Use standard CMake constructs to export the library's targets. (#260)

* Use standard CMake constructs to export the library's targets. * Fix typo. * Document that PCRE2_USE_STATIC_LIBS is not required if only one edition of the library has been built. * Replace some missed stuff from previous review. * Don't explicitly set `PCRE2_FOUND` to true. * Avoid defining the target aliases if they are already defined. * Set `PCRE2_LIBRARIES` and `PCRE2_***_LIBRARY` for compatibility. * Change `PCRE2_USE_STATIC_LIBS` to prohibit loading the shared library if set.
PCRE2Project · Aug 15, 2023 · def175f · def175f
1 parent 6bc8ccf
commit def175f
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Showing 3 changed files with 77 additions and 127 deletions.
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -101,6 +101,7 @@
 # 2021-08-28 PH added test for realpath()
 # 2022-12-10 PH added support for pcre2posix_test
 # 2023-01-15 Carlo added C99 as the minimum required
+# 2023-06-03 Theodore used standard CMake constructs to export the library's targets.
 # 2023-08-06 PH added support for setting variable length lookbehind maximum
 
 # Increased minimum to 3.3 to support visibility.
@@ -142,6 +143,7 @@ INCLUDE(CheckFunctionExists)
 INCLUDE(CheckSymbolExists)
 INCLUDE(CheckIncludeFile)
 INCLUDE(CheckTypeSize)
+INCLUDE(CMakePackageConfigHelpers)
 INCLUDE(GNUInstallDirs) # for CMAKE_INSTALL_LIBDIR
 
 CHECK_INCLUDE_FILE(dirent.h     HAVE_DIRENT_H)
@@ -734,7 +736,9 @@ IF(PCRE2_BUILD_PCRE2_8)
       VERSION ${LIBPCRE2_8_VERSION}
       SOVERSION ${LIBPCRE2_8_SOVERSION})
     TARGET_COMPILE_DEFINITIONS(pcre2-8-static PUBLIC PCRE2_STATIC)
-    TARGET_INCLUDE_DIRECTORIES(pcre2-8-static PUBLIC ${PROJECT_BINARY_DIR})
+    TARGET_INCLUDE_DIRECTORIES(pcre2-8-static PUBLIC
+      $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}>
+      $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>)
     IF(REQUIRE_PTHREAD)
         TARGET_LINK_LIBRARIES(pcre2-8-static Threads::Threads)
     ENDIF(REQUIRE_PTHREAD)
@@ -747,7 +751,9 @@ IF(PCRE2_BUILD_PCRE2_8)
       VERSION ${LIBPCRE2_POSIX_VERSION}
       SOVERSION ${LIBPCRE2_POSIX_SOVERSION})
     TARGET_LINK_LIBRARIES(pcre2-posix-static pcre2-8-static)
-    TARGET_INCLUDE_DIRECTORIES(pcre2-posix-static PUBLIC ${PROJECT_BINARY_DIR})
+    TARGET_INCLUDE_DIRECTORIES(pcre2-posix-static PUBLIC
+      $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}>
+      $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>)
     set(targets ${targets} pcre2-posix-static)
 
     IF(MSVC)
@@ -764,7 +770,9 @@ IF(PCRE2_BUILD_PCRE2_8)
 
   IF(BUILD_SHARED_LIBS)
     ADD_LIBRARY(pcre2-8-shared SHARED ${PCRE2_HEADERS} ${PCRE2_SOURCES} ${PROJECT_BINARY_DIR}/config.h)
-    TARGET_INCLUDE_DIRECTORIES(pcre2-8-shared PUBLIC ${PROJECT_BINARY_DIR})
+    TARGET_INCLUDE_DIRECTORIES(pcre2-8-shared PUBLIC
+      $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}>
+      $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>)
     SET_TARGET_PROPERTIES(pcre2-8-shared PROPERTIES
       COMPILE_DEFINITIONS PCRE2_CODE_UNIT_WIDTH=8
       MACHO_COMPATIBILITY_VERSION "${LIBPCRE2_8_MACHO_COMPATIBILITY_VERSION}"
@@ -778,7 +786,9 @@ IF(PCRE2_BUILD_PCRE2_8)
     set(targets ${targets} pcre2-8-shared)
 
     ADD_LIBRARY(pcre2-posix-shared SHARED ${PCRE2POSIX_HEADERS} ${PCRE2POSIX_SOURCES})
-    TARGET_INCLUDE_DIRECTORIES(pcre2-posix-shared PUBLIC ${PROJECT_BINARY_DIR})
+    TARGET_INCLUDE_DIRECTORIES(pcre2-posix-shared PUBLIC
+      $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}>
+      $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>)
     SET_TARGET_PROPERTIES(pcre2-posix-shared PROPERTIES
       COMPILE_DEFINITIONS PCRE2_CODE_UNIT_WIDTH=8
       MACHO_COMPATIBILITY_VERSION "${LIBPCRE2_POSIX_MACHO_COMPATIBILITY_VERSION}"
@@ -816,7 +826,9 @@ ENDIF(PCRE2_BUILD_PCRE2_8)
 IF(PCRE2_BUILD_PCRE2_16)
   IF(BUILD_STATIC_LIBS)
     ADD_LIBRARY(pcre2-16-static STATIC ${PCRE2_HEADERS} ${PCRE2_SOURCES} ${PROJECT_BINARY_DIR}/config.h)
-    TARGET_INCLUDE_DIRECTORIES(pcre2-16-static PUBLIC ${PROJECT_BINARY_DIR})
+    TARGET_INCLUDE_DIRECTORIES(pcre2-16-static PUBLIC
+      $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}>
+      $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>)
     SET_TARGET_PROPERTIES(pcre2-16-static PROPERTIES UNITY_BUILD OFF
       COMPILE_DEFINITIONS PCRE2_CODE_UNIT_WIDTH=16
       MACHO_COMPATIBILITY_VERSION "${LIBPCRE2_32_MACHO_COMPATIBILITY_VERSION}"
@@ -841,7 +853,9 @@ IF(PCRE2_BUILD_PCRE2_16)
 
   IF(BUILD_SHARED_LIBS)
     ADD_LIBRARY(pcre2-16-shared SHARED ${PCRE2_HEADERS} ${PCRE2_SOURCES} ${PROJECT_BINARY_DIR}/config.h)
-    TARGET_INCLUDE_DIRECTORIES(pcre2-16-shared PUBLIC ${PROJECT_BINARY_DIR})
+    TARGET_INCLUDE_DIRECTORIES(pcre2-16-shared PUBLIC
+      $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}>
+      $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>)
     SET_TARGET_PROPERTIES(pcre2-16-shared PROPERTIES UNITY_BUILD OFF
       COMPILE_DEFINITIONS PCRE2_CODE_UNIT_WIDTH=16
       MACHO_COMPATIBILITY_VERSION "${LIBPCRE2_32_MACHO_COMPATIBILITY_VERSION}"
@@ -878,7 +892,9 @@ ENDIF(PCRE2_BUILD_PCRE2_16)
 IF(PCRE2_BUILD_PCRE2_32)
   IF(BUILD_STATIC_LIBS)
     ADD_LIBRARY(pcre2-32-static STATIC ${PCRE2_HEADERS} ${PCRE2_SOURCES} ${PROJECT_BINARY_DIR}/config.h)
-    TARGET_INCLUDE_DIRECTORIES(pcre2-32-static PUBLIC ${PROJECT_BINARY_DIR})
+    TARGET_INCLUDE_DIRECTORIES(pcre2-32-static PUBLIC
+      $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}>
+      $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>)
     SET_TARGET_PROPERTIES(pcre2-32-static PROPERTIES UNITY_BUILD OFF
       COMPILE_DEFINITIONS PCRE2_CODE_UNIT_WIDTH=32
       MACHO_COMPATIBILITY_VERSION "${LIBPCRE2_32_MACHO_COMPATIBILITY_VERSION}"
@@ -903,7 +919,9 @@ IF(PCRE2_BUILD_PCRE2_32)
 
   IF(BUILD_SHARED_LIBS)
     ADD_LIBRARY(pcre2-32-shared SHARED ${PCRE2_HEADERS} ${PCRE2_SOURCES} ${PROJECT_BINARY_DIR}/config.h)
-    TARGET_INCLUDE_DIRECTORIES(pcre2-32-shared PUBLIC ${PROJECT_BINARY_DIR})
+    TARGET_INCLUDE_DIRECTORIES(pcre2-32-shared PUBLIC
+      $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}>
+      $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>)
     SET_TARGET_PROPERTIES(pcre2-32-shared PROPERTIES UNITY_BUILD OFF
       COMPILE_DEFINITIONS PCRE2_CODE_UNIT_WIDTH=32
       MACHO_COMPATIBILITY_VERSION "${LIBPCRE2_32_MACHO_COMPATIBILITY_VERSION}"
@@ -1105,9 +1123,13 @@ ENDIF(PCRE2_BUILD_TESTS)
 SET(CMAKE_INSTALL_ALWAYS 1)
 
 INSTALL(TARGETS ${targets}
-        RUNTIME DESTINATION bin
+        EXPORT pcre2-targets
+        RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
         LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
         ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR})
+INSTALL(EXPORT pcre2-targets
+        DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/pcre2
+        NAMESPACE pcre2::)
 INSTALL(FILES ${pkg_config_files} DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)
 INSTALL(FILES "${CMAKE_CURRENT_BINARY_DIR}/pcre2-config"
   DESTINATION bin
@@ -1119,11 +1141,12 @@ INSTALL(FILES ${PCRE2_HEADERS} ${PCRE2POSIX_HEADERS} DESTINATION include)
 # CMake config files.
 set(PCRE2_CONFIG_IN  ${CMAKE_CURRENT_SOURCE_DIR}/cmake/pcre2-config.cmake.in)
 set(PCRE2_CONFIG_OUT ${CMAKE_CURRENT_BINARY_DIR}/cmake/pcre2-config.cmake)
-configure_file(${PCRE2_CONFIG_IN} ${PCRE2_CONFIG_OUT} @ONLY)
-set(PCRE2_CONFIG_VERSION_IN  ${CMAKE_CURRENT_SOURCE_DIR}/cmake/pcre2-config-version.cmake.in)
+configure_package_config_file(${PCRE2_CONFIG_IN} ${PCRE2_CONFIG_OUT} INSTALL_DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/pcre2)
 set(PCRE2_CONFIG_VERSION_OUT ${CMAKE_CURRENT_BINARY_DIR}/cmake/pcre2-config-version.cmake)
-configure_file(${PCRE2_CONFIG_VERSION_IN} ${PCRE2_CONFIG_VERSION_OUT} @ONLY)
-install(FILES ${PCRE2_CONFIG_OUT} ${PCRE2_CONFIG_VERSION_OUT} DESTINATION cmake)
+write_basic_package_version_file(${PCRE2_CONFIG_VERSION_OUT}
+                                 VERSION ${PCRE2_MAJOR}.${PCRE2_MINOR}.0
+                                 COMPATIBILITY SameMajorVersion)
+install(FILES ${PCRE2_CONFIG_OUT} ${PCRE2_CONFIG_VERSION_OUT} DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/pcre2)
 
 FILE(GLOB html ${PROJECT_SOURCE_DIR}/doc/html/*.html)
 FILE(GLOB man1 ${PROJECT_SOURCE_DIR}/doc/*.1)

diff --git a/cmake/pcre2-config-version.cmake.in b/cmake/pcre2-config-version.cmake.in
diff --git a/cmake/pcre2-config.cmake.in b/cmake/pcre2-config.cmake.in
@@ -5,11 +5,17 @@
 #
 # Static vs. shared
 # -----------------
-# To make use of the static library instead of the shared one, one needs
+# To force using the static library instead of the shared one, one needs
 # to set the variable PCRE2_USE_STATIC_LIBS to ON before calling find_package.
+# If the variable is not set, the static library will be used if only that has
+# been built, otherwise the shared library will be used.
+#
+# The following components are supported: 8BIT, 16BIT, 32BIT and POSIX.
+# They used to be required but not anymore; all available targets will
+# be defined regardless of the requested components.
 # Example:
 #   set(PCRE2_USE_STATIC_LIBS ON)
-#   find_package(PCRE2 CONFIG COMPONENTS 8BIT)
+#   find_package(PCRE2 CONFIG)
 #
 # This will define the following variables:
 #
@@ -23,70 +29,42 @@
 #   PCRE2::32BIT - The 32 bit PCRE2 library.
 #   PCRE2::POSIX - The POSIX PCRE2 library.
 
-set(PCRE2_NON_STANDARD_LIB_PREFIX @NON_STANDARD_LIB_PREFIX@)
-set(PCRE2_NON_STANDARD_LIB_SUFFIX @NON_STANDARD_LIB_SUFFIX@)
-set(PCRE2_8BIT_NAME pcre2-8)
-set(PCRE2_16BIT_NAME pcre2-16)
-set(PCRE2_32BIT_NAME pcre2-32)
-set(PCRE2_POSIX_NAME pcre2-posix)
-find_path(PCRE2_INCLUDE_DIR NAMES pcre2.h DOC "PCRE2 include directory")
-if (PCRE2_USE_STATIC_LIBS)
-  if (MSVC)
-    set(PCRE2_8BIT_NAME pcre2-8-static)
-    set(PCRE2_16BIT_NAME pcre2-16-static)
-    set(PCRE2_32BIT_NAME pcre2-32-static)
-    set(PCRE2_POSIX_NAME pcre2-posix-static)
-  endif ()
+@PACKAGE_INIT@
 
-  set(PCRE2_PREFIX ${CMAKE_STATIC_LIBRARY_PREFIX})
-  set(PCRE2_SUFFIX ${CMAKE_STATIC_LIBRARY_SUFFIX})
-else ()
-  set(PCRE2_PREFIX ${CMAKE_SHARED_LIBRARY_PREFIX})
-  if (MINGW AND PCRE2_NON_STANDARD_LIB_PREFIX)
-    set(PCRE2_PREFIX "")
-  endif ()
+include(CMakeFindDependencyMacro)
+if("@REQUIRE_PTHREAD@") # REQUIRE_PTHREAD
+  find_dependency(Threads)
+endif()
 
-  set(PCRE2_SUFFIX ${CMAKE_SHARED_LIBRARY_SUFFIX})
-  if (MINGW AND PCRE2_NON_STANDARD_LIB_SUFFIX)
-    set(PCRE2_SUFFIX "-0.dll")
-  endif ()
-endif ()
-find_library(PCRE2_8BIT_LIBRARY NAMES ${PCRE2_PREFIX}${PCRE2_8BIT_NAME}${PCRE2_SUFFIX} ${PCRE2_PREFIX}${PCRE2_8BIT_NAME}d${PCRE2_SUFFIX} DOC "8 bit PCRE2 library")
-find_library(PCRE2_16BIT_LIBRARY NAMES ${PCRE2_PREFIX}${PCRE2_16BIT_NAME}${PCRE2_SUFFIX} ${PCRE2_PREFIX}${PCRE2_8BIT_NAME}d${PCRE2_SUFFIX} DOC "16 bit PCRE2 library")
-find_library(PCRE2_32BIT_LIBRARY NAMES ${PCRE2_PREFIX}${PCRE2_32BIT_NAME}${PCRE2_SUFFIX} ${PCRE2_PREFIX}${PCRE2_8BIT_NAME}d${PCRE2_SUFFIX} DOC "32 bit PCRE2 library")
-find_library(PCRE2_POSIX_LIBRARY NAMES ${PCRE2_PREFIX}${PCRE2_POSIX_NAME}${PCRE2_SUFFIX} ${PCRE2_PREFIX}${PCRE2_8BIT_NAME}d${PCRE2_SUFFIX} DOC "8 bit POSIX PCRE2 library")
-unset(PCRE2_NON_STANDARD_LIB_PREFIX)
-unset(PCRE2_NON_STANDARD_LIB_SUFFIX)
-unset(PCRE2_8BIT_NAME)
-unset(PCRE2_16BIT_NAME)
-unset(PCRE2_32BIT_NAME)
-unset(PCRE2_POSIX_NAME)
+include("${CMAKE_CURRENT_LIST_DIR}/pcre2-targets.cmake")
 
 # Set version
-if (PCRE2_INCLUDE_DIR)
-  set(PCRE2_VERSION "@PCRE2_MAJOR@.@PCRE2_MINOR@.0")
-endif ()
+set(PCRE2_VERSION "@PCRE2_MAJOR@.@PCRE2_MINOR@.0")
 
-# Which components have been found.
-if (PCRE2_8BIT_LIBRARY)
-  set(PCRE2_8BIT_FOUND TRUE)
-endif ()
-if (PCRE2_16BIT_LIBRARY)
-  set(PCRE2_16BIT_FOUND TRUE)
-endif ()
-if (PCRE2_32BIT_LIBRARY)
-  set(PCRE2_32BIT_FOUND TRUE)
-endif ()
-if (PCRE2_POSIX_LIBRARY)
-  set(PCRE2_POSIX_FOUND TRUE)
-endif ()
-
-# Check if at least one component has been specified.
-list(LENGTH PCRE2_FIND_COMPONENTS PCRE2_NCOMPONENTS)
-if (PCRE2_NCOMPONENTS LESS 1)
-  message(FATAL_ERROR "No components have been specified. This is not allowed. Please, specify at least one component.")
-endif ()
-unset(PCRE2_NCOMPONENTS)
+# Chooses the linkage of the library to expose in the
+# unsuffixed edition of the target.
+macro(_pcre2_add_component_target component target)
+  # If the static library exists and either PCRE2_USE_STATIC_LIBS
+  # is defined, or the dynamic library does not exist, use the static library.
+  if(NOT TARGET PCRE2::${component})
+    if(TARGET pcre2::pcre2-${target}-static AND (PCRE2_USE_STATIC_LIBS OR NOT TARGET pcre2::pcre2-${target}-shared))
+      add_library(PCRE2::${component} ALIAS pcre2::pcre2-${target}-static)
+      set(PCRE2_${component}_FOUND TRUE)
+    # Otherwise use the dynamic library if it exists.
+    elseif(TARGET pcre2::pcre2-${target}-shared AND NOT PCRE2_USE_STATIC_LIBS)
+      add_library(PCRE2::${component} ALIAS pcre2::pcre2-${target}-shared)
+      set(PCRE2_${component}_FOUND TRUE)
+    endif()
+    if(PCRE2_${component}_FOUND)
+      get_target_property(PCRE2_${component}_LIBRARY PCRE2::${component} IMPORTED_LOCATION)
+      set(PCRE2_LIBRARIES ${PCRE2_LIBRARIES} ${PCRE2_${component}_LIBRARY})
+    endif()
+  endif()
+endmacro()
+_pcre2_add_component_target(8BIT 8)
+_pcre2_add_component_target(16BIT 16)
+_pcre2_add_component_target(32BIT 32)
+_pcre2_add_component_target(POSIX posix)
 
 # When POSIX component has been specified make sure that also 8BIT component is specified.
 set(PCRE2_8BIT_COMPONENT FALSE)
@@ -105,41 +83,5 @@ endif()
 unset(PCRE2_8BIT_COMPONENT)
 unset(PCRE2_POSIX_COMPONENT)
 
-include(FindPackageHandleStandardArgs)
-set(${CMAKE_FIND_PACKAGE_NAME}_CONFIG "${CMAKE_CURRENT_LIST_FILE}")
-find_package_handle_standard_args(PCRE2
-  FOUND_VAR PCRE2_FOUND
-  REQUIRED_VARS PCRE2_INCLUDE_DIR
-  HANDLE_COMPONENTS
-  VERSION_VAR PCRE2_VERSION
-  CONFIG_MODE
-)
-
-set(PCRE2_LIBRARIES)
-if (PCRE2_FOUND)
-  foreach(component ${PCRE2_FIND_COMPONENTS})
-    if (PCRE2_USE_STATIC_LIBS)
-      add_library(PCRE2::${component} STATIC IMPORTED)
-      target_compile_definitions(PCRE2::${component} INTERFACE PCRE2_STATIC)
-    else ()
-      add_library(PCRE2::${component} SHARED IMPORTED)
-    endif ()
-    set_target_properties(PCRE2::${component} PROPERTIES
-      IMPORTED_LOCATION "${PCRE2_${component}_LIBRARY}"
-      INTERFACE_INCLUDE_DIRECTORIES "${PCRE2_INCLUDE_DIR}"
-    )
-    if (component STREQUAL "POSIX")
-      set_target_properties(PCRE2::${component} PROPERTIES
-        INTERFACE_LINK_LIBRARIES "PCRE2::8BIT"
-        LINK_LIBRARIES "PCRE2::8BIT"
-      )
-    endif ()
-
-    set(PCRE2_LIBRARIES ${PCRE2_LIBRARIES} ${PCRE2_${component}_LIBRARY})
-    mark_as_advanced(PCRE2_${component}_LIBRARY)
-  endforeach()
-endif ()
-
-mark_as_advanced(
-  PCRE2_INCLUDE_DIR
-)
+# Check for required components.
+check_required_components("PCRE2")