give msync a cancellation point

1 files changed, 32 insertions, 0 deletions

diff --git a/lib/libc_r/uthread/uthread_msync.c b/lib/libc_r/uthread/uthread_msync.c
new file mode 100644
index 00000000000..246cdde7226
--- /dev/null
+++ b/lib/libc_r/uthread/uthread_msync.c
@@ -0,0 +1,32 @@
+/*
+ * David Leonard <d@openbsd.org>, 1999. Public Domain.
+ *
+ * $OpenBSD: uthread_msync.c,v 1.1 1999/01/17 23:43:18 d Exp $
+ */
+
+#include <sys/types.h>
+#include <sys/mman.h>
+#ifdef _THREAD_SAFE
+#include <pthread.h>
+#include "pthread_private.h"
+
+int
+msync(addr, len, flags)
+	void *addr;
+	size_t len;
+	int flags;
+{
+	int ret;
+
+	/*
+	 * XXX This is quite pointless unless we know how to get the
+	 * file descriptor associated with the memory, and lock it for
+	 * write. The only real use of this wrapper is to guarantee
+	 * a cancellation point, as per the standard. sigh.
+	 */
+	_thread_enter_cancellation_point();
+	ret = _thread_sys_msync(addr, len, flags);
+	_thread_leave_cancellation_point();
+	return (ret);
+}
+#endif