* Bugfix for above

[citadel.git] / citadel / serv_network.c

diff --git a/citadel/serv_network.c b/citadel/serv_network.c
index fa1c7d1e7897f00f669708369eeed2bd7cad65df..114eed6f1f12f361b4dd56bcb02f8566f643dfb9 100644 (file)
--- a/citadel/serv_network.c
+++ b/citadel/serv_network.c
@@ -7,6 +7,13 @@
  * Copyright (C) 2000-2002 by Art Cancro and others.
  * This code is released under the terms of the GNU General Public License.
  *
+ * ** NOTE **   A word on the S_NETCONFIGS semaphore:
+ * This is a fairly high-level type of critical section.  It ensures that no
+ * two threads work on the netconfigs files at the same time.  Since we do
+ * so many things inside these, here are the rules:
+ *  1. begin_critical_section(S_NETCONFIGS) *before* begin_ any others.
+ *  2. Do *not* perform any I/O with the client during these sections.
+ *
  */
 
 /*
@@ -372,7 +379,9 @@ void cmd_snet(char *argbuf) {
         */
        unlink(filename);
        snprintf(buf, sizeof buf, "/bin/mv %s %s", tempfilename, filename);
+       begin_critical_section(S_NETCONFIGS);
        system(buf);
+       end_critical_section(S_NETCONFIGS);
 }
 
 
@@ -688,10 +697,14 @@ void network_spoolout_room(char *room_to_spool) {
        memset(&sc, 0, sizeof(struct SpoolControl));
        assoc_file_name(filename, sizeof filename, &CC->quickroom, "netconfigs");
 
+       begin_critical_section(S_NETCONFIGS);
+       end_critical_section(S_NETCONFIGS);
+
        fp = fopen(filename, "r");
        if (fp == NULL) {
                lprintf(7, "Outbound batch processing skipped for <%s>\n",
                        CC->quickroom.QRname);
+               end_critical_section(S_NETCONFIGS);
                return;
        }
 
@@ -792,11 +805,14 @@ void network_spoolout_room(char *room_to_spool) {
                        phree(sc.ignet_push_shares);
                        sc.ignet_push_shares = nptr;
                }
-               fwrite(sc.misc, strlen(sc.misc), 1, fp);
+               if (sc.misc != NULL) {
+                       fwrite(sc.misc, strlen(sc.misc), 1, fp);
+               }
                phree(sc.misc);
 
                fclose(fp);
        }
+       end_critical_section(S_NETCONFIGS);
 
        lprintf(5, "Outbound batch processing finished for <%s>\n",
                CC->quickroom.QRname);