#196535 by sun, chx, dww: check whether Drupal can issue HTTP requests at all, so we know that this is the cause of problems, not the remote host not responding.

2 files changed, 19 insertions, 2 deletions

diff --git a/includes/common.inc b/includes/common.inc
index 82de30b39..ecbc3dfff 100644
--- a/includes/common.inc
+++ b/includes/common.inc
@@ -415,7 +415,23 @@ function drupal_access_denied() {
  *   data and redirect status.
  */
 function drupal_http_request($url, $headers = array(), $method = 'GET', $data = NULL, $retry = 3) {
+  static $self_test = FALSE;
   $result = new stdClass();
+  // Try to clear the drupal_http_request_fails variable if it's set. We
+  // can't tie this call to any error because there is no surefire way to
+  // tell whether a request has failed, so we add the check to places where
+  // some parsing has failed.
+  if (!$self_test && variable_get('drupal_http_request_fails', FALSE)) {
+    $self_test = TRUE;
+    $works = module_invoke('system', 'check_http_request');
+    $self_test = FALSE;
+    if (!$works) {
+      // Do not bother with further operations if we already know that we
+      // have no chance.
+      $result->error = t("The server can't issue HTTP requests");
+      return $result;
+    }
+  }
 
   // Parse the URL and make sure we can handle the schema.
   $uri = parse_url($url);
@@ -439,8 +455,8 @@ function drupal_http_request($url, $headers = array(), $method = 'GET', $data =
 
   // Make sure the socket opened properly.
   if (!$fp) {
-    // When a network error occurs, we make sure that it is a negative number so
-    // it can clash with the HTTP status codes.
+    // When a network error occurs, we use a negative number so it does not
+    // clash with the HTTP status codes.
     $result->code = -$errno;
     $result->error = trim($errstr);
     return $result;
diff --git a/includes/xmlrpc.inc b/includes/xmlrpc.inc
index ebd19c461..6dd79b8c3 100644
--- a/includes/xmlrpc.inc
+++ b/includes/xmlrpc.inc
@@ -350,6 +350,7 @@ function xmlrpc_error($code = NULL, $message = NULL) {
     $xmlrpc_error->is_error = TRUE;
     $xmlrpc_error->code = $code;
     $xmlrpc_error->message = $message;
+    module_invoke('system', 'check_http_request');
   }
   return $xmlrpc_error;
 }