Fix: Add timeout on notification socket

[lttng-ust.git] / liblttng-ust / lttng-ust-comm.c

diff --git a/liblttng-ust/lttng-ust-comm.c b/liblttng-ust/lttng-ust-comm.c
index 5a4b6bd8693ed5b427f8baf693a903949d025547..1f60f86dcb4c4287b9690b7fcfd974fb960e5ab1 100644 (file)
--- a/liblttng-ust/lttng-ust-comm.c
+++ b/liblttng-ust/lttng-ust-comm.c
@@ -174,6 +174,9 @@ static const char *cmd_name_mapping[] = {
        [ LTTNG_UST_FILTER ] = "Create Filter",
 };
 
+static const char *str_timeout;
+static int got_timeout_env;
+
 extern void lttng_ring_buffer_client_overwrite_init(void);
 extern void lttng_ring_buffer_client_discard_init(void);
 extern void lttng_ring_buffer_metadata_client_init(void);
@@ -240,6 +243,66 @@ int setup_local_apps(void)
        return 0;
 }
 
+/*
+ * Get notify_sock timeout, in ms.
+ * -1: don't wait. 0: wait forever. >0: timeout, in ms.
+ */
+static
+long get_timeout(void)
+{
+       long constructor_delay_ms = LTTNG_UST_DEFAULT_CONSTRUCTOR_TIMEOUT_MS;
+
+       if (!got_timeout_env) {
+               str_timeout = getenv("LTTNG_UST_REGISTER_TIMEOUT");
+               got_timeout_env = 1;
+       }
+       if (str_timeout)
+               constructor_delay_ms = strtol(str_timeout, NULL, 10);
+       return constructor_delay_ms;
+}
+
+static
+long get_notify_sock_timeout(void)
+{
+       return get_timeout();
+}
+
+/*
+ * Return values: -1: don't wait. 0: wait forever. 1: timeout wait.
+ */
+static
+int get_constructor_timeout(struct timespec *constructor_timeout)
+{
+       long constructor_delay_ms;
+       int ret;
+
+       constructor_delay_ms = get_timeout();
+
+       switch (constructor_delay_ms) {
+       case -1:/* fall-through */
+       case 0:
+               return constructor_delay_ms;
+       default:
+               break;
+       }
+
+       /*
+        * If we are unable to find the current time, don't wait.
+        */
+       ret = clock_gettime(CLOCK_REALTIME, constructor_timeout);
+       if (ret) {
+               return -1;
+       }
+       constructor_timeout->tv_sec += constructor_delay_ms / 1000UL;
+       constructor_timeout->tv_nsec +=
+               (constructor_delay_ms % 1000UL) * 1000000UL;
+       if (constructor_timeout->tv_nsec >= 1000000000UL) {
+               constructor_timeout->tv_sec++;
+               constructor_timeout->tv_nsec -= 1000000000UL;
+       }
+       return 1;
+}
+
 static
 int register_to_sessiond(int socket, enum ustctl_socket_type type)
 {
@@ -820,6 +883,7 @@ void *ust_listener_thread(void *arg)
        int sock, ret, prev_connect_failed = 0, has_waited = 0;
        int open_sock[2];
        int i;
+       long timeout;
 
        /* Restart trying to connect to the session daemon */
 restart:
@@ -862,6 +926,7 @@ restart:
        }
 
        /* Register */
+       timeout = get_notify_sock_timeout();
        for (i = 0; i < 2; i++) {
                ret = ustcomm_connect_unix_sock(sock_info->sock_path);
                if (ret < 0) {
@@ -877,6 +942,28 @@ restart:
                        goto restart;
                }
                open_sock[i] = ret;
+               if (timeout > 0) {
+                       ret = ustcomm_setsockopt_rcv_timeout(open_sock[i],
+                                       timeout);
+                       if (ret < 0) {
+                               WARN("Error setting socket receive timeout");
+                       }
+                       ret = ustcomm_setsockopt_snd_timeout(open_sock[i],
+                                       timeout);
+                       if (ret < 0) {
+                               WARN("Error setting socket send timeout");
+                       }
+               } else if (timeout == -1) {
+                       ret = fcntl(open_sock[i], F_SETFL, O_NONBLOCK);
+                       if (ret < 0) {
+                               WARN("Error setting socket to non-blocking");
+                       }
+               } else {
+                       if (timeout != 0) {
+                               WARN("Unsuppoorted timeout value %ld",
+                                       timeout);
+                       }
+               }
        }
 
        sock_info->socket = open_sock[0];
@@ -992,46 +1079,6 @@ quit:
        return NULL;
 }
 
-/*
- * Return values: -1: don't wait. 0: wait forever. 1: timeout wait.
- */
-static
-int get_timeout(struct timespec *constructor_timeout)
-{
-       long constructor_delay_ms = LTTNG_UST_DEFAULT_CONSTRUCTOR_TIMEOUT_MS;
-       char *str_delay;
-       int ret;
-
-       str_delay = getenv("LTTNG_UST_REGISTER_TIMEOUT");
-       if (str_delay) {
-               constructor_delay_ms = strtol(str_delay, NULL, 10);
-       }
-
-       switch (constructor_delay_ms) {
-       case -1:/* fall-through */
-       case 0:
-               return constructor_delay_ms;
-       default:
-               break;
-       }
-
-       /*
-        * If we are unable to find the current time, don't wait.
-        */
-       ret = clock_gettime(CLOCK_REALTIME, constructor_timeout);
-       if (ret) {
-               return -1;
-       }
-       constructor_timeout->tv_sec += constructor_delay_ms / 1000UL;
-       constructor_timeout->tv_nsec +=
-               (constructor_delay_ms % 1000UL) * 1000000UL;
-       if (constructor_timeout->tv_nsec >= 1000000000UL) {
-               constructor_timeout->tv_sec++;
-               constructor_timeout->tv_nsec -= 1000000000UL;
-       }
-       return 1;
-}
-
 /*
  * sessiond monitoring thread: monitor presence of global and per-user
  * sessiond by polling the application common named pipe.
@@ -1069,7 +1116,7 @@ void __attribute__((constructor)) lttng_ust_init(void)
        lttng_ring_buffer_client_overwrite_init();
        lttng_ring_buffer_client_discard_init();
 
-       timeout_mode = get_timeout(&constructor_timeout);
+       timeout_mode = get_constructor_timeout(&constructor_timeout);
 
        ret = sem_init(&constructor_wait, 0, 0);
        assert(!ret);