From abf0ec9b801664f280f4c7da37110ac638086fdc Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Sat, 3 Feb 1996 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1996-02-03

---
 pc/main.c        | 45 ++++++++++++++++++++++++++++------
 port/devtinyfs.c | 63 ++++++++++++++++++++++++++++++------------------
 2 files changed, 77 insertions(+), 31 deletions(-)

diff --git a/pc/main.c b/pc/main.c
index 35ad98756e646913c27479e5de8645231db43247..7383a7a3187b5e824fe332d42daff2ce92979d50 100644
--- a/pc/main.c
+++ b/pc/main.c
@@ -354,29 +354,60 @@ romscan(void)
 	}
 }
 
+static int
+getcfields(char *lp, char **fields, int n, char sep)
+{
+	int i;
+
+	for(i=0; lp && *lp && i<n; i++){
+		while(*lp == sep)
+			*lp++=0;
+		if(*lp == 0)
+			break;
+		fields[i]=lp;
+		while(*lp && *lp != sep){
+			if(*lp == '\\' && *(lp+1) == '\n')
+				*lp++ = ' ';
+			lp++;
+		}
+	}
+	return i;
+}
+
 void
 confinit(void)
 {
 	long x, i, j, n;
 	int pcnt;
 	ulong ktop;
-	char *cp;
-	char *line[MAXCONF];
+	char *cp, *line[MAXCONF], *p, *q;
 	extern int defmaxmsg;
 
 	pcnt = 0;
 
-
 	/*
 	 *  parse configuration args from dos file plan9.ini
 	 */
 	cp = BOOTARGS;	/* where b.com leaves its config */
 	cp[BOOTARGSLEN-1] = 0;
-	n = getfields(cp, line, MAXCONF, "\n");
+
+	/*
+	 * Strip out '\r', change '\t' -> ' '.
+	 */
+	p = cp;
+	for(q = cp; *q; q++){
+		if(*q == '\r')
+			continue;
+		if(*q == '\t')
+			*q = ' ';
+		*p++ = *q;
+	}
+	*p = 0;
+
+	n = getcfields(cp, line, MAXCONF, '\n');
 	for(j = 0; j < n; j++){
-		cp = strchr(line[j], '\r');
-		if(cp)
-			*cp = 0;
+		if(*line[j] == '#')
+			continue;
 		cp = strchr(line[j], '=');
 		if(cp == 0)
 			continue;
diff --git a/port/devtinyfs.c b/port/devtinyfs.c
index eb2c4845d0fce7842956aa5d8f8099ccf907f15c..9f12616f9cd80d1e8fe45275597bd866a04e068c 100644
--- a/port/devtinyfs.c
+++ b/port/devtinyfs.c
@@ -28,6 +28,9 @@ enum{
 
 	Notapin=		0xffff,
 	Notabno=		0xffff,
+
+	Fcreating=	1,
+	Frmonclose=	2,
 };
 
 /* representation of a Tdir on medium */
@@ -57,7 +60,7 @@ struct Tfile {
 	ushort	bno;
 	ushort	dbno;
 	ushort	pin;
-	char	creating;
+	uchar	flag;
 	ulong	length;
 };
 
@@ -271,7 +274,7 @@ newfile(Tfs *fs, char *name)
 		expand(fs);
 	}
 
-	f->creating = 1;
+	f->flag = Fcreating;
 	f->dbno = Notabno;
 	f->bno = mapalloc(fs);
 
@@ -553,20 +556,31 @@ tinyfsclose(Chan *c)
 	if(c->qid.path != CHDIR){
 		f = &fs->f[c->qid.path];
 		f->r--;
-		if(f->r == 0 && f->creating){
-			/* remove all other files with this name */
-			for(i = 0; i < fs->fsize; i++){
-				nf = &fs->f[i];
-				if(f == nf)
-					continue;
-				if(strcmp(nf->name, f->name) == 0)
-					freefile(fs, nf, Notabno);
+		if(f->r == 0){
+			if(f->creating){
+				/* remove all other files with this name */
+				for(i = 0; i < fs->fsize; i++){
+					nf = &fs->f[i];
+					if(f == nf)
+						continue;
+					if(strcmp(nf->name, f->name) == 0){
+						if(nf->r)
+							nf->flag |= Frmonclose;
+						else
+							freefile(fs, nf, Notabno);
+					}
+				}
+				f->flag &= ~(Frmonclose|Fcreating);
 			}
+			if(f->flag & Frmonclose){
+				freefile(fs, f, Notabno);
 		}
 	}
 
 	/* dereference fs and remove on zero refs */
 	fs->r--;
+	unlock(fs);
+	qlock(&tinyfs);
 	if(fs->ref == 0){
 		for(l = &fs->l; *l;){
 			if(*l == fs){
@@ -575,30 +589,31 @@ tinyfsclose(Chan *c)
 			}
 			l = &(*l)->next;
 		}
-		for(f = fs->f; f; f = nf){
-			nf = f->next;
-			free(f);
-		}
+		free(fs-f);
 		free(fs->map);
 		close(fs->c);
-		free(fs);
+		memset(fs, 0, sizeof(*fs));
 	}
-	unlock(fs);
 	qunlock(&tinyfs);
 }
 
 long
 tinyfsread(Chan *c, void *a, long n, ulong offset)
 {
-	switch(c->qid.path & ~CHDIR){
-	case Qdir:
+	Tfs *fs;
+	Tfile *f;
+	int sofar, i;
+
+	if(c->qid.path & CHDIR)
 		return devdirread(c, a, n, tinyfstab, Ntinyfstab, tinyfsgen);
-	case Qdata:
-		break;
-	default:
-		n=0;
-		break;
-	}
+
+	fs = tinyfs.fs[c->dev];
+	f = &fs->f[c->qid.path];
+	if(offset >= f->length)
+		return 0;
+	if(n + offset >= f->length)
+		n = f->length - offset;
+
 	return n;
 }