Trunk r1406690:

apr_socket_accept_filter: Return success when trying to again set the filter
                          to the same value as before.

                          Use apr_cpystrn().

PR: 37863     (warning message from Apache httpd during restart)


git-svn-id: http://svn.apache.org/repos/asf/apr/apr/branches/1.4.x@1406694 13f79535-47bb-0310-9956-ffa450edef68

2 files changed, 23 insertions, 2 deletions

diff --git a/CHANGES b/CHANGES
index a1781b02e..cd111da1f 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,6 +1,10 @@
                                                      -*- coding: utf-8 -*-
 Changes for APR 1.4.7
 
+  *) apr_socket_accept_filter: Return success when trying to again set
+     the filter to the same value as before, avoiding an unhelpful
+     APR_EINVAL.  PR 37863.  [Jeff Trawick]
+
   *) configure: Fix Linux 3.x detection. PR 54001. [Gilles Espinasse
      <g esp free fr>]
 
diff --git a/network_io/unix/sockopt.c b/network_io/unix/sockopt.c
index 546f4a3fa..7b67c2ec1 100644
--- a/network_io/unix/sockopt.c
+++ b/network_io/unix/sockopt.c
@@ -389,8 +389,25 @@ apr_status_t apr_socket_accept_filter(apr_socket_t *sock, char *nonconst_name,
     const char *args = nonconst_args;
 
     struct accept_filter_arg af;
-    strncpy(af.af_name, name, 16);
-    strncpy(af.af_arg, args, 256 - 16);
+    socklen_t optlen = sizeof(af);
+
+    /* FreeBSD returns an error if the filter is already set; ignore
+     * this call if we previously set it to the same value.
+     */
+    if ((getsockopt(sock->socketdes, SOL_SOCKET, SO_ACCEPTFILTER,
+                    &af, &optlen)) == 0) {
+        if (!strcmp(name, af.af_name) && !strcmp(args, af.af_arg)) {
+            return APR_SUCCESS;
+        }
+    }
+
+    /* Uhh, at least in FreeBSD 9 the fields are declared as arrays of
+     * these lengths; did sizeof not work in some ancient release?
+     *
+     * FreeBSD kernel sets the last byte to a '\0'.
+     */
+    apr_cpystrn(af.af_name, name, 16);
+    apr_cpystrn(af.af_arg, args, 256 - 16);
 
     if ((setsockopt(sock->socketdes, SOL_SOCKET, SO_ACCEPTFILTER,
           &af, sizeof(af))) < 0) {