vcpkg/scripts/cmake/vcpkg_check_linkage.cmake

## # vcpkg_check_linkage
##
## Asserts the available library and CRT linkage options for the port.
##
## ## Usage
## ```cmake
## vcpkg_check_linkage(
##     [ONLY_STATIC_LIBRARY | ONLY_DYNAMIC_LIBRARY]
##     [ONLY_STATIC_CRT | ONLY_DYNAMIC_CRT]
## )
## ```
##
## ## Parameters
## ### ONLY_STATIC_LIBRARY
## Indicates that this port can only be built with static library linkage.
##
## ### ONLY_DYNAMIC_LIBRARY
## Indicates that this port can only be built with dynamic/shared library linkage.
##
## ### ONLY_STATIC_CRT
## Indicates that this port can only be built with static CRT linkage.
##
## ### ONLY_DYNAMIC_CRT
## Indicates that this port can only be built with dynamic/shared CRT linkage.
##
## ## Notes
## This command will either alter the settings for `VCPKG_LIBRARY_LINKAGE` or fail, depending on what was requested by the user versus what the library supports.
##
## ## Examples
##
## * [libimobiledevice](https://github.com/Microsoft/vcpkg/blob/master/ports/libimobiledevice/portfile.cmake)
function(vcpkg_check_linkage)
    cmake_parse_arguments(_csc "ONLY_STATIC_LIBRARY;ONLY_DYNAMIC_LIBRARY;ONLY_DYNAMIC_CRT;ONLY_STATIC_CRT" "" "" ${ARGN})

    if(_csc_ONLY_STATIC_LIBRARY AND VCPKG_LIBRARY_LINKAGE STREQUAL "dynamic")
        message(STATUS "Note: ${PORT} only supports static library linkage. Building static library.")
        set(VCPKG_LIBRARY_LINKAGE static PARENT_SCOPE)
    endif()
    if(_csc_ONLY_DYNAMIC_LIBRARY AND VCPKG_LIBRARY_LINKAGE STREQUAL "static")
        message(STATUS "Note: ${PORT} only supports dynamic library linkage. Building dynamic library.")
        if(VCPKG_CRT_LINKAGE STREQUAL "static")
            message(FATAL_ERROR "Refusing to build unexpected dynamic library against the static CRT. If this is desired, please configure your triplet to directly request this configuration.")
        endif()
        set(VCPKG_LIBRARY_LINKAGE dynamic PARENT_SCOPE)
    endif()

    if(_csc_ONLY_DYNAMIC_CRT AND VCPKG_CRT_LINKAGE STREQUAL "static")
        message(FATAL_ERROR "${PORT} only supports dynamic crt linkage")
    endif()
    if(_csc_ONLY_STATIC_CRT AND VCPKG_CRT_LINKAGE STREQUAL "dynamic")
        message(FATAL_ERROR "${PORT} only supports static crt linkage")
    endif()
endfunction()