vendor: adding in golang.org/x/sys/unix package

This commit adds in the golang.org/x/sys/unix package. This package
provides a low-level interface to unix syscalls. We will uses this
package instead of the built-in "syscall" package because the syscall
package is locked down (https://golang.org/pkg/syscall) and is not
exposing any new kernel functionality.

In fact, this is actually a patched version of the x/sys/unix package
pending review (first part: https://go-review.googlesource.com/c/37943).
The version included in this commit exposes all of the filesystem
encryption kernel interfaces to Go code.

Change-Id: Ic5f9c98b858ccb00db97502c9a60e9249aa8ba38

1 files changed, 38 insertions, 0 deletions

diff --git a/vendor/golang.org/x/sys/unix/openbsd_pledge.go b/vendor/golang.org/x/sys/unix/openbsd_pledge.go
new file mode 100644
index 0000000..db4f72e
--- /dev/null
+++ b/vendor/golang.org/x/sys/unix/openbsd_pledge.go
@@ -0,0 +1,38 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build openbsd
+// +build 386 amd64 arm
+
+package unix
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+const (
+	SYS_PLEDGE = 108
+)
+
+// Pledge implements the pledge syscall. For more information see pledge(2).
+func Pledge(promises string, paths []string) error {
+	promisesPtr, err := syscall.BytePtrFromString(promises)
+	if err != nil {
+		return err
+	}
+	promisesUnsafe, pathsUnsafe := unsafe.Pointer(promisesPtr), unsafe.Pointer(nil)
+	if paths != nil {
+		var pathsPtr []*byte
+		if pathsPtr, err = syscall.SlicePtrFromStrings(paths); err != nil {
+			return err
+		}
+		pathsUnsafe = unsafe.Pointer(&pathsPtr[0])
+	}
+	_, _, e := syscall.Syscall(SYS_PLEDGE, uintptr(promisesUnsafe), uintptr(pathsUnsafe), 0)
+	if e != 0 {
+		return e
+	}
+	return nil
+}