cmake-conan

CMake wrapper for the Conan C and C++ package manager.

This cmake module allows to launch conan install from cmake.

The branches in this repo are:

• develop: PR are merged to this branch. Latest state of development
• master: Latest release
• tagged releases: https://github.com/conan-io/cmake-conan/releases.

You probably want to use a tagged release to ensure controlled upgrades.

You can just clone or grab the conan.cmake file and put in in your project. Or it can be used in this way. Note the v0.15 tag in the URL, change it to point to your desired release:

cmake_minimum_required(VERSION 2.8)
project(FormatOutput CXX)

# Download automatically, you can also just copy the conan.cmake file
if(NOT EXISTS "${CMAKE_BINARY_DIR}/conan.cmake")
   message(STATUS "Downloading conan.cmake from https://github.com/conan-io/cmake-conan")
   file(DOWNLOAD "https://github.com/conan-io/cmake-conan/raw/v0.15/conan.cmake"
                 "${CMAKE_BINARY_DIR}/conan.cmake" 
                 TLS_VERIFY ON)
endif()

include(${CMAKE_BINARY_DIR}/conan.cmake)

conan_cmake_run(REQUIRES fmt/6.1.2
                BASIC_SETUP 
                BUILD missing)

add_executable(main main.cpp)
target_link_libraries(main ${CONAN_LIBS})

conan_cmake_run() options

REQUIRES, OPTIONS

conan_cmake_run(REQUIRES fmt/1.9.4
                         cgal/5.0.2
                OPTIONS Pkg:shared=True
                        OtherPkg:option=value
                )

Define requirements and their options. These values are written to a temporary conanfile.py. If you need more advanced functionality, like conditional requirements, you can define your own conanfile.txt or conanfile.py and provide it with the CONANFILE argument

CMAKE_TARGETS

If you want to use targets, you could do:

include(conan.cmake)
conan_cmake_run(REQUIRES fmt/1.9.4
                BASIC_SETUP CMAKE_TARGETS
                BUILD missing)

add_executable(main main.cpp)
target_link_libraries(main CONAN_PKG::fmt)

This will do a conan_basic_setup(TARGETS) for modern CMake targets definition.

CONANFILE

If you want to use your own conanfile.txt or conanfile.py instead of generating a temporary one, you could do:

include(conan.cmake)
conan_cmake_run(CONANFILE conanfile.txt  # or relative build/conanfile.txt
                BASIC_SETUP CMAKE_TARGETS
                BUILD missing)

The resolution of the path will be relative to the root CMakeLists.txt file.

KEEP_RPATHS

include(conan.cmake)
conan_cmake_run(CONANFILE conanfile.txt
                BASIC_SETUP KEEP_RPATHS)

NO_OUTPUT_DIRS

include(conan.cmake)
conan_cmake_run(CONANFILE conanfile.txt
                BASIC_SETUP NO_OUTPUT_DIRS)

Pass to conan_basic_setup(NO_OUTPUT_DIRS) so conanbuildinfo.cmake does not change the output directories (lib, bin).

ARCH

include(conan.cmake)
conan_cmake_run(ARCH armv7)

Use it to override the architecture detection and force to call conan with the provided one. The architecture should exist in settings.yml.

BUILD_TYPE

include(conan.cmake)
conan_cmake_run(BUILD_TYPE "None")

Use it to override the build_type detection and force to call conan with the provided one. The build type should exist in settings.yml.

CONFIGURATION_TYPES

include(conan.cmake)
conan_cmake_run(CONFIGURATION_TYPES "Release;Debug;RelWithDebInfo")

Use it to set the different configurations when using multi-configuration generators. The default configurations used for multi-configuration generators are Debug and Release if the argument CONFIGURATION_TYPES is not specified The build types passed through this argument should exist in settings.yml.

PROFILE

include(conan.cmake)
conan_cmake_run(PROFILE default)

Use it to use the "default" (or your own profile) conan profile rather than inferring settings from CMake. When it is defined, the CMake automatically detected settings are not used at all, and are overridden by the values from the profile.

PROFILE_AUTO

include(conan.cmake)
conan_cmake_run(PROFILE default
                PROFILE_AUTO build_type)

Use the CMake automatically detected value, instead of the profile one. The above means use the profile named "default", but override its content with the build_type automatically detected by CMake.

The precedence for settings definition is:

CMake detected < PROFILE < PROFILE_AUTO < Explicit ``conan_cmake_run()`` args

The ALL value is used to use all detected settings from CMake, instead of the ones defined in the profile:

include(conan.cmake)
conan_cmake_run(PROFILE default
                PROFILE_AUTO ALL)

This is still useful, as the profile can have many other things defined (options, build_requires, etc).

CMAKE_BUILD_TYPE

To use the cmake_multi generator you just need to make sure CMAKE_BUILD_TYPE is empty and use a CMake generator that supports multi-configuration.

If the BUILD_TYPE is explictly passed to conan_cmake_run(), then single configuration cmake generator will be used.

SETTINGS

include(conan.cmake)
conan_cmake_run(...
                SETTINGS arch=armv6
                SETTINGS compiler.cppstd=14)

ENV

include(conan.cmake)
conan_cmake_run(...
                ENV env_var=value
                ENV Pkg:env_var2=value2)

Define command line environment variables. Even if with CMake it is also possible to directly define environment variables, with this syntax you can define environment variables per-package, as the above is equivalent to:

$ conan install .... -e env_var=value -e Pkg:env_var2=value

If environment variables were defined in a given profile, command line arguments have higher precedence, so these values would be used instead of the profiles ones.

INSTALL_FOLDER

Provide the conan install --install-folder=[folder] argument:

include(conan.cmake)
conan_cmake_run(...
                INSTALL_FOLDER myfolder
                )

GENERATORS

Add additional generators. It may useful to add the virtualrunenv-generator:

include(conan.cmake)
conan_cmake_run(...
                GENERATORS virtualrunenv)

CONAN_COMMAND

Use CONAN_COMMAND argument to specify the conan path, e.g. in case of running from source cmake does not identify conan as command, even if it is +x and it is in the path.

include(conan.cmake)
conan_cmake_run(...
                CONAN_COMMAND "path_to_conan")

Other macros and functions

conan_check()

Checks conan availability in PATH. Arguments REQUIRED and VERSION are optional.

Example usage:

conan_check(VERSION 1.0.0 REQUIRED)

conan_add_remote()

Adds a remote. Arguments URL and NAME are required, INDEX and VERIFY_SSL are optional.

Example usage:

conan_add_remote(NAME bincrafters 
                 INDEX 1
                 URL https://api.bintray.com/conan/bincrafters/public-conan
                 VERIFY_SSL True)            

conan_config_install()

Installs a full configuration from a local or remote zip file. Argument ITEM is required, arguments TYPE, SOURCE, TARGET and VERIFY_SSL are optional.

Example usage:

conan_config_install(ITEM ./config.git TYPE git SOURCE src TARGET dst VERIFY_SSL False)

Creating packages

This cmake wrapper launches conan, installing dependencies, and injecting a conan_basic_setup() call. So it is for end-users only, but not necessary at all for creating packages, because conan already downloaded and installed dependencies the moment that a package needs to be built. If you are using the same CMakeLists.txt for both consuming and creating packages, consider doing something like:

if(CONAN_EXPORTED) # in conan local cache
    # standard conan installation, deps will be defined in conanfile.py
    # and not necessary to call conan again, conan is already running
    include(${CMAKE_BINARY_DIR}/conanbuildinfo.cmake)
    conan_basic_setup()
else() # in user space
    include(conan.cmake)
    # Make sure to use conanfile.py to define dependencies, to stay consistent
    conan_cmake_run(CONANFILE conanfile.py
                    BASIC_SETUP)
endif()

Please check the source code for other options and arguments.

Development, contributors

There are some tests, you can run in python, with nosetests, for example:

$ nosetests . --nocapture