Template project for building a plugin (shared lib) with Conan v2 and CMake

Intro

This is a template for building a C++ plugin as a shared-lib/DLL/CFBundle. It uses Conan for dependencies and CMake as the build generator. It's intended to show best practices for using modern (as of 2024) cmake, 3.28 or later, and Conan v2.

It uses the new-for-2024 conan-cmake integration, where cmake calls conan to install the dependencies and then configure the build. A copy of that integration is included in this repo as conan_provider.cmake.

Build

To build the plugin, use ./build.sh. This runs cmake --preset Release to configure, and then cmake --build --preset Release to do the build using the configured build tool (cmake's default is Makefiles).

The configure step invokes conan to build/install the dependencies. In this template, I've used the spdlog logging framework based on fmt as a sample dependency, just to show how the system works.

The CMakePresets.json default preset is configured to include the conan-cmake provider which makes cmake invoke conan to install the dependencies and pass along all the necessary generator, compiler info, etc.

Notes

• To use a different generator, e.g. "Ninja Multi-Config":

  cmake --preset default -G "Ninja Multi-Config"
  cmake --build --preset default --config Debug
  cmake --build --preset default --config Release

  (this is in build-ninja.sh)

• To do a build with a manual conan install invocation, do it like this:

  conan install . --build=missing
  cmake --preset conan-release # or on Windows, cmake --preset conan-default, because VS is multi-config
  cmake --build --preset conan-release

  and to build in debug mode, do this:

  conan install . -s build_type=Debug --build=missing
  cmake --preset conan-debug # or on Windows, cmake --preset conan-default
  cmake --build --preset conan-debug

• To do a multi-config build with manual conan install, do this:

  conan install . --build=missing -c tools.cmake.cmaketoolchain:generator="Ninja Multi-Config" -s build_type=Debug
  conan install . --build=missing -c tools.cmake.cmaketoolchain:generator="Ninja Multi-Config"
  cmake --preset conan-default
  cmake --build --preset conan-debug
  cmake --build --preset conan-release
  

  (this is in build-conan-ninja.sh)

• To do a clean build, remove the build directory, and CMakeUserPresets.json. If you don't remove the presets file the build will fail because CMakeUserPresets.json, which is generated by conan, refers to files in build. The build.sh script will remove that preset file if build doesn't exist, to prevent that error.