summaryrefslogtreecommitdiffstats
path: root/src/path/filepath/match.go
diff options
context:
space:
mode:
Diffstat (limited to 'src/path/filepath/match.go')
-rw-r--r--src/path/filepath/match.go360
1 files changed, 360 insertions, 0 deletions
diff --git a/src/path/filepath/match.go b/src/path/filepath/match.go
new file mode 100644
index 0000000..c77a269
--- /dev/null
+++ b/src/path/filepath/match.go
@@ -0,0 +1,360 @@
+// 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 (
+ "errors"
+ "os"
+ "runtime"
+ "sort"
+ "strings"
+ "unicode/utf8"
+)
+
+// ErrBadPattern indicates a pattern was malformed.
+var ErrBadPattern = errors.New("syntax error in pattern")
+
+// Match reports whether name matches the shell file name pattern.
+// The pattern syntax is:
+//
+// pattern:
+// { term }
+// term:
+// '*' matches any sequence of non-Separator characters
+// '?' matches any single non-Separator character
+// '[' [ '^' ] { character-range } ']'
+// character class (must be non-empty)
+// c matches character c (c != '*', '?', '\\', '[')
+// '\\' c matches character c
+//
+// character-range:
+// c matches character c (c != '\\', '-', ']')
+// '\\' c matches character c
+// lo '-' hi matches character c for lo <= c <= hi
+//
+// Match requires pattern to match all of name, not just a substring.
+// The only possible returned error is ErrBadPattern, when pattern
+// is malformed.
+//
+// On Windows, escaping is disabled. Instead, '\\' is treated as
+// path separator.
+//
+func Match(pattern, name string) (matched bool, err error) {
+Pattern:
+ for len(pattern) > 0 {
+ var star bool
+ var chunk string
+ star, chunk, pattern = scanChunk(pattern)
+ if star && chunk == "" {
+ // Trailing * matches rest of string unless it has a /.
+ return !strings.Contains(name, string(Separator)), nil
+ }
+ // Look for match at current position.
+ t, ok, err := matchChunk(chunk, name)
+ // if we're the last chunk, make sure we've exhausted the name
+ // otherwise we'll give a false result even if we could still match
+ // using the star
+ if ok && (len(t) == 0 || len(pattern) > 0) {
+ name = t
+ continue
+ }
+ if err != nil {
+ return false, err
+ }
+ if star {
+ // Look for match skipping i+1 bytes.
+ // Cannot skip /.
+ for i := 0; i < len(name) && name[i] != Separator; i++ {
+ t, ok, err := matchChunk(chunk, name[i+1:])
+ if ok {
+ // if we're the last chunk, make sure we exhausted the name
+ if len(pattern) == 0 && len(t) > 0 {
+ continue
+ }
+ name = t
+ continue Pattern
+ }
+ if err != nil {
+ return false, err
+ }
+ }
+ }
+ return false, nil
+ }
+ return len(name) == 0, nil
+}
+
+// scanChunk gets the next segment of pattern, which is a non-star string
+// possibly preceded by a star.
+func scanChunk(pattern string) (star bool, chunk, rest string) {
+ for len(pattern) > 0 && pattern[0] == '*' {
+ pattern = pattern[1:]
+ star = true
+ }
+ inrange := false
+ var i int
+Scan:
+ for i = 0; i < len(pattern); i++ {
+ switch pattern[i] {
+ case '\\':
+ if runtime.GOOS != "windows" {
+ // error check handled in matchChunk: bad pattern.
+ if i+1 < len(pattern) {
+ i++
+ }
+ }
+ case '[':
+ inrange = true
+ case ']':
+ inrange = false
+ case '*':
+ if !inrange {
+ break Scan
+ }
+ }
+ }
+ return star, pattern[0:i], pattern[i:]
+}
+
+// matchChunk checks whether chunk matches the beginning of s.
+// If so, it returns the remainder of s (after the match).
+// Chunk is all single-character operators: literals, char classes, and ?.
+func matchChunk(chunk, s string) (rest string, ok bool, err error) {
+ // failed records whether the match has failed.
+ // After the match fails, the loop continues on processing chunk,
+ // checking that the pattern is well-formed but no longer reading s.
+ failed := false
+ for len(chunk) > 0 {
+ if !failed && len(s) == 0 {
+ failed = true
+ }
+ switch chunk[0] {
+ case '[':
+ // character class
+ var r rune
+ if !failed {
+ var n int
+ r, n = utf8.DecodeRuneInString(s)
+ s = s[n:]
+ }
+ chunk = chunk[1:]
+ // possibly negated
+ negated := false
+ if len(chunk) > 0 && chunk[0] == '^' {
+ negated = true
+ chunk = chunk[1:]
+ }
+ // parse all ranges
+ match := false
+ nrange := 0
+ for {
+ if len(chunk) > 0 && chunk[0] == ']' && nrange > 0 {
+ chunk = chunk[1:]
+ break
+ }
+ var lo, hi rune
+ if lo, chunk, err = getEsc(chunk); err != nil {
+ return "", false, err
+ }
+ hi = lo
+ if chunk[0] == '-' {
+ if hi, chunk, err = getEsc(chunk[1:]); err != nil {
+ return "", false, err
+ }
+ }
+ if lo <= r && r <= hi {
+ match = true
+ }
+ nrange++
+ }
+ if match == negated {
+ failed = true
+ }
+
+ case '?':
+ if !failed {
+ if s[0] == Separator {
+ failed = true
+ }
+ _, n := utf8.DecodeRuneInString(s)
+ s = s[n:]
+ }
+ chunk = chunk[1:]
+
+ case '\\':
+ if runtime.GOOS != "windows" {
+ chunk = chunk[1:]
+ if len(chunk) == 0 {
+ return "", false, ErrBadPattern
+ }
+ }
+ fallthrough
+
+ default:
+ if !failed {
+ if chunk[0] != s[0] {
+ failed = true
+ }
+ s = s[1:]
+ }
+ chunk = chunk[1:]
+ }
+ }
+ if failed {
+ return "", false, nil
+ }
+ return s, true, nil
+}
+
+// getEsc gets a possibly-escaped character from chunk, for a character class.
+func getEsc(chunk string) (r rune, nchunk string, err error) {
+ if len(chunk) == 0 || chunk[0] == '-' || chunk[0] == ']' {
+ err = ErrBadPattern
+ return
+ }
+ if chunk[0] == '\\' && runtime.GOOS != "windows" {
+ chunk = chunk[1:]
+ if len(chunk) == 0 {
+ err = ErrBadPattern
+ return
+ }
+ }
+ r, n := utf8.DecodeRuneInString(chunk)
+ if r == utf8.RuneError && n == 1 {
+ err = ErrBadPattern
+ }
+ nchunk = chunk[n:]
+ if len(nchunk) == 0 {
+ err = ErrBadPattern
+ }
+ return
+}
+
+// Glob returns the names of all files matching pattern or nil
+// if there is no matching file. The syntax of patterns is the same
+// as in Match. The pattern may describe hierarchical names such as
+// /usr/*/bin/ed (assuming the Separator is '/').
+//
+// Glob ignores file system errors such as I/O errors reading directories.
+// The only possible returned error is ErrBadPattern, when pattern
+// is malformed.
+func Glob(pattern string) (matches []string, err error) {
+ // Check pattern is well-formed.
+ if _, err := Match(pattern, ""); err != nil {
+ return nil, err
+ }
+ if !hasMeta(pattern) {
+ if _, err = os.Lstat(pattern); err != nil {
+ return nil, nil
+ }
+ return []string{pattern}, nil
+ }
+
+ dir, file := Split(pattern)
+ volumeLen := 0
+ if runtime.GOOS == "windows" {
+ volumeLen, dir = cleanGlobPathWindows(dir)
+ } else {
+ dir = cleanGlobPath(dir)
+ }
+
+ if !hasMeta(dir[volumeLen:]) {
+ return glob(dir, file, nil)
+ }
+
+ // Prevent infinite recursion. See issue 15879.
+ if dir == pattern {
+ return nil, ErrBadPattern
+ }
+
+ var m []string
+ m, err = Glob(dir)
+ if err != nil {
+ return
+ }
+ for _, d := range m {
+ matches, err = glob(d, file, matches)
+ if err != nil {
+ return
+ }
+ }
+ return
+}
+
+// cleanGlobPath prepares path for glob matching.
+func cleanGlobPath(path string) string {
+ switch path {
+ case "":
+ return "."
+ case string(Separator):
+ // do nothing to the path
+ return path
+ default:
+ return path[0 : len(path)-1] // chop off trailing separator
+ }
+}
+
+// cleanGlobPathWindows is windows version of cleanGlobPath.
+func cleanGlobPathWindows(path string) (prefixLen int, cleaned string) {
+ vollen := volumeNameLen(path)
+ switch {
+ case path == "":
+ return 0, "."
+ case vollen+1 == len(path) && os.IsPathSeparator(path[len(path)-1]): // /, \, C:\ and C:/
+ // do nothing to the path
+ return vollen + 1, path
+ case vollen == len(path) && len(path) == 2: // C:
+ return vollen, path + "." // convert C: into C:.
+ default:
+ if vollen >= len(path) {
+ vollen = len(path) - 1
+ }
+ return vollen, path[0 : len(path)-1] // chop off trailing separator
+ }
+}
+
+// glob searches for files matching pattern in the directory dir
+// and appends them to matches. If the directory cannot be
+// opened, it returns the existing matches. New matches are
+// added in lexicographical order.
+func glob(dir, pattern string, matches []string) (m []string, e error) {
+ m = matches
+ fi, err := os.Stat(dir)
+ if err != nil {
+ return // ignore I/O error
+ }
+ if !fi.IsDir() {
+ return // ignore I/O error
+ }
+ d, err := os.Open(dir)
+ if err != nil {
+ return // ignore I/O error
+ }
+ defer d.Close()
+
+ names, _ := d.Readdirnames(-1)
+ sort.Strings(names)
+
+ for _, n := range names {
+ matched, err := Match(pattern, n)
+ if err != nil {
+ return m, err
+ }
+ if matched {
+ m = append(m, Join(dir, n))
+ }
+ }
+ return
+}
+
+// hasMeta reports whether path contains any of the magic characters
+// recognized by Match.
+func hasMeta(path string) bool {
+ magicChars := `*?[`
+ if runtime.GOOS != "windows" {
+ magicChars = `*?[\`
+ }
+ return strings.ContainsAny(path, magicChars)
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-26 00:43:40 +0000