Darwin support for Finder

Bug: 62455338

Test: m -j # while on Mac

Change-Id: Ib63e8e10bddcb3b507878364218273e8a5a8aa82

fs/fs_darwin.go

@@ -0,0 +1,49 @@
+// Copyright 2017 Google Inc. All rights reserved.
+//
+// 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 fs
+
+import (
+	"fmt"
+	"os"
+	"syscall"
+	"time"
+)
+
+func (osFs) InodeNumber(info os.FileInfo) (number uint64, err error) {
+	sys := info.Sys()
+	darwinStats, ok := sys.(*syscall.Stat_t)
+	if ok {
+		return darwinStats.Ino, nil
+	}
+	return 0, fmt.Errorf("%v is not a *syscall.Stat_t", sys)
+}
+
+func (osFs) DeviceNumber(info os.FileInfo) (number uint64, err error) {
+	sys := info.Sys()
+	darwinStats, ok := sys.(*syscall.Stat_t)
+	if ok {
+		return uint64(darwinStats.Dev), nil
+	}
+	return 0, fmt.Errorf("%v is not a *syscall.Stat_t", sys)
+}
+
+func (osFs) PermTime(info os.FileInfo) (when time.Time, err error) {
+	sys := info.Sys()
+	darwinStats, ok := sys.(*syscall.Stat_t)
+	if ok {
+		return time.Unix(darwinStats.Ctimespec.Sec, darwinStats.Ctimespec.Nsec), nil
+	}
+	return time.Time{}, fmt.Errorf("%v is not a *syscall.Stat_t", sys)
+}