From f5315113a5932a44b219c872fec589ded9d3e991 Mon Sep 17 00:00:00 2001 From: "Ahmed S. Darwish" Date: Tue, 22 Nov 2016 22:16:10 +0200 Subject: [PATCH] pacat: Synchronize STDIN and "write stream ready" events Users reported pacat crashes when playing certain multi-channel audio. For example: pacat --channels=2 /dev/zero works pacat --channels=3 /dev/zero pa_stream_write() failed: EINVAL pacat --channels=4 /dev/zero works pacat --channels=5 /dev/zero pa_stream_write() failed: EINVAL pacat audio playback is pipe-like, from STDIN to PA write stream. Meanwhile STDIN "ready to read" events got regularly triggered before the write stream was even created, or at moments where the stream could not accept any more audio. In these out-of-sync cases, the write stream could not report the appropriate buffer lengths it accepts, thus a default of 4K bytes was chosen -- compatible by luck with some channel counts and incompatible with others. Instead of choosing a faulty default in these scenarios, mute the the STDIN events until the write stream is available & queriable. BugLink: https://bugs.freedesktop.org/show_bug.cgi?id=98475 Reported-by: Tanu Kaskinen Signed-off-by: Ahmed S. Darwish --- src/utils/pacat.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/src/utils/pacat.c b/src/utils/pacat.c index 2ded613b2..68362ecea 100644 --- a/src/utils/pacat.c +++ b/src/utils/pacat.c @@ -542,19 +542,20 @@ fail: static void stdin_callback(pa_mainloop_api*a, pa_io_event *e, int fd, pa_io_event_flags_t f, void *userdata) { size_t l, w = 0; ssize_t r; + bool stream_not_ready; pa_assert(a == mainloop_api); pa_assert(e); pa_assert(stdio_event == e); - if (buffer) { + stream_not_ready = !stream || pa_stream_get_state(stream) != PA_STREAM_READY || + !(l = w = pa_stream_writable_size(stream)); + + if (buffer || stream_not_ready) { mainloop_api->io_enable(stdio_event, PA_IO_EVENT_NULL); return; } - if (!stream || pa_stream_get_state(stream) != PA_STREAM_READY || !(l = w = pa_stream_writable_size(stream))) - l = 4096; - buffer = pa_xmalloc(l); if ((r = pa_read(fd, buffer, l, userdata)) <= 0) {