zig build for mosquitto

Cross compile mosquitto using zig build (tested with ziglang 0.14.0).

• produce static executables
• support for TLS (with an option to disable it if it is not needed)
• bridge enabled
• no websocket support
• no systemd support (e.g. SDNotify isn't enabled)

Build Pre-requisites

• ziglang 0.14.0
• nfpm (to build the linux packages)
• wget (used to download the mosquitto source code)

Building

1. Clone the project

   git clone https://github.com/thin-edge/zig-mosquitto
   cd zig-mosquitto

2. Checkout/download the mosquitto source code

   just checkout-mosquitto

   Or you can specify the mosquitto version by setting the VERSION environment variable.

   VERSION=2.0.21 just checkout-mosquitto

3. Build all targets

   just build-all

   Or specify the VERSION environment variable.

   VERSION=2.0.21 just build-all

   If you don't want to include TLS, then you can run:

   just build-notls-all

4. Use the build linux packages under the dist/ folder

   ls -l dist/
   
   # Using DNF (Fedora, RHEL, AmazonLinux)
   dnf install tedge-mosquitto*.rpm
   
   # Using Debian/Ubuntu
   apt-get install tedge-mosquitto*.deb

Building a single target

If you don't want to build for all of the targets, then you can build using

The compiled mosquitto binary will be created under ./zig-out/mosquitto, however it will only be the binary from the last build.

With TLS

just build x86_64-linux-musl amd64

just build aarch64-linux-musl arm64

just build arm-linux-musleabihf arm7

just build arm-linux-musleabi arm5

just build riscv64-linux-musl riscv64

Without TLS

just build-notls x86_64-linux-musl amd64

just build-notls aarch64-linux-musl arm64

just build-notls arm-linux-musleabihf arm7

just build-notls arm-linux-musleabi arm5

just build-notls riscv64-linux-musl riscv64

# Clone: mainly a build.zig file
$ git clone https://github.com/thin-edge/zig-mosquitto
$ cd zig-mosquitto

# The build expect a mosquitto sub-directory with mosquitto sources 
$ wget https://mosquitto.org/files/source/mosquitto-2.0.18.tar.gz
$ tar -xzf mosquitto-2.0.18.tar.gz
$ ln -s mosquitto-2.0.18 mosquitto

# Compile with appropriate target
$ zig build -Doptimize=ReleaseSmall -Dtarget=aarch64-linux-musl
$ ls -l zig-out/bin/mosquitto
-rwxrwxr-x 1 didier didier 209200 juin  19 22:00 zig-out/bin/mosquitto
$ file zig-out/bin/mosquitto
zig-out/bin/mosquitto: ELF 64-bit LSB executable, ARM aarch64, version 1 (SYSV), statically linked, stripped

TODO

The following items are still yet to be addressed/fixed:

• Support for other init systems like OpenRC, SysVInit, s6-overlay