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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2005 Dave Chapman
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* 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 "platform.h"
#include "metadata.h"
#include "metadata_common.h"
#include "metadata_parsers.h"
#include "logf.h"
bool get_flac_metadata(int fd, struct mp3entry* id3)
{
/* A simple parser to read vital metadata from a FLAC file - length,
* frequency, bitrate etc. This code should either be moved to a
* seperate file, or discarded in favour of the libFLAC code.
* The FLAC stream specification can be found at
* http://flac.sourceforge.net/format.html#stream
*/
/* Use the trackname part of the id3 structure as a temporary buffer */
unsigned char* buf = (unsigned char *)id3->path;
bool last_metadata = false;
bool rc = false;
if (!skip_id3v2(fd, id3) || (read(fd, buf, 4) < 4))
{
return rc;
}
if (memcmp(buf, "fLaC", 4) != 0)
{
return rc;
}
while (!last_metadata)
{
unsigned long i;
int type;
if (read(fd, buf, 4) < 0)
{
return rc;
}
last_metadata = buf[0] & 0x80;
type = buf[0] & 0x7f;
/* The length of the block */
i = (buf[1] << 16) | (buf[2] << 8) | buf[3];
if (type == 0) /* 0 is the STREAMINFO block */
{
unsigned long totalsamples;
if (i >= sizeof(id3->path) || read(fd, buf, i) < 0)
{
return rc;
}
id3->vbr = true; /* All FLAC files are VBR */
id3->filesize = filesize(fd);
id3->frequency = (buf[10] << 12) | (buf[11] << 4)
| ((buf[12] & 0xf0) >> 4);
rc = true; /* Got vital metadata */
/* totalsamples is a 36-bit field, but we assume <= 32 bits are used */
totalsamples = get_long_be(&buf[14]);
if(totalsamples > 0)
{
/* Calculate track length (in ms) and estimate the bitrate (in kbit/s) */
id3->length = ((int64_t) totalsamples * 1000) / id3->frequency;
id3->bitrate = (id3->filesize * 8) / id3->length;
}
else if (totalsamples == 0)
{
id3->length = 0;
id3->bitrate = 0;
}
else
{
logf("flac length invalid!");
return false;
}
}
else if (type == 4) /* 4 is the VORBIS_COMMENT block */
{
/* The next i bytes of the file contain the VORBIS COMMENTS. */
if (read_vorbis_tags(fd, id3, i) == 0)
{
return rc;
}
}
else if (!last_metadata)
{
/* Skip to next metadata block */
if (lseek(fd, i, SEEK_CUR) < 0)
{
return rc;
}
}
}
return true;
}
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