code review 5416060: io: new FileInfo, FileMode types + update tree

src/pkg/os/stat_linux.go

 // 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"
 )
 
-func isSymlink(stat *syscall.Stat_t) bool {
-        return stat.Mode&syscall.S_IFMT == syscall.S_IFLNK
+func sameFile(fs1, fs2 *FileStat) bool {
+        sys1 := fs1.Sys.(*syscall.Stat_t)
+        sys2 := fs2.Sys.(*syscall.Stat_t)
+        return sys1.Dev == sys2.Dev && sys1.Ino == sys2.Ino
 }
 
-func fileInfoFromStat(name string, fi *FileInfo, lstat, stat *syscall.Stat_t) *FileInfo {
-        fi.Dev = stat.Dev
-        fi.Ino = stat.Ino
-        fi.Nlink = uint64(stat.Nlink)
-        fi.Mode = stat.Mode
-        fi.Uid = int(stat.Uid)
-        fi.Gid = int(stat.Gid)
-        fi.Rdev = stat.Rdev
-        fi.Size = stat.Size
-        fi.Blksize = int64(stat.Blksize)
-        fi.Blocks = stat.Blocks
-        fi.AccessTime = timespecToTime(stat.Atim)
-        fi.ModTime = timespecToTime(stat.Mtim)
-        fi.ChangeTime = timespecToTime(stat.Ctim)
-        fi.Name = basename(name)
-        if isSymlink(lstat) && !isSymlink(stat) {
-                fi.FollowedSymlink = true
+func fileInfoFromStat(st *syscall.Stat_t, name string) FileInfo {
+        fs := &FileStat{
+                name:    basename(name),
+                size:    int64(st.Size),
+                modTime: timespecToTime(st.Mtim),
+                Sys:     st,
         }
-        return fi
+        fs.mode = FileMode(st.Mode & 0777)
+        switch st.Mode & syscall.S_IFMT {
+        case syscall.S_IFBLK, syscall.S_IFCHR:
+                fs.mode |= ModeDevice
+        case syscall.S_IFDIR:
+                fs.mode |= ModeDir
+        case syscall.S_IFIFO:
+                fs.mode |= ModeNamedPipe
+        case syscall.S_IFLNK:
+                fs.mode |= ModeSymlink
+        case syscall.S_IFREG:
+                // nothing to do
+        case syscall.S_IFSOCK:
+                fs.mode |= ModeSocket
+        }
+        if st.Mode&syscall.S_ISGID != 0 {
+                fs.mode |= ModeSetgid
+        }
+        if st.Mode&syscall.S_ISUID != 0 {
+                fs.mode |= ModeSetuid
+        }
+        return fs
 }
 
 func timespecToTime(ts syscall.Timespec) time.Time {
         return time.Unix(int64(ts.Sec), int64(ts.Nsec))
 }
+
+// For testing.
+func atime(fi FileInfo) time.Time {
+        return timespecToTime(fi.(*FileStat).Sys.(*syscall.Stat_t).Atim)
+}