[prev in list] [next in list] [prev in thread] [next in thread] 

List:       dash
Subject:    Re: [BUG] Here-document redirection with vi/emacs on
From:       Harald van Dijk <harald () gigawatt ! nl>
Date:       2017-06-29 23:33:29
Message-ID: d343eac0-b110-609b-6f7e-aa85e29f9091 () gigawatt ! nl
[Download RAW message or body]

On 27/06/17 16:29, Zando Fardones wrote:
> Hello,
> 
> I think I've found a bug when using the here-document redirection in
> an interactive shell. What basically happens is that you can't see the
> command output if you set the "vi" or "emacs" options.

That's not quite what happens: the here-document contents got lost, so 
there is no command output to see. Nice find.

The problem is that getprompt() is implicitly called by el_gets(). This 
messes with the memory used by the parser to store the here-document's 
contents. In the non-emacs/vi case, the prompt is explicitly written by 
setprompt(), which wraps the getprompt() call in a 
pushstackmark()/popstackmark() pair to restore the state so that parsing 
can continue. But when getprompt() is called by el_gets(), it knows 
nothing about this.

The whole call to el_gets() can be surrounded by another 
pushstackmark()/popstackmark() pair to solve the problem, as attached.

Cheers,
Harald van Dijk

["dash-libedit-heredoc.patch" (text/x-patch)]

--- a/src/input.c
+++ b/src/input.c
@@ -147,8 +147,12 @@ retry:
 		static const char *rl_cp;
 		static int el_len;
 
-		if (rl_cp == NULL)
+		if (rl_cp == NULL) {
+			struct stackmark smark;
+			pushstackmark(&smark, stackblocksize());
 			rl_cp = el_gets(el, &el_len);
+			popstackmark(&smark);
+		}
 		if (rl_cp == NULL)
 			nr = 0;
 		else {

--
To unsubscribe from this list: send the line "unsubscribe dash" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[prev in list] [next in list] [prev in thread] [next in thread]