rhx / swiftglib

A Swift wrapper around glib-2.x that is largely auto-generated from gobject-introspection

SwiftGLib

A Swift wrapper around glib-2.x that is largely auto-generated from gobject-introspection. For up to date (auto-generated) reference documentation, see https://rhx.github.io/SwiftGLib/

What is new?

• SwiftGLib 2.73 introduces typed convenience wrappers for GLib collection types such as GArray, GByteArray, GList, GSList, and GSequence.

• Version 15 of gir2swift provides a Package Manager Plugin. This requires Swift 5.6 or higher (older versions can be used via the swift52 branch).

Prerequisites

Swift 5.7 or higher

To build, download Swift from https://swift.org/download/ -- if you are using macOS, make sure you have the command line tools installed as well). Test that your compiler works using swift --version, which should give you something like

$ swift --version
swift-driver version: 1.90.11.1 Apple Swift version 5.10 (swiftlang-5.10.0.13 clang-1500.3.9.4)
Target: arm64-apple-macosx14.0

on macOS, or on Linux you should get something like:

$ swift --version
Swift version 5.10 (swift-5.10-RELEASE)
Target: x86_64-unknown-linux-gnu

GLib 2.56 or higher

These Swift wrappers have been tested with glib-2.56, 2.58, 2.60, 2.62, 2.64, 2.66, 2.68, 2.70, 2.72, 2.73, 2.74, 2.76, 2.78, and 2.80. They should work with higher versions, but YMMV. Also make sure you have gobject-introspection and its .gir files installed.

Linux

Ubuntu

On Ubuntu 18.04, 20.04, and 22.04 you can use the glib that comes with the distribution. Just install with the apt package manager:

sudo apt update
sudo apt install libglib2.0-dev glib-networking gobject-introspection libgirepository1.0-dev libxml2-dev jq

Fedora

On Fedora 29, you can use the gtk that comes with the distribution. Just install with the dnf package manager:

sudo dnf install glib2-devel gobject-introspection-devel libxml2-devel jq

macOS

On macOS, you can install glib using HomeBrew (for setup instructions, see http://brew.sh):

brew update
brew install glib glib-networking gobject-introspection pkg-config jq

Usage

Normally, you don't build this package directly (but for testing you can - see 'Building' below). Instead you need to embed SwiftGLib into your own project using the Swift Package Manager. After installing the prerequisites (see 'Prerequisites' below), add SwiftGLib as a dependency to your Package.swift file, e.g.:

// swift-tools-version:5.7

import PackageDescription

let package = Package(name: "MyPackage",
    dependencies: [
        .package(url: "https://github.com/rhx/gir2swift.git", branch: "main"),
        .package(url: "https://github.com/rhx/SwiftGLib.git", branch: "main"),
    ],    
    targets: [
        .target(name: "MyPackage",
                dependencies: [
                    .product(name: "GLib", package: "SwiftGLib")
                ]
        )
    ]
)

Building

Normally, you don't build this package directly, but you embed it into your own project (see 'Usage' above). However, you can build and test this module separately to ensure that everything works. Make sure you have all the prerequisites installed (see above). After that, you can simply clone this repository and build the command line executable (be patient, this will download all the required dependencies and take a while to compile) using

git clone https://github.com/rhx/SwiftGLib.git
cd SwiftGLib
swift build
swift test

Documentation

You can generate documentation using the DocC plugin. To preview documentation matching your local installation, simply run

swift package --disable-sandbox preview-documentation

then navigate to the URL shown for the local preview server. Make sure you have JavaScript enabled in your browser.

Alternatively, you can create static documentation using jazzy. Make sure you have sourcekitten and jazzy installed, e.g. on macOS (x86_64):

brew install ruby sourcekitten
/usr/local/opt/ruby/bin/gem install jazzy
./generate-jazzy.sh

Troubleshooting

Here are some common errors you might encounter and how to fix them.

Missing .gir Files

If you get an error such as

Girs located at
Cannot open '/GLib-2.0.gir': No such file or directory

Make sure that you have the relevant gobject-introspection packages installed (as per the Pre-requisites section), including their .gir and .pc files.

Old Swift toolchain or Xcode

If, when you run swift build, you get a Segmentation fault (core dumped) or circular dependency error such as

warning: circular dependency detected while parsing pangocairo: harfbuzz -> freetype2 -> harfbuzz

this probably means that your Swift toolchain is too old, particularly on Linux. Make sure the latest toolchain is the one that is found when you run the Swift compiler (see above).

If you get an older version, make sure that the right version of the swift compiler is found first in your PATH. On macOS, use xcode-select to select and install the latest version, e.g.:

sudo xcode-select -s /Applications/Xcode.app
xcode-select --install

swiftglib's Issues

Example Usage?

I am investigating whether SwiftGLib would be appropriate for writing a Swift wrapper library of the Apache Arrow GLib library. I don't see any example usage in the docs or in the tests to help me figure out how this might be done. Are there any example projects that are using SwiftGLib that might be used as reference?

Building on Fedora 39 fails: GLib.swift:386:74: error: cannot find type 'utimbuf' in scope

I've attempted both using gtk3-devel and gtk4-devel, but no dice.

As a last resort I also attempted installing all developer packages, but that didn't help either.

$ sudo dnf group install "C Development Tools and Libraries" "Development Tools"

Swift is version 5.8.1:

$ swift --version
Swift version 5.8.1 (swift-5.8.1-RELEASE)
Target: x86_64-unknown-linux-gnu

Here's my Package.swift:
Package.swift.txt

Here's the full log:
buildlog.txt

iOS Build

Is a port to iOS possible with glib? A compiled .framework would be the goal here.

Errors building on Fedora 40

I just updated my system to Fedora 40 (On ARM64 architecture)

On my project based on SwiftGtk (Gtk 3), I deleted the .build directory and the Package.resolved file.

Then I ran swift build, but there are some error messages, and the package is not built:

Building for debugging...
/home/lalo/codigos/chickenpos/.build/plugins/outputs/swiftglib/GLib/gir2swift-plugin/gir2swift-generated/GLib/GLib-2.0-functions.swift:6285:18: error: 'g_open' is unavailable: Variadic function is unavailable
    let result = g_open(filename, gint(flags), gint(mode))
                 ^~~~~~
CGLib.g_open:2:13: note: 'g_open' has been explicitly marked unavailable here
public func g_open(_: UnsafePointer<CChar>, _: Int32, _ varargs: Any...) -> Int32
            ^
/home/lalo/codigos/chickenpos/.build/plugins/outputs/swiftglib/GLib/gir2swift-plugin/gir2swift-generated/GLib/GLib-2.0-functions.swift:7620:18: error: cannot find 'g_set_prgname_once' in scope
    let result = g_set_prgname_once(prgname)
                 ^~~~~~~~~~~~~~~~~~
error: emit-module command failed with exit code 1 (use -v to see invocation)
/home/lalo/codigos/chickenpos/.build/plugins/outputs/swiftglib/GLib/gir2swift-plugin/gir2swift-generated/GLib/GLib-2.0-functions.swift:6285:18: error: 'g_open' is unavailable: Variadic function is unavailable
    let result = g_open(filename, gint(flags), gint(mode))
                 ^~~~~~
CGLib.g_open:2:13: note: 'g_open' has been explicitly marked unavailable here
public func g_open(_: UnsafePointer<CChar>, _: Int32, _ varargs: Any...) -> Int32
            ^
/home/lalo/codigos/chickenpos/.build/plugins/outputs/swiftglib/GLib/gir2swift-plugin/gir2swift-generated/GLib/GLib-2.0-functions.swift:7620:18: error: cannot find 'g_set_prgname_once' in scope
    let result = g_set_prgname_once(prgname)
                 ^~~~~~~~~~~~~~~~~~

Regression: Can no longer iterate over a ListRef using for-in loop

I have some code which was working previously, where I iterated over a ListRef in a for-in loop, but it stopped working when I upgraded my system from Fedora 37 to 38.

ListRef was conforming to the Sequence protocol, and that was very convenient, but it seems not the case since I upgraded my Operating System.

This is a minimal code example that emits an error message on Fedora 38, but it still works OK on Fedora 37:

func iterateList(list: ListRef){
    for item in list {
        print ("item")
    }
}

This is the error message I get when I try to build the project:

error: for-in loop requires 'ListRef' to conform to 'Sequence'
    for item in list {
                ^~~~

I have two computers, one with Fedora 37 (x86-64) and the other one with Fedora 38 (aarch64). This bug is only present on the one with Fedora 38.

I'm using swift-lang package from Fedora repos in both machines. swift-lang version is 5.8.

The difference seems to be the glib2 package, which is version 2.76 on Fedora 38, while Fedora 37 have version 2.74.