custom_event: fake_POLLIN_override

As discussed in

#3219

Author: lws-team

include/libwebsockets/lws-eventlib-exports.h

@@ -67,6 +67,9 @@ struct lws_event_loop_ops {
 	void (*destroy_wsi)(struct lws *wsi);
 	/* return nonzero if caller thread is not loop service thread  */
 	int (*foreign_thread)(struct lws_context *context, int tsi);
+	/* optional: custom implementation for faking POLLIN for buffered.
+	 *           return nonzero if any wsi faked */
+	int (*fake_POLLIN_override)(struct lws_context *context, int tsi);
 
 	uint8_t	flags;
 

lib/event-libs/glib/glib.c

@@ -491,6 +491,7 @@ static const struct lws_event_loop_ops event_loop_ops_glib = {
 	/* destroy_pt */		elops_destroy_pt_glib,
 	/* destroy wsi */		elops_destroy_wsi_glib,
 	/* foreign_thread */		NULL,
+	/* fake_POLLIN */		NULL,
 
 	/* flags */			LELOF_DESTROY_FINAL,
 

lib/event-libs/libev/libev.c

@@ -443,6 +443,7 @@ static const struct lws_event_loop_ops event_loop_ops_ev = {
 	/* destroy_pt */		elops_destroy_pt_ev,
 	/* destroy wsi */		elops_destroy_wsi_ev,
 	/* foreign_thread */		NULL,
+	/* fake_POLLIN */		NULL,
 
 	/* flags */			0,
 

lib/event-libs/libevent/libevent.c

@@ -495,6 +495,7 @@ static const struct lws_event_loop_ops event_loop_ops_event = {
 	/* destroy_pt */		elops_destroy_pt_event,
 	/* destroy wsi */		elops_destroy_wsi_event,
 	/* foreign_thread */		NULL,
+	/* fake_POLLIN */		NULL,
 
 	/* flags */			0,
 

lib/event-libs/libuv/libuv.c

@@ -926,6 +926,7 @@ static const struct lws_event_loop_ops event_loop_ops_uv = {
 	/* destroy_pt */		elops_destroy_pt_uv,
 	/* destroy wsi */		NULL,
 	/* foreign_thread */		elops_foreign_thread_uv,
+	/* fake_POLLIN */		NULL,
 
 	/* flags */			0,
 

lib/event-libs/uloop/uloop.c

@@ -301,6 +301,7 @@ static const struct lws_event_loop_ops event_loop_ops_uloop = {
 	/* destroy_pt */		elops_destroy_pt_uloop,
 	/* destroy wsi */		elops_destroy_wsi_uloop,
 	/* foreign_thread */		NULL,
+	/* fake_POLLIN */		NULL,
 
 	/* flags */			0,
 

lib/tls/tls-network.c

@@ -40,12 +40,23 @@ lws_tls_fake_POLLIN_for_buffered(struct lws_context_per_thread *pt)
 		struct lws *wsi = lws_container_of(p, struct lws,
 						   tls.dll_pending_tls);
 
-		if (wsi->position_in_fds_table >= 0) {
-
-			pt->fds[wsi->position_in_fds_table].revents = (short)
-				(pt->fds[wsi->position_in_fds_table].revents |
-				 (pt->fds[wsi->position_in_fds_table].events & LWS_POLLIN));
-			ret |= pt->fds[wsi->position_in_fds_table].revents & LWS_POLLIN;
+		/*
+		 * ... allow custom event loop to override our POLLIN-setting
+		 * implementation if it knows how to do it better for its case
+		 */
+					   
+		if (pt->context->event_loop_ops &&
+		    pt->context->event_loop_ops->fake_POLLIN_override)
+			pt->context->event_loop_ops->fake_POLLIN_override(
+							pt->context, pt->tid);
+		else {					
+			if (wsi->position_in_fds_table >= 0) {
+
+				pt->fds[wsi->position_in_fds_table].revents = (short)
+					(pt->fds[wsi->position_in_fds_table].revents |
+					 (pt->fds[wsi->position_in_fds_table].events & LWS_POLLIN));
+				ret |= pt->fds[wsi->position_in_fds_table].revents & LWS_POLLIN;
+			}
 		}
 
 	} lws_end_foreach_dll_safe(p, p1);