2004-07-14 Paul Jakma <paul@dishone.st>

        * sigevent.c: (quagga_signal_handler) add a global caught flag, set
          the flags to a constant rather increment to be kinder.
          (quagga_sigevent_process) new function, to do core of what
          quagga_signal_timer did. dont block signals at all as sig->caught
          is volatile sig_atomic_t and should be safe to access from signal
          and normal contexts. The signal blocking is unneeded paranoia, but
          is left intact under an ifdef, should some platform require it.
          Check global caught flag before iterating through array.
          (quagga_signal_timer) nearly everything moved to
          quagga_sigevent_process. Left in under ifdef, in case some
          platform could use a regular timer check for signals.
        * sigevent.h: quagga_sigevent_process declaration.
        * thread.c: (thread_fetch) check for signals at beginning of
          scheduler loop, check for signals if select returns EINTR.
diff --git a/lib/thread.c b/lib/thread.c
index 93809f2..2e953c5 100644
--- a/lib/thread.c
+++ b/lib/thread.c
@@ -28,6 +28,7 @@
 #include "log.h"
 #include "hash.h"
 #include "command.h"
+#include "sigevent.h"
 
 static struct hash *cpu_record = NULL;
 
@@ -748,23 +749,26 @@
 
   while (1)
     {
-      /* Normal event is the highest priority.  */
+      /* Signals are highest priority */
+      quagga_sigevent_process ();
+       
+      /* Normal event are the next highest priority.  */
       if ((thread = thread_trim_head (&m->event)) != NULL)
-	return thread_run (m, thread, fetch);
+        return thread_run (m, thread, fetch);
 
       /* Execute timer.  */
       gettimeofday (&timer_now, NULL);
 
       for (thread = m->timer.head; thread; thread = thread->next)
-	if (timeval_cmp (timer_now, thread->u.sands) >= 0)
-	  {
-	    thread_list_delete (&m->timer, thread);
-	    return thread_run (m, thread, fetch);
-	  }
+        if (timeval_cmp (timer_now, thread->u.sands) >= 0)
+          {
+            thread_list_delete (&m->timer, thread);
+            return thread_run (m, thread, fetch);
+          }
 
       /* If there are any ready threads, process top of them.  */
       if ((thread = thread_trim_head (&m->ready)) != NULL)
-	return thread_run (m, thread, fetch);
+        return thread_run (m, thread, fetch);
 
       /* Structure copy.  */
       readfd = m->readfd;
@@ -777,16 +781,20 @@
       num = select (FD_SETSIZE, &readfd, &writefd, &exceptfd, timer_wait);
 
       if (num == 0)
-	continue;
+        continue;
 
       if (num < 0)
-	{
-	  if (errno == EINTR)
-	    continue;
+        {
+          if (errno == EINTR)
+            {
+              /* signal received */
+              quagga_sigevent_process ();
+              continue;
+            }
 
-	  zlog_warn ("select() error: %s", strerror (errno));
-	  return NULL;
-	}
+          zlog_warn ("select() error: %s", strerror (errno));
+            return NULL;
+        }
 
       /* Normal priority read thead. */
       ready = thread_process_fd (m, &m->read, &readfd, &m->readfd);
@@ -795,7 +803,7 @@
       ready = thread_process_fd (m, &m->write, &writefd, &m->writefd);
 
       if ((thread = thread_trim_head (&m->ready)) != NULL)
-	return thread_run (m, thread, fetch);
+        return thread_run (m, thread, fetch);
     }
 }