Don't stop hardware on buffer underruns. Instead continue playing to guarantee that our time function stays as linear as possible.

git-svn-id: file:///home/lennart/svn/public/pulseaudio/branches/lennart@1566 fefdeb5f-60dc-0310-8127-8f9354f1896f

4 files changed, 91 insertions, 49 deletions

diff --git a/src/modules/alsa-util.c b/src/modules/alsa-util.c
index dd9ac79e..dd063f3b 100644
--- a/src/modules/alsa-util.c
+++ b/src/modules/alsa-util.c
@@ -289,10 +289,11 @@ int pa_alsa_set_hw_params(snd_pcm_t *pcm_handle, pa_sample_spec *ss, uint32_t *p
     pa_assert(periods);
     pa_assert(period_size);
 
+    snd_pcm_hw_params_alloca(&hwparams);
+    
     buffer_size = *periods * *period_size;
 
-    if ((ret = snd_pcm_hw_params_malloc(&hwparams)) < 0 ||
-        (ret = snd_pcm_hw_params_any(pcm_handle, hwparams)) < 0 ||
+    if ((ret = snd_pcm_hw_params_any(pcm_handle, hwparams)) < 0 ||
         (ret = snd_pcm_hw_params_set_rate_resample(pcm_handle, hwparams, 0)) < 0)
         goto finish;
 
@@ -355,12 +356,36 @@ int pa_alsa_set_hw_params(snd_pcm_t *pcm_handle, pa_sample_spec *ss, uint32_t *p
     ret = 0;
 
 finish:
-    if (hwparams)
-        snd_pcm_hw_params_free(hwparams);
 
     return ret;
 }
 
+int pa_alsa_set_sw_params(snd_pcm_t *pcm) {
+    snd_pcm_sw_params_t *swparams;
+    int err;
+    
+    pa_assert(pcm);
+
+    snd_pcm_sw_params_alloca(&swparams);
+
+    if ((err = snd_pcm_sw_params_current(pcm, swparams) < 0)) {
+        pa_log_warn("Unable to determine current swparams: %s\n", snd_strerror(err));
+        return err;
+    }
+
+    if ((err = snd_pcm_sw_params_set_stop_threshold(pcm, swparams, (snd_pcm_uframes_t) -1)) < 0) {
+        pa_log_warn("Unable to set stop threshold: %s\n", snd_strerror(err));
+        return err;
+    }
+    
+    if ((err = snd_pcm_sw_params(pcm, swparams)) < 0) {
+        pa_log_warn("Unable to set sw params: %s\n", snd_strerror(err));
+        return err;
+    }
+
+    return 0;
+}
+
 int pa_alsa_prepare_mixer(snd_mixer_t *mixer, const char *dev) {
     int err;
 
diff --git a/src/modules/alsa-util.h b/src/modules/alsa-util.h
index f79325c6..6f1f927e 100644
--- a/src/modules/alsa-util.h
+++ b/src/modules/alsa-util.h
@@ -39,6 +39,7 @@ void pa_alsa_fdlist_free(struct pa_alsa_fdlist *fdl);
 int pa_alsa_fdlist_set_mixer(struct pa_alsa_fdlist *fdl, snd_mixer_t *mixer_handle, pa_mainloop_api* m);
 
 int pa_alsa_set_hw_params(snd_pcm_t *pcm_handle, pa_sample_spec *ss, uint32_t *periods, snd_pcm_uframes_t *period_size, int *use_mmap);
+int pa_alsa_set_sw_params(snd_pcm_t *pcm);
 
 int pa_alsa_prepare_mixer(snd_mixer_t *mixer, const char *dev);
 snd_mixer_elem_t *pa_alsa_find_elem(snd_mixer_t *mixer, const char *name, const char *fallback);
diff --git a/src/modules/module-alsa-sink.c b/src/modules/module-alsa-sink.c
index ced42ee3..5765d780 100644
--- a/src/modules/module-alsa-sink.c
+++ b/src/modules/module-alsa-sink.c
@@ -545,18 +545,23 @@ static void thread_func(void *userdata) {
                     goto fail;
 
             } else {
-                ssize_t l;
-
-                if ((err = snd_pcm_status(u->pcm_handle, status)) >= 0)
-                    l = snd_pcm_status_get_avail(status) * u->frame_size;
-                else
-                    l = u->fragment_size;
-
-                while (l > 0) {
+                for (;;) {
                     void *p;
                     snd_pcm_sframes_t t;
+                    ssize_t l;
+                
+                    if ((err = snd_pcm_status(u->pcm_handle, status)) < 0) {
+                        pa_log("Failed to query DSP status data: %s", snd_strerror(t));
+                        goto fail;
+                    }
 
-                    pa_assert(l > 0);
+                    if (snd_pcm_status_get_avail_max(status)*u->frame_size >= u->hwbuf_size)
+                        pa_log_debug("Buffer underrun!");
+                    
+                    l = snd_pcm_status_get_avail(status) * u->frame_size;
+
+                    if (l <= 0)
+                        break;
                     
                     if (u->memchunk.length <= 0)
                         pa_sink_render(u->sink, l, &u->memchunk);
@@ -573,10 +578,7 @@ static void thread_func(void *userdata) {
                     
                     if (t < 0) {
 
-                        if (t == -EPIPE) {
-                            pa_log_debug("Buffer underrun!");
-                            u->first = 1;
-                        }
+                        pa_assert(t != -EPIPE);
                         
                         if ((t = snd_pcm_recover(u->pcm_handle, t, 1)) == 0)
                             continue;
@@ -588,21 +590,20 @@ static void thread_func(void *userdata) {
                             pa_log("Failed to write data to DSP: %s", snd_strerror(t));
                             goto fail;
                         }
+                    }
                         
-                    } else {
-                        
-                        u->memchunk.index += t * u->frame_size;
-                        u->memchunk.length -= t * u->frame_size;
-                        
-                        if (u->memchunk.length <= 0) {
-                            pa_memblock_unref(u->memchunk.memblock);
-                            pa_memchunk_reset(&u->memchunk);
-                        }
-                        
-                        l -= t * u->frame_size;
-
-                        work_done = 1;
+                    u->memchunk.index += t * u->frame_size;
+                    u->memchunk.length -= t * u->frame_size;
+                    
+                    if (u->memchunk.length <= 0) {
+                        pa_memblock_unref(u->memchunk.memblock);
+                        pa_memchunk_reset(&u->memchunk);
                     }
+
+                    work_done = 1;
+
+                    if (t * u->frame_size >= (unsigned) l)
+                        break;
                 } 
             }
 
@@ -756,6 +757,11 @@ int pa__init(pa_core *c, pa_module*m) {
     if (u->use_mmap)
         pa_log_info("Successfully enabled mmap() mode.");
 
+    if ((err = pa_alsa_set_sw_params(u->pcm_handle)) < 0) {
+        pa_log("Failed to set software parameters: %s", snd_strerror(err));
+        goto fail;
+    }
+
     /* ALSA might tweak the sample spec, so recalculate the frame size */
     frame_size = pa_frame_size(&ss);
 
diff --git a/src/modules/module-alsa-source.c b/src/modules/module-alsa-source.c
index 0fd7bca0..9a5d5acb 100644
--- a/src/modules/module-alsa-source.c
+++ b/src/modules/module-alsa-source.c
@@ -533,19 +533,25 @@ static void thread_func(void *userdata) {
                     goto fail;
 
             } else {
-                ssize_t l;
 
-                if ((err = snd_pcm_status(u->pcm_handle, status)) >= 0)
-                    l = snd_pcm_status_get_avail(status) * u->frame_size;
-                else
-                    l = u->fragment_size;
-
-                while (l > 0) {
+                for (;;) {
                     void *p;
                     snd_pcm_sframes_t t;
+                    ssize_t l;
 
-                    pa_assert(l > 0);
+                    if ((err = snd_pcm_status(u->pcm_handle, status)) < 0) {
+                        pa_log("Failed to query DSP status data: %s", snd_strerror(t));
+                        goto fail;
+                    }
 
+                    if (snd_pcm_status_get_avail_max(status)*u->frame_size >= u->hwbuf_size)
+                        pa_log_debug("Buffer overrun!");
+                    
+                    l = snd_pcm_status_get_avail(status) * u->frame_size;
+
+                    if (l <= 0)
+                        break;
+                    
                     chunk.memblock = pa_memblock_new(u->core->mempool, l);
 
                     p = pa_memblock_acquire(chunk.memblock);
@@ -559,8 +565,7 @@ static void thread_func(void *userdata) {
                     if (t < 0) {
                         pa_memblock_unref(chunk.memblock);
 
-                        if (t == -EPIPE)
-                            pa_log_debug("Buffer underrun!");
+                        pa_assert(t != -EPIPE);
                         
                         if ((t = snd_pcm_recover(u->pcm_handle, t, 1)) == 0)
                             continue;
@@ -573,18 +578,18 @@ static void thread_func(void *userdata) {
                             goto fail;
                         }
                         
-                    } else {
+                    } 
                         
-                        chunk.index = 0;
-                        chunk.length = t * u->frame_size;
+                    chunk.index = 0;
+                    chunk.length = t * u->frame_size;
 
-                        pa_source_post(u->source, &chunk);
-                        pa_memblock_unref(chunk.memblock);
-                        
-                        l -= t * u->frame_size;
+                    pa_source_post(u->source, &chunk);
+                    pa_memblock_unref(chunk.memblock);
+                    
+                    work_done = 1;
 
-                        work_done = 1;
-                    }
+                    if (t * u->frame_size >= (unsigned) l)
+                        break;
                 } 
             }
 
@@ -730,6 +735,11 @@ int pa__init(pa_core *c, pa_module*m) {
 
     if (u->use_mmap)
         pa_log_info("Successfully enabled mmap() mode.");
+
+    if ((err = pa_alsa_set_sw_params(u->pcm_handle)) < 0) {
+        pa_log("Failed to set software parameters: %s", snd_strerror(err));
+        goto fail;
+    }
     
     /* ALSA might tweak the sample spec, so recalculate the frame size */
     frame_size = pa_frame_size(&ss);