mpd/src/tag/Aiff.cxx
2014-01-13 22:31:55 +01:00

99 lines
2.4 KiB
C++

/*
* Copyright (C) 2003-2014 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" /* must be first for large file support */
#include "Aiff.hxx"
#include "util/Domain.hxx"
#include "system/ByteOrder.hxx"
#include "Log.hxx"
#include <limits>
#include <stdint.h>
#include <sys/stat.h>
#include <string.h>
static constexpr Domain aiff_domain("aiff");
struct aiff_header {
char id[4];
uint32_t size;
char format[4];
};
struct aiff_chunk_header {
char id[4];
uint32_t size;
};
size_t
aiff_seek_id3(FILE *file)
{
/* determine the file size */
struct stat st;
if (fstat(fileno(file), &st) < 0) {
LogErrno(aiff_domain, "Failed to stat file descriptor");
return 0;
}
/* seek to the beginning and read the AIFF header */
if (fseek(file, 0, SEEK_SET) != 0) {
LogErrno(aiff_domain, "Failed to seek");
return 0;
}
aiff_header header;
size_t size = fread(&header, sizeof(header), 1, file);
if (size != 1 ||
memcmp(header.id, "FORM", 4) != 0 ||
FromBE32(header.size) > (uint32_t)st.st_size ||
(memcmp(header.format, "AIFF", 4) != 0 &&
memcmp(header.format, "AIFC", 4) != 0))
/* not a AIFF file */
return 0;
while (true) {
/* read the chunk header */
aiff_chunk_header chunk;
size = fread(&chunk, sizeof(chunk), 1, file);
if (size != 1)
return 0;
size = FromBE32(chunk.size);
if (size > unsigned(std::numeric_limits<int>::max()))
/* too dangerous, bail out: possible integer
underflow when casting to off_t */
return 0;
if (size % 2 != 0)
/* pad byte */
++size;
if (memcmp(chunk.id, "ID3 ", 4) == 0)
/* found it! */
return size;
if (fseek(file, size, SEEK_CUR) != 0)
return 0;
}
}