From 26dcecebdb2622147c5ff0488c0dde1e41414eaf Mon Sep 17 00:00:00 2001
From: steve <steve>
Date: Fri, 31 Mar 2000 07:08:39 +0000
Subject: [PATCH]  allow cancelling of cbValueChange events.

---
 vpi/sys_display.c  | 15 ++++++++++--
 vvm/vpi_callback.c | 58 ++++++++++++++++++++++++++++++++--------------
 vvm/vpi_priv.h     | 12 ++++++++--
 vvm/vpi_signal.c   | 11 ++++++---
 4 files changed, 72 insertions(+), 24 deletions(-)

diff --git a/vpi/sys_display.c b/vpi/sys_display.c
index 24de467ca..243d25b41 100644
--- a/vpi/sys_display.c
+++ b/vpi/sys_display.c
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: sys_display.c,v 1.11 2000/02/23 02:56:56 steve Exp $"
+#ident "$Id: sys_display.c,v 1.12 2000/03/31 07:08:39 steve Exp $"
 #endif
 
 # include  "vpi_user.h"
@@ -300,11 +300,14 @@ static int monitor_cb_1(p_cb_data cause)
 {
       struct t_cb_data cb;
       struct t_vpi_time time;
+	/* The user_data of the callback is a pointer to the callback
+	   handle. I use this to reschedule the callback if needed. */
+      vpiHandle*cbh = (vpiHandle*) (cause->user_data);
 
 	/* Reschedule this event so that it happens for the next
 	   trigger on this variable. */
       cb = *cause;
-      vpi_register_cb(&cb);
+      *cbh = vpi_register_cb(&cb);
       
       if (monitor_scheduled) return 0;
 
@@ -363,6 +366,11 @@ static int sys_monitor_calltf(char*name)
 	    switch (vpi_get(vpiType, monitor_info.items[idx])) {
 		case vpiNet:
 		case vpiReg:
+		    /* Monitoring reg and net values involves setting
+		       a collback for value changes. pass the storage
+		       pointer for the callback itself as user_data so
+		       that the callback can refresh itself. */
+		  cb.user_data = (char*)(monitor_callbacks+idx);
 		  cb.obj = monitor_info.items[idx];
 		  monitor_callbacks[idx] = vpi_register_cb(&cb);
 		  break;
@@ -413,6 +421,9 @@ void sys_display_register()
 
 /*
  * $Log: sys_display.c,v $
+ * Revision 1.12  2000/03/31 07:08:39  steve
+ *  allow cancelling of cbValueChange events.
+ *
  * Revision 1.11  2000/02/23 02:56:56  steve
  *  Macintosh compilers do not support ident.
  *
diff --git a/vvm/vpi_callback.c b/vvm/vpi_callback.c
index befbd7a55..1b47a5778 100644
--- a/vvm/vpi_callback.c
+++ b/vvm/vpi_callback.c
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: vpi_callback.c,v 1.6 2000/02/23 02:56:56 steve Exp $"
+#ident "$Id: vpi_callback.c,v 1.7 2000/03/31 07:08:39 steve Exp $"
 #endif
 
 # include  "vpi_priv.h"
@@ -69,20 +69,15 @@ static void vpip_call_callback(void*cp)
 void vpip_run_value_changes(struct __vpiSignal*sig)
 {
       struct __vpiCallback*cur;
-      if (sig->monitor == 0) return;
-
-      while (sig->monitor->next != sig->monitor) {
-	    cur = sig->monitor->next;
-	    sig->monitor->next = cur->next;
 
+      while (sig->mfirst) {
+	    cur = sig->mfirst;
+	    sig->mfirst = cur->next;
+	    if (sig->mfirst == 0)
+		  sig->mlast = 0;
 	    cur->next = 0;
 	    cur->ev = vpip_sim_insert_event(0, cur, vpip_call_callback, 0);
       }
-
-      cur = sig->monitor;
-      sig->monitor = 0;
-      cur->next = 0;
-      cur->ev = vpip_sim_insert_event(0, cur, vpip_call_callback, 0);
 }
 
 /*
@@ -110,18 +105,21 @@ static void go_value_change(struct __vpiCallback*rfp)
       assert((sig->base.vpi_type->type_code == vpiReg)
 	     || (sig->base.vpi_type->type_code == vpiNet));
 
+
 	/* If there are no monitor events, start the list. */
-      if (sig->monitor == 0) {
-	    rfp->next = rfp;
-	    sig->monitor = rfp;
+      if (sig->mfirst == 0) {
+	    rfp->sig = sig;
+	    rfp->next = 0;
+	    sig->mfirst = rfp;
+	    sig->mlast = rfp;
 	    return;
       }
 
 	/* Put me at the end of the list. Remember that the monitor
 	   points to the *last* item in the list. */
-      rfp->next = sig->monitor->next;
-      sig->monitor->next = rfp;
-      sig->monitor = rfp;
+      rfp->sig = sig;
+      rfp->next = 0;
+      sig->mlast->next = rfp;
 }
 
 /*
@@ -157,9 +155,32 @@ int vpi_remove_cb(vpiHandle ref)
       assert(ref->vpi_type->type_code == vpiCallback);
 
       if (rfp->ev) {
+
 	      /* callbacks attached to events are easy. */
 	    vpip_sim_cancel_event(rfp->ev);
 
+      } else if (rfp->sig) {
+
+	      /* callbacks to signals need to be removed from the
+		 signal's list of monitor callbacks. */
+	    struct __vpiSignal*sig = rfp->sig;
+
+	    if (sig->mfirst == rfp) {
+		  sig->mfirst = rfp->next;
+		  if (sig->mfirst == 0)
+			sig->mlast = 0;
+		  rfp->next = 0;
+		  rfp->sig = 0;
+	    } else {
+		  struct __vpiCallback*cur = sig->mfirst;
+		  while (cur->next != rfp) {
+			assert(cur->next);
+			cur = cur->next;
+		  }
+		  cur->next = rfp->next;
+		  if (cur->next == 0)
+			sig->mlast = cur;
+	    }
       } else {
 	    assert(0);
       }
@@ -170,6 +191,9 @@ int vpi_remove_cb(vpiHandle ref)
 
 /*
  * $Log: vpi_callback.c,v $
+ * Revision 1.7  2000/03/31 07:08:39  steve
+ *  allow cancelling of cbValueChange events.
+ *
  * Revision 1.6  2000/02/23 02:56:56  steve
  *  Macintosh compilers do not support ident.
  *
diff --git a/vvm/vpi_priv.h b/vvm/vpi_priv.h
index f766d4910..70dd8b8bc 100644
--- a/vvm/vpi_priv.h
+++ b/vvm/vpi_priv.h
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: vpi_priv.h,v 1.13 2000/03/25 05:02:24 steve Exp $"
+#ident "$Id: vpi_priv.h,v 1.14 2000/03/31 07:08:39 steve Exp $"
 #endif
 
 /*
@@ -127,7 +127,11 @@ struct __vpiCallback {
       struct __vpiHandle base;
       struct t_cb_data cb_data;
 
+	/* Set this value if I'm pending in the event queue. */
       struct vpip_event*ev;
+	/* Set this value if I'm waiting for a value change on a signal*/
+      struct __vpiSignal*sig;
+
       struct __vpiCallback*next;
 };
 
@@ -205,7 +209,8 @@ struct __vpiSignal {
       vpip_bit_t*bits;
       unsigned nbits;
 	/* monitors are added here. */
-      struct __vpiCallback*monitor;
+      struct __vpiCallback*mfirst;
+      struct __vpiCallback*mlast;
 };
 
 
@@ -337,6 +342,9 @@ extern int vpip_finished();
 
 /*
  * $Log: vpi_priv.h,v $
+ * Revision 1.14  2000/03/31 07:08:39  steve
+ *  allow cancelling of cbValueChange events.
+ *
  * Revision 1.13  2000/03/25 05:02:24  steve
  *  signal bits are referenced at run time by the vpiSignal struct.
  *
diff --git a/vvm/vpi_signal.c b/vvm/vpi_signal.c
index c9a95e20a..c52a83634 100644
--- a/vvm/vpi_signal.c
+++ b/vvm/vpi_signal.c
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: vpi_signal.c,v 1.8 2000/03/25 05:02:25 steve Exp $"
+#ident "$Id: vpi_signal.c,v 1.9 2000/03/31 07:08:39 steve Exp $"
 #endif
 
 # include  "vpi_priv.h"
@@ -82,7 +82,8 @@ vpiHandle vpip_make_net(struct __vpiSignal*ref, const char*name,
       ref->name = name;
       ref->bits = b;
       ref->nbits = nb;
-      ref->monitor = 0;
+      ref->mfirst = 0;
+      ref->mlast  = 0;
       return &(ref->base);
 }
 
@@ -103,12 +104,16 @@ vpiHandle vpip_make_reg(struct __vpiSignal*ref, const char*name,
       ref->name = name;
       ref->bits = b;
       ref->nbits = nb;
-      ref->monitor = 0;
+      ref->mfirst = 0;
+      ref->mlast  = 0;
       return &(ref->base);
 }
 
 /*
  * $Log: vpi_signal.c,v $
+ * Revision 1.9  2000/03/31 07:08:39  steve
+ *  allow cancelling of cbValueChange events.
+ *
  * Revision 1.8  2000/03/25 05:02:25  steve
  *  signal bits are referenced at run time by the vpiSignal struct.
  *