X-Git-Url: https://git.xinqibao.xyz/slock.git/blobdiff_plain/55e827af0fb94f6c2b9e76a7bfe7e98cf697dc7b..a6dc051e3744ce5b14c54d2d246d3e8258207e76:/slock.c

diff --git a/slock.c b/slock.c
index d2c3729..4531f95 100644
--- a/slock.c
+++ b/slock.c
@@ -60,28 +60,20 @@ die(const char *errstr, ...)
 
 #ifdef __linux__
 #include <fcntl.h>
-#include <linux/oom.h>
 
 static void
 dontkillme(void)
 {
 	int fd;
-	int length;
-	char value[64];
 
 	fd = open("/proc/self/oom_score_adj", O_WRONLY);
-	if (fd < 0 && errno == ENOENT)
+	if (fd < 0 && errno == ENOENT) {
 		return;
-
-	/* convert OOM_SCORE_ADJ_MIN to string for writing */
-	length = snprintf(value, sizeof(value), "%d\n", OOM_SCORE_ADJ_MIN);
-
-	/* bail on truncation */
-	if (length >= sizeof(value))
-		die("buffer too small\n");
-
-	if (fd < 0 || write(fd, value, length) != length || close(fd) != 0)
-		die("cannot disable the out-of-memory killer for this process\n");
+	}
+	if (fd < 0 || write(fd, "-1000\n", (sizeof("-1000\n") - 1)) !=
+	    (sizeof("-1000\n") - 1) || close(fd) != 0) {
+		die("can't tame the oom-killer. is suid or sgid set?\n");
+	}
 }
 #endif
 
@@ -230,7 +222,7 @@ lockscreen(Display *dpy, int screen)
 	XSetWindowAttributes wa;
 	Cursor invisible;
 
-	if (dpy == NULL || screen < 0 || !(lock = malloc(sizeof(Lock))))
+	if (!running || dpy == NULL || screen < 0 || !(lock = malloc(sizeof(Lock))))
 		return NULL;
 
 	lock->screen = screen;
@@ -253,52 +245,42 @@ lockscreen(Display *dpy, int screen)
 	XMapRaised(dpy, lock->win);
 	if (rr)
 		XRRSelectInput(dpy, lock->win, RRScreenChangeNotifyMask);
+
+	/* Try to grab mouse pointer *and* keyboard, else fail the lock */
 	for (len = 1000; len; len--) {
 		if (XGrabPointer(dpy, lock->root, False, ButtonPressMask | ButtonReleaseMask | PointerMotionMask,
 		    GrabModeAsync, GrabModeAsync, None, invisible, CurrentTime) == GrabSuccess)
 			break;
 		usleep(1000);
 	}
-	if (running && len) {
+	if (!len) {
+		fprintf(stderr, "slock: unable to grab mouse pointer for screen %d\n", screen);
+	} else {
 		for (len = 1000; len; len--) {
-			if (XGrabKeyboard(dpy, lock->root, True, GrabModeAsync, GrabModeAsync, CurrentTime) == GrabSuccess)
-				break;
+			if (XGrabKeyboard(dpy, lock->root, True, GrabModeAsync, GrabModeAsync, CurrentTime) == GrabSuccess) {
+				/* everything fine, we grabbed both inputs */
+				XSelectInput(dpy, lock->root, SubstructureNotifyMask);
+				return lock;
+			}
 			usleep(1000);
 		}
+		fprintf(stderr, "slock: unable to grab keyboard for screen %d\n", screen);
 	}
-
-	running &= (len > 0);
-	if (!running) {
-		unlockscreen(dpy, lock);
-		lock = NULL;
-	} else {
-		XSelectInput(dpy, lock->root, SubstructureNotifyMask);
-	}
-
-	return lock;
-}
-
-static void
-usage(void)
-{
-	fprintf(stderr, "usage: slock [-v|POST_LOCK_CMD]\n");
-	exit(1);
+	/* grabbing one of the inputs failed */
+	running = 0;
+	unlockscreen(dpy, lock);
+	return NULL;
 }
 
 int
-main(int argc, char **argv) {
+main(int argc, char **argv)
+{
 #ifndef HAVE_BSD_AUTH
 	const char *pws;
 #endif
 	Display *dpy;
 	int screen;
 
-	if ((argc == 2) && !strcmp("-v", argv[1]))
-		die("slock-%s, © 2006-2015 slock engineers\n", VERSION);
-
-	if ((argc == 2) && !strcmp("-h", argv[1]))
-		usage();
-
 #ifdef __linux__
 	dontkillme();
 #endif