From: ian <ian>
Date: Sat, 5 Apr 2008 11:37:57 +0000 (+0000)
Subject: before new ownership and interface
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ijackson/git?a=commitdiff_plain;h=9284ae935d726c17345092972d04575873c05e31;p=trains.git

before new ownership and interface
---

diff --git a/hostside/movpos.c b/hostside/movpos.c
index 04cb96e..7722f17 100644
--- a/hostside/movpos.c
+++ b/hostside/movpos.c
@@ -4,7 +4,7 @@
 
 #include "realtime.h"
 
-/*---------- declarations ----------*/
+/*========== declarations ==========*/
 
 typedef struct SomeChange SomeChange;
 
@@ -33,19 +33,22 @@ typedef struct MovPosChangeDetails {
   void *u;
 } ChangeHeader;
 
-/*---------- points ----------*/
+/*========== points ==========*/
 
 /*
- * Currently there is only one queue for the one CDU.
+ * We maintain two queues, one for reserved one for actually confirmed
+ *  requests where we know what we're doing.
  *
- * We maintain a queue of change requests.  The queue can also contain
- * reservations.  We divide time into discrete slots, numbered with
- * clock arithmetic.
+ * We divide time into discrete slots, numbered with clock arithmetic.
  *
  *     cslot         cslot+1      cslot+2
  *
  *     currently     next in      after
  *     changing      line         that
+ *
+ * We increment cslot when we issue a POINT command to the PIC.
+ * In a request, the deadline represents the latest allowable value
+ * of cslot just before that increment.
  */
 
 typedef unsigned PtSlot;
@@ -69,21 +72,13 @@ typedef struct {             /* Allocated Reserved  Confirmed               */
    *  etc.  They are only allowed while we are in a pt_... method function.
    */
 
-/* We increment cslot when we issue a POINT command to the PIC.
- * deadline represents the latest allowable value of cslot
- * just before that increment. */
-
 #define CDU_RECHARGE   250 /*ms*/
 #define POINT_MOVEMENT  50 /*ms*/
 
 #define PT_MAX_QUEUE  15
 
 static PtSlot pt_cslot;
-
-/*
- * We maintain two queues, one for reserved one for actually confirmed
- *  requests where we know what we're doing.
- */
+static int pt_cdu_charged;
 
 todo
  actually fire points: use item, and remove it, etc.
@@ -140,6 +135,51 @@ static void pt__mark_as_allocated(PointReq *r) { /* AX->X */
   r->motions[0].i=0;
 }
 
+static ErrorCode pt__check(void) {
+  /* Checks whether we can meet the currently queued commitments */
+  int future, conf, resv;
+
+  conf=resv=0;
+
+  /* If CDU is charged we can do one thing right away */
+  while (conf < pt_confirmed.n &&
+	 pt_confirmed.l[0].deadline==pt_cslot) {
+    if (!pt_cdu_charged) return EC_Points;
+    if (conf) return EC_Points;
+    conf++;
+  }
+
+  future=1;
+  for (;;) {
+    PointReq *confr= conf < pt_confirmed.n ? pt_confirmed.l[conf] : 0;
+    PointReq *resvr= resv < pt_reserved .n ? pt_reserved .l[conf] : 0;
+    if (!confr && !resvr) break;
+    int confwhen= confr ? confr->deadline - pt_cslot : INT_MAX;
+    int resvwhen= resvr ? resvr->deadline            : INT_MAX;
+    if (resvwhen < confwhen) {
+      usewhen= resvwhen;
+      resv++;
+    } else {
+      usewhen= confwhen;
+      conf++;
+    }
+    if (usewhen > future) return EC_Points;
+    future++;
+  }
+  return 0;
+}
+  
+       ;
+       
+    
+
+
+  for (conf=0;
+       conf < 
+
+    
+}
+
 static ErrorCode pt__enqueue(PointQueue *q, PointReq *r) { /* XA -> X */
   ErrorCode ec;              /* ... where X is R or C and corresponds to q */
                              /* or on error,   XA -> A */
@@ -155,7 +195,7 @@ static ErrorCode pt__enqueue(PointQueue *q, PointReq *r) { /* XA -> X */
   q->l[insat]= r;
   q->n++;
 
-  return pt_check();
+  return pt__check();
   /* if this fails, indep machinery calls pt_destroy which dequeues */
 }
 
@@ -172,6 +212,7 @@ static SomeChange pt_allocate(int alloc_motions) {
 static ErrorCode pt_reserve(SomeChange *chg, Segment *move, int maxdelay_ms) {
   PointReq *r= (PointReq*)chg;
   r->deadline= pt_reldeadline(maxdelay_ms);
+  if (!r->deadline) { pt__mark_as_allocated(r); return EC_Points; }
   return pt_queue_add(&pt_reserved, r);
 }
 
@@ -200,8 +241,21 @@ static ErrorCode pt_request(SomeChange *chg, Segment *move,
   return ec;
 }
 
+/*---------- entrypoints from rest of program ----------*/
+
+static void points_turning_on(void) {
+  pt_cdu_charged= 0;
+}
+
+void on_pic_charged(const PicInsnInfo *pii, const PicInsn *pi, int objnum) {
+  pt_cdu_charged= 1;
+  if (sta_state <= Sta_Settling) return;
+  fixme check fault arrangements wrt cdu and points etc.
+  fixme do something here
+}
+
 
-/*---------- method-independent machinery ----------*/
+/*========== method-independent machinery ==========*/
 
 static const MethodInfo methodinfos[]= {
   { nomove_allocate, nomove_reserve, nomove_request, nomove_cancel }