1. docker
  2. Commit ae0a3d69186f3c2e201be7672e1c6460016d6ae1
Browse code

pkg/fileutils: move ReadSymlinkedDirectory internal to daemon

It has no external consumers, is written with specific behavior (including
some potentially surprising behavior), making it not a good candidate to
carry in the module.

This moves it internal to the daemon as a non-exported utility, so that
it's only accessible where it's currently used.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Sebastiaan van Stijn authored on 2025/07/29 18:03:10
Showing 4 changed files
daemon/containerfs_linux.go
History View file @ ae0a3d6
... ... 
@@ -18,7 +18,6 @@ import (
18 18 
 	"github.com/docker/docker/daemon/container"
19 19 
 	"github.com/docker/docker/daemon/internal/mounttree"
20 20 
 	"github.com/docker/docker/daemon/internal/unshare"
21 
-	"github.com/docker/docker/pkg/fileutils"
22 21 
 	containertypes "github.com/moby/moby/api/types/container"
23 22 
 )
24 23
... ... 
@@ -104,7 +103,7 @@ func (daemon *Daemon) openContainerFS(ctr *container.Container) (_ *containerFSV
104 104 
 				if err != nil {
105 105 
 					return err
106 106 
 				}
107 
-				if err := fileutils.CreateIfNotExists(dest, stat.IsDir()); err != nil {
107 
+				if err := createIfNotExists(dest, stat.IsDir()); err != nil {
108 108 
 					return err
109 109 
 				}
110 110
... ... 
@@ -252,6 +251,27 @@ func (vw *containerFSView) Stat(ctx context.Context, path string) (*containertyp
252 252 
 	return stat, err
253 253 
 }
254 254
255 
+// createIfNotExists creates a file or a directory only if it does not already exist.
256 
+func createIfNotExists(dest string, isDir bool) error {
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+	if _, err := os.Stat(dest); err != nil {
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+		// FIXME(thaJeztah): this ignores any other error (which may include "dest" is of the wrong type, or permission errors).
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+		if os.IsNotExist(err) {
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+			if isDir {
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+				return os.MkdirAll(dest, 0o755)
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+			}
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+			if err := os.MkdirAll(filepath.Dir(dest), 0o755); err != nil {
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+				return err
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+			}
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+			f, err := os.OpenFile(dest, os.O_CREATE, 0o755)
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+			if err != nil {
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+				return err
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+			}
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+			_ = f.Close()
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+		}
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+	}
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+	return nil
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+}
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+
255 276 
 // makeMountRRO makes the mount recursively read-only.
256 277 
 func makeMountRRO(dest string) error {
257 278 
 	attr := &unix.MountAttr{
daemon/containerfs_linux_test.go
History View file @ ae0a3d6
258 279 
new file mode 100644
... ... 
@@ -0,0 +1,39 @@
0 
+package daemon
1 
+
2 
+import (
3 
+	"os"
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+	"path/filepath"
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+	"testing"
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+
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+	"gotest.tools/v3/assert"
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+)
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+
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+func TestCreateIfNotExists(t *testing.T) {
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+	t.Run("directory", func(t *testing.T) {
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+		toCreate := filepath.Join(t.TempDir(), "tocreate")
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+
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+		err := createIfNotExists(toCreate, true)
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+		assert.NilError(t, err)
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+
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+		fileinfo, err := os.Stat(toCreate)
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+		assert.NilError(t, err, "Did not create destination")
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+		assert.Assert(t, fileinfo.IsDir(), "Should have been a dir, seems it's not")
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+
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+		err = createIfNotExists(toCreate, true)
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+		assert.NilError(t, err, "Should not fail if already exists")
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+	})
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+	t.Run("file", func(t *testing.T) {
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+		toCreate := filepath.Join(t.TempDir(), "file/to/create")
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+
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+		err := createIfNotExists(toCreate, false)
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+		assert.NilError(t, err)
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+
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+		fileinfo, err := os.Stat(toCreate)
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+		assert.NilError(t, err, "Did not create destination")
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+
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+		assert.Assert(t, !fileinfo.IsDir(), "Should have been a file, but created a directory")
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+
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+		err = createIfNotExists(toCreate, true)
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+		assert.NilError(t, err, "Should not fail if already exists")
37 
+	})
38 
+}
pkg/fileutils/fileutils.go
History View file @ ae0a3d6
... ... 
@@ -27,23 +27,3 @@ func ReadSymlinkedDirectory(path string) (realPath string, _ error) {
27 27 
 	}
28 28 
 	return realPath, nil
29 29 
 }
30 
-
31 
-// CreateIfNotExists creates a file or a directory only if it does not already exist.
32 
-func CreateIfNotExists(path string, isDir bool) error {
33 
-	if _, err := os.Stat(path); err != nil {
34 
-		if os.IsNotExist(err) {
35 
-			if isDir {
36 
-				return os.MkdirAll(path, 0o755)
37 
-			}
38 
-			if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
39 
-				return err
40 
-			}
41 
-			f, err := os.OpenFile(path, os.O_CREATE, 0o755)
42 
-			if err != nil {
43 
-				return err
44 
-			}
45 
-			_ = f.Close()
46 
-		}
47 
-	}
48 
-	return nil
49 
-}
pkg/fileutils/fileutils_test.go
History View file @ ae0a3d6
... ... 
@@ -107,35 +107,3 @@ func TestReadSymlinkedDirectoryToFile(t *testing.T) {
107 107 
 		t.Errorf("failed to remove symlink: %s", err)
108 108 
 	}
109 109 
 }
110 
-
111 
-func TestCreateIfNotExistsDir(t *testing.T) {
112 
-	folderToCreate := filepath.Join(t.TempDir(), "tocreate")
113 
-
114 
-	if err := CreateIfNotExists(folderToCreate, true); err != nil {
115 
-		t.Fatal(err)
116 
-	}
117 
-	fileinfo, err := os.Stat(folderToCreate)
118 
-	if err != nil {
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-		t.Fatalf("Should have create a folder, got %v", err)
120 
-	}
121 
-
122 
-	if !fileinfo.IsDir() {
123 
-		t.Errorf("Should have been a dir, seems it's not")
124 
-	}
125 
-}
126 
-
127 
-func TestCreateIfNotExistsFile(t *testing.T) {
128 
-	fileToCreate := filepath.Join(t.TempDir(), "file/to/create")
129 
-
130 
-	if err := CreateIfNotExists(fileToCreate, false); err != nil {
131 
-		t.Error(err)
132 
-	}
133 
-	fileinfo, err := os.Stat(fileToCreate)
134 
-	if err != nil {
135 
-		t.Fatalf("Should have create a file, got %v", err)
136 
-	}
137 
-
138 
-	if fileinfo.IsDir() {
139 
-		t.Errorf("Should have been a file, seems it's not")
140 
-	}
141 
-}