From eda43993dd44522ae609ec1af1629c7051f8d25a Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Sat, 4 Jul 1992 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1992-07-04

---
 port/devbit.c   | 59 +++++++++++++++++++++++++++++++++++++++++--------
 port/devcons.c  |  3 +++
 port/portfns.h  |  1 +
 ss/faultsparc.c | 12 ++++++++--
 4 files changed, 64 insertions(+), 11 deletions(-)

diff --git a/port/devbit.c b/port/devbit.c
index df7c14113c81772a76acfb78e1307b8a4ff819ec..94ec62b7e8b497d39e070dd0e1215d5296a7e431 100644
--- a/port/devbit.c
+++ b/port/devbit.c
@@ -172,6 +172,43 @@ Dirtab bitdir[]={
 #define	NINFO	8192	/* max chars per subfont; sanity check only */
 #define	HDR	3
 
+void
+bitdebug(void)
+{
+	int i;
+	long l;
+	Arena *a;
+
+	l = 0;
+	for(i=0; i<bit.narena; i++){
+		a = &bit.arena[i];
+		if(a->words){
+			l += a->nwords;
+			print("%d: %ld used; %ld total\n", i,
+				(a->wfree-a->words)*sizeof(ulong),
+				a->nwords*sizeof(ulong));
+		}
+	}
+	print("arena: %ld words\n", l*sizeof(ulong));
+	l = 0;
+	for(i=0; i<bit.nmap; i++)
+		if(bit.map[i])
+			l++;
+	print("%d bitmaps ", l);
+	l = 0;
+	for(i=0; i<bit.nfont; i++)
+		if(bit.font[i])
+			l++;
+	print("%d fonts ", l);
+	l = 0;
+	for(i=0; i<bit.nsubfont; i++)
+		if(bit.subfont[i]){
+			print("%d: %lux %lux ", i, bit.subfont[i]->qid[0], bit.subfont[i]->qid[1]);
+			l++;
+		}
+	print("%d subfonts\n", l);
+}
+
 void
 bitreset(void)
 {
@@ -891,8 +928,10 @@ bitwrite(Chan *c, void *va, long n, ulong offset)
 				if(j == i)
 					continue;
 				tf = bit.subfont[j];
-				if(tf && tf->qid[0]==f->qid[0] && tf->qid[1]==f->qid[1])
+				if(tf && tf->qid[0]==f->qid[0] && tf->qid[1]==f->qid[1]){
 					f->qid[0] = ~0;	/* uncached */
+					break;
+				}
 			}
 			f->ref = 1;
 			v = BGSHORT(p+5);
@@ -1173,7 +1212,8 @@ bitwrite(Chan *c, void *va, long n, ulong offset)
 
 		case 'v':
 			/*
-			 * clear font cache and bitmap
+			 * clear font cache and bitmap.
+			 * if error, font is unchanged.
 			 *	'v'		1
 			 *	id		2
 			 *	ncache		2
@@ -1185,6 +1225,14 @@ bitwrite(Chan *c, void *va, long n, ulong offset)
 			t = BGSHORT(p+3);
 			if(t<0 || v<0 || v>=bit.nfont || (ff=bit.font[v])==0)
 				error(Ebadblt);
+			x = BGSHORT(p+5);
+			i = bitalloc(Rect(0, 0, t*x, ff->height), ff->ldepth);
+			/* now committed */
+			if(ff->b)
+				bitfree(ff->b);
+			ff->b = bit.map[i];
+			bit.map[i] = 0;	/* disconnect it from GBitmap space */
+			ff->width = x;
 			/*
 			 * memset not necessary but helps avoid
 			 * confusion if the cache is mishandled by the
@@ -1197,13 +1245,6 @@ bitwrite(Chan *c, void *va, long n, ulong offset)
 				ff->cache = smalloc(t*sizeof(ff->cache[0]));
 				ff->ncache = t;
 			}
-			if(ff->b)
-				bitfree(ff->b);
-			ff->width = BGSHORT(p+5);
-			ff->b = 0;
-			i = bitalloc(Rect(0, 0, t*ff->width, ff->height), ff->ldepth);
-			ff->b = bit.map[i];
-			bit.map[i] = 0;	/* disconnect it from GBitmap space */
 			p += 7;
 			m -= 7;
 			break;
diff --git a/port/devcons.c b/port/devcons.c
index de36bde7c5626203d1891dda1f6a6101a14924c4..c60e34841ff490fedcf7277022efa73628e30359 100644
--- a/port/devcons.c
+++ b/port/devcons.c
@@ -231,6 +231,9 @@ echo(Rune r, char *buf, int n)
 		case 'x':
 			xsummary();
 			break;
+		case 'b':
+			bitdebug();
+			break;
 		case 'd':
 			consdebug();
 			return;
diff --git a/port/portfns.h b/port/portfns.h
index f6910f293d445cc52c6e7f52b07b028a660bf1c2..bc661b4714f0b00bdc0213bb434c73d713d6edea 100644
--- a/port/portfns.h
+++ b/port/portfns.h
@@ -2,6 +2,7 @@ void		alarmkproc(void*);
 Block*		allocb(ulong);
 int		anyready(void);
 Image*		attachimage(int, Chan*, ulong, ulong);
+void		bitdebug(void);
 int		blen(Block *);
 int		bround(Block *, int);
 void		buzz(int, int);
diff --git a/ss/faultsparc.c b/ss/faultsparc.c
index 1a735778438a5e7ede7b8186955c17f14f0f48aa..f0e443cfc055961671a9784529e17a68ecef910c 100644
--- a/ss/faultsparc.c
+++ b/ss/faultsparc.c
@@ -6,13 +6,20 @@
 #include	"ureg.h"
 #include	"../port/error.h"
 
+enum
+{
+	SE_WRITE	= 0x8000,
+	SE_INV		= 0x0080,
+	SE_PROT		= 0x0040,
+};
+
 void
 faultsparc(Ureg *ur)
 {
 	ulong addr, badvaddr;
 	char buf[ERRLEN];
 	int user, read;
-	ulong tbr;
+	ulong tbr, ser;
 
 	tbr = (ur->tbr&0xFFF)>>4;
 	addr = ur->pc;			/* assume instr. exception */
@@ -22,7 +29,8 @@ faultsparc(Ureg *ur)
 		 * According to the book, this isn't good enough.  We'll see.
 		 */
 		addr = getw2(SEVAR);
-		if(getw2(SER) & 0x8000)
+		ser = getw2(SER);
+		if(ser&(SE_WRITE|SE_PROT))
 			read = 0;
 	}
 	spllo();