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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:16:40 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:16:40 +0000
commit47ab3d4a42e9ab51c465c4322d2ec233f6324e6b (patch)
treea61a0ffd83f4a3def4b36e5c8e99630c559aa723 /misc/cgo/testcarchive/overlaydir_test.go
parentInitial commit. (diff)
downloadgolang-1.18-upstream.tar.xz
golang-1.18-upstream.zip
Adding upstream version 1.18.10.upstream/1.18.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'misc/cgo/testcarchive/overlaydir_test.go')
-rw-r--r--misc/cgo/testcarchive/overlaydir_test.go78
1 files changed, 78 insertions, 0 deletions
diff --git a/misc/cgo/testcarchive/overlaydir_test.go b/misc/cgo/testcarchive/overlaydir_test.go
new file mode 100644
index 0000000..67974c5
--- /dev/null
+++ b/misc/cgo/testcarchive/overlaydir_test.go
@@ -0,0 +1,78 @@
+// Copyright 2019 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 carchive_test
+
+import (
+ "io"
+ "os"
+ "path/filepath"
+ "strings"
+)
+
+// overlayDir makes a minimal-overhead copy of srcRoot in which new files may be added.
+//
+// TODO: Once we no longer need to support the misc module in GOPATH mode,
+// factor this function out into a package to reduce duplication.
+func overlayDir(dstRoot, srcRoot string) error {
+ dstRoot = filepath.Clean(dstRoot)
+ if err := os.MkdirAll(dstRoot, 0777); err != nil {
+ return err
+ }
+
+ srcRoot, err := filepath.Abs(srcRoot)
+ if err != nil {
+ return err
+ }
+
+ return filepath.Walk(srcRoot, func(srcPath string, info os.FileInfo, err error) error {
+ if err != nil || srcPath == srcRoot {
+ return err
+ }
+
+ suffix := strings.TrimPrefix(srcPath, srcRoot)
+ for len(suffix) > 0 && suffix[0] == filepath.Separator {
+ suffix = suffix[1:]
+ }
+ dstPath := filepath.Join(dstRoot, suffix)
+
+ perm := info.Mode() & os.ModePerm
+ if info.Mode()&os.ModeSymlink != 0 {
+ info, err = os.Stat(srcPath)
+ if err != nil {
+ return err
+ }
+ perm = info.Mode() & os.ModePerm
+ }
+
+ // Always copy directories (don't symlink them).
+ // If we add a file in the overlay, we don't want to add it in the original.
+ if info.IsDir() {
+ return os.MkdirAll(dstPath, perm|0200)
+ }
+
+ // If the OS supports symlinks, use them instead of copying bytes.
+ if err := os.Symlink(srcPath, dstPath); err == nil {
+ return nil
+ }
+
+ // Otherwise, copy the bytes.
+ src, err := os.Open(srcPath)
+ if err != nil {
+ return err
+ }
+ defer src.Close()
+
+ dst, err := os.OpenFile(dstPath, os.O_WRONLY|os.O_CREATE|os.O_EXCL, perm)
+ if err != nil {
+ return err
+ }
+
+ _, err = io.Copy(dst, src)
+ if closeErr := dst.Close(); err == nil {
+ err = closeErr
+ }
+ return err
+ })
+}