core: Link virtual sinks and sources to their streams.

This change doesn't add any functionality in itself, but it will be useful in
the future for operating on chains of sinks or sources that are piggy-backing
on each other.

For example, the PA_PROP_DEVICE_MASTER_DEVICE property could
be handled in the core so that each virtual device doesn't have to maintain it
separately. By using the origin_sink and destination_source pointers the core
is able to see at stream creation time that the stream is created by a virtual
device, and then update that device's property list using the name of the
master device that the stream is being connected to. The same thing can be done
also when the stream is being moved from a device to another, in which case the
_MASTER_DEVICE property needs updating.

8 files changed, 13 insertions, 2 deletions

diff --git a/src/pulsecore/sink-input.c b/src/pulsecore/sink-input.c
index 065fd2d3..00adc6d1 100644
--- a/src/pulsecore/sink-input.c
+++ b/src/pulsecore/sink-input.c
@@ -321,6 +321,7 @@ int pa_sink_input_new(
     i->driver = pa_xstrdup(pa_path_get_filename(data->driver));
     i->module = data->module;
     i->sink = data->sink;
+    i->origin_sink = data->origin_sink;
     i->client = data->client;
 
     i->requested_resample_method = data->resample_method;
diff --git a/src/pulsecore/sink-input.h b/src/pulsecore/sink-input.h
index f81e2d4b..e1991a26 100644
--- a/src/pulsecore/sink-input.h
+++ b/src/pulsecore/sink-input.h
@@ -83,7 +83,8 @@ struct pa_sink_input {
     pa_module *module;                  /* may be NULL */
     pa_client *client;                  /* may be NULL */
 
-    pa_sink *sink; /* NULL while we are being moved */
+    pa_sink *sink;                      /* NULL while we are being moved */
+    pa_sink *origin_sink;               /* only set by filter sinks */
 
     /* A sink input may be connected to multiple source outputs
      * directly, so that they don't get mixed data of the entire
@@ -285,6 +286,7 @@ typedef struct pa_sink_input_new_data {
     pa_client *client;
 
     pa_sink *sink;
+    pa_sink *origin_sink;
 
     pa_resample_method_t resample_method;
 
diff --git a/src/pulsecore/sink.c b/src/pulsecore/sink.c
index 62000e0d..0de544c9 100644
--- a/src/pulsecore/sink.c
+++ b/src/pulsecore/sink.c
@@ -269,6 +269,7 @@ pa_sink* pa_sink_new(
 
     s->inputs = pa_idxset_new(NULL, NULL);
     s->n_corked = 0;
+    s->input_to_master = NULL;
 
     s->reference_volume = s->real_volume = data->volume;
     pa_cvolume_reset(&s->soft_volume, s->sample_spec.channels);
diff --git a/src/pulsecore/sink.h b/src/pulsecore/sink.h
index 4d569ddc..8a515870 100644
--- a/src/pulsecore/sink.h
+++ b/src/pulsecore/sink.h
@@ -44,6 +44,7 @@ typedef struct pa_sink_volume_change pa_sink_volume_change;
 #include <pulsecore/card.h>
 #include <pulsecore/queue.h>
 #include <pulsecore/thread-mq.h>
+#include <pulsecore/sink-input.h>
 
 #define PA_MAX_INPUTS_PER_SINK 32
 
@@ -86,6 +87,7 @@ struct pa_sink {
     pa_idxset *inputs;
     unsigned n_corked;
     pa_source *monitor_source;
+    pa_sink_input *input_to_master;         /* non-NULL only for filter sinks */
 
     pa_volume_t base_volume; /* shall be constant */
     unsigned n_volume_steps; /* shall be constant */
diff --git a/src/pulsecore/source-output.c b/src/pulsecore/source-output.c
index 88731e76..0bb8899c 100644
--- a/src/pulsecore/source-output.c
+++ b/src/pulsecore/source-output.c
@@ -208,6 +208,7 @@ int pa_source_output_new(
     o->driver = pa_xstrdup(pa_path_get_filename(data->driver));
     o->module = data->module;
     o->source = data->source;
+    o->destination_source = data->destination_source;
     o->client = data->client;
 
     o->actual_resample_method = resampler ? pa_resampler_get_method(resampler) : PA_RESAMPLER_INVALID;
diff --git a/src/pulsecore/source-output.h b/src/pulsecore/source-output.h
index 273b78fc..f16f9520 100644
--- a/src/pulsecore/source-output.h
+++ b/src/pulsecore/source-output.h
@@ -74,7 +74,8 @@ struct pa_source_output {
     pa_module *module;                    /* may be NULL */
     pa_client *client;                    /* may be NULL */
 
-    pa_source *source; /* NULL while being moved */
+    pa_source *source;                    /* NULL while being moved */
+    pa_source *destination_source;        /* only set by filter sources */
 
     /* A source output can monitor just a single input of a sink, in which case we find it here */
     pa_sink_input *direct_on_input;       /* may be NULL */
@@ -211,6 +212,7 @@ typedef struct pa_source_output_new_data {
     pa_client *client;
 
     pa_source *source;
+    pa_source *destination_source;
 
     pa_resample_method_t resample_method;
 
diff --git a/src/pulsecore/source.c b/src/pulsecore/source.c
index 412a3db9..24d0ff6b 100644
--- a/src/pulsecore/source.c
+++ b/src/pulsecore/source.c
@@ -221,6 +221,7 @@ pa_source* pa_source_new(
     s->outputs = pa_idxset_new(NULL, NULL);
     s->n_corked = 0;
     s->monitor_of = NULL;
+    s->output_from_master = NULL;
 
     s->volume = data->volume;
     pa_cvolume_reset(&s->soft_volume, s->sample_spec.channels);
diff --git a/src/pulsecore/source.h b/src/pulsecore/source.h
index e3e56bc4..f3af159e 100644
--- a/src/pulsecore/source.h
+++ b/src/pulsecore/source.h
@@ -75,6 +75,7 @@ struct pa_source {
     pa_idxset *outputs;
     unsigned n_corked;
     pa_sink *monitor_of;                     /* may be NULL */
+    pa_source_output *output_from_master;    /* non-NULL only for filter sources */
 
     pa_volume_t base_volume; /* shall be constant */
     unsigned n_volume_steps; /* shall be constant */