sink, source: Add API to update sample spec

This is useful to have visibility into when the whole sample spec
changes at runtime (during reconfiguration, for example).

src/modules/module-null-sink.c

@@ -178,8 +178,9 @@ static void sink_update_requested_latency_cb(pa_sink *s) {
 }
 
 static int sink_reconfigure_cb(pa_sink *s, pa_sample_spec *spec, pa_channel_map *map, bool passthrough) {
-    /* We don't need to do anything */
+    pa_sink_assert_ref(s);
-    s->sample_spec = *spec;
+
+    pa_sink_set_sample_spec(s, spec);
 
     if (map)
         pa_sink_set_channel_map(s, map);

src/pulsecore/sink.c

@@ -4046,6 +4046,28 @@ done:
     return out_formats;
 }
 
+/* Called from the main thread */
+void pa_sink_set_sample_spec(pa_sink *s, pa_sample_spec *spec) {
+    pa_sample_spec old_spec;
+    char spec_str[PA_SAMPLE_SPEC_SNPRINT_MAX], old_spec_str[PA_SAMPLE_SPEC_SNPRINT_MAX];
+
+    pa_assert(s);
+    pa_assert(pa_sample_spec_valid(spec));
+
+    old_spec = s->sample_spec;
+    if (pa_sample_spec_equal(&old_spec, spec))
+        return;
+
+    pa_sample_spec_snprint(spec_str, sizeof(spec_str), spec);
+    pa_sample_spec_snprint(old_spec_str, sizeof(old_spec_str), &old_spec);
+
+    pa_log_info("%s: spec: %s -> %s", s->name, old_spec_str, spec_str);
+
+    s->sample_spec = *spec;
+
+    pa_subscription_post(s->core, PA_SUBSCRIPTION_EVENT_SINK | PA_SUBSCRIPTION_EVENT_CHANGE, s->index);
+}
+
 /* Called from the main thread */
 void pa_sink_set_sample_format(pa_sink *s, pa_sample_format_t format) {
     pa_sample_format_t old_format;

src/pulsecore/sink.h

@@ -527,6 +527,7 @@ bool pa_sink_set_formats(pa_sink *s, pa_idxset *formats);
 bool pa_sink_check_format(pa_sink *s, pa_format_info *f);
 pa_idxset* pa_sink_check_formats(pa_sink *s, pa_idxset *in_formats);
 
+void pa_sink_set_sample_spec(pa_sink *s, pa_sample_spec *spec);
 void pa_sink_set_sample_format(pa_sink *s, pa_sample_format_t format);
 void pa_sink_set_sample_rate(pa_sink *s, uint32_t rate);
 void pa_sink_set_channels(pa_sink *s, uint8_t channels);

src/pulsecore/source.c

@@ -3040,6 +3040,28 @@ done:
     return out_formats;
 }
 
+/* Called from the main thread */
+void pa_source_set_sample_spec(pa_source *s, pa_sample_spec *spec) {
+    pa_sample_spec old_spec;
+    char spec_str[PA_SAMPLE_SPEC_SNPRINT_MAX], old_spec_str[PA_SAMPLE_SPEC_SNPRINT_MAX];
+
+    pa_assert(s);
+    pa_assert(pa_sample_spec_valid(spec));
+
+    old_spec = s->sample_spec;
+    if (pa_sample_spec_equal(&old_spec, spec))
+        return;
+
+    pa_sample_spec_snprint(spec_str, sizeof(spec_str), spec);
+    pa_sample_spec_snprint(old_spec_str, sizeof(old_spec_str), &old_spec);
+
+    pa_log_info("%s: spec: %s -> %s", s->name, old_spec_str, spec_str);
+
+    s->sample_spec = *spec;
+
+    pa_subscription_post(s->core, PA_SUBSCRIPTION_EVENT_SOURCE | PA_SUBSCRIPTION_EVENT_CHANGE, s->index);
+}
+
 /* Called from the main thread */
 void pa_source_set_sample_format(pa_source *s, pa_sample_format_t format) {
     pa_sample_format_t old_format;

src/pulsecore/source.h

@@ -448,6 +448,7 @@ pa_idxset* pa_source_get_formats(pa_source *s);
 bool pa_source_check_format(pa_source *s, pa_format_info *f);
 pa_idxset* pa_source_check_formats(pa_source *s, pa_idxset *in_formats);
 
+void pa_source_set_sample_spec(pa_source *s, pa_sample_spec *spec);
 void pa_source_set_sample_format(pa_source *s, pa_sample_format_t format);
 void pa_source_set_sample_rate(pa_source *s, uint32_t rate);
 void pa_source_set_channels(pa_source *s, uint8_t channels);