Re: Bug/misfeature with autoloaded TRAPxxx functions

[Peter Stephenson <pws@xxxxxxx>]

Bart Schaefer wrote:
> I worry that there's a race condition between setting sigtrapped[signum]
> and actually adding the function node.

Well, I would guess there are various possible races, many of which were
already in the TRAP function handling.

I suppose this fixes the one you are worried about.

> And what happens if the fucntion
> fails to load?  Does sigtrapped[signum] get cleared somewhere else?

No, but it's consistent with other failed functions.

% autoload spooble
% spooble
zsh: spooble: function definition file not found
% spooble
zsh: spooble: function definition file not found
% autoload TRAPZERR
% false
zsh: TRAPZERR: function definition file not found
% false
zsh: TRAPZERR: function definition file not found

With the current behaviour of retrying, clearing the trap doesn't look
like the right thing to do.

However, there seems to be a bug somewhere anyway.

% autoload TRAPZERR
% echo <TAB>
...
% false
zsh: segmentation fault (core dumped)  ./zsh

Happens whether or not the autoload was successful, interestingly.
Doesn't happen if you successfully autoload the trap before completion
(or define TRAPZERR inline).  Symptom is an empty state->prog->shf in
execautofn.

Also, $functions don't show TRAP functions.

Index: builtin.c
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/builtin.c,v
retrieving revision 1.117
diff -u -r1.117 builtin.c
--- builtin.c	20 Apr 2004 12:57:35 -0000	1.117
+++ builtin.c	21 Apr 2004 17:23:27 -0000
@@ -2515,12 +2515,13 @@
 	    shf = (Shfunc) zshcalloc(sizeof *shf);
 	    shf->flags = on;
 	    shf->funcdef = mkautofn(shf);
+	    shfunctab->addnode(shfunctab, ztrdup(*argv), shf);
 
 	    if (!strncmp(*argv, "TRAP", 4) &&
 		(signum = getsignum(*argv + 4)) != -1) {
 		if (settrap(signum, shf->funcdef)) {
-		    freeeprog(shf->funcdef);
-		    zfree(shf, sizeof(*shf));
+		    shfunctab->removenode(shfunctab, *argv);
+		    shfunctab->freenode((HashNode)shf);
 		    returnval = 1;
 		    ok = 0;
 		}
@@ -2528,12 +2529,9 @@
 		    sigtrapped[signum] |= ZSIG_FUNC;
 	    }
 
-	    if (ok) {
-		shfunctab->addnode(shfunctab, ztrdup(*argv), shf);
-		if (OPT_ISSET(ops,'X') &&
-		    eval_autoload(shf, shf->nam, ops, func))
-		    returnval = 1;
-	    }
+	    if (ok && OPT_ISSET(ops,'X') &&
+		eval_autoload(shf, shf->nam, ops, func))
+		returnval = 1;
 	} else
 	    returnval = 1;
     }
-- 
Peter Stephenson <pws@xxxxxxx>                  Software Engineer
CSR Ltd., Science Park, Milton Road,
Cambridge, CB4 0WH, UK                          Tel: +44 (0)1223 692070


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