[9front] screenlock

[Stuart Morrow <morrow.stuart@gmail.com>]

Would like to get this in before release as it all-but-fixes the
horrible visual bug of the green border.

String becomes stringbg so we have guaranteed max contrast in case the
user changes the picture. (If you don't change the picture, it's
white-on-black-on-black (sic) and you would never notice the change.)

(Still puzzled and bothered by the getwindow'ing version.)

--- /mnt/git/object/be36c092ac061a04065720e98e5849130487be7f/tree/sys/src/cmd/screenlock.c
+++ sys/src/cmd/screenlock.c
@@ -119,14 +119,17 @@
 void
 top(void*)
 {
-	int fd;
+	int fd, n;
+	char buf[128];

-	if((fd = open("/dev/wctl", OWRITE)) < 0)
+	if((fd = open("/dev/wctl", ORDWR)) < 0)
 		return;

 	for(;;){
-		write(fd, "current", 7);
-		sleep(500);
+		n = read(fd, buf, sizeof buf);
+		if(n > 48)
+			if(strstr(buf+48, "notcurrent"))
+				write(fd, "current", 7);
 	}
 }

@@ -186,7 +189,7 @@
 		tm = localtime(time(&blank));
 		s = smprint("user %s at %d:%02.2d", getuser(), tm->hour, tm->min);
 		p = subpt(p, Pt(stringwidth(font, "m") * strlen(s) / 2, 0));
-		string(screen, p, screen->display->white, ZP, font, s);
+		stringbg(screen, p, display->white, ZP, font, s, display->black, ZP);
 	}
 	flushimage(display, 1);