devmouse: refactor screen blanking logic

devmouse controls the screen blanking timeout, so move the
code there avoiding cross calls between modules. the only
function that needs to be provided is blankscreen(), which
gets called with drawlock locked.

the blank timeout is set thru /dev/mousectl now, so kernels
without devvga can set it.

blanking now only happens while /dev/mouse is read. so this
avoids accidentally blanking the screen on cpu servers that
do not have a mouse to unblank it.

1 files changed, 43 insertions, 17 deletions

diff --git a/sys/src/9/port/devmouse.c b/sys/src/9/port/devmouse.c
index c3010b012..74db2587b 100644
--- a/sys/src/9/port/devmouse.c
+++ b/sys/src/9/port/devmouse.c
@@ -53,6 +53,8 @@ enum
 	CMbuttonmap,
 	CMscrollswap,
 	CMswap,
+	CMblank,
+	CMblanktime,
 	CMtwitch,
 	CMwildcard,
 };
@@ -62,7 +64,9 @@ static Cmdtab mousectlmsg[] =
 	CMbuttonmap,	"buttonmap",	0,
 	CMscrollswap,	"scrollswap",	0,
 	CMswap,		"swap",		1,
-	CMtwitch,	"twitch",	0,
+	CMblank,	"blank",	1,
+	CMblanktime,	"blanktime",	2,
+	CMtwitch,	"twitch",	1,
 	CMwildcard,	"*",		0,
 };
 
@@ -71,6 +75,7 @@ Cursorinfo	cursor;
 Cursor		curs;
 
 void	Cursortocursor(Cursor*);
+void	mouseblankscreen(int);
 int	mousechanged(void*);
 void	mouseredraw(void);
 
@@ -96,6 +101,7 @@ static uchar buttonmap[8] = {
 static int mouseswap;
 static int scrollswap;
 static ulong mousetime;
+static ulong blanktime = 30;	/* in minutes; a half hour */
 
 extern Memimage* gscreen;
 
@@ -197,6 +203,7 @@ mouseopen(Chan *c, int omode)
 			error(Einuse);
 		mouse.lastcounter = mouse.counter;
 		mouse.resize = 0;
+		mousetime = seconds();
 		/* wet floor */
 	case Qcursor:
 		incref(&mouse);
@@ -220,6 +227,7 @@ mouseclose(Chan *c)
 		return;
 	case Qmouse:
 		mouse.open = 0;
+		mouseblankscreen(0);
 		/* wet floor */
 	case Qcursor:
 		if(decref(&mouse) != 0)
@@ -259,9 +267,14 @@ mouseread(Chan *c, void *va, long n, vlong off)
 		return n;
 
 	case Qmouse:
-		while(mousechanged(0) == 0)
-			sleep(&mouse.r, mousechanged, 0);
+		while(!mousechanged(nil)){
+			tsleep(&mouse.r, mousechanged, nil, 30*1000);
+			if(blanktime && !mousechanged(nil) &&
+			   (seconds() - mousetime) >= blanktime*60)
+				mouseblankscreen(1);
+		}
 		mousetime = seconds();
+		mouseblankscreen(0);
 
 		ilock(&mouse);
 		if(mouse.ri != mouse.wi)
@@ -399,8 +412,16 @@ mousewrite(Chan *c, void *va, long n, vlong)
 				setbuttonmap(cb->f[1]);
 			break;
 
+		case CMblank:
+			mouseblankscreen(1);
+			break;
+
+		case CMblanktime:
+			blanktime = strtoul(cb->f[1], 0, 0);
+			/* wet floor */
 		case CMtwitch:
-			drawactive(1);
+			mousetime = seconds();
+			mouseblankscreen(0);
 			break;
 
 		case CMwildcard:
@@ -501,6 +522,20 @@ Cursortocursor(Cursor *c)
 	qunlock(&drawlock);
 }
 
+void
+mouseblankscreen(int blank)
+{
+	static int blanked;
+
+	if(blank == blanked)
+		return;
+	qlock(&drawlock);
+	if(blanked != blank){
+		blankscreen(blank);
+		blanked = blank;
+	}
+	qunlock(&drawlock);
+}
 
 static int
 shouldredraw(void*)
@@ -514,22 +549,13 @@ shouldredraw(void*)
 static void
 mouseproc(void*)
 {
-	ulong counter;
-
-	counter = ~0;
 	while(waserror())
 		;
 	for(;;){
-		if(mouse.redraw){
-			mouse.redraw = 0;
-			cursoroff();
-			cursoron();
-		}
-
-		drawactive(mouse.counter != counter);
-		counter = mouse.counter;
-
-		tsleep(&mouse.redrawr, shouldredraw, 0, 20*1000);
+		sleep(&mouse.redrawr, shouldredraw, nil);
+		mouse.redraw = 0;
+		cursoroff();
+		cursoron();
 	}
 }