--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.base/linux/classes/sun/nio/fs/LinuxFileStore.java Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,161 @@
+/*
+ * Copyright (c) 2008, 2015, 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. Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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.
+ */
+
+package sun.nio.fs;
+
+import java.nio.file.attribute.*;
+import java.util.*;
+import java.io.IOException;
+
+/**
+ * Linux implementation of FileStore
+ */
+
+class LinuxFileStore
+ extends UnixFileStore
+{
+ // used when checking if extended attributes are enabled or not
+ private volatile boolean xattrChecked;
+ private volatile boolean xattrEnabled;
+
+ LinuxFileStore(UnixPath file) throws IOException {
+ super(file);
+ }
+
+ LinuxFileStore(UnixFileSystem fs, UnixMountEntry entry) throws IOException {
+ super(fs, entry);
+ }
+
+ /**
+ * Finds, and returns, the mount entry for the file system where the file
+ * resides.
+ */
+ @Override
+ UnixMountEntry findMountEntry() throws IOException {
+ LinuxFileSystem fs = (LinuxFileSystem)file().getFileSystem();
+
+ // step 1: get realpath
+ UnixPath path = null;
+ try {
+ byte[] rp = UnixNativeDispatcher.realpath(file());
+ path = new UnixPath(fs, rp);
+ } catch (UnixException x) {
+ x.rethrowAsIOException(file());
+ }
+
+ // step 2: find mount point
+ UnixPath parent = path.getParent();
+ while (parent != null) {
+ UnixFileAttributes attrs = null;
+ try {
+ attrs = UnixFileAttributes.get(parent, true);
+ } catch (UnixException x) {
+ x.rethrowAsIOException(parent);
+ }
+ if (attrs.dev() != dev())
+ break;
+ path = parent;
+ parent = parent.getParent();
+ }
+
+ // step 3: lookup mounted file systems (use /proc/mounts to ensure we
+ // find the file system even when not in /etc/mtab)
+ byte[] dir = path.asByteArray();
+ for (UnixMountEntry entry: fs.getMountEntries("/proc/mounts")) {
+ if (Arrays.equals(dir, entry.dir()))
+ return entry;
+ }
+
+ throw new IOException("Mount point not found");
+ }
+
+ // returns true if extended attributes enabled on file system where given
+ // file resides, returns false if disabled or unable to determine.
+ private boolean isExtendedAttributesEnabled(UnixPath path) {
+ int fd = -1;
+ try {
+ fd = path.openForAttributeAccess(false);
+
+ // fgetxattr returns size if called with size==0
+ byte[] name = Util.toBytes("user.java");
+ LinuxNativeDispatcher.fgetxattr(fd, name, 0L, 0);
+ return true;
+ } catch (UnixException e) {
+ // attribute does not exist
+ if (e.errno() == UnixConstants.ENODATA)
+ return true;
+ } finally {
+ UnixNativeDispatcher.close(fd);
+ }
+ return false;
+ }
+
+ @Override
+ public boolean supportsFileAttributeView(Class<? extends FileAttributeView> type) {
+ // support DosFileAttributeView and UserDefinedAttributeView if extended
+ // attributes enabled
+ if (type == DosFileAttributeView.class ||
+ type == UserDefinedFileAttributeView.class)
+ {
+ // lookup fstypes.properties
+ FeatureStatus status = checkIfFeaturePresent("user_xattr");
+ if (status == FeatureStatus.PRESENT)
+ return true;
+ if (status == FeatureStatus.NOT_PRESENT)
+ return false;
+
+ // if file system is mounted with user_xattr option then assume
+ // extended attributes are enabled
+ if ((entry().hasOption("user_xattr")))
+ return true;
+
+ // user_xattr option not present but we special-case ext3/4 as we
+ // know that extended attributes are not enabled by default.
+ if (entry().fstype().equals("ext3") || entry().fstype().equals("ext4"))
+ return false;
+
+ // not ext3/4 so probe mount point
+ if (!xattrChecked) {
+ UnixPath dir = new UnixPath(file().getFileSystem(), entry().dir());
+ xattrEnabled = isExtendedAttributesEnabled(dir);
+ xattrChecked = true;
+ }
+ return xattrEnabled;
+ }
+ // POSIX attributes not supported on FAT
+ if (type == PosixFileAttributeView.class && entry().fstype().equals("vfat"))
+ return false;
+ return super.supportsFileAttributeView(type);
+ }
+
+ @Override
+ public boolean supportsFileAttributeView(String name) {
+ if (name.equals("dos"))
+ return supportsFileAttributeView(DosFileAttributeView.class);
+ if (name.equals("user"))
+ return supportsFileAttributeView(UserDefinedFileAttributeView.class);
+ return super.supportsFileAttributeView(name);
+ }
+}