mpd/src/AudioParser.cxx

166 lines
3.6 KiB
C++

/*
* Copyright 2003-2017 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.
*/
/*
* Parser functions for audio related objects.
*
*/
#include "config.h"
#include "AudioParser.hxx"
#include "AudioFormat.hxx"
#include "util/RuntimeError.hxx"
#include <assert.h>
#include <string.h>
#include <stdlib.h>
static uint32_t
ParseSampleRate(const char *src, bool mask, const char **endptr_r)
{
unsigned long value;
char *endptr;
if (mask && *src == '*') {
*endptr_r = src + 1;
return 0;
}
value = strtoul(src, &endptr, 10);
if (endptr == src) {
throw std::runtime_error("Failed to parse the sample rate");
} else if (!audio_valid_sample_rate(value))
throw FormatRuntimeError("Invalid sample rate: %lu",
value);
*endptr_r = endptr;
return value;
}
static SampleFormat
ParseSampleFormat(const char *src, bool mask, const char **endptr_r)
{
unsigned long value;
char *endptr;
SampleFormat sample_format;
if (mask && *src == '*') {
*endptr_r = src + 1;
return SampleFormat::UNDEFINED;
}
if (*src == 'f') {
*endptr_r = src + 1;
return SampleFormat::FLOAT;
}
if (memcmp(src, "dsd", 3) == 0) {
*endptr_r = src + 3;
return SampleFormat::DSD;
}
value = strtoul(src, &endptr, 10);
if (endptr == src)
throw std::runtime_error("Failed to parse the sample format");
switch (value) {
case 8:
sample_format = SampleFormat::S8;
break;
case 16:
sample_format = SampleFormat::S16;
break;
case 24:
if (memcmp(endptr, "_3", 2) == 0)
/* for backwards compatibility */
endptr += 2;
sample_format = SampleFormat::S24_P32;
break;
case 32:
sample_format = SampleFormat::S32;
break;
default:
throw FormatRuntimeError("Invalid sample format: %lu", value);
}
assert(audio_valid_sample_format(sample_format));
*endptr_r = endptr;
return sample_format;
}
static uint8_t
ParseChannelCount(const char *src, bool mask, const char **endptr_r)
{
unsigned long value;
char *endptr;
if (mask && *src == '*') {
*endptr_r = src + 1;
return 0;
}
value = strtoul(src, &endptr, 10);
if (endptr == src)
throw std::runtime_error("Failed to parse the channel count");
else if (!audio_valid_channel_count(value))
throw FormatRuntimeError("Invalid channel count: %u", value);
*endptr_r = endptr;
return value;
}
AudioFormat
ParseAudioFormat(const char *src, bool mask)
{
AudioFormat dest;
dest.Clear();
/* parse sample rate */
dest.sample_rate = ParseSampleRate(src, mask, &src);
if (*src++ != ':')
throw std::runtime_error("Sample format missing");
/* parse sample format */
dest.format = ParseSampleFormat(src, mask, &src);
if (*src++ != ':')
throw std::runtime_error("Channel count missing");
/* parse channel count */
dest.channels = ParseChannelCount(src, mask, &src);
if (*src != 0)
throw FormatRuntimeError("Extra data after channel count: %s", src);
assert(mask
? dest.IsMaskValid()
: dest.IsValid());
return dest;
}