PATCH: parameter module

[Peter Stephenson <pws@xxxxxxxxxxxxxxxxx>]

I spotted some problems with the parameter module.

1. If you call zmodload from a function, the parameters got loaded into
local scope.  Since I use a function load() which calls zmodload, this
confused me.  As the scope of the zmodload is not local, and there is no
typeset to make them appear in local scope, I presume this was not the
intention, but maybe I was wrong.  It might be possible to do some typeset
trickery so that `typeset parameters' gets the parameters special variable
loaded into local scope.  At the moment, I shudder to think what effect
this has(*), but I put a debugging test in createparam() for parameters
that didn't get deleted properly from a local scope.

(*) I thought createparam() was supposed to fail if you did this, and hence
createspecialparam() also, but that doesn't seem to happen.  I don't dare
look at this in case it's a bug.

2. When unloading, $parameters was readonly and complained about it.

3. Trivial fix for a compiler warning about unitialized variables.  I also
added a debugging check for unhandled parameter types:  you never know when
someone's going to change the shell and forget the parameter module.

--- Src/Modules/parameter.c.pm	Thu May 13 17:45:44 1999
+++ Src/Modules/parameter.c	Sat May 15 16:19:37 1999
@@ -50,7 +50,7 @@
     if (!(pm = createparam(name, PM_SPECIAL|PM_REMOVABLE|PM_HASHED)))
 	return NULL;
 
-    pm->level = locallevel;
+    pm->level = pm->old ? locallevel : 0;
     pm->gets.hfn = hashgetfn;
     pm->sets.hfn = hashsetfn;
     pm->unsetfn = stdunsetfn;
@@ -79,7 +79,7 @@
 static char *
 paramtypestr(Param pm)
 {
-    char *val;
+    char *val = NULL;
     int f = pm->flags;
 
     if (!(f & PM_UNSET)) {
@@ -89,6 +89,7 @@
 	case PM_INTEGER: val = "integer"; break;
 	case PM_HASHED:  val = "association"; break;
 	}
+	DPUTS(!val, "BUG: type not handled in parameter");
 	val = dupstring(val);
 	if (f & PM_LEFT)
 	    val = dyncat(val, "-left");
@@ -638,8 +639,10 @@
 
     /* Remove the special parameters if they are still the same. */
 
-    if ((pm = (Param) paramtab->getnode(paramtab, PAR_NAM)) && pm == parpm)
+    if ((pm = (Param) paramtab->getnode(paramtab, PAR_NAM)) && pm == parpm) {
+	pm->flags &= ~PM_READONLY;
 	unsetparam_pm(pm, 0, 1);
+    }
     if ((pm = (Param) paramtab->getnode(paramtab, CMD_NAM)) && pm == cmdpm)
 	unsetparam_pm(pm, 0, 1);
     if ((pm = (Param) paramtab->getnode(paramtab, FUN_NAM)) && pm == funpm)
--- Src/params.c.pm	Thu May 13 17:45:43 1999
+++ Src/params.c	Sat May 15 16:27:47 1999
@@ -572,6 +572,8 @@
 			 gethashnode2(paramtab, name) :
 			 paramtab->getnode(paramtab, name));
 
+	DPUTS(oldpm && oldpm->level > locallevel,
+	      "BUG:  old local parameter not deleteed");
 	if (oldpm && oldpm->level == locallevel) {
 	    if (!(oldpm->flags & PM_UNSET) || (oldpm->flags & PM_SPECIAL)) {
 		oldpm->flags &= ~PM_UNSET;

-- 
Peter Stephenson <pws@xxxxxxxxxxxxxxxxx>       Tel: +39 050 844536
WWW:  http://www.ifh.de/~pws/
Dipartimento di Fisica, Via Buonarroti 2, 56127 Pisa, Italy