ref: 0637e2d9adc0744ae9d43702f7d882bd104106cd
dir: /src/id3.c/
/* libSoX MP3 utilities Copyright (c) 2007-9 SoX contributors
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or (at
* your option) any later version.
*
* This library 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 Lesser
* General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "sox_i.h"
#include "id3.h"
#ifdef HAVE_ID3TAG
#include <id3tag.h>
static char const * id3tagmap[][2] =
{
{"TIT2", "Title"},
{"TPE1", "Artist"},
{"TALB", "Album"},
{"TCOM", "Composer"},
{"TRCK", "Tracknumber"},
{"TDRC", "Year"},
{"TCON", "Genre"},
{"COMM", "Comment"},
{"TPOS", "Discnumber"},
{NULL, NULL}
};
static id3_utf8_t * utf8_id3tag_findframe(
struct id3_tag * tag, const char * const frameid, unsigned index)
{
struct id3_frame const * frame = id3_tag_findframe(tag, frameid, index);
if (frame) {
union id3_field const * field = id3_frame_field(frame, 1);
unsigned nstrings = id3_field_getnstrings(field);
while (nstrings--){
id3_ucs4_t const * ucs4 = id3_field_getstrings(field, nstrings);
if (ucs4)
return id3_ucs4_utf8duplicate(ucs4); /* Must call free() on this */
}
}
return NULL;
}
struct tag_info_node
{
struct tag_info_node * next;
off_t start;
off_t end;
};
struct tag_info {
sox_format_t * ft;
struct tag_info_node * head;
struct id3_tag * tag;
};
static int add_tag(struct tag_info * info)
{
struct tag_info_node * current;
off_t start, end;
id3_byte_t query[ID3_TAG_QUERYSIZE];
id3_byte_t * buffer;
long size;
int result = 0;
/* Ensure we're at the start of a valid tag and get its size. */
if (ID3_TAG_QUERYSIZE != lsx_readbuf(info->ft, query, ID3_TAG_QUERYSIZE) ||
!(size = id3_tag_query(query, ID3_TAG_QUERYSIZE))) {
return 0;
}
if (size < 0) {
if (0 != lsx_seeki(info->ft, size, SEEK_CUR) ||
ID3_TAG_QUERYSIZE != lsx_readbuf(info->ft, query, ID3_TAG_QUERYSIZE) ||
(size = id3_tag_query(query, ID3_TAG_QUERYSIZE)) <= 0) {
return 0;
}
}
/* Don't read a tag more than once. */
start = lsx_tell(info->ft);
end = start + size;
for (current = info->head; current; current = current->next) {
if (start == current->start && end == current->end) {
return 1;
} else if (start < current->end && current->start < end) {
return 0;
}
}
buffer = lsx_malloc((size_t)size);
if (!buffer) {
return 0;
}
memcpy(buffer, query, ID3_TAG_QUERYSIZE);
if ((unsigned long)size - ID3_TAG_QUERYSIZE ==
lsx_readbuf(info->ft, buffer + ID3_TAG_QUERYSIZE, (size_t)size - ID3_TAG_QUERYSIZE)) {
struct id3_tag * tag = id3_tag_parse(buffer, (size_t)size);
if (tag) {
current = lsx_malloc(sizeof(struct tag_info_node));
if (current) {
current->next = info->head;
current->start = start;
current->end = end;
info->head = current;
if (info->tag && (info->tag->extendedflags & ID3_TAG_EXTENDEDFLAG_TAGISANUPDATE)) {
struct id3_frame * frame;
unsigned i;
for (i = 0; (frame = id3_tag_findframe(tag, NULL, i)); i++) {
id3_tag_attachframe(info->tag, frame);
}
id3_tag_delete(tag);
} else {
if (info->tag) {
id3_tag_delete(info->tag);
}
info->tag = tag;
}
}
}
}
free(buffer);
return result;
}
void lsx_id3_read_tag(sox_format_t * ft, sox_bool search)
{
struct tag_info info;
id3_utf8_t * utf8;
int i;
int has_id3v1 = 0;
info.ft = ft;
info.head = NULL;
info.tag = NULL;
/*
We look for:
ID3v1 at end (EOF - 128).
ID3v2 at start.
ID3v2 at end (but before ID3v1 from end if there was one).
*/
if (search) {
if (0 == lsx_seeki(ft, -128, SEEK_END)) {
has_id3v1 =
add_tag(&info) &&
1 == ID3_TAG_VERSION_MAJOR(id3_tag_version(info.tag));
}
if (0 == lsx_seeki(ft, 0, SEEK_SET)) {
add_tag(&info);
}
if (0 == lsx_seeki(ft, has_id3v1 ? -138 : -10, SEEK_END)) {
add_tag(&info);
}
} else {
add_tag(&info);
}
if (info.tag && info.tag->frames) {
for (i = 0; id3tagmap[i][0]; ++i) {
if ((utf8 = utf8_id3tag_findframe(info.tag, id3tagmap[i][0], 0))) {
char * comment = lsx_malloc(strlen(id3tagmap[i][1]) + 1 + strlen((char *)utf8) + 1);
sprintf(comment, "%s=%s", id3tagmap[i][1], utf8);
sox_append_comment(&ft->oob.comments, comment);
free(comment);
free(utf8);
}
}
if ((utf8 = utf8_id3tag_findframe(info.tag, "TLEN", 0))) {
unsigned long tlen = strtoul((char *)utf8, NULL, 10);
if (tlen > 0 && tlen < ULONG_MAX) {
ft->signal.length= tlen; /* In ms; convert to samples later */
lsx_debug("got exact duration from ID3 TLEN");
}
free(utf8);
}
}
while (info.head) {
struct tag_info_node * head = info.head;
info.head = head->next;
free(head);
}
if (info.tag) {
id3_tag_delete(info.tag);
}
}
#else
/* Stub for format modules */
void lsx_id3_read_tag(sox_format_t *ft, sox_bool search) { }
#endif