From: ian <ian>
Date: Tue, 20 May 2008 21:38:16 +0000 (+0000)
Subject: separate pred_getmovpos and report_getmovpos, and make the former less buggy
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ijackson/git?a=commitdiff_plain;h=0640d2b9005ff56506942d9a5aa3b4164d892460;p=trains.git

separate pred_getmovpos and report_getmovpos, and make the former less buggy
---

diff --git a/hostside/safety.c b/hostside/safety.c
index 8e901a0..9f315ab 100644
--- a/hostside/safety.c
+++ b/hostside/safety.c
@@ -266,13 +266,12 @@ typedef struct {
     neednewplan:1,
     stopping:1,
     done_first_new_fdet:1,
-    usecurrentposn:1, /* for pred_getmovpos */
+    usecurrentposn:1, /* for {pred,report}_getmovpos */
     optimistic:1, /* for autopoint */ 
     walk_compute_polarise:1, /* nose_nextseg still needs to worry */
     need_polarise:1, /* when we commit */
     train_polarity_inverted:1, /* right now, or if know_best, the best */
-    know_best_polarity:1, /* longest-lasting into the future */
-    alwaysusemotions:1; /* for report_train_ownerships, uses ->motion */
+    know_best_polarity:1; /* longest-lasting into the future */
   TrackLocation nose, fdet, tail;
   TrackAdvanceContext nosec, tailc, fdetc;
   TimeInterval elapsed; /* from now, minimum */
@@ -395,14 +394,10 @@ static void pred_callback_debug(const char *what, TrackLocation *t,
 static int pred_getmovpos(TrackLocation *t, TrackAdvanceContext *c,
 			  MovPosComb *use_io) {
   PredictUserContext *u= c->u;
-  if (u->usecurrentposn) return 0;
-  if (u->alwaysusemotions) {
-    if (t->seg->motion)
-      *use_io= movpos_change_intent(t->seg->motion);
-  } else if (t->seg->moving || t->seg->pred_vacated) {
-    if (t->seg->motion_newplan)
-      *use_io= movpos_change_intent(t->seg->motion_newplan);
-  }
+  if (!u->usecurrentposn &&
+      !t->seg->now_present &&
+      t->seg->motion_newplan)
+    *use_io= movpos_change_intent(t->seg->motion_newplan);
   if (*use_io<0) safety_panic(u->train, t->seg,
 	   		      "track route unexpectedly not known");
   return 0;
@@ -487,6 +482,8 @@ static int nose_nextseg(TrackLocation *t, TrackAdvanceContext *c,
     }
   }
 
+  int autopoint= u->train->autopoint && t->seg->autopoint;
+
   if (t->seg->motion_newplan) {
     route_plan= movpos_change_intent(t->seg->motion);
     *mpc_io= route_plan;
@@ -498,6 +495,7 @@ static int nose_nextseg(TrackLocation *t, TrackAdvanceContext *c,
     if (route_plan != u->desire_movposcomb)
       return predict_problem(u, t->seg, " proposed route would be against"
 			     " approaching train");
+    autopoint= 1;
   } else if (t->seg->motion) {
     /* We already have a plan. */
     route_plan= movpos_change_intent(t->seg->motion);
@@ -530,7 +528,7 @@ static int nose_nextseg(TrackLocation *t, TrackAdvanceContext *c,
     max_ms= u->elapsed;
   }
 
-  if (!u->train->autopoint || !t->seg->autopoint)
+  if (!autopoint)
     return predict_problem(u,t->seg,"will not automatically set route");
 
   ec= movpos_reserve(t->seg, max_ms, &t->seg->motion_newplan,
@@ -706,8 +704,8 @@ ErrorCode predict(Train *tra, struct timeval tnow, unsigned flags,
   u.desire_movposcomb= desire_movposcomb;
 
   oprintf(DUPO("safety") " predict ***starting*** %s%s maxspeed=%f"
-	  " (speed %f try %f, step %d%s) stopdist=%d flags=%c%c"
-	  " desire=%s/%s %s\n",
+	  " (speed %f try %f, step %d%s) stopdist=%d flags=%c%c%s"
+	  " desire=%s/%s\n",
 	  tra->backwards?"-":"",tra->pname,
 	  u.maxspeed, tra->speed.speed, tra->speed.try_speed, tra->speed.step,
 	  tra->speed.decel.running ? " decel" : "",
@@ -970,13 +968,22 @@ void report_train_position(Train *tra) {
 	  tra->foredetect->i->pname, tra->maxinto, tra->uncertainty);
 }  
   
+static int report_getmovpos(TrackLocation *t, TrackAdvanceContext *c,
+			    MovPosComb *use_io) {
+  PredictUserContext *u= c->u;
+  if (!u->usecurrentposn && t->seg->motion)
+    *use_io= movpos_change_intent(t->seg->motion);
+  assert(*use_io>=0);
+  return 0;
+}
+
 static int report_nextseg(TrackLocation *t, struct TrackAdvanceContext *c,
 			  MovPosComb *mpc, const TrackLocation *before) {
   PredictUserContext *u= c->u;
   char flags[6];
   int r;
 
-  if (u->alwaysusemotions) /* we've had foredetect */
+  if (!u->usecurrentposn) /* we've had foredetect */
     if (++u->lookahead > u->train->plan_lookahead_nsegs)
       return -1;
 
@@ -989,13 +996,12 @@ static int report_nextseg(TrackLocation *t, struct TrackAdvanceContext *c,
   if (t->seg == u->train->foredetect) {
     strcat(flags,"!");
     u->usecurrentposn= 0;
-    u->alwaysusemotions= 1;
   }
 
   oprintf(UPO," %s%s", t->backwards?"-":"", t->seg->i->pname);
 
   if (t->seg->i->n_poscombs > 1) {
-    r= pred_getmovpos(t,c,mpc);  assert(!r);  assert(*mpc>=0);
+    r= report_getmovpos(t,c,mpc);  assert(!r);  assert(*mpc>=0);
     oprintf(UPO,"/%s", t->seg->i->poscombs[*mpc].pname);
   }
   oprintf(UPO,"%s",flags);
@@ -1010,7 +1016,6 @@ void report_train_ownerships(Train *tra, Segment *hindmost,
   memset(&u,0,sizeof(u));
   u.train= tra;
   u.hindmost= 0;
-  u.alwaysusemotions= always_use_motions;
   u.usecurrentposn= !always_use_motions;
   
   /* Walk along the train printing its segments: */
@@ -1022,7 +1027,7 @@ void report_train_ownerships(Train *tra, Segment *hindmost,
 
   u.nosec.distance= TL_DIST_INF;;
   u.nosec.nextseg= report_nextseg;
-  u.nosec.getmovpos= pred_getmovpos;
+  u.nosec.getmovpos= report_getmovpos;
   u.nosec.u= &u;
   u.hindmost= hindmost;