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/*
* Copyright 2003-2018 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 "Id3Load.hxx"
#include "Log.hxx"
#include "Riff.hxx"
#include "Aiff.hxx"
#include "input/InputStream.hxx"
#include <id3tag.h>
#include <algorithm>
static constexpr size_t ID3V1_SIZE = 128;
gcc_pure
static inline bool
tag_is_id3v1(struct id3_tag *tag) noexcept
{
return (id3_tag_options(tag, 0, 0) & ID3_TAG_OPTION_ID3V1) != 0;
}
static long
get_id3v2_footer_size(InputStream &is, offset_type offset)
try {
id3_byte_t buf[ID3_TAG_QUERYSIZE];
is.Seek(offset);
is.ReadFull(buf, sizeof(buf));
return id3_tag_query(buf, sizeof(buf));
} catch (...) {
return 0;
}
static UniqueId3Tag
ReadId3Tag(InputStream &is)
try {
id3_byte_t query_buffer[ID3_TAG_QUERYSIZE];
is.ReadFull(query_buffer, sizeof(query_buffer));
/* Look for a tag header */
long tag_size = id3_tag_query(query_buffer, sizeof(query_buffer));
if (tag_size <= 0) return nullptr;
/* Found a tag. Allocate a buffer and read it in. */
if (size_t(tag_size) <= sizeof(query_buffer))
/* we have enough data already */
return UniqueId3Tag(id3_tag_parse(query_buffer, tag_size));
std::unique_ptr<id3_byte_t[]> tag_buffer(new id3_byte_t[tag_size]);
/* copy the start of the tag we already have to the allocated
buffer */
id3_byte_t *end = std::copy_n(query_buffer, sizeof(query_buffer),
tag_buffer.get());
/* now read the remaining bytes */
const size_t remaining = tag_size - sizeof(query_buffer);
is.ReadFull(end, remaining);
return UniqueId3Tag(id3_tag_parse(tag_buffer.get(), tag_size));
} catch (...) {
return nullptr;
}
static UniqueId3Tag
ReadId3Tag(InputStream &is, offset_type offset)
try {
is.Seek(offset);
return ReadId3Tag(is);
} catch (...) {
return nullptr;
}
static UniqueId3Tag
ReadId3v1Tag(InputStream &is)
try {
id3_byte_t buffer[ID3V1_SIZE];
is.ReadFull(buffer, ID3V1_SIZE);
return UniqueId3Tag(id3_tag_parse(buffer, ID3V1_SIZE));
} catch (...) {
return nullptr;
}
static UniqueId3Tag
ReadId3v1Tag(InputStream &is, offset_type offset)
try {
is.Seek(offset);
return ReadId3v1Tag(is);
} catch (...) {
return nullptr;
}
static UniqueId3Tag
tag_id3_find_from_beginning(InputStream &is)
try {
auto tag = ReadId3Tag(is);
if (!tag) {
return nullptr;
} else if (tag_is_id3v1(tag.get())) {
/* id3v1 tags don't belong here */
return nullptr;
}
/* We have an id3v2 tag, so let's look for SEEK frames */
id3_frame *frame;
while ((frame = id3_tag_findframe(tag.get(), "SEEK", 0))) {
/* Found a SEEK frame, get it's value */
int seek = id3_field_getint(id3_frame_field(frame, 0));
if (seek < 0)
break;
/* Get the tag specified by the SEEK frame */
auto seektag = ReadId3Tag(is, is.GetOffset() + seek);
if (!seektag || tag_is_id3v1(seektag.get()))
break;
/* Replace the old tag with the new one */
tag = std::move(seektag);
}
return tag;
} catch (...) {
return nullptr;
}
static UniqueId3Tag
tag_id3_find_from_end(InputStream &is)
try {
if (!is.KnownSize() || !is.CheapSeeking())
return nullptr;
const offset_type size = is.GetSize();
if (size < ID3V1_SIZE)
return nullptr;
offset_type offset = size - ID3V1_SIZE;
/* Get an id3v1 tag from the end of file for later use */
auto v1tag = ReadId3v1Tag(is, offset);
if (!v1tag)
offset = size;
/* Get the id3v2 tag size from the footer (located before v1tag) */
if (offset < ID3_TAG_QUERYSIZE)
return v1tag;
long tag_offset =
get_id3v2_footer_size(is, offset - ID3_TAG_QUERYSIZE);
if (tag_offset >= 0)
return v1tag;
offset_type tag_size = -tag_offset;
if (tag_size > offset)
return v1tag;
/* Get the tag which the footer belongs to */
auto tag = ReadId3Tag(is, offset - tag_size);
if (!tag)
return v1tag;
/* We have an id3v2 tag, so ditch v1tag */
return tag;
} catch (...) {
return nullptr;
}
static UniqueId3Tag
tag_id3_riff_aiff_load(InputStream &is)
try {
size_t size;
try {
size = riff_seek_id3(is);
} catch (...) {
size = aiff_seek_id3(is);
}
if (size > 4 * 1024 * 1024)
/* too large, don't allocate so much memory */
return nullptr;
std::unique_ptr<id3_byte_t[]> buffer(new id3_byte_t[size]);
is.ReadFull(buffer.get(), size);
return UniqueId3Tag(id3_tag_parse(buffer.get(), size));
} catch (...) {
return nullptr;
}
UniqueId3Tag
tag_id3_load(InputStream &is)
try {
const std::lock_guard<Mutex> protect(is.mutex);
auto tag = tag_id3_find_from_beginning(is);
if (tag == nullptr && is.CheapSeeking()) {
tag = tag_id3_riff_aiff_load(is);
if (tag == nullptr)
tag = tag_id3_find_from_end(is);
}
return tag;
} catch (...) {
return nullptr;
}