From: Ulf Brosziewski <ulf.brosziewski@t-online.de>
Subject: wsconsctl: keep wsmouse parameters in sync
To: "tech@openbsd.org" <tech@openbsd.org>
Date: Mon, 16 Sep 2024 23:12:08 +0200

This patch fixes a bug in the 'mousecfg' part of wsconsctl, which can
lead to some display errors if wsconsctl commands are constructed in
a somewhat unusual way.  When wsconsctl fields that are linked to more
than one wsmouse parameter are being changed and subsequently read
within a single command, stale values are read from the mousecfg buffer:

$ wsconsctl mouse.tp.edges
mouse.tp.edges=0.0,0.5,0.0,0.5
$ wsconsctl mouse.tp.edges=1,2,3,4 mouse.tp.edges
mouse.tp.edges -> 1.0,2.0,3.0,4.0
mouse.tp.edges=0.0,0.5,0.0,4.0
$ wsconsctl mouse.tp.edges
mouse.tp.edges=1.0,2.0,3.0,4.0

Obviously, there is no reason to chain WRITE and READ operations in
this way, but it's possible.

OK?


Index: mousecfg.c
===================================================================
RCS file: /cvs/src/sbin/wsconsctl/mousecfg.c,v
retrieving revision 1.10
diff -u -p -r1.10 mousecfg.c
--- mousecfg.c	2 Jul 2023 21:44:04 -0000	1.10
+++ mousecfg.c	16 Sep 2024 20:16:56 -0000
@@ -222,8 +222,10 @@ mousecfg_put_field(int fd, struct wsmous
 	    || (err = ioctl(fd, WSMOUSEIO_GETPARAMS, field)))
 		return err;

-	for (i = 0; i < field->nparams; i++)
+	for (i = 0; i < field->nparams; i++) {
+		n = index_of(field->params[i].key);
 		cfg_buffer[n].value = field->params[i].value;
+	}

 	return (0);
 }