devdraw: get rid of softscreen==0xa110c hack and make attachscreen() return Memdata*

all screen implementations use a Memimage* internally
for the framebuffer, so we can return a shared reference
to its Memdata structure in attachscreen() instead of
a framebuffer data pointer.

this eleminates the softscreen == 0xa110c hack as we
always use shared Memdata* now.

2 files changed, 7 insertions, 6 deletions

diff --git a/sys/src/9/sgi/screen.c b/sys/src/9/sgi/screen.c
index 6d1829315..c5b96837c 100644
--- a/sys/src/9/sgi/screen.c
+++ b/sys/src/9/sgi/screen.c
@@ -600,19 +600,20 @@ screeninit(void)
 	mouseaccelerate(3);
 }
 
-uchar*
+Memdata*
 attachscreen(Rectangle *r, ulong *chan, int* d, int *width, int *softscreen)
 {
+	if(gscreen == nil)
+		return nil;
+
 	*r = gscreen->r;
 	*d = gscreen->depth;
 	*chan = gscreen->chan;
 	*width = gscreen->width;
+	*softscreen = 1;
 
-	/* make devdraw use gscreen->data */
-	*softscreen = 0xa110c;
 	gscreen->data->ref++;
-
-	return gscreen->data->bdata;
+	return gscreen->data;
 }
 
 void
diff --git a/sys/src/9/sgi/screen.h b/sys/src/9/sgi/screen.h
index 0633fbe74..b5ab1c9ba 100644
--- a/sys/src/9/sgi/screen.h
+++ b/sys/src/9/sgi/screen.h
@@ -26,7 +26,7 @@ extern void mouseredraw(void);
 /* screen.c */
 extern void	blankscreen(int);
 extern void	flushmemscreen(Rectangle);
-extern uchar*	attachscreen(Rectangle*, ulong*, int*, int*, int*);
+extern Memdata*	attachscreen(Rectangle*, ulong*, int*, int*, int*);
 extern void	cursoron(void);
 extern void	cursoroff(void);
 extern void	setcursor(Cursor*);