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

3 files changed, 352 insertions, 4 deletions

diff --git a/src/gsmd/Makefile.am b/src/gsmd/Makefile.am
index f874fca..49d96e3 100644
--- a/src/gsmd/Makefile.am
+++ b/src/gsmd/Makefile.am
@@ -6,7 +6,7 @@ sbin_PROGRAMS = gsmd
 
 gsmd_CFLAGS = -D PLUGINDIR=\"$(plugindir)\"
 gsmd_SOURCES = gsmd.c atcmd.c select.c machine.c vendor.c unsolicited.c log.c \
-	       usock.c talloc.c operator_cache.c ext_response.c
+	       usock.c talloc.c timer.c operator_cache.c ext_response.c
 gsmd_LDADD = -ldl
 gsmd_LDFLAGS = -Wl,--export-dynamic
 
diff --git a/src/gsmd/gsmd.c b/src/gsmd/gsmd.c
index 3105bee..65ce6f8 100644
--- a/src/gsmd/gsmd.c
+++ b/src/gsmd/gsmd.c
@@ -44,9 +44,111 @@
 #include <gsmd/vendorplugin.h>
 #include <gsmd/talloc.h>
 
+#define GSMD_ALIVECMD		"ATE0"
+#define GSMD_ALIVE_INTERVAL	5*60
+#define GSMD_ALIVE_TIMEOUT	30
+
+/* alive checking */
+
+struct gsmd_alive_priv {
+	struct gsmd *gsmd;
+	int alive_responded;
+};
+
+static int gsmd_alive_cb(struct gsmd_atcmd *cmd, void *ctx, char *resp)
+{
+	struct gsmd_alive_priv *alp = ctx;
+
+	DEBUGP("alp=%p - `%s' returned `%s'\n", alp, cmd->buf, resp);
+	if (!strcmp(resp, "OK")) {
+		DEBUGP("`%s' returned `%s': OK\n", cmd->buf, resp);
+		alp->alive_responded = 1;
+	}
+	return 0;
+}
+
+static void alive_tmr_cb(struct gsmd_timer *tmr, void *data)
+{
+	struct gsmd_alive_priv *alp = data;
+
+	DEBUGP("alp=%p gsmd_alive timer expired\n", alp);
+
+	if (alp->alive_responded == 0) {
+		DEBUGP("modem dead!\n");
+		exit(3);
+	} else
+		DEBUGP("modem alive!\n");
+
+	/* FIXME: update some global state */
+
+	gsmd_timer_free(tmr);
+	talloc_free(alp);
+}
+
+static int gsmd_modem_alive(struct gsmd *gsmd)
+{
+	struct gsmd_atcmd *cmd;
+	struct gsmd_alive_priv *alp;
+	struct timeval tv;
+
+	alp = talloc(gsmd_tallocs, struct gsmd_alive_priv);
+	if (!alp)
+		return -ENOMEM;
+
+	alp->gsmd = gsmd;
+	alp->alive_responded = 0;
+
+	tv.tv_sec = GSMD_ALIVE_TIMEOUT;
+	cmd = atcmd_fill(GSMD_ALIVECMD, strlen(GSMD_ALIVECMD)+1, 
+			 &gsmd_alive_cb, alp, 0);
+	if (!cmd) {
+		talloc_free(alp);
+		return -ENOMEM;
+	}
+
+	tv.tv_usec = 0;
+	gsmd_timer_create(&tv, &alive_tmr_cb, alp);
+	
+	return atcmd_submit(gsmd, cmd);
+}
+
+static void alive_interval_tmr_cb(struct gsmd_timer *tmr, void *data)
+{
+	struct gsmd *gsmd = data;
+
+	DEBUGP("interval expired, starting next alive inquiry\n");
+
+	/* start a new alive check iteration */
+	gsmd_modem_alive(gsmd);
+
+	/* re-add the timer for the next interval */
+	tmr->expires.tv_sec = GSMD_ALIVE_INTERVAL;
+	tmr->expires.tv_usec = 0;
+
+	gsmd_timer_register(tmr);
+}
+
+static int gmsd_alive_start(struct gsmd *gsmd)
+{
+	struct timeval tv;
+
+	tv.tv_sec = GSMD_ALIVE_INTERVAL;
+	tv.tv_usec = 0;
+
+	if (!gsmd_timer_create(&tv, &alive_interval_tmr_cb, gsmd))
+		return -1;
+
+	gsmd_modem_alive(gsmd);
+
+	return 0;
+}
+
+
+/* initial startup code */
+
 static int gsmd_test_atcb(struct gsmd_atcmd *cmd, void *ctx, char *resp)
 {
-	printf("`%s' returned `%s'\n", cmd->buf, resp);
+	DEBUGP("`%s' returned `%s'\n", cmd->buf, resp);
 	return 0;
 }
 
@@ -60,7 +162,7 @@ int gsmd_simplecmd(struct gsmd *gsmd, char *cmdtxt)
 	return atcmd_submit(gsmd, cmd);
 }
 
-int gsmd_initsettings(struct gsmd *gsmd)
+static int gsmd_initsettings2(struct gsmd *gsmd)
 {
 	int rc;
 	
@@ -92,6 +194,28 @@ int gsmd_initsettings(struct gsmd *gsmd)
 		return rc;
 }
 
+/* we submit the first atcmd and wait synchronously for a valid response */
+static int firstcmd_atcb(struct gsmd_atcmd *cmd, void *ctx, char *resp)
+{
+	struct gsmd *gsmd = ctx;
+	DEBUGP("`%s' returned `%s'\n", cmd->buf, resp);
+	if (strcmp(resp, "OK")) {
+		fprintf(stderr, "response '%s' to initial command invalid", resp);
+		exit(1);
+	}
+	return gsmd_initsettings2(gsmd);
+}
+
+int gsmd_initsettings(struct gsmd *gsmd)
+{
+	struct gsmd_atcmd *cmd;
+	cmd = atcmd_fill("ATE0V1", strlen("ATE0V1")+1, &firstcmd_atcb, gsmd, 0);
+	if (!cmd)
+		return -ENOMEM;
+	
+	return atcmd_submit(gsmd, cmd);
+}
+
 struct bdrt {
 	int bps;
 	u_int32_t b;
@@ -195,6 +319,8 @@ static void sig_handler(int signr)
 		break;
 	case SIGUSR1:
 		talloc_report_full(gsmd_tallocs, stderr);
+	case SIGALRM:
+		gsmd_timer_check_n_run();
 		break;
 	}
 }
@@ -215,6 +341,7 @@ int main(int argc, char **argv)
 	signal(SIGINT, sig_handler);
 	signal(SIGSEGV, sig_handler);
 	signal(SIGUSR1, sig_handler);
+	signal(SIGALRM, sig_handler);
 	
 	gsmd_tallocs = talloc_named_const(NULL, 1, "GSMD");
 
@@ -285,6 +412,8 @@ int main(int argc, char **argv)
 		exit(1);
 	}
 
+	gsmd_timer_init();
+
 	if (gsmd_machine_plugin_init(&g, machine_name, vendor_name) < 0) {
 		fprintf(stderr, "no machine plugins found\n");
 		exit(1);
@@ -326,6 +455,8 @@ int main(int argc, char **argv)
 
 	if (g.interpreter_ready)
 		gsmd_initsettings(&g);
+	
+	gmsd_alive_start(&g);
 
 	gsmd_opname_init(&g);
 
@@ -335,7 +466,7 @@ int main(int argc, char **argv)
 			continue;
 
 		if (ret < 0) {
-			if (errno == -EINTR)
+			if (errno == EINTR)
 				continue;
 			else {
 				DEBUGP("select returned error (%s)\n",
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();
+}