PATCH: 4.1.0: `builtin' with disabled builtin.

PATCH: 4.1.0: `builtin' with disabled builtin.

[Peter Stephenson]

It used to be possible to get round the fact that a builtin was disabled by
putting `builtin' in front of it, which somehow disappeared when I wasn't
looking.  I think the old behaviour is useful and harmless.  This is based
on my assumption that `disable' is to stop a builtin polluting the general
namespace, not to stop anyone executing it who needs it.  Does anyone
have any worries about this?

Index: Doc/Zsh/builtins.yo
===================================================================
RCS file: /cvsroot/zsh/zsh/Doc/Zsh/builtins.yo,v
retrieving revision 1.30
diff -u -r1.30 builtins.yo
--- Doc/Zsh/builtins.yo	2001/06/14 09:49:02	1.30
+++ Doc/Zsh/builtins.yo	2001/06/15 22:01:17
@@ -130,7 +130,8 @@
 )
 findex(builtin)
 item(tt(builtin) var(name) [ var(args) ... ])(
-Executes the builtin var(name), with the given var(args).
+Executes the builtin var(name), with the given var(args).  This can
+be used even if var(name) has been disabled.
 )
 alias(bye)(exit)
 module(cap)(zsh/cap)
Index: Src/exec.c
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/exec.c,v
retrieving revision 1.28
diff -u -r1.28 exec.c
--- Src/exec.c	2001/05/28 09:00:22	1.28
+++ Src/exec.c	2001/06/15 22:01:36
@@ -1714,7 +1714,9 @@
 		is_shfunc = 1;
 		break;
 	    }
-	    if (!(hn = builtintab->getnode(builtintab, cmdarg))) {
+	    if (!(hn = (cflags & BINF_BUILTIN) ?
+		  builtintab->getnode2(builtintab, cmdarg) :
+		  builtintab->getnode(builtintab, cmdarg))) {
 		checked = !(cflags & BINF_BUILTIN);
 		break;
 	    }
@@ -1829,7 +1831,9 @@
 		is_shfunc = 1;
 		break;
 	    }
-	    if (!(hn = builtintab->getnode(builtintab, cmdarg))) {
+	    if (!(hn = (cflags & BINF_BUILTIN) ?
+		  builtintab->getnode2(builtintab, cmdarg) :
+		  builtintab->getnode(builtintab, cmdarg))) {
 		if (cflags & BINF_BUILTIN) {
 		    zwarn("no such builtin: %s", cmdarg, 0);
 		    lastval = 1;

-- 
Peter Stephenson <pws@pwstephenson.fsnet.co.uk>
Work: pws@csr.com
Web: http://www.pwstephenson.fsnet.co.uk

Re: PATCH: 4.1.0: `builtin' with disabled builtin.

[Bart Schaefer]

On Jun 16, 12:06am, Peter Stephenson wrote:
} Subject: PATCH: 4.1.0: `builtin' with disabled builtin.
}
} It used to be possible to get round the fact that a builtin was disabled by
} putting `builtin' in front of it, which somehow disappeared when I wasn't
} looking.

That's been gone since sometime in 2.5 or 2.6, whenever it was that real
hash tables replaced linked lists for command lookup.  I don't think it
has ever worked in any 3.x version.

} I think the old behaviour is useful and harmless.

Unless one is trying to use disable to create a restricted shell.  Then
one has to disable builtin as well, which might not be desirable for
other reasons.

} Does anyone have any worries about this?

I don't feel strongly one way or the other; I have a slight preference
for the v >= 3.0 behavior rather than the v <= 2.4 behavior, but not so
much as to carry on a lengthy disagreement about it.


-- 
Bart Schaefer                                 Brass Lantern Enterprises
http://www.well.com/user/barts              http://www.brasslantern.com

Zsh: http://www.zsh.org | PHPerl Project: http://phperl.sourceforge.net   

Re: PATCH: 4.1.0: `builtin' with disabled builtin.

[Oliver Kiddle]

Bart Schaefer wrote:
> 
> On Jun 16, 12:06am, Peter Stephenson wrote:
> }
> } It used to be possible to get round the fact that a builtin was disabled by
> } putting `builtin' in front of it

> } I think the old behaviour is useful and harmless.
> 
> Unless one is trying to use disable to create a restricted shell.  Then
> one has to disable builtin as well, which might not be desirable for

Would it maybe make sense to allow this behaviour except when the
restricted option is set? Basically, I agree with Peter that the `old
behaviour is useful and harmless' except in a restricted shell.

> I don't feel strongly one way or the other;

Neither do I really.

Oliver