Add timeout on wait-for-ACK to SiRF driver.

Correct initialization observed oon SiRF-III.  All regression tests pass.

4 files changed, 28 insertions, 8 deletions

diff --git a/TODO b/TODO
index 13592e2e..d27e98c1 100644
--- a/TODO
+++ b/TODO
@@ -20,7 +20,7 @@ month is quite low.
 
 **** In gpsmon's PPS Offset field
 
-Presently PPS Offset is displayed in direct mode for NMEA, SiRF, and
+resently PPS Offset is displayed in direct mode for NMEA, SiRF, and
 UBX devices.  Others should probably do likewise, notably the
 Motorola Oncore and Garmin drivers.
 
diff --git a/driver_sirf.c b/driver_sirf.c
index 942915d2..d9bcbbd5 100644
--- a/driver_sirf.c
+++ b/driver_sirf.c
@@ -46,6 +46,12 @@
 #define HI(n)		((n) >> 8)
 #define LO(n)		((n) & 0xff)
 
+/*
+ * According to the protocol reference, if you don't get ACK/NACK in response
+ * to a control send withing 6 seconds, you should just retry.
+ */
+#define SIRF_RETRY_TIME	6
+
 /*@ +charint @*/
 /* Poll Software Version MID 132 */
 static unsigned char versionprobe[] = {
@@ -237,7 +243,10 @@ static bool sirf_write(struct gps_device_t *session, unsigned char *msg)
      * lower-powered processor that apparently has trouble keeping up.  
      * Now you have to wait for the ACK, otherwise chaos ensues.
      */
-    if (session->driver.sirf.ack_await > 0) {
+    if (time(NULL) - session->driver.sirf.last_send > SIRF_RETRY_TIME)
+	session->driver.sirf.need_ack = false;
+    /* can also be false because ACK was received after last send */
+    if (session->driver.sirf.need_ack) {
 	gpsd_report(session->context->debug, LOG_WARN,
 		    "SiRF: write of control type %02x failed, awaiting ACK.\n",
 		    msg[4]);
@@ -260,7 +269,8 @@ static bool sirf_write(struct gps_device_t *session, unsigned char *msg)
 		"SiRF: Writing control type %02x:\n", msg[4]);
     ok = (gpsd_write(session, (const char *)msg, len+8) == (ssize_t) (len+8));
  
-    session->driver.sirf.ack_await++;
+    session->driver.sirf.need_ack = true;
+    session->driver.sirf.last_send = time(NULL);
     return (ok);
 }
 
@@ -1230,14 +1240,14 @@ gps_mask_t sirf_parse(struct gps_device_t * session, unsigned char *buf,
     case 0x0b:			/* Command Acknowledgement MID 11 */
 	gpsd_report(session->context->debug, LOG_PROG,
 		    "SiRF: ACK 0x0b: %02x\n", getub(buf, 1));
-	session->driver.sirf.ack_await--;
+	session->driver.sirf.need_ack = false;
 	return 0;
 
     case 0x0c:			/* Command NAcknowledgement MID 12 */
 	gpsd_report(session->context->debug, LOG_PROG,
 		    "SiRF: NAK 0x0c: %02x\n", getub(buf, 1));
 	/* ugh -- there's no alternative but silent failure here */
-	session->driver.sirf.ack_await--;
+	session->driver.sirf.need_ack = false;
 	return 0;
 
     case 0x0d:			/* Visible List MID 13 */
@@ -1391,7 +1401,10 @@ static void sirfbin_event_hook(struct gps_device_t *session, event_t event)
 
     if (event == event_configure) {
 	/* might not be time for the next init string yet */ 
-	if (session->driver.sirf.ack_await > 0)
+	if (time(NULL) - session->driver.sirf.last_send > SIRF_RETRY_TIME)
+	    session->driver.sirf.need_ack = false;
+	/* can also be false because ACK was received after last send */
+	if (session->driver.sirf.need_ack)
 	    return;
 
 	switch (session->driver.sirf.cfg_stage++) {
diff --git a/gpsd.h-tail b/gpsd.h-tail
index b9b1ea67..a2604d7b 100644
--- a/gpsd.h-tail
+++ b/gpsd.h-tail
@@ -545,7 +545,8 @@ struct gps_device_t {
 #endif /* GEOSTAR_ENABLE */
 #ifdef SIRF_ENABLE
 	struct {
-	    int ack_await;		/* if NZ we're awaiting ACK */
+	    bool need_ack;		/* if NZ we're awaiting ACK */
+	    time_t last_send;		/* for tracking send timeouts */
 	    unsigned int cfg_stage;	/* configuration stage counter */
 	    unsigned int driverstate;	/* for private use */
 #define SIRF_LT_231	0x01		/* SiRF at firmware rev < 231 */
diff --git a/gpsmon.c b/gpsmon.c
index 6eae3e5b..54bd0f59 100644
--- a/gpsmon.c
+++ b/gpsmon.c
@@ -1158,7 +1158,13 @@ int main(int argc, char **argv)
     else 
 	devicename = argv[optind];
 
-    (void)strlcpy(session.gpsdata.dev.path, devicename,
+    /* backward compatibilty: accept a bare server name */
+    if (strchr(devicename, ':') == NULL && devicename[0] != '/')
+	(void) strlcpy(session.gpsdata.dev.path, 
+		       "tcp://", sizeof(session.gpsdata.dev.path));
+    else
+	session.gpsdata.dev.path[0] = '\0';
+    (void)strlcat(session.gpsdata.dev.path, devicename,
 		  sizeof(session.gpsdata.dev.path));
 
     if (gpsd_activate(&session, O_PROBEONLY) == -1) {