write_graphite plugin: Improved error reporting when connecting to the server.

[collectd.git] / src / write_graphite.c

diff --git a/src/write_graphite.c b/src/write_graphite.c
index 949a842..392d570 100644 (file)
--- a/src/write_graphite.c
+++ b/src/write_graphite.c
@@ -174,6 +174,8 @@ static int wg_callback_init (struct wg_callback *cb)
     const char *node = cb->node ? cb->node : WG_DEFAULT_NODE;
     const char *service = cb->service ? cb->service : WG_DEFAULT_SERVICE;
 
+    char connerr[1024] = "";
+
     if (cb->sock_fd > 0)
         return (0);
 
@@ -199,12 +201,19 @@ static int wg_callback_init (struct wg_callback *cb)
     {
         cb->sock_fd = socket (ai_ptr->ai_family, ai_ptr->ai_socktype,
                 ai_ptr->ai_protocol);
-        if (cb->sock_fd < 0)
+        if (cb->sock_fd < 0) {
+            char errbuf[1024];
+            snprintf (connerr, sizeof (connerr), "failed to open socket: %s",
+                    sstrerror (errno, errbuf, sizeof (errbuf)));
             continue;
+        }
 
         status = connect (cb->sock_fd, ai_ptr->ai_addr, ai_ptr->ai_addrlen);
         if (status != 0)
         {
+            char errbuf[1024];
+            snprintf (connerr, sizeof (connerr), "failed to connect to remote "
+                    "host: %s", sstrerror (errno, errbuf, sizeof (errbuf)));
             close (cb->sock_fd);
             cb->sock_fd = -1;
             continue;
@@ -217,12 +226,12 @@ static int wg_callback_init (struct wg_callback *cb)
 
     if (cb->sock_fd < 0)
     {
-        char errbuf[1024];
+        if (connerr[0] == '\0')
+            /* this should not happen but try to get a message anyway */
+            sstrerror (errno, connerr, sizeof (connerr));
         c_complain (LOG_ERR, &cb->init_complaint,
                 "write_graphite plugin: Connecting to %s:%s failed. "
-                "The last error was: %s", node, service,
-                sstrerror (errno, errbuf, sizeof (errbuf)));
-        close (cb->sock_fd);
+                "The last error was: %s", node, service, connerr);
         return (-1);
     }
     else
@@ -250,8 +259,11 @@ static void wg_callback_free (void *data)
 
     wg_flush_nolock (/* timeout = */ 0, cb);
 
-    close(cb->sock_fd);
-    cb->sock_fd = -1;
+    if (cb->sock_fd >= 0)
+    {
+        close (cb->sock_fd);
+        cb->sock_fd = -1;
+    }
 
     sfree(cb->name);
     sfree(cb->node);
@@ -367,12 +379,9 @@ static int wg_write_messages (const data_set_t *ds, const value_list_t *vl,
         return (status);
 
     /* Send the message to graphite */
-    wg_send_message (buffer, cb);
-    if (status != 0)
-    {
-        /* An error message has already been printed. */
+    status = wg_send_message (buffer, cb);
+    if (status != 0) /* error message has been printed already. */
         return (status);
-    }
 
     return (0);
 } /* int wg_write_messages */