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/*
* Copyright (C) 2003-2009 The Music Player Daemon Project
* http://www.musicpd.org
*
* 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 program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "tag_ape.h"
#include "tag.h"
#include <glib.h>
#include <assert.h>
#include <stdio.h>
struct tag *
tag_ape_load(const char *file)
{
struct tag *ret = NULL;
FILE *fp;
int tagCount;
char *buffer = NULL;
char *p;
size_t tagLen;
size_t size;
unsigned long flags;
int i;
char *key;
struct {
unsigned char id[8];
uint32_t version;
uint32_t length;
uint32_t tagCount;
unsigned char flags[4];
unsigned char reserved[8];
} footer;
const char *apeItems[7] = {
"title",
"artist",
"album",
"comment",
"genre",
"track",
"year"
};
int tagItems[7] = {
TAG_ITEM_TITLE,
TAG_ITEM_ARTIST,
TAG_ITEM_ALBUM,
TAG_ITEM_COMMENT,
TAG_ITEM_GENRE,
TAG_ITEM_TRACK,
TAG_ITEM_DATE,
};
fp = fopen(file, "r");
if (!fp)
return NULL;
/* determine if file has an apeV2 tag */
if (fseek(fp, 0, SEEK_END))
goto fail;
size = (size_t)ftell(fp);
if (fseek(fp, size - sizeof(footer), SEEK_SET))
goto fail;
if (fread(&footer, 1, sizeof(footer), fp) != sizeof(footer))
goto fail;
if (memcmp(footer.id, "APETAGEX", sizeof(footer.id)) != 0)
goto fail;
if (GUINT32_FROM_LE(footer.version) != 2000)
goto fail;
/* find beginning of ape tag */
tagLen = GUINT32_FROM_LE(footer.length);
if (tagLen <= sizeof(footer) + 10)
goto fail;
if (tagLen > 1024 * 1024)
/* refuse to load more than one megabyte of tag data */
goto fail;
if (fseek(fp, size - tagLen, SEEK_SET))
goto fail;
/* read tag into buffer */
tagLen -= sizeof(footer);
assert(tagLen > 10);
buffer = g_malloc(tagLen);
if (fread(buffer, 1, tagLen, fp) != tagLen)
goto fail;
/* read tags */
tagCount = GUINT32_FROM_LE(footer.tagCount);
p = buffer;
while (tagCount-- && tagLen > 10) {
size = GUINT32_FROM_LE(*(const uint32_t *)p);
p += 4;
tagLen -= 4;
flags = GUINT32_FROM_LE(*(const uint32_t *)p);
p += 4;
tagLen -= 4;
/* get the key */
key = p;
while (tagLen > size && *p != '\0') {
p++;
tagLen--;
}
p++;
tagLen--;
/* get the value */
if (tagLen < size)
goto fail;
/* we only care about utf-8 text tags */
if (!(flags & (0x3 << 1))) {
for (i = 0; i < 7; i++) {
if (g_ascii_strcasecmp(key, apeItems[i]) == 0) {
if (!ret)
ret = tag_new();
tag_add_item_n(ret, tagItems[i],
p, size);
}
}
}
p += size;
tagLen -= size;
}
fail:
if (fp)
fclose(fp);
g_free(buffer);
return ret;
}
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