| /* |
| * Copyright 2008-2009 Sun Microsystems, Inc. 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. Sun designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| * CA 95054 USA or visit www.sun.com if you need additional information or |
| * have any questions. |
| */ |
| |
| package sun.nio.fs; |
| |
| 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 { |
| UnixFileSystem fs = 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 |
| byte[] dir = path.asByteArray(); |
| for (UnixMountEntry entry: fs.getMountEntries()) { |
| if (Arrays.equals(dir, entry.dir())) |
| return entry; |
| } |
| |
| throw new IOException("Mount point not found in mtab"); |
| } |
| |
| // 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) { |
| try { |
| int fd = path.openForAttributeAccess(false); |
| try { |
| // fgetxattr returns size if called with size==0 |
| LinuxNativeDispatcher.fgetxattr(fd, "user.java".getBytes(), 0L, 0); |
| return true; |
| } catch (UnixException e) { |
| // attribute does not exist |
| if (e.errno() == UnixConstants.ENODATA) |
| return true; |
| } finally { |
| UnixNativeDispatcher.close(fd); |
| } |
| } catch (IOException ignore) { |
| // nothing we can do |
| } |
| return false; |
| } |
| |
| @Override |
| public boolean supportsFileAttributeView(String name) { |
| // support DosFileAttributeView and NamedAttributeView if extended |
| // attributes enabled |
| if (name.equals("dos") || name.equals("xattr")) { |
| // 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; |
| } |
| |
| return super.supportsFileAttributeView(name); |
| } |
| |
| @Override |
| boolean isLoopback() { |
| return false; |
| } |
| } |