/*
Copyright (c) 2006, Matthew Estes
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
* Neither the name of Metanotion Software nor the names of its
contributors may be used to endorse or promote products derived from this
software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package net.metanotion.io.block;
import java.io.File;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Set;
import net.metanotion.io.RAIFile;
import net.metanotion.io.RandomAccessInterface;
import net.metanotion.io.Serializer;
import net.metanotion.io.data.IntBytes;
import net.metanotion.io.data.LongBytes;
import net.metanotion.io.data.NullBytes;
import net.metanotion.io.data.StringBytes;
import net.metanotion.io.block.index.BSkipList;
class CorruptFileException extends IOException { }
class BadFileFormatException extends IOException { }
class BadVersionException extends IOException { }
public class BlockFile {
public static final long PAGESIZE = 1024;
public static final long OFFSET_MOUNTED = 20;
public RandomAccessInterface file;
private long magicBytes = 0x3141deadbeef0100L;
private long fileLen = PAGESIZE * 2;
private int freeListStart = 0;
private short mounted = 0;
public short spanSize = 127;
private BSkipList metaIndex = null;
private HashMap openIndices = new HashMap();
private void mount() throws IOException {
file.seek(BlockFile.OFFSET_MOUNTED);
mounted = 1;
file.writeShort(mounted);
}
private void writeSuperBlock() throws IOException {
file.seek(0);
file.writeLong( magicBytes);
file.writeLong( fileLen);
file.writeInt( freeListStart);
file.writeShort(mounted);
file.writeShort(spanSize);
}
private void readSuperBlock() throws IOException {
file.seek(0);
magicBytes = file.readLong();
fileLen = file.readLong();
freeListStart = file.readInt();
mounted = file.readShort();
spanSize = file.readShort();
}
public static void main(String args[]) {
try {
RAIFile raif = new RAIFile(new File(args[0]), true, true);
BlockFile bf = new BlockFile(raif, true);
//bf.metaIndex.delete();
bf.makeIndex("foo", new NullBytes(), new NullBytes());
BSkipList b = bf.getIndex("foo", new NullBytes(), new NullBytes());
System.out.println(bf.allocPage());
bf.close();
raif.close();
} catch (Exception e) {
e.printStackTrace();
}
}
public int writeMultiPageData(byte[] data, int page, int[] curPageOff, int[] nextPage) throws IOException {
int pageCounter = curPageOff[0];
int curNextPage = nextPage[0];
int curPage = page;
int dct = 0;
while(dct < data.length) {
int len = ((int) BlockFile.PAGESIZE) - pageCounter;
if(len <= 0) {
if(curNextPage==0) {
curNextPage = this.allocPage();
BlockFile.pageSeek(this.file, curNextPage);
this.file.writeInt(0);
BlockFile.pageSeek(this.file, curPage);
this.file.writeInt(curNextPage);
}
BlockFile.pageSeek(this.file, curNextPage);
curPage = curNextPage;
curNextPage = this.file.readInt();
pageCounter = 4;
len = ((int) BlockFile.PAGESIZE) - pageCounter;
}
this.file.write(data, dct, Math.min(len, data.length - dct));
pageCounter += Math.min(len, data.length - dct);
dct += Math.min(len, data.length - dct);
}
nextPage[0] = curNextPage;
curPageOff[0] = pageCounter;
return curPage;
}
public int readMultiPageData(byte[] arr, int page, int[] curPageOff, int[] nextPage) throws IOException {
int pageCounter = curPageOff[0];
int curNextPage = nextPage[0];
int curPage = page;
int dct = 0;
int res;
while(dct < arr.length) {
int len = ((int) BlockFile.PAGESIZE) - pageCounter;
if(len <= 0) {
BlockFile.pageSeek(this.file, curNextPage);
curPage = curNextPage;
curNextPage = this.file.readInt();
pageCounter = 4;
len = ((int) BlockFile.PAGESIZE) - pageCounter;
}
res = this.file.read(arr, dct, Math.min(len, arr.length - dct));
if(res == -1) { throw new IOException(); }
pageCounter += Math.min(len, arr.length - dct);
dct += res;
}
nextPage[0] = curNextPage;
curPageOff[0] = pageCounter;
return curPage;
}
public BlockFile(RandomAccessInterface rai) throws IOException { this(rai, false); }
public BlockFile(RandomAccessFile raf) throws IOException { this(new RAIFile(raf), false); }
public BlockFile(RandomAccessFile raf, boolean init) throws IOException { this(new RAIFile(raf), init); }
public BlockFile(File f, boolean init) throws IOException { this(new RAIFile(f, true, true), init); }
public BlockFile(RandomAccessInterface rai, boolean init) throws IOException {
if(rai==null) { throw new NullPointerException(); }
file = rai;
if(init) {
file.setLength(fileLen);
writeSuperBlock();
BSkipList.init(this, 2, spanSize);
}
readSuperBlock();
if(magicBytes != 0x3141deadbeef0100L) {
if((magicBytes & 0x3141deadbeef0000L) == 0x3141deadbeef0000L) {
throw new BadVersionException();
} else {
throw new BadFileFormatException();
}
}
// if(mounted != 0) { throw new CorruptFileException(); }
if(fileLen != file.length()) { throw new CorruptFileException(); }
mount();
metaIndex = new BSkipList(spanSize, this, 2, new StringBytes(), new IntBytes());
}
public static void pageSeek(RandomAccessInterface file, int page) throws IOException { file.seek((((long)page) - 1L) * BlockFile.PAGESIZE ); }
public int allocPage() throws IOException {
if(freeListStart != 0) {
FreeListBlock flb = new FreeListBlock(file, freeListStart);
if(flb.len > 0) {
flb.len = flb.len - 1;
int page = flb.branches[flb.len];
flb.writeBlock();
return page;
} else {
freeListStart = flb.nextPage;
writeSuperBlock();
return flb.page;
}
}
long offset = file.length();
fileLen = offset + BlockFile.PAGESIZE;
file.setLength(fileLen);
writeSuperBlock();
return ((int) ((long) (offset / BlockFile.PAGESIZE))) + 1;
}
public void freePage(int page) throws IOException {
System.out.println("Free Page " + page);
if(freeListStart == 0) {
freeListStart = page;
FreeListBlock.initPage(file, page);
writeSuperBlock();
return;
}
FreeListBlock flb = new FreeListBlock(file, freeListStart);
if(flb.isFull()) {
FreeListBlock.initPage(file, page);
if(flb.nextPage == 0) {
flb.nextPage = page;
flb.writeBlock();
return;
} else {
flb = new FreeListBlock(file, page);
flb.nextPage = freeListStart;
flb.writeBlock();
freeListStart = page;
writeSuperBlock();
return;
}
}
flb.addPage(page);
flb.writeBlock();
}
public BSkipList getIndex(String name, Serializer key, Serializer val) throws IOException {
Integer page = (Integer) metaIndex.get(name);
if (page == null) { return null; }
BSkipList bsl = new BSkipList(spanSize, this, page.intValue(), key, val);
openIndices.put(name, bsl);
return bsl;
}
public BSkipList makeIndex(String name, Serializer key, Serializer val) throws IOException {
if(metaIndex.get(name) != null) { throw new IOException("Index already exists"); }
int page = allocPage();
metaIndex.put(name, new Integer(page));
BSkipList.init(this, page, spanSize);
BSkipList bsl = new BSkipList(spanSize, this, page, key, val);
openIndices.put(name, bsl);
return bsl;
}
public void delIndex(String name) throws IOException {
Integer page = (Integer) metaIndex.remove(name);
if (page == null) { return; }
NullBytes nb = new NullBytes();
BSkipList bsl = new BSkipList(spanSize, this, page.intValue(), nb, nb);
bsl.delete();
}
public void close() throws IOException {
metaIndex.close();
metaIndex = null;
Set oi = openIndices.keySet();
Iterator i = oi.iterator();
Object k;
while(i.hasNext()) {
k = i.next();
BSkipList bsl = (BSkipList) openIndices.get(k);
bsl.close();
}
// Unmount.
file.seek(BlockFile.OFFSET_MOUNTED);
file.writeShort(0);
}
}