introduce core timer handling

diff --git a/include/ulogd/ulogd.h b/include/ulogd/ulogd.h
index a8628dbbe3e2eb00fed3200ab3187559577efad5..7fad2b4b6c49c3ac3fcb328dd0446569d1502e95 100644 (file)
--- a/include/ulogd/ulogd.h
+++ b/include/ulogd/ulogd.h
@@ -238,4 +238,18 @@ struct ulogd_fd {
 int ulogd_register_fd(struct ulogd_fd *ufd);
 void ulogd_unregister_fd(struct ulogd_fd *ufd);
 
+/***********************************************************************
+ * timer handling
+ ***********************************************************************/
+
+struct ulogd_timer {
+       struct llist_head list;
+       struct timeval expires;
+       void (*cb)(void *data);
+       void *data;
+};
+
+int ulogd_register_timer(struct ulogd_timer *timer);
+void ulogd_unregister_timer(struct ulogd_timer *timer);
+
 #endif /* _ULOGD_H */

diff --git a/src/Makefile.am b/src/Makefile.am
index 2764b4b5abfd2be95952572497f2d7a8a8efa6d4..d2559b71afceb0ca6a3a47dd20a4d76cc0ddbea8 100644 (file)
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -3,5 +3,5 @@ INCLUDES = $(all_includes) -I$(top_srcdir)/include
 
 bin_PROGRAMS = ulogd
 
-ulogd_SOURCES = ulogd.c select.c conffile.c
+ulogd_SOURCES = ulogd.c select.c timer.c conffile.c
 ulogd_LDFLAGS = -export-dynamic

diff --git a/src/timer.c b/src/timer.c
new file mode 100644 (file)
index 0000000..47bb7c5
--- /dev/null
+++ b/src/timer.c
@@ -0,0 +1,167 @@
+/* ulogd, Version $LastChangedRevision: 476 $
+ *
+ * $Id: ulogd.c 476 2004-07-23 03:19:35Z laforge $
+ *
+ * userspace logging daemon for the netfilter subsystem
+ *
+ * (C) 2000-2005 by Harald Welte <laforge@gnumonks.org>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 
+ *  as published by the Free Software Foundation
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/time.h>
+#include <time.h>
+
+#include <ulogd/ulogd.h>
+#include <ulogd/linuxlist.h>
+
+static LLIST_HEAD(ulogd_timers);
+
+static void tv_normalize(struct timeval *out)
+{
+       out->tv_sec += (out->tv_usec / 1000000);
+       out->tv_usec = (out->tv_usec % 1000000);
+}
+
+/* subtract two struct timevals */
+static int tv_sub(struct timeval *res, const struct timeval *from,
+                 const struct timeval *sub)
+{
+       /* FIXME: this stinks.  Deal with wraps, carry, ... */
+       res->tv_sec = from->tv_sec - sub->tv_sec;
+       res->tv_usec = from->tv_usec - sub->tv_usec;
+
+       return 0;
+}
+
+static int tv_add(struct timeval *res, const struct timeval *a1,
+                 const struct timeval *a2)
+{
+       unsigned int carry;
+
+       res->tv_sec = a1->tv_sec + a2->tv_sec;
+       res->tv_usec = a1->tv_usec + a2->tv_usec;
+
+       tv_normalize(res);
+}
+
+static int tv_later(const struct timeval *expires, const struct timeval *now)
+{
+       if (expires->tv_sec < now->tv_sec)
+               return 0;
+       else if (expires->tv_sec > now->tv_sec)
+               return 1;
+       else /* if (expires->tv_sec == now->tv_sec */ {
+               if (expires->tv_usec >= now->tv_usec)
+                       return 1;
+       }
+
+       return 0;
+}
+
+static int tv_smaller(const struct timeval *t1, const struct timeval *t2)
+{
+       return tv_later(t2, t1);
+}
+
+static int calc_next_expiration(void)
+{
+       struct ulogd_timer *cur;
+       struct timeval min, now, diff;
+       struct itimerval iti;
+       int ret;
+
+retry:
+       if (llist_empty(&ulogd_timers))
+               return 0;
+
+       llist_for_each_entry(cur, &ulogd_timers, list) {
+               if (ulogd_timers.next == &cur->list)
+                       min = cur->expires;
+
+               if (tv_smaller(&cur->expires, &min))
+                       min = cur->expires;
+       }
+
+       if (tv_sub(&diff, &min, &now) < 0) {
+               /* FIXME: run expired timer callbacks */
+               /* we cannot run timers from here since we might be
+                * called from register_timer() within check_n_run() */
+
+               /* FIXME: restart with next minimum timer */
+               goto retry;
+       }
+
+       /* re-set kernel timer */
+       memset(&iti, 0, sizeof(iti));
+       memcpy(&iti.it_value, &diff, sizeof(iti.it_value));
+       ret = setitimer(ITIMER_REAL, &iti, NULL);
+       if (ret < 0)
+               return ret;
+
+       return 0;
+}
+
+void ulogd_timer_check_n_run(void)
+{
+       struct ulogd_timer *cur, *cur2;
+       struct timeval now;
+
+       if (gettimeofday(&now, NULL) < 0)
+               return;
+
+       llist_for_each_entry_safe(cur, cur2, &ulogd_timers, list) {
+               if (tv_later(&cur->expires, &now)) {
+                       /* fist delete it from the list of timers */
+                       llist_del(cur);
+                       /* then call.  called function can re-add it */
+                       (cur->cb)(cur->data);
+               }
+       }
+
+       calc_next_expiration();
+}
+
+
+int ulogd_register_timer(struct ulogd_timer *timer)
+{
+       int ret;
+       struct timeval tv;
+
+       ret = gettimeofday(&tv, NULL);
+       if (ret < 0)
+               return ret;
+
+       /* convert expiration time into absoulte time */
+       timer->expires.tv_sec += tv.tv_sec;
+       timer->expires.tv_usec += tv.tv_usec;
+
+       llist_add_tail(&timer->list, &ulogd_timers);
+
+       /* re-calculate next expiration */
+       calc_next_expiration();
+
+       return 0;
+}
+
+void ulogd_unregister_timer(struct ulogd_timer *timer)
+{
+       llist_del(&timer->list);
+
+       /* re-calculate next expiration */
+       calc_next_expiration();
+}

diff --git a/src/ulogd.c b/src/ulogd.c
index 1acfa3363b3b6ba05ad317a0c91f1ed1383caa5d..c7d80e6b76ea30085cbc4a9eeaad1bcd55b34e60 100644 (file)
--- a/src/ulogd.c
+++ b/src/ulogd.c
@@ -824,6 +824,9 @@ static void signal_handler(int signal)
                                sigterm_handler(signal);
                }
                break;
+       case SIGALRM:
+               ulogd_timer_check_n_run();
+               break;
        default:
                break;
        }
@@ -966,7 +969,9 @@ int main(int argc, char* argv[])
 
        signal(SIGTERM, &sigterm_handler);
        signal(SIGHUP, &signal_handler);
+       signal(SIGALRM, &signal_handler);
        signal(SIGUSR1, &signal_handler);
+       signal(SIGUSR2, &signal_handler);
 
        ulogd_log(ULOGD_INFO, 
                  "initialization finished, entering main loop\n");