path/filepath: make UNC file names work

Fixes #2201

R=golang-dev, r, rsc, alex.brainman, robert.hencke, jp
CC=golang-dev
https://golang.org/cl/4950051

diff --git a/src/pkg/path/filepath/path.go b/src/pkg/path/filepath/path.go
index 3d5b915c1013641049ef592e9fbc5a213397f6eb..97a89d519146e2096f107ac7caa73aa62a341710 100644 (file)
--- a/src/pkg/path/filepath/path.go
+++ b/src/pkg/path/filepath/path.go
@@ -41,9 +41,12 @@ func Clean(path string) string {
        vol := VolumeName(path)
        path = path[len(vol):]
        if path == "" {
+               if len(vol) > 1 && vol[1] != ':' {
+                       // should be UNC
+                       return FromSlash(vol)
+               }
                return vol + "."
        }
-
        rooted := os.IsPathSeparator(path[0])
 
        // Invariants:
@@ -144,8 +147,9 @@ func SplitList(path string) []string {
 // If there is no Separator in path, Split returns an empty dir
 // and file set to path.
 func Split(path string) (dir, file string) {
+       vol := VolumeName(path)
        i := len(path) - 1
-       for i >= 0 && !os.IsPathSeparator(path[i]) {
+       for i >= len(vol) && !os.IsPathSeparator(path[i]) {
                i--
        }
        return path[:i+1], path[i+1:]

diff --git a/src/pkg/path/filepath/path_test.go b/src/pkg/path/filepath/path_test.go
index 395b12775a9ed62c4854e9b4aace65efee29afba..9d28992454d9ea344371cbe8243e0c09cbfba696 100644 (file)
--- a/src/pkg/path/filepath/path_test.go
+++ b/src/pkg/path/filepath/path_test.go
@@ -73,9 +73,17 @@ var wincleantests = []PathTest{
        {`c:\abc`, `c:\abc`},
        {`c:abc\..\..\.\.\..\def`, `c:..\..\def`},
        {`c:\abc\def\..\..`, `c:\`},
+       {`c:\..\abc`, `c:\abc`},
        {`c:..\abc`, `c:..\abc`},
        {`\`, `\`},
        {`/`, `\`},
+       {`\\i\..\c$`, `\c$`},
+       {`\\i\..\i\c$`, `\i\c$`},
+       {`\\i\..\I\c$`, `\I\c$`},
+       {`\\host\share\foo\..\bar`, `\\host\share\bar`},
+       {`//host/share/foo/../baz`, `\\host\share\baz`},
+       {`\\a\b\..\c`, `\\a\b\c`},
+       {`\\a\b`, `\\a\b`},
 }
 
 func TestClean(t *testing.T) {
@@ -146,9 +154,25 @@ var unixsplittests = []SplitTest{
        {"/", "/", ""},
 }
 
+var winsplittests = []SplitTest{
+       {`c:`, `c:`, ``},
+       {`c:/`, `c:/`, ``},
+       {`c:/foo`, `c:/`, `foo`},
+       {`c:/foo/bar`, `c:/foo/`, `bar`},
+       {`//host/share`, `//host/share`, ``},
+       {`//host/share/`, `//host/share/`, ``},
+       {`//host/share/foo`, `//host/share/`, `foo`},
+       {`\\host\share`, `\\host\share`, ``},
+       {`\\host\share\`, `\\host\share\`, ``},
+       {`\\host\share\foo`, `\\host\share\`, `foo`},
+}
+
 func TestSplit(t *testing.T) {
        var splittests []SplitTest
        splittests = unixsplittests
+       if runtime.GOOS == "windows" {
+               splittests = append(splittests, winsplittests...)
+       }
        for _, test := range splittests {
                if d, f := filepath.Split(test.path); d != test.dir || f != test.file {
                        t.Errorf("Split(%q) = %q, %q, want %q, %q", test.path, d, f, test.dir, test.file)
@@ -186,6 +210,8 @@ var winjointests = []JoinTest{
        {[]string{`C:\Windows\`, ``}, `C:\Windows`},
        {[]string{`C:\`, `Windows`}, `C:\Windows`},
        {[]string{`C:`, `Windows`}, `C:\Windows`},
+       {[]string{`\\host\share`, `foo`}, `\\host\share\foo`},
+       {[]string{`//host/share`, `foo/bar`}, `\\host\share\foo\bar`},
 }
 
 // join takes a []string and passes it to Join.
@@ -422,6 +448,8 @@ var winisabstests = []IsAbsTest{
        {`\`, false},
        {`\Windows`, false},
        {`c:a\b`, false},
+       {`\\host\share\foo`, true},
+       {`//host/share/foo/bar`, true},
 }
 
 func TestIsAbs(t *testing.T) {
@@ -574,3 +602,43 @@ func TestAbs(t *testing.T) {
                }
        }
 }
+
+type VolumeNameTest struct {
+       path string
+       vol  string
+}
+
+var volumenametests = []VolumeNameTest{
+       {`c:/foo/bar`, `c:`},
+       {`c:`, `c:`},
+       {``, ``},
+       {`\\\host`, ``},
+       {`\\\host\`, ``},
+       {`\\\host\share`, ``},
+       {`\\\host\\share`, ``},
+       {`\\host`, ``},
+       {`//host`, ``},
+       {`\\host\`, ``},
+       {`//host/`, ``},
+       {`\\host\share`, `\\host\share`},
+       {`//host/share`, `//host/share`},
+       {`\\host\share\`, `\\host\share`},
+       {`//host/share/`, `//host/share`},
+       {`\\host\share\foo`, `\\host\share`},
+       {`//host/share/foo`, `//host/share`},
+       {`\\host\share\\foo\\\bar\\\\baz`, `\\host\share`},
+       {`//host/share//foo///bar////baz`, `//host/share`},
+       {`\\host\share\foo\..\bar`, `\\host\share`},
+       {`//host/share/foo/../bar`, `//host/share`},
+}
+
+func TestVolumeName(t *testing.T) {
+       if runtime.GOOS != "windows" {
+               return
+       }
+       for _, v := range volumenametests {
+               if vol := filepath.VolumeName(v.path); vol != v.vol {
+                       t.Errorf("VolumeName(%q)=%q, want %q", v.path, vol, v.vol)
+               }
+       }
+}

diff --git a/src/pkg/path/filepath/path_windows.go b/src/pkg/path/filepath/path_windows.go
index 2535697fd9eed8c9243020b31a974067d27707e5..9692fd978c5da3b094d12313c3ebda6a214c29bb 100644 (file)
--- a/src/pkg/path/filepath/path_windows.go
+++ b/src/pkg/path/filepath/path_windows.go
@@ -4,7 +4,13 @@
 
 package filepath
 
-import "strings"
+import (
+       "strings"
+)
+
+func isSlash(c uint8) bool {
+       return c == '\\' || c == '/'
+}
 
 // IsAbs returns true if the path is absolute.
 func IsAbs(path string) (b bool) {
@@ -16,11 +22,12 @@ func IsAbs(path string) (b bool) {
        if path == "" {
                return false
        }
-       return path[0] == '/' || path[0] == '\\'
+       return isSlash(path[0])
 }
 
 // VolumeName returns leading volume name.  
 // Given "C:\foo\bar" it returns "C:" under windows.
+// Given "\\host\share\foo" it returns "\\host\share".
 // On other platforms it returns "".
 func VolumeName(path string) (v string) {
        if len(path) < 2 {
@@ -33,6 +40,30 @@ func VolumeName(path string) (v string) {
                        '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 ""
 }