From ccc88607b60e7fad7be4fc26c7a0d47aeae3fe15 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Sch=C3=BCrmann?= <daschuer@mixxx.org>
Date: Thu, 12 Nov 2020 00:25:34 +0100
Subject: [PATCH 1/4] Don't crash if alsa_snd_pcm_poll_descriptors fails

---
 src/hostapi/alsa/pa_linux_alsa.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/src/hostapi/alsa/pa_linux_alsa.c b/src/hostapi/alsa/pa_linux_alsa.c
index 5539d9d..48d77c1 100644
--- a/src/hostapi/alsa/pa_linux_alsa.c
+++ b/src/hostapi/alsa/pa_linux_alsa.c
@@ -3642,8 +3642,11 @@ static PaError PaAlsaStreamComponent_BeginPolling( PaAlsaStreamComponent* self,
     PaError result = paNoError;
     int ret = alsa_snd_pcm_poll_descriptors( self->pcm, pfds, self->nfds );
     (void)ret;  /* Prevent unused variable warning if asserts are turned off */
-    assert( ret == self->nfds );
-
+    /* If alsa returns anything else, like -EPIPE return*/
+    if( ret != self->nfds )
+    {
+      return paUnanticipatedHostError;
+    }
     self->ready = 0;
 
     return result;
@@ -3810,7 +3813,12 @@ static PaError PaAlsaStream_WaitForFrames( PaAlsaStream *self, unsigned long *fr
         {
             /* self->pfds is in effect an array of fds; if necessary, index past the capture fds */
             playbackPfds = self->pfds + (pollCapture ? self->capture.nfds : 0);
-            PA_ENSURE( PaAlsaStreamComponent_BeginPolling( &self->playback, playbackPfds ) );
+            int res = PaAlsaStreamComponent_BeginPolling( &self->playback, playbackPfds );
+            if( res != paNoError)
+            {
+              xrun = 1;
+              goto end;
+            }
             totalFds += self->playback.nfds;
         }
 

From b37657be7081c8cd4dbb16f1f592082795dce776 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Sch=C3=BCrmann?= <daschuer@mixxx.org>
Date: Fri, 27 Nov 2020 08:40:45 +0100
Subject: [PATCH 2/4] Remove superfluid void cast

---
 src/hostapi/alsa/pa_linux_alsa.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/hostapi/alsa/pa_linux_alsa.c b/src/hostapi/alsa/pa_linux_alsa.c
index 48d77c1..0564351 100644
--- a/src/hostapi/alsa/pa_linux_alsa.c
+++ b/src/hostapi/alsa/pa_linux_alsa.c
@@ -3641,7 +3641,6 @@ static PaError PaAlsaStreamComponent_BeginPolling( PaAlsaStreamComponent* self,
 {
     PaError result = paNoError;
     int ret = alsa_snd_pcm_poll_descriptors( self->pcm, pfds, self->nfds );
-    (void)ret;  /* Prevent unused variable warning if asserts are turned off */
     /* If alsa returns anything else, like -EPIPE return*/
     if( ret != self->nfds )
     {

From 8f63b5180830ad3da103597305f4504fa4935148 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Sch=C3=BCrmann?= <daschuer@mixxx.org>
Date: Mon, 14 Dec 2020 08:03:04 +0100
Subject: [PATCH 3/4] Don't crash for alsa_snd_pcm_poll_descriptors fail in
 another case

---
 src/hostapi/alsa/pa_linux_alsa.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/hostapi/alsa/pa_linux_alsa.c b/src/hostapi/alsa/pa_linux_alsa.c
index 0564351..22c30f1 100644
--- a/src/hostapi/alsa/pa_linux_alsa.c
+++ b/src/hostapi/alsa/pa_linux_alsa.c
@@ -3805,14 +3805,19 @@ static PaError PaAlsaStream_WaitForFrames( PaAlsaStream *self, unsigned long *fr
         if( pollCapture )
         {
             capturePfds = self->pfds;
-            PA_ENSURE( PaAlsaStreamComponent_BeginPolling( &self->capture, capturePfds ) );
+            PaError res = PaAlsaStreamComponent_BeginPolling( &self->capture, capturePfds );
+            if( res != paNoError)
+            {
+              xrun = 1;
+              goto end;
+            }
             totalFds += self->capture.nfds;
         }
         if( pollPlayback )
         {
             /* self->pfds is in effect an array of fds; if necessary, index past the capture fds */
             playbackPfds = self->pfds + (pollCapture ? self->capture.nfds : 0);
-            int res = PaAlsaStreamComponent_BeginPolling( &self->playback, playbackPfds );
+            PaError res = PaAlsaStreamComponent_BeginPolling( &self->playback, playbackPfds );
             if( res != paNoError)
             {
               xrun = 1;

From 9ddb047ab1028add40e9499d2b1a5f1e78e70e6a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Sch=C3=BCrmann?= <daschuer@mixxx.org>
Date: Mon, 14 Dec 2020 08:21:34 +0100
Subject: [PATCH 4/4] Improve code style

---
 src/hostapi/alsa/pa_linux_alsa.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/src/hostapi/alsa/pa_linux_alsa.c b/src/hostapi/alsa/pa_linux_alsa.c
index 22c30f1..12aee58 100644
--- a/src/hostapi/alsa/pa_linux_alsa.c
+++ b/src/hostapi/alsa/pa_linux_alsa.c
@@ -3639,16 +3639,15 @@ error:
  */
 static PaError PaAlsaStreamComponent_BeginPolling( PaAlsaStreamComponent* self, struct pollfd* pfds )
 {
-    PaError result = paNoError;
-    int ret = alsa_snd_pcm_poll_descriptors( self->pcm, pfds, self->nfds );
-    /* If alsa returns anything else, like -EPIPE return*/
-    if( ret != self->nfds )
+    int nfds = alsa_snd_pcm_poll_descriptors( self->pcm, pfds, self->nfds );
+    /* If alsa returns anything else, like -EPIPE return */
+    if( nfds != self->nfds )
     {
-      return paUnanticipatedHostError;
+        return paUnanticipatedHostError;
     }
     self->ready = 0;
 
-    return result;
+    return paNoError;
 }
 
 /** Examine results from poll().