added dynamic buffer support - added url_fprintf() and url_fgetc()
[libav.git] / libav / aviobuf.c
CommitLineData
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1/*
2 * Buffered I/O for ffmpeg system
19720f15 3 * Copyright (c) 2000,2001 Fabrice Bellard
de6d9b64 4 *
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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.
de6d9b64 9 *
19720f15 10 * This library is distributed in the hope that it will be useful,
de6d9b64 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
de6d9b64 14 *
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15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
de6d9b64 18 */
de6d9b64 19#include "avformat.h"
abba3dd1 20#include <stdarg.h>
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21
22#define IO_BUFFER_SIZE 32768
23
24int init_put_byte(ByteIOContext *s,
25 unsigned char *buffer,
26 int buffer_size,
27 int write_flag,
28 void *opaque,
29 int (*read_packet)(void *opaque, UINT8 *buf, int buf_size),
30 void (*write_packet)(void *opaque, UINT8 *buf, int buf_size),
31 int (*seek)(void *opaque, offset_t offset, int whence))
32{
33 s->buffer = buffer;
34 s->buffer_size = buffer_size;
35 s->buf_ptr = buffer;
36 s->write_flag = write_flag;
37 if (!s->write_flag)
38 s->buf_end = buffer;
39 else
40 s->buf_end = buffer + buffer_size;
41 s->opaque = opaque;
42 s->write_packet = write_packet;
43 s->read_packet = read_packet;
44 s->seek = seek;
45 s->pos = 0;
46 s->must_flush = 0;
47 s->eof_reached = 0;
48 s->is_streamed = 0;
abba3dd1 49 s->max_packet_size = 0;
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50 return 0;
51}
52
53
54static void flush_buffer(ByteIOContext *s)
55{
56 if (s->buf_ptr > s->buffer) {
57 if (s->write_packet)
58 s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
59 s->pos += s->buf_ptr - s->buffer;
60 }
61 s->buf_ptr = s->buffer;
62}
63
64void put_byte(ByteIOContext *s, int b)
65{
66 *(s->buf_ptr)++ = b;
67 if (s->buf_ptr >= s->buf_end)
68 flush_buffer(s);
69}
70
71void put_buffer(ByteIOContext *s, unsigned char *buf, int size)
72{
73 int len;
74
75 while (size > 0) {
76 len = (s->buf_end - s->buf_ptr);
77 if (len > size)
78 len = size;
79 memcpy(s->buf_ptr, buf, len);
80 s->buf_ptr += len;
81
82 if (s->buf_ptr >= s->buf_end)
83 flush_buffer(s);
84
85 buf += len;
86 size -= len;
87 }
88}
89
90void put_flush_packet(ByteIOContext *s)
91{
92 flush_buffer(s);
93 s->must_flush = 0;
94}
95
96offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence)
97{
98 offset_t offset1;
99
100 if (whence != SEEK_CUR && whence != SEEK_SET)
101 return -EINVAL;
102
103 if (s->write_flag) {
104 if (whence == SEEK_CUR) {
4606ac8d 105 offset1 = s->pos + (s->buf_ptr - s->buffer);
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106 if (offset == 0)
107 return offset1;
108 offset += offset1;
109 }
110 offset1 = offset - s->pos;
111 if (!s->must_flush &&
112 offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) {
113 /* can do the seek inside the buffer */
114 s->buf_ptr = s->buffer + offset1;
115 } else {
116 if (!s->seek)
117 return -EPIPE;
118 flush_buffer(s);
119 s->must_flush = 1;
120 s->buf_ptr = s->buffer;
121 s->seek(s->opaque, offset, SEEK_SET);
122 s->pos = offset;
123 }
124 } else {
125 if (whence == SEEK_CUR) {
126 offset1 = s->pos - (s->buf_end - s->buffer) + (s->buf_ptr - s->buffer);
127 if (offset == 0)
128 return offset1;
129 offset += offset1;
130 }
131 offset1 = offset - (s->pos - (s->buf_end - s->buffer));
132 if (offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
133 /* can do the seek inside the buffer */
134 s->buf_ptr = s->buffer + offset1;
135 } else {
136 if (!s->seek)
137 return -EPIPE;
138 s->buf_ptr = s->buffer;
139 s->buf_end = s->buffer;
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140 s->seek(s->opaque, offset, SEEK_SET);
141 s->pos = offset;
142 }
abba3dd1 143 s->eof_reached = 0;
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144 }
145 return offset;
146}
147
148void url_fskip(ByteIOContext *s, offset_t offset)
149{
150 url_fseek(s, offset, SEEK_CUR);
151}
152
153offset_t url_ftell(ByteIOContext *s)
154{
155 return url_fseek(s, 0, SEEK_CUR);
156}
157
158int url_feof(ByteIOContext *s)
159{
160 return s->eof_reached;
161}
162
163void put_le32(ByteIOContext *s, unsigned int val)
164{
165 put_byte(s, val);
166 put_byte(s, val >> 8);
167 put_byte(s, val >> 16);
168 put_byte(s, val >> 24);
169}
170
171void put_be32(ByteIOContext *s, unsigned int val)
172{
173 put_byte(s, val >> 24);
174 put_byte(s, val >> 16);
175 put_byte(s, val >> 8);
176 put_byte(s, val);
177}
178
8be1c656 179void put_le64(ByteIOContext *s, UINT64 val)
de6d9b64 180{
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181 put_le32(s, (UINT32)(val & 0xffffffff));
182 put_le32(s, (UINT32)(val >> 32));
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183}
184
8be1c656 185void put_be64(ByteIOContext *s, UINT64 val)
de6d9b64 186{
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187 put_be32(s, (UINT32)(val >> 32));
188 put_be32(s, (UINT32)(val & 0xffffffff));
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189}
190
191void put_le16(ByteIOContext *s, unsigned int val)
192{
193 put_byte(s, val);
194 put_byte(s, val >> 8);
195}
196
197void put_be16(ByteIOContext *s, unsigned int val)
198{
199 put_byte(s, val >> 8);
200 put_byte(s, val);
201}
202
203void put_tag(ByteIOContext *s, char *tag)
204{
205 while (*tag) {
206 put_byte(s, *tag++);
207 }
208}
209
210/* Input stream */
211
212static void fill_buffer(ByteIOContext *s)
213{
214 int len;
215
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216 /* no need to do anything if EOF already reached */
217 if (s->eof_reached)
218 return;
de6d9b64 219 len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
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220 if (len <= 0) {
221 /* do not modify buffer if EOF reached so that a seek back can
222 be done without rereading data */
de6d9b64 223 s->eof_reached = 1;
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224 } else {
225 s->pos += len;
226 s->buf_ptr = s->buffer;
227 s->buf_end = s->buffer + len;
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228 }
229}
230
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231/* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
232 necessary */
233/* XXX: put an inline version */
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234int get_byte(ByteIOContext *s)
235{
236 if (s->buf_ptr < s->buf_end) {
237 return *s->buf_ptr++;
238 } else {
239 fill_buffer(s);
240 if (s->buf_ptr < s->buf_end)
241 return *s->buf_ptr++;
242 else
243 return 0;
244 }
245}
246
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247/* NOTE: return URL_EOF (-1) if EOF */
248int url_fgetc(ByteIOContext *s)
249{
250 if (s->buf_ptr < s->buf_end) {
251 return *s->buf_ptr++;
252 } else {
253 fill_buffer(s);
254 if (s->buf_ptr < s->buf_end)
255 return *s->buf_ptr++;
256 else
257 return URL_EOF;
258 }
259}
260
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261int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
262{
263 int len, size1;
264
265 size1 = size;
266 while (size > 0) {
267 len = s->buf_end - s->buf_ptr;
268 if (len > size)
269 len = size;
270 if (len == 0) {
271 fill_buffer(s);
272 len = s->buf_end - s->buf_ptr;
273 if (len == 0)
274 break;
275 } else {
276 memcpy(buf, s->buf_ptr, len);
277 buf += len;
278 s->buf_ptr += len;
279 size -= len;
280 }
281 }
282 return size1 - size;
283}
284
285unsigned int get_le16(ByteIOContext *s)
286{
287 unsigned int val;
288 val = get_byte(s);
289 val |= get_byte(s) << 8;
290 return val;
291}
292
293unsigned int get_le32(ByteIOContext *s)
294{
295 unsigned int val;
296 val = get_byte(s);
297 val |= get_byte(s) << 8;
298 val |= get_byte(s) << 16;
299 val |= get_byte(s) << 24;
300 return val;
301}
302
8be1c656 303UINT64 get_le64(ByteIOContext *s)
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304{
305 UINT64 val;
306 val = (UINT64)get_le32(s);
307 val |= (UINT64)get_le32(s) << 32;
308 return val;
309}
310
311unsigned int get_be16(ByteIOContext *s)
312{
313 unsigned int val;
314 val = get_byte(s) << 8;
315 val |= get_byte(s);
316 return val;
317}
318
319unsigned int get_be32(ByteIOContext *s)
320{
321 unsigned int val;
322 val = get_byte(s) << 24;
323 val |= get_byte(s) << 16;
324 val |= get_byte(s) << 8;
325 val |= get_byte(s);
326 return val;
327}
328
8be1c656 329UINT64 get_be64(ByteIOContext *s)
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330{
331 UINT64 val;
332 val = (UINT64)get_be32(s) << 32;
333 val |= (UINT64)get_be32(s);
334 return val;
335}
336
337/* link with avio functions */
338
339void url_write_packet(void *opaque, UINT8 *buf, int buf_size)
340{
341 URLContext *h = opaque;
342 url_write(h, buf, buf_size);
343}
344
345int url_read_packet(void *opaque, UINT8 *buf, int buf_size)
346{
347 URLContext *h = opaque;
348 return url_read(h, buf, buf_size);
349}
350
8be1c656 351int url_seek_packet(void *opaque, INT64 offset, int whence)
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352{
353 URLContext *h = opaque;
354 url_seek(h, offset, whence);
355 return 0;
356}
357
358int url_fdopen(ByteIOContext *s, URLContext *h)
359{
360 UINT8 *buffer;
abba3dd1 361 int buffer_size, max_packet_size;
de6d9b64 362
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363
364 max_packet_size = url_get_max_packet_size(h);
365 if (max_packet_size) {
366 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
367 } else {
368 buffer_size = IO_BUFFER_SIZE;
369 }
1ea4f593 370 buffer = av_malloc(buffer_size);
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371 if (!buffer)
372 return -ENOMEM;
373
374 if (init_put_byte(s, buffer, buffer_size,
375 (h->flags & URL_WRONLY) != 0, h,
376 url_read_packet, url_write_packet, url_seek_packet) < 0) {
1ea4f593 377 av_free(buffer);
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378 return -EIO;
379 }
380 s->is_streamed = h->is_streamed;
abba3dd1 381 s->max_packet_size = max_packet_size;
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382 return 0;
383}
384
385/* XXX: must be called before any I/O */
386int url_setbufsize(ByteIOContext *s, int buf_size)
387{
388 UINT8 *buffer;
1ea4f593 389 buffer = av_malloc(buf_size);
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390 if (!buffer)
391 return -ENOMEM;
392
1ea4f593 393 av_free(s->buffer);
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394 s->buffer = buffer;
395 s->buffer_size = buf_size;
396 s->buf_ptr = buffer;
397 if (!s->write_flag)
398 s->buf_end = buffer;
399 else
400 s->buf_end = buffer + buf_size;
401 return 0;
402}
403
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404/* NOTE: when opened as read/write, the buffers are only used for
405 reading */
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406int url_fopen(ByteIOContext *s, const char *filename, int flags)
407{
408 URLContext *h;
409 int err;
410
411 err = url_open(&h, filename, flags);
412 if (err < 0)
413 return err;
414 err = url_fdopen(s, h);
415 if (err < 0) {
416 url_close(h);
417 return err;
418 }
419 return 0;
420}
421
422int url_fclose(ByteIOContext *s)
423{
424 URLContext *h = s->opaque;
425
1ea4f593 426 av_free(s->buffer);
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427 memset(s, 0, sizeof(ByteIOContext));
428 return url_close(h);
429}
430
431URLContext *url_fileno(ByteIOContext *s)
432{
433 return s->opaque;
434}
435
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436/* XXX: currently size is limited */
437int url_fprintf(ByteIOContext *s, const char *fmt, ...)
438{
439 va_list ap;
440 char buf[4096];
441 int ret;
442
443 va_start(ap, fmt);
444 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
445 va_end(ap);
446 put_buffer(s, buf, strlen(buf));
447 return ret;
448}
449
450/* note: unlike fgets, the EOL character is not returned and a whole
451 line is parsed. return NULL if first char read was EOF */
452char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
453{
454 int c;
455 char *q;
456
457 c = url_fgetc(s);
458 if (c == EOF)
459 return NULL;
460 q = buf;
461 for(;;) {
462 if (c == EOF || c == '\n')
463 break;
464 if ((q - buf) < buf_size - 1)
465 *q++ = c;
466 c = url_fgetc(s);
467 }
468 if (buf_size > 0)
469 *q = '\0';
470 return buf;
471}
472
473/*
474 * Return the maximum packet size associated to packetized buffered file
475 * handle. If the file is not packetized (stream like http or file on
476 * disk), then 0 is returned.
477 *
478 * @param h buffered file handle
479 * @return maximum packet size in bytes
480 */
481int url_fget_max_packet_size(ByteIOContext *s)
482{
483 return s->max_packet_size;
484}
485
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486/* buffer handling */
487int url_open_buf(ByteIOContext *s, UINT8 *buf, int buf_size, int flags)
488{
489 return init_put_byte(s, buf, buf_size,
490 (flags & URL_WRONLY) != 0, NULL, NULL, NULL, NULL);
491}
492
493/* return the written or read size */
494int url_close_buf(ByteIOContext *s)
495{
abba3dd1 496 put_flush_packet(s);
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497 return s->buf_ptr - s->buffer;
498}
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499
500/* output in a dynamic buffer */
501
502typedef struct DynBuffer {
503 int pos, size, allocated_size;
504 UINT8 *buffer;
505 int io_buffer_size;
506 UINT8 io_buffer[1];
507} DynBuffer;
508
509static void dyn_buf_write(void *opaque, UINT8 *buf, int buf_size)
510{
511 DynBuffer *d = opaque;
512 int new_size, new_allocated_size;
513 UINT8 *new_buffer;
514
515 /* reallocate buffer if needed */
516 new_size = d->pos + buf_size;
517 new_allocated_size = d->allocated_size;
518 while (new_size > new_allocated_size) {
519 if (!new_allocated_size)
520 new_allocated_size = new_size;
521 else
522 new_allocated_size = (new_allocated_size * 3) / 2;
523 }
524
525 if (new_allocated_size > d->allocated_size) {
526 new_buffer = av_malloc(new_allocated_size);
527 if (!new_buffer)
528 return;
529 memcpy(new_buffer, d->buffer, d->size);
530 av_free(d->buffer);
531 d->buffer = new_buffer;
532 d->allocated_size = new_allocated_size;
533 }
534 memcpy(d->buffer + d->pos, buf, buf_size);
535 d->pos = new_size;
536 if (d->pos > d->size)
537 d->size = d->pos;
538}
539
540static void dyn_packet_buf_write(void *opaque, UINT8 *buf, int buf_size)
541{
542 unsigned char buf1[4];
543
544 /* packetized write: output the header */
545 buf1[0] = (buf_size >> 24);
546 buf1[1] = (buf_size >> 16);
547 buf1[2] = (buf_size >> 8);
548 buf1[3] = (buf_size);
549 dyn_buf_write(opaque, buf1, 4);
550
551 /* then the data */
552 dyn_buf_write(opaque, buf, buf_size);
553}
554
555static int dyn_buf_seek(void *opaque, offset_t offset, int whence)
556{
557 DynBuffer *d = opaque;
558
559 if (whence == SEEK_CUR)
560 offset += d->pos;
561 else if (whence == SEEK_END)
562 offset += d->size;
563 if (offset < 0 || offset > 0x7fffffffLL)
564 return -1;
565 d->pos = offset;
566 return 0;
567}
568
569static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
570{
571 DynBuffer *d;
572 int io_buffer_size, ret;
573
574 if (max_packet_size)
575 io_buffer_size = max_packet_size;
576 else
577 io_buffer_size = 1024;
578
579 d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
580 if (!d)
581 return -1;
582 d->io_buffer_size = io_buffer_size;
583 d->buffer = NULL;
584 d->pos = 0;
585 d->size = 0;
586 d->allocated_size = 0;
587 ret = init_put_byte(s, d->io_buffer, io_buffer_size,
588 1, d, NULL,
589 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
590 max_packet_size ? NULL : dyn_buf_seek);
591 if (ret == 0) {
592 s->max_packet_size = max_packet_size;
593 }
594 return ret;
595}
596
597/*
598 * Open a write only memory stream.
599 *
600 * @param s new IO context
601 * @return zero if no error.
602 */
603int url_open_dyn_buf(ByteIOContext *s)
604{
605 return url_open_dyn_buf_internal(s, 0);
606}
607
608/*
609 * Open a write only packetized memory stream with a maximum packet
610 * size of 'max_packet_size'. The stream is stored in a memory buffer
611 * with a big endian 4 byte header giving the packet size in bytes.
612 *
613 * @param s new IO context
614 * @param max_packet_size maximum packet size (must be > 0)
615 * @return zero if no error.
616 */
617int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
618{
619 if (max_packet_size <= 0)
620 return -1;
621 return url_open_dyn_buf_internal(s, max_packet_size);
622}
623
624/*
625 * Return the written size and a pointer to the buffer. The buffer
626 * must be freed with av_free().
627 * @param s IO context
628 * @param pointer to a byte buffer
629 * @return the length of the byte buffer
630 */
631int url_close_dyn_buf(ByteIOContext *s, UINT8 **pbuffer)
632{
633 DynBuffer *d = s->opaque;
634 int size;
635
636 put_flush_packet(s);
637
638 *pbuffer = d->buffer;
639 size = d->size;
640 av_free(d);
641 return size;
642}