8276661: (fs) UserDefinedFileAttributeView no longer works with long …

…path (win)

Reviewed-by: alanb

src/java.base/windows/classes/sun/nio/fs/WindowsPath.java

@@ -174,38 +174,48 @@ String getPathForPermissionCheck() {
     // use this path for Win32 calls
     // This method will prefix long paths with \\?\ or \\?\UNC as required.
     String getPathForWin32Calls() throws WindowsException {
-        // short absolute paths can be used directly
-        if (isAbsolute() && path.length() <= MAX_PATH)
-            return path;
+        return getPathForWin32Calls(true);
+    }
+
+    String getPathWithPrefixForWin32Calls() throws WindowsException {
+        return getPathForWin32Calls(false);
+    }
 
-        // return cached values if available
-        WeakReference<String> ref = pathForWin32Calls;
-        String resolved = (ref != null) ? ref.get() : null;
-        if (resolved != null) {
-            // Win32 path already available
-            return resolved;
+    private String getPathForWin32Calls(boolean allowShortPath) throws WindowsException {
+        if (allowShortPath) {
+            // short absolute paths can be used directly
+            if (isAbsolute() && path.length() <= MAX_PATH)
+                return path;
+
+            // returned cached value if possible
+            WeakReference<String> ref = pathForWin32Calls;
+            String cached = (ref != null) ? ref.get() : null;
+            if (cached != null) {
+                // Win32 path already available
+                return cached;
+            }
         }
 
         // resolve against default directory
-        resolved = getAbsolutePath();
+        String resolved = getAbsolutePath();
 
         // Long paths need to have "." and ".." removed and be prefixed with
         // "\\?\". Note that it is okay to remove ".." even when it follows
         // a link - for example, it is okay for foo/link/../bar to be changed
         // to foo/bar. The reason is that Win32 APIs to access foo/link/../bar
         // will access foo/bar anyway (which differs to Unix systems)
-        if (resolved.length() > MAX_PATH) {
+        if (resolved.length() > MAX_PATH || !allowShortPath) {
             if (resolved.length() > MAX_LONG_PATH) {
                 throw new WindowsException("Cannot access file with path exceeding "
                     + MAX_LONG_PATH + " characters");
             }
-            resolved = addPrefixIfNeeded(GetFullPathName(resolved));
+            resolved = addPrefix(GetFullPathName(resolved));
         }
 
         // cache the resolved path (except drive relative paths as the working
         // directory on removal media devices can change during the lifetime
         // of the VM)
-        if (type != WindowsPathType.DRIVE_RELATIVE) {
+        if (allowShortPath && type != WindowsPathType.DRIVE_RELATIVE) {
             synchronized (this) {
                 pathForWin32Calls = new WeakReference<String>(resolved);
             }
@@ -279,14 +289,20 @@ private static boolean isSameDrive(String root1, String root2) {
                Character.toUpperCase(root2.charAt(0));
     }
 
+    // Add long path prefix to path
+    static String addPrefix(String path) {
+        if (path.startsWith("\\\\")) {
+            path = "\\\\?\\UNC" + path.substring(1, path.length());
+        } else {
+            path = "\\\\?\\" + path;
+        }
+        return path;
+    }
+
     // Add long path prefix to path if required
     static String addPrefixIfNeeded(String path) {
         if (path.length() > MAX_PATH) {
-            if (path.startsWith("\\\\")) {
-                path = "\\\\?\\UNC" + path.substring(1, path.length());
-            } else {
-                path = "\\\\?\\" + path;
-            }
+            return addPrefix(path);
         }
         return path;
     }

src/java.base/windows/classes/sun/nio/fs/WindowsUserDefinedFileAttributeView.java

@@ -61,9 +61,7 @@ private String join(WindowsPath file, String name) throws WindowsException {
             throw new IllegalArgumentException("'name' has a root component");
         if (namePath.getParent() != null)
             throw new IllegalArgumentException("'name' has more than one element");
-        String path = join(file.getPathForWin32Calls(), name);
-        WindowsPath wp = WindowsPath.createFromNormalizedPath(wfs, path);
-        return wp.getPathForWin32Calls();
+        return join(file.getPathWithPrefixForWin32Calls(), name);
     }
 
     private final WindowsPath file;

test/jdk/java/nio/file/attribute/UserDefinedFileAttributeView/Basic.java

@@ -242,7 +242,7 @@ public void run() throws IOException {
 
             // We need to run up to MAX_PATH for directories,
             // but not quite go over it.
-            int MAX_PATH = 247;
+            int MAX_PATH = 250;
             int requiredLen = MAX_PATH - len - 2;
 
             // Create a really long directory name.
@@ -252,11 +252,15 @@ public void run() throws IOException {
             Files.createDirectory(longPath);
 
             try {
-                // Try to set absolute path as extended attribute; expect IAE
+                System.out.println("Testing " + longPath);
+
+                // Try to set absolute path as extended attribute;
+                // expect IAE
                 tryCatch(IllegalArgumentException.class, new Task() {
                     public void run() throws IOException {
                         setEA(longPath, "user:C:\\");
-                    }});
+                    }
+                });
 
                 // Try to set an extended attribute on it.
                 setEA(longPath, "user:short");