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/*
* Copyright (C) 2003-2011 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 "config.h"
#include "ape.h"
#include <glib.h>
#include <stdint.h>
#include <assert.h>
#include <stdio.h>
#include <string.h>
struct ape_footer {
unsigned char id[8];
uint32_t version;
uint32_t length;
uint32_t count;
unsigned char flags[4];
unsigned char reserved[8];
};
static bool
ape_scan_internal(FILE *fp, tag_ape_callback_t callback, void *ctx)
{
/* determine if file has an apeV2 tag */
struct ape_footer footer;
if (fseek(fp, -(long)sizeof(footer), SEEK_END) ||
fread(&footer, 1, sizeof(footer), fp) != sizeof(footer) ||
memcmp(footer.id, "APETAGEX", sizeof(footer.id)) != 0 ||
GUINT32_FROM_LE(footer.version) != 2000)
return false;
/* find beginning of ape tag */
size_t remaining = GUINT32_FROM_LE(footer.length);
if (remaining <= sizeof(footer) + 10 ||
/* refuse to load more than one megabyte of tag data */
remaining > 1024 * 1024 ||
fseek(fp, -(long)remaining, SEEK_END))
return false;
/* read tag into buffer */
remaining -= sizeof(footer);
assert(remaining > 10);
char *buffer = g_malloc(remaining);
if (fread(buffer, 1, remaining, fp) != remaining) {
g_free(buffer);
return false;
}
/* read tags */
unsigned n = GUINT32_FROM_LE(footer.count);
const char *p = buffer;
while (n-- && remaining > 10) {
size_t size = GUINT32_FROM_LE(*(const uint32_t *)p);
p += 4;
remaining -= 4;
unsigned long flags = GUINT32_FROM_LE(*(const uint32_t *)p);
p += 4;
remaining -= 4;
/* get the key */
const char *key = p;
while (remaining > size && *p != '\0') {
p++;
remaining--;
}
p++;
remaining--;
/* get the value */
if (remaining < size)
break;
if (!callback(flags, key, p, size, ctx))
break;
p += size;
remaining -= size;
}
g_free(buffer);
return true;
}
bool
tag_ape_scan(const char *path_fs, tag_ape_callback_t callback, void *ctx)
{
FILE *fp;
fp = fopen(path_fs, "rb");
if (fp == NULL)
return false;
bool success = ape_scan_internal(fp, callback, ctx);
fclose(fp);
return success;
}
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