet_size;
    }
    return ret;
}

/*
 * Open a write only memory stream.
 * 
 * @param s new IO context
 * @return zero if no error.
 */
int url_open_dyn_buf(ByteIOContext *s)
{
    return url_open_dyn_buf_internal(s, 0);
}

/*
 * Open a write only packetized memory stream with a maximum packet
 * size of 'max_packet_size'.  The stream is stored in a memory buffer
 * with a big endian 4 byte header giving the packet size in bytes.
 * 
 * @param s new IO context
 * @param max_packet_size maximum packet size (must be > 0) 
 * @return zero if no error.
 */
int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
{
    if (max_packet_size <= 0)
        return -1;
    return url_open_dyn_buf_internal(s, max_packet_size);
}

/* 
 * Return the written size and a pointer to the buffer. The buffer
 *  must be freed with av_free(). 
 * @param s IO context
 * @param pointer to a byte buffer
 * @return the length of the byte buffer
 */
int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
{
    DynBuffer *d = s->opaque;
    int size;

    put_flush_packet(s);

    *pbuffer = d->buffer;
    size = d->size;
    av_free(d);
    return size;
}
#endif //CONFIG_ENCODERS