diff options
Diffstat (limited to 'cli/internal/cacheitem/filepath.go')
| -rw-r--r-- | cli/internal/cacheitem/filepath.go | 162 |
1 files changed, 0 insertions, 162 deletions
diff --git a/cli/internal/cacheitem/filepath.go b/cli/internal/cacheitem/filepath.go deleted file mode 100644 index 4fd1681..0000000 --- a/cli/internal/cacheitem/filepath.go +++ /dev/null @@ -1,162 +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 cacheitem - -import "os" - -const _separator = os.PathSeparator - -// 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 { - path string - buf []byte - w int - volAndPath string - volLen int -} - -func (b *lazybuf) index(i int) byte { - if b.buf != nil { - return b.buf[i] - } - return b.path[i] -} - -func (b *lazybuf) append(c byte) { - if b.buf == nil { - if b.w < len(b.path) && b.path[b.w] == c { - b.w++ - return - } - b.buf = make([]byte, len(b.path)) - copy(b.buf, b.path[:b.w]) - } - b.buf[b.w] = c - b.w++ -} - -func (b *lazybuf) string() string { - if b.buf == nil { - return b.volAndPath[:b.volLen+b.w] - } - return b.volAndPath[:b.volLen] + string(b.buf[:b.w]) -} - -// Clean is extracted from stdlib and removes `FromSlash` processing -// of the stdlib version. -// -// 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 Separator elements with a single one. -// 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, -// assuming Separator is '/'. -// -// The returned path ends in a slash only if it represents a root directory, -// such as "/" on Unix or `C:\` on Windows. -// -// Finally, any occurrences of slash are replaced by Separator. -// -// 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,” -// https://9p.io/sys/doc/lexnames.html -func Clean(path string) string { - originalPath := path - volLen := volumeNameLen(path) - path = path[volLen:] - if path == "" { - if volLen > 1 && originalPath[1] != ':' { - // should be UNC - // ORIGINAL: return FromSlash(originalPath) - return originalPath - } - return originalPath + "." - } - rooted := os.IsPathSeparator(path[0]) - - // 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. - n := len(path) - out := lazybuf{path: path, volAndPath: originalPath, volLen: volLen} - r, dotdot := 0, 0 - if rooted { - out.append(_separator) - r, dotdot = 1, 1 - } - - for r < n { - switch { - case os.IsPathSeparator(path[r]): - // empty path element - r++ - case path[r] == '.' && r+1 == n: - // . element - r++ - case path[r] == '.' && os.IsPathSeparator(path[r+1]): - // ./ element - r++ - - for r < len(path) && os.IsPathSeparator(path[r]) { - r++ - } - if out.w == 0 && volumeNameLen(path[r:]) > 0 { - // When joining prefix "." and an absolute path on Windows, - // the prefix should not be removed. - out.append('.') - } - case path[r] == '.' && path[r+1] == '.' && (r+2 == n || os.IsPathSeparator(path[r+2])): - // .. element: remove to last separator - r += 2 - switch { - case out.w > dotdot: - // can backtrack - out.w-- - for out.w > dotdot && !os.IsPathSeparator(out.index(out.w)) { - out.w-- - } - case !rooted: - // cannot backtrack, but not rooted, so append .. element. - if out.w > 0 { - out.append(_separator) - } - 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(_separator) - } - // copy element - for ; r < n && !os.IsPathSeparator(path[r]); r++ { - out.append(path[r]) - } - } - } - - // Turn empty string into "." - if out.w == 0 { - out.append('.') - } - - // ORIGINAL: return FromSlash(out.string()) - return out.string() -} |