slock

commit 7afc5518aa5a0f912947afa32b3c30f621a3be63
parent 36d211ccf95e48fdaf376740e19ee4a2e985df3f
Author: Jul <jul@9o.is>
Date:   Thu,  5 Feb 2026 05:57:57 -0500

prevent unlocking until timer expires with -t flag

Diffstat:
M
config.def.h
 | 
4
++++
M
config.h
 | 
4
++++
M
config.mk
 | 
5
+++--
M
slock.1
 | 
10
++++++++++
M
slock.c
 | 
103
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-

5 files changed, 123 insertions(+), 3 deletions(-)
diff --git a/config.def.h b/config.def.h
@@ -10,3 +10,7 @@ static const char *colorname[NUMCOLS] = {
 
 /* treat a cleared input like a wrong password (color) */
 static const int failonclear = 1;
+
+static const char *font = "monospace-16";
+static const char *fontcolor = "white";
+static const char *timer_message = "Locked:";
diff --git a/config.h b/config.h
@@ -10,3 +10,7 @@ static const char *colorname[NUMCOLS] = {
 
 /* treat a cleared input like a wrong password (color) */
 static const int failonclear = 1;
+
+static const char *font = "Fira Mono-18";
+static const char *fontcolor = "#E3E3E3";
+static const char *timer_message = "LOCKED!";
diff --git a/config.mk b/config.mk
@@ -9,10 +9,11 @@ MANPREFIX = ${PREFIX}/share/man
 
 X11INC = /usr/X11R6/include
 X11LIB = /usr/X11R6/lib
+FT2INC = /usr/include/freetype2
 
 # includes and libs
-INCS = -I. -I/usr/include -I${X11INC}
-LIBS = -L/usr/lib -lc -lcrypt -L${X11LIB} -lX11 -lXext -lXrandr
+INCS = -I. -I/usr/include -I${X11INC} -I${FT2INC}
+LIBS = -L/usr/lib -lc -lcrypt -L${X11LIB} -lX11 -lXext -lXrandr -lXft
 
 # flags
 CPPFLAGS = -DVERSION=\"${VERSION}\" -D_DEFAULT_SOURCE -DHAVE_SHADOW_H
diff --git a/slock.1 b/slock.1
@@ -7,6 +7,7 @@
 .Sh SYNOPSIS
 .Nm
 .Op Fl v
+.Op Fl t Ar seconds
 .Op Ar cmd Op Ar arg ...
 .Sh DESCRIPTION
 .Nm
@@ -17,6 +18,10 @@ is executed after the screen has been locked.
 .Pp
 The options are as follows:
 .Bl -tag -width Ds
+.It Fl t Ar seconds
+Lock the screen for a minimum of
+.Ar seconds
+before allowing password entry. The screen will prevent unlocking until the timer expires.
 .It Fl v
 Print version information to stdout and exit.
 .El
@@ -25,7 +30,12 @@ Print version information to stdout and exit.
 .Sh EXAMPLES
 $
 .Nm
+Lock the screen normally.
+.Pp
+$
+.Nm
 /usr/sbin/s2ram
+Lock the screen before suspending to RAM.
 .Sh SECURITY CONSIDERATIONS
 To make sure a locked screen can not be bypassed by switching VTs
 or killing the X server with Ctrl+Alt+Backspace, it is recommended
diff --git a/slock.c b/slock.c
@@ -12,6 +12,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <time.h>
 #include <unistd.h>
 #include <spawn.h>
 #include <sys/types.h>
@@ -19,6 +20,7 @@
 #include <X11/keysym.h>
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
+#include <X11/Xft/Xft.h>
 
 #include "arg.h"
 #include "util.h"
@@ -37,6 +39,9 @@ struct lock {
 	Window root, win;
 	Pixmap pmap;
 	unsigned long colors[NUMCOLS];
+	XftColor xftcolor;
+	XftDraw *xftdraw;
+	XftFont *xftfont;
 };
 
 struct xrandr {
@@ -48,6 +53,84 @@ struct xrandr {
 #include "config.h"
 
 static void
+drawtext(Display *dpy, struct lock *lock, const char *text)
+{
+	int w, h, x, y;
+	XGlyphInfo extents;
+
+	if (!lock->xftdraw || !lock->xftfont)
+		return;
+
+	XftTextExtentsUtf8(dpy, lock->xftfont,
+			(const XftChar8 *)text, strlen(text), &extents);
+
+	w = extents.width;
+	h = lock->xftfont->ascent + lock->xftfont->descent;
+	x = (DisplayWidth(dpy, lock->screen) - w) / 2;
+	y = (DisplayHeight(dpy, lock->screen) - h) / 2 + lock->xftfont->ascent;
+
+	XftDrawStringUtf8(lock->xftdraw, &lock->xftcolor, lock->xftfont, x, y,
+			(const XftChar8 *)text, strlen(text));
+}
+
+static void
+initxftfont(Display *dpy, struct lock *lock)
+{
+	lock->xftdraw = XftDrawCreate(dpy, lock->win,
+			DefaultVisual(dpy, lock->screen),
+			DefaultColormap(dpy, lock->screen));
+
+	lock->xftfont = XftFontOpenName(dpy, lock->screen, font);
+
+	if (!lock->xftfont) {
+		lock->xftfont = XftFontOpen(dpy, lock->screen,
+				XFT_FAMILY, XftTypeString, "fixed",
+				XFT_SIZE, XftTypeDouble, 16.0,
+				NULL);
+	}
+
+	XftColorAllocName(dpy, DefaultVisual(dpy, lock->screen),
+			DefaultColormap(dpy, lock->screen), fontcolor, &lock->xftcolor);
+}
+
+static void
+locktimer(Display *dpy, struct lock **locks, int nscreens, int timeout)
+{
+	char timer_text[32];
+	int m, s, screen, remaining;
+	time_t lock_time;
+	XEvent ev;
+
+	lock_time = time(NULL);
+	remaining = timeout - (time(NULL) - lock_time);
+
+	for (screen = 0; screen < nscreens; screen++)
+		XRaiseWindow(dpy, locks[screen]->win);
+
+	while (XPending(dpy))
+		XNextEvent(dpy, &ev);
+
+	while (remaining > 0) {
+		for (screen = 0; screen < nscreens; screen++) {
+			m = remaining / 60;
+			s = remaining % 60;
+			snprintf(timer_text, sizeof(timer_text), "%s %d:%02d remaining", timer_message, m, s);
+			XClearWindow(dpy, locks[screen]->win);
+			drawtext(dpy, locks[screen], timer_text);
+		}
+
+		while (XPending(dpy))
+			XNextEvent(dpy, &ev);
+
+		usleep(50000); // 50ms
+		remaining = timeout - (time(NULL) - lock_time);
+	}
+
+	for (screen = 0; screen < nscreens; screen++)
+		XClearWindow(dpy, locks[screen]->win);
+}
+
+static void
 die(const char *errstr, ...)
 {
 	va_list ap;
@@ -279,6 +362,7 @@ lockscreen(Display *dpy, struct xrandr *rr, int screen)
 			if (rr->active)
 				XRRSelectInput(dpy, lock->win, RRScreenChangeNotifyMask);
 
+			initxftfont(dpy, lock);
 			XSelectInput(dpy, lock->root, SubstructureNotifyMask);
 			return lock;
 		}
@@ -304,7 +388,7 @@ lockscreen(Display *dpy, struct xrandr *rr, int screen)
 static void
 usage(void)
 {
-	die("usage: slock [-v] [cmd [arg ...]]\n");
+	die("usage: slock [-v] [-t seconds] [cmd [arg ...]]\n");
 }
 
 int
@@ -318,11 +402,15 @@ main(int argc, char **argv) {
 	const char *hash;
 	Display *dpy;
 	int s, nlocks, nscreens;
+	int timeout = 0;
 
 	ARGBEGIN {
 	case 'v':
 		puts("slock-"VERSION);
 		return 0;
+	case 't':
+		timeout = atoi(EARGF(usage()));
+		break;
 	default:
 		usage();
 	} ARGEND
@@ -389,8 +477,21 @@ main(int argc, char **argv) {
 		}
 	}
 
+	if (timeout > 0)
+		locktimer(dpy, locks, nscreens, timeout);
+
 	/* everything is now blank. Wait for the correct password */
 	readpw(dpy, &rr, locks, nscreens, hash);
 
+	/* Cleanup Xft resources */
+	for (s = 0; s < nscreens; s++) {
+		if (locks[s]) {
+			if (locks[s]->xftfont)
+				XftFontClose(dpy, locks[s]->xftfont);
+			if (locks[s]->xftdraw)
+				XftDrawDestroy(locks[s]->xftdraw);
+		}
+	}
+
 	return 0;
 }