mia/Aegisub
1
0
Fork 1
Code Issues Pull requests Projects Releases Wiki Activity

Use std::thread rather than pthreads for AlsaPlayer

Browse source
This commit is contained in:
Thomas Goyne 2014-05-22 20:13:08 -07:00
parent c2b8892b33
commit 1bf6197869
1 changed files with 112 additions and 223 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

335
src/audio_player_alsa.cpp
View file

@ -44,128 +44,74 @@
#include <libaegisub/log.h>
#include <libaegisub/make_unique.h>
#include <atomic>
#include <algorithm>
#include <boost/scope_exit.hpp>
#include <chrono>
#include <condition_variable>
#include <alsa/asoundlib.h>
#include <inttypes.h>
#include <memory>
#include <mutex>
#include <thread>
// X11 is the bestest
#undef None
namespace {
struct PlaybackState {
pthread_mutex_t mutex;
pthread_cond_t cond;
bool playing = false;
bool alive = false;
bool signal_start = false;
bool signal_stop = false;
bool signal_close = false;
bool signal_volume = false;
double volume = 1.0;
int64_t start_position = 0;
int64_t end_position = 0;
AudioProvider *provider = nullptr;
std::string device_name;
int64_t last_position = 0;
timespec last_position_time;
PlaybackState()
{
pthread_mutex_init(&mutex, 0);
pthread_cond_init(&cond, 0);
memset(&last_position_time, 0, sizeof last_position_time);
}
~PlaybackState()
{
pthread_cond_destroy(&cond);
pthread_mutex_destroy(&mutex);
}
enum class Message {
None,
Start,
Stop,
Close
};
class AlsaPlayer final : public AudioPlayer {
PlaybackState ps;
pthread_t thread;
std::mutex mutex;
std::condition_variable cond;
std::string device_name = OPT_GET("Player/Audio/ALSA/Device")->GetString();
Message message = Message::None;
std::atomic<bool> playing{false};
std::atomic<double> volume{1.0};
int64_t start_position = 0;
std::atomic<int64_t> end_position{0};
int64_t last_position = 0;
timespec last_position_time = {0, 0};
std::thread thread;
void PlaybackThread();
public:
AlsaPlayer(AudioProvider *provider);
~AlsaPlayer();
void Play(int64_t start, int64_t count);
void Stop();
bool IsPlaying();
void Play(int64_t start, int64_t count) override;
void Stop() override;
bool IsPlaying() override { return playing; }
int64_t GetStartPosition();
int64_t GetEndPosition();
int64_t GetCurrentPosition();
void SetEndPosition(int64_t pos);
void SetCurrentPosition(int64_t pos);
void SetVolume(double vol);
void SetVolume(double vol) override { volume = vol; }
int64_t GetEndPosition() override { return end_position; }
int64_t GetCurrentPosition() override;
void SetEndPosition(int64_t pos) override;
};
class PthreadMutexLocker {
pthread_mutex_t &mutex;
PthreadMutexLocker(const PthreadMutexLocker &) = delete;
PthreadMutexLocker& operator=(PthreadMutexLocker const&) = delete;
public:
explicit PthreadMutexLocker(pthread_mutex_t &mutex) : mutex(mutex)
{
pthread_mutex_lock(&mutex);
}
~PthreadMutexLocker()
{
pthread_mutex_unlock(&mutex);
}
int WaitCondition(pthread_cond_t &cond)
{
return pthread_cond_wait(&cond, &mutex);
}
int WaitConditionTimeout(pthread_cond_t &cond, int ms)
{
timespec abstime;
clock_gettime(CLOCK_REALTIME, &abstime);
abstime.tv_nsec += ms * 1000000;
return pthread_cond_timedwait(&cond, &mutex, &abstime);
}
};
class ScopedAliveFlag {
bool &flag;
ScopedAliveFlag(const ScopedAliveFlag &) = delete;
ScopedAliveFlag& operator=(ScopedAliveFlag const&) = delete;
public:
explicit ScopedAliveFlag(bool &var) : flag(var) { flag = true; }
~ScopedAliveFlag() { flag = false; }
};
void *playback_thread(void *arg)
void AlsaPlayer::PlaybackThread()
{
// This is exception-free territory!
// Return a pointer to a static string constant describing the error, or 0 on no error
auto &ps = *static_cast<PlaybackState *>(arg);
std::unique_lock<std::mutex> lock(mutex);
PthreadMutexLocker ml(ps.mutex);
ScopedAliveFlag alive_flag(ps.alive);
snd_pcm_t *pcm = 0;
if (snd_pcm_open(&pcm, ps.device_name.c_str(), SND_PCM_STREAM_PLAYBACK, 0) != 0)
return (void*)"snd_pcm_open";
snd_pcm_t *pcm = nullptr;
if (snd_pcm_open(&pcm, device_name.c_str(), SND_PCM_STREAM_PLAYBACK, 0) != 0)
return;
LOG_D("audio/player/alsa") << "opened pcm";
BOOST_SCOPE_EXIT_ALL(&) { snd_pcm_close(pcm); };
do_setup:
snd_pcm_format_t pcm_format;
switch (ps.provider->GetBytesPerSample())
switch (provider->GetBytesPerSample())
{
case 1:
LOG_D("audio/player/alsa") << "format U8";
@ -176,62 +122,58 @@ do_setup:
pcm_format = SND_PCM_FORMAT_S16_LE;
break;
default:
snd_pcm_close(pcm);
return (void*)"snd_pcm_format_t";
return;
}
if (snd_pcm_set_params(pcm,
pcm_format,
SND_PCM_ACCESS_RW_INTERLEAVED,
ps.provider->GetChannels(),
ps.provider->GetSampleRate(),
provider->GetChannels(),
provider->GetSampleRate(),
1, // allow resample
100*1000 // 100 milliseconds latency
) != 0)
return (void*)"snd_pcm_set_params";
return;
LOG_D("audio/player/alsa") << "set pcm params";
size_t framesize = ps.provider->GetChannels() * ps.provider->GetBytesPerSample();
size_t framesize = provider->GetChannels() * provider->GetBytesPerSample();
ps.signal_close = false;
while (ps.signal_close == false)
while (true)
{
// Wait for condition to trigger
if (!ps.signal_start)
ml.WaitCondition(ps.cond);
LOG_D("audio/player/alsa") << "outer loop, condition happened";
if (ps.signal_start == false || ps.end_position <= ps.start_position)
while (message != Message::Start)
{
LOG_D("audio/player/alsa") << "nothing to play, rewaiting";
ps.signal_start = false;
continue;
cond.wait(lock, [&] { return message != Message::None; });
if (message == Message::Close)
return;
if (message == Message::Start && end_position > start_position)
break;
// Not playing, so don't need to stop...
message = Message::None;
}
message = Message::None;
LOG_D("audio/player/alsa") << "starting playback";
int64_t position = ps.start_position;
int64_t position = start_position;
// Playback position
ps.last_position = position;
clock_gettime(CLOCK_REALTIME, &ps.last_position_time);
last_position = position;
clock_gettime(CLOCK_REALTIME, &last_position_time);
// Initial buffer-fill
{
snd_pcm_sframes_t avail = std::min(snd_pcm_avail(pcm), (snd_pcm_sframes_t)(ps.end_position-position));
auto avail = std::min(snd_pcm_avail(pcm), (snd_pcm_sframes_t)(end_position-position));
std::unique_ptr<char[]> buf{new char[avail*framesize]};
ps.provider->GetAudioWithVolume(buf.get(), position, avail, ps.volume);
provider->GetAudioWithVolume(buf.get(), position, avail, volume);
snd_pcm_sframes_t written = 0;
while (written <= 0)
{
written = snd_pcm_writei(pcm, buf.get(), avail);
if (written == -ESTRPIPE)
{
snd_pcm_recover(pcm, written, 0);
}
else if (written <= 0)
{
snd_pcm_close(pcm);
LOG_D("audio/player/alsa") << "error filling buffer";
return (void*)"snd_pcm_writei";
return;
}
}
position += written;
@ -241,22 +183,21 @@ do_setup:
LOG_D("audio/player/alsa") << "initial buffer filled, hitting start";
snd_pcm_start(pcm);
ps.signal_start = false;
ps.signal_stop = false;
while (ps.signal_stop == false)
playing = true;
BOOST_SCOPE_EXIT_ALL(&) { playing = false; };
while (true)
{
int64_t orig_position = position;
int64_t orig_ps_end_position = ps.end_position;
ScopedAliveFlag playing_flag(ps.playing);
// Sleep a bit, or until an event
ml.WaitConditionTimeout(ps.cond, 50);
//LOG_D("audio/player/alsa") << "playback loop, out of wait";
cond.wait_for(lock, std::chrono::milliseconds{25});
if (message == Message::Close)
{
snd_pcm_drop(pcm);
return;
}
// Check for stop signal
if (ps.signal_stop == true)
if (message == Message::Stop || message == Message::Start)
{
LOG_D("audio/player/alsa") << "playback loop, stop signal";
snd_pcm_drop(pcm);
@ -267,8 +208,8 @@ do_setup:
snd_pcm_sframes_t delay;
if (snd_pcm_delay(pcm, &delay) == 0)
{
ps.last_position = position - delay;
clock_gettime(CLOCK_REALTIME, &ps.last_position_time);
last_position = position - delay;
clock_gettime(CLOCK_REALTIME, &last_position_time);
}
// Fill buffer
@ -278,66 +219,50 @@ do_setup:
if (snd_pcm_recover(pcm, -EPIPE, 1) < 0)
{
LOG_D("audio/player/alsa") << "failed to recover from underrun";
return (void*)"snd_pcm_avail";
return;
}
tmp_pcm_avail = snd_pcm_avail(pcm);
}
avail = std::min(tmp_pcm_avail, (snd_pcm_sframes_t)(ps.end_position-position));
auto avail = std::min(tmp_pcm_avail, (snd_pcm_sframes_t)(end_position-position));
if (avail < 0)
{
printf("\n--------- avail was less than 0: %ld\n", (long)avail);
printf("snd_pcm_avail(pcm): %ld\n", (long)tmp_pcm_avail);
printf("original position: %" PRId64 "\n", orig_position);
printf("current position: %" PRId64 "\n", position);
printf("original ps.end_position: %" PRId64 "\n", orig_ps_end_position);
printf("current ps.end_position: %" PRId64 "\n", ps.end_position);
printf("---------\n\n");
continue;
}
{
std::unique_ptr<char[]> buf{new char[avail*framesize]};
ps.provider->GetAudioWithVolume(buf.get(), position, avail, ps.volume);
provider->GetAudioWithVolume(buf.get(), position, avail, volume);
snd_pcm_sframes_t written = 0;
while (written <= 0)
{
written = snd_pcm_writei(pcm, buf.get(), avail);
if (written == -ESTRPIPE || written == -EPIPE)
{
snd_pcm_recover(pcm, written, 0);
}
else if (written == 0)
{
break;
}
else if (written < 0)
{
snd_pcm_close(pcm);
LOG_D("audio/player/alsa") << "error filling buffer, written=" << written;
return (void*)"snd_pcm_writei";
return;
}
}
position += written;
}
//LOG_D("audio/player/alsa") << "playback loop, filled buffer";
// Check for end of playback
if (position >= ps.end_position)
if (position >= end_position)
{
LOG_D("audio/player/alsa") << "playback loop, past end, draining";
snd_pcm_drain(pcm);
break;
}
}
ps.signal_stop = false;
playing = false;
LOG_D("audio/player/alsa") << "out of playback loop";
switch (snd_pcm_state(pcm))
{
case SND_PCM_STATE_OPEN:
// no clue what could have happened here, but start over
ps.signal_start = false;
ps.signal_stop = false;
goto do_setup;
case SND_PCM_STATE_SETUP:
@ -347,80 +272,55 @@ do_setup:
case SND_PCM_STATE_DISCONNECTED:
// lost device, close the handle and return error
snd_pcm_close(pcm);
return (void*)"SND_PCM_STATE_DISCONNECTED";
return;
default:
// everything else should either be fine or impossible (here)
break;
}
}
ps.signal_close = false;
LOG_D("audio/player/alsa") << "out of outer loop";
snd_pcm_close(pcm);
return 0;
}
AlsaPlayer::AlsaPlayer(AudioProvider *provider)
AlsaPlayer::AlsaPlayer(AudioProvider *provider) try
: AudioPlayer(provider)
, thread(&AlsaPlayer::PlaybackThread, this)
{
ps.provider = provider;
ps.device_name = OPT_GET("Player/Audio/ALSA/Device")->GetString();
if (pthread_create(&thread, 0, &playback_thread, &ps) != 0)
throw agi::AudioPlayerOpenError("AlsaPlayer: Creating the playback thread failed", 0);
}
catch (std::system_error const&) {
throw agi::AudioPlayerOpenError("AlsaPlayer: Creating the playback thread failed", 0);
}
AlsaPlayer::~AlsaPlayer()
{
{
PthreadMutexLocker ml(ps.mutex);
ps.signal_stop = true;
ps.signal_close = true;
LOG_D("audio/player/alsa") << "close stream, stop+close signal";
pthread_cond_signal(&ps.cond);
std::unique_lock<std::mutex> lock(mutex);
message = Message::Close;
cond.notify_all();
}
pthread_join(thread, 0); // FIXME: check for errors
thread.join();
}
void AlsaPlayer::Play(int64_t start, int64_t count)
{
PthreadMutexLocker ml(ps.mutex);
ps.signal_start = true;
ps.signal_stop = true; // make sure to stop any ongoing playback first
ps.start_position = start;
ps.end_position = start + count;
pthread_cond_signal(&ps.cond);
std::unique_lock<std::mutex> lock(mutex);
message = Message::Start;
start_position = start;
end_position = start + count;
cond.notify_all();
}
void AlsaPlayer::Stop()
{
PthreadMutexLocker ml(ps.mutex);
ps.signal_stop = true;
LOG_D("audio/player/alsa") << "stop stream, stop signal";
pthread_cond_signal(&ps.cond);
}
bool AlsaPlayer::IsPlaying()
{
PthreadMutexLocker ml(ps.mutex);
return ps.playing;
std::unique_lock<std::mutex> lock(mutex);
message = Message::Stop;
cond.notify_all();
}
void AlsaPlayer::SetEndPosition(int64_t pos)
{
PthreadMutexLocker ml(ps.mutex);
ps.end_position = pos;
}
int64_t AlsaPlayer::GetEndPosition()
{
PthreadMutexLocker ml(ps.mutex);
return ps.end_position;
std::unique_lock<std::mutex> lock(mutex);
end_position = pos;
}
int64_t AlsaPlayer::GetCurrentPosition()
@ -430,10 +330,10 @@ int64_t AlsaPlayer::GetCurrentPosition()
int64_t samplerate;
{
PthreadMutexLocker ml(ps.mutex);
lastpos = ps.last_position;
lasttime = ps.last_position_time;
samplerate = ps.provider->GetSampleRate();
std::unique_lock<std::mutex> lock(mutex);
lastpos = last_position;
lasttime = last_position_time;
samplerate = provider->GetSampleRate();
}
timespec now;
@ -445,18 +345,7 @@ int64_t AlsaPlayer::GetCurrentPosition()
double last_sec = lasttime.tv_sec + lasttime.tv_nsec/NANO;
double diff_sec = now_sec - last_sec;
int64_t pos = lastpos + (int64_t)(diff_sec * samplerate);
//printf("AlsaPlayer: current position = %lld\n", pos);
return pos;
}
void AlsaPlayer::SetVolume(double vol)
{
PthreadMutexLocker ml(ps.mutex);
ps.volume = vol;
ps.signal_volume = true;
pthread_cond_signal(&ps.cond);
return lastpos + (int64_t)(diff_sec * samplerate);
}
}