From e0a7598d1362df2a1ccef46f8b448e91ad3e3e4c Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Sun, 16 Aug 1992 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1992-08-16

---
 port/devbit.c | 49 +++++++++++++++++++++++++++----------------------
 power/clock.c |  2 +-
 ss/screen.c   |  2 +-
 3 files changed, 29 insertions(+), 24 deletions(-)

diff --git a/port/devbit.c b/port/devbit.c
index 29c49ac9a983f453d53fd2d39f10ea1aaa3f5410..3a4df96c8527d82060c43fbcdb71be77405ad853 100644
--- a/port/devbit.c
+++ b/port/devbit.c
@@ -463,7 +463,7 @@ bitread(Chan *c, void *va, long n, ulong offset)
 {
 	uchar *p, *q;
 	long miny, maxy, t, x, y;
-	ulong l, v, nw, ws, rv, gv, bv;
+	ulong l, nw, ws, rv, gv, bv;
 	int off, j;
 	Fontchar *i;
 	GBitmap *src;
@@ -525,12 +525,13 @@ bitread(Chan *c, void *va, long n, ulong offset)
 		p = va;
 		for(y=miny; y<maxy; y++){
 			q = (uchar*)gaddr(&gscreen, Pt(0, y));
-			for(x=0; x<l; x++,p++,q++){
-				v = *q;
-				if(flipping)
-					v = ~v;
-				BPLONG(p, v);
-			}
+			memmove(p, q, l);
+			if(flipping)
+				/* is screen, so must be word aligned */
+				for(x=0; x<l; x+=sizeof(ulong),p+=sizeof(ulong))
+					*(ulong*)p ^= ~0;
+			else
+				p += l;
 			n += l;
 		}
 		return n;
@@ -718,12 +719,13 @@ bitread(Chan *c, void *va, long n, ulong offset)
 		for(y=miny; y<maxy; y++){
 			q = (uchar*)gaddr(src, Pt(src->r.min.x, y));
 			q += (src->r.min.x&((sizeof(ulong))*ws-1))/ws;
-			if(bit.rid == 0)
-				for(x=0; x<l; x++,p++,q++)
-					BPLONG(p, ~*q);
+			memmove(p, q, l);
+			if(bit.rid==0 && flipping)
+				/* is screen, so must be word aligned */
+				for(x=0; x<l; x+=sizeof(ulong),p+=sizeof(ulong))
+					*(ulong*)p ^= ~0;
 			else
-				for(x=0; x<l; x++)
-					*p++ = *q++;
+				p += l;
 			n += l;
 		}
 		if(off)
@@ -739,9 +741,10 @@ bitread(Chan *c, void *va, long n, ulong offset)
 long
 bitwrite(Chan *c, void *va, long n, ulong offset)
 {
-	uchar *p, *q;
+	uchar *p, *q, *oq;
 	long m, v, miny, maxy, t, x, y;
 	ulong l, nw, ws, rv, q0, q1;
+	ulong *lp;
 	int off, isoff, i, j, ok;
 	Point pt, pt1, pt2;
 	Rectangle rect;
@@ -1391,14 +1394,16 @@ bitwrite(Chan *c, void *va, long n, ulong offset)
 				isoff = 1;
 			}
 			for(y=miny; y<maxy; y++){
-				q = (uchar*)gaddr(dst, Pt(dst->r.min.x, y));
-				q += (dst->r.min.x&((sizeof(ulong))*ws-1))/ws;
-				if(v == 0 && flipping)	/* flip bits */
-					for(x=0; x<l; x++)
-						*q++ = ~(*p++);
-				else
-					for(x=0; x<l; x++)
-						*q++ = *p++;
+				oq = (uchar*)gaddr(dst, Pt(dst->r.min.x, y));
+				q = oq + (dst->r.min.x&((sizeof(ulong))*ws-1))/ws;
+				memmove(q, p, l);
+				if(v==0 && flipping){	/* flip bits */
+					/* we know it's all word aligned */
+					lp = (ulong*)oq;
+					for(x=0; x<l; x+=sizeof(ulong))
+						*lp++ ^= ~0;
+				}
+				p += l;
 				m -= l;
 			}
 			break;
@@ -1414,7 +1419,7 @@ bitwrite(Chan *c, void *va, long n, ulong offset)
 				error(Ebadblt);
 			pt1.x = BGLONG(p+1);
 			pt1.y = BGLONG(p+5);
-/*			if(!eqpt(mouse.xy, pt1))*/{
+			if(ptinrect(pt1, gscreen.r)){
 				mouse.xy = pt1;
 				mouse.track = 1;
 				mouseclock();
diff --git a/power/clock.c b/power/clock.c
index ff3b8c37a46f9e05157e15a7623c380a2ac6a017..541b578e315abfc2997daa6f3df1c99f49f354bb 100644
--- a/power/clock.c
+++ b/power/clock.c
@@ -114,7 +114,7 @@ clock(Ureg *ur)
 		}
 		checkalarms();
 		kproftimer(ur->pc);
-		if(u && (ur->status&IEP) && u->p && u->p->state==Running){
+		if(u && (ur->status&IEP) && u->p->state==Running){
 			if(anyready()){
 				if(u->p->hasspin)
 					u->p->hasspin = 0;	/* just in case */
diff --git a/ss/screen.c b/ss/screen.c
index ba626fcaa73ffb984b847d0d10cc9f9631388c09..8171ad867d6f3fd33a93af5a1ba2613f5c30bf23 100644
--- a/ss/screen.c
+++ b/ss/screen.c
@@ -49,7 +49,7 @@ struct screens
 }screens[] = {
 	{ "bwtwo", 1152, 900, 0, 0x400000 },
 	{ "cgsix", 1152, 900, 3, 0x200000 },
-	{ "cgthree", 1152, 900, 3, 0x200000 },
+	{ "cgthree", 1152, 900, 3, 0x200000 },	/* PURE GUESS! */
 	0
 };