8287843: File::getCanonicalFile doesn't work for \\?\C:\ style paths DOS device paths

Reviewed-by: alanb

src/java.base/windows/classes/java/io/WinNTFileSystem.java

@@ -41,6 +41,8 @@ import sun.security.action.GetPropertyAction;
  */
 final class WinNTFileSystem extends FileSystem {
 
+    private static final String LONG_PATH_PREFIX = "\\\\?\\";
+
     private final char slash;
     private final char altSlash;
     private final char semicolon;
@@ -60,6 +62,25 @@ final class WinNTFileSystem extends FileSystem {
         }
     }
 
+    // Strip a long path or UNC prefix and return the result.
+    // If there is no such prefix, return the parameter passed in.
+    private static String stripLongOrUNCPrefix(String path) {
+        // if a prefix is present, remove it
+        if (path.startsWith(LONG_PATH_PREFIX)) {
+            if (path.startsWith("UNC\\", 4)) {
+                path = "\\\\" + path.substring(8);
+            } else {
+                path = path.substring(4);
+                // if only "UNC" remains, a trailing "\\" was likely removed
+                if (path.equals("UNC")) {
+                    path = "\\\\";
+                }
+            }
+        }
+
+        return path;
+    }
+
     WinNTFileSystem() {
         Properties props = GetPropertyAction.privilegedGetProperties();
         slash = props.getProperty("file.separator").charAt(0);
@@ -98,6 +119,7 @@ final class WinNTFileSystem extends FileSystem {
        This way we iterate through the whole pathname string only once. */
     @Override
     public String normalize(String path) {
+        path = stripLongOrUNCPrefix(path);
         int n = path.length();
         char slash = this.slash;
         char altSlash = this.altSlash;
@@ -223,6 +245,8 @@ final class WinNTFileSystem extends FileSystem {
 
     @Override
     public int prefixLength(String path) {
+        assert !path.startsWith(LONG_PATH_PREFIX);
+
         char slash = this.slash;
         int n = path.length();
         if (n == 0) return 0;
@@ -242,6 +266,8 @@ final class WinNTFileSystem extends FileSystem {
 
     @Override
     public String resolve(String parent, String child) {
+        assert !child.startsWith(LONG_PATH_PREFIX);
+
         int pn = parent.length();
         if (pn == 0) return child;
         int cn = child.length();
@@ -320,6 +346,9 @@ final class WinNTFileSystem extends FileSystem {
 
     @Override
     public boolean isAbsolute(File f) {
+        String path = f.getPath();
+        assert !path.startsWith(LONG_PATH_PREFIX);
+
         int pl = f.getPrefixLength();
         return (((pl == 2) && (f.getPath().charAt(0) == slash))
                 || (pl == 3));
@@ -358,6 +387,8 @@ final class WinNTFileSystem extends FileSystem {
     @Override
     public String resolve(File f) {
         String path = f.getPath();
+        assert !path.startsWith(LONG_PATH_PREFIX);
+
         int pl = f.getPrefixLength();
         if ((pl == 2) && (path.charAt(0) == slash))
             return path;                        /* UNC */
@@ -440,6 +471,8 @@ final class WinNTFileSystem extends FileSystem {
 
     @Override
     public String canonicalize(String path) throws IOException {
+        assert !path.startsWith(LONG_PATH_PREFIX);
+
         // If path is a drive letter only then skip canonicalization
         int len = path.length();
         if ((len == 2) &&

test/jdk/java/io/File/GetAbsolutePath.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2001, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -22,74 +22,89 @@
  */
 
 /* @test
-   @bug 4131169 4109131
+ * @bug 4131169 4109131 8287843
-   @summary Basic test for getAbsolutePath method
+ * @summary Basic test for getAbsolutePath method
+ * @run junit GetAbsolutePath
  */
 
-import java.io.*;
+import java.io.File;
+import java.io.IOException;
+import java.util.stream.Stream;
 
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.condition.EnabledOnOs;
+import org.junit.jupiter.api.condition.OS;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+import static org.junit.jupiter.api.Assertions.*;
 
 public class GetAbsolutePath {
 
-    private static boolean ignoreCase = false;
+    private static final String USER_DIR = System.getProperty("user.dir");
 
-    private static void ck(String path, String ans) throws Exception {
+    private static char driveLetter() {
-        File f = new File(path);
+        assert System.getProperty("os.name").startsWith("Windows");
-        String p = f.getAbsolutePath();
+
-        if ((ignoreCase && p.equalsIgnoreCase(ans)) || p.equals(ans))
+        if ((USER_DIR.length() > 2) && (USER_DIR.charAt(1) == ':')
-            System.err.println(path + " ==> " + p);
+            && (USER_DIR.charAt(2) == '\\'))
-        else
+            return USER_DIR.charAt(0);
-            throw new Exception(path + ": expected " + ans + ", got " + p);
+
+        throw new RuntimeException("Current directory has no drive");
     }
 
-    private static void testWin32() throws Exception {
+    private static Stream<Arguments> windowsSource() {
-        String wd = System.getProperty("user.dir");
+        char drive = driveLetter();
-        char d;
+        return Stream.of(Arguments.of("/foo/bar", drive + ":\\foo\\bar"),
-        if ((wd.length() > 2) && (wd.charAt(1) == ':')
+                         Arguments.of("\\foo\\bar", drive + ":\\foo\\bar"),
-            && (wd.charAt(2) == '\\'))
+                         Arguments.of("c:\\foo\\bar", "c:\\foo\\bar"),
-            d = wd.charAt(0);
+                         Arguments.of("c:/foo/bar", "c:\\foo\\bar"),
-        else
+                         Arguments.of("\\\\foo\\bar", "\\\\foo\\bar"),
-            throw new Exception("Current directory has no drive");
+                         Arguments.of("", USER_DIR), // empty path
-        ck("/foo/bar", d + ":\\foo\\bar");
+                         Arguments.of("\\\\?\\foo", USER_DIR + "\\foo"),
-        ck("\\foo\\bar", d + ":\\foo\\bar");
+                         Arguments.of("\\\\?\\C:\\Users\\x", "C:\\Users\\x"),
-        ck("c:\\foo\\bar", "c:\\foo\\bar");
+                         Arguments.of("\\\\?\\" + drive + ":", USER_DIR),
-        ck("c:/foo/bar", "c:\\foo\\bar");
+                         Arguments.of("\\\\?\\" + drive + ":bar", USER_DIR + "\\bar"));
-        ck("\\\\foo\\bar", "\\\\foo\\bar");
+    }
 
-        /* Tricky directory-relative case */
+    @EnabledOnOs(OS.WINDOWS)
-        d = Character.toLowerCase(d);
+    @ParameterizedTest
+    @MethodSource("windowsSource")
+    public void windows(String path, String absolute) throws IOException {
+        File file = new File(path);
+        assertEquals(0, absolute.compareToIgnoreCase(file.getAbsolutePath()));
+    }
+
+    @EnabledOnOs(OS.WINDOWS)
+    @Test
+    public void windowsDriveRelative() throws IOException {
+        // Tricky directory-relative case
+        char d = Character.toLowerCase(driveLetter());
         char z = 0;
         if (d != 'c') z = 'c';
         else if (d != 'd') z = 'd';
         if (z != 0) {
             File f = new File(z + ":.");
             if (f.exists()) {
-                String zwd = f.getCanonicalPath();
+                String zUSER_DIR = f.getCanonicalPath();
-                ck(z + ":foo", zwd + "\\foo");
+                assertEquals(z + ":foo", zUSER_DIR + "\\foo");
             }
         }
-
-        /* Empty path */
-        ck("", wd);
     }
 
-    private static void testUnix() throws Exception {
+    private static Stream<Arguments> unixSource() {
-        String wd = System.getProperty("user.dir");
+        return Stream.of(Arguments.of("foo", USER_DIR + "/foo"),
-        ck("foo", wd + "/foo");
+                         Arguments.of("foo/bar", USER_DIR + "/foo/bar"),
-        ck("foo/bar", wd + "/foo/bar");
+                         Arguments.of("/foo", "/foo"),
-        ck("/foo", "/foo");
+                         Arguments.of("/foo/bar", "/foo/bar"),
-        ck("/foo/bar", "/foo/bar");
+                         Arguments.of("", USER_DIR));
-
-        /* Empty path */
-        ck("", wd);
     }
 
-    public static void main(String[] args) throws Exception {
+    @EnabledOnOs({OS.LINUX, OS.MAC})
-        if (File.separatorChar == '\\') {
+    @ParameterizedTest
-            ignoreCase = true;
+    @MethodSource("unixSource")
-            testWin32();
+    public void unix(String path, String absolute) throws IOException {
-        }
+        assertEquals(absolute, new File(path).getAbsolutePath());
-        if (File.separatorChar == '/') testUnix();
     }
-
 }

test/jdk/java/io/File/GetCanonicalPath.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -22,21 +22,81 @@
  */
 
 /* @test
-   @bug 4899022
+ * @bug 4899022
-   @summary Look for erroneous representation of drive letter
+ * @requires (os.family == "windows")
+ * @summary Look for erroneous representation of drive letter
+ * @run junit GetCanonicalPath
  */
 
-import java.io.*;
+import java.io.File;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Stream;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+import org.junit.jupiter.params.provider.ValueSource;
+
+import static org.junit.jupiter.api.Assertions.*;
 
 public class GetCanonicalPath {
-    public static void main(String[] args) throws Exception {
+    private static Stream<Arguments> pathProvider() {
-        if (File.separatorChar == '\\') {
+        List<Arguments> list = new ArrayList<Arguments>();
-            testDriveLetter();
+
-        }
+        File dir = new File(System.getProperty("user.dir", "."));
+        char drive = dir.getPath().charAt(0);
+
+        String pathname = drive + ":\\";
+        list.add(Arguments.of(pathname, pathname));
+
+        list.add(Arguments.of(drive + ":", dir.toString()));
+
+        String name = "foo";
+        pathname = "\\\\?\\" + name;
+        list.add(Arguments.of(pathname, new File(dir, name).toString()));
+        pathname = "\\\\?\\" + drive + ":" + name;
+        list.add(Arguments.of(pathname, new File(dir, name).toString()));
+
+        pathname = "foo\\bar\\gus";
+        list.add(Arguments.of(pathname, new File(dir, pathname).toString()));
+
+        pathname = drive + ":\\foo\\bar\\gus";
+        list.add(Arguments.of(pathname, pathname));
+
+        pathname = "\\\\server\\share\\foo\\bar\\gus";
+        list.add(Arguments.of(pathname, pathname));
+
+        pathname = "\\\\localhost\\" + drive + "$\\Users\\file.dat";
+        list.add(Arguments.of(pathname, pathname));
+
+        list.add(Arguments.of("\\\\?\\" + drive + ":\\Users\\file.dat",
+                              drive + ":\\Users\\file.dat"));
+        list.add(Arguments.of("\\\\?\\UNC\\localhost\\" + drive + "$\\Users\\file.dat",
+                              "\\\\localhost\\" + drive + "$\\Users\\file.dat"));
+
+        return list.stream();
     }
-    private static void testDriveLetter() throws Exception {
+
+    @ParameterizedTest
+    @ValueSource(strings = {"\\\\?", "\\\\?\\UNC", "\\\\?\\UNC\\"})
+    void badPaths(String pathname) {
+        assertThrows(IOException.class, () -> new File(pathname).getCanonicalPath());
+    }
+
+    @ParameterizedTest
+    @MethodSource("pathProvider")
+    void goodPaths(String pathname, String expected) throws IOException {
+        File file = new File(pathname);
+        String canonicalPath = file.getCanonicalPath();
+        assertEquals(expected, canonicalPath);
+    }
+
+    @Test
+    void driveLetter() throws IOException {
         String path = new File("c:/").getCanonicalPath();
-        if (path.length() > 3)
+        assertFalse(path.length() > 3, "Drive letter incorrectly represented");
-            throw new RuntimeException("Drive letter incorrectly represented");
     }
 }

test/jdk/java/io/File/IsAbsolute.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 1998, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -22,42 +22,46 @@
  */
 
 /* @test
-   @bug 4022397
+ * @bug 4022397 8287843
-   @summary General test for isAbsolute
+ * @summary General test for isAbsolute
+ * @run junit IsAbsolute
  */
 
-import java.io.*;
+import java.io.File;
+import java.io.IOException;
 
+import org.junit.jupiter.api.condition.EnabledOnOs;
+import org.junit.jupiter.api.condition.OS;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+import static org.junit.jupiter.api.Assertions.*;
 
 public class IsAbsolute {
-
+    @EnabledOnOs(OS.WINDOWS)
-    private static void ck(String path, boolean ans) throws Exception {
+    @ParameterizedTest
-        File f = new File(path);
+    @ValueSource(strings = {"c:\\foo\\bar", "c:/foo/bar", "\\\\foo\\bar"})
-        boolean x = f.isAbsolute();
+    public void windowsAbsolute(String path) throws IOException {
-        if (x != ans)
+        assertTrue(new File(path).isAbsolute());
-            throw new Exception(path + ": expected " + ans + ", got " + x);
-        System.err.println(path + " ==> " + x);
     }
 
-    private static void testWin32() throws Exception {
+    @EnabledOnOs(OS.WINDOWS)
-        ck("/foo/bar", false);
+    @ParameterizedTest
-        ck("\\foo\\bar", false);
+    @ValueSource(strings = {"/foo/bar", "\\foo\\bar", "c:foo\\bar"})
-        ck("c:\\foo\\bar", true);
+    public void windowsNotAbsolute(String path) throws IOException {
-        ck("c:/foo/bar", true);
+        assertFalse(new File(path).isAbsolute());
-        ck("c:foo\\bar", false);
-        ck("\\\\foo\\bar", true);
     }
 
-    private static void testUnix() throws Exception {
+    @EnabledOnOs({OS.LINUX, OS.MAC})
-        ck("foo", false);
+    @ParameterizedTest
-        ck("foo/bar", false);
+    @ValueSource(strings = {"/foo", "/foo/bar"})
-        ck("/foo", true);
+    public void unixAbsolute(String path) throws IOException {
-        ck("/foo/bar", true);
+        assertTrue(new File(path).isAbsolute());
     }
 
-    public static void main(String[] args) throws Exception {
+    @EnabledOnOs({OS.LINUX, OS.MAC})
-        if (File.separatorChar == '\\') testWin32();
+    @ParameterizedTest
-        if (File.separatorChar == '/') testUnix();
+    @ValueSource(strings = {"foo", "foo/bar"})
+    public void unixNotAbsolute(String path) throws IOException {
+        assertFalse(new File(path).isAbsolute());
     }
-
 }

test/jdk/java/io/File/WindowsPrefixes.java

@@ -0,0 +1,97 @@
+/*
+ * Copyright (c) 1998, 2023, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/* @test
+ * @bug 8287843
+ * @summary Basic test for Windows path prefixes
+ * @requires (os.family == "windows")
+ * @run junit WindowsPrefixes
+ */
+
+import java.io.File;
+import java.io.IOException;
+import java.util.stream.Stream;
+
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.condition.EnabledOnOs;
+import org.junit.jupiter.api.condition.OS;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+import static org.junit.jupiter.api.Assertions.*;
+
+public class WindowsPrefixes {
+
+    private static Stream<Arguments> paths() {
+        return Stream.of(Arguments.of(""),
+                         Arguments.of("C:\\"),
+                         Arguments.of("C:"),
+                         Arguments.of("\\foo"),
+                         Arguments.of("foo"),
+                         Arguments.of("foo\\bar"),
+                         Arguments.of("C:\\foo"),
+                         Arguments.of("C:foo"),
+                         Arguments.of("C:\\foo\\bar"));
+    }
+
+    @ParameterizedTest
+    @MethodSource("paths")
+    public void getAbsolutePath(String path) throws IOException {
+        File file = new File(path);
+        File that = new File("\\\\?\\" + path);
+        assertEquals(file.getAbsolutePath(), that.getAbsolutePath());
+    }
+
+    @ParameterizedTest
+    @MethodSource("paths")
+    public void getCanonicalPath(String path) throws IOException {
+        File file = new File(path);
+        File that = new File("\\\\?\\" + path);
+        assertEquals(file.getCanonicalPath(), that.getCanonicalPath());
+    }
+
+    @ParameterizedTest
+    @MethodSource("paths")
+    public void getName(String path) throws IOException {
+        File file = new File(path);
+        File that = new File("\\\\?\\" + path);
+        assertEquals(file.getName(), that.getName());
+    }
+
+    @ParameterizedTest
+    @MethodSource("paths")
+    public void getParent(String path) throws IOException {
+        File file = new File(path);
+        File that = new File("\\\\?\\" + path);
+        assertEquals(file.getParent(), that.getParent());
+    }
+
+    @ParameterizedTest
+    @MethodSource("paths")
+    public void isAbsolute(String path) throws IOException {
+        File file = new File(path);
+        File that = new File("\\\\?\\" + path);
+        assertEquals(file.isAbsolute(), that.isAbsolute());
+    }
+}