add a 'volume factor' that is implicitly multiplied into the volume of a sink input without being visible to the outside

src/pulsecore/sink-input.c

@@ -79,6 +79,18 @@ void pa_sink_input_new_data_set_volume(pa_sink_input_new_data *data, const pa_cv
         data->volume = *volume;
 }
 
+void pa_sink_input_new_data_apply_volume_factor(pa_sink_input_new_data *data, const pa_cvolume *volume_factor) {
+    pa_assert(data);
+    pa_assert(volume_factor);
+
+    if (data->volume_factor_is_set)
+        pa_sw_cvolume_multiply(&data->volume_factor, &data->volume_factor, volume_factor);
+    else {
+        data->volume_factor_is_set = TRUE;
+        data->volume_factor = *volume_factor;
+    }
+}
+
 void pa_sink_input_new_data_set_muted(pa_sink_input_new_data *data, pa_bool_t mute) {
     pa_assert(data);
 
@@ -171,12 +183,17 @@ int pa_sink_input_new(
             pa_cvolume_reset(&data->volume, data->sample_spec.channels);
 
         data->save_volume = FALSE;
-
     }
 
     pa_return_val_if_fail(pa_cvolume_valid(&data->volume), -PA_ERR_INVALID);
     pa_return_val_if_fail(pa_cvolume_compatible(&data->volume, &data->sample_spec), -PA_ERR_INVALID);
 
+    if (!data->volume_factor_is_set)
+        pa_cvolume_reset(&data->volume_factor, data->sample_spec.channels);
+
+    pa_return_val_if_fail(pa_cvolume_valid(&data->volume_factor), -PA_ERR_INVALID);
+    pa_return_val_if_fail(pa_cvolume_compatible(&data->volume_factor, &data->sample_spec), -PA_ERR_INVALID);
+
     if (!data->muted_is_set)
         data->muted = FALSE;
 
@@ -259,6 +276,7 @@ int pa_sink_input_new(
     } else
         i->virtual_volume = data->volume;
 
+    i->volume_factor = data->volume_factor;
     pa_cvolume_init(&i->soft_volume);
     i->save_volume = data->save_volume;
     i->save_sink = data->save_sink;
@@ -500,7 +518,7 @@ void pa_sink_input_put(pa_sink_input *i) {
         pa_sink_update_flat_volume(i->sink, &new_volume);
         pa_sink_set_volume(i->sink, &new_volume, FALSE, FALSE);
     } else
-        i->soft_volume = i->virtual_volume;
+        pa_sw_cvolume_multiply(&i->soft_volume, &i->virtual_volume, &i->volume_factor);
 
     i->thread_info.soft_volume = i->soft_volume;
     i->thread_info.muted = i->muted;
@@ -874,8 +892,7 @@ void pa_sink_input_set_volume(pa_sink_input *i, const pa_cvolume *volume, pa_boo
 
         /* OK, we are in normal volume mode. The volume only affects
          * ourselves */
-
+        pa_sw_cvolume_multiply(&i->soft_volume, volume, &i->volume_factor);
-        i->soft_volume = *volume;
 
         /* Hooks have the ability to play games with i->soft_volume */
         pa_hook_fire(&i->core->hooks[PA_CORE_HOOK_SINK_INPUT_SET_VOLUME], i);
@@ -1066,7 +1083,7 @@ int pa_sink_input_start_move(pa_sink_input *i) {
 
         /* Make the absolute volume relative */
         i->virtual_volume = i->soft_volume;
-        pa_cvolume_reset(&i->soft_volume, i->sample_spec.channels);
+        i->soft_volume = i->volume_factor;
 
         /* We might need to update the sink's volume if we are in flat
          * volume mode. */

src/pulsecore/sink-input.h

@@ -91,7 +91,7 @@ struct pa_sink_input {
 
     pa_sink_input *sync_prev, *sync_next;
 
-    pa_cvolume virtual_volume, soft_volume;
+    pa_cvolume virtual_volume, soft_volume, volume_factor;
     pa_bool_t muted:1;
 
     /* if TRUE then the source we are connected to and/or the volume
@@ -233,13 +233,13 @@ typedef struct pa_sink_input_new_data {
     pa_sample_spec sample_spec;
     pa_channel_map channel_map;
 
-    pa_cvolume volume;
+    pa_cvolume volume, volume_factor;
     pa_bool_t muted:1;
 
     pa_bool_t sample_spec_is_set:1;
     pa_bool_t channel_map_is_set:1;
 
-    pa_bool_t volume_is_set:1;
+    pa_bool_t volume_is_set:1, volume_factor_is_set:1;
     pa_bool_t muted_is_set:1;
 
     pa_bool_t volume_is_absolute:1;
@@ -251,6 +251,7 @@ pa_sink_input_new_data* pa_sink_input_new_data_init(pa_sink_input_new_data *data
 void pa_sink_input_new_data_set_sample_spec(pa_sink_input_new_data *data, const pa_sample_spec *spec);
 void pa_sink_input_new_data_set_channel_map(pa_sink_input_new_data *data, const pa_channel_map *map);
 void pa_sink_input_new_data_set_volume(pa_sink_input_new_data *data, const pa_cvolume *volume);
+void pa_sink_input_new_data_apply_volume_factor(pa_sink_input_new_data *data, const pa_cvolume *volume_factor);
 void pa_sink_input_new_data_set_muted(pa_sink_input_new_data *data, pa_bool_t mute);
 void pa_sink_input_new_data_done(pa_sink_input_new_data *data);
 

src/pulsecore/sink.c

@@ -990,6 +990,7 @@ void pa_sink_update_flat_volume(pa_sink *s, pa_cvolume *new_volume) {
         remapped_new_volume = *new_volume;
         pa_cvolume_remap(&remapped_new_volume, &s->channel_map, &i->channel_map);
         pa_sw_cvolume_divide(&i->soft_volume, &i->virtual_volume, &remapped_new_volume);
+        pa_sw_cvolume_multiply(&i->soft_volume, &i->soft_volume, &i->volume_factor);
 
         /* Hooks have the ability to play games with i->soft_volume */
         pa_hook_fire(&s->core->hooks[PA_CORE_HOOK_SINK_INPUT_SET_VOLUME], i);