[pulseaudio-discuss] [PATCH 1/2] loopback: Add hooks to track port latency offsets

[Georg Chini]

The previous patch assumed constant port latency offsets. The offsets can
however be changed by the user, therefore these changes need to be tracked
as well. This patch adds the necessary hooks.
---
 src/modules/module-loopback.c | 38 ++++++++++++++++++++++++++++++++++++--
 src/pulsecore/core.h          |  2 ++
 src/pulsecore/sink.c          |  2 ++
 src/pulsecore/source.c        |  2 ++
 4 files changed, 42 insertions(+), 2 deletions(-)

diff --git a/src/modules/module-loopback.c b/src/modules/module-loopback.c
index 442bc8a9..e21a3b3b 100644
--- a/src/modules/module-loopback.c
+++ b/src/modules/module-loopback.c
@@ -1087,7 +1087,7 @@ static int loopback_process_msg_cb(pa_msgobject *o, int code, void *userdata, in
                  * source implementations. */
                 pa_log_warn("Source minimum latency increased to %0.2f ms", (double)current_latency / PA_USEC_PER_MSEC);
                 u->configured_source_latency = current_latency;
-                update_latency_boundaries(u, u->source_output->source, u->sink_input->sink, false);
+                update_latency_boundaries(u, u->source_output->source, u->sink_input->sink, true);
             }
 
             return 0;
@@ -1102,7 +1102,7 @@ static int loopback_process_msg_cb(pa_msgobject *o, int code, void *userdata, in
                  * implementations. */
                 pa_log_warn("Sink minimum latency increased to %0.2f ms", (double)current_latency / PA_USEC_PER_MSEC);
                 u->configured_sink_latency = current_latency;
-                update_latency_boundaries(u, u->source_output->source, u->sink_input->sink, false);
+                update_latency_boundaries(u, u->source_output->source, u->sink_input->sink, true);
             }
 
             return 0;
@@ -1111,6 +1111,34 @@ static int loopback_process_msg_cb(pa_msgobject *o, int code, void *userdata, in
     return 0;
 }
 
+static pa_hook_result_t sink_port_latency_offset_changed_cb(pa_core *core, pa_sink *sink, struct userdata *u) {
+
+    if (!u->sink_input->sink)
+        return PA_HOOK_OK;
+
+    if (sink != u->sink_input->sink)
+        return PA_HOOK_OK;
+
+    u->sink_latency_offset = sink->port_latency_offset;
+    update_minimum_latency(u, sink, true);
+
+    return PA_HOOK_OK;
+}
+
+static pa_hook_result_t source_port_latency_offset_changed_cb(pa_core *core, pa_source *source, struct userdata *u) {
+
+    if (!u->source_output->source)
+        return PA_HOOK_OK;
+
+    if (source != u->source_output->source)
+        return PA_HOOK_OK;
+
+    u->source_latency_offset = source->port_latency_offset;
+    update_minimum_latency(u, u->sink_input->sink, true);
+
+    return PA_HOOK_OK;
+}
+
 int pa__init(pa_module *m) {
     pa_modargs *ma = NULL;
     struct userdata *u;
@@ -1383,6 +1411,12 @@ int pa__init(pa_module *m) {
             && (n = pa_proplist_gets(u->source_output->source->proplist, PA_PROP_DEVICE_ICON_NAME)))
         pa_proplist_sets(u->sink_input->proplist, PA_PROP_MEDIA_ICON_NAME, n);
 
+    /* Hooks to track changes of latency offsets */
+    pa_module_hook_connect(m, &m->core->hooks[PA_CORE_HOOK_SINK_PORT_LATENCY_OFFSET_CHANGED],
+                           PA_HOOK_NORMAL, (pa_hook_cb_t) sink_port_latency_offset_changed_cb, u);
+    pa_module_hook_connect(m, &m->core->hooks[PA_CORE_HOOK_SOURCE_PORT_LATENCY_OFFSET_CHANGED],
+                           PA_HOOK_NORMAL, (pa_hook_cb_t) source_port_latency_offset_changed_cb, u);
+
     /* Setup message handler for main thread */
     u->msg = pa_msgobject_new(loopback_msg);
     u->msg->parent.process_msg = loopback_process_msg_cb;
diff --git a/src/pulsecore/core.h b/src/pulsecore/core.h
index 212f6f71..df71a118 100644
--- a/src/pulsecore/core.h
+++ b/src/pulsecore/core.h
@@ -75,6 +75,7 @@ typedef enum pa_core_hook {
     PA_CORE_HOOK_SINK_FLAGS_CHANGED,
     PA_CORE_HOOK_SINK_VOLUME_CHANGED,
     PA_CORE_HOOK_SINK_MUTE_CHANGED,
+    PA_CORE_HOOK_SINK_PORT_LATENCY_OFFSET_CHANGED,
     PA_CORE_HOOK_SOURCE_NEW,
     PA_CORE_HOOK_SOURCE_FIXATE,
     PA_CORE_HOOK_SOURCE_PUT,
@@ -86,6 +87,7 @@ typedef enum pa_core_hook {
     PA_CORE_HOOK_SOURCE_FLAGS_CHANGED,
     PA_CORE_HOOK_SOURCE_VOLUME_CHANGED,
     PA_CORE_HOOK_SOURCE_MUTE_CHANGED,
+    PA_CORE_HOOK_SOURCE_PORT_LATENCY_OFFSET_CHANGED,
     PA_CORE_HOOK_SINK_INPUT_NEW,
     PA_CORE_HOOK_SINK_INPUT_FIXATE,
     PA_CORE_HOOK_SINK_INPUT_PUT,
diff --git a/src/pulsecore/sink.c b/src/pulsecore/sink.c
index fb16d574..39689437 100644
--- a/src/pulsecore/sink.c
+++ b/src/pulsecore/sink.c
@@ -3295,6 +3295,8 @@ void pa_sink_set_port_latency_offset(pa_sink *s, int64_t offset) {
         pa_assert_se(pa_asyncmsgq_send(s->asyncmsgq, PA_MSGOBJECT(s), PA_SINK_MESSAGE_SET_PORT_LATENCY_OFFSET, NULL, offset, NULL) == 0);
     else
         s->thread_info.port_latency_offset = offset;
+
+    pa_hook_fire(&s->core->hooks[PA_CORE_HOOK_SINK_PORT_LATENCY_OFFSET_CHANGED], s);
 }
 
 /* Called from main context */
diff --git a/src/pulsecore/source.c b/src/pulsecore/source.c
index 09c953f1..14250825 100644
--- a/src/pulsecore/source.c
+++ b/src/pulsecore/source.c
@@ -2586,6 +2586,8 @@ void pa_source_set_port_latency_offset(pa_source *s, int64_t offset) {
         pa_assert_se(pa_asyncmsgq_send(s->asyncmsgq, PA_MSGOBJECT(s), PA_SOURCE_MESSAGE_SET_PORT_LATENCY_OFFSET, NULL, offset, NULL) == 0);
     else
         s->thread_info.port_latency_offset = offset;
+
+    pa_hook_fire(&s->core->hooks[PA_CORE_HOOK_SOURCE_PORT_LATENCY_OFFSET_CHANGED], s);
 }
 
 /* Called from main thread */
-- 
2.11.0