r7411@Kushana: nickm | 2006-08-17 19:00:25 -0400

patch suggested by Karsten Loesing: respond to SIGNAL command before we execute the signal, in case the signal shuts us down.


svn:r7072

src/or/control.c

@@ -1152,15 +1152,17 @@ handle_control_signal(control_connection_t *conn, uint32_t len,
     if (sig<0)
       return 0;
   }
-
-  if (control_signal_act(sig) < 0) {
+  
+  if (!control_signal_check(sig)) {
     if (STATE_IS_V0(conn->_base.state))
       send_control0_error(conn, ERR_SYNTAX, "Unrecognized signal number.");
     else
-      connection_write_str_to_buf("551 Internal error acting on signal\r\n",
+      connection_write_str_to_buf("551 Unable to act on signal\r\n",
                                   conn);
   } else {
+    /* Send DONE first, in case the signal makes us shut down. */
     send_control_done(conn);
+    control_signal_act(sig);
   }
   return 0;
 }

src/or/main.c

@@ -1196,16 +1196,33 @@ do_main_loop(void)
   }
 }
 
+/* DOCDOC */
+int
+control_signal_check(int the_signal)
+{
+  switch (the_signal)
+    {
+    case 1:
+    case 2:
+    case 10:
+    case 12:
+    case 15:
+    case SIGNEWNYM:
+      return 1;
+    default:
+      return 0;
+    }
+}
+
 /** Used to implement the SIGNAL control command: if we accept
- * <b>the_signal</b> as a remote pseudo-signal, then act on it and
- * return 0.  Else return -1. */
+ * <b>the_signal</b> as a remote pseudo-signal, act on it. */
 /* We don't re-use catch() here because:
  *   1. We handle a different set of signals than those allowed in catch.
  *   2. Platforms without signal() are unlikely to define SIGfoo.
  *   3. The control spec is defined to use fixed numeric signal values
  *      which just happen to match the unix values.
  */
-int
+void
 control_signal_act(int the_signal)
 {
   switch (the_signal)
@@ -1229,9 +1246,9 @@ control_signal_act(int the_signal)
       signal_callback(0,0,(void*)(uintptr_t)SIGNEWNYM);
       break;
     default:
-      return -1;
+      log_warn(LD_BUG, "Unrecognized signal number %d.", the_signal);
+      break;
     }
-  return 0;
 }
 
 /** Libevent callback: invoked when we get a signal.

src/or/or.h

@@ -2174,7 +2174,8 @@ void connection_start_writing(connection_t *conn);
 void directory_all_unreachable(time_t now);
 void directory_info_has_arrived(time_t now, int from_cache);
 
-int control_signal_act(int the_signal);
+int control_signal_check(int the_signal);
+void control_signal_act(int the_signal);
 void handle_signals(int is_parent);
 void tor_cleanup(void);
 void tor_free_all(int postfork);