PunyLinux

Build automation (powered by Ruby & Rake) for a very minimal Linux system.

• Package Management
  • Aquire package sources (packages defined with DSL in files within pkg/)
    • Optionally verify package checksum
      • Download/Write the checksum to file
      • Verify with sha256sum
    • Optionally verify package sources by signature
      • Download/Write the signature to file
      • Verify with gpg
  • Decompress package sources
  • Build package sources
  • Install packages
• Image Management
  • Generate LINUX image
  • Generate ISOLINUX image

Install

• Clone this project
• Install dependencies
• Change into the project directory
• Run rake

Dependencies

• Ruby (tested on ruby 2.6.3p62)
• cUrl
• tar

Build Automation

You must install any development dependencies required to build all packages, such as:

• make
• cmake
• ninja
• meson
• etc.

Compressors

Since we are simply using tar -xf to decompress archives, simply install any compressor you would like to support:

• gzip
• xz
• etc.

Image Generation

• syslinux
• cdrkit

Usage

Tasks

View all tasks with:

rake -T

To view every single file to be generated, use:

rake -T -A

Package Management

Define any packages you would like to include within pkg/ and run rake pkg.
All package sources will be aquired, optionally checksummed and verified by signature.
Each package will then be built and installed into the build/root/os/ directory.

Packages are defined similarly to Rake files; within it's own Ruby DSL:

name      :package_name                                   # Package name
version   '1.2.3'                                         # Package version
archive   "https://example.org/#{name}-#{version}.tar.gz" # Archive source
signature "#{archive}.sig"                                # GPG signature source
checksum  "#{archive}.sha256"                             # Checksum source
files     %W(/bin/#{name} /etc/#{name}/config)            # Package install files


# on_check { |package| ... }                              # Callback to check this package's checksum
# on_verify { |package| ... }                             # Callback to verify this package's signature

on_build do |package|                                     # Callback to build this package
  sh <<~EOS
    cd '#{package.build_path}'
    ./configure
    make
  EOS
end

on_install do |package|                                   # Callback to install this package
  sh <<~EOS
    cd '#{package.build_path}'
    make DESTDIR'#{paths.os_root}' install
  EOS
end

Sources

Sources given for archive, signature, and checksum can be URI's or the contents of the source. Paths can be given with the file:// URI scheme.

Callbacks

When callbacks are not defined on a package they will not be run, with the exception of on_check and on_verify. These are only called if their respective sources are also defined in the specification. If they are defined, they are called instead of the default functionality.

Required Properties

The only required properties are name, version, and archive.

If there is an on_install callback defined, it is highly advised to properly define the files list, as this is what hooks the package into the Rake task dependency graph.

The list of files defined on the package are the paths that will be installed onto a system when the package is installed, relative to the system (i.e. root - /).

Linux Package

Only one package is required and it must be named linux and it must generate the following kernel:

build/root/os/boot/vmlinuz

Image Management

An ISO9660 image can be generated from the resulting Linux root directory.

This processes generates an initial ramdisk (initrd), archived with cpio and compressed. We then use ISOLINUX as a bootloader to load our kernel (built from the linux package). The kernel then loads the initial ramdisk into memory as the root device using initramfs and loads /sbin/init.

As an example, PunyLinux is shipped with a BusyBox package specification which includes Linux core utilities, including a simple init system. This package specification can be replaced/removed as it is not a required package.

Customization

Build configuration and paths can be setup by editing Rakefile

Tasks

The Rakefile loads all tasks/**/*.{rake,rb} files and you can freely edit these files or add your own.

File System

Paths under fs/ will be synced into the build/root/os/ directory when building, any of which can be freely modified.

If sticking with BusyBox, the init system runs etc/init.d/rcS after taking control. This is currently our initialization script.

Bootloader

ISOLINUX can be configured by editing src/isolinux.cfg. This includes the kernel command line options.

Note that you probably don't want to mess with initrd, rdinit, or root as this is what causes initramfs to take over using the generated initial ramdisk.

Contributing

1. Fork it (https://github.com/RyanScottLewis/punylinux/fork)
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Contributors

• Ryan Scott Lewis - creator and maintainer