/* PlainSocketImpl.java -- Default socket implementation
   Copyright (C) 1998, 1999 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
 
GNU Classpath 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 for more details.

You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.

As a special exception, if you link this library with other files to
produce an executable, this library does not by itself cause the
resulting executable to be covered by the GNU General Public License.
This exception does not however invalidate any other reasons why the
executable file might be covered by the GNU General Public License. */


package java.net;

import java.io.InputStream;
import java.io.OutputStream;
import java.io.IOException;
import gnu.classpath.Configuration;

/**
  * Unless the application installs its own SocketImplFactory, this is the
  * default socket implemetation that will be used.  It simply uses a
  * combination of Java and native routines to implement standard BSD
  * style sockets of family AF_INET and types SOCK_STREAM and SOCK_DGRAM
  *
  * @version 0.1
  *
  * @author Aaron M. Renn (arenn@urbanophile.com)
  */
class PlainSocketImpl extends SocketImpl
{

/*************************************************************************/

/*
 * Static Variables
 */

// Static initializer to load native library
  static
  {
    if (Configuration.INIT_LOAD_LIBRARY)
      {
	System.loadLibrary("javanet");
      }
  }

/*************************************************************************/

/*
 * Instance Variables
 */

/**
  * This is the native file descriptor for this socket
  */
protected int native_fd = -1;

/*************************************************************************/

/*
 * Constructors
 */

/**
  * Default do nothing constructor
  */
public
PlainSocketImpl()
{
  ;
}

/*************************************************************************/

/*
 * Instance Variables
 */

/**
  * Accepts a new connection on this socket and returns in in the 
  * passed in SocketImpl.
  *
  * @param impl The SocketImpl object to accept this connection.
  */
protected native synchronized void accept(SocketImpl impl) throws IOException;

/*************************************************************************/

/**
  * Returns the number of bytes that the caller can read from this socket
  * without blocking. //*****Figure out if we can do something here
  *
  * @return The number of readable bytes before blocking
  *
  * @exception IOException If an error occurs
  */
protected int
available() throws IOException
{
  return(0);
}

/*************************************************************************/

/**
  * Binds to the specified port on the specified addr.  Note that this addr
  * must represent a local IP address.  **** How bind to INADDR_ANY? ****
  *
  * @param addr The address to bind to
  * @param port The port number to bind to
  *
  * @exception IOException If an error occurs
  */
protected native synchronized void bind(InetAddress addr, int port) throws IOException;

/*************************************************************************/

/**
  * Closes the socket.  This will cause any InputStream or OutputStream
  * objects for this Socket to be closed as well.
  * <p>
  * Note that if the SO_LINGER option is set on this socket, then the
  * operation could block.
  *
  * @exception IOException If an error occurs
  */
protected native synchronized void close() throws IOException;

/*************************************************************************/

/**
  * Connects to the remote address and port specified as arguments.
  *
  * @param addr The remote address to connect to
  * @param port The remote port to connect to
  *
  * @exception IOException If an error occurs
  */
protected native synchronized void connect(InetAddress addr, int port) throws IOException;

/*************************************************************************/

/**
  * Connects to the remote hostname and port specified as arguments.
  *
  * @param hostname The remote hostname to connect to
  * @param port The remote port to connect to
  *
  * @exception IOException If an error occurs
  */
protected synchronized void 
connect(String hostname, int port) throws IOException
{
  InetAddress addr = InetAddress.getByName(hostname);
  connect(addr, port);
}

/*************************************************************************/

/**
  * Creates a new socket that is not bound to any local address/port and
  * is not connected to any remote address/port.  This will be created as
  * a stream socket if the stream parameter is true, or a datagram socket
  * if the stream parameter is false.
  *
  * @param stream true for a stream socket, false for a datagram socket
  */
protected native synchronized void create(boolean stream) throws IOException;

/*************************************************************************/

/**
  * Starts listening for connections on a socket. The queuelen parameter
  * is how many pending connections will queue up waiting to be serviced
  * before being accept'ed.  If the queue of pending requests exceeds this
  * number, additional connections will be refused.
  *
  * @param queuelen The length of the pending connection queue
  * 
  * @exception IOException If an error occurs
  */
protected native synchronized void listen(int queuelen) throws IOException;

/*************************************************************************/

/**
  * Internal method used by SocketInputStream for reading data from
  * the connection.  Reads up to len bytes of data into the buffer
  * buf starting at offset bytes into the buffer.
  *
  * @return The actual number of bytes read or -1 if end of stream.
  *
  * @exception IOException If an error occurs
  */
protected native int read(byte[] buf, int offset, int len) throws IOException;

/*************************************************************************/

/**
  * Internal method used by SocketOuputStream for writing data to
  * the connection.  Writes up to len bytes of data from the buffer
  * buf starting at offset bytes into the buffer.
  *
  * @exception IOException If an error occurs
  */
protected native void write(byte[] buf, int offset, int len) throws IOException;

/*************************************************************************/

/**
  * Sets the specified option on a socket to the passed in object.  For
  * options that take an integer argument, the passed in object is an
  * Integer.  The option_id parameter is one of the defined constants in
  * this interface.
  *
  * @param option_id The identifier of the option
  * @param val The value to set the option to
  *
  * @exception SocketException If an error occurs
  */
public native synchronized void setOption(int option_id, Object val) throws SocketException;

/*************************************************************************/

/**
  * Returns the current setting of the specified option.  The Object returned
  * will be an Integer for options that have integer values.  The option_id
  * is one of the defined constants in this interface.
  *
  * @param option_id The option identifier
  *
  * @return The current value of the option
  *
  * @exception SocketException If an error occurs
  */
public native synchronized Object getOption(int option_id) throws SocketException;

/*************************************************************************/

/**
  * Returns an InputStream object for reading from this socket.  This will
  * be an instance of SocketInputStream.
  *
  * @return An InputStream
  *
  * @exception IOException If an error occurs
  */
protected synchronized InputStream
getInputStream() throws IOException
{
  return(new SocketInputStream(this));
}
  
/*************************************************************************/

/**
  * Returns an OutputStream object for writing to this socket.  This will
  * be an instance of SocketOutputStream.
  * 
  * @return An OutputStream
  *
  * @exception IOException If an error occurs
  */
protected synchronized OutputStream
getOutputStream() throws IOException
{
  return(new SocketOutputStream(this));
}

} // class PlainSocketImpl