Zip Archives in C3

Overview

zip.c3l is a lightweight library for handling ZIP and ZIP64 archive files in C3. This package makes it easy to read and write ZIP files natively in C3, with a simple interface. It's especially useful for C3 projects that need basic ZIP archiving functionality without relying on external dependencies or heavy native bindings.

Features

• Read and extract files from ZIP archives.
• Extract AE-X encrypted ZIP entries.
• Create new ZIP archives and add files.
• Support ZIP and ZIP64 formats.
• C3 implementation without any external dependencies.

Installation

1. Add to your project: Clone or add zip.c3l as a submodule in your repository.

git submodule add https://github.com/konimarti/zip.c3l.git
git submodule update --init --recursive

2. Update project.json:

{
    "dependency-search-paths": [ "lib" ],
    "dependencies": [ "zip" ]
}

3. Import in your C3 code: Import the module where you need zip archive functionality:

import archive::zip;

Usage Examples

Read a ZIP archive

import archive::zip;
import std::io;

fn void main() => @pool()
{
    File f = file::open("archive.zip", "rb")!!;
    defer (void) f.close();

    ZipReader reader = zip::topen(&f)!!;
    io::printfn(reader);
}

Extract files to a folder

import archive::zip;

fn void main()
{
    File f = file::open("archive.zip", "rb")!!;
    defer (void) f.close();

    zip::extract(&f, "output/")!!;
}

Create a ZIP archive and add files

import archive::zip;

fn void main() => @pool()
{
    File f = file::open("archive.zip", "wb")!!;
    defer (void) f.close();

    ZipWriter w = zip::tcreate(&f)!!;
    w.write_buffer("document.txt", "Hello World!")!!;
    w.close();
}

Iterate over all files in a ZIP archive

import archive::zip;
import std::io;

fn void main() => @pool()
{
    File f = file::open("archive.zip", "rb")!!;
    defer (void) f.close();

    ZipReader reader = zip::topen(&f)!!;
    foreach (entry : reader)
    {
	    io::printn(entry.filename);
    }
}

API Reference

• fn void? zip::extract(InStream archive, String folder): Extract all files in zip archive to a directory.
• fn void? zip::archive(Path path, Path ref_path, OutStream output): Archive a file or folder to an output stream.

ZipReader

• fn ZipReader? zip::open(Allocator allocator, InStream archive): Open an existing zip archive for reading.
• fn ZipEntry? ZipReader.get(usz index) @operator([]): Get the entry at index.
• fn usz? ZipReader.len() @operator(len): Get number of entries.
• fn void ZipReader.free(): Free the resources.

ZipWriter

• fn ZipWriter? zip::create(Allocator allocator, OutStream output): Create a new zip archive for writing.
• fn ZipEntry? ZipWriter.write_buffer(String filename, char[] content, ZipCompressMethod method = COMPRESS_STORE): Add a file with the specified filename and content.
• fn void ZipWriter.close(): Close the zip writer and finalize the zip archive.
• fn void ZipWriter.free(): Free the resources.

ZipEntry

• fn LimitReader? ZipEntry.open_compressed(InStream archive): Return the compressed data of a specific entry as a readable stream.
• fn ExtractResult? ZipEntry.extract_to(OutStream output, InStream archive, bool verify_checksum = true): Extract a specific entry to an output stream.

Note that some functions that accept an allocator, often have an alternative using the temporary allocator.

Note for Windows user

Zip archive files should be openend in binary mode (either "rb+" or "wb+"). This ensures that fseek works correctly under Windows. 1.

License

MIT License.