From edeaf32967396f6480e092603142bfc6b8dc9889 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Fri, 27 Dec 1991 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1991-12-27

---
 port/devpipe.c | 34 +++++++++++++++-------------------
 port/stream.c  |  9 +--------
 2 files changed, 16 insertions(+), 27 deletions(-)

diff --git a/port/devpipe.c b/port/devpipe.c
index 32e43143d29a42832e785349b623ba1fbcbae6bf..39cde7a41fa7d8f2f15519407925b5b89f98a7fb 100644
--- a/port/devpipe.c
+++ b/port/devpipe.c
@@ -13,7 +13,7 @@ typedef struct Pipe	Pipe;
 struct Pipe
 {
 	Ref;
-	int	debug;
+	QLock;
 	Pipe	*next;
 };
 
@@ -88,6 +88,7 @@ pipeattach(char *spec)
 	unlock(&pipealloc);
 
 	c->qid = (Qid){CHDIR|STREAMQID(2*(p - pipealloc.pipe), 0), 0};
+	c->dev = 0;
 	return c;
 }
 
@@ -150,21 +151,18 @@ pipeopen(Chan *c, int omode)
 	}
 
 	p = &pipealloc.pipe[STREAMID(c->qid.path)/2];
-	remote = 0;
 	if(waserror()){
-		unlock(p);
-		if(remote)
-			streamclose1(remote);
+		qunlock(p);
 		nexterror();
 	}
-	lock(p);
+	qlock(p);
 	streamopen(c, &pipeinfo);
 	local = c->stream;
 	if(local->devq->ptr == 0){
 		/*
-		 *  First stream opened, create the other end also
+		 *  first open, create the other end also
 		 */
-		remote = streamnew(c->type, c->dev, STREAMID(c->qid.path)^1, &pipeinfo, 1);
+		remote = streamnew(c->type, c->dev, STREAMID(c->qid.path)^1, &pipeinfo,1);
 
 		/*
 		 *  connect the device ends of both streams
@@ -173,15 +171,13 @@ pipeopen(Chan *c, int omode)
 		remote->devq->ptr = local;
 		local->devq->other->next = remote->devq;
 		remote->devq->other->next = local->devq;
-
+	} else if(local->opens == 1){
 		/*
-		 *  increment the inuse count to reflect the
-		 *  pointer from the other stream.
+		 *  keep other side around till last close of this side
 		 */
-		if(streamenter(local)<0)
-			panic("pipeopen");
+		streamenter(local->devq->ptr);
 	}
-	unlock(p);
+	qunlock(p);
 	poperror();
 
 	c->mode = omode&~OTRUNC;
@@ -220,14 +216,16 @@ pipeclose(Chan *c)
 	p = &pipealloc.pipe[STREAMID(c->qid.path)/2];
 
 	/*
-	 *  take care of associated streams
+	 *  take care of local and remote streams
 	 */
 	if(c->stream){
+		qlock(p);
 		remote = c->stream->devq->ptr;
-		if(streamclose(c) <= 0){
+		if(streamclose(c) == 0){
 			if(remote)
 				streamexit(remote, 0);
 		}
+		qunlock(p);
 	}
 
 	/*
@@ -284,8 +282,7 @@ pipeiput(Queue *q, Block *bp)
 }
 
 /*
- *  send the block to the other side without letting the connection
- *  disappear in mid put.
+ *  send the block to the other side
  */
 static void
 pipeoput(Queue *q, Block *bp)
@@ -300,7 +297,6 @@ static void
 pipestclose(Queue *q)
 {
 	Block *bp;
-	Stream *remote;
 
 	/*
 	 *  point to the bit-bucket and let any in-progress
diff --git a/port/stream.c b/port/stream.c
index cd203a0a32f9dc4991ea9d738116d2bcc4e7bfa0..6d211e6f5a9d580fbed3c6b0f84815caae2178ca 100644
--- a/port/stream.c
+++ b/port/stream.c
@@ -962,22 +962,17 @@ streamclose1(Stream *s)
 	Queue *q, *nq;
 	Block *bp;
 	int rv;
-	char err[ERRLEN];
 
 	/*
 	 *  decrement the reference count
 	 */
 	qlock(s);
-	*err = 0;
 	if(s->opens == 1){
 		/*
 		 *  descend the stream closing the queues
 		 */
 		for(q = s->procq; q; q = q->next){
-			if(waserror()){
-				if(*err == 0)
-					strncpy(err, u->error, ERRLEN-1);
-			} else {
+			if(!waserror()){
 				if(q->info->close)
 					(*q->info->close)(q->other);
 				poperror();
@@ -1006,8 +1001,6 @@ streamclose1(Stream *s)
 	 */
 	streamexit(s, 1);
 	qunlock(s);
-	if(*err)
-		errors(err);
 	return rv;
 }
 int