Magproto: Improve performance on reads by turning off hanshaking. Stability

 fix on successive transfers.

diff --git a/magproto.c b/magproto.c
index c74ca60b33b8ddae8c457ef4c426778ff490a43a..25bf50a7f61b5c5a86147f0d81e0f8e143bf3d75 100644 (file)
--- a/magproto.c
+++ b/magproto.c
@@ -50,6 +50,15 @@ static int route_out_count;
 static int waypoint_read_count;
 static int wpt_len = 8;
 static const char *curfname;
+/*
+ * Magellan's firmware is *horribly* slow to send the next packet after
+ * we turn around an ack while we are reading from the device.  It's
+ * quite spiffy when we're writing to the device.   Since we're *way*
+ * less likely to lose data while reading from it than it is to lose data
+ * when we write to it, we turn off the acks when we are predominatly
+ *  reading.
+ */
+static int suppress_ack;
 
 typedef enum {
        mrs_handoff = 0,
@@ -471,8 +480,8 @@ retry:
                         */
                        const char *s = strrchr(curfname, GB_PATHSEP);
                        char *e;
-
                        trk_head = route_head_alloc();
+
                        if (s) {
                                s++; /* Skip path delim */
                        }  else {
@@ -509,8 +518,10 @@ retry:
                found_done = 1;
                return;
        } 
-       if (magrxstate != mrs_handoff)
+
+       if (magrxstate != mrs_handoff) {
                mag_writeack(isum);
+       }
 }
 
 static void *serial_handle = NULL;
@@ -637,7 +648,7 @@ mag_rd_init_common(const char *portname)
 {
        time_t now, later;
        waypoint_read_count = 0;
-       
+
        if (bs) {
                bitrate=atoi(bs);
        }
@@ -646,8 +657,9 @@ mag_rd_init_common(const char *portname)
        if (!mkshort_handle) {
                mkshort_handle = mkshort_new_handle();
        }
-
-       if (!noack)
+       
+       mag_handoff();
+       if (!noack && !suppress_ack) 
                mag_handon();
 
        now = current_time();
@@ -708,6 +720,7 @@ static void
 mag_rd_init(const char *portname)
 {
        explorist = 0;
+       suppress_ack = 1;
        mag_rd_init_common(portname);
 }
 
@@ -721,6 +734,7 @@ magX_rd_init(const char *portname)
 static void
 mag_wr_init_common(const char *portname)
 {
+       suppress_ack = 0;
        if (bs) {
                bitrate=atoi(bs);
        }
@@ -1093,6 +1107,7 @@ mag_read(void)
           }
         }
 
+       found_done = 0;
         if (global_opts.masked_objective & WPTDATAMASK) {
                  magrxstate = mrs_handoff;
           if (!is_file) 
@@ -1103,6 +1118,7 @@ mag_read(void)
           }
         }
 
+       found_done = 0;
         if (global_opts.masked_objective & RTEDATAMASK) {
                  magrxstate = mrs_handoff;
           if (!is_file) {