0,0 → 1,190 |
/* |
* Concat URL protocol |
* Copyright (c) 2006 Steve Lhomme |
* Copyright (c) 2007 Wolfram Gloger |
* Copyright (c) 2010 Michele OrrĂ¹ |
* |
* 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" |
#include "libavutil/avstring.h" |
#include "libavutil/mem.h" |
#include "url.h" |
|
#define AV_CAT_SEPARATOR "|" |
|
struct concat_nodes { |
URLContext *uc; ///< node's URLContext |
int64_t size; ///< url filesize |
}; |
|
struct concat_data { |
struct concat_nodes *nodes; ///< list of nodes to concat |
size_t length; ///< number of cat'ed nodes |
size_t current; ///< index of currently read node |
}; |
|
static av_cold int concat_close(URLContext *h) |
{ |
int err = 0; |
size_t i; |
struct concat_data *data = h->priv_data; |
struct concat_nodes *nodes = data->nodes; |
|
for (i = 0; i != data->length; i++) |
err |= ffurl_close(nodes[i].uc); |
|
av_freep(&data->nodes); |
|
return err < 0 ? -1 : 0; |
} |
|
static av_cold int concat_open(URLContext *h, const char *uri, int flags) |
{ |
char *node_uri = NULL; |
int err = 0; |
int64_t size; |
size_t len, i; |
URLContext *uc; |
struct concat_data *data = h->priv_data; |
struct concat_nodes *nodes; |
|
av_strstart(uri, "concat:", &uri); |
|
for (i = 0, len = 1; uri[i]; i++) |
if (uri[i] == *AV_CAT_SEPARATOR) |
/* integer overflow */ |
if (++len == UINT_MAX / sizeof(*nodes)) { |
av_freep(&h->priv_data); |
return AVERROR(ENAMETOOLONG); |
} |
|
if (!(nodes = av_realloc(NULL, sizeof(*nodes) * len))) { |
return AVERROR(ENOMEM); |
} else |
data->nodes = nodes; |
|
/* handle input */ |
if (!*uri) |
err = AVERROR(ENOENT); |
for (i = 0; *uri; i++) { |
/* parsing uri */ |
len = strcspn(uri, AV_CAT_SEPARATOR); |
if ((err = av_reallocp(&node_uri, len + 1)) < 0) |
break; |
av_strlcpy(node_uri, uri, len+1); |
uri += len + strspn(uri+len, AV_CAT_SEPARATOR); |
|
/* creating URLContext */ |
if ((err = ffurl_open(&uc, node_uri, flags, |
&h->interrupt_callback, NULL)) < 0) |
break; |
|
/* creating size */ |
if ((size = ffurl_size(uc)) < 0) { |
ffurl_close(uc); |
err = AVERROR(ENOSYS); |
break; |
} |
|
/* assembling */ |
nodes[i].uc = uc; |
nodes[i].size = size; |
} |
av_free(node_uri); |
data->length = i; |
|
if (err < 0) |
concat_close(h); |
else if (!(nodes = av_realloc(nodes, data->length * sizeof(*nodes)))) { |
concat_close(h); |
err = AVERROR(ENOMEM); |
} else |
data->nodes = nodes; |
return err; |
} |
|
static int concat_read(URLContext *h, unsigned char *buf, int size) |
{ |
int result, total = 0; |
struct concat_data *data = h->priv_data; |
struct concat_nodes *nodes = data->nodes; |
size_t i = data->current; |
|
while (size > 0) { |
result = ffurl_read(nodes[i].uc, buf, size); |
if (result < 0) |
return total ? total : result; |
if (!result) |
if (i + 1 == data->length || |
ffurl_seek(nodes[++i].uc, 0, SEEK_SET) < 0) |
break; |
total += result; |
buf += result; |
size -= result; |
} |
data->current = i; |
return total; |
} |
|
static int64_t concat_seek(URLContext *h, int64_t pos, int whence) |
{ |
int64_t result; |
struct concat_data *data = h->priv_data; |
struct concat_nodes *nodes = data->nodes; |
size_t i; |
|
switch (whence) { |
case SEEK_END: |
for (i = data->length - 1; |
i && pos < -nodes[i].size; |
i--) |
pos += nodes[i].size; |
break; |
case SEEK_CUR: |
/* get the absolute position */ |
for (i = 0; i != data->current; i++) |
pos += nodes[i].size; |
pos += ffurl_seek(nodes[i].uc, 0, SEEK_CUR); |
whence = SEEK_SET; |
/* fall through with the absolute position */ |
case SEEK_SET: |
for (i = 0; i != data->length - 1 && pos >= nodes[i].size; i++) |
pos -= nodes[i].size; |
break; |
default: |
return AVERROR(EINVAL); |
} |
|
result = ffurl_seek(nodes[i].uc, pos, whence); |
if (result >= 0) { |
data->current = i; |
while (i) |
result += nodes[--i].size; |
} |
return result; |
} |
|
URLProtocol ff_concat_protocol = { |
.name = "concat", |
.url_open = concat_open, |
.url_read = concat_read, |
.url_seek = concat_seek, |
.url_close = concat_close, |
.priv_data_size = sizeof(struct concat_data), |
}; |