mpd/src/IcyMetaDataParser.cxx
2013-10-20 13:32:59 +02:00

174 lines
3.5 KiB
C++

/*
* Copyright (C) 2003-2013 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 "IcyMetaDataParser.hxx"
#include "tag/Tag.hxx"
#include "util/Domain.hxx"
#include "Log.hxx"
#include <glib.h>
#include <assert.h>
#include <string.h>
static constexpr Domain icy_metadata_domain("icy_metadata");
void
IcyMetaDataParser::Reset()
{
if (!IsDefined())
return;
if (data_rest == 0 && meta_size > 0)
g_free(meta_data);
delete tag;
data_rest = data_size;
meta_size = 0;
}
size_t
IcyMetaDataParser::Data(size_t length)
{
assert(length > 0);
if (!IsDefined())
return length;
if (data_rest == 0)
return 0;
if (length >= data_rest) {
length = data_rest;
data_rest = 0;
} else
data_rest -= length;
return length;
}
static void
icy_add_item(Tag &tag, TagType type, const char *value)
{
size_t length = strlen(value);
if (length >= 2 && value[0] == '\'' && value[length - 1] == '\'') {
/* strip the single quotes */
++value;
length -= 2;
}
if (length > 0)
tag.AddItem(type, value, length);
}
static void
icy_parse_tag_item(Tag &tag, const char *item)
{
gchar **p = g_strsplit(item, "=", 0);
if (p[0] != nullptr && p[1] != nullptr) {
if (strcmp(p[0], "StreamTitle") == 0)
icy_add_item(tag, TAG_TITLE, p[1]);
else
FormatDebug(icy_metadata_domain,
"unknown icy-tag: '%s'", p[0]);
}
g_strfreev(p);
}
static Tag *
icy_parse_tag(const char *p)
{
Tag *tag = new Tag();
gchar **items = g_strsplit(p, ";", 0);
for (unsigned i = 0; items[i] != nullptr; ++i)
icy_parse_tag_item(*tag, items[i]);
g_strfreev(items);
return tag;
}
size_t
IcyMetaDataParser::Meta(const void *data, size_t length)
{
const unsigned char *p = (const unsigned char *)data;
assert(IsDefined());
assert(data_rest == 0);
assert(length > 0);
if (meta_size == 0) {
/* read meta_size from the first byte of a meta
block */
meta_size = *p++ * 16;
if (meta_size == 0) {
/* special case: no metadata */
data_rest = data_size;
return 1;
}
/* 1 byte was consumed (must be re-added later for the
return value */
--length;
/* initialize metadata reader, allocate enough
memory (+1 for the null terminator) */
meta_position = 0;
meta_data = (char *)g_malloc(meta_size + 1);
}
assert(meta_position < meta_size);
if (length > meta_size - meta_position)
length = meta_size - meta_position;
memcpy(meta_data + meta_position, p, length);
meta_position += length;
if (p != data)
/* re-add the first byte (which contained meta_size) */
++length;
if (meta_position == meta_size) {
/* null-terminate the string */
meta_data[meta_size] = 0;
/* parse */
delete tag;
tag = icy_parse_tag(meta_data);
g_free(meta_data);
/* change back to normal data mode */
meta_size = 0;
data_rest = data_size;
}
return length;
}