The attached patch is code we've used in Xsun for years, and our Sun Ray
people recently hit the same issue again in their Xorg 1.2-based Xnewt
server port. It simply changes the Xserver to always use a filename
containing the display number for xkm output, so that if two servers are
starting at once with the same keymap they don't overwrite or delete
each other's xkm files. While we're probably more likely to hit this
on Sun Ray servers which can have hundreds of X servers running, I think
it could also hit a single user machine with :0 & :1 starting on different
vt's at the same time.
(Of course, the oft-mentioned change of not forking xkbcomp to compile to
xkm would also solve this, but this is a much simpler short-term fix.)
Does this look good to everyone? Anyone know of a reason it would not
be a good idea?
--
-Alan Coopersmith- [EMAIL PROTECTED]
Sun Microsystems, Inc. - X Window System Engineering
>From ba5aed47f241ada8c73b61b3d5e18a1c2ccd268a Mon Sep 17 00:00:00 2001
From: Alan Coopersmith <[EMAIL PROTECTED]>
Date: Wed, 19 Nov 2008 13:44:26 -0800
Subject: [PATCH] Always use server-<display>.xkm to avoid races when multiple
servers start
Previously each server starting ran xkbcomp with the output set to
<keymapname>.xkm, read it, then deleted it - which led to races if
two servers were starting at the same time with the same keymap.
Sun bug #6773816 Xorg uses the same xkm output file for compiled keymap file
<http://bugs.opensolaris.org/bugdatabase/view_bug.do?bug_id=6773816>
---
xkb/ddxLoad.c | 12 ++----------
1 files changed, 2 insertions(+), 10 deletions(-)
diff --git a/xkb/ddxLoad.c b/xkb/ddxLoad.c
index fc49d99..80da963 100644
--- a/xkb/ddxLoad.c
+++ b/xkb/ddxLoad.c
@@ -192,16 +192,8 @@ char *buf = NULL,
keymap[PATH_MAX],xkm_output_dir[PATH_MAX];
#ifdef WIN32
char tmpname[PATH_MAX];
#endif
- if ((names->keymap==NULL)||(names->keymap[0]=='\0')) {
- sprintf(keymap,"server-%s",display);
- }
- else {
- if (strlen(names->keymap) > PATH_MAX - 1) {
- ErrorF("[xkb] name of keymap (%s) exceeds max length\n",
names->keymap);
- return False;
- }
- strcpy(keymap,names->keymap);
- }
+
+ snprintf(keymap, sizeof(keymap), "server-%s", display);
XkbEnsureSafeMapName(keymap);
OutputDirectory(xkm_output_dir, sizeof(xkm_output_dir));
--
1.5.6.5
_______________________________________________
xorg mailing list
[email protected]
http://lists.freedesktop.org/mailman/listinfo/xorg
