exit on signal, compatible with bad versions of libevent.

git-svn-id: file:///svn/unbound/trunk@161 be551aaa-1e26-0410-a405-d3ace91eadb9

configure.ac

@@ -421,6 +421,7 @@ if test x_$withval != x_no; then
 	AC_SEARCH_LIBS(event_set, [event])
 	AC_CHECK_HEADERS([event.h],,, [AC_INCLUDES_DEFAULT])
 	AC_CHECK_FUNCS([event_base_free]) # only in libevent 1.2 and later
+	AC_CHECK_FUNCS([event_base_once]) # only in libevent 1.4? and later
 else
 	AC_DEFINE(USE_MINI_EVENT, 1, [Define if you want to use internal select based events])
 fi
@@ -519,6 +520,10 @@ AH_BOTTOM([
 #define fseeko fseek
 #define ftello ftell
 #endif /* HAVE_FSEEKO */
+#if defined(HAVE_EVENT_H) && !defined(HAVE_EVENT_BASE_ONCE) && (defined(HAVE_PTHREAD) || defined(HAVE_SOLARIS_THREADS))
+   /* using version of libevent that is not threadsafe. */
+#  define LIBEVENT_SIGNAL_PROBLEM 1
+#endif
 
 #ifndef RAND_MAX
 #define RAND_MAX	2147483647

daemon/daemon.c

@@ -59,6 +59,9 @@ static int sig_record_reload = 0;
   * when multiple signals in quick succession are sent to us. */
 static RETSIGTYPE record_sigh(int sig)
 {
+#ifdef LIBEVENT_SIGNAL_PROBLEM
+	exit(0);
+#endif 
 	switch(sig)
 	{
 		case SIGTERM:

daemon/worker.c

@@ -323,6 +323,7 @@ worker_init(struct worker* worker, struct config_file *cfg,
 		ub_thread_sig_unblock(SIGINT);
 		ub_thread_sig_unblock(SIGQUIT);
 		ub_thread_sig_unblock(SIGTERM);
+#ifndef LIBEVENT_SIGNAL_PROBLEM
 		worker->comsig = comm_signal_create(worker->base, 
 			worker_sighandler, worker);
 		if(!worker->comsig || !comm_signal_bind(worker->comsig, SIGHUP)
@@ -333,6 +334,7 @@ worker_init(struct worker* worker, struct config_file *cfg,
 			worker_delete(worker);
 			return 0;
 		}
+#endif /* LIBEVENT_SIGNAL_PROBLEM */
 	} else { /* !do_sigs */
 		worker->comsig = 0;
 	}

doc/Changelog

@@ -2,6 +2,9 @@
 	- do not compile fork funcs unless needed. Otherwise will give
 	  type errors as their typedefs have not been enabled.
 	- log shows thread numbers much more nicely (and portably).
+	- even on systems with nonthreadsafe libevent signal handling,
+	  unbound will exit if given a signal.
+	  Reloads will not work, and exit is not graceful.
 
 1 March 2007: Wouter
 	- Signals, libevent and threads work well, with libevent patch and

doc/README

@@ -18,4 +18,11 @@ This software is under BSD license, see LICENSE for details.
   * run libtoolize -c if config.sub is missing.
   * autoreconf (autoheader && autoconf), if ./configure is missing.
 
+Known issues
+------------
+o If libevent is older (1.3 and before), unbound will exit instead of reload
+  on sighup. On a restart 'did not exit gracefully last time' warning is 
+  printed. Perform ./configure --with-libevent=no or update libevent, rerun 
+  configure and recompile unbound to make sighup work correctly.
+
 * mailto:wouter@nlnetlabs.nl