From 196fe8b51bc19b0770fd1a7b7d4c25708c2ec64f Mon Sep 17 00:00:00 2001
From: Wim Taymans <wtaymans@redhat.com>
Date: Fri, 12 Mar 2021 15:58:34 +0100
Subject: [PATCH] jack: use configured node.latency when inactive

In the inactive state, use the configured latency values for the
node instead of the current values used in the graph. We need to
do this because the graph only changes the buffer-size to our
requirements when the node becomes active.

Some clients do get_buffer_size before activating and would then
get a different value from when they would activate, causing some
apps to be confused and stop.

See #886
---
 pipewire-jack/src/pipewire-jack.c | 54 +++++++++++++++++++++++--------
 1 file changed, 40 insertions(+), 14 deletions(-)

diff --git a/pipewire-jack/src/pipewire-jack.c b/pipewire-jack/src/pipewire-jack.c
index 85d406ec9..e9b41135d 100644
--- a/pipewire-jack/src/pipewire-jack.c
+++ b/pipewire-jack/src/pipewire-jack.c
@@ -320,6 +320,7 @@ struct client {
 	struct spa_io_position *position;
 	uint32_t sample_rate;
 	uint32_t buffer_frames;
+	struct spa_fraction latency;
 
 	struct spa_list free_mix;
 
@@ -2574,6 +2575,7 @@ jack_client_t * jack_client_open (const char *client_name,
 
 	client->buffer_frames = (uint32_t)-1;
 	client->sample_rate = (uint32_t)-1;
+	client->latency = SPA_FRACTION(-1, -1);
 
         spa_list_init(&client->free_mix);
 
@@ -2602,6 +2604,14 @@ jack_client_t * jack_client_open (const char *client_name,
 			&client->registry_listener,
 			&registry_events, client);
 
+	if ((str = getenv("PIPEWIRE_LATENCY")) != NULL)
+		pw_properties_set(client->props, PW_KEY_NODE_LATENCY, str);
+	if ((str = pw_properties_get(client->props, PW_KEY_NODE_LATENCY)) != NULL) {
+		uint32_t num, denom;
+		if (sscanf(str, "%u/%u", &num, &denom) == 2 && denom != 0) {
+			client->latency = SPA_FRACTION(num, denom);
+		}
+	}
 	if (pw_properties_get(client->props, PW_KEY_NODE_NAME) == NULL)
 		pw_properties_set(client->props, PW_KEY_NODE_NAME, client_name);
 	if (pw_properties_get(client->props, PW_KEY_NODE_DESCRIPTION) == NULL)
@@ -2612,8 +2622,6 @@ jack_client_t * jack_client_open (const char *client_name,
 		pw_properties_set(client->props, PW_KEY_MEDIA_CATEGORY, "Duplex");
 	if (pw_properties_get(client->props, PW_KEY_MEDIA_ROLE) == NULL)
 		pw_properties_set(client->props, PW_KEY_MEDIA_ROLE, "DSP");
-	if ((str = getenv("PIPEWIRE_LATENCY")) != NULL)
-		pw_properties_set(client->props, PW_KEY_NODE_LATENCY, str);
 	if (pw_properties_get(client->props, PW_KEY_NODE_ALWAYS_PROCESS) == NULL)
 		pw_properties_set(client->props, PW_KEY_NODE_ALWAYS_PROCESS, "true");
 
@@ -3260,28 +3268,46 @@ SPA_EXPORT
 jack_nframes_t jack_get_sample_rate (jack_client_t *client)
 {
 	struct client *c = (struct client *) client;
+	jack_nframes_t res = -1;
+
 	spa_return_val_if_fail(c != NULL, 0);
-	if (c->sample_rate == (uint32_t)-1) {
-		if (c->rt.position)
-			return c->rt.position->clock.rate.denom;
-		if (c->position)
-			return c->position->clock.rate.denom;
+
+	if (!c->active)
+		res = c->latency.denom;
+	if (c->active || res == (uint32_t)-1) {
+		res = c->sample_rate;
+		if (res == (uint32_t)-1) {
+			if (c->rt.position)
+				res = c->rt.position->clock.rate.denom;
+			else if (c->position)
+				res = c->position->clock.rate.denom;
+		}
 	}
-	return c->sample_rate;
+	pw_log_info("sample_rate: %u", res);
+	return res;
 }
 
 SPA_EXPORT
 jack_nframes_t jack_get_buffer_size (jack_client_t *client)
 {
 	struct client *c = (struct client *) client;
+	jack_nframes_t res = -1;
+
 	spa_return_val_if_fail(c != NULL, 0);
-	if (c->buffer_frames == (uint32_t)-1) {
-		if (c->rt.position)
-			return c->rt.position->clock.duration;
-		if (c->position)
-			return c->position->clock.duration;
+
+	if (!c->active)
+		res = c->latency.num;
+	if (c->active || res == (uint32_t)-1) {
+		res = c->buffer_frames;
+		if (res == (uint32_t)-1) {
+			if (c->rt.position)
+				res = c->rt.position->clock.duration;
+			else if (c->position)
+				res = c->position->clock.duration;
+		}
 	}
-	return c->buffer_frames;
+	pw_log_info("buffer_frames: %u", res);
+	return res;
 }
 
 SPA_EXPORT