Bug 761274 - Work around buffer sizing bug in PulseAudio ALSA plugin. r=doublec

content/media/nsAudioStream.cpp

@@ -880,13 +880,13 @@ private:
     return static_cast<nsBufferedAudioStream*>(aThis)->DataCallback(aBuffer, aFrames);
   }
 
-  static int StateCallback_S(cubeb_stream*, void* aThis, cubeb_state aState)
+  static void StateCallback_S(cubeb_stream*, void* aThis, cubeb_state aState)
   {
-    return static_cast<nsBufferedAudioStream*>(aThis)->StateCallback(aState);
+    static_cast<nsBufferedAudioStream*>(aThis)->StateCallback(aState);
   }
 
   long DataCallback(void* aBuffer, long aFrames);
-  int StateCallback(cubeb_state aState);
+  void StateCallback(cubeb_state aState);
 
   // Shared implementation of underflow adjusted position calculation.
   // Caller must own the monitor.
@@ -1268,7 +1268,7 @@ nsBufferedAudioStream::DataCallback(void* aBuffer, long aFrames)
   return aFrames - (bytesWanted / mBytesPerFrame);
 }
 
-int
+void
 nsBufferedAudioStream::StateCallback(cubeb_state aState)
 {
   MonitorAutoLock mon(mMonitor);
@@ -1278,7 +1278,6 @@ nsBufferedAudioStream::StateCallback(cubeb_state aState)
     mState = ERRORED;
   }
   mon.NotifyAll();
-  return CUBEB_OK;
 }
 #endif
 

media/libcubeb/AUTHORS

@@ -1 +1,2 @@
 Matthew Gregan <kinetik@flim.org>
+Alexandre Ratchov <alex@caoua.org>

media/libcubeb/README_MOZILLA

@@ -5,4 +5,4 @@ Makefile.in build files for the Mozilla build system.
 
 The cubeb git repository is: git://github.com/kinetiknz/cubeb.git
 
-The git commit ID used was 21d9678eb9755761f7a9d26253189b926258de7c.
+The git commit ID used was f3116936eba69aced240df7db77264269f3f95ae.

media/libcubeb/include/cubeb.h

@@ -40,8 +40,8 @@ extern "C" {
 
     cubeb_stream_start(stm);
     for (;;) {
-      cubeb_get_time(stm, &ts);
-      printf("time=%lu\n", ts);
+      cubeb_stream_get_position(stm, &ts);
+      printf("time=%llu\n", ts);
       sleep(1);
     }
     cubeb_stream_stop(stm);
@@ -64,10 +64,9 @@ extern "C" {
     @endcode
 
     @code
-    int state_cb(cubeb_stream * stm, void * user, cubeb_state state)
+    void state_cb(cubeb_stream * stm, void * user, cubeb_state state)
     {
       printf("state=%d\n", state);
-      return CUBEB_OK;
     }
     @endcode
 */
@@ -141,12 +140,10 @@ typedef long (* cubeb_data_callback)(cubeb_stream * stream,
 /** User supplied state callback.
     @param stream
     @param user_ptr
-    @param state
-    @retval CUBEB_OK
-    @retval CUBEB_ERROR */
-typedef int (* cubeb_state_callback)(cubeb_stream * stream,
-                                     void * user_ptr,
-                                     cubeb_state state);
+    @param state */
+typedef void (* cubeb_state_callback)(cubeb_stream * stream,
+                                      void * user_ptr,
+                                      cubeb_state state);
 
 /** Initialize an application context.  This will perform any library or
     application scoped initialization.
@@ -156,6 +153,11 @@ typedef int (* cubeb_state_callback)(cubeb_stream * stream,
     @retval CUBEB_ERROR */
 int cubeb_init(cubeb ** context, char const * context_name);
 
+/** Get a read-only string identifying this context's current backend.
+    @param context
+    @retval Read-only string identifying current backend. */
+char const * cubeb_get_backend_id(cubeb * context);
+
 /** Destroy an application context.
     @param context */
 void cubeb_destroy(cubeb * context);

media/libcubeb/src/cubeb_alsa.c

@@ -20,6 +20,8 @@
 #define CUBEB_WATCHDOG_MS 10000
 #define UNUSED __attribute__ ((__unused__))
 
+#define ALSA_PA_PLUGIN "ALSA <-> PulseAudio PCM I/O Plugin"
+
 /* ALSA is not thread-safe.  snd_pcm_t instances are individually protected
    by the owning cubeb_stream's mutex.  snd_pcm_t creation and destruction
    is not thread-safe until ALSA 1.0.24 (see alsa-lib.git commit 91c9c8f1),
@@ -474,6 +476,24 @@ silent_error_handler(char const * file UNUSED, int line UNUSED, char const * fun
 {
 }
 
+static int
+pcm_uses_pulseaudio_plugin(snd_pcm_t * pcm)
+{
+  snd_output_t * out;
+  char * buf;
+  size_t bufsz;
+  int r;
+
+  snd_output_buffer_open(&out);
+  snd_pcm_dump(pcm, out);
+  bufsz = snd_output_buffer_string(out, &buf);
+  r = bufsz >= strlen(ALSA_PA_PLUGIN) &&
+      strncmp(buf, ALSA_PA_PLUGIN, strlen(ALSA_PA_PLUGIN)) == 0;
+  snd_output_close(out);
+
+  return r;
+}
+
 int
 cubeb_init(cubeb ** context, char const * context_name UNUSED)
 {
@@ -531,6 +551,12 @@ cubeb_init(cubeb ** context, char const * context_name UNUSED)
   return CUBEB_OK;
 }
 
+char const *
+cubeb_get_backend_id(cubeb * ctx UNUSED)
+{
+  return "alsa";
+}
+
 void
 cubeb_destroy(cubeb * ctx)
 {
@@ -621,6 +647,12 @@ cubeb_stream_init(cubeb * ctx, cubeb_stream ** stream, char const * stream_name
   r = snd_pcm_nonblock(stm->pcm, 1);
   assert(r == 0);
 
+  /* Ugly hack: the PA ALSA plugin allows buffer configurations that can't
+     possibly work.  See https://bugzilla.mozilla.org/show_bug.cgi?id=761274 */
+  if (pcm_uses_pulseaudio_plugin(stm->pcm)) {
+    latency = latency < 200 ? 200 : latency;
+  }
+
   r = snd_pcm_set_params(stm->pcm, format, SND_PCM_ACCESS_RW_INTERLEAVED,
                          stm->params.channels, stm->params.rate, 1,
                          latency * 1000);

media/libcubeb/src/cubeb_audiounit.c

@@ -87,6 +87,12 @@ cubeb_init(cubeb ** context, char const * context_name)
   return CUBEB_OK;
 }
 
+char const *
+cubeb_get_backend_id(cubeb * ctx)
+{
+  return "audiounit";
+}
+
 void
 cubeb_destroy(cubeb * ctx)
 {

media/libcubeb/src/cubeb_pulse.c

@@ -116,9 +116,9 @@ stream_request_callback(pa_stream * s, size_t nbytes, void * u)
 
     if ((size_t) got < size / frame_size) {
       size_t buffer_fill = pa_stream_get_buffer_attr(s)->maxlength - pa_stream_writable_size(s);
-      double buffer_time = (double) buffer_fill / stm->sample_spec.rate;
+      pa_usec_t buffer_time = pa_bytes_to_usec(buffer_fill, &stm->sample_spec);
       /* pa_stream_drain is useless, see PA bug# 866. this is a workaround. */
-      stm->drain_timer = pa_context_rttime_new(stm->context->context, pa_rtclock_now() + buffer_time * 1e6, stream_drain_callback, stm);
+      stm->drain_timer = pa_context_rttime_new(stm->context->context, pa_rtclock_now() + buffer_time, stream_drain_callback, stm);
       stm->shutdown = 1;
       return;
     }
@@ -211,6 +211,12 @@ cubeb_init(cubeb ** context, char const * context_name)
   return CUBEB_OK;
 }
 
+char const *
+cubeb_get_backend_id(cubeb * ctx)
+{
+  return "pulse";
+}
+
 void
 cubeb_destroy(cubeb * ctx)
 {
@@ -295,7 +301,7 @@ cubeb_stream_init(cubeb * context, cubeb_stream ** stream, char const * stream_n
   battr.maxlength = -1;
   battr.tlength = pa_usec_to_bytes(latency * PA_USEC_PER_MSEC, &stm->sample_spec);
   battr.prebuf = -1;
-  battr.minreq = battr.tlength / 2;
+  battr.minreq = battr.tlength / 4;
   battr.fragsize = -1;
 
   pa_threaded_mainloop_lock(stm->context->mainloop);

media/libcubeb/src/cubeb_winmm.c

@@ -1,5 +1,5 @@
 /*
- * Copyright <EFBFBD>Â<EFBFBD>© 2011 Mozilla Foundation
+ * Copyright © 2011 Mozilla Foundation
  *
  * This program is made available under an ISC-style license.  See the
  * accompanying file LICENSE for details.
@@ -123,6 +123,7 @@ cubeb_refill_stream(cubeb_stream * stm)
   got = stm->data_callback(stm, stm->user_ptr, hdr->lpData, wanted);
   EnterCriticalSection(&stm->lock);
   if (got < 0) {
+    LeaveCriticalSection(&stm->lock);
     /* XXX handle this case */
     assert(0);
     return;
@@ -226,6 +227,12 @@ cubeb_init(cubeb ** context, char const * context_name)
   return CUBEB_OK;
 }
 
+char const *
+cubeb_get_backend_id(cubeb * ctx)
+{
+  return "winmm";
+}
+
 void
 cubeb_destroy(cubeb * ctx)
 {