CPM.cmake/README.md

CPM

CPM is a minimalistic package manager written in Cmake using find_package and FetchContent as a fallback to download non locally installed packages.

Usage

To add a new dependency to your project simply add the Projects target name, the git URL and the version. If the git tag for this version does not match the pattern v$VERSION, then the exact branch or tag can be specified with the GIT_TAG argument. CMake options can also be supplied with the package.

cmake_minimum_required(VERSION 3.14 FATAL_ERROR)

project(MyProject)

# add dependencies
include(${CMAKE_CURRENT_SOURCE_DIR}/cmake/CPM.cmake)

CPMAddPackage(
  NAME LarsParser
  GIT_REPOSITORY https://github.com/TheLartians/Parser.git
  VERSION 1.8
  GIT_TAG v1.8 # optional, as already defined by VERSION
  OPTIONS      # used to set CMake options in the inner package
    "LARS_PARSER_BUILD_GLUE_EXTENSION ON"
)

# add executable
set (CMAKE_CXX_STANDARD 17)
add_executable(my-project my-project.cpp)
target_link_libraries(my-project LarsParser)

Adding CPM

To add CPM to your current project, simply include add cmake/CPM.cmake to your projects cmake directory. The command below will perform this automatically.

wget -O cmake/CPM.cmake https://raw.githubusercontent.com/TheLartians/CPM/master/cmake/CPM.cmake

Supported packages

Basically any project that you can add via add_subdirectory should work with CPM.

Options

If you set the CMake option CPM_REMOTE_PACKAGES_ONLY to On, packages will always be fetched via the URL. Setting CPM_LOCAL_PACKAGES_ONLY to On will only add packages via find_package.

Advantages

• Small repos CPM takes care of package dependencies, allowing programmers to focus on creating small well-tested frameworks.
• Cross-Plattform CPM adds projects via add_subdirectory, which is compatible with all cmake toolchains and generators.
• Reproducable builds By using versioning via git tags it is ensured that a project will always be in the same state everywhere.
• No installation required No need to install any third-party package managers. Just copy the files from the CMake directory and you're good to go.

Limitations

• First version used In diamond-shaped dependency graphs (e.g. A depends on C(v1.1) and A depends on B depends on C(v1.2)) the first added dependency will be used (in this case C@1.1).
• No auto-update To update a dependency, version numbers or git tags in the cmake scripts must be adapted manually.