Gtk-OSX

This project along with gtk-mac-bundler and gtk-mac-integration aims to simplify building MacOS application bundles for Gtk+-based applications. Gtk-OSX provides modulesets, patches, and jhbuild enhancements for building Gtk+ applications on your Mac. Unlike "package manager" style systems like MacPorts or Homebrew, Gtk-OSX installs products into user-configurable "silo" subdirectories that stand on their own, making it easy to have multiple independent installations of the Gtk+ stack and other dependencies to accommodate the requirements of different applications. The build environment created by Gtk-OSX is suitable for development of Gnome libraries and Gtk+-based applications on MacOS; indeed the author has been using it for just that purpose for almost 10 years.

Modulesets

There are 3 modulesets. You can select the one which most suits you by adding the line moduleset="https://gitlab.gnome.org/GNOME/gtk-osx/raw/master/modulesets-stable/gtk-osx.modules"

to your ~/.jhbuildrc-custom, replacing "modulesets-stable" (the default) with

• modulesets-stable: The default, all tarball-based released sources.
• modulesets: Sources from VCS repositories when that's available, with stable release revisions set for each module.
• modulesets-unstable: The bleeding edge modulesets, pulled from VCS repositories with no release revisions.

Customization

Jhbuild has a hook that opens a special file ~/.jhbuildrc (the name and path can be overridden with the -f command-line parameter). Gtk-OSX provides a file intended to be installed as ~/.jhbuildrc that configures the build parameters according to the version of MacOS that you're running or that you intend to target, i.e. MACOS_DEPLOYMENT_TARGET. That file, jhbuildrc-gtk-osx, includes it's own hook to load a file named ~/.jhbuildrc-custom (not overrideable, sorry). This second rc file is for local customization, including the usual things contemplated by the jhbuild developers for the configuration file. While Gtk-OSX provides a sample file with extensive comments explaining possible options, users should in no way feel constrained by those comments. The file is Python and is loaded and executed just as is the rest of jhbuild so there are huge opportunities for further customization.

MacOS Version Support

We tried for a long time to maintain compatibility with Mac OS X 10.4 (Tiger), but the core Gnome projects decided at some point that this wasn't reasonable; Apple's changes to MacOS, particularly with the dropping of PPC support in Mac OS X 10.6 and the impending removal of 32-bit support in 10.15 mean that it's not really feasible to both keep up with changes in Gnome and in MacOS and also to support older versions of MacOS.

The current policy is that we'll support whatever version of MacOS was released 5 years previously. In practice older systems will continue to work as long as Apple didn't break anything between that older system and the 5-year-old release, but we'll periodically and without notice clean up ifdefs and such supporting older systems. If you insist on using an old system, check out the last version of Gtk-OSX that supports it and never pull again. Make sure that your configuration is set up to use local modulesets, the ones in the public repositories are frequently upgraded and are unlikely to work on obsolete versions of MacOS.

Python

Gnome is transitioning to requiring Python3.2+ for just about everything else. In particular they have adopted a new build system, meson, that requires Python3 and has dropped support for autotools builds in several of its core packages.

Apple provided Python3 in Mac OS X 10.6 and dropped it in 10.7, so we need to arrange for Python 3 to be available for jhbuild to build meson files with as well as meson itself. Gtk-OSX takes care of that at installation. It relies on two Python standard packages, Pipenv and pyenv. In combination they create a Python3 virtual environment and populate it with to required dependencies, the afore-mentioned meson and six, a python 2/3 compatibility library used by gtk-doc.

Python Configuration

gtk-osx-setup.sh uses several environment variables to control where it puts things. Override the defaults by setting the corresponding variable in the environment before running gtk-osx-setup.sh.

• DEVROOT default: $HOME Base directory
• DEVPREFIX default: $DEVROOT/.new_local Prefix for jhbuild tools
• PYTHONUSERBASE default: $DEVROOT/.new_local Location where PIP installs packages when --user is given as an option; new-setup.sh uses --user when invoking pip.
• DEV_SRC_ROOT default: $DEVROOT/Source Location of pyenv and jhbuild sources
• PYENV_ROOT default: $DEV_SRC_ROOT/pyenv Prefix for pyenv's sources and virtual environments.
• PIP_CONFIG_DIR default: $HOME/.config/pip Pip's configuration, see the PIP documentation.

PYTHONUSERBASE, PYENV_ROOT, and PIP_CONFIG_DIR are actually specified by PIP and PYENV. Pipenv and pyenv have other control environment variables, consult their documentation for more information.

gtk-osx-setup.sh will create several shell-script and configuration files, but it will not overwrite any that already exist so it's safe to customize your setup after running it. The files are:

• $DEVPREFIX/etc/Pipfile Configures the python version and installed packages.
• $DEVPREFIX/etc/pipenv-env Environment variables for pipenv-controlled virtual environment.
• $DEVPREFIX/bin/jhbuild Shell script to run jhbuild inside a pipenv-controlled virtual environment using the above Pipfile and pipenv environment file.
• $DEVPREFIX/libexec/run_jhbuild.py Python file replacing the jhbuild executable provided by jhbuild itself. Called from the jhbuild shell script.

gtk-osx-setup.sh will also copy /usr/bin/bash to $DEVPREFIX/bin and jhbuildrc-gtk-osx will set $SHELL to that path to work around SIP.

The pipenv control file sets Python3.6 as its required version, and gtk-osx-setup.sh will create a pyenv virtual environment for that. If you don't already have Python3.6 in your $PATH it will offer to install the latest Python3.6 release for you.

Before you build there's one manual step needed: Python3 insists on setting LINKFORSHARED: -Wl,stack_size,1000000 -framework CoreFoundation even though stack_size is allowed only when compiling executables. It's in $PYENV_ROOT/versions/3.6.x/lib/python3.6/_sysconfigdata_m-darwin.py. Open that file with your programming editor and find and change it to LINKFORSHARED: -framework CoreFoundation.

Bootstrapping

Unlike previous versions of gtk-osx-build-setup.sh, gtk-osx-setup.sh does not copy the Gtk-OSX boostrap moduleset over the jhbuild one. Instead, jhbuildrc provides a new command

jhbuild bootstrap-gtk-osx

This command will by default load the bootstrap.modules from gtk-osx's Gitlab repository. If use_local_modules is true (default is false, override it in jhbuildrc-custom) and a file named bootstrap.modules exists in the same directory as the moduleset you've told jhbuild to use (set with moduleset = in jhbuildrc-custom or the -m option to jhbuild) it will build that. This allows you to have a custom bootstrap.modules for your project.

If you set use_local_modules to true and set modulesets_dir = to a valid path containing a file named bootstrap.modules then bootstrap-gtk-osx will build that moduleset instead.

Note that in order to actually work the bootstrap.modules moduleset file must contain a meta-module named meta-bootstrap that depends on all of the modules that you want to build.

Build Problems

I encountered two build problems while creating this:

• gdk-pixbuf builds its modules as shared libraries instead of loadable modules so gdk-pixbuf-query-loaders can't find them. Stop the build, rename them (they're in $PREFIX/lib/gdk-pixbuf/2.10.0/loaders) from e.g. libpixbufloader-png.dylib to libpixbufloader-png.so and rerun gdk-pixbuf-query-loaders --update.

• Pango's meson passes a bogus -framework CoreFoundation ApplicationServices arg at the end of the g-ir-scanner command, and that fails. I couldn't figure out where it came from so I wound up editing meson.build in the build directory and removing the argument from the command.