# NIONetSocket.java

    /*
    ** Module   : NIONetSocket.java
    ** Abstract : Implements NetSocket operations which are specific for insecure channels.
    **
    ** Copyright (c) 2016-2023, Golden Code Development Corporation.
    **
    ** -#- -I- --Date--  ---------------------------------------Description---------------------------------------
    ** 001 IAS 20160805  Initial version
    ** 002 IAS 20200725  Fixed read of large messages
    ** 003 GBB 20230512  Logging methods replaced by CentralLogger/ConversionStatus.
    */
    /*
    ** This program is free software: you can redistribute it and/or modify
    ** it under the terms of the GNU Affero General Public License as
    ** published by the Free Software Foundation, either version 3 of the
    ** License, or (at your option) any later version.
    **
    ** This program 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 Affero General Public License for more details.
    **
    ** You may find a copy of the GNU Affero GPL version 3 at the following
    ** location: https://www.gnu.org/licenses/agpl-3.0.en.html
    **
    ** Additional terms under GNU Affero GPL version 3 section 7:
    **
    **   Under Section 7 of the GNU Affero GPL version 3, the following additional
    **   terms apply to the works covered under the License.  These additional terms
    **   are non-permissive additional terms allowed under Section 7 of the GNU
    **   Affero GPL version 3 and may not be removed by you.
    **
    **   0. Attribution Requirement.
    **
    **     You must preserve all legal notices or author attributions in the covered
    **     work or Appropriate Legal Notices displayed by works containing the covered
    **     work.  You may not remove from the covered work any author or developer
    **     credit already included within the covered work.
    **
    **   1. No License To Use Trademarks.
    **
    **     This license does not grant any license or rights to use the trademarks
    **     Golden Code, FWD, any Golden Code or FWD logo, or any other trademarks
    **     of Golden Code Development Corporation. You are not authorized to use the
    **     name Golden Code, FWD, or the names of any author or contributor, for
    **     publicity purposes without written authorization.
    **
    **   2. No Misrepresentation of Affiliation.
    **
    **     You may not represent yourself as Golden Code Development Corporation or FWD.
    **
    **     You may not represent yourself for publicity purposes as associated with
    **     Golden Code Development Corporation, FWD, or any author or contributor to
    **     the covered work, without written authorization.
    **
    **   3. No Misrepresentation of Source or Origin.
    **
    **     You may not represent the covered work as solely your work.  All modified
    **     versions of the covered work must be marked in a reasonable way to make it
    **     clear that the modified work is not originating from Golden Code Development
    **     Corporation or FWD.  All modified versions must contain the notices of
    **     attribution required in this license.
    */

    package com.goldencode.p2j.net;

    import com.goldencode.p2j.util.logging.*;

    import java.io.*;
    import java.nio.*;
    import java.nio.channels.*;
    import java.util.logging.*;

    import javax.net.ssl.*;

    /**
     * Implements NetSocket operations which are specific for insecure channels
     */
    class NIONetSocket
    extends NIONetSocketBase
    {
       /** Logger. */
       private static final CentralLogger LOG = CentralLogger.get(NIONetSocket.class);

       /** read buffer */
       protected final ByteBuffer rbuf;

       /**
        * Constructor
        *
        * @param channel
        *        underlying SocketChannel
        * @throws   IOException
        *           on error
        */
       public NIONetSocket(SocketChannel channel)
       throws IOException
       {
          super(channel);
          this.rbuf = ByteBuffer.allocateDirect(BUF_SIZE);
       }

       /**
        * Gets the SSL session.
        *
        * @return   The SSL session or <code>null</code> if the socket is not
        *           secure.
        */
       public SSLSession getSession()
       {
          return null;
       }

       /**
        * Send the data to the channel
        *
        * @param bb
        *        data to be sent
        */
      protected void write(ByteBuffer bb) throws IOException
       {
          @SuppressWarnings("unused")
          int n = 0;
          while(bb.hasRemaining())
          {
             n += channel.write(bb);
          }
       }

       /**
        * Read next data chunk from the channel
        *
        * @return next data chunk
        */
       @Override
       protected synchronized byte[] readFully() throws IOException, EOFException
       {
          boolean isFinestLoggable = LOG.isLoggable(Level.FINEST);
          int n;
          while (rbuf.position() < 4)
          {
             n = channel.read(rbuf);
             if (n < 0)
             {
                throw new EOFException();
             }
          }
          int pos = rbuf.position();
          rbuf.rewind();
          int len = rbuf.getInt();
          int remains = len;
          int bpos = 0;
          int rbpos = 4;
          int clen;
          byte[] input = new byte[len];
          rbuf.position(pos);
          while (rbuf.position() < rbpos + remains)
          {
             int bytesToRead = 0;
             n = channel.read(rbuf);
             if (n < 0)
             {
                throw new EOFException();
             }
             clen = rbuf.position();
             if (clen == BUF_SIZE)
             {
                rbuf.flip().position(rbpos);
                bytesToRead = Math.min(clen-rbpos, remains);
                if (isFinestLoggable)
                {
                   LOG.log(Level.FINEST, "rbpos: %s, bpos: %s, clen: %s, remains: %s, bytesToRead: %s",
                           rbpos, bpos, clen, remains, bytesToRead);
                }
                rbuf.get(input, bpos, bytesToRead);
                rbuf.compact();
                bpos += Math.min(clen-rbpos, remains);
                rbpos = 0;
             }
             remains = Math.max(0, remains - bytesToRead);
             if (isFinestLoggable)
             {
                LOG.log(Level.FINEST, "rbpos: %s, bpos: %s, clen: %s, remains: %s",
                        rbpos, bpos, rbuf.position(), remains);
             }
          }
          clen = rbuf.position();
          int bytesToRead = Math.min(clen-rbpos, remains);
          if (clen > rbpos)
          {
             if (isFinestLoggable && len > BUF_SIZE)
             {
                LOG.log(Level.FINEST, "rbpos: %s, bpos: %s, clen: %s, remains: %s, bytesToRead: %s",
                         rbpos, bpos, clen, remains, bytesToRead);
             }
             rbuf.flip().position(rbpos);
             rbuf.get(input, bpos, bytesToRead);
             rbuf.compact();
          }
          remains = Math.min(0, remains - bytesToRead);
          if (remains != 0)
          {
             tracef("***** remains == %d", remains);
          }
          return input;
       }
    }