Once again get rid of busy waiting and use SIGSTOP for pause

The problems I had were related to the OSS driver and USB
device I was using.  The problems existed even with the old
busy-waiting scheme enabled.

OSS  - Bithead USB     => bad
ALSA - Bithead USB     => OK
OSS  - Onboard i8x0    => OK
ALSA - Onboard i8x0    => OK

bad - slow shutdown, pauses, dropped audio after pause/resume

git-svn-id: https://svn.musicpd.org/mpd/trunk@6861 09075e82-0dd4-0310-85a5-a0d7c8717e4f

2 files changed, 24 insertions, 4 deletions

diff --git a/src/decode.c b/src/decode.c
index c66d67fe0..bf3e1cb25 100644
--- a/src/decode.c
+++ b/src/decode.c
@@ -71,6 +71,7 @@ static void stopDecode(DecoderControl * dc)
 {
 	if (decode_pid > 0 && (dc->start || dc->state != DECODE_STATE_STOP)) {
 		dc->stop = 1;
+		kill(decode_pid, SIGCONT);
 		while (decode_pid > 0 && dc->stop)
 			my_usleep(10000);
 	}
@@ -126,7 +127,8 @@ static int calculateCrossFadeChunks(PlayerControl * pc, AudioFormat * af)
 				ERROR("problems opening audio device while playing \"%s\"\n", pc->utf8url); \
 				quitDecode(pc,dc); \
 				return; \
-			} \
+			} else if (decode_pid > 0) { \
+				kill(decode_pid, SIGCONT); }\
 			if (pause) { \
 				dropBufferedAudio(); \
 				closeAudioDevice(); \
@@ -238,6 +240,8 @@ static int decodeSeek(PlayerControl * pc, DecoderControl * dc,
 			pc->state = PLAYER_STATE_PAUSE; \
 		} else { \
 			if (openAudioDevice(NULL) >= 0) { \
+				if (decode_pid > 0) \
+					kill(decode_pid, SIGCONT); \
 				pc->state = PLAYER_STATE_PLAY; \
 			} else { \
 				pathcpy_trunc(pc->erroredUrl, pc->utf8url); \
@@ -579,9 +583,11 @@ static void decodeParent(PlayerControl * pc, DecoderControl * dc, OutputBuffer *
 		   race conditions and weirdness */
 		end = cb->end;
 
-		if (pause)
-			my_usleep(10000);
-		else if (cb->begin != end && cb->begin != next) {
+		if (pause) {
+			if (decode_pid)
+				kill(decode_pid, SIGSTOP);
+			kill(getpid(), SIGSTOP);
+		} else if (cb->begin != end && cb->begin != next) {
 			if (doCrossFade == 1 && next >= 0 &&
 			    ((next > cb->begin &&
 			      (fadePosition = next - cb->begin)
diff --git a/src/player.c b/src/player.c
index c53a6ae1d..d73b0a0e1 100644
--- a/src/player.c
+++ b/src/player.c
@@ -231,6 +231,8 @@ int playerPlay(int fd, Song * song)
 	}
 
 	resetPlayerMetadata();
+	if (player_pid > 0 && pc->state == PLAYER_STATE_PAUSE)
+		kill(player_pid, SIGCONT);
 	while (player_pid > 0 && pc->play)
 		my_usleep(1000);
 
@@ -243,6 +245,8 @@ int playerStop(int fd)
 
 	if (player_pid > 0 && pc->state != PLAYER_STATE_STOP) {
 		pc->stop = 1;
+		if (pc->state == PLAYER_STATE_PAUSE)
+			kill(player_pid, SIGCONT);
 		while (player_pid > 0 && pc->stop)
 			my_usleep(1000);
 	}
@@ -270,6 +274,8 @@ int playerPause(int fd)
 
 	if (player_pid > 0 && pc->state != PLAYER_STATE_STOP) {
 		pc->pause = 1;
+		if (player_pid > 0 && pc->state == PLAYER_STATE_PAUSE)
+			kill(player_pid, SIGCONT);
 		while (player_pid > 0 && pc->pause)
 			my_usleep(1000);
 	}
@@ -377,6 +383,8 @@ void playerCloseAudio(void)
 		if (playerStop(STDERR_FILENO) < 0)
 			return;
 		pc->closeAudio = 1;
+		if (pc->state == PLAYER_STATE_PAUSE)
+			kill(player_pid, SIGCONT);
 		while (player_pid > 0 && pc->closeAudio)
 			my_usleep(1000);
 	}
@@ -422,6 +430,8 @@ void playerQueueLock(void)
 	PlayerControl *pc = &(getPlayerData()->playerControl);
 
 	if (player_pid > 0 && pc->queueLockState == PLAYER_QUEUE_UNLOCKED) {
+		if (pc->state == PLAYER_STATE_PAUSE)
+			kill(player_pid, SIGCONT);
 		pc->lockQueue = 1;
 		while (player_pid > 0 && pc->lockQueue)
 			my_usleep(1000);
@@ -433,6 +443,8 @@ void playerQueueUnlock(void)
 	PlayerControl *pc = &(getPlayerData()->playerControl);
 
 	if (player_pid > 0 && pc->queueLockState == PLAYER_QUEUE_LOCKED) {
+		if (pc->state == PLAYER_STATE_PAUSE)
+			kill(player_pid, SIGCONT);
 		pc->unlockQueue = 1;
 		while (player_pid > 0 && pc->unlockQueue)
 			my_usleep(1000);
@@ -464,6 +476,8 @@ int playerSeek(int fd, Song * song, float time)
 		resetPlayerMetadata();
 		pc->seekWhere = time;
 		pc->seek = 1;
+		if (player_pid > 0 && pc->state == PLAYER_STATE_PAUSE)
+			kill(player_pid, SIGCONT);
 		while (player_pid > 0 && pc->seek)
 			my_usleep(1000);
 	}