libuv add idle processing to force service where needed

https://github.com/warmcat/libwebsockets/issues/485

Signed-off-by: Andy Green <andy@warmcat.com>

lib/libuv.c

@@ -30,11 +30,36 @@ lws_feature_status_libuv(struct lws_context_creation_info *info)
 		lwsl_notice("libuv support compiled in but disabled\n");
 }
 
+static void
+lws_uv_idle(uv_idle_t *handle)
+{
+	struct lws_context_per_thread *pt = container_of(handle,
+					struct lws_context_per_thread, uv_idle);
+
+	lwsl_debug("%s\n", __func__);
+
+	/*
+	 * is there anybody with pending stuff that needs service forcing?
+	 */
+	if (!lws_service_adjust_timeout(pt->context, 1, pt->tid)) {
+		/* -1 timeout means just do forced service */
+		lws_plat_service_tsi(pt->context, -1, pt->tid);
+		/* still somebody left who wants forced service? */
+		if (!lws_service_adjust_timeout(pt->context, 1, pt->tid))
+			/* yes... come back again later */
+			return;
+	}
+
+	/* there is nobody who needs service forcing, shut down idle */
+	uv_idle_stop(handle);
+}
+
 static void
 lws_io_cb(uv_poll_t *watcher, int status, int revents)
 {
 	struct lws_io_watcher *lws_io = container_of(watcher,
 					struct lws_io_watcher, uv_watcher);
+	struct lws *wsi = container_of(lws_io, struct lws, w_read);
 	struct lws_context *context = lws_io->context;
 	struct lws_pollfd eventfd;
 
@@ -67,6 +92,8 @@ lws_io_cb(uv_poll_t *watcher, int status, int revents)
 		}
 	}
 	lws_service_fd(context, &eventfd);
+
+	uv_idle_start(&context->pt[(int)wsi->tsi].uv_idle, lws_uv_idle);
 }
 
 LWS_VISIBLE void
@@ -96,7 +123,7 @@ lws_uv_timeout_cb(uv_timer_t *timer)
 			struct lws_context_per_thread, uv_timeout_watcher);
 
 	lwsl_debug("%s\n", __func__);
-	/* do timeout check only */
+
 	lws_service_fd_tsi(pt->context, NULL, pt->tid);
 }
 
@@ -117,6 +144,7 @@ lws_uv_initloop(struct lws_context *context, uv_loop_t *loop, int tsi)
 		pt->ev_loop_foreign = 1;
 
 	pt->io_loop_uv = loop;
+	uv_idle_init(loop, &pt->uv_idle);
 
 	if (pt->context->use_ev_sigint) {
 		assert(ARRAY_SIZE(sigs) <= ARRAY_SIZE(pt->signals));

lib/lws-plat-unix.c

@@ -122,7 +122,7 @@ LWS_VISIBLE int
 lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 {
 	struct lws_context_per_thread *pt = &context->pt[tsi];
-	int n, m, c;
+	int n = -1, m, c;
 	char buf;
 
 	/* stay dead once we are dead */
@@ -130,6 +130,9 @@ lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 	if (!context || !context->vhost_list)
 		return 1;
 
+	if (timeout_ms < 0)
+		goto faked_service;
+
 	lws_libev_run(context, tsi);
 	lws_libuv_run(context, tsi);
 
@@ -139,7 +142,8 @@ lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 		memset(&_lws, 0, sizeof(_lws));
 		_lws.context = context;
 
-		context->service_tid_detected = context->vhost_list->protocols[0].callback(
+		context->service_tid_detected =
+			context->vhost_list->protocols[0].callback(
 			&_lws, LWS_CALLBACK_GET_THREAD_ID, NULL, NULL, 0);
 	}
 	context->service_tid = context->service_tid_detected;
@@ -158,6 +162,7 @@ lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 		return 0;
 	}
 
+faked_service:
 	m = lws_service_flag_pending(context, tsi);
 	if (m)
 		c = -1; /* unknown limit */

lib/lws-plat-win.c

@@ -177,6 +177,9 @@ lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 	}
 	context->service_tid = context->service_tid_detected;
 
+	if (timeout_ms < 0)
+		goto faked_service;
+
 	for (i = 0; i < pt->fds_count; ++i) {
 		pfd = &pt->fds[i];
 
@@ -236,6 +239,8 @@ lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 			wsi->sock_send_blocking = 0;
 	}
 
+faked_service:
+
 	/* if someone faked their LWS_POLLIN, then go through all active fds */
 
 	if (lws_service_flag_pending(context, tsi)) {
@@ -254,6 +259,9 @@ lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 		return 0;
 	}
 
+	if (timeout_ms < 0)
+		return 0;
+
 	/* otherwise just do the one... must be a way to improve that... */
 
 	return lws_service_fd_tsi(context, pfd, tsi);

lib/private-libwebsockets.h

@@ -598,6 +598,7 @@ struct lws_context_per_thread {
 	uv_loop_t *io_loop_uv;
 	uv_signal_t signals[8];
 	uv_timer_t uv_timeout_watcher;
+	uv_idle_t uv_idle;
 #endif
 #if defined(LWS_USE_LIBEV)
 	struct lws_io_watcher w_accept;