fixed a potential problem with wins_write_database() child processes.

In sig_term() we were calling wins_write_database(0) which would fork a
child. This child might then get killed by the same process killing
off the parent. That process would then fork another child etc.

The solution is to pass a "background" flag to wins_write_database(0)
and only fork if this is set.
(This used to be commit 1e1a512e3ff59f962fb3de382f671618bed60839)

4 files changed, 14 insertions, 19 deletions

diff --git a/source3/include/proto.h b/source3/include/proto.h
index a864cd7033..f2b74b4076 100644
--- a/source3/include/proto.h
+++ b/source3/include/proto.h
@@ -825,7 +825,7 @@ void wins_process_name_query_request(struct subnet_record *subrec,
 void wins_process_name_release_request(struct subnet_record *subrec,
                                        struct packet_struct *p);
 void initiate_wins_processing(time_t t);
-void wins_write_database(void);
+void wins_write_database(BOOL background);
 
 /*The following definitions come from  nmbd/nmbd_workgroupdb.c  */
 
@@ -1744,11 +1744,6 @@ void file_chain_reset(void);
 void file_chain_save(void);
 void file_chain_restore(void);
 
-/*The following definitions come from  smbd/groupname.c  */
-
-void load_groupname_map(void);
-void map_gid_to_sid( gid_t gid, DOM_SID *psid);
-
 /*The following definitions come from  smbd/ipc.c  */
 
 int reply_trans(connection_struct *conn, char *inbuf,char *outbuf, int size, int bufsize);
diff --git a/source3/nmbd/nmbd.c b/source3/nmbd/nmbd.c
index 482e136ba4..d7383fb736 100644
--- a/source3/nmbd/nmbd.c
+++ b/source3/nmbd/nmbd.c
@@ -68,7 +68,7 @@ static void sig_term(int sig)
   DEBUG(0,("Got SIGTERM: going down...\n"));
   
   /* Write out wins.dat file if samba is a WINS server */
-  wins_write_database();
+  wins_write_database(False);
   
   /* Remove all SELF registered names. */
   release_my_names();
diff --git a/source3/nmbd/nmbd_serverlistdb.c b/source3/nmbd/nmbd_serverlistdb.c
index a4dab6f419..458fbd0085 100644
--- a/source3/nmbd/nmbd_serverlistdb.c
+++ b/source3/nmbd/nmbd_serverlistdb.c
@@ -321,6 +321,8 @@ void write_browse_list(time_t t, BOOL force_write)
       return;
   }
 
+  lasttime = t;
+
   dump_workgroups(force_write);
  
   for (subrec = FIRST_SUBNET; subrec ; subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec))
@@ -335,7 +337,6 @@ void write_browse_list(time_t t, BOOL force_write)
   if(!list_changed)
     return;
 
-  lasttime = t;
   updatecount++;
     
   pstrcpy(fname,lp_lockdir());
diff --git a/source3/nmbd/nmbd_winsserver.c b/source3/nmbd/nmbd_winsserver.c
index 1502dd8155..3c831ee1ea 100644
--- a/source3/nmbd/nmbd_winsserver.c
+++ b/source3/nmbd/nmbd_winsserver.c
@@ -1535,7 +1535,7 @@ void initiate_wins_processing(time_t t)
   expire_names_on_subnet(wins_server_subnet, t);
 
   if(wins_server_subnet->namelist_changed)
-    wins_write_database();
+    wins_write_database(True);
 
   wins_server_subnet->namelist_changed = False;
 }
@@ -1543,7 +1543,7 @@ void initiate_wins_processing(time_t t)
 /*******************************************************************
  Write out the current WINS database.
 ******************************************************************/
-void wins_write_database(void)
+void wins_write_database(BOOL background)
 {
   struct name_record *namerec;
   pstring fname, fnamenew;
@@ -1556,16 +1556,15 @@ void wins_write_database(void)
 
   /* we will do the writing in a child process to ensure that the parent
      doesn't block while this is done */
-  if ((child_pid=fork())) {
-	  return;
+  if (background) {
+	  CatchChild();
+	  if ((child_pid=fork())) {
+		  return;
+	  }
   }
 
-  pstrcpy(fname,lp_lockdir());
-  trim_string(fname,NULL,"/");
-  pstrcat(fname,"/");
-  pstrcat(fname,WINS_LIST);
-  pstrcpy(fnamenew,fname);
-  pstrcat(fnamenew,".");
+  slprintf(fname,sizeof(fname),"%s/%s.%d", lp_lockdir(), WINS_LIST, getpid());
+  string_sub(s->fname,"//", "/");
 
   if((fp = fopen(fnamenew,"w")) == NULL)
   {
@@ -1612,7 +1611,7 @@ void wins_write_database(void)
   }
   
   fclose(fp);
-  unlink(fname);
   chmod(fnamenew,0644);
+  unlink(fname);
   rename(fnamenew,fname);
 }