| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.cassandra.utils; |
| |
| import java.util.Collections; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import com.sun.jna.LastErrorException; |
| import com.sun.jna.Native; |
| import com.sun.jna.Pointer; |
| |
| /** |
| * A {@code NativeLibraryWrapper} implementation for Linux. |
| * <p> |
| * When JNA is initialized, all methods that have the 'native' keyword |
| * will be attmpted to be linked against. As Java doesn't have the equivalent |
| * of a #ifdef, this means if a native method like posix_fadvise is defined in the |
| * class but not available on the target operating system (e.g. |
| * posix_fadvise is not availble on Darwin/Mac) this will cause the entire |
| * initial linking and initialization of JNA to fail. This means other |
| * native calls that are supported on that target operating system will be |
| * unavailable simply because of one native defined method not supported |
| * on the runtime operating system. |
| * @see org.apache.cassandra.utils.NativeLibraryWrapper |
| * @see NativeLibrary |
| */ |
| @Shared |
| public class NativeLibraryLinux implements NativeLibraryWrapper |
| { |
| private static boolean available; |
| |
| private static final Logger logger = LoggerFactory.getLogger(NativeLibraryLinux.class); |
| |
| static |
| { |
| try |
| { |
| Native.register(com.sun.jna.NativeLibrary.getInstance("c", Collections.emptyMap())); |
| available = true; |
| } |
| catch (NoClassDefFoundError e) |
| { |
| logger.warn("JNA not found. Native methods will be disabled."); |
| } |
| catch (UnsatisfiedLinkError e) |
| { |
| logger.error("Failed to link the C library against JNA. Native methods will be unavailable.", e); |
| } |
| catch (NoSuchMethodError e) |
| { |
| logger.warn("Obsolete version of JNA present; unable to register C library. Upgrade to JNA 3.2.7 or later"); |
| } |
| } |
| |
| private static native int mlockall(int flags) throws LastErrorException; |
| private static native int munlockall() throws LastErrorException; |
| private static native int fcntl(int fd, int command, long flags) throws LastErrorException; |
| private static native int posix_fadvise(int fd, long offset, int len, int flag) throws LastErrorException; |
| private static native int open(String path, int flags) throws LastErrorException; |
| private static native int fsync(int fd) throws LastErrorException; |
| private static native int close(int fd) throws LastErrorException; |
| private static native Pointer strerror(int errnum) throws LastErrorException; |
| private static native long getpid() throws LastErrorException; |
| |
| public int callMlockall(int flags) throws UnsatisfiedLinkError, RuntimeException |
| { |
| return mlockall(flags); |
| } |
| |
| public int callMunlockall() throws UnsatisfiedLinkError, RuntimeException |
| { |
| return munlockall(); |
| } |
| |
| public int callFcntl(int fd, int command, long flags) throws UnsatisfiedLinkError, RuntimeException |
| { |
| return fcntl(fd, command, flags); |
| } |
| |
| public int callPosixFadvise(int fd, long offset, int len, int flag) throws UnsatisfiedLinkError, RuntimeException |
| { |
| return posix_fadvise(fd, offset, len, flag); |
| } |
| |
| public int callOpen(String path, int flags) throws UnsatisfiedLinkError, RuntimeException |
| { |
| return open(path, flags); |
| } |
| |
| public int callFsync(int fd) throws UnsatisfiedLinkError, RuntimeException |
| { |
| return fsync(fd); |
| } |
| |
| public int callClose(int fd) throws UnsatisfiedLinkError, RuntimeException |
| { |
| return close(fd); |
| } |
| |
| public Pointer callStrerror(int errnum) throws UnsatisfiedLinkError, RuntimeException |
| { |
| return strerror(errnum); |
| } |
| |
| public long callGetpid() throws UnsatisfiedLinkError, RuntimeException |
| { |
| return getpid(); |
| } |
| |
| public boolean isAvailable() |
| { |
| return available; |
| } |
| } |