UnixSocketInputStream.java

/*******************************************************************************
 * Copyright (c) 2012-2017 Codenvy, S.A.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *   Codenvy, S.A. - initial API and implementation
 *******************************************************************************/
package org.eclipse.che.plugin.docker.client.connection;

import org.eclipse.che.plugin.docker.client.CLibrary;
import com.sun.jna.LastErrorException;

import java.io.IOException;
import java.io.InputStream;

import static org.eclipse.che.plugin.docker.client.CLibraryFactory.getCLibrary;

/**
* @author andrew00x
*/
public class UnixSocketInputStream extends InputStream {
    private final int fd;
    private final CLibrary cLib = getCLibrary();

    UnixSocketInputStream(int fd) {
        this.fd = fd;
    }

    @Override
    public int read() throws IOException {
        final byte[] bytes = new byte[1];
        if (read(bytes) == 0) {
            return -1;
        }
        return bytes[0];
    }

    @Override
    public int read(byte[] b) throws IOException {
        return read(b, 0, b.length);
    }

    @Override
    public int read(byte[] b, int off, int len) throws IOException {
        if (b == null) {
            throw new NullPointerException();
        }
        if (off < 0 || len < 0 || len > b.length - off) {
            throw new IndexOutOfBoundsException();
        }
        if (len == 0) {
            return 0;
        }
        int n;
        try {
            n = cLib.recv(fd, b, len, 0);
        } catch (LastErrorException e) {
            throw new IOException("error: " + cLib.strerror(e.getErrorCode()));
        }
        if (n == 0) {
            return -1;
        }
        return n;
    }
}