diff options
Diffstat (limited to 'src/pkg/os/getwd.go')
-rw-r--r-- | src/pkg/os/getwd.go | 119 |
1 files changed, 0 insertions, 119 deletions
diff --git a/src/pkg/os/getwd.go b/src/pkg/os/getwd.go deleted file mode 100644 index a72edeaee..000000000 --- a/src/pkg/os/getwd.go +++ /dev/null @@ -1,119 +0,0 @@ -// 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 ( - "sync" - "syscall" -) - -var getwdCache struct { - sync.Mutex - dir string -} - -// useSyscallwd determines whether to use the return value of -// syscall.Getwd based on its error. -var useSyscallwd = func(error) bool { return true } - -// Getwd returns a rooted path name corresponding to the -// current directory. If the current directory can be -// reached via multiple paths (due to symbolic links), -// Getwd may return any one of them. -func Getwd() (dir string, err error) { - // If the operating system provides a Getwd call, use it. - if syscall.ImplementsGetwd { - s, e := syscall.Getwd() - if useSyscallwd(e) { - return s, NewSyscallError("getwd", e) - } - } - - // Otherwise, we're trying to find our way back to ".". - dot, err := Stat(".") - if err != nil { - return "", err - } - - // Clumsy but widespread kludge: - // if $PWD is set and matches ".", use it. - dir = Getenv("PWD") - if len(dir) > 0 && dir[0] == '/' { - d, err := Stat(dir) - if err == nil && SameFile(dot, d) { - return dir, nil - } - } - - // Apply same kludge but to cached dir instead of $PWD. - getwdCache.Lock() - dir = getwdCache.dir - getwdCache.Unlock() - if len(dir) > 0 { - d, err := Stat(dir) - if err == nil && SameFile(dot, d) { - return dir, nil - } - } - - // Root is a special case because it has no parent - // and ends in a slash. - root, err := Stat("/") - if err != nil { - // Can't stat root - no hope. - return "", err - } - if SameFile(root, dot) { - return "/", nil - } - - // General algorithm: find name in parent - // and then find name of parent. Each iteration - // adds /name to the beginning of dir. - dir = "" - for parent := ".."; ; parent = "../" + parent { - if len(parent) >= 1024 { // Sanity check - return "", syscall.ENAMETOOLONG - } - fd, err := Open(parent) - if err != nil { - return "", err - } - - for { - names, err := fd.Readdirnames(100) - if err != nil { - fd.Close() - return "", err - } - for _, name := range names { - d, _ := Lstat(parent + "/" + name) - if SameFile(d, dot) { - dir = "/" + name + dir - goto Found - } - } - } - - Found: - pd, err := fd.Stat() - if err != nil { - return "", err - } - fd.Close() - if SameFile(pd, root) { - break - } - // Set up for next round. - dot = pd - } - - // Save answer as hint to avoid the expensive path next time. - getwdCache.Lock() - getwdCache.dir = dir - getwdCache.Unlock() - - return dir, nil -} |