From 393b646a9877dee2b1dba8d0471ff26656baf9a1 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Thu, 10 Apr 1997 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1997-04-10

---
 port/devcons.c | 20 +++++++++++++++++++-
 port/qio.c     | 24 ++++++++++++------------
 2 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/port/devcons.c b/port/devcons.c
index 3d12046395b6d57bcd9b22c6d8108cab4c506f58..2fd45a16fee655f5c69c0770ba59ed5dcb075de6 100644
--- a/port/devcons.c
+++ b/port/devcons.c
@@ -351,6 +351,7 @@ enum{
 	Qcons,
 	Qconsctl,
 	Qcputime,
+	Qdrivers,
 	Qhz,
 	Qkey,
 	Qhostdomain,
@@ -369,7 +370,7 @@ enum{
 	Quser,
 };
 
-Dirtab consdir[]={
+static Dirtab consdir[]={
 	"authenticate",	{Qauth},	0,		0666,
 	"authcheck",	{Qauthcheck},	0,		0666,
 	"authenticator", {Qauthent},	0,		0666,
@@ -377,6 +378,7 @@ Dirtab consdir[]={
 	"cons",		{Qcons},	0,		0660,
 	"consctl",	{Qconsctl},	0,		0220,
 	"cputime",	{Qcputime},	6*NUMSIZE,	0444,
+	"drivers",	{Qdrivers},	0,		0644,
 	"hostdomain",	{Qhostdomain},	DOMLEN,		0664,
 	"hostowner",	{Qhostowner},	NAMELEN,	0664,
 	"hz",		{Qhz},		NUMSIZE,	0666,
@@ -395,6 +397,11 @@ Dirtab consdir[]={
  	"user",		{Quser},	NAMELEN,	0666,
 };
 
+enum
+{
+	MBS	=	1024,
+};
+
 ulong	boottime;		/* seconds since epoch at boot */
 
 long
@@ -664,6 +671,17 @@ consread(Chan *c, void *buf, long n, ulong offset)
 	case Qrandom:
 		return randomread(buf, n);
 
+	case Qdrivers:
+		b = malloc(MBS);
+		if(b == nil)
+			error(Enomem);
+		n = 0;
+		for(i = 0; devtab[i] != nil; i++)
+			n += snprint(b+n, MBS-n, "#%C %s\n", devtab[i]->dc,  devtab[i]->name);
+		n = readstr(offset, buf, n, b);
+		free(b);
+		return n;
+
 	default:
 		print("consread %lux\n", c->qid);
 		error(Egreg);
diff --git a/port/qio.c b/port/qio.c
index dab1669e8c0928fe6e63b771b5dc1f0f594db906..a59960211a9c508799d9890be0f3afd310438d60 100644
--- a/port/qio.c
+++ b/port/qio.c
@@ -489,7 +489,7 @@ qdiscard(Queue *q, int len)
 	Block *b;
 	int dowakeup, n, sofar;
 
-	lock(q);
+	ilock(q);
 	for(sofar = 0; sofar < len; sofar += n){
 		b = q->bfirst;
 		if(b == nil)
@@ -513,7 +513,7 @@ qdiscard(Queue *q, int len)
 	} else
 		dowakeup = 0;
 
-	unlock(q);
+	iunlock(q);
 
 	if(dowakeup)
 		wakeup(&q->wr);
@@ -530,13 +530,13 @@ qconsume(Queue *q, void *vp, int len)
 	uchar *p = vp;
 
 	/* sync with qwrite */
-	lock(q);
+	ilock(q);
 
 	for(;;) {
 		b = q->bfirst;
 		if(b == 0){
 			q->state |= Qstarve;
-			unlock(q);
+			iunlock(q);
 			return -1;
 		}
 		QDEBUG checkb(b, "qconsume 1");
@@ -564,7 +564,7 @@ qconsume(Queue *q, void *vp, int len)
 	} else
 		dowakeup = 0;
 
-	unlock(q);
+	iunlock(q);
 
 	if(dowakeup)
 		wakeup(&q->wr);
@@ -631,19 +631,19 @@ qproduce(Queue *q, void *vp, int len)
 
 	/* sync with qread */
 	dowakeup = 0;
-	lock(q);
+	ilock(q);
 
 	/* no waiting receivers, room in buffer? */
 	if(q->len >= q->limit){
 		q->state |= Qflow;
-		unlock(q);
+		iunlock(q);
 		return -1;
 	}
 
 	/* save in buffer */
 	b = iallocb(len);
 	if(b == 0){
-		unlock(q);
+		iunlock(q);
 		return 0;
 	}
 	memmove(b->wp, p, len);
@@ -662,7 +662,7 @@ qproduce(Queue *q, void *vp, int len)
 		q->state &= ~Qstarve;
 		dowakeup = 1;
 	}
-	unlock(q);
+	iunlock(q);
 
 	if(dowakeup)
 		wakeup(&q->rr);
@@ -683,13 +683,13 @@ qcopy(Queue *q, int len, ulong offset)
 
 	nb = allocb(len);
 
-	lock(q);
+	ilock(q);
 
 	/* go to offset */
 	b = q->bfirst;
 	for(sofar = 0; ; sofar += n){
 		if(b == nil){
-			unlock(q);
+			iunlock(q);
 			return nb;
 		}
 		n = BLEN(b);
@@ -715,7 +715,7 @@ qcopy(Queue *q, int len, ulong offset)
 		n = BLEN(b);
 		p = b->rp;
 	}
-	unlock(q);
+	iunlock(q);
 
 	return nb;
 }