daminals / fliki

fliki on-the-fly operation to implement patching onto diff files

Fliki

fliki is a command line function that reads a diff file and an input file from stdin, and applies a patch using the diff file to read the new output to stdout. The function is based on the "patch" utility, and is written in C.

a diff file is a difference file, or a file specifying the differences between two files. You can create your own diff file by running the linux function diff file1 file2 in your terminal

It uses an "On-the-fly" operation style, where files are processed character by character. It breaks up the diff files into 'hunks', or sections of the diff file characterized by a change mode, append mode, and delete mode.

It processes hunks through their headers in hunk_next. Then the hunk is looped through with hunk_getc, which returns the proper character to append or delete in the output file, and returns EOS (end of section) when a hunk is completed. Lastly, patch is designated as the function which will take in a diff and input file and print the appropriate characters to the output, successfully applying all changes defined in the diff file to the input.

Argument validity is checked in the valid_args function, and reads the three flags accepted by fliki, -h (help), -q (quiet mode | no errors printed), -n (no patch mode | dry run of program without writing to stdout)

Installation

To use Fliki, you will need to have C installed on your computer. You can download the source code from the GitHub repository, or you can clone the repository using the following command:

git clone https://github.com/daminals/fliki.git

Once you have downloaded or cloned the repository, navigate to the directory and run the following command to compile the code:

make all

This will create an executable file called "fliki". You can then run the program by typing:

./bin/fliki

Usage

To use Fliki, you will need to provide a diff file and an input file. These files can be passed to the program using stdin.

Here is an example of how to use Fliki:

cat input.txt | fliki file.diff > output.out

This command will read the contents of the input.txt file, apply the patch contained in the file.diff file, and output the result to the output.out file.

Testing

This project uses the Criterion testing framework.

Test cases can be run with

make clean all && ./bin/fliki_tests

They are also attached to a github action and run as a CI/CD workflow upon every commit to ensure proper functionality.