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/*
* Unbuffered io for ffmpeg system
* Copyright (c) 2001 Fabrice Bellard
*
* This file is part of FFmpeg.
*
* FFmpeg 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 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avformat.h"
static int default_interrupt_cb(void);
URLProtocol *first_protocol = NULL;
URLInterruptCB *url_interrupt_cb = default_interrupt_cb;
int register_protocol(URLProtocol *protocol)
{
URLProtocol **p;
p = &first_protocol;
while (*p != NULL) p = &(*p)->next;
*p = protocol;
protocol->next = NULL;
return 0;
}
int url_open(URLContext **puc, const char *filename, int flags)
{
URLContext *uc;
URLProtocol *up;
const char *p;
char proto_str[128], *q;
int err;
p = filename;
q = proto_str;
while (*p != '\0' && *p != ':') {
/* protocols can only contain alphabetic chars */
if (!isalpha(*p))
goto file_proto;
if ((q - proto_str) < sizeof(proto_str) - 1)
*q++ = *p;
p++;
}
/* if the protocol has length 1, we consider it is a dos drive */
if (*p == '\0' || (q - proto_str) <= 1) {
file_proto:
strcpy(proto_str, "file");
} else {
*q = '\0';
}
up = first_protocol;
while (up != NULL) {
if (!strcmp(proto_str, up->name))
goto found;
up = up->next;
}
err = -ENOENT;
goto fail;
found:
uc = av_malloc(sizeof(URLContext) + strlen(filename) + 1);
if (!uc) {
err = -ENOMEM;
goto fail;
}
#if LIBAVFORMAT_VERSION_INT >= (52<<16)
uc->filename = (char *) &uc[1];
#endif
strcpy(uc->filename, filename);
uc->prot = up;
uc->flags = flags;
uc->is_streamed = 0; /* default = not streamed */
uc->max_packet_size = 0; /* default: stream file */
err = up->url_open(uc, filename, flags);
if (err < 0) {
av_free(uc);
*puc = NULL;
return err;
}
*puc = uc;
return 0;
fail:
*puc = NULL;
return err;
}
int url_read(URLContext *h, unsigned char *buf, int size)
{
int ret;
if (h->flags & URL_WRONLY)
return AVERROR_IO;
ret = h->prot->url_read(h, buf, size);
return ret;
}
#if defined(CONFIG_MUXERS) || defined(CONFIG_PROTOCOLS)
int url_write(URLContext *h, unsigned char *buf, int size)
{
int ret;
if (!(h->flags & (URL_WRONLY | URL_RDWR)))
return AVERROR_IO;
/* avoid sending too big packets */
if (h->max_packet_size && size > h->max_packet_size)
return AVERROR_IO;
ret = h->prot->url_write(h, buf, size);
return ret;
}
#endif //CONFIG_MUXERS || CONFIG_PROTOCOLS
offset_t url_seek(URLContext *h, offset_t pos, int whence)
{
offset_t ret;
if (!h->prot->url_seek)
return -EPIPE;
ret = h->prot->url_seek(h, pos, whence);
return ret;
}
int url_close(URLContext *h)
{
int ret;
ret = h->prot->url_close(h);
av_free(h);
return ret;
}
int url_exist(const char *filename)
{
URLContext *h;
if (url_open(&h, filename, URL_RDONLY) < 0)
return 0;
url_close(h);
return 1;
}
offset_t url_filesize(URLContext *h)
{
offset_t pos, size;
size= url_seek(h, 0, AVSEEK_SIZE);
if(size<0){
pos = url_seek(h, 0, SEEK_CUR);
if ((size = url_seek(h, -1, SEEK_END)) < 0)
return size;
size++;
url_seek(h, pos, SEEK_SET);
}
return size;
}
/*
* Return the maximum packet size associated to packetized file
* handle. If the file is not packetized (stream like http or file on
* disk), then 0 is returned.
*
* @param h file handle
* @return maximum packet size in bytes
*/
int url_get_max_packet_size(URLContext *h)
{
return h->max_packet_size;
}
void url_get_filename(URLContext *h, char *buf, int buf_size)
{
pstrcpy(buf, buf_size, h->filename);
}
static int default_interrupt_cb(void)
{
return 0;
}
/**
* The callback is called in blocking functions to test regulary if
* asynchronous interruption is needed. -EINTR is returned in this
* case by the interrupted function. 'NULL' means no interrupt
* callback is given.
*/
void url_set_interrupt_cb(URLInterruptCB *interrupt_cb)
{
if (!interrupt_cb)
interrupt_cb = default_interrupt_cb;
url_interrupt_cb = interrupt_cb;
}
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