All Downloads are FREE. Search and download functionalities are using the official Maven repository.

com.caucho.db.io.StoreReadWriteImpl Maven / Gradle / Ivy

/*
 * Copyright (c) 1998-2015 Caucho Technology -- all rights reserved
 *
 * This file is part of Baratine(TM)
 *
 * Each copy or derived work must preserve the copyright notice and this
 * notice unmodified.
 *
 * Baratine 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.
 *
 * Baratine 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, or any warranty
 * of NON-INFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Baratine; if not, write to the
 *
 *   Free Software Foundation, Inc.
 *   59 Temple Place, Suite 330
 *   Boston, MA 02111-1307  USA
 *
 * @author Scott Ferguson
 */

package com.caucho.db.io;

import java.io.IOException;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicReference;
import java.util.logging.Logger;

import com.caucho.util.IoUtil;
import com.caucho.util.L10N;
import com.caucho.vfs.Path;
import com.caucho.vfs.RandomAccessStream;
import com.caucho.vfs.WriteStream;

/**
 * Filesystem access for a random-access store.
 * 
 * The store is designed around a single writer thread and multiple
 * reader threads. When possible, it uses mmap.
 */
public class StoreReadWriteImpl implements StoreReadWrite
{
  private final static Logger log
    = Logger.getLogger(StoreReadWriteImpl.class.getName());
  private final static L10N L = new L10N(StoreReadWriteImpl.class);

  private final Path _path;

  private long _fileSize;

  private final AtomicReference _cachedRead
    = new AtomicReference();
    
  private final AtomicReference _cachedWrite
    = new AtomicReference();
  
  private final AtomicBoolean _isClosed = new AtomicBoolean();

  /**
   * Creates a new store.
   *
   * @param database the owning database.
   * @param name the store name
   * @param lock the table lock
   * @param path the path to the files
   */
  StoreReadWriteImpl(StoreBuilder builder)
  {
    _path = builder.getPath();
    
    _fileSize = Math.max(_path.getLength(), 0);
  }

  /**
   * Returns the file size.
   */
  public long getFileSize()
  {
    return _fileSize;
  }
  
  @Override
  public long getChunkSize()
  {
    return 0x10000;
  }
  
  private void setFileSize(long size)
  {
    _fileSize = Math.max(_fileSize, size);
  }
  
  public long getMmapCloseTimeout()
  {
    return 0;
  }

  /**
   * Creates the store.
   */
  public void create()
    throws IOException
  {
    _path.getParent().mkdirs();

    if (_path.exists()) {
      throw new IOException(L.l("CREATE for path '{0}' failed, because the file already exists.  CREATE can not override an existing table.",
                                _path.getNativePath()));
    }
    
    WriteStream os = null;
    try {
      os = _path.openWrite();
    } finally {
      IoUtil.close(os);
    }
  }

  boolean isFileExist()
  {
    return _path.exists();
  }

  public void init()
    throws IOException
  {
    OutStore os = null;
    try {
      os = openWrite(0, FILE_SIZE_INCREMENT);
      
      setFileSize(os.getLength());
    } finally {
      if (os != null) {
        os.close();
      }
    }
  }

  /**
   * Opens the underlying file to the database.
   */
  @Override
  public InStore openRead(long offset, int size)
  {
    long addressMax = offset + size;
    
    if (getFileSize() < addressMax) {
      throw new IllegalStateException(L.l("{0} read open for length {1} but file length {2}",
                                this, addressMax, getFileSize()));
    }

    InStore is = null;
    try {
      is = openReadImpl(addressMax);

      return is;
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }

  /**
   * Opens the underlying file to the database.
   */
  private InStore openReadImpl(long fileSize)
    throws IOException
  {
    if (_isClosed.get()) {
      throw new IllegalStateException(L.l("{0} is closed.", this));
    }
    
    RandomAccessStream is = _cachedRead.getAndSet(null);

    while (is == null || ! is.allocate()) {
      Path path = _path;
      
      is = null;

      if (path != null) {
        is = streamOpen(fileSize);
      }
      
      if (is != null) {
      }
      else {
        throw new IllegalStateException("Cannot open file");
      }
    }
    
    return new StreamRead(is);
  }

  /**
   * Opens the underlying file to the database.
   */
  public OutStore openWrite(long offset, int size)
  {
    long fileSize = offset + size;
    
    try {
      if (_isClosed.get()) {
        throw new IllegalStateException(L.l("{0} is closed.", this));
      }
      
      RandomAccessStream os = _cachedWrite.getAndSet(null);

      while (os == null || ! os.allocate()) {
        Path path = _path;

        os = null;

        if (path != null) {
          os = streamOpen(fileSize);
        }

        if (os != null) {
        }
        else {
          throw new IllegalStateException("Cannot open file");
        }
      }

      // extendFile(os, fileSize);
    
      return new StreamWrite(os);
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }
  
  private RandomAccessStream streamOpen(long fileSize)
    throws IOException
  {
    if (_isClosed.get()) {
      throw new IllegalStateException();
    }
    
    int retry = 8;
    
    RandomAccessStream s = _path.openRandomAccess();
      
    if (_fileSize < fileSize) {
      extendFile(s, fileSize);
    }
      
    return s;
  }
  
  private long extendFile(RandomAccessStream os, long addressMax)
    throws IOException
  {
    long fileSize = _fileSize;
    
    if (addressMax <= fileSize) {
      return fileSize;
    }
    
    fileSize = extendFileSize(fileSize, _fileSize);
    fileSize = Math.max(fileSize, _path.getLength());
    
    os.write(fileSize - 1, new byte[1], 0, 1);
          
    setFileSize(fileSize);
    
    return _fileSize;
  }
  
  private long extendFileSize(long oldFileSize, long reqFileSize)
  {
    long newFileSize = 5 * oldFileSize / 4 + FILE_SIZE_INCREMENT;
    
    long index = Long.highestOneBit(newFileSize);
    long mask = ~(index - 1) >> 3;

    return Math.max(newFileSize & mask, reqFileSize);
  }
  
  @Override
  public void fsync()
  {
    
  }

  @Override
  public void close()
  {
    if (_isClosed.getAndSet(true)) {
      return;
    }
    
    RandomAccessStream is = _cachedRead.getAndSet(null);

    if (is != null) {
      is.close();
    }
    
    RandomAccessStream os = _cachedWrite.getAndSet(null);

    if (os != null) {
      os.close();
    }
  }

  @Override
  public String toString()
  {
    return getClass().getSimpleName() + "[" + _path + "]";
  }

  class StreamRead implements InStore
  {
    private RandomAccessStream _is;

    StreamRead(RandomAccessStream is)
    {
      _is = is;
    }

    RandomAccessStream getFile()
    {
      return _is;
    }

    @Override
    public boolean read(long address, byte[] buffer, int offset, int length)
    {
      try {
        while (length > 0) {
          int sublen = _is.read(address, buffer, offset, length);
          
          offset += sublen;
          address += sublen;
          length -= sublen;
        }
        
        return true;
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
    }
    
    @Override
    public InStore clone()
    {
      return this;
    }

    @Override
    public void close()
    {
      RandomAccessStream is = _is;
      _is = null;
      
      if (is == null) {
        return;
      }

      is.free();
      
      if (_isClosed.get()) {
        is.close();
      }
      // XXX: cache
      // XXX: _cachedReadFile = this; // XXX:
      else {
        is.close();
      }
    }
    
    public String toString()
    {
      return getClass().getSimpleName() + "[" + _is + "]";
    }
  }


  class StreamWrite implements OutStore
  {
    private RandomAccessStream _os;

    StreamWrite(RandomAccessStream os)
    {
      _os = os;
    }

    RandomAccessStream getFile()
    {
      return _os;
    }
    
    @Override
    public long getLength()
    {
      try {
        return _os.getLength();
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
    }

    @Override
    public boolean write(long address, byte[] buffer, int offset, int length)
    {
      try {
        _os.write(address, buffer, offset, length);

        return true;
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
    }

    /*
    @Override
    public void fsync()
    {
      try {
        _os.fsync();
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
    }

    @Override
    public void fsync(Result cont)
    {
      try {
        _os.fsync();
        
        cont.complete(true);
      } catch (IOException e) {
        cont.fail(e);
        
        throw new RuntimeException(e);
      } catch (Throwable e) {
        cont.fail(e);
        
        throw e;
      }
    }
    */
    
    @Override
    public StreamWrite clone()
    {
      return this;
    }

    @Override
    public void close()
    {
      RandomAccessStream os = _os;
      _os = null;

      if (os == null) {
        return;
      }
      
      os.free();
        
      if (_cachedWrite.compareAndSet(null, os)) {
        return;
      }
        
      os.close();
    }

    @Override
    public String toString()
    {
      return getClass().getSimpleName() + "[" + _os + "]";
    }
  }
}




© 2015 - 2025 Weber Informatics LLC | Privacy Policy