Add pthread_attr_[sg]etguardsize() to match rthread, including manpages

Bump lib minor

ok otto@ kurt@ marc@; doc review by jmc@

18 files changed, 269 insertions, 39 deletions

diff --git a/lib/libpthread/include/pthread.h b/lib/libpthread/include/pthread.h
index ca837eb11f1..e572fae8f73 100644
--- a/lib/libpthread/include/pthread.h
+++ b/lib/libpthread/include/pthread.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pthread.h,v 1.28 2008/06/25 14:58:54 millert Exp $	*/
+/*	$OpenBSD: pthread.h,v 1.29 2008/12/18 09:30:32 guenther Exp $	*/
 
 /*
  * Copyright (c) 1993, 1994 by Chris Provenzano, proven@mit.edu
@@ -203,11 +203,13 @@ int		pthread_attr_getstack(const pthread_attr_t *,
 			void **, size_t *);
 int		pthread_attr_getstacksize(const pthread_attr_t *, size_t *);
 int		pthread_attr_getstackaddr(const pthread_attr_t *, void **);
+int		pthread_attr_getguardsize(const pthread_attr_t *, size_t *);
 int		pthread_attr_getdetachstate(const pthread_attr_t *, int *);
 int		pthread_attr_init(pthread_attr_t *);
 int		pthread_attr_setstacksize(pthread_attr_t *, size_t);
 int		pthread_attr_setstack(pthread_attr_t *, void *, size_t);
 int		pthread_attr_setstackaddr(pthread_attr_t *, void *);
+int		pthread_attr_setguardsize(pthread_attr_t *, size_t);
 int		pthread_attr_setdetachstate(pthread_attr_t *, int);
 void		pthread_cleanup_pop(int);
 void		pthread_cleanup_push(void (*) (void *), void *routine_arg);
diff --git a/lib/libpthread/man/Makefile.inc b/lib/libpthread/man/Makefile.inc
index bfa2dbda449..327457260ac 100644
--- a/lib/libpthread/man/Makefile.inc
+++ b/lib/libpthread/man/Makefile.inc
@@ -1,4 +1,4 @@
-# $OpenBSD: Makefile.inc,v 1.22 2008/07/05 08:03:57 guenther Exp $
+# $OpenBSD: Makefile.inc,v 1.23 2008/12/18 09:30:32 guenther Exp $
 # $FreeBSD: Makefile.inc,v 1.6 1999/08/28 00:03:02 peter Exp $
 
 # POSIX thread man files
@@ -11,6 +11,7 @@ MAN+=	\
 	pthread_attr_setstack.3 \
 	pthread_attr_setstackaddr.3 \
 	pthread_attr_setstacksize.3 \
+	pthread_attr_setguardsize.3 \
 	pthread_attr_setdetachstate.3 \
 	pthread_cleanup_pop.3 \
 	pthread_cleanup_push.3 \
@@ -85,6 +86,7 @@ MLINKS+=flockfile.3 funlockfile.3 \
 	pthread_attr_setstack.3 pthread_attr_getstack.3 \
 	pthread_attr_setstackaddr.3 pthread_attr_getstackaddr.3 \
 	pthread_attr_setstacksize.3 pthread_attr_getstacksize.3 \
+	pthread_attr_setguardsize.3 pthread_attr_getguardsize.3 \
 	pthread_attr_setdetachstate.3 pthread_attr_getdetachstate.3 \
 	pthread_mutexattr.3 pthread_mutexattr_init.3 \
 	pthread_mutexattr.3 pthread_mutexattr_destroy.3 \
diff --git a/lib/libpthread/man/pthread_attr_init.3 b/lib/libpthread/man/pthread_attr_init.3
index 10351aabf1f..7dff56d4b1e 100644
--- a/lib/libpthread/man/pthread_attr_init.3
+++ b/lib/libpthread/man/pthread_attr_init.3
@@ -1,9 +1,9 @@
-.\" $OpenBSD: pthread_attr_init.3,v 1.9 2008/07/05 10:43:07 jmc Exp $
+.\" $OpenBSD: pthread_attr_init.3,v 1.10 2008/12/18 09:30:32 guenther Exp $
 .\" Manual page derived from TOG's UNIX98 documentation.
 .\"
 .\"  David Leonard, 2000. Public Domain.
 .\"
-.Dd $Mdocdate: July 5 2008 $
+.Dd $Mdocdate: December 18 2008 $
 .Dt PTHREAD_ATTR_INIT 3
 .Os
 .Sh NAME
@@ -65,6 +65,7 @@ These functions will not return an error code of
 .Bq Er EINTR .
 .Sh SEE ALSO
 .Xr pthread_attr_setdetachstate 3 ,
+.Xr pthread_attr_setguardsize 3 ,
 .Xr pthread_attr_setstack 3 ,
 .Xr pthread_attr_setstackaddr 3 ,
 .Xr pthread_attr_setstacksize 3 ,
diff --git a/lib/libpthread/man/pthread_attr_setdetachstate.3 b/lib/libpthread/man/pthread_attr_setdetachstate.3
index 6fe3a88229d..fa27a96e7c5 100644
--- a/lib/libpthread/man/pthread_attr_setdetachstate.3
+++ b/lib/libpthread/man/pthread_attr_setdetachstate.3
@@ -1,9 +1,9 @@
-.\" $OpenBSD: pthread_attr_setdetachstate.3,v 1.8 2008/07/05 08:03:57 guenther Exp $
+.\" $OpenBSD: pthread_attr_setdetachstate.3,v 1.9 2008/12/18 09:30:32 guenther Exp $
 .\" Manual page derived from TOG's UNIX98 documentation.
 .\"
 .\"  David Leonard, 2000. Public Domain.
 .\"
-.Dd $Mdocdate: July 5 2008 $
+.Dd $Mdocdate: December 18 2008 $
 .Dt PTHREAD_ATTR_SETDETACHSTATE 3
 .Os
 .Sh NAME
@@ -90,6 +90,7 @@ These functions will not return an error code of
 .Bq Er EINTR .
 .Sh SEE ALSO
 .Xr pthread_attr_init 3 ,
+.Xr pthread_attr_setguardsize 3 ,
 .Xr pthread_attr_setstack 3 ,
 .Xr pthread_attr_setstackaddr 3 ,
 .Xr pthread_attr_setstacksize 3 ,
diff --git a/lib/libpthread/man/pthread_attr_setguardsize.3 b/lib/libpthread/man/pthread_attr_setguardsize.3
new file mode 100644
index 00000000000..471def58d61
--- /dev/null
+++ b/lib/libpthread/man/pthread_attr_setguardsize.3
@@ -0,0 +1,89 @@
+.\" $OpenBSD: pthread_attr_setguardsize.3,v 1.1 2008/12/18 09:30:32 guenther Exp $
+.\" Manual page derived from TOG's XPG6 documentation.
+.\"
+.\"  David Leonard, 2000. Public Domain.
+.\"
+.Dd $Mdocdate: December 18 2008 $
+.Dt PTHREAD_ATTR_SETGUARDSIZE 3
+.Os
+.Sh NAME
+.Nm pthread_attr_setguardsize ,
+.Nm pthread_attr_getguardsize
+.Nd set and get guardsize attribute
+.Sh SYNOPSIS
+.Fd #include <pthread.h>
+.Ft int
+.Fn pthread_attr_setguardsize "pthread_attr_t *attr" "size_t guardsize"
+.Ft int
+.Fn pthread_attr_getguardsize "const pthread_attr_t *attr" "size_t *guardsize"
+.Sh DESCRIPTION
+The functions
+.Fn pthread_attr_setguardsize
+and
+.Fn pthread_attr_getguardsize ,
+respectively, set and get the thread
+creation
+.Va guardsize
+attribute in the
+.Fa attr
+object.
+If
+.Va guardsize
+is zero,
+a guard area shall not be provided for threads created with
+.Fa attr .
+If
+.Va guardsize
+is greater than zero,
+a guard area of at least size
+.Va guardsize
+bytes shall be provided for each thread created with
+.Fa attr .
+.Pp
+The
+.Va guardsize
+attribute controls the size of the guard area for the created
+thread's stack.
+The
+.Va guardsize
+attribute provides protection against overflow of the stack pointer.
+If a thread's stack is created with guard protection,
+the implementation allocates extra memory at the overflow end of
+the stack as a buffer against stack overflow of the stack pointer.
+If an application overflows into this buffer an error shall result
+(possibly in a SIGSEGV signal being delivered to the thread).
+.Sh RETURN VALUES
+Upon successful completion,
+.Fn pthread_attr_setguardsize
+and
+.Fn pthread_attr_getguardsize
+return a value of 0.
+Otherwise, an error number is returned to indicate the error.
+.Pp
+The
+.Fn pthread_attr_getguardsize
+function stores the
+.Va guardsize
+attribute value in
+.Fa guardsize
+if successful.
+.Sh ERRORS
+No errors are defined.
+.Pp
+These functions will not return an error code of
+.Bq Er EINTR .
+.Sh SEE ALSO
+.Xr pthread_attr_init 3 ,
+.Xr pthread_attr_setdetachstate 3 ,
+.Xr pthread_attr_setstack 3 ,
+.Xr pthread_attr_setstackaddr 3 ,
+.Xr pthread_attr_setstacksize 3 ,
+.Xr pthread_create 3 ,
+.Xr pthreads 3
+.Sh STANDARDS
+.Fn pthread_attr_setguardsize
+and
+.Fn pthread_attr_getguardsize
+conform to ISO/IEC 9945-1 ANSI/IEEE
+.Pq Dq Tn POSIX
+Std 1003.1, 2004 Edition.
diff --git a/lib/libpthread/man/pthread_attr_setstack.3 b/lib/libpthread/man/pthread_attr_setstack.3
index c2cd372c8e7..ed4250eedbe 100644
--- a/lib/libpthread/man/pthread_attr_setstack.3
+++ b/lib/libpthread/man/pthread_attr_setstack.3
@@ -1,9 +1,9 @@
-.\" $OpenBSD: pthread_attr_setstack.3,v 1.2 2008/07/05 10:43:07 jmc Exp $
+.\" $OpenBSD: pthread_attr_setstack.3,v 1.3 2008/12/18 09:30:32 guenther Exp $
 .\" Manual page derived from TOG's UNIX98 documentation.
 .\"
 .\"  David Leonard, 2000. Public Domain.
 .\"
-.Dd $Mdocdate: July 5 2008 $
+.Dd $Mdocdate: December 18 2008 $
 .Dt PTHREAD_ATTR_SETSTACK 3
 .Os
 .Sh NAME
@@ -79,6 +79,7 @@ These functions will not return an error code of
 .Sh SEE ALSO
 .Xr pthread_attr_init 3 ,
 .Xr pthread_attr_setdetachstate 3 ,
+.Xr pthread_attr_setguardsize 3 ,
 .Xr pthread_attr_setstackaddr 3 ,
 .Xr pthread_attr_setstacksize 3 ,
 .Xr pthread_create 3 ,
diff --git a/lib/libpthread/man/pthread_attr_setstackaddr.3 b/lib/libpthread/man/pthread_attr_setstackaddr.3
index efb3eea54b4..0de282cd15b 100644
--- a/lib/libpthread/man/pthread_attr_setstackaddr.3
+++ b/lib/libpthread/man/pthread_attr_setstackaddr.3
@@ -1,9 +1,9 @@
-.\" $OpenBSD: pthread_attr_setstackaddr.3,v 1.9 2008/07/05 08:03:57 guenther Exp $
+.\" $OpenBSD: pthread_attr_setstackaddr.3,v 1.10 2008/12/18 09:30:32 guenther Exp $
 .\" Manual page derived from TOG's UNIX98 documentation.
 .\"
 .\"  David Leonard, 2000. Public Domain.
 .\"
-.Dd $Mdocdate: July 5 2008 $
+.Dd $Mdocdate: December 18 2008 $
 .Dt PTHREAD_ATTR_SETSTACKADDR 3
 .Os
 .Sh NAME
@@ -57,6 +57,7 @@ These functions will not return an error code of
 .Sh SEE ALSO
 .Xr pthread_attr_init 3 ,
 .Xr pthread_attr_setdetachstate 3 ,
+.Xr pthread_attr_setguardsize 3 ,
 .Xr pthread_attr_setstack 3 ,
 .Xr pthread_attr_setstacksize 3 ,
 .Xr pthread_create 3 ,
diff --git a/lib/libpthread/man/pthread_attr_setstacksize.3 b/lib/libpthread/man/pthread_attr_setstacksize.3
index b26f31be486..2189e0b1eb1 100644
--- a/lib/libpthread/man/pthread_attr_setstacksize.3
+++ b/lib/libpthread/man/pthread_attr_setstacksize.3
@@ -1,9 +1,9 @@
-.\" $OpenBSD: pthread_attr_setstacksize.3,v 1.8 2008/07/05 08:03:57 guenther Exp $
+.\" $OpenBSD: pthread_attr_setstacksize.3,v 1.9 2008/12/18 09:30:32 guenther Exp $
 .\" Manual page derived from TOG's UNIX98 documentation.
 .\"
 .\"  David Leonard, 2000. Public Domain.
 .\"
-.Dd $Mdocdate: July 5 2008 $
+.Dd $Mdocdate: December 18 2008 $
 .Dt PTHREAD_ATTR_SETSTACKSIZE 3
 .Os
 .Sh NAME
@@ -65,6 +65,7 @@ These functions will not return an error code of
 .Sh SEE ALSO
 .Xr pthread_attr_init 3 ,
 .Xr pthread_attr_setdetachstate 3 ,
+.Xr pthread_attr_setguardsize 3 ,
 .Xr pthread_attr_setstack 3 ,
 .Xr pthread_attr_setstackaddr 3 ,
 .Xr pthread_create 3 ,
diff --git a/lib/libpthread/man/pthread_create.3 b/lib/libpthread/man/pthread_create.3
index 87833f5c736..8e9be64e3c6 100644
--- a/lib/libpthread/man/pthread_create.3
+++ b/lib/libpthread/man/pthread_create.3
@@ -1,4 +1,4 @@
-.\" $OpenBSD: pthread_create.3,v 1.12 2008/07/05 10:43:07 jmc Exp $
+.\" $OpenBSD: pthread_create.3,v 1.13 2008/12/18 09:30:32 guenther Exp $
 .\"
 .\" Copyright (c) 1996 John Birrell <jb@cimlogic.com.au>.
 .\" All rights reserved.
@@ -32,7 +32,7 @@
 .\"
 .\" $FreeBSD: pthread_create.3,v 1.8 1999/08/28 00:03:04 peter Exp $
 .\"
-.Dd $Mdocdate: July 5 2008 $
+.Dd $Mdocdate: December 18 2008 $
 .Dt PTHREAD_CREATE 3
 .Os
 .Sh NAME
@@ -111,6 +111,7 @@ is invalid.
 .Xr fork 2 ,
 .Xr pthread_attr_init 3 ,
 .Xr pthread_attr_setdetachstate 3 ,
+.Xr pthread_attr_setguardsize 3 ,
 .Xr pthread_attr_setstack 3 ,
 .Xr pthread_attr_setstackaddr 3 ,
 .Xr pthread_attr_setstacksize 3 ,
diff --git a/lib/libpthread/man/pthreads.3 b/lib/libpthread/man/pthreads.3
index d760eaaa835..462959cb381 100644
--- a/lib/libpthread/man/pthreads.3
+++ b/lib/libpthread/man/pthreads.3
@@ -1,6 +1,6 @@
-.\" $OpenBSD: pthreads.3,v 1.28 2008/07/05 08:03:57 guenther Exp $
+.\" $OpenBSD: pthreads.3,v 1.29 2008/12/18 09:30:32 guenther Exp $
 .\" David Leonard <d@openbsd.org>, 1998. Public domain.
-.Dd $Mdocdate: July 5 2008 $
+.Dd $Mdocdate: December 18 2008 $
 .Dt PTHREADS 3
 .Os
 .Sh NAME
@@ -84,6 +84,10 @@ Set stackaddr attribute.
 Get stacksize attribute.
 .It Fn pthread_attr_setstacksize
 Set stacksize attribute.
+.It Fn pthread_attr_getguardsize
+Get guardsize attribute.
+.It Fn pthread_attr_setguardsize
+Set guardsize attribute.
 .El
 .Ss Cleanup Routines
 The functions available are as follows:
@@ -491,6 +495,7 @@ environment variable.
 .Xr pthread_atfork 3 ,
 .Xr pthread_attr_init 3 ,
 .Xr pthread_attr_setdetachstate 3 ,
+.Xr pthread_attr_setguardsize 3 ,
 .Xr pthread_attr_setstack 3 ,
 .Xr pthread_attr_setstackaddr 3 ,
 .Xr pthread_attr_setstacksize 3 ,
diff --git a/lib/libpthread/shlib_version b/lib/libpthread/shlib_version
index f461c533903..ba5b9bf5d82 100644
--- a/lib/libpthread/shlib_version
+++ b/lib/libpthread/shlib_version
@@ -1,2 +1,2 @@
 major=11
-minor=0
+minor=1
diff --git a/lib/libpthread/uthread/Makefile.inc b/lib/libpthread/uthread/Makefile.inc
index 3e814dd0500..23d7f229128 100644
--- a/lib/libpthread/uthread/Makefile.inc
+++ b/lib/libpthread/uthread/Makefile.inc
@@ -1,4 +1,4 @@
-# $OpenBSD: Makefile.inc,v 1.20 2007/06/05 18:11:48 kurt Exp $
+# $OpenBSD: Makefile.inc,v 1.21 2008/12/18 09:30:32 guenther Exp $
 # $FreeBSD: Makefile.inc,v 1.19 1999/08/28 00:03:19 peter Exp $
 
 # uthread sources
@@ -12,6 +12,7 @@ SRCS+= \
 	uthread_attr_destroy.c \
 	uthread_attr_init.c \
 	uthread_attr_getdetachstate.c \
+	uthread_attr_getguardsize.c \
 	uthread_attr_getinheritsched.c \
 	uthread_attr_getschedparam.c \
 	uthread_attr_getschedpolicy.c \
@@ -21,6 +22,7 @@ SRCS+= \
 	uthread_attr_getstacksize.c \
 	uthread_attr_setcreatesuspend_np.c \
 	uthread_attr_setdetachstate.c \
+	uthread_attr_setguardsize.c \
 	uthread_attr_setinheritsched.c \
 	uthread_attr_setschedparam.c \
 	uthread_attr_setschedpolicy.c \
diff --git a/lib/libpthread/uthread/pthread_private.h b/lib/libpthread/uthread/pthread_private.h
index bcd64def492..5ed8fab9c08 100644
--- a/lib/libpthread/uthread/pthread_private.h
+++ b/lib/libpthread/uthread/pthread_private.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pthread_private.h,v 1.69 2007/11/20 19:35:36 deraadt Exp $	*/
+/*	$OpenBSD: pthread_private.h,v 1.70 2008/12/18 09:30:32 guenther Exp $	*/
 /*
  * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>.
  * All rights reserved.
@@ -581,6 +581,7 @@ struct stack {
 	SLIST_ENTRY(stack)	qe; /* Queue entry for this stack. */
 	void 			*base;		/* Bottom of useful stack */
 	size_t			size;		/* Size of useful stack */
+	size_t			guardsize;	/* Size of red zone */
 	void			*redzone;	/* Red zone location */
 	void 			*storage;	/* allocated storage */
 };
@@ -957,7 +958,7 @@ SCLASS struct pthread_attr pthread_attr_default
 #ifdef GLOBAL_PTHREAD_PRIVATE
 = { SCHED_RR, 0, TIMESLICE_USEC, PTHREAD_DEFAULT_PRIORITY,
 	PTHREAD_CREATE_RUNNING, PTHREAD_CREATE_JOINABLE, NULL, NULL, NULL,
-	PTHREAD_STACK_DEFAULT };
+	PTHREAD_STACK_DEFAULT, 0 /* set in _thread_init() */ };
 #else
 ;
 #endif
@@ -1184,7 +1185,7 @@ void	_thread_leave_cancellation_point(void);
 void	_thread_cancellation_point(void);
 int	_thread_slow_atomic_lock(volatile _spinlock_lock_t *);
 int	_thread_slow_atomic_is_locked(volatile _spinlock_lock_t *);
-struct stack * _thread_stack_alloc(void *, size_t);
+struct stack * _thread_stack_alloc(void *, size_t, size_t);
 void	_thread_stack_free(struct stack *);
 
 
diff --git a/lib/libpthread/uthread/uthread_attr_getguardsize.c b/lib/libpthread/uthread/uthread_attr_getguardsize.c
new file mode 100644
index 00000000000..b956ed6ecc2
--- /dev/null
+++ b/lib/libpthread/uthread/uthread_attr_getguardsize.c
@@ -0,0 +1,55 @@
+/*	$OpenBSD: uthread_attr_getguardsize.c,v 1.1 2008/12/18 09:30:32 guenther Exp $	*/
+/*
+ * Copyright (c) 1997 John Birrell <jb@cimlogic.com.au>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by John Birrell.
+ * 4. Neither the name of the author nor the names of any co-contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD: uthread_attr_getstacksize.c,v 1.3 1999/08/28 00:03:22 peter Exp $
+ */
+#include <errno.h>
+#ifdef _THREAD_SAFE
+#include <pthread.h>
+#include "pthread_private.h"
+
+int
+pthread_attr_getguardsize(const pthread_attr_t *attr, size_t *guardsize)
+{
+	int	ret;
+
+	/* Check for invalid arguments: */
+	if (attr == NULL || *attr == NULL || guardsize  == NULL)
+		ret = EINVAL;
+	else {
+		/* Return the guard size: */
+		*guardsize = (*attr)->guardsize_attr;
+		ret = 0;
+	}
+	return(ret);
+}
+#endif
diff --git a/lib/libpthread/uthread/uthread_attr_setguardsize.c b/lib/libpthread/uthread/uthread_attr_setguardsize.c
new file mode 100644
index 00000000000..db9acad2fd7
--- /dev/null
+++ b/lib/libpthread/uthread/uthread_attr_setguardsize.c
@@ -0,0 +1,55 @@
+/*	$OpenBSD: uthread_attr_setguardsize.c,v 1.1 2008/12/18 09:30:32 guenther Exp $	*/
+/*
+ * Copyright (c) 1996 John Birrell <jb@cimlogic.com.au>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by John Birrell.
+ * 4. Neither the name of the author nor the names of any co-contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD: uthread_attr_setstacksize.c,v 1.4 1999/08/28 00:03:26 peter Exp $
+ */
+#include <errno.h>
+#ifdef _THREAD_SAFE
+#include <pthread.h>
+#include "pthread_private.h"
+
+int
+pthread_attr_setguardsize(pthread_attr_t *attr, size_t guardsize)
+{
+	int	ret;
+
+	/* Check for invalid arguments: */
+	if (attr == NULL || *attr == NULL)
+		ret = EINVAL;
+	else {
+		/* Save the guard size: */
+		(*attr)->guardsize_attr = guardsize;
+		ret = 0;
+	}
+	return(ret);
+}
+#endif
diff --git a/lib/libpthread/uthread/uthread_create.c b/lib/libpthread/uthread/uthread_create.c
index 3a5f7a626e4..6b5633f9f06 100644
--- a/lib/libpthread/uthread/uthread_create.c
+++ b/lib/libpthread/uthread/uthread_create.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uthread_create.c,v 1.22 2008/07/07 04:59:22 guenther Exp $	*/
+/*	$OpenBSD: uthread_create.c,v 1.23 2008/12/18 09:30:32 guenther Exp $	*/
 /*
  * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
  * All rights reserved.
@@ -87,7 +87,7 @@ pthread_create(pthread_t *thread, const pthread_attr_t *attr,
 
 		/* Allocate a stack: */
 		stack = _thread_stack_alloc(pattr->stackaddr_attr,
-		    pattr->stacksize_attr);
+		    pattr->stacksize_attr, pattr->guardsize_attr);
 		if (stack == NULL) {
 			ret = EAGAIN;
 			free(new_thread);
diff --git a/lib/libpthread/uthread/uthread_init.c b/lib/libpthread/uthread/uthread_init.c
index 19421a04d55..c9b20880ad4 100644
--- a/lib/libpthread/uthread/uthread_init.c
+++ b/lib/libpthread/uthread/uthread_init.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uthread_init.c,v 1.42 2008/06/14 15:40:16 fgsch Exp $	*/
+/*	$OpenBSD: uthread_init.c,v 1.43 2008/12/18 09:30:32 guenther Exp $	*/
 /*
  * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
  * All rights reserved.
@@ -358,6 +358,9 @@ _thread_init(void)
 	_thread_max_fdtsize = (int)rl.rlim_max;
 	_thread_max_pfdtsize = (nfds_t)rl.rlim_max;
 
+	/* Get the default guardsize */
+	pthread_attr_default.guardsize_attr = (size_t)sysconf(_SC_PAGESIZE);
+
 	/* Allocate memory for the file descriptor table: */
 	_thread_fd_table = calloc((size_t)_thread_max_fdtsize,
 				  sizeof(struct fd_table_entry *));
diff --git a/lib/libpthread/uthread/uthread_stack.c b/lib/libpthread/uthread/uthread_stack.c
index bf3e3976444..2212a0a87d2 100644
--- a/lib/libpthread/uthread/uthread_stack.c
+++ b/lib/libpthread/uthread/uthread_stack.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uthread_stack.c,v 1.10 2007/05/18 19:28:50 kurt Exp $	*/
+/*	$OpenBSD: uthread_stack.c,v 1.11 2008/12/18 09:30:32 guenther Exp $	*/
 /*
  * Copyright 1999, David Leonard. All rights reserved.
  * <insert BSD-style license&disclaimer>
@@ -25,15 +25,14 @@
 #include "pthread_private.h"
 
 struct stack *
-_thread_stack_alloc(base, size)
-	void *base;
-	size_t size;
+_thread_stack_alloc(void *base, size_t size, size_t guardsize)
 {
 	struct stack *stack;
 	size_t nbpg = (size_t)getpagesize();
 
 	/* Maintain a stack of default-sized stacks that we can re-use. */
-	if (base == NULL && size == PTHREAD_STACK_DEFAULT) {
+	if (base == NULL && size == PTHREAD_STACK_DEFAULT
+	  && guardsize == pthread_attr_default.guardsize_attr) {
 		if (pthread_mutex_lock(&_gc_mutex) != 0)
 			PANIC("Cannot lock gc mutex");
 
@@ -56,16 +55,24 @@ _thread_stack_alloc(base, size)
 		/* Use the user's storage */
 		stack->base = base;
 		stack->size = size;
+		stack->guardsize = 0;
 		stack->redzone = NULL;
 		stack->storage = NULL;
 		return stack;
 	}
 
-	/* Round size up to closest page boundry */
+	/* Round sizes up to closest page boundry */
 	size = ((size + (nbpg - 1)) / nbpg) * nbpg;
+	guardsize = ((guardsize + (nbpg - 1)) / nbpg) * nbpg;
 
-	/* mmap storage for the stack, with one extra page for redzone */
-	stack->storage = mmap(NULL, size + nbpg, PROT_READ|PROT_WRITE,
+	/* overflow? */
+	if (SIZE_MAX - size < guardsize) {
+		free(stack);
+		return NULL;
+	}
+
+	/* mmap storage for the stack, possibly with page(s) for redzone */
+	stack->storage = mmap(NULL, size + guardsize, PROT_READ|PROT_WRITE,
 	    MAP_ANON|MAP_PRIVATE, -1, 0);
 	if (stack->storage == MAP_FAILED) {
 		free(stack);
@@ -77,16 +84,20 @@ _thread_stack_alloc(base, size)
 	 */
 #if defined(MACHINE_STACK_GROWS_UP)
 	/* Red zone is the last page of the storage: */
-	stack->redzone = (void *)((caddr_t)stack->storage + (ptrdiff_t)size);
+	stack->redzone = (caddr_t)stack->storage + (ptrdiff_t)size;
 	stack->base = stack->storage;
 	stack->size = size;
+	stack->guardsize = guardsize;
 #else
 	/* Red zone is the first page of the storage: */
 	stack->redzone = stack->storage; 
-	stack->base = (caddr_t)stack->redzone + (ptrdiff_t)nbpg;
+	stack->base = (caddr_t)stack->redzone + (ptrdiff_t)guardsize;
 	stack->size = size;
+	stack->guardsize = guardsize;
 #endif
-	if (mprotect(stack->redzone, nbpg, PROT_NONE) == -1)
+	if (!guardsize)
+		stack->redzone = NULL;
+	else if (mprotect(stack->redzone, guardsize, PROT_NONE) == -1)
 		PANIC("Cannot protect stack red zone");
 
 	return stack;
@@ -96,15 +107,14 @@ void
 _thread_stack_free(stack)
 	struct stack *stack;
 {
-	size_t nbpg = (size_t)getpagesize();
-
 	/* Cache allocated stacks of default size: */
-	if (stack->storage != NULL && stack->size == PTHREAD_STACK_DEFAULT)
+	if (stack->storage != NULL && stack->size == PTHREAD_STACK_DEFAULT
+	  && stack->guardsize == pthread_attr_default.guardsize_attr)
 		SLIST_INSERT_HEAD(&_stackq, stack, qe);
 	else {
 		/* unmap storage: */
 		if (stack->storage)
-			munmap(stack->storage, stack->size + nbpg);
+			munmap(stack->storage, stack->size + stack->guardsize);
 
 		/* Free stack information storage: */
 		free(stack);