From e8d3b6a8553a5f79a00b959f9a6e7211edadc424 Mon Sep 17 00:00:00 2001
From: Kurt Miller <kurt@cvs.openbsd.org>
Date: Tue, 17 Oct 2006 20:57:29 +0000
Subject: Don't grab _FD_LOCK and queue up behind other threads as this can
 potentially block indefinitely. Instead just protect against fd state
 transitions and perform the _thread_sys_shutdown(). Fixes deadlock reported
 by Tero Koskinen <tero.koskinen at iki.fi>. okay kettenis@

---
 lib/libpthread/uthread/uthread_shutdown.c | 35 ++++++++++++-------------------
 1 file changed, 13 insertions(+), 22 deletions(-)

(limited to 'lib')

diff --git a/lib/libpthread/uthread/uthread_shutdown.c b/lib/libpthread/uthread/uthread_shutdown.c
index b3219ec73a5..e8f3e776afb 100644
--- a/lib/libpthread/uthread/uthread_shutdown.c
+++ b/lib/libpthread/uthread/uthread_shutdown.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uthread_shutdown.c,v 1.4 2003/02/14 02:34:16 marc Exp $	*/
+/*	$OpenBSD: uthread_shutdown.c,v 1.5 2006/10/17 20:57:28 kurt Exp $	*/
 /*
  * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
  * All rights reserved.
@@ -43,31 +43,22 @@ int
 shutdown(int fd, int how)
 {
 	int             ret;
+	struct fd_table_entry *entry;
 
-	switch (how) {
-	case 0:
-		if ((ret = _FD_LOCK(fd, FD_READ, NULL)) == 0) {
+	ret = _thread_fd_table_init(fd, FD_INIT_UNKNOWN, NULL);
+	if (ret == 0) {
+		entry = _thread_fd_table[fd];
+		 
+		_SPINLOCK(&entry->lock);
+		if (entry->state == FD_ENTRY_OPEN) {
 			ret = _thread_sys_shutdown(fd, how);
-			_FD_UNLOCK(fd, FD_READ);
+		} else {
+			ret = -1;
+			errno = EBADF;
 		}
-		break;
-	case 1:
-		if ((ret = _FD_LOCK(fd, FD_WRITE, NULL)) == 0) {
-			ret = _thread_sys_shutdown(fd, how);
-			_FD_UNLOCK(fd, FD_WRITE);
-		}
-		break;
-	case 2:
-		if ((ret = _FD_LOCK(fd, FD_RDWR, NULL)) == 0) {
-			ret = _thread_sys_shutdown(fd, how);
-			_FD_UNLOCK(fd, FD_RDWR);
-		}
-		break;
-	default:
-		errno =  EBADF;
-		ret = -1;
-		break;
+		_SPINUNLOCK(&entry->lock);
 	}
+
 	return (ret);
 }
 #endif
-- 
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