ffmpeg-2.8.5

git-svn-id: svn://kolibrios.org@6147 a494cfbc-eb01-0410-851d-a64ba20cac60

contrib/sdk/sources/ffmpeg/ffmpeg-2.8/libavformat/concat.c

@@ -0,0 +1,192 @@
+/*
+ * Concat URL protocol
+ * Copyright (c) 2006 Steve Lhomme
+ * Copyright (c) 2007 Wolfram Gloger
+ * Copyright (c) 2010 Michele Orrù
+ *
+ * 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 "libavutil/avstring.h"
+#include "libavutil/mem.h"
+
+#include "avformat.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),
+};