renamed libav to libavformat

Originally committed as revision 1276 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/avio.c

@@ -0,0 +1,156 @@
+/*
+ * Unbuffered io for ffmpeg system
+ * Copyright (c) 2001 Fabrice Bellard
+ *
+ * This library 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 of the License, or (at your option) any later version.
+ *
+ * This library 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  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;
+    }
+    err = -ENOENT;
+    goto fail;
+ found:
+    uc = av_malloc(sizeof(URLContext));
+    if (!uc) {
+        err = -ENOMEM;
+        goto fail;
+    }
+    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 -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 | URL_RDWR)))
+        return -EIO;
+    /* avoid sending too big packets */
+    if (h->max_packet_size && size > h->max_packet_size)
+        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;
+}
+
+/* 
+ * 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;
+}