2 * Buffered I/O for ffmpeg system
3 * Copyright (c) 2000,2001 Fabrice Bellard
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 #define IO_BUFFER_SIZE 32768
27 static void fill_buffer(ByteIOContext *s);
29 int init_put_byte(ByteIOContext *s,
30 unsigned char *buffer,
34 int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
35 int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
36 offset_t (*seek)(void *opaque, offset_t offset, int whence))
39 s->buffer_size = buffer_size;
41 s->write_flag = write_flag;
45 s->buf_end = buffer + buffer_size;
47 s->write_packet = write_packet;
48 s->read_packet = read_packet;
55 s->max_packet_size = 0;
56 s->update_checksum= NULL;
57 if(!read_packet && !write_flag){
59 s->buf_end = s->buffer + buffer_size;
64 static void flush_buffer(ByteIOContext *s)
66 if (s->buf_ptr > s->buffer) {
67 if (s->write_packet && !s->error){
68 int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
73 if(s->update_checksum){
74 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
75 s->checksum_ptr= s->buffer;
77 s->pos += s->buf_ptr - s->buffer;
79 s->buf_ptr = s->buffer;
82 void put_byte(ByteIOContext *s, int b)
85 if (s->buf_ptr >= s->buf_end)
89 void put_buffer(ByteIOContext *s, const unsigned char *buf, int size)
94 len = (s->buf_end - s->buf_ptr);
97 memcpy(s->buf_ptr, buf, len);
100 if (s->buf_ptr >= s->buf_end)
108 void put_flush_packet(ByteIOContext *s)
114 offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence)
117 offset_t pos= s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
119 if (whence != SEEK_CUR && whence != SEEK_SET)
122 if (whence == SEEK_CUR) {
123 offset1 = pos + (s->buf_ptr - s->buffer);
128 offset1 = offset - pos;
129 if (!s->must_flush &&
130 offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) {
131 /* can do the seek inside the buffer */
132 s->buf_ptr = s->buffer + offset1;
133 } else if(s->is_streamed && !s->write_flag &&
134 offset1 >= 0 && offset1 < (s->buf_end - s->buffer) + (1<<16)){
135 while(s->pos < offset && !s->eof_reached)
137 s->buf_ptr = s->buf_end + offset - s->pos;
139 #if defined(CONFIG_MUXERS) || defined(CONFIG_NETWORK)
144 #endif /* defined(CONFIG_MUXERS) || defined(CONFIG_NETWORK) */
146 s->buf_end = s->buffer;
148 s->buf_ptr = s->buffer;
149 if (!s->seek || s->seek(s->opaque, offset, SEEK_SET) == (offset_t)-EPIPE)
157 void url_fskip(ByteIOContext *s, offset_t offset)
159 url_fseek(s, offset, SEEK_CUR);
162 offset_t url_ftell(ByteIOContext *s)
164 return url_fseek(s, 0, SEEK_CUR);
167 offset_t url_fsize(ByteIOContext *s)
173 size = s->seek(s->opaque, 0, AVSEEK_SIZE);
175 if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
178 s->seek(s->opaque, s->pos, SEEK_SET);
183 int url_feof(ByteIOContext *s)
185 return s->eof_reached;
188 int url_ferror(ByteIOContext *s)
193 void put_le32(ByteIOContext *s, unsigned int val)
196 put_byte(s, val >> 8);
197 put_byte(s, val >> 16);
198 put_byte(s, val >> 24);
201 void put_be32(ByteIOContext *s, unsigned int val)
203 put_byte(s, val >> 24);
204 put_byte(s, val >> 16);
205 put_byte(s, val >> 8);
209 void put_strz(ByteIOContext *s, const char *str)
212 put_buffer(s, (const unsigned char *) str, strlen(str) + 1);
217 void put_le64(ByteIOContext *s, uint64_t val)
219 put_le32(s, (uint32_t)(val & 0xffffffff));
220 put_le32(s, (uint32_t)(val >> 32));
223 void put_be64(ByteIOContext *s, uint64_t val)
225 put_be32(s, (uint32_t)(val >> 32));
226 put_be32(s, (uint32_t)(val & 0xffffffff));
229 void put_le16(ByteIOContext *s, unsigned int val)
232 put_byte(s, val >> 8);
235 void put_be16(ByteIOContext *s, unsigned int val)
237 put_byte(s, val >> 8);
241 void put_le24(ByteIOContext *s, unsigned int val)
243 put_le16(s, val & 0xffff);
244 put_byte(s, val >> 16);
247 void put_be24(ByteIOContext *s, unsigned int val)
249 put_be16(s, val >> 8);
253 void put_tag(ByteIOContext *s, const char *tag)
262 static void fill_buffer(ByteIOContext *s)
266 /* no need to do anything if EOF already reached */
270 if(s->update_checksum){
271 if(s->buf_end > s->checksum_ptr)
272 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
273 s->checksum_ptr= s->buffer;
276 len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
278 /* do not modify buffer if EOF reached so that a seek back can
279 be done without rereading data */
285 s->buf_ptr = s->buffer;
286 s->buf_end = s->buffer + len;
290 unsigned long get_checksum(ByteIOContext *s){
291 s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
292 s->update_checksum= NULL;
296 void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){
297 s->update_checksum= update_checksum;
298 if(s->update_checksum){
299 s->checksum= checksum;
300 s->checksum_ptr= s->buf_ptr;
304 /* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
306 /* XXX: put an inline version */
307 int get_byte(ByteIOContext *s)
309 if (s->buf_ptr < s->buf_end) {
310 return *s->buf_ptr++;
313 if (s->buf_ptr < s->buf_end)
314 return *s->buf_ptr++;
320 /* NOTE: return URL_EOF (-1) if EOF */
321 int url_fgetc(ByteIOContext *s)
323 if (s->buf_ptr < s->buf_end) {
324 return *s->buf_ptr++;
327 if (s->buf_ptr < s->buf_end)
328 return *s->buf_ptr++;
334 int get_buffer(ByteIOContext *s, unsigned char *buf, int size)
340 len = s->buf_end - s->buf_ptr;
344 if(size > s->buffer_size && !s->update_checksum){
345 len = s->read_packet(s->opaque, buf, size);
347 /* do not modify buffer if EOF reached so that a seek back can
348 be done without rereading data */
357 s->buf_ptr = s->buffer;
358 s->buf_end = s->buffer/* + len*/;
362 len = s->buf_end - s->buf_ptr;
367 memcpy(buf, s->buf_ptr, len);
376 int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size)
383 len = s->buf_end - s->buf_ptr;
386 len = s->buf_end - s->buf_ptr;
390 memcpy(buf, s->buf_ptr, len);
395 unsigned int get_le16(ByteIOContext *s)
399 val |= get_byte(s) << 8;
403 unsigned int get_le24(ByteIOContext *s)
407 val |= get_byte(s) << 16;
411 unsigned int get_le32(ByteIOContext *s)
415 val |= get_le16(s) << 16;
419 uint64_t get_le64(ByteIOContext *s)
422 val = (uint64_t)get_le32(s);
423 val |= (uint64_t)get_le32(s) << 32;
427 unsigned int get_be16(ByteIOContext *s)
430 val = get_byte(s) << 8;
435 unsigned int get_be24(ByteIOContext *s)
438 val = get_be16(s) << 8;
442 unsigned int get_be32(ByteIOContext *s)
445 val = get_be16(s) << 16;
450 char *get_strz(ByteIOContext *s, char *buf, int maxlen)
455 while ((c = get_byte(s))) {
460 buf[i] = 0; /* Ensure null terminated, but may be truncated */
465 uint64_t get_be64(ByteIOContext *s)
468 val = (uint64_t)get_be32(s) << 32;
469 val |= (uint64_t)get_be32(s);
473 /* link with avio functions */
476 static int url_write_packet(void *opaque, uint8_t *buf, int buf_size)
478 URLContext *h = opaque;
479 return url_write(h, buf, buf_size);
482 #define url_write_packet NULL
483 #endif //CONFIG_MUXERS
485 static int url_read_packet(void *opaque, uint8_t *buf, int buf_size)
487 URLContext *h = opaque;
488 return url_read(h, buf, buf_size);
491 static offset_t url_seek_packet(void *opaque, offset_t offset, int whence)
493 URLContext *h = opaque;
494 return url_seek(h, offset, whence);
498 int url_fdopen(ByteIOContext *s, URLContext *h)
501 int buffer_size, max_packet_size;
504 max_packet_size = url_get_max_packet_size(h);
505 if (max_packet_size) {
506 buffer_size = max_packet_size; /* no need to bufferize more than one packet */
508 buffer_size = IO_BUFFER_SIZE;
510 buffer = av_malloc(buffer_size);
514 if (init_put_byte(s, buffer, buffer_size,
515 (h->flags & URL_WRONLY || h->flags & URL_RDWR), h,
516 url_read_packet, url_write_packet, url_seek_packet) < 0) {
520 s->is_streamed = h->is_streamed;
521 s->max_packet_size = max_packet_size;
525 /* XXX: must be called before any I/O */
526 int url_setbufsize(ByteIOContext *s, int buf_size)
529 buffer = av_malloc(buf_size);
535 s->buffer_size = buf_size;
540 s->buf_end = buffer + buf_size;
544 /* NOTE: when opened as read/write, the buffers are only used for
546 int url_fopen(ByteIOContext *s, const char *filename, int flags)
551 err = url_open(&h, filename, flags);
554 err = url_fdopen(s, h);
562 int url_fclose(ByteIOContext *s)
564 URLContext *h = s->opaque;
567 memset(s, 0, sizeof(ByteIOContext));
571 URLContext *url_fileno(ByteIOContext *s)
577 /* XXX: currently size is limited */
578 int url_fprintf(ByteIOContext *s, const char *fmt, ...)
585 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
587 put_buffer(s, buf, strlen(buf));
590 #endif //CONFIG_MUXERS
592 /* note: unlike fgets, the EOL character is not returned and a whole
593 line is parsed. return NULL if first char read was EOF */
594 char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
604 if (c == EOF || c == '\n')
606 if ((q - buf) < buf_size - 1)
616 * Return the maximum packet size associated to packetized buffered file
617 * handle. If the file is not packetized (stream like http or file on
618 * disk), then 0 is returned.
620 * @param h buffered file handle
621 * @return maximum packet size in bytes
623 int url_fget_max_packet_size(ByteIOContext *s)
625 return s->max_packet_size;
628 /* url_open_dyn_buf and url_close_dyn_buf are used in rtp.c to send a response
629 * back to the server even if CONFIG_MUXERS is not set. */
630 #if defined(CONFIG_MUXERS) || defined(CONFIG_NETWORK)
631 /* buffer handling */
632 int url_open_buf(ByteIOContext *s, uint8_t *buf, int buf_size, int flags)
634 return init_put_byte(s, buf, buf_size,
635 (flags & URL_WRONLY || flags & URL_RDWR),
636 NULL, NULL, NULL, NULL);
639 /* return the written or read size */
640 int url_close_buf(ByteIOContext *s)
643 return s->buf_ptr - s->buffer;
646 /* output in a dynamic buffer */
648 typedef struct DynBuffer {
649 int pos, size, allocated_size;
652 uint8_t io_buffer[1];
655 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
657 DynBuffer *d = opaque;
658 int new_size, new_allocated_size;
660 /* reallocate buffer if needed */
661 new_size = d->pos + buf_size;
662 new_allocated_size = d->allocated_size;
663 if(new_size < d->pos || new_size > INT_MAX/2)
665 while (new_size > new_allocated_size) {
666 if (!new_allocated_size)
667 new_allocated_size = new_size;
669 new_allocated_size += new_allocated_size / 2 + 1;
672 if (new_allocated_size > d->allocated_size) {
673 d->buffer = av_realloc(d->buffer, new_allocated_size);
674 if(d->buffer == NULL)
676 d->allocated_size = new_allocated_size;
678 memcpy(d->buffer + d->pos, buf, buf_size);
680 if (d->pos > d->size)
685 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
687 unsigned char buf1[4];
690 /* packetized write: output the header */
691 buf1[0] = (buf_size >> 24);
692 buf1[1] = (buf_size >> 16);
693 buf1[2] = (buf_size >> 8);
694 buf1[3] = (buf_size);
695 ret= dyn_buf_write(opaque, buf1, 4);
700 return dyn_buf_write(opaque, buf, buf_size);
703 static offset_t dyn_buf_seek(void *opaque, offset_t offset, int whence)
705 DynBuffer *d = opaque;
707 if (whence == SEEK_CUR)
709 else if (whence == SEEK_END)
711 if (offset < 0 || offset > 0x7fffffffLL)
717 static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
720 int io_buffer_size, ret;
723 io_buffer_size = max_packet_size;
725 io_buffer_size = 1024;
727 if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
729 d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
732 d->io_buffer_size = io_buffer_size;
736 d->allocated_size = 0;
737 ret = init_put_byte(s, d->io_buffer, io_buffer_size,
739 max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
740 max_packet_size ? NULL : dyn_buf_seek);
742 s->max_packet_size = max_packet_size;
748 * Open a write only memory stream.
750 * @param s new IO context
751 * @return zero if no error.
753 int url_open_dyn_buf(ByteIOContext *s)
755 return url_open_dyn_buf_internal(s, 0);
759 * Open a write only packetized memory stream with a maximum packet
760 * size of 'max_packet_size'. The stream is stored in a memory buffer
761 * with a big endian 4 byte header giving the packet size in bytes.
763 * @param s new IO context
764 * @param max_packet_size maximum packet size (must be > 0)
765 * @return zero if no error.
767 int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
769 if (max_packet_size <= 0)
771 return url_open_dyn_buf_internal(s, max_packet_size);
775 * Return the written size and a pointer to the buffer. The buffer
776 * must be freed with av_free().
777 * @param s IO context
778 * @param pointer to a byte buffer
779 * @return the length of the byte buffer
781 int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer)
783 DynBuffer *d = s->opaque;
788 *pbuffer = d->buffer;
793 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */