2 * Buffered I/O for ffmpeg system
3 * Copyright (c) 2000,2001 Fabrice Bellard
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.
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.
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
23 #define IO_BUFFER_SIZE 32768
25 int init_put_byte(ByteIOContext *s,
26 unsigned char *buffer,
30 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
31 void (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
32 int (*seek)(void *opaque, offset_t offset, int whence))
35 s->buffer_size = buffer_size;
37 s->write_flag = write_flag;
41 s->buf_end = buffer + buffer_size;
43 s->write_packet = write_packet;
44 s->read_packet = read_packet;
50 s->max_packet_size = 0;
51 s->update_checksum= NULL;
56 #ifdef CONFIG_ENCODERS
57 static void flush_buffer(ByteIOContext *s)
59 if (s->buf_ptr > s->buffer) {
61 s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
62 if(s->update_checksum){
63 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
64 s->checksum_ptr= s->buffer;
66 s->pos += s->buf_ptr - s->buffer;
68 s->buf_ptr = s->buffer;
71 void put_byte(ByteIOContext *s, int b)
74 if (s->buf_ptr >= s->buf_end)
78 void put_buffer(ByteIOContext *s, const unsigned char *buf, int size)
83 len = (s->buf_end - s->buf_ptr);
86 memcpy(s->buf_ptr, buf, len);
89 if (s->buf_ptr >= s->buf_end)
97 void put_flush_packet(ByteIOContext *s)
102 #endif //CONFIG_ENCODERS
104 offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence)
108 if (whence != SEEK_CUR && whence != SEEK_SET)
111 #ifdef CONFIG_ENCODERS
113 if (whence == SEEK_CUR) {
114 offset1 = s->pos + (s->buf_ptr - s->buffer);
119 offset1 = offset - s->pos;
120 if (!s->must_flush &&
121 offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) {
122 /* can do the seek inside the buffer */
123 s->buf_ptr = s->buffer + offset1;
129 s->buf_ptr = s->buffer;
130 s->seek(s->opaque, offset, SEEK_SET);
134 #endif //CONFIG_ENCODERS
136 if (whence == SEEK_CUR) {
137 offset1 = s->pos - (s->buf_end - s->buffer) + (s->buf_ptr - s->buffer);
142 offset1 = offset - (s->pos - (s->buf_end - s->buffer));
143 if (offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
144 /* can do the seek inside the buffer */
145 s->buf_ptr = s->buffer + offset1;
149 s->buf_ptr = s->buffer;
150 s->buf_end = s->buffer;
151 if (s->seek(s->opaque, offset, SEEK_SET) == (offset_t)-EPIPE)
160 void url_fskip(ByteIOContext *s, offset_t offset)
162 url_fseek(s, offset, SEEK_CUR);
165 offset_t url_ftell(ByteIOContext *s)
167 return url_fseek(s, 0, SEEK_CUR);
170 int url_feof(ByteIOContext *s)
172 return s->eof_reached;
175 #ifdef CONFIG_ENCODERS
176 void put_le32(ByteIOContext *s, unsigned int val)
179 put_byte(s, val >> 8);
180 put_byte(s, val >> 16);
181 put_byte(s, val >> 24);
184 void put_be32(ByteIOContext *s, unsigned int val)
186 put_byte(s, val >> 24);
187 put_byte(s, val >> 16);
188 put_byte(s, val >> 8);
192 /* IEEE format is assumed */
193 void put_be64_double(ByteIOContext *s, double val)
203 void put_strz(ByteIOContext *s, const char *str)
206 put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
211 void put_le64(ByteIOContext *s, uint64_t val)
213 put_le32(s, (uint32_t)(val & 0xffffffff));
214 put_le32(s, (uint32_t)(val >> 32));
217 void put_be64(ByteIOContext *s, uint64_t val)
219 put_be32(s, (uint32_t)(val >> 32));
220 put_be32(s, (uint32_t)(val & 0xffffffff));
223 void put_le16(ByteIOContext *s, unsigned int val)
226 put_byte(s, val >> 8);
229 void put_be16(ByteIOContext *s, unsigned int val)
231 put_byte(s, val >> 8);
235 void put_tag(ByteIOContext *s, const char *tag)
241 #endif //CONFIG_ENCODERS
245 static void fill_buffer(ByteIOContext *s)
249 /* no need to do anything if EOF already reached */
253 if(s->update_checksum){
254 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
255 s->checksum_ptr= s->buffer;
258 len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
260 /* do not modify buffer if EOF reached so that a seek back can
261 be done without rereading data */
265 s->buf_ptr = s->buffer;
266 s->buf_end = s->buffer + len;
270 unsigned long get_checksum(ByteIOContext *s){
271 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
272 s->update_checksum= NULL;
276 void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){
277 s->update_checksum= update_checksum;
278 if(s->update_checksum){
279 s->checksum= s->update_checksum(checksum, NULL, 0);
280 s->checksum_ptr= s->buf_ptr;
284 /* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
286 /* XXX: put an inline version */
287 int get_byte(ByteIOContext *s)
289 if (s->buf_ptr < s->buf_end) {
290 return *s->buf_ptr++;
293 if (s->buf_ptr < s->buf_end)
294 return *s->buf_ptr++;
300 /* NOTE: return URL_EOF (-1) if EOF */
301 int url_fgetc(ByteIOContext *s)
303 if (s->buf_ptr < s->buf_end) {
304 return *s->buf_ptr++;
307 if (s->buf_ptr < s->buf_end)
308 return *s->buf_ptr++;
314 int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
320 len = s->buf_end - s->buf_ptr;
325 len = s->buf_end - s->buf_ptr;
329 memcpy(buf, s->buf_ptr, len);
338 int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
342 len = s->buf_end - s->buf_ptr;
345 len = s->buf_end - s->buf_ptr;
349 memcpy(buf, s->buf_ptr, len);
354 unsigned int get_le16(ByteIOContext *s)
358 val |= get_byte(s) << 8;
362 unsigned int get_le32(ByteIOContext *s)
366 val |= get_byte(s) << 8;
367 val |= get_byte(s) << 16;
368 val |= get_byte(s) << 24;
372 uint64_t get_le64(ByteIOContext *s)
375 val = (uint64_t)get_le32(s);
376 val |= (uint64_t)get_le32(s) << 32;
380 unsigned int get_be16(ByteIOContext *s)
383 val = get_byte(s) << 8;
388 unsigned int get_be32(ByteIOContext *s)
391 val = get_byte(s) << 24;
392 val |= get_byte(s) << 16;
393 val |= get_byte(s) << 8;
398 double get_be64_double(ByteIOContext *s)
409 char *get_strz(ByteIOContext *s, char *buf, int maxlen)
414 while ((c = get_byte(s))) {
419 buf[i] = 0; /* Ensure null terminated, but may be truncated */
424 uint64_t get_be64(ByteIOContext *s)
427 val = (uint64_t)get_be32(s) << 32;
428 val |= (uint64_t)get_be32(s);
432 /* link with avio functions */
434 #ifdef CONFIG_ENCODERS
435 static void url_write_packet(void *opaque, uint8_t *buf, int buf_size)
437 URLContext *h = opaque;
438 url_write(h, buf, buf_size);
441 #define url_write_packet NULL
442 #endif //CONFIG_ENCODERS
444 static int url_read_packet(void *opaque, uint8_t *buf, int buf_size)
446 URLContext *h = opaque;
447 return url_read(h, buf, buf_size);
450 static int url_seek_packet(void *opaque, int64_t offset, int whence)
452 URLContext *h = opaque;
453 return url_seek(h, offset, whence);
457 int url_fdopen(ByteIOContext *s, URLContext *h)
460 int buffer_size, max_packet_size;
463 max_packet_size = url_get_max_packet_size(h);
464 if (max_packet_size) {
465 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
467 buffer_size = IO_BUFFER_SIZE;
469 buffer = av_malloc(buffer_size);
473 if (init_put_byte(s, buffer, buffer_size,
474 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
475 url_read_packet, url_write_packet, url_seek_packet) < 0) {
479 s->is_streamed = h->is_streamed;
480 s->max_packet_size = max_packet_size;
484 /* XXX: must be called before any I/O */
485 int url_setbufsize(ByteIOContext *s, int buf_size)
488 buffer = av_malloc(buf_size);
494 s->buffer_size = buf_size;
499 s->buf_end = buffer + buf_size;
503 /* NOTE: when opened as read/write, the buffers are only used for
505 int url_fopen(ByteIOContext *s, const char *filename, int flags)
510 err = url_open(&h, filename, flags);
513 err = url_fdopen(s, h);
521 int url_fclose(ByteIOContext *s)
523 URLContext *h = s->opaque;
526 memset(s, 0, sizeof(ByteIOContext));
530 URLContext *url_fileno(ByteIOContext *s)
535 #ifdef CONFIG_ENCODERS
536 /* XXX: currently size is limited */
537 int url_fprintf(ByteIOContext *s, const char *fmt, ...)
544 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
546 put_buffer(s, buf, strlen(buf));
549 #endif //CONFIG_ENCODERS
551 /* note: unlike fgets, the EOL character is not returned and a whole
552 line is parsed. return NULL if first char read was EOF */
553 char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
563 if (c == EOF || c == '\n')
565 if ((q - buf) < buf_size - 1)
575 * Return the maximum packet size associated to packetized buffered file
576 * handle. If the file is not packetized (stream like http or file on
577 * disk), then 0 is returned.
579 * @param h buffered file handle
580 * @return maximum packet size in bytes
582 int url_fget_max_packet_size(ByteIOContext *s)
584 return s->max_packet_size;
587 #ifdef CONFIG_ENCODERS
588 /* buffer handling */
589 int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags)
591 return init_put_byte(s, buf, buf_size,
592 (flags & URL_WRONLY || flags & URL_RDWR),
593 NULL, NULL, NULL, NULL);
596 /* return the written or read size */
597 int url_close_buf(ByteIOContext *s)
600 return s->buf_ptr - s->buffer;
603 /* output in a dynamic buffer */
605 typedef struct DynBuffer {
606 int pos, size, allocated_size;
609 uint8_t io_buffer[1];
612 static void dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
614 DynBuffer *d = opaque;
615 int new_size, new_allocated_size;
617 /* reallocate buffer if needed */
618 new_size = d->pos + buf_size;
619 new_allocated_size = d->allocated_size;
620 while (new_size > new_allocated_size) {
621 if (!new_allocated_size)
622 new_allocated_size = new_size;
624 new_allocated_size = (new_allocated_size * 3) / 2 + 1;
627 if (new_allocated_size > d->allocated_size) {
628 d->buffer = av_realloc(d->buffer, new_allocated_size);
629 if(d->buffer == NULL)
631 d->allocated_size = new_allocated_size;
633 memcpy(d->buffer + d->pos, buf, buf_size);
635 if (d->pos > d->size)
639 static void dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
641 unsigned char buf1[4];
643 /* packetized write: output the header */
644 buf1[0] = (buf_size >> 24);
645 buf1[1] = (buf_size >> 16);
646 buf1[2] = (buf_size >> 8);
647 buf1[3] = (buf_size);
648 dyn_buf_write(opaque, buf1, 4);
651 dyn_buf_write(opaque, buf, buf_size);
654 static int dyn_buf_seek(void *opaque, offset_t offset, int whence)
656 DynBuffer *d = opaque;
658 if (whence == SEEK_CUR)
660 else if (whence == SEEK_END)
662 if (offset < 0 || offset > 0x7fffffffLL)
668 static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
671 int io_buffer_size, ret;
674 io_buffer_size = max_packet_size;
676 io_buffer_size = 1024;
678 d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
681 d->io_buffer_size = io_buffer_size;
685 d->allocated_size = 0;
686 ret = init_put_byte(s, d->io_buffer, io_buffer_size,
688 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
689 max_packet_size ? NULL : dyn_buf_seek);
691 s->max_packet_size = max_packet_size;
697 * Open a write only memory stream.
699 * @param s new IO context
700 * @return zero if no error.
702 int url_open_dyn_buf(ByteIOContext *s)
704 return url_open_dyn_buf_internal(s, 0);
708 * Open a write only packetized memory stream with a maximum packet
709 * size of 'max_packet_size'. The stream is stored in a memory buffer
710 * with a big endian 4 byte header giving the packet size in bytes.
712 * @param s new IO context
713 * @param max_packet_size maximum packet size (must be > 0)
714 * @return zero if no error.
716 int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
718 if (max_packet_size <= 0)
720 return url_open_dyn_buf_internal(s, max_packet_size);
724 * Return the written size and a pointer to the buffer. The buffer
725 * must be freed with av_free().
726 * @param s IO context
727 * @param pointer to a byte buffer
728 * @return the length of the byte buffer
730 int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
732 DynBuffer *d = s->opaque;
737 *pbuffer = d->buffer;
742 #endif //CONFIG_ENCODERS