From 3d5a78e67a70194f3724b0d0c4f213681283eecf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tim-Philipp=20M=C3=BCller?= <tim@centricular.net>
Date: Sat, 15 Dec 2012 19:36:56 +0000
Subject: [PATCH] alsa: post error message when audio device disappears

Don't loop forever if an USB audio device gets disconnected
while in use. Post an error message instead. This is not
enough yet though, we still need to make the base class
and/or the ring buffer bail out.

https://bugzilla.gnome.org/show_bug.cgi?id=690197
---
 ext/alsa/gstalsasink.c | 11 ++++++++++-
 ext/alsa/gstalsasrc.c  | 11 ++++++++++-
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/ext/alsa/gstalsasink.c b/ext/alsa/gstalsasink.c
index 27a8bd88b7..1ef6b91f74 100644
--- a/ext/alsa/gstalsasink.c
+++ b/ext/alsa/gstalsasink.c
@@ -955,7 +955,7 @@ gst_alsasink_close (GstAudioSink * asink)
 static gint
 xrun_recovery (GstAlsaSink * alsa, snd_pcm_t * handle, gint err)
 {
-  GST_DEBUG_OBJECT (alsa, "xrun recovery %d", err);
+  GST_DEBUG_OBJECT (alsa, "xrun recovery %d: %s", err, g_strerror (err));
 
   if (err == -EPIPE) {          /* under-run */
     err = snd_pcm_prepare (handle);
@@ -1019,6 +1019,8 @@ gst_alsasink_write (GstAudioSink * asink, gpointer data, guint length)
       GST_DEBUG_OBJECT (asink, "Write error: %s", snd_strerror (err));
       if (err == -EAGAIN) {
         continue;
+      } else if (err == -ENODEV) {
+        goto device_disappeared;
       } else if (xrun_recovery (alsa, alsa->handle, err) < 0) {
         goto write_error;
       }
@@ -1037,6 +1039,13 @@ write_error:
     GST_ALSA_SINK_UNLOCK (asink);
     return length;              /* skip one period */
   }
+device_disappeared:
+  {
+    GST_ELEMENT_ERROR (asink, RESOURCE, WRITE,
+        (_("Error outputting to audio device. "
+                "The device has been disconnected.")), (NULL));
+    goto write_error;
+  }
 }
 
 static guint
diff --git a/ext/alsa/gstalsasrc.c b/ext/alsa/gstalsasrc.c
index f97da9bd6c..3b2f4bb8cc 100644
--- a/ext/alsa/gstalsasrc.c
+++ b/ext/alsa/gstalsasrc.c
@@ -805,7 +805,7 @@ gst_alsasrc_close (GstAudioSrc * asrc)
 static gint
 xrun_recovery (GstAlsaSrc * alsa, snd_pcm_t * handle, gint err)
 {
-  GST_DEBUG_OBJECT (alsa, "xrun recovery %d", err);
+  GST_DEBUG_OBJECT (alsa, "xrun recovery %d: %s", err, g_strerror (err));
 
   if (err == -EPIPE) {          /* under-run */
     err = snd_pcm_prepare (handle);
@@ -907,6 +907,8 @@ gst_alsasrc_read (GstAudioSrc * asrc, gpointer data, guint length,
       if (err == -EAGAIN) {
         GST_DEBUG_OBJECT (asrc, "Read error: %s", snd_strerror (err));
         continue;
+      } else if (err == -ENODEV) {
+        goto device_disappeared;
       } else if (xrun_recovery (alsa, alsa->handle, err) < 0) {
         goto read_error;
       }
@@ -929,6 +931,13 @@ read_error:
     GST_ALSA_SRC_UNLOCK (asrc);
     return length;              /* skip one period */
   }
+device_disappeared:
+  {
+    GST_ELEMENT_ERROR (asrc, RESOURCE, READ,
+        (_("Error recording from audio device. "
+                "The device has been disconnected.")), (NULL));
+    goto read_error;
+  }
 }
 
 static guint