From a2ae3341a73643578400e493927498d89526ceeb Mon Sep 17 00:00:00 2001
From: Wim Taymans <wim.taymans@gmail.com>
Date: Fri, 16 Jun 2006 11:04:21 +0000
Subject: [PATCH] ext/alsa/gstalsasink.c: If we fail to set the buffer_time and
 period_time alsa parameters, post a warning and leave a...

Original commit message from CVS:
* ext/alsa/gstalsasink.c: (set_hwparams):
If we fail to set the buffer_time and period_time alsa
parameters, post a warning and leave alsa select a
default instead of failing. Fixes #342085
---
 ChangeLog              |  7 ++++
 ext/alsa/gstalsasink.c | 78 ++++++++++++++++++++++++++++++------------
 2 files changed, 63 insertions(+), 22 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index ba5e9779f5..45dfe3ca46 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2006-06-16  Wim Taymans  <wim@fluendo.com>
+
+	* ext/alsa/gstalsasink.c: (set_hwparams):
+	If we fail to set the buffer_time and period_time alsa
+	parameters, post a warning and leave alsa select a 
+	default instead of failing. Fixes #342085
+
 2006-06-16  Tim-Philipp Müller  <tim at centricular dot net>
 
 	* docs/libs/gst-plugins-base-libs-sections.txt:
diff --git a/ext/alsa/gstalsasink.c b/ext/alsa/gstalsasink.c
index 17f5768dbf..ebdd47afd5 100644
--- a/ext/alsa/gstalsasink.c
+++ b/ext/alsa/gstalsasink.c
@@ -331,12 +331,19 @@ set_hwparams (GstAlsaSink * alsa)
   guint rrate;
   gint err, dir;
   snd_pcm_hw_params_t *params;
+  guint period_time, buffer_time;
 
   snd_pcm_hw_params_alloca (&params);
 
   GST_DEBUG_OBJECT (alsa, "Negotiating to %d channels @ %d Hz (format = %s)",
       alsa->channels, alsa->rate, snd_pcm_format_name (alsa->format));
 
+  /* start with requested values, if we cannot configure alsa for those values,
+   * we set these values to -1, which will leave the default alsa values */
+  buffer_time = alsa->buffer_time;
+  period_time = alsa->period_time;
+
+retry:
   /* choose all parameters */
   CHECK (snd_pcm_hw_params_any (alsa->handle, params), no_config);
   /* set the interleaved read/write format */
@@ -355,26 +362,67 @@ set_hwparams (GstAlsaSink * alsa)
   if (rrate != alsa->rate)
     goto rate_match;
 
-  if (alsa->buffer_time != -1) {
-    /* set the buffer time */
-    CHECK (snd_pcm_hw_params_set_buffer_time_near (alsa->handle, params,
-            &alsa->buffer_time, &dir), buffer_time);
+  /* get and dump some limits */
+  {
+    guint min, max;
+
+    snd_pcm_hw_params_get_buffer_time_min (params, &min, &dir);
+    snd_pcm_hw_params_get_buffer_time_max (params, &max, &dir);
+
+    GST_DEBUG_OBJECT (alsa, "buffer time %u, min %u, max %u",
+        alsa->buffer_time, min, max);
+
+    snd_pcm_hw_params_get_period_time_min (params, &min, &dir);
+    snd_pcm_hw_params_get_period_time_max (params, &max, &dir);
+
+    GST_DEBUG_OBJECT (alsa, "period time %u, min %u, max %u",
+        alsa->period_time, min, max);
+
+    snd_pcm_hw_params_get_periods_min (params, &min, &dir);
+    snd_pcm_hw_params_get_periods_max (params, &max, &dir);
+
+    GST_DEBUG_OBJECT (alsa, "periods min %u, max %u", min, max);
   }
-  if (alsa->period_time != -1) {
+
+  /* now try to configure the buffer time and period time, if one
+   * of those fail, we fall back to the defaults and emit a warning. */
+  if (buffer_time != -1) {
+    /* set the buffer time */
+    if ((err = snd_pcm_hw_params_set_buffer_time_near (alsa->handle, params,
+                &buffer_time, &dir)) < 0) {
+      GST_ELEMENT_WARNING (alsa, RESOURCE, SETTINGS, (NULL),
+          ("Unable to set buffer time %i for playback: %s",
+              buffer_time, snd_strerror (err)));
+      /* disable buffer_time the next round */
+      buffer_time = -1;
+      goto retry;
+    }
+  }
+  if (period_time != -1) {
     /* set the period time */
-    CHECK (snd_pcm_hw_params_set_period_time_near (alsa->handle, params,
-            &alsa->period_time, &dir), period_time);
+    if ((err = snd_pcm_hw_params_set_period_time_near (alsa->handle, params,
+                &period_time, &dir)) < 0) {
+      GST_ELEMENT_WARNING (alsa, RESOURCE, SETTINGS, (NULL),
+          ("Unable to set period time %i for playback: %s",
+              period_time, snd_strerror (err)));
+      /* disable period_time the next round */
+      period_time = -1;
+      goto retry;
+    }
   }
 
   /* write the parameters to device */
   CHECK (snd_pcm_hw_params (alsa->handle, params), set_hw_params);
 
+  /* now get the configured values */
   CHECK (snd_pcm_hw_params_get_buffer_size (params, &alsa->buffer_size),
       buffer_size);
-
   CHECK (snd_pcm_hw_params_get_period_size (params, &alsa->period_size, &dir),
       period_size);
 
+  GST_DEBUG_OBJECT (alsa, "buffer size %u, period size %u", alsa->buffer_size,
+      alsa->period_size);
+
   return 0;
 
   /* ERRORS */
@@ -427,26 +475,12 @@ rate_match:
         ("Rate doesn't match (requested %iHz, get %iHz)", alsa->rate, err));
     return -EINVAL;
   }
-buffer_time:
-  {
-    GST_ELEMENT_ERROR (alsa, RESOURCE, SETTINGS, (NULL),
-        ("Unable to set buffer time %i for playback: %s",
-            alsa->buffer_time, snd_strerror (err)));
-    return err;
-  }
 buffer_size:
   {
     GST_ELEMENT_ERROR (alsa, RESOURCE, SETTINGS, (NULL),
         ("Unable to get buffer size for playback: %s", snd_strerror (err)));
     return err;
   }
-period_time:
-  {
-    GST_ELEMENT_ERROR (alsa, RESOURCE, SETTINGS, (NULL),
-        ("Unable to set period time %i for playback: %s", alsa->period_time,
-            snd_strerror (err)));
-    return err;
-  }
 period_size:
   {
     GST_ELEMENT_ERROR (alsa, RESOURCE, SETTINGS, (NULL),