screenlock: use initdisplay(2), top the window (thanks stuart morrow)

Screenlock should use libdraw(2) to init the display
and create the window, instead of looking at the screen
file directly. Also, to prevent new windows from popping
up over screenlock, bring it to the top periodically.

1 files changed, 25 insertions, 12 deletions

diff --git a/sys/src/cmd/screenlock.c b/sys/src/cmd/screenlock.c
index 8e3e48de8..9ac9fa064 100644
--- a/sys/src/cmd/screenlock.c
+++ b/sys/src/cmd/screenlock.c
@@ -17,6 +17,7 @@ usage(void)
 	exits("usage");
 }
 
+/* ^D, Delete, Enter, Backspace, ^U */
 void
 readline(char *buf, int nbuf)
 {
@@ -116,27 +117,38 @@ grabmouse(void*)
 }
 
 void
+top(void*)
+{
+	int fd;
+
+	if((fd = open("/dev/wctl", OWRITE)) < 0)
+		return;
+
+	for(;;){
+		write(fd, "current", 7);
+		sleep(500);
+	}
+}
+
+void
 lockscreen(void)
 {
-	enum { Nfld = 5, Fldlen = 12, Cursorlen = 2*4 + 2*2*16, };
+	enum { Cursorlen = 2*4 + 2*2*16 };
 	char *s;
-	char buf[Nfld*Fldlen], *flds[Nfld], newcmd[128], cbuf[Cursorlen];
+	char newcmd[128], cbuf[Cursorlen];
 	int fd, dx, dy;
 	Image *i;
 	Point p;
 	Rectangle r;
 	Tm *tm;
 
-	if((fd = open("/dev/screen", OREAD)) < 0)
-		sysfatal("can't open /dev/screen: %r");
-	if(read(fd, buf, Nfld*Fldlen) != Nfld*Fldlen)
-		sysfatal("can't read /dev/screen: %r");
-	close(fd);
-	buf[sizeof buf-1] = 0;
-	if(tokenize(buf, flds, Nfld) != Nfld)
-		sysfatal("can't tokenize /dev/screen header");
-	snprint(newcmd, sizeof newcmd, "-r %s %s %s %s",
-		flds[1], flds[2], flds[3], flds[4]);
+	display = initdisplay(nil, nil, nil);
+	if(display == nil)
+		sysfatal("can't open /dev/draw: %r");
+	r = display->image->r;
+	snprint(newcmd, sizeof newcmd, "-r %d %d %d %d",
+		r.min.x, r.min.y, r.max.x, r.max.y);
+	closedisplay(display);
 
 	newwindow(newcmd);
 	if((fd = open("/dev/consctl", OWRITE)) >= 0)
@@ -179,6 +191,7 @@ lockscreen(void)
 	flushimage(display, 1);
 
 	/* screen is now open and covered.  grab mouse and hold on tight */
+	procrfork(top, nil, 8*1024, RFFDG);
 	procrfork(grabmouse, nil, 8*1024, RFFDG);
 	procrfork(blanker, nil, 8*1024, RFFDG);