1 files changed, 330 insertions, 0 deletions

diff --git a/apps/metadata/vorbis.c b/apps/metadata/vorbis.c
new file mode 100644
index 0000000000..5112615e47
--- /dev/null
+++ b/apps/metadata/vorbis.c
@@ -0,0 +1,330 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2005 Dave Chapman
+ *
+ * All files in this archive are subject to the GNU General Public License.
+ * See the file COPYING in the source tree root for full license agreement.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <inttypes.h>
+
+#include "system.h"
+#include "id3.h"
+#include "metadata_common.h"
+#include "metadata_parsers.h"
+#include "structec.h"
+#include "logf.h"
+
+/* Read the items in a Vorbis comment packet. Returns true the items were
+ * fully read, false otherwise.
+ */
+bool read_vorbis_tags(int fd, struct mp3entry *id3, 
+    long tag_remaining)
+{
+    char *buf = id3->id3v2buf;
+    int32_t comment_count;
+    int32_t len;
+    int buf_remaining = sizeof(id3->id3v2buf) + sizeof(id3->id3v1buf);
+    int i;
+
+    if (ecread(fd, &len, 1, "l", IS_BIG_ENDIAN) < (long) sizeof(len)) 
+    {
+        return false;
+    }
+    
+    if ((lseek(fd, len, SEEK_CUR) < 0)
+        || (ecread(fd, &comment_count, 1, "l", IS_BIG_ENDIAN) 
+            < (long) sizeof(comment_count)))
+    {
+        return false;
+    }
+    
+    tag_remaining -= len + sizeof(len) + sizeof(comment_count);
+
+    if (tag_remaining <= 0)
+    {
+        return true;
+    }
+
+    for (i = 0; i < comment_count; i++)
+    {
+        char name[TAG_NAME_LENGTH];
+        char value[TAG_VALUE_LENGTH];
+        int32_t read_len;
+
+        if (tag_remaining < 4) 
+        {
+            break;
+        }
+
+        if (ecread(fd, &len, 1, "l", IS_BIG_ENDIAN) < (long) sizeof(len))
+        {
+            return false;
+        }
+
+        tag_remaining -= 4;
+
+        /* Quit if we've passed the end of the page */
+        if (tag_remaining < len)
+        {
+            break;
+        }
+
+        tag_remaining -= len;
+        read_len = read_string(fd, name, sizeof(name), '=', len);
+        
+        if (read_len < 0)
+        {
+            return false;
+        }
+
+        len -= read_len;
+
+        if (read_string(fd, value, sizeof(value), -1, len) < 0)
+        {
+            return false;
+        }
+
+        len = parse_tag(name, value, id3, buf, buf_remaining, 
+            TAGTYPE_VORBIS);
+        buf += len;
+        buf_remaining -= len;
+    }
+
+    /* Skip to the end of the block */
+    if (tag_remaining) 
+    {
+        if (lseek(fd, tag_remaining, SEEK_CUR) < 0)
+        {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+/* A simple parser to read vital metadata from an Ogg Vorbis file. 
+ * Calls get_speex_metadata if a speex file is identified. Returns
+ * false if metadata needed by the Vorbis codec couldn't be read.
+ */
+bool get_vorbis_metadata(int fd, struct mp3entry* id3)
+{
+    /* An Ogg File is split into pages, each starting with the string 
+     * "OggS". Each page has a timestamp (in PCM samples) referred to as
+     * the "granule position".
+     *
+     * An Ogg Vorbis has the following structure:
+     * 1) Identification header (containing samplerate, numchannels, etc)
+     * 2) Comment header - containing the Vorbis Comments
+     * 3) Setup header - containing codec setup information
+     * 4) Many audio packets...
+     */
+
+    /* Use the path name of the id3 structure as a temporary buffer. */
+    unsigned char* buf = (unsigned char *)id3->path;
+    long comment_size;
+    long remaining = 0;
+    long last_serial = 0;
+    long serial, r;
+    int segments;
+    int i;
+    bool eof = false;
+
+    if ((lseek(fd, 0, SEEK_SET) < 0) || (read(fd, buf, 58) < 4))
+    {
+        return false;
+    }
+    
+    if ((memcmp(buf, "OggS", 4) != 0) || (memcmp(&buf[29], "vorbis", 6) != 0))
+    {
+        if ((memcmp(buf, "OggS", 4) != 0) || (memcmp(&buf[28], "Speex", 5) != 0))
+        {        
+            return false;
+        }
+        else
+        {
+            id3->codectype = AFMT_SPEEX;
+            return get_speex_metadata(fd, id3);
+        }
+    }
+    
+    /* We need to ensure the serial number from this page is the same as the
+     * one from the last page (since we only support a single bitstream).
+     */
+    serial = get_long_le(&buf[14]);
+    id3->frequency = get_long_le(&buf[40]);
+    id3->filesize = filesize(fd);
+
+    /* Comments are in second Ogg page */
+    if (lseek(fd, 58, SEEK_SET) < 0)
+    {
+        return false;
+    }
+
+    /* Minimum header length for Ogg pages is 27. */
+    if (read(fd, buf, 27) < 27) 
+    {
+        return false;
+    }
+
+    if (memcmp(buf, "OggS", 4) !=0 )
+    {
+        return false;
+    }
+
+    segments = buf[26];
+
+    /* read in segment table */
+    if (read(fd, buf, segments) < segments) 
+    {
+        return false;
+    }
+
+    /* The second packet in a vorbis stream is the comment packet. It *may*
+     * extend beyond the second page, but usually does not. Here we find the
+     * length of the comment packet (or the rest of the page if the comment
+     * packet extends to the third page).
+     */
+    for (i = 0; i < segments; i++) 
+    {
+        remaining += buf[i];
+        
+        /* The last segment of a packet is always < 255 bytes */
+        if (buf[i] < 255) 
+        {
+              break;
+        }
+    }
+
+    /* Now read in packet header (type and id string) */
+    if (read(fd, buf, 7) < 7) 
+    {
+        return false;
+    }
+
+    comment_size = remaining;
+    remaining -= 7;
+
+    /* The first byte of a packet is the packet type; comment packets are
+     * type 3.
+     */
+    if ((buf[0] != 3) || (memcmp(buf + 1, "vorbis", 6) !=0))
+    {
+        return false;
+    }
+
+    /* Failure to read the tags isn't fatal. */
+    read_vorbis_tags(fd, id3, remaining);
+
+    /* We now need to search for the last page in the file - identified by 
+     * by ('O','g','g','S',0) and retrieve totalsamples.
+     */
+
+    /* A page is always < 64 kB */
+    if (lseek(fd, -(MIN(64 * 1024, id3->filesize)), SEEK_END) < 0)
+    {
+        return false;
+    }
+
+    remaining = 0;
+
+    while (!eof) 
+    {
+        r = read(fd, &buf[remaining], MAX_PATH - remaining);
+        
+        if (r <= 0) 
+        {
+            eof = true;
+        } 
+        else 
+        {
+            remaining += r;
+        }
+        
+        /* Inefficient (but simple) search */
+        i = 0;
+        
+        while (i < (remaining - 3)) 
+        {
+            if ((buf[i] == 'O') && (memcmp(&buf[i], "OggS", 4) == 0))
+            {
+                if (i < (remaining - 17)) 
+                {
+                    /* Note that this only reads the low 32 bits of a
+                     * 64 bit value.
+                     */
+                     id3->samples = get_long_le(&buf[i + 6]);
+                     last_serial = get_long_le(&buf[i + 14]);
+
+                    /* If this page is very small the beginning of the next
+                     * header could be in buffer. Jump near end of this header
+                     * and continue */
+                    i += 27;
+                } 
+                else 
+                {
+                    break;
+                }
+            } 
+            else 
+            {
+                i++;
+            }
+        }
+
+        if (i < remaining) 
+        {
+            /* Move the remaining bytes to start of buffer.
+             * Reuse var 'segments' as it is no longer needed */
+            segments = 0;
+            while (i < remaining)
+            {
+                buf[segments++] = buf[i++];
+            }
+            remaining = segments;
+        }
+        else
+        {
+            /* Discard the rest of the buffer */
+            remaining = 0;
+        }
+    }
+
+    /* This file has mutiple vorbis bitstreams (or is corrupt). */
+    /* FIXME we should display an error here. */
+    if (serial != last_serial)
+    {
+        logf("serialno mismatch");
+        logf("%ld", serial);
+        logf("%ld", last_serial);
+        return false;
+    }
+
+    id3->length = ((int64_t) id3->samples * 1000) / id3->frequency;
+
+    if (id3->length <= 0)
+    {
+        logf("ogg length invalid!");
+        return false;
+    }
+    
+    id3->bitrate = (((int64_t) id3->filesize - comment_size) * 8) / id3->length;
+    id3->vbr = true;
+    
+    return true;
+}
+