Wrum, wrum, wrum. Java is awesome at parsing binary files.
Justyna Ilczuk
parent
0252245893
commit
c3df7b0c97
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@ -0,0 +1,23 @@
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/*
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* To change this template, choose Tools | Templates
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* and open the template in the editor.
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*/
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package mobireader;
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import nl.flotsam.preon.annotation.BoundNumber;
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/**
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*
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* @author att
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*/
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public class EXTHHeader {
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//headerfmt = '>III'
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@BoundNumber(size="32")
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long identifier;
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@BoundNumber(size="32")
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long headerLength;
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@BoundNumber(size="32")
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long recordCount;
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}
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@ -0,0 +1,29 @@
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/*
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* To change this template, choose Tools | Templates
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* and open the template in the editor.
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*/
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package mobireader;
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import nl.flotsam.preon.annotation.BoundNumber;
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import nl.flotsam.preon.annotation.BoundString;
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/**
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*
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* @author att
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*/
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public class Header {
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public @BoundString(size="32") String name;
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@BoundNumber int attributes;
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@BoundNumber int version;
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@BoundNumber int created;
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@BoundNumber int modified;
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@BoundNumber int backup;
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@BoundNumber int modnum;
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@BoundNumber int appInfoId;
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@BoundNumber int sortInfoId;
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@BoundString(size="4") String type;
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@BoundString(size="4") String creator;
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@BoundNumber int uniqueIDseed;
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@BoundNumber int nextRecordListId;
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@BoundNumber int number_of_records;
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}
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@ -0,0 +1,172 @@
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/*
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* To change this template, choose Tools | Templates
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* and open the template in the editor.
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*/
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package mobireader;
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import com.google.common.io.Files;
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import java.io.File;
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import java.io.FileInputStream;
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import java.io.FileNotFoundException;
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import java.io.IOError;
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import java.io.IOException;
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import java.io.ObjectInputStream;
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import java.util.HashMap;
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import nl.flotsam.preon.Codec;
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import nl.flotsam.preon.Codecs;
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import nl.flotsam.preon.DecodingException;
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import nl.flotsam.preon.annotation.BoundNumber;
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import nl.flotsam.preon.annotation.BoundString;
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/**
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*
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* @author att
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*/
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public class Mobi {
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File file;
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int offset = 0;
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String contents;
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Header header;
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public Mobi(String filename)
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{
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try {
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this.file = new File(filename);
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}
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catch (IOError e) {
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throw e;
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}
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}
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void parse() throws IOException
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{
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byte compressed [] = Files.toByteArray(this.file);
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this.contents = new String(compressed);
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this.header = parseHeader();
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//this.records = self.parseRecordInfoList();
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//this..readRecord0()
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}
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public int calcsize(String headerFormat)
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{
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int size = 0;
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boolean is_number = false;
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String number = "";
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String type = "";
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for(int i = 0; i < headerFormat.length(); i++)
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{
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char c = headerFormat.charAt(i);
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if(Character.isDigit(c))
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{
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number += c;
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is_number = true;
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}
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else if (is_number){
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size += addNumberOfBytes(Integer.parseInt(number), c);
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is_number = false;
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number = "";
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}
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else {
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size += addNumberOfBytes(1, c);
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}
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}
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return size;
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}
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int addNumberOfBytes(int n, char c)
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{
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int base;
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switch (c) {
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case 'c': base = 1;
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break;
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case 's': base = 1;
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break;
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case 'b': base = 1;
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break;
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case 'h': base = 2;
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break;
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case 'H': base = 2;
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break;
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case 'i': base = 4;
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break;
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case 'I': base = 4;
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break;
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case 'l': base = 4;
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break;
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case 'L': base = 4;
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break;
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case 'f': base = 4;
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break;
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case 'd': base = 8;
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break;
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default: base = 0;
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break;
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}
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return base * n;
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}
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Header parseHeader(){
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String headerfmt = "32shhIIIIII4s4sIIH";
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int headerlen = calcsize(headerfmt);
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String headerData = this.contents.substring(this.offset,
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this.offset+headerlen);
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Header parsedHeader = new Header(); //createHeaderBasedOn(headerData);
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/*
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# unpack header, zip up into list of tuples
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results = zip(fields, unpack(headerfmt, self.contents[self.offset:self.offset+headerlen]))
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# increment offset into file
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this.offset += headerlen;
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# convert tuple array to dictionary
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resultsDict = utils.toDict(results);
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*/
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return parsedHeader;
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}
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public Header createHeaderBasedOn(File file)
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{
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Header headerFromText;
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try {
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Codec<Header> codec = Codecs.create(Header.class);
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headerFromText = Codecs.decode(codec, file);
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}
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catch( IOException e ){
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System.out.println(e.getCause());
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headerFromText = new Header();
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}
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catch (DecodingException e)
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{
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System.out.println(e.getCause());
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headerFromText = new Header();
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}
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return headerFromText;
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}
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/*
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def readRecord(self, recordnum, disable_compression=False):
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if self.config:
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if self.config['palmdoc']['Compression'] == 1 or disable_compression:
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return self.contents[self.records[recordnum]['record Data Offset']:self.records[recordnum+1]['record Data Offset']];
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elif self.config['palmdoc']['Compression'] == 2:
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result = uncompress_lz77(self.contents[self.records[recordnum]['record Data Offset']:self.records[recordnum+1]['record Data Offset']-self.config['mobi']['extra bytes']])
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return result
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def readImageRecord(self, imgnum):
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if self.config:
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recordnum = self.config['mobi']['First Image index'] + imgnum;
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return self.readRecord(recordnum, disable_compression=True);
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def author(self):
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"Returns the author of the book"
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return self.config['exth']['records'][100]
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def title(self):
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"Returns the title of the book"
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return self.config['mobi']['Full Name']
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*/
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}
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@ -0,0 +1,92 @@
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/*
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* To change this template, choose Tools | Templates
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* and open the template in the editor.
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*/
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package mobireader;
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import nl.flotsam.preon.annotation.BoundNumber;
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import nl.flotsam.preon.annotation.BoundString;
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/**
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*
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* @author att
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*/
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public class MobiHeader {
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//headerfmt = '> IIII II 40s III IIIII IIII I 36s IIII 8s HHIIIII'
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@BoundNumber(size="32")
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long identifier;
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@BoundNumber(size="32")
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long header_length;
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@BoundNumber(size="32")
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long Mobi_type;
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@BoundNumber(size="32")
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long text_Encoding;
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@BoundNumber(size="32")
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long Unique_ID;
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@BoundNumber(size="32")
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long Generator_version;
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@BoundString(size="40")
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String Reserved;
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@BoundNumber(size="32")
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long FirstNonBookIndex;
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@BoundNumber(size="32")
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long FullNameOffset;
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@BoundNumber(size="32")
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long FullNameLength;
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@BoundNumber(size="32")
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long Language;
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@BoundNumber(size="32")
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long InputLanguage;
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@BoundNumber(size="32")
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long OutputLanguage;
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@BoundNumber(size="32")
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long FormatVersion;
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@BoundNumber(size="32")
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long FirstImageIndex;
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@BoundNumber(size="32")
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long FirstHuffRecord;
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@BoundNumber(size="32")
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long HuffRecordCount;
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@BoundNumber(size="32")
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long FirstDATPRecord;
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@BoundNumber(size="32")
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long DATPRecordCount;
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@BoundNumber(size="32")
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long EXTHFlags;
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@BoundString(size="36")
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String unknown36Bytes;
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@BoundNumber(size="32")
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long DRMOffset;
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@BoundNumber(size="32")
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long DRMCount;
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@BoundNumber(size="32")
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long DRMSize;
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@BoundNumber(size="32")
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long DRMFlags;
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@BoundString(size="8")
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String unknown8Bytes;
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@BoundNumber(size="16")
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int Unknown1;
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@BoundNumber(size="16")
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int LastImageRecord;
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@BoundNumber(size="32")
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long Unknown2;
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@BoundNumber(size="32")
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long FCISRecord;
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@BoundNumber(size="32")
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long Unknown3;
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@BoundNumber(size="32")
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long FLISRecord;
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@BoundNumber(size="32")
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long Unknown4;
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}
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@ -34,5 +34,6 @@ public class MobiReader extends Application {
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public static void main(String[] args) {
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launch(args);
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}
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}
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@ -0,0 +1,30 @@
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/*
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* To change this template, choose Tools | Templates
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* and open the template in the editor.
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*/
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package mobireader;
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import nl.flotsam.preon.annotation.BoundNumber;
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/**
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*
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* @author att
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*/
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public class PalmDocHeader {
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//headerfmt = '>HHIHHHH'
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@BoundNumber(size="16")
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int Compression;
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@BoundNumber(size="16")
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int Unused;
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@BoundNumber(size="32")
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long textLength;
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@BoundNumber(size="16")
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int recordCount;
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@BoundNumber(size="16")
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int recordSize;
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@BoundNumber(size="16")
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int encryptionType;
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@BoundNumber(size="16")
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int unknown;
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}
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/*
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* The MIT License
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*
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* Copyright (c) 2009 Olle Törnström studiomediatech.com
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*
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* CREDIT: Initially implemented by Diogo Kollross and made publicly available
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* on the website http://www.geocities.com/diogok_br/lz77. Edited here
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* to provide two flavours for JavaScript usage, either as standalone
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* compressor/decompressor or as class for copy/paste use.
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*/
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/**
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* This class provides simple LZ77 compression and decompression.
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*
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* USAGE: Place in your own project package of choice adding preferred package
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* setting.
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*
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* @author Olle Törnström olle[at]studiomediatech[dot]com
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* @created 2009-02-18
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*/
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package unzipping;
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public class LZ77 {
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private char referencePrefix;
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private int referenceIntBase;
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private int referenceIntFloorCode;
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private int referenceIntCeilCode;
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private int maxStringDistance;
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private int minStringLength;
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private int maxStringLength;
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private int defaultWindowLength;
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private int maxWindowLength;
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// CONSTRUCTOR
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public LZ77() {
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referencePrefix = '`';
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referenceIntBase = 96;
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referenceIntFloorCode = (int) ' ';
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referenceIntCeilCode = referenceIntFloorCode + referenceIntBase;
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maxStringDistance = (int) Math.pow(referenceIntBase, 2) - 1;
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minStringLength = 5;
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maxStringLength = (int) Math.pow(referenceIntBase, 1) - 1
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+ minStringLength;
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defaultWindowLength = 144;
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maxWindowLength = maxStringDistance + minStringLength;
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}
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// LAZY STATIC METHODS - ADDED BY: DAN!
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public static String compressStr(String data) {
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LZ77 lz = new LZ77();
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return lz.compress(data, null);
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}
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public static String decompressStr(String data) {
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LZ77 lz = new LZ77();
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return lz.decompress(data);
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}
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// PUBLIC METHODS
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/**
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* Compress string data using the LZ77 algorithm.
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*
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* @param data
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* String data to compress
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* @return LZ77 compressed string
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*/
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public String compress(String data) {
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return compress(data, null);
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}
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/**
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* Compress string data using the LZ77 algorithm.
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*
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* @param data
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* String data to compress
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* @param windowLength
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* Optional window length
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* @return LZ77 compressed string
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*/
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public String compress(String data, Integer windowLength) {
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if (windowLength == null)
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windowLength = defaultWindowLength;
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if (windowLength > maxWindowLength)
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throw new IllegalArgumentException("Window length too large");
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String compressed = "";
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int pos = 0;
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int lastPos = data.length() - minStringLength;
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while (pos < lastPos) {
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int searchStart = Math.max(pos - windowLength, 0);
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int matchLength = minStringLength;
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boolean foundMatch = false;
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int bestMatchDistance = maxStringDistance;
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int bestMatchLength = 0;
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String newCompressed = null;
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while ((searchStart + matchLength) < pos) {
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int sourceWindowEnd = Math.min(searchStart + matchLength, data
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.length());
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int targetWindowEnd = Math
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.min(pos + matchLength, data.length());
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String m1 = data.substring(searchStart, sourceWindowEnd);
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String m2 = data.substring(pos, targetWindowEnd);
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boolean isValidMatch = m1.equals(m2)
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&& matchLength < maxStringLength;
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if (isValidMatch) {
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matchLength++;
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foundMatch = true;
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} else {
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int realMatchLength = matchLength - 1;
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if (foundMatch && (realMatchLength > bestMatchLength)) {
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bestMatchDistance = pos - searchStart - realMatchLength;
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bestMatchLength = realMatchLength;
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}
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matchLength = minStringLength;
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searchStart++;
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foundMatch = false;
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}
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}
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if (bestMatchLength != 0) {
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newCompressed = referencePrefix
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+ encodeReferenceInt(bestMatchDistance, 2)
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+ encodeReferenceLength(bestMatchLength);
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pos += bestMatchLength;
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} else {
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if (data.charAt(pos) != referencePrefix) {
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newCompressed = "" + data.charAt(pos);
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} else {
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newCompressed = "" + referencePrefix + referencePrefix;
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}
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pos++;
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}
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compressed += newCompressed;
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}
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return compressed + data.substring(pos).replaceAll("/`/g", "``");
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}
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public String decompress(String data) {
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String decompressed = "";
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int pos = 0;
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while (pos < data.length()) {
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char currentChar = data.charAt(pos);
|
||||
|
||||
if (currentChar != referencePrefix) {
|
||||
|
||||
decompressed += currentChar;
|
||||
pos++;
|
||||
|
||||
} else {
|
||||
|
||||
char nextChar = data.charAt(pos + 1);
|
||||
|
||||
if (nextChar != referencePrefix) {
|
||||
|
||||
int distance = decodeReferenceInt(data.substring(pos + 1,
|
||||
pos + 3), 2);
|
||||
|
||||
int length = decodeReferenceLength(data.substring(pos + 3,
|
||||
pos + 4));
|
||||
|
||||
int start = decompressed.length() - distance - length;
|
||||
int end = start + length;
|
||||
decompressed += decompressed.substring(start, end);
|
||||
pos += minStringLength - 1;
|
||||
|
||||
} else {
|
||||
|
||||
decompressed += referencePrefix;
|
||||
pos += 2;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return decompressed;
|
||||
}
|
||||
|
||||
// PRIVATE METHODS
|
||||
|
||||
private String encodeReferenceInt(int value, int width) {
|
||||
|
||||
if ((value >= 0) && (value < (Math.pow(referenceIntBase, width) - 1))) {
|
||||
|
||||
String encoded = "";
|
||||
|
||||
while (value > 0) {
|
||||
char c = (char) ((value % referenceIntBase) + referenceIntFloorCode);
|
||||
encoded = "" + c + encoded;
|
||||
value = (int) Math.floor(value / referenceIntBase);
|
||||
}
|
||||
|
||||
int missingLength = width - encoded.length();
|
||||
|
||||
for (int i = 0; i < missingLength; i++) {
|
||||
char c = (char) referenceIntFloorCode;
|
||||
encoded = "" + c + encoded;
|
||||
}
|
||||
|
||||
return encoded;
|
||||
|
||||
} else {
|
||||
|
||||
throw new IllegalArgumentException("Reference int out of range: "
|
||||
+ value + " (width = " + width + ")");
|
||||
}
|
||||
}
|
||||
|
||||
private String encodeReferenceLength(int length) {
|
||||
|
||||
return encodeReferenceInt(length - minStringLength, 1);
|
||||
}
|
||||
|
||||
private int decodeReferenceInt(String data, int width) {
|
||||
|
||||
int value = 0;
|
||||
|
||||
for (int i = 0; i < width; i++) {
|
||||
|
||||
value *= referenceIntBase;
|
||||
|
||||
int charCode = (int) data.charAt(i);
|
||||
|
||||
if ((charCode >= referenceIntFloorCode)
|
||||
&& (charCode <= referenceIntCeilCode)) {
|
||||
|
||||
value += charCode - referenceIntFloorCode;
|
||||
|
||||
} else {
|
||||
|
||||
throw new RuntimeException(
|
||||
"Invalid char code in reference int: " + charCode);
|
||||
}
|
||||
}
|
||||
|
||||
return value;
|
||||
}
|
||||
|
||||
private int decodeReferenceLength(String data) {
|
||||
|
||||
return decodeReferenceInt(data, 1) + minStringLength;
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,101 @@
|
|||
/*
|
||||
* To change this template, choose Tools | Templates
|
||||
* and open the template in the editor.
|
||||
*/
|
||||
package unzipping;
|
||||
|
||||
/**
|
||||
*
|
||||
* @author att
|
||||
*/
|
||||
public class lz77Unzipper {
|
||||
|
||||
}
|
||||
/*
|
||||
import struct
|
||||
# ported directly from the PalmDoc Perl library
|
||||
# http://kobesearch.cpan.org/htdocs/EBook-Tools/EBook/Tools/PalmDoc.pm.html
|
||||
|
||||
def uncompress_lz77(data):
|
||||
length = len(data);
|
||||
offset = 0; # Current offset into data
|
||||
# char; # Character being examined
|
||||
# ord; # Ordinal of $char
|
||||
# lz77; # 16-bit Lempel-Ziv 77 length-offset pair
|
||||
# lz77offset; # LZ77 offset
|
||||
# lz77length; # LZ77 length
|
||||
# lz77pos; # Position inside $lz77length
|
||||
text = ''; # Output (uncompressed) text
|
||||
# textlength; # Length of uncompressed text during LZ77 pass
|
||||
# textpos; # Position inside $text during LZ77 pass
|
||||
|
||||
while offset < length:
|
||||
# char = substr($data,$offset++,1);
|
||||
char = data[offset];
|
||||
offset += 1;
|
||||
ord_ = ord(char);
|
||||
|
||||
# print " ".join([repr(char), hex(ord_)])
|
||||
|
||||
# The long if-elsif chain is the best logic for $ord handling
|
||||
## no critic (Cascading if-elsif chain)
|
||||
if (ord_ == 0):
|
||||
# Nulls are literal
|
||||
text += char;
|
||||
elif (ord_ <= 8):
|
||||
# Next $ord bytes are literal
|
||||
text += data[offset:offset+ord_] # text .=substr($data,$offset,ord);
|
||||
offset += ord_;
|
||||
elif (ord_ <= 0x7f):
|
||||
# Values from 0x09 through 0x7f are literal
|
||||
text += char;
|
||||
elif (ord_ <= 0xbf):
|
||||
# Data is LZ77-compressed
|
||||
|
||||
# From Wikipedia:
|
||||
# "A length-distance pair is always encoded by a two-byte
|
||||
# sequence. Of the 16 bits that make up these two bytes,
|
||||
# 11 bits go to encoding the distance, 3 go to encoding
|
||||
# the length, and the remaining two are used to make sure
|
||||
# the decoder can identify the first byte as the beginning
|
||||
# of such a two-byte sequence."
|
||||
|
||||
offset += 1;
|
||||
if (offset > len(data)):
|
||||
print("WARNING: offset to LZ77 bits is outside of the data: %d" % offset);
|
||||
return text;
|
||||
|
||||
lz77, = struct.unpack('>H', data[offset-2:offset])
|
||||
|
||||
# Leftmost two bits are ID bits and need to be dropped
|
||||
lz77 &= 0x3fff;
|
||||
|
||||
# Length is rightmost 3 bits + 3
|
||||
lz77length = (lz77 & 0x0007) + 3;
|
||||
|
||||
# Remaining 11 bits are offset
|
||||
lz77offset = lz77 >> 3;
|
||||
if (lz77offset < 1):
|
||||
print("WARNING: LZ77 decompression offset is invalid!");
|
||||
return text;
|
||||
|
||||
# Getting text from the offset is a little tricky, because
|
||||
# in theory you can be referring to characters you haven't
|
||||
# actually decompressed yet. You therefore have to check
|
||||
# the reference one character at a time.
|
||||
textlength = len(text);
|
||||
for lz77pos in range(lz77length): # for($lz77pos = 0; $lz77pos < $lz77length; $lz77pos++)
|
||||
textpos = textlength - lz77offset;
|
||||
if (textpos < 0):
|
||||
print("WARNING: LZ77 decompression reference is before"+
|
||||
" beginning of text! %x" % lz77);
|
||||
return;
|
||||
|
||||
text += text[textpos:textpos+1]; #text .= substr($text,$textpos,1);
|
||||
textlength+=1;
|
||||
else:
|
||||
# 0xc0 - 0xff are single characters (XOR 0x80) preceded by
|
||||
# a space
|
||||
text += ' ' + chr(ord_ ^ 0x80);
|
||||
return text;
|
||||
*/
|
||||
Loading…
Reference in New Issue