From edea0fc4b52ebe7888b9a8e0b245d9dc50ac461e Mon Sep 17 00:00:00 2001
From: Pierre Ossman <ossman@cendio.se>
Date: Fri, 17 Jul 2015 10:38:49 +0200
Subject: [PATCH 2/3] tunnel-new: respect client latency requirements better

Tell the upstream server to adjust the total latency, as that better
matches what our clients are requesting out of us. Also let the
upstream server pick the record latency when we have no preferences.

Signed-off-by: Pierre Ossman <ossman@cendio.se>
---
 src/modules/module-tunnel-sink-new.c   |  2 +-
 src/modules/module-tunnel-source-new.c | 24 +++++++++++-------------
 2 files changed, 12 insertions(+), 14 deletions(-)

diff --git a/src/modules/module-tunnel-sink-new.c b/src/modules/module-tunnel-sink-new.c
index c9be85b..a34ffea 100644
--- a/src/modules/module-tunnel-sink-new.c
+++ b/src/modules/module-tunnel-sink-new.c
@@ -355,7 +355,7 @@ static void context_state_cb(pa_context *c, void *userdata) {
             if (pa_stream_connect_playback(u->stream,
                                            u->remote_sink_name,
                                            &bufferattr,
-                                           PA_STREAM_INTERPOLATE_TIMING | PA_STREAM_DONT_MOVE | PA_STREAM_START_CORKED | PA_STREAM_AUTO_TIMING_UPDATE,
+                                           PA_STREAM_INTERPOLATE_TIMING | PA_STREAM_DONT_MOVE | PA_STREAM_START_CORKED | PA_STREAM_AUTO_TIMING_UPDATE | PA_STREAM_ADJUST_LATENCY,
                                            NULL,
                                            NULL) < 0) {
                 pa_log_error("Could not connect stream.");
diff --git a/src/modules/module-tunnel-source-new.c b/src/modules/module-tunnel-source-new.c
index d96ce67..c3ef936 100644
--- a/src/modules/module-tunnel-source-new.c
+++ b/src/modules/module-tunnel-source-new.c
@@ -83,6 +83,8 @@ struct userdata {
     bool connected;
     bool new_data;
 
+    pa_usec_t req_latency;
+
     char *cookie_file;
     char *remote_server;
     char *remote_source_name;
@@ -306,7 +308,6 @@ static void context_state_cb(pa_context *c, void *userdata) {
         case PA_CONTEXT_READY: {
             pa_proplist *proplist;
             pa_buffer_attr bufferattr;
-            pa_usec_t requested_latency;
             pa_operation *operation;
             char *username = pa_get_user_name_malloc();
             char *hostname = pa_get_host_name_malloc();
@@ -333,19 +334,18 @@ static void context_state_cb(pa_context *c, void *userdata) {
                 return;
             }
 
-            requested_latency = pa_source_get_requested_latency_within_thread(u->source);
-            if (requested_latency == (uint32_t) -1)
-                requested_latency = u->source->thread_info.max_latency;
+            u->req_latency = pa_source_get_requested_latency_within_thread(u->source);
 
             reset_bufferattr(&bufferattr);
-            bufferattr.fragsize = pa_usec_to_bytes(requested_latency, &u->source->sample_spec);
+            if (u->req_latency != (pa_usec_t) -1)
+                bufferattr.fragsize = pa_usec_to_bytes(u->req_latency, &u->source->sample_spec);
 
             pa_stream_set_state_callback(u->stream, stream_state_cb, userdata);
             pa_stream_set_read_callback(u->stream, stream_read_cb, userdata);
             if (pa_stream_connect_record(u->stream,
                                          u->remote_source_name,
                                          &bufferattr,
-                                         PA_STREAM_INTERPOLATE_TIMING|PA_STREAM_DONT_MOVE|PA_STREAM_AUTO_TIMING_UPDATE|PA_STREAM_START_CORKED) < 0) {
+                                         PA_STREAM_INTERPOLATE_TIMING|PA_STREAM_DONT_MOVE|PA_STREAM_AUTO_TIMING_UPDATE|PA_STREAM_START_CORKED|PA_STREAM_ADJUST_LATENCY) < 0) {
                 pa_log_debug("Could not create stream: %s", pa_strerror(pa_context_errno(u->context)));
                 u->thread_mainloop_api->quit(u->thread_mainloop_api, TUNNEL_THREAD_FAILED_MAINLOOP);
             }
@@ -424,7 +424,6 @@ static void subscribe_cb(pa_context *context, pa_subscription_event_type_t t, ui
 static void source_update_requested_latency_cb(pa_source *s) {
     struct userdata *u;
     pa_operation *operation;
-    size_t nbytes;
     pa_usec_t block_usec;
     pa_buffer_attr bufferattr;
 
@@ -432,19 +431,18 @@ static void source_update_requested_latency_cb(pa_source *s) {
     pa_assert_se(u = s->userdata);
 
     block_usec = pa_source_get_requested_latency_within_thread(s);
-    if (block_usec == (pa_usec_t) -1)
-        block_usec = s->thread_info.max_latency;
-
-    nbytes = pa_usec_to_bytes(block_usec, &s->sample_spec);
 
     if (u->stream) {
         switch (pa_stream_get_state(u->stream)) {
             case PA_STREAM_READY:
-                if (pa_stream_get_buffer_attr(u->stream)->fragsize == nbytes)
+                if (u->req_latency == block_usec)
                     break;
 
+                u->req_latency = block_usec;
+
                 reset_bufferattr(&bufferattr);
-                bufferattr.fragsize = nbytes;
+                if (u->req_latency != (pa_usec_t) -1)
+                    bufferattr.fragsize = pa_usec_to_bytes(u->req_latency, &s->sample_spec);
                 if ((operation = pa_stream_set_buffer_attr(u->stream, &bufferattr, NULL, NULL)))
                     pa_operation_unref(operation);
                 break;
-- 
2.4.3