fsutil: Explicit parent directory creation (#76)

canonical · Aug 29, 2023 · f235273 · f235273
1 parent 5e8cdac
commit f235273
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Showing 5 changed files with 45 additions and 35 deletions.
diff --git a/internal/deb/extract.go b/internal/deb/extract.go
@@ -187,8 +187,9 @@ func extractData(dataReader io.Reader, options *ExtractOptions) error {
 				// the metadata, since the extracted content itself will also create
 				// any missing directories unaccounted for in the options.
 				err := fsutil.Create(&fsutil.CreateOptions{
-					Path: filepath.Join(options.TargetDir, sourcePath),
-					Mode: tarHeader.FileInfo().Mode(),
+					Path:        filepath.Join(options.TargetDir, sourcePath),
+					Mode:        tarHeader.FileInfo().Mode(),
+					MakeParents: true,
 				})
 				if err != nil {
 					return err
@@ -227,10 +228,11 @@ func extractData(dataReader io.Reader, options *ExtractOptions) error {
 				tarHeader.Mode = int64(extractInfo.Mode)
 			}
 			err := fsutil.Create(&fsutil.CreateOptions{
-				Path: targetPath,
-				Mode: tarHeader.FileInfo().Mode(),
-				Data: pathReader,
-				Link: tarHeader.Linkname,
+				Path:        targetPath,
+				Mode:        tarHeader.FileInfo().Mode(),
+				Data:        pathReader,
+				Link:        tarHeader.Linkname,
+				MakeParents: true,
 			})
 			if err != nil {
 				return err

diff --git a/internal/fsutil/create.go b/internal/fsutil/create.go
@@ -13,10 +13,19 @@ type CreateOptions struct {
 	Mode fs.FileMode
 	Data io.Reader
 	Link string
+	// If MakeParents is true, missing parent directories of Path are
+	// created with permissions 0755.
+	MakeParents bool
 }
 
+// Creates a filesystem entry according to the provided options.
 func Create(o *CreateOptions) error {
 	var err error
+	if o.MakeParents {
+		if err := os.MkdirAll(filepath.Dir(o.Path), 0755); err != nil {
+			return err
+		}
+	}
 	switch o.Mode & fs.ModeType {
 	case 0:
 		err = createFile(o)
@@ -32,11 +41,7 @@ func Create(o *CreateOptions) error {
 
 func createDir(o *CreateOptions) error {
 	debugf("Creating directory: %s (mode %#o)", o.Path, o.Mode)
-	err := os.MkdirAll(filepath.Dir(o.Path), 0755)
-	if err != nil {
-		return err
-	}
-	err = os.Mkdir(o.Path, o.Mode)
+	err := os.Mkdir(o.Path, o.Mode)
 	if os.IsExist(err) {
 		err = os.Chmod(o.Path, o.Mode)
 	}
@@ -45,10 +50,6 @@ func createDir(o *CreateOptions) error {
 
 func createFile(o *CreateOptions) error {
 	debugf("Writing file: %s (mode %#o)", o.Path, o.Mode)
-	err := os.MkdirAll(filepath.Dir(o.Path), 0755)
-	if err != nil && !os.IsExist(err) {
-		return err
-	}
 	file, err := os.OpenFile(o.Path, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, o.Mode)
 	if err != nil {
 		return err
@@ -63,10 +64,6 @@ func createFile(o *CreateOptions) error {
 
 func createSymlink(o *CreateOptions) error {
 	debugf("Creating symlink: %s => %s", o.Path, o.Link)
-	err := os.MkdirAll(filepath.Dir(o.Path), 0755)
-	if err != nil && !os.IsExist(err) {
-		return err
-	}
 	fileinfo, err := os.Lstat(o.Path)
 	if err == nil {
 		if (fileinfo.Mode() & os.ModeSymlink) != 0 {

diff --git a/internal/fsutil/create_test.go b/internal/fsutil/create_test.go
@@ -20,28 +20,31 @@ type createTest struct {
 
 var createTests = []createTest{{
 	options: fsutil.CreateOptions{
-		Path: "foo/bar",
-		Data: bytes.NewBufferString("data1"),
-		Mode: 0444,
+		Path:        "foo/bar",
+		Data:        bytes.NewBufferString("data1"),
+		Mode:        0444,
+		MakeParents: true,
 	},
 	result: map[string]string{
 		"/foo/":    "dir 0755",
 		"/foo/bar": "file 0444 5b41362b",
 	},
 }, {
 	options: fsutil.CreateOptions{
-		Path: "foo/bar",
-		Link: "../baz",
-		Mode: fs.ModeSymlink,
+		Path:        "foo/bar",
+		Link:        "../baz",
+		Mode:        fs.ModeSymlink,
+		MakeParents: true,
 	},
 	result: map[string]string{
 		"/foo/":    "dir 0755",
 		"/foo/bar": "symlink ../baz",
 	},
 }, {
 	options: fsutil.CreateOptions{
-		Path: "foo/bar",
-		Mode: fs.ModeDir | 0444,
+		Path:        "foo/bar",
+		Mode:        fs.ModeDir | 0444,
+		MakeParents: true,
 	},
 	result: map[string]string{
 		"/foo/":     "dir 0755",
@@ -55,6 +58,12 @@ var createTests = []createTest{{
 	result: map[string]string{
 		"/tmp/":     "dir 01775",
 	},
+}, {
+	options: fsutil.CreateOptions{
+		Path: "foo/bar",
+		Mode: fs.ModeDir | 0775,
+	},
+	error: `.*: no such file or directory`,
 }}
 
 func (s *S) TestCreate(c *C) {

diff --git a/internal/setup/fetch.go b/internal/setup/fetch.go
@@ -139,10 +139,11 @@ func extractTar(dataReader io.Reader, targetDir string) error {
 		//debugf("Extracting header: %#v", tarHeader)
 
 		err = fsutil.Create(&fsutil.CreateOptions{
-			Path: filepath.Join(targetDir, sourcePath),
-			Mode: tarHeader.FileInfo().Mode(),
-			Data: tarReader,
-			Link: tarHeader.Linkname,
+			Path:        filepath.Join(targetDir, sourcePath),
+			Mode:        tarHeader.FileInfo().Mode(),
+			Data:        tarReader,
+			Link:        tarHeader.Linkname,
+			MakeParents: true,
 		})
 		if err != nil {
 			return err

diff --git a/internal/slicer/slicer.go b/internal/slicer/slicer.go
@@ -212,10 +212,11 @@ func Run(options *RunOptions) error {
 			}
 
 			err := fsutil.Create(&fsutil.CreateOptions{
-				Path: targetPath,
-				Mode: tarHeader.FileInfo().Mode(),
-				Data: fileContent,
-				Link: linkTarget,
+				Path:        targetPath,
+				Mode:        tarHeader.FileInfo().Mode(),
+				Data:        fileContent,
+				Link:        linkTarget,
+				MakeParents: true,
 			})
 			if err != nil {
 				return err