code review 4149046: os: Plan 9 support.

src/pkg/os/stat_plan9.go

Index: src/pkg/os/stat_plan9.go
===================================================================
new file mode 100644
--- /dev/null
+++ b/src/pkg/os/stat_plan9.go
@@ -0,0 +1,81 @@
+// Copyright 2011 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"
+
+func fileInfoFromStat(fi *FileInfo, d *Dir) *FileInfo {
+	fi.Dev = uint64(d.Qid.Vers) | uint64(d.Qid.Type<<32)
+	fi.Ino = d.Qid.Path
+
+	fi.Mode = uint32(d.Mode) & 0777
+	if (d.Mode & syscall.DMDIR) == syscall.DMDIR {
+		fi.Mode |= syscall.S_IFDIR
+	} else {
+		fi.Mode |= syscall.S_IFREG
+	}
+
+	fi.Size = int64(d.Length)
+	fi.Atime_ns = 1e9 * int64(d.Atime)
+	fi.Mtime_ns = 1e9 * int64(d.Mtime)
+	fi.Name = d.Name
+	fi.FollowedSymlink = false
+	return fi
+}
+
+// arg is an open *File or a path string. 
+func dirstat(arg interface{}) (fi *FileInfo, err Error) {
+	var name string
+	nd := syscall.STATFIXLEN + 16*4
+
+	for i := 0; i < 2; i++ { /* should work by the second try */
+		buf := make([]byte, nd)
+
+		var n int
+		var e syscall.Error
+
+		switch syscall_arg := arg.(type) {
+		case *File:
+			name = syscall_arg.name
+			n, e = syscall.Fstat(syscall_arg.fd, buf)
+		case string:
+			name = syscall_arg
+			n, e = syscall.Stat(name, buf)
+		}
+
+		if e != nil {
+			return nil, &PathError{"stat", name, e}
+		}
+
+		if n < syscall.STATFIXLEN {
+			return nil, &PathError{"stat", name, Eshortstat}
+		}
+
+		ntmp, _ := gbit16(buf)
+		nd = int(ntmp)
+
+		if nd <= n {
+			d, e := UnmarshalDir(buf[:n])
+
+			if e != nil {
+				return nil, &PathError{"stat", name, e}
+			}
+
+			return fileInfoFromStat(new(FileInfo), d), nil
+		}
+	}
+
+	return nil, &PathError{"stat", name, Ebadstat}
+}
+
+
+// Stat returns a FileInfo structure describing the named file and an error, if any.
+func Stat(name string) (fi *FileInfo, err Error) {
+	return dirstat(name)
+}
+
+func Lstat(name string) (fi *FileInfo, err Error) {

[r, 2011/03/31 22:57:46]

copy the comment for Lstat from file.go

[paulzhol, 2011/04/01 20:16:44]

Done.

+	return dirstat(name)
+}