Add 'modem alive' detection. We inquire every five minutes if the modem is still alive.

git-svn-id: http://svn.openmoko.org/trunk/src/target/gsm@2130 99fdad57-331a-0410-800a-d7fa5415bdb3

1 files changed, 217 insertions, 0 deletions

diff --git a/src/gsmd/timer.c b/src/gsmd/timer.c
new file mode 100644
index 0000000..5200690
--- /dev/null
+++ b/src/gsmd/timer.c
@@ -0,0 +1,217 @@
+/* gsmd timer code
+ *
+ * (C) 2000-2005 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2007 by OpenMoko, Inc.
+ * Written by Harald Welte <laforge@openmoko.org>
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/time.h>
+#include <time.h>
+
+#include <common/linux_list.h>
+
+#include "gsmd.h"
+
+#include <gsmd/gsmd.h>
+#include <gsmd/talloc.h>
+
+static LLIST_HEAD(gsmd_timers);
+static void *__tmr_ctx;
+
+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)
+{
+	res->tv_sec = from->tv_sec - sub->tv_sec;
+	res->tv_usec = from->tv_usec - sub->tv_usec;
+
+	while (res->tv_usec < 0) {
+		res->tv_sec -= 1;
+		res->tv_usec += 1000000;
+	}
+
+	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 gsmd_timer *cur;
+	struct timeval min, now, diff;
+	struct itimerval iti;
+	int ret;
+
+	gettimeofday(&now, NULL);
+
+retry:
+	if (llist_empty(&gsmd_timers))
+		return 0;
+
+	llist_for_each_entry(cur, &gsmd_timers, list) {
+		if (gsmd_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 gsmd_timer_check_n_run(void)
+{
+	struct gsmd_timer *cur, *cur2;
+	struct timeval now;
+
+	if (gettimeofday(&now, NULL) < 0)
+		return;
+
+	llist_for_each_entry_safe(cur, cur2, &gsmd_timers, list) {
+		if (tv_later(&now, &cur->expires)) {
+			/* fist delete it from the list of timers */
+			llist_del(&cur->list);
+			/* then call.  called function can re-add it */
+			(cur->cb)(cur, cur->data);
+		}
+	}
+
+	calc_next_expiration();
+}
+
+int gsmd_timer_init(void)
+{
+	__tmr_ctx = talloc_named_const(gsmd_tallocs, 1, "timers");
+
+	return 0;
+}
+
+struct gsmd_timer *gsmd_timer_alloc(void)
+{
+	struct gsmd_timer *tmr;
+
+	tmr = talloc_size(__tmr_ctx, sizeof(*tmr));
+	return tmr;
+}
+
+int gsmd_timer_register(struct gsmd_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, &gsmd_timers);
+
+	/* re-calculate next expiration */
+	calc_next_expiration();
+
+	return 0;
+}
+
+struct gsmd_timer *gsmd_timer_create(struct timeval *expires,
+				     void (*cb)(struct gsmd_timer *tmr,
+						void *data),
+				     void *data)
+{
+	struct gsmd_timer *tmr = gsmd_timer_alloc();
+	int rc;
+
+	if (!tmr)
+		return NULL;
+
+	memcpy(&tmr->expires, expires, sizeof(tmr->expires));
+	tmr->cb = cb;
+	tmr->data = data;
+
+	rc = gsmd_timer_register(tmr);
+	if (rc < 0) {
+		talloc_free(tmr);
+		return NULL;
+	}
+
+	return tmr;
+}
+
+void gsmd_timer_unregister(struct gsmd_timer *timer)
+{
+	llist_del(&timer->list);
+
+	/* re-calculate next expiration */
+	calc_next_expiration();
+}