1 files changed, 118 insertions, 0 deletions
diff --git a/src/os/types.go b/src/os/types.go
new file mode 100644
index 000000000..473d431d4
--- /dev/null
+++ b/src/os/types.go
@@ -0,0 +1,118 @@
+// Copyright 2009 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.
+
+package os
+
+import (
+	"syscall"
+	"time"
+)
+
+// Getpagesize returns the underlying system's memory page size.
+func Getpagesize() int { return syscall.Getpagesize() }
+
+// A FileInfo describes a file and is returned by Stat and Lstat.
+type FileInfo interface {
+	Name() string       // base name of the file
+	Size() int64        // length in bytes for regular files; system-dependent for others
+	Mode() FileMode     // file mode bits
+	ModTime() time.Time // modification time
+	IsDir() bool        // abbreviation for Mode().IsDir()
+	Sys() interface{}   // underlying data source (can return nil)
+}
+
+// A FileMode represents a file's mode and permission bits.
+// The bits have the same definition on all systems, so that
+// information about files can be moved from one system
+// to another portably.  Not all bits apply to all systems.
+// The only required bit is ModeDir for directories.
+type FileMode uint32
+
+// The defined file mode bits are the most significant bits of the FileMode.
+// The nine least-significant bits are the standard Unix rwxrwxrwx permissions.
+// The values of these bits should be considered part of the public API and
+// may be used in wire protocols or disk representations: they must not be
+// changed, although new bits might be added.
+const (
+	// The single letters are the abbreviations
+	// used by the String method's formatting.
+	ModeDir        FileMode = 1 << (32 - 1 - iota) // d: is a directory
+	ModeAppend                                     // a: append-only
+	ModeExclusive                                  // l: exclusive use
+	ModeTemporary                                  // T: temporary file (not backed up)
+	ModeSymlink                                    // L: symbolic link
+	ModeDevice                                     // D: device file
+	ModeNamedPipe                                  // p: named pipe (FIFO)
+	ModeSocket                                     // S: Unix domain socket
+	ModeSetuid                                     // u: setuid
+	ModeSetgid                                     // g: setgid
+	ModeCharDevice                                 // c: Unix character device, when ModeDevice is set
+	ModeSticky                                     // t: sticky
+
+	// Mask for the type bits. For regular files, none will be set.
+	ModeType = ModeDir | ModeSymlink | ModeNamedPipe | ModeSocket | ModeDevice
+
+	ModePerm FileMode = 0777 // permission bits
+)
+
+func (m FileMode) String() string {
+	const str = "dalTLDpSugct"
+	var buf [32]byte // Mode is uint32.
+	w := 0
+	for i, c := range str {
+		if m&(1<<uint(32-1-i)) != 0 {
+			buf[w] = byte(c)
+			w++
+		}
+	}
+	if w == 0 {
+		buf[w] = '-'
+		w++
+	}
+	const rwx = "rwxrwxrwx"
+	for i, c := range rwx {
+		if m&(1<<uint(9-1-i)) != 0 {
+			buf[w] = byte(c)
+		} else {
+			buf[w] = '-'
+		}
+		w++
+	}
+	return string(buf[:w])
+}
+
+// IsDir reports whether m describes a directory.
+// That is, it tests for the ModeDir bit being set in m.
+func (m FileMode) IsDir() bool {
+	return m&ModeDir != 0
+}
+
+// IsRegular reports whether m describes a regular file.
+// That is, it tests that no mode type bits are set.
+func (m FileMode) IsRegular() bool {
+	return m&ModeType == 0
+}
+
+// Perm returns the Unix permission bits in m.
+func (m FileMode) Perm() FileMode {
+	return m & ModePerm
+}
+
+func (fs *fileStat) Name() string { return fs.name }
+func (fs *fileStat) IsDir() bool  { return fs.Mode().IsDir() }
+
+// SameFile reports whether fi1 and fi2 describe the same file.
+// For example, on Unix this means that the device and inode fields
+// of the two underlying structures are identical; on other systems
+// the decision may be based on the path names.
+// SameFile only applies to results returned by this package's Stat.
+// It returns false in other cases.
+func SameFile(fi1, fi2 FileInfo) bool {
+	fs1, ok1 := fi1.(*fileStat)
+	fs2, ok2 := fi2.(*fileStat)
+	if !ok1 || !ok2 {
+		return false
+	}
+	return sameFile(fs1, fs2)
+}