add prepare watcher

[software/libev.git] / ev.c

diff --git a/ev.c b/ev.c
index b6c2126c3469d6baf2c74299b27b2070c8f03c2e..ffd19c66d08269742f0b3594ee9cf89230e8329a 100644 (file)
--- a/ev.c
+++ b/ev.c
@@ -1,3 +1,32 @@
+/*
+ * Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *
+ *     * Redistributions in binary form must reproduce the above
+ *       copyright notice, this list of conditions and the following
+ *       disclaimer in the documentation and/or other materials provided
+ *       with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
 #include <math.h>
 #include <stdlib.h>
 #include <unistd.h>
@@ -12,8 +41,6 @@
 #include <sys/time.h>
 #include <time.h>
 
-#define HAVE_EPOLL 1
-
 #ifndef HAVE_MONOTONIC
 # ifdef CLOCK_MONOTONIC
 #  define HAVE_MONOTONIC 1
@@ -161,6 +188,19 @@ queue_events (W *events, int eventcnt, int type)
     event (events [i], type);
 }
 
+/* called on EBADF to verify fds */
+static void
+fd_recheck ()
+{
+  int fd;
+
+  for (fd = 0; fd < anfdmax; ++fd)
+    if (anfds [fd].wev)
+      if (fcntl (fd, F_GETFD) == -1 && errno == EBADF)
+        while (anfds [fd].head)
+          evio_stop (anfds [fd].head);
+}
+
 /*****************************************************************************/
 
 static struct ev_timer **timers;
@@ -286,6 +326,9 @@ siginit (void)
 static struct ev_idle **idles;
 static int idlemax, idlecnt;
 
+static struct ev_prepare **prepares;
+static int preparemax, preparecnt;
+
 static struct ev_check **checks;
 static int checkmax, checkcnt;
 
@@ -389,11 +432,9 @@ fd_reify (void)
 static void
 call_pending ()
 {
-  int i;
-
-  for (i = 0; i < pendingcnt; ++i)
+  while (pendingcnt)
     {
-      ANPENDING *p = pendings + i;
+      ANPENDING *p = pendings + --pendingcnt;
 
       if (p->w)
         {
@@ -401,8 +442,6 @@ call_pending ()
           p->w->cb (p->w, p->events);
         }
     }
-
-  pendingcnt = 0;
 }
 
 static void
@@ -519,20 +558,22 @@ void ev_loop (int flags)
   double block;
   ev_loop_done = flags & EVLOOP_ONESHOT ? 1 : 0;
 
-  if (checkcnt)
-    {
-      queue_events ((W *)checks, checkcnt, EV_CHECK);
-      call_pending ();
-    }
-
   do
     {
+      /* queue check watchers (and execute them) */
+      if (preparecnt)
+        {
+          queue_events ((W *)prepares, preparecnt, EV_PREPARE);
+          call_pending ();
+        }
+
       /* update fd-related kernel structures */
       fd_reify ();
 
       /* calculate blocking time */
 
-      /* we only need this for !monotonic clock, but as we always have timers, we just calculate it every time */
+      /* we only need this for !monotonic clockor timers, but as we basically
+         always have timers, we just calculate it always */
       ev_now = ev_time ();
 
       if (flags & EVLOOP_NONBLOCK || idlecnt)
@@ -562,15 +603,16 @@ void ev_loop (int flags)
       time_update ();
 
       /* queue pending timers and reschedule them */
-      periodics_reify (); /* absolute timers first */
-      timers_reify (); /* relative timers second */
+      timers_reify (); /* relative timers called last */
+      periodics_reify (); /* absolute timers called first */
 
       /* queue idle watchers unless io or timers are pending */
       if (!pendingcnt)
         queue_events ((W *)idles, idlecnt, EV_IDLE);
 
-      /* queue check and possibly idle watchers */
-      queue_events ((W *)checks, checkcnt, EV_CHECK);
+      /* queue check watchers, to be executed first */
+      if (checkcnt)
+        queue_events ((W *)checks, checkcnt, EV_CHECK);
 
       call_pending ();
     }
@@ -799,6 +841,26 @@ void evidle_stop (struct ev_idle *w)
   ev_stop ((W)w);
 }
 
+void evprepare_start (struct ev_prepare *w)
+{
+  if (ev_is_active (w))
+    return;
+
+  ev_start ((W)w, ++preparecnt);
+  array_needsize (prepares, preparemax, preparecnt, );
+  prepares [preparecnt - 1] = w;
+}
+
+void evprepare_stop (struct ev_prepare *w)
+{
+  ev_clear ((W)w);
+  if (ev_is_active (w))
+    return;
+
+  prepares [w->active - 1] = prepares [--preparecnt];
+  ev_stop ((W)w);
+}
+
 void evcheck_start (struct ev_check *w)
 {
   if (ev_is_active (w))