Qt Folder Compression

I needed a compression module that does not depend on anything but Qt, and I mean a module to compress a complete folder with its children. This is because I wanted the compression module to work on any platform supported by Qt with no other dependencies. So I made this modules that only uses only qCompress() & qUncompress() methods plus some logic.

It is mainly a recursive algorithm that serializes data into a single file, each with its relative path to the parent folder. And deserializing is just taking binary data, creating needed subfolders, and saving the file.

Download: QtFolderCompressor.zip

[FolderCompressor.h]

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

#ifndef FOLDERCOMPRESSOR_H #define FOLDERCOMPRESSOR_H   #include <QFile> #include <QObject> #include <QDir>   class FolderCompressor : public QObject {     Q_OBJECT public:     explicit FolderCompressor(QObject *parent = 0);       //A recursive function that scans all files inside the source folder     //and serializes all files in a row of file names and compressed     //binary data in a single file     bool compressFolder(QString sourceFolder, QString destinationFile);       //A function that deserializes data from the compressed file and     //creates any needed subfolders before saving the file     bool decompressFolder(QString sourceFile, QString destinationFolder);   private:     QFile file;     QDataStream dataStream;       bool compress(QString sourceFolder, QString prefex); };   #endif // FOLDERCOMPRESSOR_H

[FolderCompressor.cpp]

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124

#include "FolderCompressor.h"   FolderCompressor::FolderCompressor(QObject *parent) :     QObject(parent) { }   bool FolderCompressor::compressFolder(QString sourceFolder, QString destinationFile) {     QDir src(sourceFolder);     if(!src.exists())//folder not found     {         return false;     }       file.setFileName(destinationFile);     if(!file.open(QIODevice::WriteOnly))//could not open file     {         return false;     }       dataStream.setDevice(&file);       bool success = compress(sourceFolder, "");     file.close();       return success; }   bool FolderCompressor::compress(QString sourceFolder, QString prefex) {     QDir dir(sourceFolder);     if(!dir.exists())         return false;       //1 - list all folders inside the current folder     dir.setFilter(QDir::NoDotAndDotDot | QDir::Dirs);     QFileInfoList foldersList = dir.entryInfoList();       //2 - For each folder in list: call the same function with folders' paths     for(int i=0; i<foldersList.length(); i++)     {         QString folderName = foldersList.at(i).fileName();         QString folderPath = dir.absolutePath()+"/"+folderName;         QString newPrefex = prefex+"/"+folderName;           compress(folderPath, newPrefex);     }       //3 - List all files inside the current folder     dir.setFilter(QDir::NoDotAndDotDot | QDir::Files);     QFileInfoList filesList = dir.entryInfoList();       //4- For each file in list: add file path and compressed binary data     for(int i=0; i<filesList.length(); i++)     {         QFile file(dir.absolutePath()+"/"+filesList.at(i).fileName());         if(!file.open(QIODevice::ReadOnly))//couldn't open file         {             return false;         }           dataStream << QString(prefex+"/"+filesList.at(i).fileName());         dataStream << qCompress(file.readAll());           file.close();     }       return true; }   bool FolderCompressor::decompressFolder(QString sourceFile, QString destinationFolder) {     //validation     QFile src(sourceFile);     if(!src.exists())     {//file not found, to handle later         return false;     }     QDir dir;     if(!dir.mkpath(destinationFolder))     {//could not create folder         return false;     }       file.setFileName(sourceFile);     if(!file.open(QIODevice::ReadOnly))         return false;       dataStream.setDevice(&file);       while(!dataStream.atEnd())     {         QString fileName;         QByteArray data;           //extract file name and data in order         dataStream >> fileName >> data;           //create any needed folder         QString subfolder;         for(int i=fileName.length()-1; i>0; i--)         {             if((QString(fileName.at(i)) == QString("\\")) || (QString(fileName.at(i)) == QString("/")))             {                 subfolder = fileName.left(i);                 dir.mkpath(destinationFolder+"/"+subfolder);                 break;             }         }           QFile outFile(destinationFolder+"/"+fileName);         if(!outFile.open(QIODevice::WriteOnly))         {             file.close();             return false;         }         outFile.write(qUncompress(data));         outFile.close();     }       file.close();     return true; }