golang path_windows 代码
文件路径：/src/path/filepath/path_windows.go
/ Copyright 2010 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 filepath
import (
"strings"
"syscall"
)
func isSlash(c uint8) bool {
return c == '\\' || c == '/'
}
/ reservedNames lists reserved Windows names. Search for PRN in
/ https://docs.microsoft.com/en-us/windows/desktop/fileio/naming-a-file
/ for details.
var reservedNames = []string{
"CON", "PRN", "AUX", "NUL",
"COM1", "COM2", "COM3", "COM4", "COM5", "COM6", "COM7", "COM8", "COM9",
"LPT1", "LPT2", "LPT3", "LPT4", "LPT5", "LPT6", "LPT7", "LPT8", "LPT9",
}
/ isReservedName returns true, if path is Windows reserved name.
/ See reservedNames for the full list.
func isReservedName(path string) bool {
if len(path) == 0 {
return false
}
for _, reserved := range reservedNames {
if strings.EqualFold(path, reserved) {
return true
}
}
return false
}
/ IsAbs reports whether the path is absolute.
func IsAbs(path string) (b bool) {
if isReservedName(path) {
return true
}
l := volumeNameLen(path)
if l == 0 {
return false
}
/ If the volume name starts with a double slash, this is a UNC path.
if isSlash(path[0]) && isSlash(path[1]) {
return true
}
path = path[l:]
if path == "" {
return false
}
return isSlash(path[0])
}
/ volumeNameLen returns length of the leading volume name on Windows.
/ It returns 0 elsewhere.
func volumeNameLen(path string) int {
if len(path) < 2 {
return 0
}
/ with drive letter
c := path[0]
if path[1] == ':' && ('a' <= c && c <= 'z' || 'A' <= c && c <= 'Z') {
return 2
}
/ is it UNC? https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247(v=vs.85).aspx
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 n
}
break
}
}
}
return 0
}
/ HasPrefix exists for historical compatibility and should not be used.
/
/ Deprecated: HasPrefix does not respect path boundaries and
/ does not ignore case when required.
func HasPrefix(p, prefix string) bool {
if strings.HasPrefix(p, prefix) {
return true
}
return strings.HasPrefix(strings.ToLower(p), strings.ToLower(prefix))
}
func splitList(path string) []string {
/ The same implementation is used in LookPath in os/exec;
/ consider changing os/exec when changing this.
if path == "" {
return []string{}
}
/ Split path, respecting but preserving quotes.
list := []string{}
start := 0
quo := false
for i := 0; i < len(path); i++ {
switch c := path[i]; {
case c == '"':
quo = !quo
case c == ListSeparator && !quo:
list = append(list, path[start:i])
start = i + 1
}
}
list = append(list, path[start:])
/ Remove quotes.
for i, s := range list {
list[i] = strings.ReplaceAll(s, `"`, ``)
}
return list
}
func abs(path string) (string, error) {
if path == "" {
/ syscall.FullPath returns an error on empty path, because it's not a valid path.
/ To implement Abs behavior of returning working directory on empty string input,
/ special-case empty path by changing it to "." path. See golang.org/issue/24441.
path = "."
}
fullPath, err := syscall.FullPath(path)
if err != nil {
return "", err
}
return Clean(fullPath), nil
}
func join(elem []string) string {
for i, e := range elem {
if e != "" {
return joinNonEmpty(elem[i:])
}
}
return ""
}
/ joinNonEmpty is like join, but it assumes that the first element is non-empty.
func joinNonEmpty(elem []string) string {
if len(elem[0]) == 2 && elem[0][1] == ':' {
/ First element is drive letter without terminating slash.
/ Keep path relative to current directory on that drive.
/ Skip empty elements.
i := 1
for ; i < len(elem); i++ {
if elem[i] != "" {
break
}
}
return Clean(elem[0] + strings.Join(elem[i:], string(Separator)))
}
/ The following logic prevents Join from inadvertently creating a
/ UNC path on Windows. Unless the first element is a UNC path, Join
/ shouldn't create a UNC path. See golang.org/issue/9167.
p := Clean(strings.Join(elem, string(Separator)))
if !isUNC(p) {
return p
}
/ p == UNC only allowed when the first element is a UNC path.
head := Clean(elem[0])
if isUNC(head) {
return p
}
/ head + tail == UNC, but joining two non-UNC paths should not result
/ in a UNC path. Undo creation of UNC path.
tail := Clean(strings.Join(elem[1:], string(Separator)))
if head[len(head)-1] == Separator {
return head + tail
}
return head + string(Separator) + tail
}
/ isUNC reports whether path is a UNC path.
func isUNC(path string) bool {
return volumeNameLen(path) > 2
}
func sameWord(a, b string) bool {
return strings.EqualFold(a, b)
}