tdscomm.java

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//
//      for(; i<length; i++)
//      {
//         appendByte(pad);
//      }
//   }


   /**
    * Send the logical packet.
    * <p>
    * Send the logical packet the has been constructed.  */
   public synchronized void sendPacket()
      throws java.io.IOException
   {
      sendPhysicalPacket(true);
      nextOutBufferIndex = 0;
      packetType   = 0;
      notify();
   }


   /**
    * store a byte of data at a particular location in the outBuffer.
    *
    * @param index position in outBuffer to store data
    * @param value value to store in the outBuffer.
    */
   private void storeByte(
      int   index,
      byte  value)
   {
      outBuffer[index] = value;
      
   }

   /**
    * store a short integer of data at a particular location in the outBuffer.
    *
    * @param index position in outBuffer to store data
    * @param value value to store in the outBuffer.
    */
   private void storeShort(
      int   index,
      short s)
   {
      outBuffer[index] = (byte)((s>>8) & 0xff);
      outBuffer[index+1] = (byte)((s>>0) & 0xff);
   }


   /**
    * send the data in the outBuffer.
    * <p>
    * Fill in the TDS packet header data and send the data in outBuffer
    * to the DB server.
    *
    * @param isLastSegment is this the last physical packet that makes
    *        up the physical packet?
    */
   private void sendPhysicalPacket(boolean isLastSegment)
      throws java.io.IOException
   {
      if (nextOutBufferIndex>headerLength
         || packetType == CANCEL)
      {
         // packet type
         storeByte(0, (byte)(packetType & 0xff));
         storeByte(1, isLastSegment ? (byte)1 : (byte)0);
         storeShort(2, (short)nextOutBufferIndex);
         storeByte(4, (byte)0);
         storeByte(5, (byte)0);
         storeByte(6, (byte)(tdsVer == TDS70 ? 1 : 0));
         storeByte(7, (byte)0);
			//Dusan
			z++;
/*      	if (z==7) {
      		
      		storeByte(18, "1".getBytes()[0]);
      		storeByte(20, (byte)0);
      		storeByte(21, "#".getBytes()[0]);
      		storeByte(22, "1".getBytes()[0]);
      		storeByte(23, "(".getBytes()[0]);
      		storeByte(24, "@".getBytes()[0]);
      		storeByte(25, "P".getBytes()[0]);
      		storeByte(26, "1".getBytes()[0]);
      		storeByte(31, (byte)0);
      		
}      		
*/      	
         out.write(outBuffer, 0, nextOutBufferIndex);
         packetsSent++;
        	for(int j=0; j < outBuffer.length; j++) 
      		storeByte(j, (byte)0);


         if (Logger.isActive())
         {
            String  dump = HexDump.hexDump(outBuffer, nextOutBufferIndex);
            String  t    = (new Timestamp(
               System.currentTimeMillis())).toString();
            Logger.println("Instance " + id + " @ " + t 
                           + " sent packet #" + packetsSent + "\n" + dump);
         }
      }
   }

   /**
    * peek at the next byte of data.
    * <p>
    * This returns the next byte of data that would be returned
    * by getByte(), but does not actually consume the data.
    *
    * <b>Note-</b>  We can't synchronize this method (or most of the other
    * methods in this class) because of the way cancels are handled.  
    * If a thread is waiting for a response from the server the
    * cancelController class must be able to call sendPacket() to 
    * cancel the request.
    *
    * @return The next byte of data that will be returned by getByte()
    *
    * @exception com.internetcds.jdbc.tds.TdsException
    * @exception java.io.IOException
    */
   public byte peek()
      throws  com.internetcds.jdbc.tds.TdsException,
      java.io.IOException
   {
      
      // XXX RACE CONDITION-  It is possible that two threads
      // could be modifying inBuffer at the same time.  We need 
      // to synchronized based on inBuffer itself.
      byte   result = getByte();
      backup();
      return result;
   }


   /**
    * put the most recently read byte of data back in the inBuffer.
    * <p>
    * This function effectivly ungets the last byte read.
    * It is guaranteed to be able to unget the last byte read.
    * Trying to unget multiple bytes is not recomended and will
    * only work so long as all the bytes were in the same
    * physical TDS network packet.
    *
    * @author Craig Spannring
    */
   public void backup()
   {
      inBufferIndex--;

      // make sure we have fallen of the beginning of the buffer
      // throw an array out of bounds error if we've gone back too far.
      byte  b = inBuffer[inBufferIndex];
   }


   /**
    * read a byte of data from the DB server.
    * <p>
    * This will return the next byte of data from the DB server.
    * <p>
    * <B>Warning</B>  If there is not data available this method
    * will block.
    */
   public byte getByte()
      throws  com.internetcds.jdbc.tds.TdsException,
      java.io.IOException
   {
      byte   result;

      if (inBufferIndex >= inBufferLen)
      {
         // out of data, read another physical packet.
         getPhysicalPacket();
      }

      result = inBuffer[inBufferIndex++];
      return result;
   }

   public byte[] getBytes(int len)
      throws com.internetcds.jdbc.tds.TdsException,
      java.io.IOException
   {
      byte result[] = new byte[len];
      int  i;

      for(i=0; i<len; i++)
      {
         result[i] = getByte();
      }
      
      return result;
   }

   /**
    * Reads bytes or characters (depending on TDS version) and constructs a
    * string with them.
    *
    * Sybase will let the client choose byte ordering, but SQLServer 7.0
    * wants little endian only.  In the interest of simplicity, just use
    * little endian regardless of the type of server.
    *
    * Added 2000-06-05.
    */
   public String getString(int len)
      throws com.internetcds.jdbc.tds.TdsException,
      java.io.IOException
   {
      if (tdsVer == TDS70) {
         char[] chars = new char[len];
         for (int i = 0; i < len; ++i) {
            int lo = getByte() & 0xFF;
            int hi = getByte() & 0xFF;
            chars[i] = (char)(lo | (hi << 8));
         }
         return new String(chars);
      }
      else
         return new String(getBytes(len));
   }

   public void skip(int i)
      throws com.internetcds.jdbc.tds.TdsException,
      java.io.IOException
   {
      for(; i>0; i--)
      {
         getByte();
      }
   } // skip()

   public int getNetShort()
      throws TdsException, java.io.IOException
   {
      byte tmp[] = new byte[2];
      tmp[0] = getByte();
      tmp[1] = getByte();
      return ntohs(tmp, 0);
   }

   public int getTdsShort()
      throws com.internetcds.jdbc.tds.TdsException, java.io.IOException
   {
      int lo = ((int)getByte() & 0xff);
      int hi = ((int)getByte() & 0xff) << 8;
      return lo | hi;
   }

   public int getTdsInt()
      throws com.internetcds.jdbc.tds.TdsException, java.io.IOException
   {
      int   result;

      int b1 = ((int)getByte() & 0xff);
      int b2 = ((int)getByte() & 0xff) << 8;
      int b3 = ((int)getByte() & 0xff) << 16;
      int b4 = ((int)getByte() & 0xff) << 24;

      result =  b4 | b3 | b2 | b1;

      return result;
   }

   public long getTdsInt64()
      throws com.internetcds.jdbc.tds.TdsException, java.io.IOException
   {
      long b1 = ((long)getByte() & 0xff);
      long b2 = ((long)getByte() & 0xff) << 8;
      long b3 = ((long)getByte() & 0xff) << 16;
      long b4 = ((long)getByte() & 0xff) << 24;
      long b5 = ((long)getByte() & 0xff) << 32;
      long b6 = ((long)getByte() & 0xff) << 40;
      long b7 = ((long)getByte() & 0xff) << 48;
      long b8 = ((long)getByte() & 0xff) << 56;
      return b1 | b2 | b3 | b4 | b5 | b6 | b7 | b8;
   }


   /**
    * convert two bytes in a byte array into a Java short integer.
    *
    * @param buf array of data
    * @param offset index into the buf array where the short integer
    *               is stored.
    */
   private static int ntohs(byte buf[], int offset)
   {
      int  lo = ((int)buf[offset+1] & 0xff);
      int  hi = (((int)buf[offset] & 0xff) << 8);

      return hi | lo;  // return an int since we really want an _unsigned_
   }

   /**
    * Read a physical packet.
    * <p>
    * <B>Warning</B> This method will block until it gets all of the input.
    */
   private void getPhysicalPacket()
      throws TdsException, java.io.IOException
   {
      byte   tmpBuf[] = new byte[8];


      // read the header
      for (int nread = 0; nread < 8; )
      {
         nread += in.read(tmpBuf, nread, 8 - nread);
      }
      if (Logger.isActive())
      {
         String  dump = com.internetcds.util.HexDump.hexDump(tmpBuf, 8);
         String  t    = (new Timestamp(
            System.currentTimeMillis())).toString();

         Logger.println("Instance "  + id + " @ " + t 
                        + " recevied header #" + (packetsReceived+1) 
                        + "\n" + dump);
      }
      byte   packetType = tmpBuf[0];
      if (packetType!=LOGON
          && packetType!=QUERY
          && packetType!=REPLY)
      {
         throw new TdsUnknownPacketType(packetType, tmpBuf);
      }
      // figure out how many bytes are remaining in this packet.
      int len = ntohs(tmpBuf, 2) - 8;
      // Added 2000-06-05
      if (len >= inBuffer.length)
      {
          inBuffer = new byte[len];
      }
      if (len < 0)
      {
         throw new TdsException("Confused by a length of " + len);
      }

      // now get the data
      for (int nread = 0; nread < len; )
      {
			//Dusan1

         nread += in.read(inBuffer, nread, len - nread);
      }
      packetsReceived++;


      // adjust the bookkeeping info about the incoming buffer
      inBufferLen   = len;
      inBufferIndex = 0;

      if (Logger.isActive())
      {
         String  dump = com.internetcds.util.HexDump.hexDump(inBuffer, len);
         String  t    = (new Timestamp(
            System.currentTimeMillis())).toString();

         Logger.println("Instance "  + id + " @ " + t 
                        + " recevied data #" + (packetsReceived) 
                        + "\n" + dump);
      }
   }
}