LibGit2 on iOS

Similar to our LLVM-On-iOS project and actually thank to the experience from that project, we develop this project to provide scripts and YAML pipeline to build LibGit2 and its dependencies (OpenSSL, PCRE and LibSSH2) on Azure DevOps (a.k.a. VSTS) as XCFrameworks that could be easily embedded in Xcode iOS/Mac Catalyst project.

Building

If you want to build the frameworks on your own machine, simply execute the script

build-libgit2-framework.sh

at the root of this repository. See here for our CI builds on Azure DevOps.

A tip for Windows user: Instead of using swift package compute-checksum, one can also compute checksum with

CertUtil -hashfile Clibgit2.xcframework.zip SHA256

Integration

Method 0: Interoperate Swift, C/C++ and Objective-C via bridging header as described in our LLVM-On-iOS project. You can use libgit2.xcframework if you want to use our prebuilt.

Method 1: You can download our prebuilt XCFramework, extract and add it directly to your Xcode iOS app project. For this method, you will need the Clibgit2.xcframework which exposes the module to Swift. Then simply

import Clibgit2

and then use the libgit2 C API directly. The built XCFramework is also released as a Swift Package at https://github.com/light-tech/Clibgit2. But since libgit2 is a C library, be ready to write some not-very-Swift-y Swift code. See also the official documentation.

Method 2: Our recommended way is to use the Swift Package available on the spm branch of our fork of SwiftGit2. Basically, SwiftGit2 takes care of the not-very-Swift-y Swift code in method 1. See the screenshots in our example app below.

Example

To test, you can get our iOS example app project by cloning

git clone https://github.com/light-tech/SwiftGit2-SampleApp.git

Why?

The first thing that might have come to your mind is:

Why another work on libgit2? Didn't we already have SwiftGit2?

The reasons:

Contrary to the first impression, SwiftGit2 currently doesn't compiled for iOS unless one reverts back to an earlier version. The reason is that libgit2 now depends on libpcre which is only supplied in Xcode's MacOS SDK but not iOS SDK; hence we will run into missing symbols pcre_***** when using it in an iOS app.
SwiftGit2 isn't very actively maintained. It still uses the older fat binary (which cannot support MacOS, Mac Catalyst and iPhone Simulator simultaneously since all 3 have the same underlying CPU architecture x86_64 but different ABI) instead of switching to XCFramework.
We are only aware of this blog post after doing this work. And the post doesn't build libpcre which is necessary for many Git features on iOS.
We do not intend to replace SwiftGit2 but to extract and update its outdated building scripts.

License