From 1c5a5383a1cf3351fe9c80a21cfbc98c5ec4355d Mon Sep 17 00:00:00 2001
From: Yan Doroshenko <yan1994doroshenko@gmail.com>
Date: Fri, 18 Mar 2022 12:28:13 +0100
Subject: [PATCH] Provide a way to set a background image

---
 config.def.h |  5 ++++-
 config.mk    |  2 +-
 slock.c      | 50 +++++++++++++++++++++++++++++++++++++++++++++++---
 3 files changed, 52 insertions(+), 5 deletions(-)

diff --git a/config.def.h b/config.def.h
index 9855e21..eb88b3d 100644
--- a/config.def.h
+++ b/config.def.h
@@ -1,6 +1,6 @@
 /* user and group to drop privileges to */
 static const char *user  = "nobody";
-static const char *group = "nogroup";
+static const char *group = "nobody";
 
 static const char *colorname[NUMCOLS] = {
 	[INIT] =   "black",     /* after initialization */
@@ -10,3 +10,6 @@ static const char *colorname[NUMCOLS] = {
 
 /* treat a cleared input like a wrong password (color) */
 static const int failonclear = 1;
+
+/* Background image path, should be available to the user above */
+static const char* background_image = "";
diff --git a/config.mk b/config.mk
index 74429ae..987819e 100644
--- a/config.mk
+++ b/config.mk
@@ -12,7 +12,7 @@ X11LIB = /usr/X11R6/lib
 
 # includes and libs
 INCS = -I. -I/usr/include -I${X11INC}
-LIBS = -L/usr/lib -lc -lcrypt -L${X11LIB} -lX11 -lXext -lXrandr
+LIBS = -L/usr/lib -lc -lcrypt -L${X11LIB} -lX11 -lXext -lXrandr -lImlib2
 
 # flags
 CPPFLAGS = -DVERSION=\"${VERSION}\" -D_DEFAULT_SOURCE -DHAVE_SHADOW_H
diff --git a/slock.c b/slock.c
index 5ae738c..345a279 100644
--- a/slock.c
+++ b/slock.c
@@ -18,6 +18,7 @@
 #include <X11/keysym.h>
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
+#include <Imlib2.h>
 
 #include "arg.h"
 #include "util.h"
@@ -35,6 +36,7 @@ struct lock {
 	int screen;
 	Window root, win;
 	Pixmap pmap;
+	Pixmap bgmap;
 	unsigned long colors[NUMCOLS];
 };
 
@@ -46,6 +48,8 @@ struct xrandr {
 
 #include "config.h"
 
+Imlib_Image image;
+
 static void
 die(const char *errstr, ...)
 {
@@ -190,9 +194,10 @@ readpw(Display *dpy, struct xrandr *rr, struct lock **locks, int nscreens,
 			color = len ? INPUT : ((failure || failonclear) ? FAILED : INIT);
 			if (running && oldc != color) {
 				for (screen = 0; screen < nscreens; screen++) {
-					XSetWindowBackground(dpy,
-					                     locks[screen]->win,
-					                     locks[screen]->colors[color]);
+                                        if (locks[screen]->bgmap)
+                                                XSetWindowBackgroundPixmap(dpy, locks[screen]->win, locks[screen]->bgmap);
+                                        else
+                                                XSetWindowBackground(dpy, locks[screen]->win, locks[screen]->colors[0]);
 					XClearWindow(dpy, locks[screen]->win);
 				}
 				oldc = color;
@@ -235,6 +240,17 @@ lockscreen(Display *dpy, struct xrandr *rr, int screen)
 	lock->screen = screen;
 	lock->root = RootWindow(dpy, lock->screen);
 
+        if(image)
+        {
+            lock->bgmap = XCreatePixmap(dpy, lock->root, DisplayWidth(dpy, lock->screen), DisplayHeight(dpy, lock->screen), DefaultDepth(dpy, lock->screen));
+            imlib_context_set_display(dpy);
+            imlib_context_set_visual(DefaultVisual(dpy, lock->screen));
+            imlib_context_set_colormap(DefaultColormap(dpy, lock->screen));
+            imlib_context_set_drawable(lock->bgmap);
+            imlib_render_image_on_drawable(0, 0);
+            imlib_free_image();
+        }
+
 	for (i = 0; i < NUMCOLS; i++) {
 		XAllocNamedColor(dpy, DefaultColormap(dpy, lock->screen),
 		                 colorname[i], &color, &dummy);
@@ -251,6 +267,8 @@ lockscreen(Display *dpy, struct xrandr *rr, int screen)
 	                          CopyFromParent,
 	                          DefaultVisual(dpy, lock->screen),
 	                          CWOverrideRedirect | CWBackPixel, &wa);
+        if(lock->bgmap)
+          XSetWindowBackgroundPixmap(dpy, lock->win, lock->bgmap);
 	lock->pmap = XCreateBitmapFromData(dpy, lock->win, curs, 8, 8);
 	invisible = XCreatePixmapCursor(dpy, lock->pmap, lock->pmap,
 	                                &color, &color, 0, 0);
@@ -355,6 +373,32 @@ main(int argc, char **argv) {
 	if (setuid(duid) < 0)
 		die("slock: setuid: %s\n", strerror(errno));
 
+	/* Load picture */
+        Imlib_Image buffer = imlib_load_image(background_image);
+	imlib_context_set_image(buffer);
+        int background_image_width = imlib_image_get_width();
+        int background_image_height = imlib_image_get_height();
+
+        /* Create an image to be rendered */
+	Screen *scr = ScreenOfDisplay(dpy, DefaultScreen(dpy));
+	image = imlib_create_image(scr->width, scr->height);
+        imlib_context_set_image(image);
+
+        /* Fill the image for every X monitor */
+        XRRMonitorInfo	*monitors;
+        int number_of_monitors;
+        monitors = XRRGetMonitors(dpy, RootWindow(dpy, XScreenNumberOfScreen(scr)), True, &number_of_monitors);
+
+        int i;
+        for (i = 0; i < number_of_monitors; i++) {
+            imlib_blend_image_onto_image(buffer, 0, 0, 0, background_image_width, background_image_height, monitors[i].x, monitors[i].y, monitors[i].width, monitors[i].height);
+        }
+
+        /* Clean up */
+        imlib_context_set_image(buffer);
+        imlib_free_image();
+        imlib_context_set_image(image);
+
 	/* check for Xrandr support */
 	rr.active = XRRQueryExtension(dpy, &rr.evbase, &rr.errbase);
 
-- 
2.35.1

