System-Programming

This repository contains System Call and FUSE implementations on Linux.

• In System Call fork() and exit() system calls are modified for managing processes.
• In FUSE a read-only directory created which tidies HTML files of a website using Libtidy.

System Call Development

Requirements For System Call Project

   - Install Virtual Box (highly recommended in system call development process because of safety)
   - Download Lubuntu 14.04.5 LTS from http://cdimage.ubuntu.com/lubuntu/releases/14.04.5/release/
   - create your virtual machine and DON'T UPDATE it.
   - Install required packages with using this command : 
     - sudo apt-get update
     - sudo apt-get install manpages-dev g++ patch strace ltrace linux-headers-$(uname -r) linux-source kernel-package fakeroot libncurses5-dev libfuse-dev

Adding a System Call

   - move linux source archive file to desktop
     - cd Desktop
     - sudo mv /usr/src/linux-source-3.13.0/linux-source- 3.13.0.tar.bz2 linux-source-3.13.0.tar.bz2
   - and extract it
     - tar -xjvf linux-source-3.13.0.tar.bz2
   - enter linux source folder  cd linux-source-3.13.0

Write Your System Call

   - You can find the step by step project explanation in SystemCall/STEP_BY_STEP_REPORT.pdf report. 

Compile and Install New Kernel

   - Use make defconfig command to generate kernel configuration 
   - make-kpkg cleans the previous kernel compilations
   - Compile Command (It may take 30 minutes) : 
     - fakeroot make-kpkg --initrd --append-to-version=-custom kernel_image kernel_headers
   - You can find the kernel image and kernel header outputs in the desktop.
   - Install the new kernel : 
     - sudo dpkg -i linux-image-3.13...
     - sudo dpkg -i linux-headers-3.13...
     - sudo update-grub
     - sudo reboot( You can find the new kernel from advanced options )
   - Now you can test it.

Uninstall Compiled Kernel

   - sudo dpkg -r linux-image-3.13...custom
   - sudo dpkg -r linux-headers-3.13...custom

FUSE Development

INFORMATION

• This is a Website Read Only File System for users.
• Simply it does not allows write operations in it.
• Main purpose is giving tidied HTML files to users.
• In read operation code creates tidied output of HTML.

REQUIREMENTS

• First we need to install libtidy
• git clone git@github.com:htacg/tidy-html5.git
• cd {your-tidy-html5-directory}/build/cmake
• cmake ../.. -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/usr
• make
• sudo make install

USAGE

• Create a directory ( for example Website )
• In Website directory create html directory
• The other directories in website does not make sense.
• Move your .html files into html directory
• Go to out of your website.
• Create a directory named test
• Create a configuration file config.txt to make configuration
• For a true configuration change the config_file_path to your code directory
• Then compile using : gcc -I/usr/include/tidy myFuseSystem.c -o myFuse -Wall -ansi -W -std=c99 -g -ggdb -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -lfuse -ltidy
• Execute : ./myFuse -d website test
• Open another terminal and go to test/html directory
• Read the Html files using cat try.html
• Output is tidied.
• You can find all explanations and requirements in THIS report.