From b64202bc29b9c1cf0118878d1c0acc9cdb2308f6 Mon Sep 17 00:00:00 2001 From: Russ Cox Date: Mon, 6 Jul 2020 11:27:12 -0400 Subject: io/fs: add Glob and GlobFS Add Glob helper function, GlobFS interface, and test. Add Glob method to fstest.MapFS. Add testing of Glob method to fstest.TestFS. For #41190. Change-Id: If89dd7f63e310ba5ca2651340267a9ff39fcc0c7 Reviewed-on: https://go-review.googlesource.com/c/go/+/243915 Trust: Russ Cox Reviewed-by: Rob Pike --- src/io/fs/glob.go | 116 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 116 insertions(+) create mode 100644 src/io/fs/glob.go (limited to 'src/io/fs/glob.go') diff --git a/src/io/fs/glob.go b/src/io/fs/glob.go new file mode 100644 index 0000000000..77f6ebbaaf --- /dev/null +++ b/src/io/fs/glob.go @@ -0,0 +1,116 @@ +// 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 fs + +import ( + "path" + "runtime" +) + +// A GlobFS is a file system with a Glob method. +type GlobFS interface { + FS + + // Glob returns the names of all files matching pattern, + // providing an implementation of the top-level + // Glob function. + Glob(pattern string) ([]string, error) +} + +// 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 path.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 path.ErrBadPattern, reporting that +// the pattern is malformed. +// +// If fs implements GlobFS, Glob calls fs.Glob. +// Otherwise, Glob uses ReadDir to traverse the directory tree +// and look for matches for the pattern. +func Glob(fsys FS, pattern string) (matches []string, err error) { + if fsys, ok := fsys.(GlobFS); ok { + return fsys.Glob(pattern) + } + + if !hasMeta(pattern) { + if _, err = Stat(fsys, pattern); err != nil { + return nil, nil + } + return []string{pattern}, nil + } + + dir, file := path.Split(pattern) + dir = cleanGlobPath(dir) + + if !hasMeta(dir) { + return glob(fsys, dir, file, nil) + } + + // Prevent infinite recursion. See issue 15879. + if dir == pattern { + return nil, path.ErrBadPattern + } + + var m []string + m, err = Glob(fsys, dir) + if err != nil { + return + } + for _, d := range m { + matches, err = glob(fsys, d, file, matches) + if err != nil { + return + } + } + return +} + +// cleanGlobPath prepares path for glob matching. +func cleanGlobPath(path string) string { + switch path { + case "": + return "." + default: + return path[0 : len(path)-1] // chop off trailing separator + } +} + +// glob searches for files matching pattern in the directory dir +// and appends them to matches, returning the updated slice. +// If the directory cannot be opened, glob returns the existing matches. +// New matches are added in lexicographical order. +func glob(fs FS, dir, pattern string, matches []string) (m []string, e error) { + m = matches + infos, err := ReadDir(fs, dir) + if err != nil { + return // ignore I/O error + } + + for _, info := range infos { + n := info.Name() + matched, err := path.Match(pattern, n) + if err != nil { + return m, err + } + if matched { + m = append(m, path.Join(dir, n)) + } + } + return +} + +// hasMeta reports whether path contains any of the magic characters +// recognized by path.Match. +func hasMeta(path string) bool { + for i := 0; i < len(path); i++ { + c := path[i] + if c == '*' || c == '?' || c == '[' || runtime.GOOS == "windows" && c == '\\' { + return true + } + } + return false +} -- cgit v1.2.1 From b5ddc42b465dd5b9532ee336d98343d81a6d35b2 Mon Sep 17 00:00:00 2001 From: Russ Cox Date: Thu, 22 Oct 2020 12:11:29 -0400 Subject: io/fs, path, path/filepath, testing/fstest: validate patterns in Match, Glob According to #28614, proposal review agreed in December 2018 that Match should return an error for failed matches where the unmatched part of the pattern has a syntax error. (The failed match has to date caused the scan of the pattern to stop early.) This change implements that behavior: the match loop continues scanning to the end of the pattern, even after a confirmed mismatch, to check whether the pattern is even well-formed. The change applies to both path.Match and filepath.Match. Then filepath.Glob and fs.Glob make a single validity-checking call to Match before beginning their usual processing. Also update fstest.TestFS to check for correct validation in custom Glob implementations. Fixes #28614. Change-Id: Ic1d35a4bb9c3565184ae83dbefc425c5c96318e7 Reviewed-on: https://go-review.googlesource.com/c/go/+/264397 Trust: Russ Cox Reviewed-by: Rob Pike --- src/io/fs/glob.go | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'src/io/fs/glob.go') diff --git a/src/io/fs/glob.go b/src/io/fs/glob.go index 77f6ebbaaf..cde6c49f3d 100644 --- a/src/io/fs/glob.go +++ b/src/io/fs/glob.go @@ -36,6 +36,10 @@ func Glob(fsys FS, pattern string) (matches []string, err error) { return fsys.Glob(pattern) } + // Check pattern is well-formed. + if _, err := path.Match(pattern, ""); err != nil { + return nil, err + } if !hasMeta(pattern) { if _, err = Stat(fsys, pattern); err != nil { return nil, nil -- cgit v1.2.1