fix: error out when the source and destination might be subdirectories of each other (#5173)

Author: jiuker

cmd/client-url.go

@@ -267,3 +267,37 @@ func guessURLContentType(urlStr string) string {
 	contentType := mimedb.TypeByExtension(filepath.Ext(url.Path))
 	return contentType
 }
+
+// urlParts - split URL into parts.
+func urlParts(urlStr string) []string {
+	// Convert '/' on windows to filepath.Separator.
+	urlStr = filepath.FromSlash(urlStr)
+
+	if runtime.GOOS == "windows" {
+		// Remove '/' prefix before alias if any to support '\\home' alias
+		// style under Windows
+		urlStr = strings.TrimPrefix(urlStr, string(filepath.Separator))
+	}
+
+	// Remove everything after alias (i.e. after '/').
+	return strings.Split(urlStr, string(filepath.Separator))
+}
+
+// isURLPrefix - check if source and destination be subdirectories of each other
+func isURLPrefix(src string, dest string) bool {
+	srcURLParts := urlParts(src)
+	dstURLParts := urlParts(dest)
+	minIndex := min(len(srcURLParts), len(dstURLParts))
+	isPrefix := true
+	for i := 0; i < minIndex; i++ {
+		// if one of the URLs ends with '/' and other does not
+		if (i == minIndex-1) && (dstURLParts[i] == "" || srcURLParts[i] == "" || dstURLParts[i] == "*" || srcURLParts[i] == "*") {
+			continue
+		}
+		if srcURLParts[i] != dstURLParts[i] {
+			isPrefix = false
+			break
+		}
+	}
+	return isPrefix
+}

cmd/client-url_test.go

@@ -17,7 +17,11 @@
 
 package cmd
 
-import checkv1 "gopkg.in/check.v1"
+import (
+	"testing"
+
+	checkv1 "gopkg.in/check.v1"
+)
 
 // TestURL - tests url parsing and fields.
 func (s *TestSuite) TestURL(c *checkv1.C) {
@@ -52,3 +56,33 @@ func (s *TestSuite) TestURLJoinPath(c *checkv1.C) {
 	url = urlJoinPath(url1, url2)
 	c.Assert(url, checkv1.Equals, "http://s3.mycompany.io/dev/mybucket/bin/")
 }
+
+func Test_isURLPrefix(t *testing.T) {
+	type args struct {
+		src  string
+		dest string
+	}
+	tests := []struct {
+		name string
+		args args
+		want bool
+	}{
+		{"test1", args{"s3/test", "s3/test/test"}, true},
+		{"test2", args{"s3/test/", "s3/test/test"}, true},
+		{"test3", args{"s3/test/test", "s3/test/"}, true},
+		{"test4", args{"s3/test/test", "s3/test/test.123"}, false},
+		{"test5", args{"s3/test/", "s3/test/test/test/test"}, true},
+		{"test6", args{"s3/test/*", "s3/test/test/"}, true},
+		{"test7", args{"s3/test/*", "s3/test1/test/"}, false},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := isURLPrefix(tt.args.src, tt.args.dest); got != tt.want {
+				t.Errorf("isURLPrefix() = %v, want %v", got, tt.want)
+			}
+			if got := isURLPrefix(tt.args.dest, tt.args.src); got != tt.want {
+				t.Errorf("isURLPrefix() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

cmd/mv-main.go

@@ -210,8 +210,9 @@ func mainMove(cliCtx *cli.Context) error {
 		args := cliCtx.Args()
 		srcURL := args.Get(0)
 		dstURL := args.Get(1)
-		if srcURL == dstURL {
-			fatalIf(errDummy().Trace(), fmt.Sprintf("Source and destination urls cannot be the same: %v.", srcURL))
+		if isURLPrefix(srcURL, dstURL) {
+			fatalIf(errDummy().Trace(), fmt.Sprintf("The source %v and destination %v cannot be subdirectories of each other", srcURL, dstURL))
+			return nil
 		}
 	}