From: Stuart Henderson <stu@spacehopper.org>
Subject: Re: w3m -dump_extra segfault
To: Theo Buehler <tb@theobuehler.org>
Cc: ports@openbsd.org, jon@fineman.me
Date: Mon, 16 Sep 2024 10:43:03 +0100

On 2024/09/15 22:15, Theo Buehler wrote:
> See https://marc.info/?l=openbsd-misc&m=172641752723332&w=2 for
> background. In short: 'w3m -dump_extra https://lobste.rs' crashes and
> that breaks this emacs plugin.
> 
> The below reverts the code change from
> 
> https://git.sr.ht/~rkta/w3m/commit/e933cf831f32fd4cf763c64aa60e51dbf025ec94
> 
> and makes lobste.rs, duckduckgo and google work with M-x w3m-browse-url
> in emacs. The problem is that the hack results in loadSomething() being
> called with a NULL loadproc, which it doesn't know how to handle. No
> idea how this was supposed to work...
> 
> Thankfully the FreeBSD w3m maintainer posted a very detailed analysis to
> https://todo.sr.ht/~rkta/w3m/59
> 
> While the below diff makes the reported sites work, it may well break
> other sites.

I use w3m regularly, though mostly with files from disk rather than
over http (it's my default viewer for text/html in mutt) and I don't
recall using it with -dump_source/-dump_extra.

I can confirm the problem with -dump_source (unless using -o
auto_uncompress=true) and -dump_extra (with/without auto_uncompress)
and that the revert patch fixes it. If the patch breaks other sites,
at least it should be no worse than before.

>              So I'm unsure what the best course of action is. I can
> commit this workaround, but maybe someone who is interested in using
> w3m (from within emacs or not) could keep an eye on the issue and port
> the proper fix (if upstream finds one).

OK.

> Index: Makefile
> ===================================================================
> RCS file: /cvs/ports/www/w3m/Makefile,v
> diff -u -p -r1.105 Makefile
> --- Makefile	18 Aug 2024 11:11:45 -0000	1.105
> +++ Makefile	15 Sep 2024 19:58:31 -0000
> @@ -4,6 +4,7 @@ C=		5ae3ef7cb20cd2209629ac0508c05206fd0d
>  DIST_TUPLE=	srht rkta w3m $C .
>  WRKDIST=	${WRKDIR}/w3m-$C
>  DISTNAME=	w3m-0.5.3pl20240810
> +REVISION=	0
>  
>  CATEGORIES=	www
>  
> Index: patches/patch-file_c
> ===================================================================
> RCS file: patches/patch-file_c
> diff -N patches/patch-file_c
> --- /dev/null	1 Jan 1970 00:00:00 -0000
> +++ patches/patch-file_c	15 Sep 2024 19:59:09 -0000
> @@ -0,0 +1,15 @@
> +Revert e933cf831f32fd4cf763c64aa60e51dbf025ec94.
> +See also https://todo.sr.ht/~rkta/w3m/59
> +
> +Index: file.c
> +--- file.c.orig
> ++++ file.c
> +@@ -2263,8 +2263,6 @@ loadGeneralFile(char *path, ParsedURL *volatile curren
> +     }
> +     else if (w3m_dump & DUMP_FRAME)
> + 	return NULL;
> +-    else
> +-	proc = NULL;
> + 
> +     if (t_buf == NULL)
> + 	t_buf = newBuffer(INIT_BUFFER_WIDTH);
>