]> Cypherpunks repositories - gostls13.git/commitdiff
os: implement sameFile on windows
authorAlex Brainman <alex.brainman@gmail.com>
Mon, 27 Feb 2012 01:29:33 +0000 (12:29 +1100)
committerAlex Brainman <alex.brainman@gmail.com>
Mon, 27 Feb 2012 01:29:33 +0000 (12:29 +1100)
Fixes #2511.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5687072

src/pkg/os/file_windows.go
src/pkg/os/os_test.go
src/pkg/os/stat_windows.go

index 82c7429945551b3098ea019f1bd0a79f350010ef..88fa77bb848e5182d21073ff986c798056b6fe9a 100644 (file)
@@ -52,6 +52,7 @@ func NewFile(fd uintptr, name string) *File {
 type dirInfo struct {
        data     syscall.Win32finddata
        needdata bool
+       path     string
 }
 
 const DevNull = "NUL"
@@ -79,6 +80,11 @@ func openDir(name string) (file *File, err error) {
        if e != nil {
                return nil, &PathError{"open", name, e}
        }
+       d.path = name
+       if !isAbs(d.path) {
+               cwd, _ := Getwd()
+               d.path = cwd + `\` + d.path
+       }
        f := NewFile(uintptr(r), name)
        f.dirinfo = d
        return f, nil
@@ -171,7 +177,13 @@ func (file *File) readdir(n int) (fi []FileInfo, err error) {
                if name == "." || name == ".." { // Useless names
                        continue
                }
-               f := toFileInfo(name, d.FileAttributes, d.FileSizeHigh, d.FileSizeLow, d.CreationTime, d.LastAccessTime, d.LastWriteTime)
+               f := &fileStat{
+                       name:    name,
+                       size:    mkSize(d.FileSizeHigh, d.FileSizeLow),
+                       modTime: mkModTime(d.LastWriteTime),
+                       mode:    mkMode(d.FileAttributes),
+                       sys:     mkSys(file.dirinfo.path+`\`+name, d.LastAccessTime, d.CreationTime),
+               }
                n--
                fi = append(fi, f)
        }
index 21e2f374ca22f2f36db8b255abfec4d917a5b46e..02f75b2a7307f8af208f4f54bd0a8201268c0d66 100644 (file)
@@ -1014,3 +1014,38 @@ func TestNilProcessStateString(t *testing.T) {
                t.Errorf("(*ProcessState)(nil).String() = %q, want %q", s, "<nil>")
        }
 }
+
+func TestSameFile(t *testing.T) {
+       fa, err := Create("a")
+       if err != nil {
+               t.Fatalf("Create(a): %v", err)
+       }
+       defer Remove(fa.Name())
+       fa.Close()
+       fb, err := Create("b")
+       if err != nil {
+               t.Fatalf("Create(b): %v", err)
+       }
+       defer Remove(fb.Name())
+       fb.Close()
+
+       ia1, err := Stat("a")
+       if err != nil {
+               t.Fatalf("Stat(a): %v", err)
+       }
+       ia2, err := Stat("a")
+       if err != nil {
+               t.Fatalf("Stat(a): %v", err)
+       }
+       if !SameFile(ia1, ia2) {
+               t.Errorf("files should be same")
+       }
+
+       ib, err := Stat("b")
+       if err != nil {
+               t.Fatalf("Stat(b): %v", err)
+       }
+       if SameFile(ia1, ib) {
+               t.Errorf("files should be different")
+       }
+}
index ffb679f4170f0b2accf658d6f8423144b5f96895..19e215e935fbd4d24e733a3cb15fb48545a7ecc1 100644 (file)
@@ -5,6 +5,7 @@
 package os
 
 import (
+       "sync"
        "syscall"
        "time"
        "unsafe"
@@ -25,7 +26,13 @@ func (file *File) Stat() (fi FileInfo, err error) {
        if e != nil {
                return nil, &PathError{"GetFileInformationByHandle", file.name, e}
        }
-       return toFileInfo(basename(file.name), d.FileAttributes, d.FileSizeHigh, d.FileSizeLow, d.CreationTime, d.LastAccessTime, d.LastWriteTime), nil
+       return &fileStat{
+               name:    basename(file.name),
+               size:    mkSize(d.FileSizeHigh, d.FileSizeLow),
+               modTime: mkModTime(d.LastWriteTime),
+               mode:    mkMode(d.FileAttributes),
+               sys:     mkSysFromFI(&d),
+       }, nil
 }
 
 // Stat returns a FileInfo structure describing the named file.
@@ -39,7 +46,18 @@ func Stat(name string) (fi FileInfo, err error) {
        if e != nil {
                return nil, &PathError{"GetFileAttributesEx", name, e}
        }
-       return toFileInfo(basename(name), d.FileAttributes, d.FileSizeHigh, d.FileSizeLow, d.CreationTime, d.LastAccessTime, d.LastWriteTime), nil
+       path := name
+       if !isAbs(path) {
+               cwd, _ := Getwd()
+               path = cwd + `\` + path
+       }
+       return &fileStat{
+               name:    basename(name),
+               size:    mkSize(d.FileSizeHigh, d.FileSizeLow),
+               modTime: mkModTime(d.LastWriteTime),
+               mode:    mkMode(d.FileAttributes),
+               sys:     mkSys(path, d.LastAccessTime, d.CreationTime),
+       }, nil
 }
 
 // Lstat returns the FileInfo structure describing the named file.
@@ -75,37 +93,144 @@ func basename(name string) string {
        return name
 }
 
-type winTimes struct {
-       atime, ctime syscall.Filetime
+func isSlash(c uint8) bool {
+       return c == '\\' || c == '/'
+}
+
+func isAbs(path string) (b bool) {
+       v := volumeName(path)
+       if v == "" {
+               return false
+       }
+       path = path[len(v):]
+       if path == "" {
+               return false
+       }
+       return isSlash(path[0])
 }
 
-func toFileInfo(name string, fa, sizehi, sizelo uint32, ctime, atime, mtime syscall.Filetime) FileInfo {
-       fs := &fileStat{
-               name:    name,
-               size:    int64(sizehi)<<32 + int64(sizelo),
-               modTime: time.Unix(0, mtime.Nanoseconds()),
-               sys:     &winTimes{atime, ctime},
+func volumeName(path string) (v string) {
+       if len(path) < 2 {
+               return ""
        }
+       // with drive letter
+       c := path[0]
+       if path[1] == ':' &&
+               ('0' <= c && c <= '9' || 'a' <= c && c <= 'z' ||
+                       'A' <= c && c <= 'Z') {
+               return path[:2]
+       }
+       // is it UNC
+       if l := len(path); l >= 5 && isSlash(path[0]) && isSlash(path[1]) &&
+               !isSlash(path[2]) && path[2] != '.' {
+               // first, leading `\\` and next shouldn't be `\`. its server name.
+               for n := 3; n < l-1; n++ {
+                       // second, next '\' shouldn't be repeated.
+                       if isSlash(path[n]) {
+                               n++
+                               // third, following something characters. its share name.
+                               if !isSlash(path[n]) {
+                                       if path[n] == '.' {
+                                               break
+                                       }
+                                       for ; n < l; n++ {
+                                               if isSlash(path[n]) {
+                                                       break
+                                               }
+                                       }
+                                       return path[:n]
+                               }
+                               break
+                       }
+               }
+       }
+       return ""
+}
+
+type winSys struct {
+       sync.Mutex
+       path              string
+       atime, ctime      syscall.Filetime
+       vol, idxhi, idxlo uint32
+}
+
+func mkSize(hi, lo uint32) int64 {
+       return int64(hi)<<32 + int64(lo)
+}
+
+func mkModTime(mtime syscall.Filetime) time.Time {
+       return time.Unix(0, mtime.Nanoseconds())
+}
+
+func mkMode(fa uint32) (m FileMode) {
        if fa&syscall.FILE_ATTRIBUTE_DIRECTORY != 0 {
-               fs.mode |= ModeDir
+               m |= ModeDir
        }
        if fa&syscall.FILE_ATTRIBUTE_READONLY != 0 {
-               fs.mode |= 0444
+               m |= 0444
        } else {
-               fs.mode |= 0666
+               m |= 0666
        }
-       return fs
+       return m
+}
+
+func mkSys(path string, atime, ctime syscall.Filetime) *winSys {
+       return &winSys{
+               path:  path,
+               atime: atime,
+               ctime: ctime,
+       }
+}
+
+func mkSysFromFI(i *syscall.ByHandleFileInformation) *winSys {
+       return &winSys{
+               atime: i.LastAccessTime,
+               ctime: i.CreationTime,
+               vol:   i.VolumeSerialNumber,
+               idxhi: i.FileIndexHigh,
+               idxlo: i.FileIndexLow,
+       }
+}
+
+func (s *winSys) loadFileId() error {
+       if s.path == "" {
+               // already done
+               return nil
+       }
+       s.Lock()
+       defer s.Unlock()
+       h, e := syscall.CreateFile(syscall.StringToUTF16Ptr(s.path), syscall.GENERIC_READ, syscall.FILE_SHARE_READ, nil, syscall.OPEN_EXISTING, 0, 0)
+       if e != nil {
+               return e
+       }
+       defer syscall.CloseHandle(h)
+       var i syscall.ByHandleFileInformation
+       e = syscall.GetFileInformationByHandle(syscall.Handle(h), &i)
+       if e != nil {
+               return e
+       }
+       s.path = ""
+       s.vol = i.VolumeSerialNumber
+       s.idxhi = i.FileIndexHigh
+       s.idxlo = i.FileIndexLow
+       return nil
 }
 
 func sameFile(sys1, sys2 interface{}) bool {
-       // TODO(rsc): Do better than this, but this matches what
-       // used to happen when code compared .Dev and .Ino,
-       // which were both always zero.  Obviously not all files
-       // are the same.
-       return true
+       s1 := sys1.(*winSys)
+       s2 := sys2.(*winSys)
+       e := s1.loadFileId()
+       if e != nil {
+               panic(e)
+       }
+       e = s2.loadFileId()
+       if e != nil {
+               panic(e)
+       }
+       return s1.vol == s2.vol && s1.idxhi == s2.idxhi && s1.idxlo == s2.idxlo
 }
 
 // For testing.
 func atime(fi FileInfo) time.Time {
-       return time.Unix(0, fi.Sys().(*winTimes).atime.Nanoseconds())
+       return time.Unix(0, fi.Sys().(*winSys).atime.Nanoseconds())
 }