| /** |
| * 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.sqoop.io; |
| |
| import java.io.File; |
| import java.io.IOException; |
| |
| import org.apache.hadoop.util.Shell; |
| import org.apache.log4j.Logger; |
| |
| /** |
| * A named FIFO channel. |
| */ |
| public class NamedFifo { |
| |
| private static final Logger LOG = Logger.getLogger(NamedFifo.class); |
| |
| private File fifoFile; |
| |
| /** Create a named FIFO object at the local fs path given by 'pathname'. */ |
| public NamedFifo(String pathname) { |
| this.fifoFile = new File(pathname); |
| } |
| |
| /** Create a named FIFO object at the local fs path given by the 'fifo' File |
| * object. */ |
| public NamedFifo(File fifo) { |
| this.fifoFile = fifo; |
| } |
| |
| /** |
| * Return the File object representing the FIFO. |
| */ |
| public File getFile() { |
| return this.fifoFile; |
| } |
| |
| /** |
| * Create a named FIFO object. |
| * The pipe will be created with permissions 0600. |
| * @throws IOException on failure. |
| */ |
| public void create() throws IOException { |
| create(0600); |
| } |
| |
| /** |
| * Create a named FIFO object with the specified fs permissions. |
| * This depends on the 'mknod' or 'mkfifo' (Mac OS X) system utility |
| * existing. (for example, provided by Linux coreutils). This object |
| * will be deleted when the process exits. |
| * @throws IOException on failure. |
| */ |
| public void create(int permissions) throws IOException { |
| String filename = fifoFile.toString(); |
| |
| // Format permissions as a mode string in base 8. |
| String modeStr = Integer.toString(permissions, 8); |
| |
| // Create the FIFO itself. |
| try { |
| String output = Shell.execCommand("mknod", "--mode=0" + modeStr, |
| filename, "p"); |
| LOG.info("mknod output:\n"+output); |
| } catch (IOException ex) { |
| LOG.info("IO error running mknod: " + ex.getMessage()); |
| LOG.debug("IO error running mknod", ex); |
| } |
| if (!this.fifoFile.exists()) { |
| LOG.info("mknod failed, falling back to mkfifo"); |
| String output = Shell.execCommand("mkfifo", "-m", "0" + modeStr, |
| filename); |
| LOG.info("mkfifo output:\n"+output); |
| } |
| |
| // Schedule the FIFO to be cleaned up when we exit. |
| this.fifoFile.deleteOnExit(); |
| } |
| } |