BaseX: A Base8/Base32/Base64 Encoder/Decoder in C

BaseX is a command-line tool for encoding and decoding files using the Base8, Base32, and Base64 formats. It provides a straightforward interface for transforming file content into these formats or decoding them back to their original state.

Features

• Encode files into Base8, Base32, or Base64 formats.
• Decode files from Base8, Base32, or Base64 formats.
• Supports binary file input and produces output via stdout.
• Returns nonzero error codes for invalid input during decoding.

Installation

To use BaseX, compile the source code with a C compiler using std C23:

mkdir build | clang -Iinclude -std=c23 src/*.c -o build/basex

Make sure that the base8.h, base32.h, and base64.h header files are in projectRoot/include, and source files are in projectRoot/src, or this command will not work.

Usage

basex [options] <format> <file>

Arguments

• <format>: The encoding/decoding format. Valid options are:
  • base8: Base8 (octal) encoding/decoding.
  • base32: Base32 encoding/decoding.
  • base64: Base64 encoding/decoding.
• <file>: The path to the file to encode or decode.

Options

• -d: Decode the input file.
• -h: Display the help message and usage instructions.

Examples

Encoding a File

To encode a file named input.txt in Base64:

basex base64 input.txt

Decoding a File

To decode a file named encoded.txt from Base32:

basex -d base32 encoded.txt

Displaying Help

basex -h

Error Handling

• If the input file is invalid or cannot be opened, an error message is printed to stderr.
• If decoding fails due to invalid input, the program exits with a nonzero error code.