Package com.aelitis.azureus.core.diskmanager.file.impl

Source Code of com.aelitis.azureus.core.diskmanager.file.impl.FMFileAccessLinear

/*
* Created on 28-Sep-2005
* Created by Paul Gardner
* Copyright (C) 2005, 2006 Aelitis, All Rights Reserved.
*
* This program 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
* 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 General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*
* AELITIS, SAS au capital de 46,603.30 euros
* 8 Allee Lenotre, La Grille Royale, 78600 Le Mesnil le Roi, France.
*
*/

package com.aelitis.azureus.core.diskmanager.file.impl;

import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.channels.FileChannel.MapMode;

import org.gudy.azureus2.core3.util.AEThread2;
import org.gudy.azureus2.core3.util.Debug;
import org.gudy.azureus2.core3.util.DirectByteBuffer;
import org.gudy.azureus2.core3.util.SystemTime;

import com.aelitis.azureus.core.diskmanager.file.FMFileManagerException;

public class
FMFileAccessLinear
  implements FMFileAccess
{
  private static final int   WRITE_RETRY_LIMIT    = 10;
  private static final int  WRITE_RETRY_DELAY    = 100;
 
  private static final int   READ_RETRY_LIMIT    = 10;
  private static final int  READ_RETRY_DELAY    = 100;
 
  private static final boolean  DEBUG      = true;
  private static final boolean  DEBUG_VERBOSE  = false;
 
  private static final boolean USE_MMAP = System.getProperty("azureus.io.usemmap","false") == "true";

  private FMFileImpl    owner;
 
  protected
  FMFileAccessLinear(
    FMFileImpl    _owner )
  {
    owner  = _owner;
  }
 
  public void
  aboutToOpen()
 
    throws FMFileManagerException
  {
  }
 
  public long
  getLength(
    RandomAccessFile    raf )
 
    throws FMFileManagerException
  {
    try{
      AEThread2.setDebug( owner );
     
      return( raf.length());
     
    }catch( Throwable e ){
     
      throw( new FMFileManagerException( "getLength fails", e ));
    }
  }
 
  public void
  setLength(
    RandomAccessFile    raf,
    long          length )
 
    throws FMFileManagerException
  {
    try{
      AEThread2.setDebug( owner );
     
      raf.setLength( length );
     
    }catch( Throwable e ){
     
      throw( new FMFileManagerException( "setLength fails", e ));
    }
  }
 
  public boolean
  isPieceCompleteProcessingNeeded(
    int          piece_number )
  {
    return( false );
  }
 
  public void
  setPieceComplete(
    RandomAccessFile  raf,
    int          piece_number,
    DirectByteBuffer  piece_data )
 
    throws FMFileManagerException
 
  }
 
  public void
  read(
    RandomAccessFile  raf,
    DirectByteBuffer  buffer,
    long        offset )
 
    throws FMFileManagerException
  {
    if (raf == null){
     
      throw new FMFileManagerException( "read: raf is null" );
    }
   
    FileChannel fc = raf.getChannel();
       
    if ( !fc.isOpen()){
     
      Debug.out("FileChannel is closed: " + owner.getName());
     
      throw( new FMFileManagerException( "read - file is closed"));
    }

    AEThread2.setDebug( owner );
   
    try{
      if(USE_MMAP)
      {
        long remainingInFile = fc.size()-offset;
        long remainingInTargetBuffer = buffer.remaining(DirectByteBuffer.SS_FILE);
        MappedByteBuffer buf = fc.map(MapMode.READ_ONLY, offset, Math.min(remainingInFile,remainingInTargetBuffer));
        buffer.put(DirectByteBuffer.SS_FILE, buf);
      } else {
        fc.position(offset);
        while (fc.position() < fc.size() && buffer.hasRemaining(DirectByteBuffer.SS_FILE))
          buffer.read(DirectByteBuffer.SS_FILE,fc);       
      }

     
     
    }catch ( Exception e ){
     
      Debug.printStackTrace( e );
     
      throw( new FMFileManagerException( "read fails", e ));
    }
  }
 
  public void
  read(
    RandomAccessFile  raf,
    DirectByteBuffer[]  buffers,
    long        offset )
 
    throws FMFileManagerException
  {
    if ( raf == null ){
     
      throw new FMFileManagerException( "read: raf is null" );
    }
   
    FileChannel fc = raf.getChannel();
       
    if ( !fc.isOpen()){
     
      Debug.out("FileChannel is closed: " + owner.getName());
     
      throw( new FMFileManagerException( "read - file is closed"));
    }
   
    AEThread2.setDebug( owner );
   
    int[]  original_positions = new int[buffers.length];
   
    long read_start = SystemTime.getHighPrecisionCounter();
   
    try{
      if(USE_MMAP)
      {
       
        long size = 0;
        for(int i=0;i<buffers.length;i++)
        {
          size += buffers[i].remaining(DirectByteBuffer.SS_FILE);
          original_positions[i] = buffers[i].position(DirectByteBuffer.SS_FILE);
        }
         
        size = Math.min(size, fc.size()-offset);
        MappedByteBuffer buf = fc.map(MapMode.READ_ONLY, offset, size);
        for(DirectByteBuffer b : buffers)
        {
          buf.limit(buf.position()+b.remaining(DirectByteBuffer.SS_FILE));
          b.put(DirectByteBuffer.SS_FILE, buf);
        }
         
       
      } else {
       
        fc.position(offset);
        ByteBuffer[]  bbs = new ByteBuffer[buffers.length];
       
        ByteBuffer  last_bb  = null;
        for (int i=0;i<bbs.length;i++){
          ByteBuffer bb = bbs[i] = buffers[i].getBuffer(DirectByteBuffer.SS_FILE);
          int  pos = original_positions[i] = bb.position();
          if ( pos != bb.limit()){
            last_bb  = bbs[i];
          }
        }
       
        if ( last_bb != null ){
          int    loop      = 0;
         
            // we sometimes read off the end of the file (when rechecking) so
            // bail out if we've completed the read or got to file end
            // a "better" fix would be to prevent the over-read in the first
            // place, but hey, we're just about to release and there may be other
            // instances of this...

          while ( fc.position() < fc.size() && last_bb.hasRemaining()){
            long  read = fc.read( bbs );
            if ( read > 0 ){
              loop  = 0;
            }else{
              loop++;
              if ( loop == READ_RETRY_LIMIT ){
                Debug.out( "FMFile::read: zero length read - abandoning" );
                throw( new FMFileManagerException( "read fails: retry limit exceeded"));
              }
              if ( DEBUG_VERBOSE )
                Debug.out( "FMFile::read: zero length read - retrying" );

              try{
                Thread.sleep( READ_RETRY_DELAY*loop );
              }catch( InterruptedException e ){
                throw( new FMFileManagerException( "read fails: interrupted" ));
              }
             
            }           
          }
        }

       
      }
    }catch ( Throwable e ){
     
      try{
        Debug.out( "Read failed: " + owner.getString() + ": raf open=" + raf.getChannel().isOpen() + ", len=" + raf.length() + ",off=" + offset );
       
      }catch( IOException f ){
      }
     
      Debug.printStackTrace( e );
     
      if ( original_positions != null ){
     
        try{
          for (int i=0;i<original_positions.length;i++){
           
            buffers[i].position( DirectByteBuffer.SS_FILE, original_positions[i] );
           
          }
        }catch( Throwable e2 ){
         
          Debug.out( e2 );
        }
      }
     
      throw( new FMFileManagerException( "read fails", e ));
     
    }finally{
     
      long elapsed_millis = ( SystemTime.getHighPrecisionCounter() - read_start )/1000000;

      if ( elapsed_millis > 10*1000 ){
       
        System.out.println( "read took " + elapsed_millis + " for " + owner.getString());
      }
    }
  }
 
  public void
  write(
    RandomAccessFile    raf,
    DirectByteBuffer[]    buffers,
    long          position )
 
    throws FMFileManagerException
  {
    if ( raf == null){
      throw( new FMFileManagerException( "write fails: raf is null" ));
    }
   
    FileChannel fc = raf.getChannel();
   
    if ( !fc.isOpen()){
     
      Debug.out("FileChannel is closed: " + owner.getName());
     
      throw( new FMFileManagerException( "read - file is closed"));
    }

    AEThread2.setDebug( owner );
   
    int[]  original_positions = new int[buffers.length];

    try{
     
      if(USE_MMAP) {
        long size = 0;
        for(int i=0;i<buffers.length;i++)
        {
          size += buffers[i].remaining(DirectByteBuffer.SS_FILE);
          original_positions[i] = buffers[i].position(DirectByteBuffer.SS_FILE);
        }
       
        if(position+size > fc.size())
        {
          fc.position(position+size-1);
          fc.write(ByteBuffer.allocate(1));
          fc.force(true);
        }
         
        MappedByteBuffer buf = fc.map(MapMode.READ_WRITE, position, size);
        for(DirectByteBuffer b : buffers)
          buf.put(b.getBuffer(DirectByteBuffer.SS_FILE));
        buf.force();
      } else {
        long  expected_write   = 0;
        long  actual_write  = 0;
        boolean  partial_write  = false;
       
        if ( DEBUG ){
          for (int i=0;i<buffers.length;i++){
            expected_write += buffers[i].limit(DirectByteBuffer.SS_FILE) - buffers[i].position(DirectByteBuffer.SS_FILE);
          }
        }
       
        fc.position( position );
        ByteBuffer[]  bbs = new ByteBuffer[buffers.length];


        ByteBuffer  last_bb  = null;
        for (int i=0;i<bbs.length;i++){
          ByteBuffer bb = bbs[i] = buffers[i].getBuffer(DirectByteBuffer.SS_FILE);
          int  pos = original_positions[i] = bb.position();
          if ( pos != bb.limit()){
            last_bb  = bbs[i];
          }
        }
       
        if ( last_bb != null ){
          int loop = 0;
         
          while( last_bb.position() != last_bb.limit()){
            long written = fc.write( bbs );
            actual_write += written;
           
            if ( written > 0 ){
              loop  = 0;
              if ( DEBUG ){
                if ( last_bb.position() != last_bb.limit()){
                  partial_write  = true;
                  if ( DEBUG_VERBOSE ){
                    Debug.out( "FMFile::write: **** partial write **** this = " + written + ", total = " + actual_write + ", target = " + expected_write );
                  }
                }
              }
             
            }else{
              loop++;
              if ( loop == WRITE_RETRY_LIMIT ){
                Debug.out( "FMFile::write: zero length write - abandoning" );
                throw( new FMFileManagerException( "write fails: retry limit exceeded"));
              }
               
              if ( DEBUG_VERBOSE )
                Debug.out( "FMFile::write: zero length write - retrying" );
             
              try{
                Thread.sleep( WRITE_RETRY_DELAY*loop );
              }catch( InterruptedException e ){
                throw( new FMFileManagerException( "write fails: interrupted" ));
              }
            }           
          }
        }
       
        if ( DEBUG ){
          if ( expected_write != actual_write ){
            Debug.out( "FMFile::write: **** partial write **** failed: expected = " + expected_write + ", actual = " + actual_write );
            throw( new FMFileManagerException( "write fails: expected write/actual write mismatch" ));
          }
          if ( partial_write && DEBUG_VERBOSE )
            Debug.out( "FMFile::write: **** partial write **** completed ok" );
        }
       
      }

     
    }catch ( Throwable e ){
       
      if ( original_positions != null ){
       
        try{
          for (int i=0;i<original_positions.length;i++){
           
            buffers[i].position( DirectByteBuffer.SS_FILE, original_positions[i] );
           
          }
        }catch( Throwable e2 ){
         
          Debug.out( e2 );
        }
      }
     
      throw( new FMFileManagerException( "write fails", e ));
    }   
  }
 
  public void
  flush()
 
    throws FMFileManagerException
  {
    // no state to flush
  }
 
  public FMFileImpl
  getFile()
  {
    return( owner );
  }
 
  public String
  getString()
  {
    return( "linear" );
  }
}
TOP

Related Classes of com.aelitis.azureus.core.diskmanager.file.impl.FMFileAccessLinear

TOP
Copyright © 2018 www.massapi.com. All rights reserved.
All source code are property of their respective owners. Java is a trademark of Sun Microsystems, Inc and owned by ORACLE Inc. Contact coftware#gmail.com.