core: introduce new 'reference' volume for sinks

The reference volume is to be used as reference volume for stored stream
volumes. Previously if a new stream was created the relative volume was
taken relatively to the virtual device volume. Due to the flat volume
logic this could then be fed back to the virtual device volume.
Repeating the whole story over and over would result in a device volume
that would go lower, and lower and lower.

This patch introduces a 'reference' volume for each sink which stays
unmodified by stream volume changes even if flat volumes are used. It is
only modified if the sink volumes are modified directly by the user.

For further explanations see http://pulseaudio.org/wiki/InternalVolumes

1 files changed, 26 insertions, 16 deletions

diff --git a/src/pulsecore/sink.c b/src/pulsecore/sink.c
index 93800d14..30fa5579 100644
--- a/src/pulsecore/sink.c
+++ b/src/pulsecore/sink.c
@@ -202,7 +202,7 @@ pa_sink* pa_sink_new(
     s->inputs = pa_idxset_new(NULL, NULL);
     s->n_corked = 0;
 
-    s->virtual_volume = data->volume;
+    s->reference_volume = s->virtual_volume = data->volume;
     pa_cvolume_reset(&s->soft_volume, s->sample_spec.channels);
     s->base_volume = PA_VOLUME_NORM;
     s->n_volume_steps = PA_VOLUME_NORM+1;
@@ -351,11 +351,12 @@ void pa_sink_put(pa_sink* s) {
 
     if (!(s->flags & PA_SINK_HW_VOLUME_CTRL)) {
         s->flags |= PA_SINK_DECIBEL_VOLUME;
-
-        s->thread_info.soft_volume = s->soft_volume;
-        s->thread_info.soft_muted = s->muted;
+        s->base_volume = PA_VOLUME_NORM;
     }
 
+    s->thread_info.soft_volume = s->soft_volume;
+    s->thread_info.soft_muted = s->muted;
+
     if (s->flags & PA_SINK_DECIBEL_VOLUME)
         s->n_volume_steps = PA_VOLUME_NORM+1;
 
@@ -1046,16 +1047,16 @@ void pa_sink_update_flat_volume(pa_sink *s, pa_cvolume *new_volume) {
     pa_assert(PA_SINK_IS_LINKED(s->state));
     pa_assert(s->flags & PA_SINK_FLAT_VOLUME);
 
-    /* This is called whenever a sink input volume changes and we
-     * might need to fix up the sink volume accordingly. Please note
-     * that we don't actually update the sinks volume here, we only
-     * return how it needs to be updated. The caller should then call
-     * pa_sink_set_volume().*/
+    /* This is called whenever a sink input volume changes or a sink
+     * input is added/removed and we might need to fix up the sink
+     * volume accordingly. Please note that we don't actually update
+     * the sinks volume here, we only return how it needs to be
+     * updated. The caller should then call pa_sink_set_volume().*/
 
     if (pa_idxset_isempty(s->inputs)) {
         /* In the special case that we have no sink input we leave the
          * volume unmodified. */
-        *new_volume = s->virtual_volume;
+        *new_volume = s->reference_volume;
         return;
     }
 
@@ -1142,7 +1143,7 @@ void pa_sink_propagate_flat_volume(pa_sink *s) {
 }
 
 /* Called from main thread */
-void pa_sink_set_volume(pa_sink *s, const pa_cvolume *volume, pa_bool_t propagate, pa_bool_t sendmsg) {
+void pa_sink_set_volume(pa_sink *s, const pa_cvolume *volume, pa_bool_t propagate, pa_bool_t sendmsg, pa_bool_t become_reference) {
     pa_bool_t virtual_volume_changed;
 
     pa_sink_assert_ref(s);
@@ -1154,6 +1155,9 @@ void pa_sink_set_volume(pa_sink *s, const pa_cvolume *volume, pa_bool_t propagat
     virtual_volume_changed = !pa_cvolume_equal(volume, &s->virtual_volume);
     s->virtual_volume = *volume;
 
+    if (become_reference)
+        s->reference_volume = s->virtual_volume;
+
     /* Propagate this volume change back to the inputs */
     if (virtual_volume_changed)
         if (propagate && (s->flags & PA_SINK_FLAT_VOLUME))
@@ -1161,8 +1165,8 @@ void pa_sink_set_volume(pa_sink *s, const pa_cvolume *volume, pa_bool_t propagat
 
     if (s->set_volume) {
         /* If we have a function set_volume(), then we do not apply a
-         * soft volume by default. However, set_volume() is apply one
-         * to s->soft_volume */
+         * soft volume by default. However, set_volume() is free to
+         * apply one to s->soft_volume */
 
         pa_cvolume_reset(&s->soft_volume, s->sample_spec.channels);
         s->set_volume(s);
@@ -1194,7 +1198,7 @@ void pa_sink_set_soft_volume(pa_sink *s, const pa_cvolume *volume) {
 }
 
 /* Called from main thread */
-const pa_cvolume *pa_sink_get_volume(pa_sink *s, pa_bool_t force_refresh) {
+const pa_cvolume *pa_sink_get_volume(pa_sink *s, pa_bool_t force_refresh, pa_bool_t reference) {
     pa_sink_assert_ref(s);
 
     if (s->refresh_volume || force_refresh) {
@@ -1207,6 +1211,8 @@ const pa_cvolume *pa_sink_get_volume(pa_sink *s, pa_bool_t force_refresh) {
 
         if (!pa_cvolume_equal(&old_virtual_volume, &s->virtual_volume)) {
 
+            s->reference_volume = s->virtual_volume;
+
             if (s->flags & PA_SINK_FLAT_VOLUME)
                 pa_sink_propagate_flat_volume(s);
 
@@ -1214,7 +1220,7 @@ const pa_cvolume *pa_sink_get_volume(pa_sink *s, pa_bool_t force_refresh) {
         }
     }
 
-    return &s->virtual_volume;
+    return reference ? &s->reference_volume : &s->virtual_volume;
 }
 
 /* Called from main thread */
@@ -1226,7 +1232,11 @@ void pa_sink_volume_changed(pa_sink *s, const pa_cvolume *new_volume) {
     if (pa_cvolume_equal(&s->virtual_volume, new_volume))
         return;
 
-    s->virtual_volume = *new_volume;
+    s->reference_volume = s->virtual_volume = *new_volume;
+
+    if (s->flags & PA_SINK_FLAT_VOLUME)
+        pa_sink_propagate_flat_volume(s);
+
     pa_subscription_post(s->core, PA_SUBSCRIPTION_EVENT_SINK|PA_SUBSCRIPTION_EVENT_CHANGE, s->index);
 }