/* jcifs smb client library in Java
 * Copyright (C) 2000  "Michael B. Allen" <jcifs at samba dot org>
 *                     "Paul Walker" <jcifs at samba dot org>
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package jcifs.smb;

import java.net.URL;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.MalformedURLException;
import java.net.UnknownHostException;

/**
 * This class will allow a Java program to read and write data to Named
 * Pipes and Transact NamedPipes.
 *
 * <p>There are three Win32 function calls provided by the Windows SDK
 * that are important in the context of using jCIFS. They are:
 *
 * <ul>
 * <li> <code>CallNamedPipe</code> A message-type pipe call that opens,
 *      writes to, reads from, and closes the pipe in a single operation.
 * <li> <code>TransactNamedPipe</code> A message-type pipe call that
 *      writes to and reads from an existing pipe descriptor in one operation.
 * <li> <code>CreateFile</code>, <code>ReadFile</code>,
 *      <code>WriteFile</code>, and <code>CloseFile</code> A byte-type pipe can
 *      be opened, written to, read from and closed using the standard Win32
 *      file operations.
 * </ul>
 *
 * <p>The jCIFS API maps all of these operations into the standard Java
 * <code>XxxputStream</code> interface. A special <code>PIPE_TYPE</code>
 * flags is necessary to distinguish which type of Named Pipe behavior
 * is desired.
 *
 * <p><table border="1" cellpadding="3" cellspacing="0" width="100%">
 * <tr bgcolor="#ccccff">
 * <td colspan="2"><b><code>SmbNamedPipe</code> Constructor Examples</b></td>
 * <tr><td width="20%"><b>Code Sample</b></td><td><b>Description</b></td></tr>
 * <tr><td width="20%"><pre>
 * new SmbNamedPipe( "smb://server/IPC$/PIPE/foo",
 *         SmbNamedPipe.PIPE_TYPE_RDWR |
 *         SmbNamedPipe.PIPE_TYPE_CALL );
 * </pre></td><td>
 * Open the Named Pipe foo for reading and writing. The pipe will behave like the <code>CallNamedPipe</code> interface.
 * </td></tr>
 * <tr><td width="20%"><pre>
 * new SmbNamedPipe( "smb://server/IPC$/foo",
 *         SmbNamedPipe.PIPE_TYPE_RDWR |
 *         SmbNamedPipe.PIPE_TYPE_TRANSACT );
 * </pre></td><td>
 * Open the Named Pipe foo for reading and writing. The pipe will behave like the <code>TransactNamedPipe</code> interface.
 * </td></tr>
 * <tr><td width="20%"><pre>
 * new SmbNamedPipe( "smb://server/IPC$/foo",
 *         SmbNamedPipe.PIPE_TYPE_RDWR );
 * </pre></td><td>
 * Open the Named Pipe foo for reading and writing. The pipe will
 * behave as though the <code>CreateFile</code>, <code>ReadFile</code>,
 * <code>WriteFile</code>, and <code>CloseFile</code> interface was
 * being used.
 * </td></tr>
 * </table>
 *
 * <p>See <a href="../../../pipes.html">Using jCIFS to Connect to Win32
 * Named Pipes</a> for a detailed description of how to use jCIFS with
 * Win32 Named Pipe server processes.
 *
 */

public class SmbNamedPipe extends SmbFile {

    /**
     * The pipe should be opened read-only.
     */

    public static final int PIPE_TYPE_RDONLY = O_RDONLY;

    /**
     * The pipe should be opened only for writing.
     */

    public static final int PIPE_TYPE_WRONLY = O_WRONLY;

    /**
     * The pipe should be opened for both reading and writing.
     */

    public static final int PIPE_TYPE_RDWR   = O_RDWR;

    /**
     * Pipe operations should behave like the <code>CallNamedPipe</code> Win32 Named Pipe function.
     */

    public static final int PIPE_TYPE_CALL   = 0x0100;

    /**
     * Pipe operations should behave like the <code>TransactNamedPipe</code> Win32 Named Pipe function.
     */

    public static final int PIPE_TYPE_TRANSACT = 0x0200;

    public static final int PIPE_TYPE_DCE_TRANSACT = 0x0200 | 0x0400;

    InputStream pipeIn;
    OutputStream pipeOut;
    int pipeType;

    /**
     * Open the Named Pipe resource specified by the url
     * parameter. The pipeType parameter should be at least one of
     * the <code>PIPE_TYPE</code> flags combined with the bitwise OR
     * operator <code>|</code>. See the examples listed above.
     */

    public SmbNamedPipe( String url, int pipeType )
                            throws MalformedURLException, UnknownHostException {
        super( url );
        this.pipeType = pipeType;
        type = TYPE_NAMED_PIPE;
    }
    public SmbNamedPipe( String url, int pipeType, NtlmPasswordAuthentication auth )
                            throws MalformedURLException, UnknownHostException {
        super( url, auth );
        this.pipeType = pipeType;
        type = TYPE_NAMED_PIPE;
    }
    public SmbNamedPipe( URL url, int pipeType, NtlmPasswordAuthentication auth )
                            throws MalformedURLException, UnknownHostException {
        super( url, auth );
        this.pipeType = pipeType;
        type = TYPE_NAMED_PIPE;
    }

    /**
     * Return the <code>InputStream</code> used to read information
     * from this pipe instance. Presumably data would first be written
     * to the <code>OutputStream</code> associated with this Named
     * Pipe instance although this is not a requirement (e.g. a
     * read-only named pipe would write data to this stream on
     * connection). Reading from this stream may block. Therefore it
     * may be necessary that an addition thread be used to read and
     * write to a Named Pipe.
     */

    public InputStream getNamedPipeInputStream() throws IOException {
        if( pipeIn == null ) {
            if(( pipeType & PIPE_TYPE_CALL ) == PIPE_TYPE_CALL ||
                    ( pipeType & PIPE_TYPE_TRANSACT ) == PIPE_TYPE_TRANSACT ) {
                pipeIn = new TransactNamedPipeInputStream( this );
            } else {
                pipeIn = new SmbFileInputStream(this,
                            (pipeType & 0xFFFF00FF) | SmbFile.O_EXCL);
            }
        }
        return pipeIn;
    }

    /**
     * Return the <code>OutputStream</code> used to write
     * information to this pipe instance. The act of writing data
     * to this stream will result in response data recieved in the
     * <code>InputStream</code> associated with this Named Pipe
     * instance (unless of course it does not elicite a response or the pipe is write-only).
     */

    public OutputStream getNamedPipeOutputStream() throws IOException {
        if( pipeOut == null ) {
            if(( pipeType & PIPE_TYPE_CALL ) == PIPE_TYPE_CALL ||
                    ( pipeType & PIPE_TYPE_TRANSACT ) == PIPE_TYPE_TRANSACT ) {
                pipeOut = new TransactNamedPipeOutputStream( this );
            } else {
                pipeOut = new SmbFileOutputStream(this, false,
                            (pipeType & 0xFFFF00FF) | SmbFile.O_EXCL );
            }
        }
        return pipeOut;
    }
}
