[PATCH] don't try to clean up listening sockets twice prior to exec

[Jeff Trawick]

I'm not seeing any "close(-1)" calls on a trace of a mod_cgid-invoked 
script anymore now.

old trace (in the new script child prior to exec):

5108:   close(4)                                        = 0
5108:   close(3)                                        = 0
5108:   close(-1)                                       Err#9 EBADF
5108:   close(-1)                                       Err#9 EBADF
5108:   close(9)                                        = 0
5108:   close(6)                                        = 0
5108:   close(8)                                        = 0
5108:   close(7)                                        = 0
5108:   close(13)                                       = 0
5108:   fcntl(12, F_DUP2FD, 0x00000000)                 = 0
5108:   close(12)                                       = 0
5108:   close(14)                                       = 0
5108:   fcntl(15, F_DUP2FD, 0x00000001)                 = 1
5108:   close(15)                                       = 0
5108:   close(16)                                       = 0
5108:   fcntl(17, F_DUP2FD, 0x00000002)                 = 2
5108:   close(17)                                       = 0
5108:   sigaction(SIGCLD, 0xFFBEF5C8, 0xFFBEF6D0)       = 0
5108:   chdir("/export/home/trawick/apacheinst/cgi-bin/") = 0
new trace:

6616:   close(4)                                        = 0
6616:   close(3)                                        = 0
6616:   close(9)                                        = 0
6616:   close(6)                                        = 0
6616:   close(8)                                        = 0
6616:   close(7)                                        = 0
6616:   close(13)                                       = 0
6616:   fcntl(12, F_DUP2FD, 0x00000000)                 = 0
6616:   close(12)                                       = 0
6616:   close(14)                                       = 0
6616:   fcntl(15, F_DUP2FD, 0x00000001)                 = 1
6616:   close(15)                                       = 0
6616:   close(16)                                       = 0
6616:   fcntl(17, F_DUP2FD, 0x00000002)                 = 2
6616:   close(17)                                       = 0
6616:   sigaction(SIGCLD, 0xFFBEF5C8, 0xFFBEF6D0)       = 0
6616:   chdir("/export/home/trawick/apacheinst/cgi-bin/") = 0
I'd been seeing these bogus closes for eons, but thought they were 
associated with pipes until I stepped through the cleanup-for-exec path 
early this a.m..

Index: server/listen.c
===================================================================
RCS file: /home/cvs/httpd-2.0/server/listen.c,v
retrieving revision 1.83.2.2
diff -u -r1.83.2.2 listen.c
--- server/listen.c     3 Feb 2003 17:32:00 -0000       1.83.2.2
+++ server/listen.c     30 Mar 2003 16:55:24 -0000
@@ -340,6 +340,8 @@
     ap_listen_rec *lr;
     ap_listen_rec *next;
     int num_open;
+    const char *userdata_key = "ap_listen_open";
+    void *data;
 
     /* Don't allocate a default listener.  If we need to listen to a
      * port, then the user needs to have a Listen directive in their
@@ -370,8 +372,17 @@
     }
     old_listeners = NULL;
 
-    apr_pool_cleanup_register(pool, NULL, apr_pool_cleanup_null,
-                              close_listeners_on_exec);
+    /* we come through here on both passes of the open logs phase
+     * only register the cleanup once... otherwise we try to close
+     * listening sockets twice when cleaning up prior to exec
+     */
+    apr_pool_userdata_get(&data, userdata_key, pool);
+    if (!data) {
+        apr_pool_userdata_set((const void *)1, userdata_key,
+                              apr_pool_cleanup_null, pool);
+        apr_pool_cleanup_register(pool, NULL, apr_pool_cleanup_null,
+                                  close_listeners_on_exec);
+    }
 
     return num_open ? 0 : -1;
 }