Avoid freeing an in-use capture buffer

When stopping, ALSA may capture into its own storage buffer. Do not free
the storage buffer if it first reads from it.

1 files changed, 3 insertions, 5 deletions

diff --git a/Alc/backends/alsa.c b/Alc/backends/alsa.c
index 749db892..d0677068 100644
--- a/Alc/backends/alsa.c
+++ b/Alc/backends/alsa.c
@@ -1167,16 +1167,14 @@ static ALCenum ALCcaptureAlsa_captureSamples(ALCcaptureAlsa *self, ALCvoid *buff
             memmove(buffer, self->buffer, amt);
 
             if(self->size > amt)
-            {
                 memmove(self->buffer, self->buffer+amt, self->size - amt);
-                self->size -= amt;
-            }
-            else
+            else if(self->buffer != buffer)
             {
+                /* Do not free the buffer if it's reading into itself. */
                 free(self->buffer);
                 self->buffer = NULL;
-                self->size = 0;
             }
+            self->size -= amt;
             amt = snd_pcm_bytes_to_frames(self->pcmHandle, amt);
         }
         else if(self->doCapture)