[hackers] [slock] Re-introduce the waiting loop for input grabbing || Quentin Rameau

From: <git_AT_suckless.org>
Date: Fri, 2 Sep 2016 11:49:05 +0200 (CEST)

commit e378f735d857f7da124177e3540912d920be5022
Author: Quentin Rameau <quinq_AT_fifth.space>
AuthorDate: Thu Sep 1 13:46:51 2016 +0200
Commit: Markus Teich <markus.teich_AT_stusta.mhn.de>
CommitDate: Fri Sep 2 10:50:32 2016 +0200

    Re-introduce the waiting loop for input grabbing
    
    We actually “need” to wait a little for input to be released before
    locking for cases where slock is spawned from other graphical
    applications using keybindings.
    This undoes the misbehaviour I introduced in c2f9757, sorry for the mess.

diff --git a/slock.c b/slock.c
index 4980325..97c7489 100644
--- a/slock.c
+++ b/slock.c
_AT_@ -223,6 +223,7 @@ unlockscreen(Display *dpy, Lock *lock)
                 return;
 
         XUngrabPointer(dpy, CurrentTime);
+ XUngrabKeyboard(dpy, CurrentTime);
         XFreeColors(dpy, DefaultColormap(dpy, lock->screen), lock->colors, NUMCOLS, 0);
         XFreePixmap(dpy, lock->pmap);
         XDestroyWindow(dpy, lock->win);
_AT_@ -241,7 +242,7 @@ static Lock *
 lockscreen(Display *dpy, int screen)
 {
         char curs[] = {0, 0, 0, 0, 0, 0, 0, 0};
- int i;
+ int i, ptgrab, kbgrab;
         Lock *lock;
         XColor color, dummy;
         XSetWindowAttributes wa;
_AT_@ -268,30 +269,45 @@ lockscreen(Display *dpy, int screen)
         invisible = XCreatePixmapCursor(dpy, lock->pmap, lock->pmap, &color, &color, 0, 0);
         XDefineCursor(dpy, lock->win, invisible);
 
- /* Try to grab mouse pointer *and* keyboard, else fail the lock */
- if (XGrabPointer(dpy, lock->root, False, ButtonPressMask |
- ButtonReleaseMask | PointerMotionMask, GrabModeAsync, GrabModeAsync,
- None, invisible, CurrentTime) != GrabSuccess) {
- fprintf(stderr, "slock: unable to grab mouse pointer for screen %d\n", screen);
- running = 0;
- unlockscreen(dpy, lock);
- return NULL;
- }
+ /* Try to grab mouse pointer *and* keyboard for 600ms, else fail the lock */
+ for (i = 6, ptgrab = kbgrab = -1; i; --i) {
+ if (ptgrab != GrabSuccess) {
+ ptgrab = XGrabPointer(dpy, lock->root, False,
+ ButtonPressMask | ButtonReleaseMask |
+ PointerMotionMask, GrabModeAsync,
+ GrabModeAsync, None, invisible, CurrentTime);
+ }
+ if (kbgrab != GrabSuccess) {
+ kbgrab = XGrabKeyboard(dpy, lock->root, True,
+ GrabModeAsync, GrabModeAsync, CurrentTime);
+ }
 
- if (XGrabKeyboard(dpy, lock->root, True, GrabModeAsync, GrabModeAsync,
- CurrentTime) != GrabSuccess) {
- fprintf(stderr, "slock: unable to grab keyboard for screen %d\n", screen);
- running = 0;
- unlockscreen(dpy, lock);
- return NULL;
- }
+ /* input is grabbed: we can lock the screen */
+ if (ptgrab == GrabSuccess && kbgrab == GrabSuccess) {
+ XMapRaised(dpy, lock->win);
+ if (rr)
+ XRRSelectInput(dpy, lock->win, RRScreenChangeNotifyMask);
+
+ XSelectInput(dpy, lock->root, SubstructureNotifyMask);
+ return lock;
+ }
 
- XMapRaised(dpy, lock->win);
- if (rr)
- XRRSelectInput(dpy, lock->win, RRScreenChangeNotifyMask);
+ /* retry on AlreadyGrabbed but fail on other errors */
+ if ((ptgrab != AlreadyGrabbed && ptgrab != GrabSuccess) ||
+ (kbgrab != AlreadyGrabbed && kbgrab != GrabSuccess))
+ break;
 
- XSelectInput(dpy, lock->root, SubstructureNotifyMask);
- return lock;
+ usleep(100000);
+ }
+
+ /* we couldn't grab all input: fail out */
+ if (ptgrab != GrabSuccess)
+ fprintf(stderr, "slock: unable to grab mouse pointer for screen %d\n", screen);
+ if (kbgrab != GrabSuccess)
+ fprintf(stderr, "slock: unable to grab keyboard for screen %d\n", screen);
+ running = 0;
+ unlockscreen(dpy, lock);
+ return NULL;
 }
 
 static void
Received on Fri Sep 02 2016 - 11:49:05 CEST