From f6996f990518824f910ee31a730a47632ba721af Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Mon, 22 Jan 1996 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1996-01-22

---
 port/devtinyfs.c | 44 ++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 40 insertions(+), 4 deletions(-)

diff --git a/port/devtinyfs.c b/port/devtinyfs.c
index 883afb55405040c7135dee0f180a04bf1204bdce..d9a028fa9793d35683c442a2787a707f7f2efe33 100644
--- a/port/devtinyfs.c
+++ b/port/devtinyfs.c
@@ -17,12 +17,23 @@ enum{
 	Qmedium,
 };
 
+typedef struct FS FS;
 
-struct {
+struct FS {
 	QLock;
+	Ref	r;
+	int	dev;
+	FS	*next;
 	Chan	*c;
-	Dirtab	file[Nfile+1];
+	Dirtab	*file;
 	int	nfile;
+	int	maxfile;
+};
+
+struct {
+	QLock;
+	FS	*l;
+	int	hidev;
 } tinyfs;
 
 void
@@ -46,9 +57,34 @@ tinyfsinit(void)
 Chan *
 tinyfsattach(char *spec)
 {
-	c = namec((char*)arg[0], Aopen, arg[1], 0);
+	FS *fs, **l;
+	Chan *c, *cc;
+
+	cc = namec((char*)arg[0], Aopen, arg[1], 0);
+	qlock(&tinyfs);
+	l = &tinyfs.l;
+	for(fs = tinyfs.l; fs != 0; fs = fs->next){
+		if(eqchan(c, fs->c))
+			break;
+		l = &(fs->next);
+	}
+	if(fs){
+		incref(&fs->r);
+		qunlock(&tinyfs);
+		close(cc);
+	} else {
+		fs = smalloc(sizeof(*fs));
+		*l = fs;
+		fs->c = cc;
+		incref(&fs->r);
+		qunlock(&tinyfs);
+	}
+
+	c = devattach('E', spec);
+	c->aux = fs;
+	c->dev = fs->dev;
 
-	return devattach('E', spec);
+	return c;
 }
 
 Chan *