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/*
* Unbuffered io for ffmpeg system
* Copyright (c) 2001 Gerard Lantau
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "avformat.h"
URLProtocol *first_protocol = NULL;
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 != ':') {
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) {
strcpy(proto_str, "file");
} else {
*q = '\0';
}
up = first_protocol;
while (up != NULL) {
if (!strcmp(proto_str, up->name))
goto found;
up = up->next;
}
return -ENOENT;
found:
uc = av_malloc(sizeof(URLContext));
if (!uc)
return -ENOMEM;
uc->prot = up;
uc->flags = flags;
uc->is_streamed = 0; /* default = not streamed */
uc->packet_size = 1; /* default packet size */
err = up->url_open(uc, filename, flags);
if (err < 0) {
av_free(uc);
*puc = NULL;
return err;
}
*puc = uc;
return 0;
}
int url_read(URLContext *h, unsigned char *buf, int size)
{
int ret;
if (h->flags & URL_WRONLY)
return -EIO;
ret = h->prot->url_read(h, buf, size);
return ret;
}
int url_write(URLContext *h, unsigned char *buf, int size)
{
int ret;
if (!(h->flags & URL_WRONLY))
return -EIO;
ret = h->prot->url_write(h, buf, size);
return ret;
}
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;
pos = url_seek(h, 0, SEEK_CUR);
size = url_seek(h, 0, SEEK_END);
url_seek(h, pos, SEEK_SET);
return size;
}
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