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diff --git a/apps/metadata/ogg.c b/apps/metadata/ogg.c
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+/***************************************************************************
+ * __________ __ ___.
+ * 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 "logf.h"
+
+/* A simple parser to read vital metadata from an Ogg Speex file. Returns
+ * false if metadata needed by the Speex codec couldn't be read.
+ */
+
+bool get_speex_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 Speex has the following structure:
+ * 1) Identification header (containing samplerate, numchannels, etc)
+ Described in this page: (http://www.speex.org/manual2/node7.html)
+ * 2) Comment header - containing the Vorbis Comments
+ * 3) 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) < 33))
+ {
+ return false;
+ }
+
+ if ((memcmp(buf, "OggS", 4) != 0) || (memcmp(&buf[28], "Speex", 5) != 0))
+ {
+ return false;
+ }
+
+ /* 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]);
+ if ((lseek(fd, 33, SEEK_SET) < 0)||(read(fd, buf, 58) < 4))
+ {
+ return false;
+ }
+
+ id3->frequency = get_slong(&buf[31]);
+ last_serial = get_long_le(&buf[27]);/*temporary, header size*/
+ id3->bitrate = get_long_le(&buf[47]);
+ id3->vbr = get_long_le(&buf[55]);
+ id3->filesize = filesize(fd);
+ /* Comments are in second Ogg page */
+ if (lseek(fd, 28+last_serial/*(temporary for header size)*/, 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;
+ }
+ }
+
+ comment_size = remaining;
+
+ /* 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 = (id3->samples / id3->frequency) * 1000;
+ id3->bitrate = (((int64_t) id3->filesize - comment_size) * 8) / id3->length;
+ 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;
+}
+