ping plugin: Let start_thread() return gracefully when thread is already running.

Signaling an error caused the init function to signal an error, causing
the read callback to be unregistered on systems where init is called
more than once.

Fixes: #869

diff --git a/src/ping.c b/src/ping.c
index ecbbd9d..fca730f 100644 (file)
--- a/src/ping.c
+++ b/src/ping.c
@@ -374,7 +374,7 @@ static int start_thread (void) /* {{{ */
   if (ping_thread_loop != 0)
   {
     pthread_mutex_unlock (&ping_lock);
-    return (-1);
+    return (0);
   }
 
   ping_thread_loop = 1;
@@ -388,7 +388,7 @@ static int start_thread (void) /* {{{ */
     pthread_mutex_unlock (&ping_lock);
     return (-1);
   }
-    
+
   pthread_mutex_unlock (&ping_lock);
   return (0);
 } /* }}} int start_thread */
@@ -439,10 +439,7 @@ static int ping_init (void) /* {{{ */
         "Will use a timeout of %gs.", ping_timeout);
   }
 
-  if (start_thread () != 0)
-    return (-1);
-
-  return (0);
+  return (start_thread ());
 } /* }}} int ping_init */
 
 static int config_set_string (const char *name, /* {{{ */