1 files changed, 107 insertions, 0 deletions
diff --git a/runsc/fsgofer/fsgofer_unsafe.go b/runsc/fsgofer/fsgofer_unsafe.go
new file mode 100644
index 000000000..58af5e44d
--- /dev/null
+++ b/runsc/fsgofer/fsgofer_unsafe.go
@@ -0,0 +1,107 @@
+// Copyright 2018 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package fsgofer
+
+import (
+	"syscall"
+	"unsafe"
+
+	"gvisor.googlesource.com/gvisor/pkg/abi/linux"
+	"gvisor.googlesource.com/gvisor/pkg/syserr"
+)
+
+func statAt(dirFd int, name string) (syscall.Stat_t, error) {
+	nameBytes, err := syscall.BytePtrFromString(name)
+	if err != nil {
+		return syscall.Stat_t{}, err
+	}
+	namePtr := unsafe.Pointer(nameBytes)
+
+	var stat syscall.Stat_t
+	statPtr := unsafe.Pointer(&stat)
+
+	if _, _, errno := syscall.Syscall6(
+		syscall.SYS_NEWFSTATAT,
+		uintptr(dirFd),
+		uintptr(namePtr),
+		uintptr(statPtr),
+		linux.AT_SYMLINK_NOFOLLOW,
+		0,
+		0); errno != 0 {
+
+		return syscall.Stat_t{}, syserr.FromHost(errno).ToError()
+	}
+	return stat, nil
+}
+
+func utimensat(dirFd int, name string, times [2]syscall.Timespec, flags int) error {
+	// utimensat(2) doesn't accept empty name, instead name must be nil to make it
+	// operate directly on 'dirFd' unlike other *at syscalls.
+	var namePtr unsafe.Pointer
+	if name != "" {
+		nameBytes, err := syscall.BytePtrFromString(name)
+		if err != nil {
+			return err
+		}
+		namePtr = unsafe.Pointer(nameBytes)
+	}
+
+	timesPtr := unsafe.Pointer(&times[0])
+
+	if _, _, errno := syscall.Syscall6(
+		syscall.SYS_UTIMENSAT,
+		uintptr(dirFd),
+		uintptr(namePtr),
+		uintptr(timesPtr),
+		uintptr(flags),
+		0,
+		0); errno != 0 {
+
+		return syserr.FromHost(errno).ToError()
+	}
+	return nil
+}
+
+func renameat(oldDirFD int, oldName string, newDirFD int, newName string) error {
+	var oldNamePtr unsafe.Pointer
+	if oldName != "" {
+		nameBytes, err := syscall.BytePtrFromString(oldName)
+		if err != nil {
+			return err
+		}
+		oldNamePtr = unsafe.Pointer(nameBytes)
+	}
+	var newNamePtr unsafe.Pointer
+	if newName != "" {
+		nameBytes, err := syscall.BytePtrFromString(newName)
+		if err != nil {
+			return err
+		}
+		newNamePtr = unsafe.Pointer(nameBytes)
+	}
+
+	if _, _, errno := syscall.Syscall6(
+		syscall.SYS_RENAMEAT,
+		uintptr(oldDirFD),
+		uintptr(oldNamePtr),
+		uintptr(newDirFD),
+		uintptr(newNamePtr),
+		0,
+		0); errno != 0 {
+
+		return syserr.FromHost(errno).ToError()
+	}
+	return nil
+}