diff options
author | Rob Pike <r@golang.org> | 2009-05-05 17:05:39 -0700 |
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committer | Rob Pike <r@golang.org> | 2009-05-05 17:05:39 -0700 |
commit | b6708b2dad4af458e69fde7fc596ecdce03280d0 (patch) | |
tree | 11cfc1b980ecce9cb0eec06f49cc53ce05faf350 /src/lib/path.go | |
parent | 658b10477a16151de7e4d51657993f95445f11ee (diff) | |
download | golang-b6708b2dad4af458e69fde7fc596ecdce03280d0.tar.gz |
directory-per-package step 1: move files from lib/X.go to lib/X/X.go
no substantive changes except:
- new Makefiles, all auto-generated
- go/src/lib/Makefile has been extensively edited
R=rsc
OCL=28310
CL=28310
Diffstat (limited to 'src/lib/path.go')
-rw-r--r-- | src/lib/path.go | 136 |
1 files changed, 0 insertions, 136 deletions
diff --git a/src/lib/path.go b/src/lib/path.go deleted file mode 100644 index a7e2c26c3..000000000 --- a/src/lib/path.go +++ /dev/null @@ -1,136 +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. - -// The path package implements utility routines for manipulating -// slash-separated filename paths. -package path - -import "io" - -// 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. -// -// 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. - buf := io.StringBytes(path); - r, w, dotdot := 0, 0, 0; - if rooted { - r, w, dotdot = 1, 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 w > dotdot: - // can backtrack - w--; - for w > dotdot && buf[w] != '/' { - w--; - } - case !rooted: - // cannot backtrack, but not rooted, so append .. element. - if w > 0 { - buf[w] = '/'; - w++; - } - buf[w] = '.'; - w++; - buf[w] = '.'; - w++; - dotdot = w; - } - default: - // real path element. - // add slash if needed - if rooted && w != 1 || !rooted && w != 0 { - buf[w] = '/'; - w++; - } - // copy element - for ; r < n && path[r] != '/'; r++ { - buf[w] = path[r]; - w++; - } - } - } - - // Turn empty string into "." - if w == 0 { - buf[w] = '.'; - w++; - } - - return string(buf[0:w]); -} - -// Split splits path immediately following the final slash, -// separating it into a directory and file name component. -// If there is no slash in path, DirFile returns an empty dir and -// file set to path. -func Split(path string) (dir, file string) { - for i := len(path)-1; i >= 0; i-- { - if path[i] == '/' { - return path[0:i+1], path[i+1:len(path)]; - } - } - return "", path -} - -// Join joins dir and file into a single path, adding a separating -// slash if necessary. If dir is empty, it returns file. -func Join(dir, file string) string { - if dir == "" { - return file; - } - return Clean(dir + "/" + file); -} - -// 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 { - dot := -1; - for i := len(path)-1; i >= 0 && path[i] != '/'; i-- { - if path[i] == '.' { - return path[i:len(path)]; - } - } - return "" -} - |