From 8f1e1b87526b6b409ca31287997c8f4ffd199a3c Mon Sep 17 00:00:00 2001
From: Andrew Kelley <superjoe30@gmail.com>
Date: Sat, 14 Nov 2015 21:44:03 -0700
Subject: [PATCH] ALSA: let alsa lib choose period settings

Closes #46
---
 src/alsa.c | 35 +++++++----------------------------
 src/alsa.h |  2 +-
 2 files changed, 8 insertions(+), 29 deletions(-)

diff --git a/src/alsa.c b/src/alsa.c
index 421b3f4..5bb8856 100644
--- a/src/alsa.c
+++ b/src/alsa.c
@@ -1312,34 +1312,7 @@ static int outstream_open_alsa(struct SoundIoPrivate *si, struct SoundIoOutStrea
         return SoundIoErrorOpeningDevice;
     }
 
-    int period_count;
-    if (device->is_raw) {
-        period_count = 4;
-        unsigned int microseconds = 0.25 * outstream->software_latency * 1000000.0;
-        if ((err = snd_pcm_hw_params_set_period_time_near(osa->handle, hwparams, &microseconds, NULL)) < 0) {
-            outstream_destroy_alsa(si, os);
-            return SoundIoErrorOpeningDevice;
-        }
-    } else {
-        period_count = 2;
-        double period_duration = 0.5 * outstream->software_latency;
-        snd_pcm_uframes_t period_frames =
-            ceil_dbl_to_uframes(period_duration * (double)outstream->sample_rate);
-
-        if ((err = snd_pcm_hw_params_set_period_size_near(osa->handle, hwparams, &period_frames, NULL)) < 0) {
-            outstream_destroy_alsa(si, os);
-            return SoundIoErrorOpeningDevice;
-        }
-    }
-
-    snd_pcm_uframes_t period_size;
-    if ((snd_pcm_hw_params_get_period_size(hwparams, &period_size, NULL)) < 0) {
-        outstream_destroy_alsa(si, os);
-        return SoundIoErrorOpeningDevice;
-    }
-    osa->period_size = period_size;
-
-    osa->buffer_size_frames = osa->period_size * period_count;
+    osa->buffer_size_frames = outstream->software_latency * outstream->sample_rate;
     if ((err = snd_pcm_hw_params_set_buffer_size_near(osa->handle, hwparams, &osa->buffer_size_frames)) < 0) {
         outstream_destroy_alsa(si, os);
         return SoundIoErrorOpeningDevice;
@@ -1352,6 +1325,12 @@ static int outstream_open_alsa(struct SoundIoPrivate *si, struct SoundIoOutStrea
         return (err == -EINVAL) ? SoundIoErrorIncompatibleDevice : SoundIoErrorOpeningDevice;
     }
 
+    if ((snd_pcm_hw_params_get_period_size(hwparams, &osa->period_size, NULL)) < 0) {
+        outstream_destroy_alsa(si, os);
+        return SoundIoErrorOpeningDevice;
+    }
+
+
     // set channel map
     osa->chmap->channels = ch_count;
     for (int i = 0; i < ch_count; i += 1) {
diff --git a/src/alsa.h b/src/alsa.h
index 25c5587..21271bf 100644
--- a/src/alsa.h
+++ b/src/alsa.h
@@ -59,7 +59,7 @@ struct SoundIoOutStreamAlsa {
     struct pollfd *poll_fds;
     struct SoundIoOsThread *thread;
     atomic_flag thread_exit_flag;
-    int period_size;
+    snd_pcm_uframes_t period_size;
     int write_frame_count;
     bool is_paused;
     atomic_flag clear_buffer_flag;