add pthread_cancel, obtained from OpenBSD.

eischen (Daniel Eischen) added wrappers to protect against cancled
threads orphaning internal resources.

the cancelability code is still a bit fuzzy but works for test
programs of my own, OpenBSD's and some examples from ORA's books.

add readdir_r to both libc and libc_r

add some 'const' attributes to function parameters

Reviewed by: eischen, jasone

1 files changed, 7 insertions, 4 deletions

diff --git a/lib/libpthread/thread/thr_open.c b/lib/libpthread/thread/thr_open.c
index 2f30ae7..4e9993e 100644
--- a/lib/libpthread/thread/thr_open.c
+++ b/lib/libpthread/thread/thr_open.c
@@ -44,10 +44,11 @@
 int
 open(const char *path, int flags,...)
 {
-	int             fd;
-	int             mode = 0;
-	int             status;
-	va_list         ap;
+	int	fd;
+	int	mode = 0;
+	va_list	ap;
+
+	_thread_enter_cancellation_point();
 
 	/* Check if the file is being created: */
 	if (flags & O_CREAT) {
@@ -68,6 +69,8 @@ open(const char *path, int flags,...)
 		fd = -1;
 	}
 
+	_thread_leave_cancellation_point();
+
 	/* Return the file descriptor or -1 on error: */
 	return (fd);
 }