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Diffstat (limited to 'src/decoder/plugins/Mpg123DecoderPlugin.cxx')
-rw-r--r-- | src/decoder/plugins/Mpg123DecoderPlugin.cxx | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/src/decoder/plugins/Mpg123DecoderPlugin.cxx b/src/decoder/plugins/Mpg123DecoderPlugin.cxx new file mode 100644 index 000000000..013155bf5 --- /dev/null +++ b/src/decoder/plugins/Mpg123DecoderPlugin.cxx @@ -0,0 +1,261 @@ +/* + * 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 "Mpg123DecoderPlugin.hxx" +#include "../DecoderAPI.hxx" +#include "CheckAudioFormat.hxx" +#include "tag/TagHandler.hxx" +#include "fs/Path.hxx" +#include "util/Error.hxx" +#include "util/Domain.hxx" +#include "Log.hxx" + +#include <mpg123.h> + +#include <stdio.h> + +static constexpr Domain mpg123_domain("mpg123"); + +static bool +mpd_mpg123_init(gcc_unused const config_param ¶m) +{ + mpg123_init(); + + return true; +} + +static void +mpd_mpg123_finish(void) +{ + mpg123_exit(); +} + +/** + * Opens a file with an existing #mpg123_handle. + * + * @param handle a handle which was created before; on error, this + * function will not free it + * @param audio_format this parameter is filled after successful + * return + * @return true on success + */ +static bool +mpd_mpg123_open(mpg123_handle *handle, const char *path_fs, + AudioFormat &audio_format) +{ + int error; + int channels, encoding; + long rate; + + /* mpg123_open() wants a writable string :-( */ + char *const path2 = const_cast<char *>(path_fs); + + error = mpg123_open(handle, path2); + if (error != MPG123_OK) { + FormatWarning(mpg123_domain, + "libmpg123 failed to open %s: %s", + path_fs, mpg123_plain_strerror(error)); + return false; + } + + /* obtain the audio format */ + + error = mpg123_getformat(handle, &rate, &channels, &encoding); + if (error != MPG123_OK) { + FormatWarning(mpg123_domain, + "mpg123_getformat() failed: %s", + mpg123_plain_strerror(error)); + return false; + } + + if (encoding != MPG123_ENC_SIGNED_16) { + /* other formats not yet implemented */ + FormatWarning(mpg123_domain, + "expected MPG123_ENC_SIGNED_16, got %d", + encoding); + return false; + } + + Error error2; + if (!audio_format_init_checked(audio_format, rate, SampleFormat::S16, + channels, error2)) { + LogError(error2); + return false; + } + + return true; +} + +static void +mpd_mpg123_file_decode(Decoder &decoder, Path path_fs) +{ + mpg123_handle *handle; + int error; + off_t num_samples; + struct mpg123_frameinfo info; + + /* open the file */ + + handle = mpg123_new(nullptr, &error); + if (handle == nullptr) { + FormatError(mpg123_domain, + "mpg123_new() failed: %s", + mpg123_plain_strerror(error)); + return; + } + + AudioFormat audio_format; + if (!mpd_mpg123_open(handle, path_fs.c_str(), audio_format)) { + mpg123_delete(handle); + return; + } + + num_samples = mpg123_length(handle); + + /* tell MPD core we're ready */ + + const auto duration = + SongTime::FromScale<uint64_t>(num_samples, + audio_format.sample_rate); + + decoder_initialized(decoder, audio_format, true, duration); + + if (mpg123_info(handle, &info) != MPG123_OK) { + info.vbr = MPG123_CBR; + info.bitrate = 0; + } + + switch (info.vbr) { + case MPG123_ABR: + info.bitrate = info.abr_rate; + break; + case MPG123_CBR: + break; + default: + info.bitrate = 0; + } + + /* the decoder main loop */ + + DecoderCommand cmd; + do { + unsigned char buffer[8192]; + size_t nbytes; + + /* decode */ + + error = mpg123_read(handle, buffer, sizeof(buffer), &nbytes); + if (error != MPG123_OK) { + if (error != MPG123_DONE) + FormatWarning(mpg123_domain, + "mpg123_read() failed: %s", + mpg123_plain_strerror(error)); + break; + } + + /* update bitrate for ABR/VBR */ + if (info.vbr != MPG123_CBR) { + /* FIXME: maybe skip, as too expensive? */ + /* FIXME: maybe, (info.vbr == MPG123_VBR) ? */ + if (mpg123_info (handle, &info) != MPG123_OK) + info.bitrate = 0; + } + + /* send to MPD */ + + cmd = decoder_data(decoder, nullptr, buffer, nbytes, info.bitrate); + + if (cmd == DecoderCommand::SEEK) { + off_t c = decoder_seek_where_frame(decoder); + c = mpg123_seek(handle, c, SEEK_SET); + if (c < 0) + decoder_seek_error(decoder); + else { + decoder_command_finished(decoder); + decoder_timestamp(decoder, c/(double)audio_format.sample_rate); + } + + cmd = DecoderCommand::NONE; + } + } while (cmd == DecoderCommand::NONE); + + /* cleanup */ + + mpg123_delete(handle); +} + +static bool +mpd_mpg123_scan_file(Path path_fs, + const struct tag_handler *handler, void *handler_ctx) +{ + mpg123_handle *handle; + int error; + off_t num_samples; + + handle = mpg123_new(nullptr, &error); + if (handle == nullptr) { + FormatError(mpg123_domain, + "mpg123_new() failed: %s", + mpg123_plain_strerror(error)); + return false; + } + + AudioFormat audio_format; + if (!mpd_mpg123_open(handle, path_fs.c_str(), audio_format)) { + mpg123_delete(handle); + return false; + } + + num_samples = mpg123_length(handle); + if (num_samples <= 0) { + mpg123_delete(handle); + return false; + } + + /* ID3 tag support not yet implemented */ + + mpg123_delete(handle); + + const auto duration = + SongTime::FromScale<uint64_t>(num_samples, + audio_format.sample_rate); + + tag_handler_invoke_duration(handler, handler_ctx, duration); + return true; +} + +static const char *const mpg123_suffixes[] = { + "mp3", + nullptr +}; + +const struct DecoderPlugin mpg123_decoder_plugin = { + "mpg123", + mpd_mpg123_init, + mpd_mpg123_finish, + /* streaming not yet implemented */ + nullptr, + mpd_mpg123_file_decode, + mpd_mpg123_scan_file, + nullptr, + nullptr, + mpg123_suffixes, + nullptr, +}; |