libevent/cmake/LibeventConfig.cmake.in

# - Config file for the Libevent package
# It defines the following variables
#  LIBEVENT_FOUND            - true if libevent and all required components found on the system
#  LIBEVENT_xxx_FOUND        - true if component xxx(see available components) found on the system
#  LIBEVENT_VERSION          - libevent version in format Major.Minor.Patch
#  LIBEVENT_INCLUDE_DIRS     - directories where libevent header is located.
#  LIBEVENT_INCLUDE_DIR      - same as DIRS
#  LIBEVENT_LIBRARIES        - libevent library to link against.
#  LIBEVENT_LIBRARY          - same as LIBRARIES
#
# These variables are deprecated, don't use them.
#  LIBEVENT_STATIC_LIBRARIES - libraries to link against (archive/static)
#  LIBEVENT_SHARED_LIBRARIES - libraries to link against (shared)
#
# When you try to locate the libevent libraries, you should specify which components you want to use.
# The following table lists all available components. If none is given, all imported targets will used.
#  core        - the core functons of libevent
#  extra       - extra functions, contains http, dns and rpc
#  pthreads    - multiple threads for libevent, does not exist on Windows
#  openssl     - OpenSSL support for libevent
#  mbedtls     - MbedTLS support for libevent
#
# By default, the shared libraries of libevent will be found. To find the static ones instead,
# you must set the LIBEVENT_STATIC_LINK variable to TRUE before calling find_package(Libevent ...).
# If no component provided, all components will be used.
# example:
#  set(LIBEVENT_STATIC_LINK TRUE)
#  find_package(Libevent 2.2 REQUIRED COMPONENTS core)
#  include_directories(${LIBEVENT_INCLUDE_DIRS})  # Can be omitted
#  target_link_libraries(myapp ${LIBEVENT_LIBRARIES})
#    or target_link_libraries(myapp libevent::core)
#
# find_package() can handle dependencies automatically. For example, given the 'openssl' component,
# all dependencies (libevent_core, libssl, libcrypto and openssl include directories) will be found.

set(LIBEVENT_VERSION @EVENT_PACKAGE_VERSION@)

# Load the dependencies of all components. As find_dependency propagates the original
# find_package attributes (i.e. required or not), there's no need to repeat this or filter
# by component.
include(CMakeFindDependencyMacro)
find_dependency(Threads)
find_dependency(MbedTLS)
find_dependency(OpenSSL)

# IMPORTED targets from LibeventTargets.cmake
set(LIBEVENT_STATIC_LIBRARIES "@LIBEVENT_STATIC_LIBRARIES@")
set(LIBEVENT_SHARED_LIBRARIES "@LIBEVENT_SHARED_LIBRARIES@")

# Default to the same type as libevent was built:
if(NOT DEFINED LIBEVENT_STATIC_LINK)
    set(LIBEVENT_STATIC_LINK NOT @EVENT_LIBRARY_SHARED@)
endif()

if(${LIBEVENT_STATIC_LINK})
    set(_LIB_TYPE static)
    set(_AVAILABLE_LIBS "${LIBEVENT_STATIC_LIBRARIES}")

    # CMake before 3.15 doesn't link OpenSSL to pthread/dl, do it ourselves instead
    if (${CMAKE_VERSION} VERSION_LESS "3.15.0" AND ${LIBEVENT_STATIC_LINK} AND ${OPENSSL_FOUND} AND ${Threads_FOUND})
        set_property(TARGET OpenSSL::Crypto APPEND PROPERTY INTERFACE_LINK_LIBRARIES Threads::Threads)
        set_property(TARGET OpenSSL::Crypto APPEND PROPERTY INTERFACE_LINK_LIBRARIES ${CMAKE_DL_LIBS})
    endif ()
else()
    set(_LIB_TYPE shared)
    set(_AVAILABLE_LIBS "${LIBEVENT_SHARED_LIBRARIES}")
endif()

macro(message_if_needed _flag _msg)
    if (NOT ${CMAKE_FIND_PACKAGE_NAME}_FIND_QUIETLY)
        message(${_flag} "${_msg}")
    endif()
endmacro()

macro(no_component_msg _comp)
    if(${CMAKE_FIND_PACKAGE_NAME}_FIND_REQUIRED_${_comp})
        set(pthreadlib)
        if(NOT WIN32)
            set(pthreadlib ", pthreads")
        endif()
        message(FATAL_ERROR "Your libevent library does not contain a ${_comp} component!\n"
                "The valid components are core, extra${pthreadlib}, openssl and mbedtls.")
    else()
        message_if_needed(WARNING "Your libevent library does not contain a ${_comp} component!")
    endif()
endmacro()

set(_EVENT_COMPONENTS)
if(${CMAKE_FIND_PACKAGE_NAME}_FIND_COMPONENTS)
    list(REMOVE_DUPLICATES ${CMAKE_FIND_PACKAGE_NAME}_FIND_COMPONENTS)
    foreach(_comp ${${CMAKE_FIND_PACKAGE_NAME}_FIND_COMPONENTS})
        list(FIND _AVAILABLE_LIBS ${_comp} _INDEX)
        if(_INDEX GREATER -1)
            list(APPEND _EVENT_COMPONENTS ${_comp})
        else()
            no_component_msg(${_comp})
        endif()
    endforeach()
else()
    set(_EVENT_COMPONENTS ${_AVAILABLE_LIBS})
endif()

set(_POSSIBLE_PKG_NAMES)
list(APPEND _POSSIBLE_PKG_NAMES ${CMAKE_FIND_PACKAGE_NAME} LIBEVENT Libevent libevent)
list(REMOVE_DUPLICATES _POSSIBLE_PKG_NAMES)

macro(set_case_insensitive_found _comp)
    foreach(name ${_POSSIBLE_PKG_NAMES})
        if("${_comp}" STREQUAL "")
            set(${name}_FOUND TRUE)
            set(${name}_NOTFOUND FALSE)
        else()
            set(${name}_${_comp}_FOUND TRUE)
            set(${name}_${_comp}_NOTFOUND FALSE)
        endif()
    endforeach()
endmacro()

foreach(_comp ${_EVENT_COMPONENTS})
    list(APPEND LIBEVENT_LIBRARIES "libevent::${_comp}")
    set_case_insensitive_found(${_comp})
endforeach()

if(LIBEVENT_LIBRARIES)
    set(LIBEVENT_LIBRARY ${LIBEVENT_LIBRARIES})

    # Avoid including targets more than once.
    if(NOT TARGET libevent::core)
        # Include the project Targets file, this contains definitions for IMPORTED targets.
        include(${CMAKE_CURRENT_LIST_DIR}/LibeventTargets-${_LIB_TYPE}.cmake)
    endif()
    get_target_property(LIBEVENT_INCLUDE_DIRS libevent::core INTERFACE_INCLUDE_DIRECTORIES)
    get_filename_component(LIBEVENT_INSTALL_PREFIX "${LIBEVENT_INCLUDE_DIRS}" PATH)
    message_if_needed(STATUS "Found libevent ${LIBEVENT_VERSION} in ${LIBEVENT_INSTALL_PREFIX}")
else()
    if(${CMAKE_FIND_PACKAGE_NAME}_FIND_REQUIRED)
        message(FATAL_ERROR "Can not find any libraries for libevent.")
    else()
        message_if_needed(WARNING "Can not find any libraries for libevent.")
    endif()
endif()
set(LIBEVENT_INCLUDE_DIR ${LIBEVENT_INCLUDE_DIRS})

unset(_LIB_TYPE)
unset(_AVAILABLE_LIBS)
unset(_EVENT_COMPONENTS)
unset(_POSSIBLE_PKG_NAMES)