cmake: Rename targets to gflags[_nothreads]_(static|shared), support

find_package COMPONENTS

CMakeLists.txt

@@ -15,7 +15,7 @@
 ## When this project is a subproject (GFLAGS_IS_SUBPROJECT is TRUE), the default
 ## settings are such that only the static single-threaded library is built without
 ## installation of the gflags files. The "gflags" target is in this case an ALIAS
-## library target for the "gflags_nothreads-static" library target. Targets which
+## library target for the "gflags_nothreads_static" library target. Targets which
 ## depend on the gflags library should link to the "gflags" library target.
 ##
 ## Example CMakeLists.txt of user project which requires separate gflags installation:
@@ -28,6 +28,16 @@
 ##   add_executable(foo src/foo.cc)
 ##   target_link_libraries(foo gflags)
 ##
+## Example CMakeLists.txt of user project which requires separate single-threaded static gflags installation:
+##   cmake_minimum_required(VERSION 2.8.12 FATAL_ERROR)
+##
+##   project(Foo)
+##
+##   find_package(gflags COMPONENTS nothreads_static)
+##
+##   add_executable(foo src/foo.cc)
+##   target_link_libraries(foo gflags)
+##
 ## Example CMakeLists.txt of super-project which contains gflags source tree:
 ##   cmake_minimum_required(VERSION 2.8.12 FATAL_ERROR)
 ##
@@ -411,12 +421,12 @@ foreach (TYPE IN ITEMS STATIC SHARED)
     # multi-threaded vs. single-threaded
     foreach (opts IN ITEMS "" _nothreads)
       if (BUILD_gflags${opts}_LIB)
-        add_library (gflags${opts}-${type} ${TYPE} ${GFLAGS_SRCS} ${PRIVATE_HDRS} ${PUBLIC_HDRS})
+        add_library (gflags${opts}_${type} ${TYPE} ${GFLAGS_SRCS} ${PRIVATE_HDRS} ${PUBLIC_HDRS})
         set (include_dirs "$<BUILD_INTERFACE:${PROJECT_BINARY_DIR}/include>")
         if (INSTALL_HEADERS)
           list (APPEND include_dirs "$<INSTALL_INTERFACE:${INCLUDE_INSTALL_DIR}>")
         endif ()
-        target_include_directories (gflags${opts}-${type}
+        target_include_directories (gflags${opts}_${type}
           PUBLIC  "${include_dirs}"
           PRIVATE "${PROJECT_SOURCE_DIR}/src;${PROJECT_BINARY_DIR}/include/${GFLAGS_INCLUDE_DIR}"
         )
@@ -425,25 +435,25 @@ foreach (TYPE IN ITEMS STATIC SHARED)
         else ()
           set (defines "GFLAGS_IS_A_DLL=${GFLAGS_IS_A_DLL}")
           if (CMAKE_USE_PTHREADS_INIT)
-            target_link_libraries (gflags${opts}-${type} ${CMAKE_THREAD_LIBS_INIT})
+            target_link_libraries (gflags${opts}_${type} ${CMAKE_THREAD_LIBS_INIT})
           endif ()
         endif ()
         set_target_properties (
-          gflags${opts}-${type} PROPERTIES COMPILE_DEFINITIONS "${defines}"
+          gflags${opts}_${type} PROPERTIES COMPILE_DEFINITIONS "${defines}"
                                            OUTPUT_NAME         "gflags${opts}${type_suffix}"
                                            VERSION             "${PACKAGE_VERSION}"
                                            SOVERSION           "${PACKAGE_SOVERSION}"
         )
         if (HAVE_SHLWAPI_H)
-          target_link_libraries (gflags${opts}-${type} shlwapi.lib)
+          target_link_libraries (gflags${opts}_${type} shlwapi.lib)
         endif ()
-        list (APPEND TARGETS gflags${opts}-${type})
+        list (APPEND TARGETS gflags${opts}_${type})
         # add convenience make target for build of both shared and static libraries
         if (NOT GFLAGS_IS_SUBPROJECT)
           if (NOT TARGET gflags${opts})
             add_custom_target (gflags${opts})
           endif ()
-          add_dependencies (gflags${opts} gflags${opts}-${type})
+          add_dependencies (gflags${opts} gflags${opts}_${type})
         endif ()
       endif ()
     endforeach ()
@@ -454,8 +464,8 @@ endforeach ()
 if (GFLAGS_IS_SUBPROJECT)
   foreach (type IN ITEMS static shared)
     foreach (opts IN ITEMS "_nothreads" "")
-      if (TARGET gflags${opts}-${type})
-        add_library (gflags ALIAS gflags${opts}-${type})
+      if (TARGET gflags${opts}_${type})
+        add_library (gflags ALIAS gflags${opts}_${type})
         break ()
       endif ()
     endforeach ()
@@ -474,14 +484,14 @@ configure_file (cmake/version.cmake.in "${PROJECT_BINARY_DIR}/${PACKAGE_NAME}-co
 if (BUILD_SHARED_LIBS AND INSTALL_SHARED_LIBS)
   foreach (opts IN ITEMS "" _nothreads)
     if (BUILD_gflags${opts}_LIB)
-      install (TARGETS gflags${opts}-shared DESTINATION ${LIBRARY_INSTALL_DIR} EXPORT gflags-lib)
+      install (TARGETS gflags${opts}_shared DESTINATION ${LIBRARY_INSTALL_DIR} EXPORT gflags-lib)
     endif ()
   endforeach ()
 endif ()
 if (BUILD_STATIC_LIBS AND INSTALL_STATIC_LIBS)
   foreach (opts IN ITEMS "" _nothreads)
     if (BUILD_gflags${opts}_LIB)
-      install (TARGETS gflags${opts}-static DESTINATION ${LIBRARY_INSTALL_DIR} EXPORT gflags-lib)
+      install (TARGETS gflags${opts}_static DESTINATION ${LIBRARY_INSTALL_DIR} EXPORT gflags-lib)
     endif ()
   endforeach ()
 endif ()
@@ -497,7 +507,7 @@ if (INSTALL_HEADERS)
     FILES "${PROJECT_BINARY_DIR}/${PACKAGE_NAME}-config-version.cmake"
     DESTINATION ${CONFIG_INSTALL_DIR}
   )
-  install (EXPORT gflags-lib DESTINATION ${CONFIG_INSTALL_DIR} FILE ${PACKAGE_NAME}-export.cmake)
+  install (EXPORT gflags-lib DESTINATION ${CONFIG_INSTALL_DIR} FILE ${PACKAGE_NAME}-targets.cmake)
   if (UNIX)
     install (PROGRAMS src/gflags_completions.sh DESTINATION ${RUNTIME_INSTALL_DIR})
   endif ()
@@ -506,7 +516,7 @@ endif ()
 # ----------------------------------------------------------------------------
 # support direct use of build tree
 set (INSTALL_PREFIX_REL2CONFIG_DIR .)
-export (TARGETS ${TARGETS} FILE "${PROJECT_BINARY_DIR}/${PACKAGE_NAME}-export.cmake")
+export (TARGETS ${TARGETS} FILE "${PROJECT_BINARY_DIR}/${PACKAGE_NAME}-targets.cmake")
 export (PACKAGE gflags)
 configure_file (cmake/config.cmake.in "${PROJECT_BINARY_DIR}/${PACKAGE_NAME}-config.cmake" @ONLY)
 

cmake/config.cmake.in

@@ -7,7 +7,7 @@ set (@PACKAGE_PREFIX@_VERSION_MINOR  @PACKAGE_VERSION_MINOR@)
 set (@PACKAGE_PREFIX@_VERSION_PATCH  @PACKAGE_VERSION_PATCH@)
 
 # import targets
-include ("${CMAKE_CURRENT_LIST_DIR}/@PACKAGE_NAME@-export.cmake")
+include ("${CMAKE_CURRENT_LIST_DIR}/@PACKAGE_NAME@-targets.cmake")
 
 # installation prefix
 get_filename_component (CMAKE_CURRENT_LIST_DIR "${CMAKE_CURRENT_LIST_FILE}" PATH)
@@ -20,20 +20,51 @@ get_filename_component (_INSTALL_PREFIX "${CMAKE_CURRENT_LIST_DIR}/@INSTALL_PREF
 # manually to the include search path for targets which link to gflags.
 set (@PACKAGE_PREFIX@_INCLUDE_DIR "${_INSTALL_PREFIX}/@INCLUDE_INSTALL_DIR@")
 
-# default settings
+if (@PACKAGE_NAME@_FIND_COMPONENTS)
+  foreach (@PACKAGE_NAME@_FIND_COMPONENT IN LISTS @PACKAGE_NAME@_FIND_COMPONENTS)
+    if (@PACKAGE_NAME@_FIND_REQUIRED_${@PACKAGE_NAME@_FIND_COMPONENT} AND NOT TARGET @PACKAGE_NAME@_${@PACKAGE_NAME@_FIND_COMPONENT})
+      message (FATAL_ERROR "Package @PACKAGE_NAME@ was installed without required component ${@PACKAGE_NAME@_FIND_COMPONENT}!")
+    endif ()
+  endforeach ()
+  list (GET @PACKAGE_NAME@_FIND_COMPONENTS 0 @PACKAGE_NAME@_FIND_COMPONENT)
+else ()
+  set (@PACKAGE_NAME@_FIND_COMPONENT)
+endif ()
+
+# default settings of @PACKAGE_PREFIX@_SHARED and @PACKAGE_PREFIX@_NOTHREADS
+#
+# It is recommended to use either one of the following find_package commands
+# instead of setting the @PACKAGE_PREFIX@_(SHARED|NOTHREADS) variables:
+# - find_package(@PACKAGE_NAME@ REQUIRED)
+# - find_package(@PACKAGE_NAME@ COMPONENTS nothreads_static)
+# - find_package(@PACKAGE_NAME@ COMPONENTS nothreads_shared)
+# - find_package(@PACKAGE_NAME@ COMPONENTS static)
+# - find_package(@PACKAGE_NAME@ COMPONENTS shared)
 if (NOT DEFINED @PACKAGE_PREFIX@_SHARED)
   if (DEFINED @PACKAGE_NAME@_SHARED)
     set (@PACKAGE_PREFIX@_SHARED ${@PACKAGE_NAME@_SHARED})
-  elseif (TARGET @PACKAGE_NAME@-static OR TARGET @PACKAGE_NAME@_nothreads-static)
-    set (@PACKAGE_PREFIX@_SHARED FALSE)
+  elseif (@PACKAGE_NAME@_FIND_COMPONENT)
+    if (@PACKAGE_NAME@_FIND_COMPONENT MATCHES "shared")
+      set (@PACKAGE_PREFIX@_SHARED TRUE)
     else ()
+      set (@PACKAGE_PREFIX@_SHARED FALSE)
+    endif ()
+  elseif (TARGET @PACKAGE_NAME@_shared OR TARGET @PACKAGE_NAME@_nothreads_shared)
     set (@PACKAGE_PREFIX@_SHARED TRUE)
+  else ()
+    set (@PACKAGE_PREFIX@_SHARED FALSE)
   endif ()
 endif ()
 if (NOT DEFINED @PACKAGE_PREFIX@_NOTHREADS)
   if (DEFINED @PACKAGE_NAME@_NOTHREADS)
     set (@PACKAGE_PREFIX@_NOTHREADS ${@PACKAGE_NAME@_NOTHREADS})
-  elseif (TARGET @PACKAGE_NAME@-static OR TARGET @PACKAGE_NAME@-shared)
+  elseif (@PACKAGE_NAME@_FIND_COMPONENT)
+    if (@PACKAGE_NAME@_FIND_COMPONENT MATCHES "nothreads")
+      set (@PACKAGE_PREFIX@_NOTHREADS TRUE)
+    else ()
+      set (@PACKAGE_PREFIX@_NOTHREADS FALSE)
+    endif ()
+  elseif (TARGET @PACKAGE_NAME@_static OR TARGET @PACKAGE_NAME@_shared)
     set (@PACKAGE_PREFIX@_NOTHREADS FALSE)
   else ()
     set (@PACKAGE_PREFIX@_NOTHREADS TRUE)
@@ -46,15 +77,15 @@ if (NOT @PACKAGE_PREFIX@_TARGET)
     set (@PACKAGE_PREFIX@_TARGET ${@PACKAGE_NAME@_TARGET})
   elseif (@PACKAGE_PREFIX@_SHARED)
     if (@PACKAGE_PREFIX@_NOTHREADS)
-      set (@PACKAGE_PREFIX@_TARGET @PACKAGE_NAME@_nothreads-shared)
+      set (@PACKAGE_PREFIX@_TARGET @PACKAGE_NAME@_nothreads_shared)
     else ()
-      set (@PACKAGE_PREFIX@_TARGET @PACKAGE_NAME@-shared)
+      set (@PACKAGE_PREFIX@_TARGET @PACKAGE_NAME@_shared)
     endif ()
   else ()
     if (@PACKAGE_PREFIX@_NOTHREADS)
-      set (@PACKAGE_PREFIX@_TARGET @PACKAGE_NAME@_nothreads-static)
+      set (@PACKAGE_PREFIX@_TARGET @PACKAGE_NAME@_nothreads_static)
     else ()
-      set (@PACKAGE_PREFIX@_TARGET @PACKAGE_NAME@-static)
+      set (@PACKAGE_PREFIX@_TARGET @PACKAGE_NAME@_static)
     endif ()
   endif ()
 endif ()
@@ -133,4 +164,5 @@ if (NOT "^@PACKAGE_NAME@$" STREQUAL "^@PACKAGE_PREFIX@$")
 endif ()
 
 # unset private variables
+unset (@PACKAGE_NAME@_FIND_COMPONENT)
 unset (_INSTALL_PREFIX)

test/CMakeLists.txt

@@ -22,9 +22,9 @@ else ()
   set (type static)
 endif ()
 if (BUILD_gflags_LIB)
-  link_libraries (gflags-${type})
+  link_libraries (gflags_${type})
 else ()
-  link_libraries (gflags_nothreads-${type})
+  link_libraries (gflags_nothreads_${type})
 endif ()
 
 # ----------------------------------------------------------------------------