From 21f66868d24e97930f826fb9970a9d1e4b144cf9 Mon Sep 17 00:00:00 2001 From: Kevin Ross Date: Thu, 4 Aug 2011 16:19:56 +0200 Subject: [PATCH] jack: Fix hanging applications when using jack plugin As described in issue #2727 https://bugtrack.alsa-project.org/alsa-bug/view.php?id=2727 applications hang after some seconds when using the jack plugin. Kevin Ross writes: The cause: The plugin creates a pipe, so that the fd's could be polled to indicate completion of a transfer. However, the call to write() blocks when playing audio, as nothing actually reads from the pipe, and it fills up until it blocks. Making the socket non-blocking fixes the problem, and testing with playback and capture both work properly for me now. [Adrian: I've also tested Kevin's patch and confirm it works.] Signed-off-by: Adrian Knoth Signed-off-by: Takashi Iwai --- jack/pcm_jack.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/jack/pcm_jack.c b/jack/pcm_jack.c index 3370a26..eb3359c 100644 --- a/jack/pcm_jack.c +++ b/jack/pcm_jack.c @@ -307,6 +307,19 @@ static int parse_ports(snd_pcm_jack_t *jack, snd_config_t *conf) return 0; } +static int make_nonblock(int fd) +{ + int fl; + + if ((fl = fcntl(fd, F_GETFL)) < 0) + return fl; + + if (fl & O_NONBLOCK) + return 0; + + return fcntl(fd, F_SETFL, fl | O_NONBLOCK); +} + static int snd_pcm_jack_open(snd_pcm_t **pcmp, const char *name, snd_config_t *playback_conf, snd_config_t *capture_conf, @@ -363,6 +376,9 @@ static int snd_pcm_jack_open(snd_pcm_t **pcmp, const char *name, socketpair(AF_LOCAL, SOCK_STREAM, 0, fd); + make_nonblock(fd[0]); + make_nonblock(fd[1]); + jack->fd = fd[0]; jack->io.version = SND_PCM_IOPLUG_VERSION; -- 2.47.3