New CommonPackageConfig.cmake replaces PackageConfig.cmake

- targets are properly exported with CMake's export(EXPORT) feature - CommonLibrary.cmake adds targets to export set - generated ${PROJECT_NAME}Config.cmake handles build- and install-tree inclusion properly; only find dependencies if the targets are not present, which improves CMake run performance
Eyescale · Aug 17, 2015 · 00d7d4a · 00d7d4a
1 parent d14246f
commit 00d7d4a
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Showing 8 changed files with 249 additions and 558 deletions.
diff --git a/CHANGES.md b/CHANGES.md
@@ -7,7 +7,15 @@
     * Added SHALLOW and VERBOSE options
     * new targets *DIR-rebase* and *rebase* to update git externals and sub
       projects
-* Exported targets provided by PackageConfig.cmake are now generated by
+* CommonPackageConfig.cmake replaces PackageConfig.cmake. It uses the
+  export(EXPORT) feature from CMake 3 to generate ${PROJECT_NAME}Targets.cmake
+  file which provides IMPORTED targets. Client projects should use those targets
+  in target_link_libraries() (or NAME_LINK_LIBRARIES if common_library) rather
+  than ${PROJECT_NAME}_LIBRARIES.
+* New variable NAME_OMIT_EXPORT for common_library() excludes a target from the
+  list of exported targets. This replaces the project-wide
+  ${PROJECT_NAME}_EXCLUDE_LIBRARIES variable.
+* Exported targets provided by CommonPackageConfig.cmake are now generated by
   common_application() and common_library(); generic target hook for
   add_executable() and add_library() does not exist anymore.
 * common_check_targets() now adds cppcheck, cpplint and clangcheck targets

diff --git a/CommonCPack.cmake b/CommonCPack.cmake
@@ -4,7 +4,7 @@
 
 # No support for subproject packaging
 if(NOT PROJECT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)
-  include(PackageConfig)
+  include(CommonPackageConfig)
   return()
 endif()
 
@@ -54,10 +54,6 @@ set(CPACK_PACKAGE_VERSION_MINOR ${VERSION_MINOR})
 set(CPACK_PACKAGE_VERSION_PATCH ${VERSION_PATCH})
 set(CPACK_PACKAGE_VERSION ${VERSION})
 set(CPACK_RESOURCE_FILE_LICENSE ${PROJECT_SOURCE_DIR}/LICENSE.txt)
-if(NOT CPACK_PACKAGE_CONFIG_REQUIRES)
-  string(REPLACE ";" " " CPACK_PACKAGE_CONFIG_REQUIRES
-    "${${UPPER_PROJECT_NAME}_DEPENDENT_LIBRARIES}")
-endif()
 if(NOT CPACK_DEBIAN_BUILD_DEPENDS)
   # setup'd by Buildyard config, same as for travis CI
   set(CPACK_DEBIAN_BUILD_DEPENDS ${${UPPER_PROJECT_NAME}_BUILD_DEBS})
@@ -193,4 +189,4 @@ set(CPACK_PACKAGE_FILE_NAME_BACKUP "${CPACK_PACKAGE_FILE_NAME}")
 include(CPack)
 set(CPACK_PACKAGE_FILE_NAME "${CPACK_PACKAGE_FILE_NAME_BACKUP}")
 
-include(PackageConfig)
+include(CommonPackageConfig)
diff --git a/CommonConfig.cmake.in b/CommonConfig.cmake.in
@@ -0,0 +1,17 @@
+# Generated by CommonPackageConfig.cmake
+
+# if target already exists (subproject build), no need to find any dependencies
+if(TARGET @PROJECT_NAME@_ALIAS)
+  list(APPEND CMAKE_MODULE_PATH "@CMAKE_CURRENT_BINARY_DIR@/@CMAKE_MODULE_INSTALL_PATH@")
+else()
+  list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}")
+
+@DEPENDENT_LIBRARIES@
+  if(EXISTS "${CMAKE_CURRENT_LIST_DIR}/@PROJECT_NAME@Targets.cmake")
+    include("${CMAKE_CURRENT_LIST_DIR}/@PROJECT_NAME@Targets.cmake")
+  endif()
+endif()
+
+if(EXISTS "${CMAKE_CURRENT_LIST_DIR}/options.cmake")
+  include("${CMAKE_CURRENT_LIST_DIR}/options.cmake")
+endif()
diff --git a/CommonLibrary.cmake b/CommonLibrary.cmake
@@ -8,13 +8,16 @@
 # * NAME_SOURCES for all compilation units
 # * NAME_HEADERS for all internal header files
 # * NAME_PUBLIC_HEADERS for public, installed header files
-# * NAME_LINK_LIBRARIES for dependencies of name
+# * NAME_LINK_LIBRARIES for dependencies of name. Use targets rather than
+#   NAME_LIBRARIES variable. Also use PUBLIC and PRIVATE for declaring transient
+#   dependencies for export target generation.
 # * NAME_LIBRARY_TYPE or COMMON_LIBRARY_TYPE for SHARED or STATIC library, with
 #   COMMON_LIBRARY_TYPE being an option stored in the CMakeCache.
 # * NAME_OMIT_LIBRARY_HEADER when set, no library header (name.h) is generated.
 # * NAME_INCLUDE_NAME for the include directory and library header
 # * NAME_NAMESPACE for api.h and version.h
 # * NAME_OMIT_CHECK_TARGETS do not create cppcheck targets
+# * NAME_OMIT_EXPORT do not export target in CommonPackageConfig.cmake
 # * VERSION for the API version
 # * VERSION_ABI for the ABI version
 # * Optional Qt support:
@@ -44,53 +47,18 @@ set(COMMON_LIBRARY_TYPE SHARED CACHE STRING
   "Library type {any combination of SHARED, STATIC}")
 set_property(CACHE COMMON_LIBRARY_TYPE PROPERTY STRINGS SHARED STATIC)
 
-macro(generate_library_header NAME)
-  get_filename_component(__base_name ${INCLUDE_NAME} NAME)
-
-  set(__generated_header ${OUTPUT_INCLUDE_DIR}/${INCLUDE_NAME}/${__base_name}.h)
-  set(__generated_header_in ${__generated_header}.in)
-
-  file(WRITE ${__generated_header_in}
-    "// generated by CommonLibrary.cmake, do not edit\n"
-    "#ifndef ${NAME}_H\n"
-    "#define ${NAME}_H\n")
-    foreach(PUBLIC_HEADER ${PUBLIC_HEADERS})
-      if(IS_ABSOLUTE ${PUBLIC_HEADER})
-        get_filename_component(PUBLIC_HEADER ${PUBLIC_HEADER} NAME)
-      endif()
-      if(NOT PUBLIC_HEADER MATCHES "defines.+\\.h" AND
-        (PUBLIC_HEADER MATCHES ".*\\.h$" OR PUBLIC_HEADER MATCHES ".*\\.hpp$"))
-        file(APPEND ${__generated_header_in}
-          "#include <${INCLUDE_NAME}/${PUBLIC_HEADER}>\n")
-      endif()
-    endforeach()
-  file(APPEND ${__generated_header_in} "#endif\n")
-
-  # configure only touches file if changed, saves compilation after reconfigure
-  configure_file( ${__generated_header_in} ${__generated_header} COPYONLY)
-  list(APPEND PUBLIC_HEADERS ${__generated_header})
-endmacro()
-
-#-------------------------------------------------------------------------------
-# set debug postfix
-#-------------------------------------------------------------------------------
-macro(COMMON_SET_LIB_NAME_POSTFIX)
-  if (WIN32)
-    set(CMAKE_DEBUG_POSTFIX "_D")
-  elseif(COMMON_LIBRARY_DEBUG_POSTFIX)
-    set(CMAKE_DEBUG_POSTFIX "_debug")
-  else()
-    set(CMAKE_DEBUG_POSTFIX "")
-  endif()
-endmacro()
 
 # applying CMAKE_C(XX)_FLAGS to add_library only works from parent scope, hence
 # the macro calling the function _common_library
-macro(COMMON_LIBRARY Name)
+macro(common_library Name)
   common_compiler_flags()
   _common_library(${Name} ${ARGN})
 endmacro()
 
+#-------------------------------------------------------------------------------
+# Implementation
+#-------------------------------------------------------------------------------
+
 function(_common_library Name)
   string(TOUPPER ${Name} NAME)
 
@@ -110,21 +78,24 @@ function(_common_library Name)
   set(PUBLIC_HEADERS ${${NAME}_PUBLIC_HEADERS} ${${NAME}_MOC_PUBLIC_HEADERS})
   set(LINK_LIBRARIES ${${NAME}_LINK_LIBRARIES})
 
-  configure_file(${CMAKE_SOURCE_DIR}/CMake/common/cpp/api.h
-    ${OUTPUT_INCLUDE_DIR}/${INCLUDE_NAME}/api.h @ONLY)
-  configure_file(${CMAKE_SOURCE_DIR}/CMake/common/cpp/version.h
-    ${OUTPUT_INCLUDE_DIR}/${INCLUDE_NAME}/version.h @ONLY)
-  configure_file(${CMAKE_SOURCE_DIR}/CMake/common/cpp/version.cpp
-    ${CMAKE_CURRENT_BINARY_DIR}/version.cpp @ONLY)
-
-  # ${NAMESPACE}_API= -> Fix cppcheck error about not including version.h
-  list(APPEND CPPCHECK_EXTRA_ARGS
-    -D${NAME}_STATIC= -D${NAMESPACE}_API=)
-
-  list(APPEND PUBLIC_HEADERS
-    ${OUTPUT_INCLUDE_DIR}/${INCLUDE_NAME}/api.h
-    ${OUTPUT_INCLUDE_DIR}/${INCLUDE_NAME}/version.h)
-  list(APPEND SOURCES ${CMAKE_CURRENT_BINARY_DIR}/version.cpp)
+  # Generate api.h and version.h/cpp for non-interface libraries
+  if(${NAME}_SOURCES)
+    configure_file(${CMAKE_SOURCE_DIR}/CMake/common/cpp/api.h
+      ${OUTPUT_INCLUDE_DIR}/${INCLUDE_NAME}/api.h @ONLY)
+    configure_file(${CMAKE_SOURCE_DIR}/CMake/common/cpp/version.h
+      ${OUTPUT_INCLUDE_DIR}/${INCLUDE_NAME}/version.h @ONLY)
+    configure_file(${CMAKE_SOURCE_DIR}/CMake/common/cpp/version.cpp
+      ${CMAKE_CURRENT_BINARY_DIR}/version.cpp @ONLY)
+
+    # ${NAMESPACE}_API= -> Fix cppcheck error about not including version.h
+    list(APPEND CPPCHECK_EXTRA_ARGS
+      -D${NAME}_STATIC= -D${NAMESPACE}_API=)
+
+    list(APPEND PUBLIC_HEADERS
+      ${OUTPUT_INCLUDE_DIR}/${INCLUDE_NAME}/api.h
+      ${OUTPUT_INCLUDE_DIR}/${INCLUDE_NAME}/version.h)
+    list(APPEND SOURCES ${CMAKE_CURRENT_BINARY_DIR}/version.cpp)
+  endif()
 
   if(NOT ${NAME}_OMIT_LIBRARY_HEADER)
     generate_library_header(${NAME})
@@ -159,56 +130,71 @@ function(_common_library Name)
     if(TARGET ${Name})
       set(LibName "${Name}_${LIBRARY_TYPE}")
     endif()
-    add_library(${LibName} ${LIBRARY_TYPE} ${SOURCES} ${HEADERS} ${PUBLIC_HEADERS})
-    set_target_properties(${LibName} PROPERTIES
-      VERSION ${VERSION} SOVERSION ${VERSION_ABI}
-      OUTPUT_NAME ${Name} FOLDER ${PROJECT_NAME})
-    # append a debug suffix to library name on windows or if user requests it
-    common_set_lib_name_postfix()
-    target_link_libraries(${LibName} ${LINK_LIBRARIES})
-    install(TARGETS ${LibName}
-      ARCHIVE DESTINATION ${LIBRARY_DIR} COMPONENT dev
-      RUNTIME DESTINATION bin COMPONENT lib
-      LIBRARY DESTINATION ${LIBRARY_DIR} COMPONENT lib)
-
-    if(NOT ${NAME}_OMIT_CHECK_TARGETS)
-      common_check_targets(${LibName})
-    endif()
-
-    # ignore user-specified targets, e.g. language bindings
-    list(FIND IGNORE_LIB_TARGETS ${LibName} _ignore_target)
-
-    if(_ignore_target EQUAL -1)
-      # add defines TARGET_DSO_NAME and TARGET_SHARED for dlopen() usage
-      get_target_property(_compile_definitions ${LibName} COMPILE_DEFINITIONS)
-      if(NOT _compile_definitions)
-        set(_compile_definitions) # clear _compile_definitions-NOTFOUND
-      endif()
 
-      if(MSVC OR XCODE_VERSION)
-        set(_libraryname ${CMAKE_SHARED_LIBRARY_PREFIX}${LibName}${CMAKE_SHARED_LIBRARY_SUFFIX})
-      else()
-        if(APPLE)
-          set(_libraryname ${CMAKE_SHARED_LIBRARY_PREFIX}${LibName}.${VERSION_ABI}${CMAKE_SHARED_LIBRARY_SUFFIX})
-        else()
-          set(_libraryname ${CMAKE_SHARED_LIBRARY_PREFIX}${LibName}${CMAKE_SHARED_LIBRARY_SUFFIX}.${VERSION_ABI})
-        endif()
+    if(NOT ${NAME}_SOURCES)
+      # fake add_library(${LibName} INTERFACE) from CMake 3
+      add_library(${LibName} ${PUBLIC_HEADERS})
+      set_target_properties(${LibName} PROPERTIES
+        LINKER_LANGUAGE CXX FOLDER ${PROJECT_NAME})
+
+      # declare include directories for this target when using it in the build
+      # tree; the install tree include directory is declared via install()
+      target_include_directories(${LibName} INTERFACE
+        "$<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}>"
+        "$<BUILD_INTERFACE:${OUTPUT_INCLUDE_DIR}>"
+        "$<BUILD_INTERFACE:${PROJECT_BINARY_DIR}>"
+      )
+    else()
+      # append a debug suffix to library name on windows or if user requests it
+      common_set_lib_name_postfix()
+
+      add_library(${LibName} ${LIBRARY_TYPE} ${SOURCES} ${HEADERS} ${PUBLIC_HEADERS})
+      set_target_properties(${LibName} PROPERTIES
+        VERSION ${VERSION} SOVERSION ${VERSION_ABI}
+        OUTPUT_NAME ${Name} FOLDER ${PROJECT_NAME})
+      target_link_libraries(${LibName} ${LINK_LIBRARIES})
+
+      # declare include directories for this target when using it in the build
+      # tree; the install tree include directory is declared via install()
+      target_include_directories(
+          ${LibName} PUBLIC
+          "$<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}>"
+          "$<BUILD_INTERFACE:${OUTPUT_INCLUDE_DIR}>"
+          "$<BUILD_INTERFACE:${PROJECT_BINARY_DIR}>"
+      )
+
+      if(NOT ${NAME}_OMIT_CHECK_TARGETS)
+        common_check_targets(${LibName})
       endif()
 
-      string(TOUPPER ${LibName} LIBNAME)
-      list(APPEND _compile_definitions
-        ${LIBNAME}_SHARED ${LIBNAME}_DSO_NAME=\"${_libraryname}\")
-
-      set_target_properties(${LibName} PROPERTIES
-        COMPILE_DEFINITIONS "${_compile_definitions}")
+      common_enable_dlopen_usage(${LibName})
 
       # for DoxygenRule.cmake and SubProject.cmake
       set_property(GLOBAL APPEND PROPERTY ${PROJECT_NAME}_ALL_DEP_TARGETS
         ${LibName})
+    endif()
 
-      # for PackageConfig.cmake
-      set_property(GLOBAL APPEND PROPERTY ${PROJECT_NAME}_ALL_LIB_TARGETS
-        ${LibName})
+    # add an alias with PROJECT_NAME to the target to ease detection of
+    # subproject inclusion in CommonConfig.cmake
+    if(NOT TARGET ${PROJECT_NAME}_ALIAS)
+      add_library(${PROJECT_NAME}_ALIAS ALIAS ${LibName})
+    endif()
+
+    # add target to export set if not excluded, written by
+    # CommonPackageConfig.cmake
+    if(${NAME}_OMIT_EXPORT)
+      install(TARGETS ${LibName}
+        ARCHIVE DESTINATION ${LIBRARY_DIR} COMPONENT dev
+        RUNTIME DESTINATION bin COMPONENT lib
+        LIBRARY DESTINATION ${LIBRARY_DIR} COMPONENT lib
+        INCLUDES DESTINATION include)
+    else()
+      install(TARGETS ${LibName}
+        EXPORT ${PROJECT_NAME}Targets
+        ARCHIVE DESTINATION ${LIBRARY_DIR} COMPONENT dev
+        RUNTIME DESTINATION bin COMPONENT lib
+        LIBRARY DESTINATION ${LIBRARY_DIR} COMPONENT lib
+        INCLUDES DESTINATION include)
     endif()
   endforeach()
 
@@ -223,3 +209,62 @@ function(_common_library Name)
   install_files(include/${INCLUDE_NAME}
     FILES ${PUBLIC_HEADERS} COMPONENT dev)
 endfunction()
+
+macro(generate_library_header NAME)
+  get_filename_component(__base_name ${INCLUDE_NAME} NAME)
+
+  set(__generated_header ${OUTPUT_INCLUDE_DIR}/${INCLUDE_NAME}/${__base_name}.h)
+  set(__generated_header_in ${__generated_header}.in)
+
+  file(WRITE ${__generated_header_in}
+    "// generated by CommonLibrary.cmake, do not edit\n"
+    "#ifndef ${NAME}_H\n"
+    "#define ${NAME}_H\n")
+    foreach(PUBLIC_HEADER ${PUBLIC_HEADERS})
+      if(IS_ABSOLUTE ${PUBLIC_HEADER})
+        get_filename_component(PUBLIC_HEADER ${PUBLIC_HEADER} NAME)
+      endif()
+      if(NOT PUBLIC_HEADER MATCHES "defines.+\\.h" AND
+        (PUBLIC_HEADER MATCHES ".*\\.h$" OR PUBLIC_HEADER MATCHES ".*\\.hpp$"))
+        file(APPEND ${__generated_header_in}
+          "#include <${INCLUDE_NAME}/${PUBLIC_HEADER}>\n")
+      endif()
+    endforeach()
+  file(APPEND ${__generated_header_in} "#endif\n")
+
+  # configure only touches file if changed, saves compilation after reconfigure
+  configure_file( ${__generated_header_in} ${__generated_header} COPYONLY)
+  list(APPEND PUBLIC_HEADERS ${__generated_header})
+endmacro()
+
+macro(common_set_lib_name_postfix)
+  if(WIN32)
+    set(CMAKE_DEBUG_POSTFIX "_D")
+  elseif(COMMON_LIBRARY_DEBUG_POSTFIX)
+    set(CMAKE_DEBUG_POSTFIX "_debug")
+  else()
+    set(CMAKE_DEBUG_POSTFIX "")
+  endif()
+endmacro()
+
+# add defines TARGET_DSO_NAME and TARGET_SHARED for dlopen() usage
+function(common_enable_dlopen_usage Target)
+  get_target_property(_compile_definitions ${Target} COMPILE_DEFINITIONS)
+  if(NOT _compile_definitions)
+    set(_compile_definitions) # clear _compile_definitions-NOTFOUND
+  endif()
+  if(MSVC OR XCODE_VERSION)
+    set(_DSOName ${CMAKE_SHARED_LIBRARY_PREFIX}${Target}${CMAKE_SHARED_LIBRARY_SUFFIX})
+  else()
+    if(APPLE)
+      set(_DSOName ${CMAKE_SHARED_LIBRARY_PREFIX}${Target}.${VERSION_ABI}${CMAKE_SHARED_LIBRARY_SUFFIX})
+    else()
+      set(_DSOName ${CMAKE_SHARED_LIBRARY_PREFIX}${Target}${CMAKE_SHARED_LIBRARY_SUFFIX}.${VERSION_ABI})
+    endif()
+  endif()
+  string(TOUPPER ${Target} TARGET)
+  list(APPEND _compile_definitions
+    ${TARGET}_SHARED ${TARGET}_DSO_NAME=\"${_DSOName}\")
+  set_target_properties(${Target} PROPERTIES
+    COMPILE_DEFINITIONS "${_compile_definitions}")
+endfunction()
diff --git a/CommonPackage.cmake b/CommonPackage.cmake
@@ -122,7 +122,7 @@ macro(common_package Package_Name)
     string(REGEX REPLACE "-" "_" __use_package_define ${__use_package_define})
     list(APPEND COMMON_PACKAGE_DEFINES ${__use_package_define})
 
-    # for PackageConfig.cmake
+    # for CommonPackageConfig.cmake
     if(NOT COMMON_LIBRARY_TYPE MATCHES "SHARED")
       list(APPEND ${UPPER_PROJECT_NAME}_DEPENDENT_LIBRARIES ${Package_Name})
     endif()