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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 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 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
32 offset_t (*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;
51 s->max_packet_size = 0;
52 s->update_checksum= NULL;
56 static void flush_buffer(ByteIOContext *s)
58 if (s->buf_ptr > s->buffer) {
59 if (s->write_packet && !s->error){
60 int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
65 if(s->update_checksum){
66 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
67 s->checksum_ptr= s->buffer;
69 s->pos += s->buf_ptr - s->buffer;
71 s->buf_ptr = s->buffer;
74 void put_byte(ByteIOContext *s, int b)
77 if (s->buf_ptr >= s->buf_end)
81 void put_buffer(ByteIOContext *s, const unsigned char *buf, int size)
86 len = (s->buf_end - s->buf_ptr);
89 memcpy(s->buf_ptr, buf, len);
92 if (s->buf_ptr >= s->buf_end)
100 void put_flush_packet(ByteIOContext *s)
106 offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence)
109 offset_t pos= s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
111 if (whence != SEEK_CUR && whence != SEEK_SET)
114 if (whence == SEEK_CUR) {
115 offset1 = pos + (s->buf_ptr - s->buffer);
120 offset1 = offset - pos;
121 if (!s->must_flush &&
122 offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) {
123 /* can do the seek inside the buffer */
124 s->buf_ptr = s->buffer + offset1;
134 #endif //CONFIG_MUXERS
136 s->buf_end = s->buffer;
138 s->buf_ptr = s->buffer;
139 if (s->seek(s->opaque, offset, SEEK_SET) == (offset_t)-EPIPE)
147 void url_fskip(ByteIOContext *s, offset_t offset)
149 url_fseek(s, offset, SEEK_CUR);
152 offset_t url_ftell(ByteIOContext *s)
154 return url_fseek(s, 0, SEEK_CUR);
157 offset_t url_fsize(ByteIOContext *s)
163 size = s->seek(s->opaque, -1, SEEK_END) + 1;
164 s->seek(s->opaque, s->pos, SEEK_SET);
168 int url_feof(ByteIOContext *s)
170 return s->eof_reached;
173 int url_ferror(ByteIOContext *s)
178 #if defined(CONFIG_MUXERS) || defined(CONFIG_PROTOCOLS)
179 void put_le32(ByteIOContext *s, unsigned int val)
182 put_byte(s, val >> 8);
183 put_byte(s, val >> 16);
184 put_byte(s, val >> 24);
187 void put_be32(ByteIOContext *s, unsigned int val)
189 put_byte(s, val >> 24);
190 put_byte(s, val >> 16);
191 put_byte(s, val >> 8);
195 void put_strz(ByteIOContext *s, const char *str)
198 put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
203 void put_le64(ByteIOContext *s, uint64_t val)
205 put_le32(s, (uint32_t)(val & 0xffffffff));
206 put_le32(s, (uint32_t)(val >> 32));
209 void put_be64(ByteIOContext *s, uint64_t val)
211 put_be32(s, (uint32_t)(val >> 32));
212 put_be32(s, (uint32_t)(val & 0xffffffff));
215 void put_le16(ByteIOContext *s, unsigned int val)
218 put_byte(s, val >> 8);
221 void put_be16(ByteIOContext *s, unsigned int val)
223 put_byte(s, val >> 8);
227 void put_le24(ByteIOContext *s, unsigned int val)
229 put_le16(s, val & 0xffff);
230 put_byte(s, val >> 16);
233 void put_be24(ByteIOContext *s, unsigned int val)
235 put_be16(s, val >> 8);
239 void put_tag(ByteIOContext *s, const char *tag)
245 #endif //CONFIG_MUXERS || CONFIG_PROTOCOLS
249 static void fill_buffer(ByteIOContext *s)
253 /* no need to do anything if EOF already reached */
257 if(s->update_checksum){
258 if(s->buf_end > s->checksum_ptr)
259 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
260 s->checksum_ptr= s->buffer;
263 len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
265 /* do not modify buffer if EOF reached so that a seek back can
266 be done without rereading data */
272 s->buf_ptr = s->buffer;
273 s->buf_end = s->buffer + len;
277 unsigned long get_checksum(ByteIOContext *s){
278 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
279 s->update_checksum= NULL;
283 void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){
284 s->update_checksum= update_checksum;
285 if(s->update_checksum){
286 s->checksum= checksum;
287 s->checksum_ptr= s->buf_ptr;
291 /* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
293 /* XXX: put an inline version */
294 int get_byte(ByteIOContext *s)
296 if (s->buf_ptr < s->buf_end) {
297 return *s->buf_ptr++;
300 if (s->buf_ptr < s->buf_end)
301 return *s->buf_ptr++;
307 /* NOTE: return URL_EOF (-1) if EOF */
308 int url_fgetc(ByteIOContext *s)
310 if (s->buf_ptr < s->buf_end) {
311 return *s->buf_ptr++;
314 if (s->buf_ptr < s->buf_end)
315 return *s->buf_ptr++;
321 int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
327 len = s->buf_end - s->buf_ptr;
331 if(size > s->buffer_size && !s->update_checksum){
332 len = s->read_packet(s->opaque, buf, size);
334 /* do not modify buffer if EOF reached so that a seek back can
335 be done without rereading data */
344 s->buf_ptr = s->buffer;
345 s->buf_end = s->buffer/* + len*/;
349 len = s->buf_end - s->buf_ptr;
354 memcpy(buf, s->buf_ptr, len);
363 int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
370 len = s->buf_end - s->buf_ptr;
373 len = s->buf_end - s->buf_ptr;
377 memcpy(buf, s->buf_ptr, len);
382 unsigned int get_le16(ByteIOContext *s)
386 val |= get_byte(s) << 8;
390 unsigned int get_le24(ByteIOContext *s)
394 val |= get_byte(s) << 16;
398 unsigned int get_le32(ByteIOContext *s)
402 val |= get_le16(s) << 16;
406 uint64_t get_le64(ByteIOContext *s)
409 val = (uint64_t)get_le32(s);
410 val |= (uint64_t)get_le32(s) << 32;
414 unsigned int get_be16(ByteIOContext *s)
417 val = get_byte(s) << 8;
422 unsigned int get_be24(ByteIOContext *s)
425 val = get_be16(s) << 8;
429 unsigned int get_be32(ByteIOContext *s)
432 val = get_be16(s) << 16;
437 char *get_strz(ByteIOContext *s, char *buf, int maxlen)
442 while ((c = get_byte(s))) {
447 buf[i] = 0; /* Ensure null terminated, but may be truncated */
452 uint64_t get_be64(ByteIOContext *s)
455 val = (uint64_t)get_be32(s) << 32;
456 val |= (uint64_t)get_be32(s);
460 /* link with avio functions */
463 static int url_write_packet(void *opaque, uint8_t *buf, int buf_size)
465 URLContext *h = opaque;
466 return url_write(h, buf, buf_size);
469 #define url_write_packet NULL
470 #endif //CONFIG_MUXERS
472 static int url_read_packet(void *opaque, uint8_t *buf, int buf_size)
474 URLContext *h = opaque;
475 return url_read(h, buf, buf_size);
478 static offset_t url_seek_packet(void *opaque, offset_t offset, int whence)
480 URLContext *h = opaque;
481 return url_seek(h, offset, whence);
485 int url_fdopen(ByteIOContext *s, URLContext *h)
488 int buffer_size, max_packet_size;
491 max_packet_size = url_get_max_packet_size(h);
492 if (max_packet_size) {
493 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
495 buffer_size = IO_BUFFER_SIZE;
497 buffer = av_malloc(buffer_size);
501 if (init_put_byte(s, buffer, buffer_size,
502 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
503 url_read_packet, url_write_packet, url_seek_packet) < 0) {
507 s->is_streamed = h->is_streamed;
508 s->max_packet_size = max_packet_size;
512 /* XXX: must be called before any I/O */
513 int url_setbufsize(ByteIOContext *s, int buf_size)
516 buffer = av_malloc(buf_size);
522 s->buffer_size = buf_size;
527 s->buf_end = buffer + buf_size;
531 /* NOTE: when opened as read/write, the buffers are only used for
533 int url_fopen(ByteIOContext *s, const char *filename, int flags)
538 err = url_open(&h, filename, flags);
541 err = url_fdopen(s, h);
549 int url_fclose(ByteIOContext *s)
551 URLContext *h = s->opaque;
554 memset(s, 0, sizeof(ByteIOContext));
558 URLContext *url_fileno(ByteIOContext *s)
564 /* XXX: currently size is limited */
565 int url_fprintf(ByteIOContext *s, const char *fmt, ...)
572 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
574 put_buffer(s, buf, strlen(buf));
577 #endif //CONFIG_MUXERS
579 /* note: unlike fgets, the EOL character is not returned and a whole
580 line is parsed. return NULL if first char read was EOF */
581 char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
591 if (c == EOF || c == '\n')
593 if ((q - buf) < buf_size - 1)
603 * Return the maximum packet size associated to packetized buffered file
604 * handle. If the file is not packetized (stream like http or file on
605 * disk), then 0 is returned.
607 * @param h buffered file handle
608 * @return maximum packet size in bytes
610 int url_fget_max_packet_size(ByteIOContext *s)
612 return s->max_packet_size;
616 /* buffer handling */
617 int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags)
619 return init_put_byte(s, buf, buf_size,
620 (flags & URL_WRONLY || flags & URL_RDWR),
621 NULL, NULL, NULL, NULL);
624 /* return the written or read size */
625 int url_close_buf(ByteIOContext *s)
628 return s->buf_ptr - s->buffer;
631 /* output in a dynamic buffer */
633 typedef struct DynBuffer {
634 int pos, size, allocated_size;
637 uint8_t io_buffer[1];
640 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
642 DynBuffer *d = opaque;
643 int new_size, new_allocated_size;
645 /* reallocate buffer if needed */
646 new_size = d->pos + buf_size;
647 new_allocated_size = d->allocated_size;
648 if(new_size < d->pos || new_size > INT_MAX/2)
650 while (new_size > new_allocated_size) {
651 if (!new_allocated_size)
652 new_allocated_size = new_size;
654 new_allocated_size += new_allocated_size / 2 + 1;
657 if (new_allocated_size > d->allocated_size) {
658 d->buffer = av_realloc(d->buffer, new_allocated_size);
659 if(d->buffer == NULL)
661 d->allocated_size = new_allocated_size;
663 memcpy(d->buffer + d->pos, buf, buf_size);
665 if (d->pos > d->size)
670 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
672 unsigned char buf1[4];
675 /* packetized write: output the header */
676 buf1[0] = (buf_size >> 24);
677 buf1[1] = (buf_size >> 16);
678 buf1[2] = (buf_size >> 8);
679 buf1[3] = (buf_size);
680 ret= dyn_buf_write(opaque, buf1, 4);
685 return dyn_buf_write(opaque, buf, buf_size);
688 static offset_t dyn_buf_seek(void *opaque, offset_t offset, int whence)
690 DynBuffer *d = opaque;
692 if (whence == SEEK_CUR)
694 else if (whence == SEEK_END)
696 if (offset < 0 || offset > 0x7fffffffLL)
702 static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
705 int io_buffer_size, ret;
708 io_buffer_size = max_packet_size;
710 io_buffer_size = 1024;
712 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
714 d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
717 d->io_buffer_size = io_buffer_size;
721 d->allocated_size = 0;
722 ret = init_put_byte(s, d->io_buffer, io_buffer_size,
724 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
725 max_packet_size ? NULL : dyn_buf_seek);
727 s->max_packet_size = max_packet_size;
733 * Open a write only memory stream.
735 * @param s new IO context
736 * @return zero if no error.
738 int url_open_dyn_buf(ByteIOContext *s)
740 return url_open_dyn_buf_internal(s, 0);
744 * Open a write only packetized memory stream with a maximum packet
745 * size of 'max_packet_size'. The stream is stored in a memory buffer
746 * with a big endian 4 byte header giving the packet size in bytes.
748 * @param s new IO context
749 * @param max_packet_size maximum packet size (must be > 0)
750 * @return zero if no error.
752 int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
754 if (max_packet_size <= 0)
756 return url_open_dyn_buf_internal(s, max_packet_size);
760 * Return the written size and a pointer to the buffer. The buffer
761 * must be freed with av_free().
762 * @param s IO context
763 * @param pointer to a byte buffer
764 * @return the length of the byte buffer
766 int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
768 DynBuffer *d = s->opaque;
773 *pbuffer = d->buffer;
778 #endif //CONFIG_MUXERS