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-rw-r--r--src/pkg/path/path.go218
1 files changed, 0 insertions, 218 deletions
diff --git a/src/pkg/path/path.go b/src/pkg/path/path.go
deleted file mode 100644
index bdb85c6b9..000000000
--- a/src/pkg/path/path.go
+++ /dev/null
@@ -1,218 +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 path implements utility routines for manipulating slash-separated
-// paths.
-package path
-
-import (
- "strings"
-)
-
-// A lazybuf is a lazily constructed path buffer.
-// It supports append, reading previously appended bytes,
-// and retrieving the final string. It does not allocate a buffer
-// to hold the output until that output diverges from s.
-type lazybuf struct {
- s string
- buf []byte
- w int
-}
-
-func (b *lazybuf) index(i int) byte {
- if b.buf != nil {
- return b.buf[i]
- }
- return b.s[i]
-}
-
-func (b *lazybuf) append(c byte) {
- if b.buf == nil {
- if b.w < len(b.s) && b.s[b.w] == c {
- b.w++
- return
- }
- b.buf = make([]byte, len(b.s))
- copy(b.buf, b.s[:b.w])
- }
- b.buf[b.w] = c
- b.w++
-}
-
-func (b *lazybuf) string() string {
- if b.buf == nil {
- return b.s[:b.w]
- }
- return string(b.buf[:b.w])
-}
-
-// Clean returns the shortest path name equivalent to path
-// by purely lexical processing. It applies the following rules
-// iteratively until no further processing can be done:
-//
-// 1. Replace multiple slashes with a single slash.
-// 2. Eliminate each . path name element (the current directory).
-// 3. Eliminate each inner .. path name element (the parent directory)
-// along with the non-.. element that precedes it.
-// 4. Eliminate .. elements that begin a rooted path:
-// that is, replace "/.." by "/" at the beginning of a path.
-//
-// The returned path ends in a slash only if it is the root "/".
-//
-// If the result of this process is an empty string, Clean
-// returns the string ".".
-//
-// See also Rob Pike, ``Lexical File Names in Plan 9 or
-// Getting Dot-Dot Right,''
-// http://plan9.bell-labs.com/sys/doc/lexnames.html
-func Clean(path string) string {
- if path == "" {
- return "."
- }
-
- rooted := path[0] == '/'
- n := len(path)
-
- // Invariants:
- // reading from path; r is index of next byte to process.
- // writing to buf; w is index of next byte to write.
- // dotdot is index in buf where .. must stop, either because
- // it is the leading slash or it is a leading ../../.. prefix.
- out := lazybuf{s: path}
- r, dotdot := 0, 0
- if rooted {
- out.append('/')
- r, dotdot = 1, 1
- }
-
- for r < n {
- switch {
- case path[r] == '/':
- // empty path element
- r++
- case path[r] == '.' && (r+1 == n || path[r+1] == '/'):
- // . element
- r++
- case path[r] == '.' && path[r+1] == '.' && (r+2 == n || path[r+2] == '/'):
- // .. element: remove to last /
- r += 2
- switch {
- case out.w > dotdot:
- // can backtrack
- out.w--
- for out.w > dotdot && out.index(out.w) != '/' {
- out.w--
- }
- case !rooted:
- // cannot backtrack, but not rooted, so append .. element.
- if out.w > 0 {
- out.append('/')
- }
- out.append('.')
- out.append('.')
- dotdot = out.w
- }
- default:
- // real path element.
- // add slash if needed
- if rooted && out.w != 1 || !rooted && out.w != 0 {
- out.append('/')
- }
- // copy element
- for ; r < n && path[r] != '/'; r++ {
- out.append(path[r])
- }
- }
- }
-
- // Turn empty string into "."
- if out.w == 0 {
- return "."
- }
-
- return out.string()
-}
-
-// Split splits path immediately following the final slash.
-// separating it into a directory and file name component.
-// If there is no slash path, Split returns an empty dir and
-// file set to path.
-// The returned values have the property that path = dir+file.
-func Split(path string) (dir, file string) {
- i := strings.LastIndex(path, "/")
- return path[:i+1], path[i+1:]
-}
-
-// Join joins any number of path elements into a single path, adding a
-// separating slash if necessary. The result is Cleaned; in particular,
-// all empty strings are ignored.
-func Join(elem ...string) string {
- for i, e := range elem {
- if e != "" {
- return Clean(strings.Join(elem[i:], "/"))
- }
- }
- return ""
-}
-
-// Ext returns the file name extension used by path.
-// The extension is the suffix beginning at the final dot
-// in the final slash-separated element of path;
-// it is empty if there is no dot.
-func Ext(path string) string {
- for i := len(path) - 1; i >= 0 && path[i] != '/'; i-- {
- if path[i] == '.' {
- return path[i:]
- }
- }
- return ""
-}
-
-// Base returns the last element of path.
-// Trailing slashes are removed before extracting the last element.
-// If the path is empty, Base returns ".".
-// If the path consists entirely of slashes, Base returns "/".
-func Base(path string) string {
- if path == "" {
- return "."
- }
- // Strip trailing slashes.
- for len(path) > 0 && path[len(path)-1] == '/' {
- path = path[0 : len(path)-1]
- }
- // Find the last element
- if i := strings.LastIndex(path, "/"); i >= 0 {
- path = path[i+1:]
- }
- // If empty now, it had only slashes.
- if path == "" {
- return "/"
- }
- return path
-}
-
-// IsAbs returns true if the path is absolute.
-func IsAbs(path string) bool {
- return len(path) > 0 && path[0] == '/'
-}
-
-// Dir returns all but the last element of path, typically the path's directory.
-// After dropping the final element using Split, the path is Cleaned and trailing
-// slashes are removed.
-// If the path is empty, Dir returns ".".
-// If the path consists entirely of slashes followed by non-slash bytes, Dir
-// returns a single slash. In any other case, the returned path does not end in a
-// slash.
-func Dir(path string) string {
- dir, _ := Split(path)
- dir = Clean(dir)
- last := len(dir) - 1
- if last > 0 && dir[last] == '/' {
- dir = dir[:last]
- }
- if dir == "" {
- dir = "."
- }
- return dir
-}