From d784c2ad199533bf0c868e753961692cb0463ac3 Mon Sep 17 00:00:00 2001
From: Dmitry Simonenko <pmwkaa@gmail.com>
Date: Thu, 13 Jun 2019 11:55:01 +0300
Subject: [PATCH] odyssey: make restart read logic explicit in router attach

---
 sources/io.h                                  | 6 ++++++
 sources/router.c                              | 5 ++++-
 third_party/machinarium/sources/machinarium.h | 3 +++
 third_party/machinarium/sources/read.c        | 7 +++++++
 4 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/sources/io.h b/sources/io.h
index 9f15c0f3..d9fe5faf 100644
--- a/sources/io.h
+++ b/sources/io.h
@@ -84,6 +84,12 @@ od_io_detach(od_io_t *io)
 	return machine_io_detach(io->io);
 }
 
+static inline int
+od_io_read_active(od_io_t *io)
+{
+	return machine_read_active(io->io);
+}
+
 static inline int
 od_io_read_start(od_io_t *io)
 {
diff --git a/sources/router.c b/sources/router.c
index 297f6a72..b50592b4 100644
--- a/sources/router.c
+++ b/sources/router.c
@@ -330,6 +330,7 @@ od_router_attach(od_router_t *router, od_config_t *config, od_client_t *client)
 	od_client_pool_set(&route->client_pool, client, OD_CLIENT_QUEUE);
 
 	/* get client server from route server pool */
+	bool restart_read = false;
 	od_server_t *server;
 	for (;;)
 	{
@@ -349,6 +350,7 @@ od_router_attach(od_router_t *router, od_config_t *config, od_client_t *client)
 		 * unsubscribe from pending client read events during the time we wait
 		 * for an available server
 		*/
+		restart_read = od_io_read_active(&client->io);
 		od_io_read_stop(&client->io);
 
 		od_route_unlock(route);
@@ -401,7 +403,8 @@ attach:
 		od_io_attach(&server->io);
 
 	/* maybe restore read events subscription */
-	od_io_read_start(&client->io);
+	if (restart_read)
+		od_io_read_start(&client->io);
 
 	return OD_ROUTER_OK;
 }
diff --git a/third_party/machinarium/sources/machinarium.h b/third_party/machinarium/sources/machinarium.h
index 8c31b73a..d747d831 100644
--- a/third_party/machinarium/sources/machinarium.h
+++ b/third_party/machinarium/sources/machinarium.h
@@ -297,6 +297,9 @@ machine_iov_pending(machine_iov_t*);
 
 /* read */
 
+MACHINE_API int
+machine_read_active(machine_io_t*);
+
 MACHINE_API int
 machine_read_start(machine_io_t*, machine_cond_t*);
 
diff --git a/third_party/machinarium/sources/read.c b/third_party/machinarium/sources/read.c
index 11147afa..6fa344c1 100644
--- a/third_party/machinarium/sources/read.c
+++ b/third_party/machinarium/sources/read.c
@@ -182,3 +182,10 @@ machine_read(machine_io_t *obj, size_t size, uint32_t time_ms)
 	}
 	return msg;
 }
+
+MACHINE_API int
+machine_read_active(machine_io_t *obj)
+{
+	mm_io_t *io = mm_cast(mm_io_t*, obj);
+	return io->on_read != NULL;
+}