k3s/vendor/github.com/opencontainers/runtime-tools/filepath/clean.go

75 lines
1.7 KiB
Go

package filepath
import (
"fmt"
"strings"
)
// Clean is an explicit-OS version of path/filepath's Clean.
func Clean(os, path string) string {
abs := IsAbs(os, path)
sep := Separator(os)
elements := strings.Split(path, string(sep))
// Replace multiple Separator elements with a single one.
for i := 0; i < len(elements); i++ {
if len(elements[i]) == 0 {
elements = append(elements[:i], elements[i+1:]...)
i--
}
}
// Eliminate each . path name element (the current directory).
for i := 0; i < len(elements); i++ {
if elements[i] == "." && len(elements) > 1 {
elements = append(elements[:i], elements[i+1:]...)
i--
}
}
// Eliminate each inner .. path name element (the parent directory)
// along with the non-.. element that precedes it.
for i := 1; i < len(elements); i++ {
if i == 1 && abs && sep == '\\' {
continue
}
if i > 0 && elements[i] == ".." {
elements = append(elements[:i-1], elements[i+1:]...)
i -= 2
}
}
// Eliminate .. elements that begin a rooted path:
// that is, replace "/.." by "/" at the beginning of a path,
// assuming Separator is '/'.
offset := 0
if sep == '\\' {
offset = 1
}
if abs {
for len(elements) > offset && elements[offset] == ".." {
elements = append(elements[:offset], elements[offset+1:]...)
}
}
cleaned := strings.Join(elements, string(sep))
if abs {
if sep == '/' {
cleaned = fmt.Sprintf("%c%s", sep, cleaned)
} else if len(elements) == 1 {
cleaned = fmt.Sprintf("%s%c", cleaned, sep)
}
}
// If the result of this process is an empty string, Clean returns
// the string ".".
if len(cleaned) == 0 {
cleaned = "."
}
if cleaned == path {
return path
}
return Clean(os, cleaned)
}