git-bash-pacman

The script convert_git_bash.sh and its supporting file convert_git_bash_functions attempt to convert your git bash installation without pacman into an installation that has pacman so you can install packages.

Warning

This is very much unsupported by anyone upstream, and a pretty ridiculous thing to do. Also, this works for my usecase.

It is highly recommended to have a usecase which does not use UNC paths in any capacity (such as git bash being on a remote directory or executing the scripts from the same), such as \\?\C:\example\path\here or \\my_host\example\path\here. Not only will network paths likely be slow (as in the latter case), it is untested whether or not it will even work.

Your mileage will vary, and I don't have any fuel for you.

Usage

This has been tested against the 64-bit version of Git for Windows as installed by its standalone installer for system-wide use.

Retrieve the convert_git_bash.sh and convert_git_bash_functions files, put them somewhere that git bash has access to (your home directory is good enough).

Then, run the git bash terminal as admin. This is required for system-wide installs, unless your user has read/write access to all paths underneath the msys root for git. If you have a user installation of Git for Windows, this might work without admin, but has not been tested.

The following environment variables modify execution, with the following defaults:

CHECK_ADMIN=yes
CONFIRM_BEFORE_PROCEEDING=yes

DOWNLOAD_MSYS=check
UNTAR=check
UPDATE_GPG=check
FIX_BROKEN_PACKAGES=check
UPDATE_MSYS2=check

These environment variables also are in the same order as the general steps, so these can be modified for troubleshooting purposes.

Discussion

This is a ridiculous way to work around downloading the msys2 installer or grabbing the Git for Windows SDK to get a more fully-featured shell environment.

However, some things to note:

1. You probably already have a Git for Windows installation if you use git on Windows.
2. You can reuse the installation instead of setting everything up again.
3. You can shed tears whenever it automatically updates, because that will probably break something.

In the grand scheme of the Machine God, it's probably okay for if you only need a couple of packages.

Obviously, I don't recommend relying on this for any critical usecases, such as making sure your pacemaker software builds or your pizza gets delivered on time. In other usecases, it's likely decent if you have the motivation to fix random happenstances that come your way.

As an aside, we do just grab the msys2 distribution tarball from upstream, and it extracts with the default msys2-git distribution. You could just use that.

I wanted to retrieve the specific packages I needed, like pacman and its supporting packages, but I couldn't find anything to extract this newfangled .zst file type so I could just grab the exact packages I needed (not even 7zip, which extracts everything, so I am led to believe .zst is just something that doesn't exist), so you could just use that, but that'd be less complicated. That would have been far more hacky, so it's probably better that didn't work.

License

See COPYING.txt. It's AGPL (v3!). If you can figure out a way to do network interaction with this program such that you're required to distribute your modifications and show me, I'll be impressed and may or may not send you 10 USD.