rrd_client: Improved error handling / reporting.

[rrdtool.git] / src / rrd_client.c

diff --git a/src/rrd_client.c b/src/rrd_client.c
index 7fa9817..287f642 100644 (file)
--- a/src/rrd_client.c
+++ b/src/rrd_client.c
@@ -17,6 +17,7 @@
  *
  * Authors:
  *   Florian octo Forster <octo at verplant.org>
+ *   Sebastian tokkee Harl <sh at tokkee.org>
  **/
 
 #include "rrd.h"
@@ -51,6 +52,45 @@ static int sd = -1;
 static FILE *sh = NULL;
 static char *sd_path = NULL; /* cache the path for sd */
 
+/* get_path: Return a path name appropriate to be sent to the daemon.
+ *
+ * When talking to a local daemon (thru a UNIX socket), relative path names
+ * are resolved to absolute path names to allow for transparent integration
+ * into existing solutions (as requested by Tobi). Else, absolute path names
+ * are not allowed, since path name translation is done by the server.
+ *
+ * One must hold `lock' when calling this function. */
+static const char *get_path (const char *path, char *resolved_path) /* {{{ */
+{
+  const char *ret = path;
+  int is_unix = 0;
+
+  if ((*sd_path == '/')
+      || (strncmp ("unix:", sd_path, strlen ("unix:")) == 0))
+    is_unix = 1;
+
+  if (*path == '/') /* absolute path */
+  {
+    if (! is_unix)
+    {
+      rrd_set_error ("absolute path names not allowed when talking "
+          "to a remote daemon");
+      return (NULL);
+    }
+    /* else: nothing to do */
+  }
+  else /* relative path */
+  {
+    if (is_unix)
+    {
+      realpath (path, resolved_path);
+      ret = resolved_path;
+    }
+    /* else: nothing to do */
+  }
+  return (ret);
+} /* }}} char *get_path */
+
 /* One must hold `lock' when calling `close_connection'. */
 static void close_connection (void) /* {{{ */
 {
@@ -212,6 +252,8 @@ static int response_read (rrdc_response_t **ret_response) /* {{{ */
 
   if (ret->status <= 0)
   {
+    if (ret->status < 0)
+      rrd_set_error("rrdcached: %s", ret->message);
     *ret_response = ret;
     return (0);
   }
@@ -253,19 +295,15 @@ static int request (const char *buffer, size_t buffer_size, /* {{{ */
   int status;
   rrdc_response_t *res;
 
-  pthread_mutex_lock (&lock);
-
   if (sh == NULL)
-  {
-    pthread_mutex_unlock (&lock);
     return (ENOTCONN);
-  }
 
   status = (int) fwrite (buffer, buffer_size, /* nmemb = */ 1, sh);
   if (status != 1)
   {
     close_connection ();
-    pthread_mutex_unlock (&lock);
+    rrd_set_error("request: socket error (%d) while talking to rrdcached",
+                  status);
     return (-1);
   }
   fflush (sh);
@@ -273,10 +311,12 @@ static int request (const char *buffer, size_t buffer_size, /* {{{ */
   res = NULL;
   status = response_read (&res);
 
-  pthread_mutex_unlock (&lock);
-
   if (status != 0)
+  {
+    if (status < 0)
+      rrd_set_error("request: internal error while talking to rrdcached");
     return (status);
+  }
 
   *ret_response = res;
   return (0);
@@ -412,7 +452,12 @@ static int rrdc_connect_network (const char *addr_orig) /* {{{ */
                         port == NULL ? RRDCACHED_DEFAULT_PORT : port,
                         &ai_hints, &ai_res);
   if (status != 0)
-    return (status);
+  {
+    rrd_set_error ("failed to resolve address `%s' (port %s): %s",
+        addr, port == NULL ? RRDCACHED_DEFAULT_PORT : port,
+        gai_strerror (status));
+    return (-1);
+  }
 
   for (ai_ptr = ai_res; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
   {
@@ -470,6 +515,7 @@ int rrdc_connect (const char *addr) /* {{{ */
     close_connection();
   }
 
+  rrd_clear_error ();
   if (strncmp ("unix:", addr, strlen ("unix:")) == 0)
     status = rrdc_connect_unix (addr + strlen ("unix:"));
   else if (addr[0] == '/')
@@ -480,10 +526,18 @@ int rrdc_connect (const char *addr) /* {{{ */
   if (status == 0 && sd >= 0)
     sd_path = strdup(addr);
   else
+  {
+    char *err = rrd_test_error () ? rrd_get_error () : "Internal error";
+    /* err points the string that gets written to by rrd_set_error(), thus we
+     * cannot pass it to that function */
+    err = strdup (err);
     rrd_set_error("Unable to connect to rrdcached: %s",
                   (status < 0)
-                  ? "Internal error"
+                  ? (err ? err : "Internal error")
                   : rrd_strerror (status));
+    if (err != NULL)
+      free (err);
+  }
 
   pthread_mutex_unlock (&lock);
   return (status);
@@ -510,6 +564,7 @@ int rrdc_update (const char *filename, int values_num, /* {{{ */
   rrdc_response_t *res;
   int status;
   int i;
+  char file_path[PATH_MAX];
 
   memset (buffer, 0, sizeof (buffer));
   buffer_ptr = &buffer[0];
@@ -519,15 +574,29 @@ int rrdc_update (const char *filename, int values_num, /* {{{ */
   if (status != 0)
     return (ENOBUFS);
 
+  pthread_mutex_lock (&lock);
+  filename = get_path (filename, file_path);
+  if (filename == NULL)
+  {
+    pthread_mutex_unlock (&lock);
+    return (-1);
+  }
+
   status = buffer_add_string (filename, &buffer_ptr, &buffer_free);
   if (status != 0)
+  {
+    pthread_mutex_unlock (&lock);
     return (ENOBUFS);
+  }
 
   for (i = 0; i < values_num; i++)
   {
     status = buffer_add_value (values[i], &buffer_ptr, &buffer_free);
     if (status != 0)
+    {
+      pthread_mutex_unlock (&lock);
       return (ENOBUFS);
+    }
   }
 
   assert (buffer_free < sizeof (buffer));
@@ -537,6 +606,8 @@ int rrdc_update (const char *filename, int values_num, /* {{{ */
 
   res = NULL;
   status = request (buffer, buffer_size, &res);
+  pthread_mutex_unlock (&lock);
+
   if (status != 0)
     return (status);
 
@@ -554,6 +625,7 @@ int rrdc_flush (const char *filename) /* {{{ */
   size_t buffer_size;
   rrdc_response_t *res;
   int status;
+  char file_path[PATH_MAX];
 
   if (filename == NULL)
     return (-1);
@@ -566,9 +638,20 @@ int rrdc_flush (const char *filename) /* {{{ */
   if (status != 0)
     return (ENOBUFS);
 
+  pthread_mutex_lock (&lock);
+  filename = get_path (filename, file_path);
+  if (filename == NULL)
+  {
+    pthread_mutex_unlock (&lock);
+    return (-1);
+  }
+
   status = buffer_add_string (filename, &buffer_ptr, &buffer_free);
   if (status != 0)
+  {
+    pthread_mutex_unlock (&lock);
     return (ENOBUFS);
+  }
 
   assert (buffer_free < sizeof (buffer));
   buffer_size = sizeof (buffer) - buffer_free;
@@ -577,6 +660,8 @@ int rrdc_flush (const char *filename) /* {{{ */
 
   res = NULL;
   status = request (buffer, buffer_size, &res);
+  pthread_mutex_unlock (&lock);
+
   if (status != 0)
     return (status);
 
@@ -598,13 +683,23 @@ int rrdc_flush_if_daemon (const char *opt_daemon, const char *filename) /* {{{ *
 
   if (rrdc_is_connected(opt_daemon))
   {
+    rrd_clear_error();
     status = rrdc_flush (filename);
-    if (status != 0)
+
+    if (status != 0 && !rrd_test_error())
     {
-      rrd_set_error ("rrdc_flush (%s) failed with status %i.",
-                     filename, status);
+      if (status > 0)
+      {
+        rrd_set_error("rrdc_flush (%s) failed: %s",
+                      filename, rrd_strerror(status));
+      }
+      else if (status < 0)
+      {
+        rrd_set_error("rrdc_flush (%s) failed with status %i.",
+                      filename, status);
+      }
     }
-  } /* if (daemon_addr) */
+  } /* if (rrdc_is_connected(..)) */
 
   return status;
 } /* }}} int rrdc_flush_if_daemon */
@@ -631,7 +726,10 @@ int rrdc_stats_get (rrdc_stats_t **ret_stats) /* {{{ */
    * }}} */
 
   res = NULL;
+  pthread_mutex_lock (&lock);
   status = request ("STATS\n", strlen ("STATS\n"), &res);
+  pthread_mutex_unlock (&lock);
+
   if (status != 0)
     return (status);
 
@@ -733,7 +831,7 @@ void rrdc_stats_free (rrdc_stats_t *ret_stats) /* {{{ */
 
     if (this->name != NULL)
     {
-      free (this->name);
+      free ((char *)this->name);
       this->name = NULL;
     }
     free (this);