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Diffstat (limited to '')
2 files changed, 374 insertions, 0 deletions
diff --git a/dependencies/pkg/mod/golang.org/x/exp@v0.0.0-20220613132600-b0d781184e0d/cmd/txtar/txtar.go b/dependencies/pkg/mod/golang.org/x/exp@v0.0.0-20220613132600-b0d781184e0d/cmd/txtar/txtar.go new file mode 100644 index 0000000..9beb163 --- /dev/null +++ b/dependencies/pkg/mod/golang.org/x/exp@v0.0.0-20220613132600-b0d781184e0d/cmd/txtar/txtar.go @@ -0,0 +1,196 @@ +// Copyright 2020 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. + +// The txtar command writes or extracts a text-based file archive in the format +// provided by the golang.org/x/tools/txtar package. +// +// The default behavior is to read a comment from stdin and write the archive +// file containing the recursive contents of the named files and directories, +// including hidden files, to stdout. Any non-flag arguments to the command name +// the files and/or directories to include, with the contents of directories +// included recursively. An empty argument list is equivalent to ".". +// +// The --extract (or -x) flag instructs txtar to instead read the archive file +// from stdin and extract all of its files to corresponding locations relative +// to the current, writing the archive's comment to stdout. +// +// Archive files are by default extracted only to the current directory or its +// subdirectories. To allow extracting outside the current directory, use the +// --unsafe flag. +// +// Shell variables in paths are expanded (using os.Expand) if the corresponding +// variable is set in the process environment. When writing an archive, the +// variables (before expansion) are preserved in the archived paths. +// +// Example usage: +// +// txtar *.go <README >testdata/example.txt +// +// txtar --extract <playground_example.txt >main.go +package main + +import ( + "bytes" + "flag" + "fmt" + "io/ioutil" + "os" + "path" + "path/filepath" + "regexp" + "strings" + "time" + + "golang.org/x/tools/txtar" +) + +var ( + extractFlag = flag.Bool("extract", false, "if true, extract files from the archive instead of writing to it") + unsafeFlag = flag.Bool("unsafe", false, "allow extraction of files outside the current directory") +) + +func init() { + flag.BoolVar(extractFlag, "x", *extractFlag, "short alias for --extract") +} + +func main() { + flag.Parse() + + var err error + if *extractFlag { + if len(flag.Args()) > 0 { + fmt.Fprintln(os.Stderr, "Usage: txtar --extract <archive.txt") + os.Exit(2) + } + err = extract() + } else { + paths := flag.Args() + if len(paths) == 0 { + paths = []string{"."} + } + err = archive(paths) + } + + if err != nil { + fmt.Fprintf(os.Stderr, "Error: %v\n", err) + os.Exit(1) + } +} + +func extract() (err error) { + b, err := ioutil.ReadAll(os.Stdin) + if err != nil { + return err + } + + ar := txtar.Parse(b) + + if !*unsafeFlag { + // Check that no files are extracted outside the current directory + wd, err := os.Getwd() + if err != nil { + return err + } + // Add trailing separator to terminate wd. + // This prevents extracting to outside paths which prefix wd, + // e.g. extracting to /home/foobar when wd is /home/foo + if !strings.HasSuffix(wd, string(filepath.Separator)) { + wd += string(filepath.Separator) + } + + for _, f := range ar.Files { + fileName := filepath.Clean(expand(f.Name)) + + if strings.HasPrefix(fileName, "..") || + (filepath.IsAbs(fileName) && !strings.HasPrefix(fileName, wd)) { + return fmt.Errorf("file path '%s' is outside the current directory", f.Name) + } + } + } + + for _, f := range ar.Files { + fileName := filepath.FromSlash(path.Clean(expand(f.Name))) + if err := os.MkdirAll(filepath.Dir(fileName), 0777); err != nil { + return err + } + if err := ioutil.WriteFile(fileName, f.Data, 0666); err != nil { + return err + } + } + + if len(ar.Comment) > 0 { + os.Stdout.Write(ar.Comment) + } + return nil +} + +func archive(paths []string) (err error) { + txtarHeader := regexp.MustCompile(`(?m)^-- .* --$`) + + ar := new(txtar.Archive) + for _, p := range paths { + root := filepath.Clean(expand(p)) + prefix := root + string(filepath.Separator) + err := filepath.Walk(root, func(fileName string, info os.FileInfo, err error) error { + if err != nil || info.IsDir() { + return err + } + + suffix := "" + if fileName != root { + suffix = strings.TrimPrefix(fileName, prefix) + } + name := filepath.ToSlash(filepath.Join(p, suffix)) + + data, err := ioutil.ReadFile(fileName) + if err != nil { + return err + } + if txtarHeader.Match(data) { + return fmt.Errorf("cannot archive %s: file contains a txtar header", name) + } + + ar.Files = append(ar.Files, txtar.File{Name: name, Data: data}) + return nil + }) + if err != nil { + return err + } + } + + // After we have read all of the source files, read the comment from stdin. + // + // Wait until the read has been blocked for a while before prompting the user + // to enter it: if they are piping the comment in from some other file, the + // read should complete very quickly and there is no need for a prompt. + // (200ms is typically long enough to read a reasonable comment from the local + // machine, but short enough that humans don't notice it.) + // + // Don't prompt until we have successfully read the other files: + // if we encountered an error, we don't need to ask for a comment. + timer := time.AfterFunc(200*time.Millisecond, func() { + fmt.Fprintln(os.Stderr, "Enter comment:") + }) + comment, err := ioutil.ReadAll(os.Stdin) + timer.Stop() + if err != nil { + return fmt.Errorf("reading comment from %s: %v", os.Stdin.Name(), err) + } + ar.Comment = bytes.TrimSpace(comment) + + _, err = os.Stdout.Write(txtar.Format(ar)) + return err +} + +// expand is like os.ExpandEnv, but preserves unescaped variables (instead +// of escaping them to the empty string) if the variable is not set. +func expand(p string) string { + return os.Expand(p, func(key string) string { + v, ok := os.LookupEnv(key) + if !ok { + return "$" + key + } + return v + }) +} diff --git a/dependencies/pkg/mod/golang.org/x/exp@v0.0.0-20220613132600-b0d781184e0d/cmd/txtar/txtar_test.go b/dependencies/pkg/mod/golang.org/x/exp@v0.0.0-20220613132600-b0d781184e0d/cmd/txtar/txtar_test.go new file mode 100644 index 0000000..ea9f2bf --- /dev/null +++ b/dependencies/pkg/mod/golang.org/x/exp@v0.0.0-20220613132600-b0d781184e0d/cmd/txtar/txtar_test.go @@ -0,0 +1,178 @@ +// Copyright 2020 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 main_test + +import ( + "fmt" + "io/ioutil" + "os" + "os/exec" + "path/filepath" + "runtime" + "strings" + "sync" + "testing" +) + +const comment = "This is a txtar archive.\n" + +const testdata = `This is a txtar archive. +-- one.txt -- +one +-- dir/two.txt -- +two +-- $SPECIAL_LOCATION/three.txt -- +three +` + +func TestMain(m *testing.M) { + code := m.Run() + txtarBin.once.Do(func() {}) + if txtarBin.name != "" { + os.Remove(txtarBin.name) + } + os.Exit(code) +} + +func TestRoundTrip(t *testing.T) { + os.Setenv("SPECIAL_LOCATION", "special") + defer os.Unsetenv("SPECIAL_LOCATION") + + // Expand the testdata archive into a temporary directory. + parentDir, err := ioutil.TempDir("", "txtar") + if err != nil { + t.Fatal(err) + } + defer os.RemoveAll(parentDir) + dir := filepath.Join(parentDir, "dir") + if err := os.Mkdir(dir, 0755); err != nil { + t.Fatal(err) + } + if out, err := txtar(t, dir, testdata, "--extract"); err != nil { + t.Fatal(err) + } else if out != comment { + t.Fatalf("txtar --extract: stdout:\n%s\nwant:\n%s", out, comment) + } + + // Now, re-archive its contents explicitly and ensure that the result matches + // the original. + args := []string{"one.txt", "dir", "$SPECIAL_LOCATION"} + if out, err := txtar(t, dir, comment, args...); err != nil { + t.Fatal(err) + } else if out != testdata { + t.Fatalf("txtar %s: archive:\n%s\n\nwant:\n%s", strings.Join(args, " "), out, testdata) + } +} + +func TestUnsafePaths(t *testing.T) { + // Set up temporary directories for test archives. + parentDir, err := ioutil.TempDir("", "txtar") + if err != nil { + t.Fatal(err) + } + defer os.RemoveAll(parentDir) + dir := filepath.Join(parentDir, "dir") + if err := os.Mkdir(dir, 0755); err != nil { + t.Fatal(err) + } + + // Test --unsafe option for both absolute and relative paths + testcases := []struct{ name, path string }{ + {"Absolute", filepath.Join(parentDir, "dirSpecial")}, + {"Relative", "../special"}, + } + + for _, tc := range testcases { + t.Run(tc.name, func(t *testing.T) { + // Set SPECIAL_LOCATION outside the current directory + t.Setenv("SPECIAL_LOCATION", tc.path) + + // Expand the testdata archive into a temporary directory. + + // Should fail without the --unsafe flag + if _, err := txtar(t, dir, testdata, "--extract"); err == nil { + t.Fatalf("txtar --extract: extracts to unsafe paths") + } + + // Should allow paths outside the current dir with the --unsafe flags + out, err := txtar(t, dir, testdata, "--extract", "--unsafe") + if err != nil { + t.Fatal(err) + } + if out != comment { + t.Fatalf("txtar --extract --unsafe: stdout:\n%s\nwant:\n%s", out, comment) + } + + // Now, re-archive its contents explicitly and ensure that the result matches + // the original. + args := []string{"one.txt", "dir", "$SPECIAL_LOCATION"} + out, err = txtar(t, dir, comment, args...) + if err != nil { + t.Fatal(err) + } + if out != testdata { + t.Fatalf("txtar %s: archive:\n%s\n\nwant:\n%s", strings.Join(args, " "), out, testdata) + } + }) + } +} + +// txtar runs the txtar command in the given directory with the given input and +// arguments. +func txtar(t *testing.T, dir, input string, args ...string) (string, error) { + t.Helper() + cmd := exec.Command(txtarName(t), args...) + cmd.Dir = dir + cmd.Env = append(os.Environ(), "PWD="+dir) + cmd.Stdin = strings.NewReader(input) + stderr := new(strings.Builder) + cmd.Stderr = stderr + out, err := cmd.Output() + if err != nil { + return "", fmt.Errorf("%s: %v\n%s", strings.Join(cmd.Args, " "), err, stderr) + } + if stderr.String() != "" { + t.Logf("OK: %s\n%s", strings.Join(cmd.Args, " "), stderr) + } + return string(out), nil +} + +var txtarBin struct { + once sync.Once + name string + err error +} + +// txtarName returns the name of the txtar executable, building it if needed. +func txtarName(t *testing.T) string { + t.Helper() + if _, err := exec.LookPath("go"); err != nil { + t.Skipf("cannot build txtar binary: %v", err) + } + + txtarBin.once.Do(func() { + exe, err := ioutil.TempFile("", "txtar-*.exe") + if err != nil { + txtarBin.err = err + return + } + exe.Close() + txtarBin.name = exe.Name() + + cmd := exec.Command("go", "build", "-o", txtarBin.name, ".") + out, err := cmd.CombinedOutput() + if err != nil { + txtarBin.err = fmt.Errorf("%s: %v\n%s", strings.Join(cmd.Args, " "), err, out) + } + }) + + if txtarBin.err != nil { + if runtime.GOOS == "android" { + t.Skipf("skipping test after failing to build txtar binary: go_android_exec may have failed to copy needed dependencies (see https://golang.org/issue/37088)") + } + t.Fatal(txtarBin.err) + } + return txtarBin.name +} |