Export CMake targets to the build tree

Properly export Vorbis targets when added via `add_subdirectory()`.

Author: evpobr

CMakeLists.txt

@@ -62,7 +62,9 @@ message(STATUS "Configuring ${PROJECT_NAME} ${PROJECT_VERSION}")
 check_library_exists(m floor "" HAVE_LIBM)
 
 # Find ogg dependency
-find_package(Ogg REQUIRED)
+if(NOT TARGET Ogg::ogg)
+    find_package(Ogg REQUIRED)
+endif()
 
 add_subdirectory(lib)
 

cmake/VorbisConfig.cmake.in

@@ -1,7 +1,9 @@
 @PACKAGE_INIT@
 
 include(CMakeFindDependencyMacro)
-find_dependency(Ogg REQUIRED)
+if(NOT TARGET Ogg::ogg)
+    find_dependency(Ogg REQUIRED)
+endif()
 
 include(${CMAKE_CURRENT_LIST_DIR}/VorbisTargets.cmake)
 

lib/CMakeLists.txt

@@ -78,6 +78,10 @@ if (NOT BUILD_FRAMEWORK)
     add_library(vorbisenc ${VORBISENC_SOURCES})
     add_library(vorbisfile ${VORBISFILE_SOURCES})
 
+    add_library(Vorbis::vorbis ALIAS vorbis)
+    add_library(Vorbis::vorbisenc ALIAS vorbisenc)
+    add_library(Vorbis::vorbisfile ALIAS vorbisfile)
+
     get_version_info(VORBIS_VERSION_INFO "V_LIB_CURRENT" "V_LIB_AGE" "V_LIB_REVISION")
     set_target_properties(vorbis PROPERTIES SOVERSION ${VORBIS_VERSION_INFO})
     get_version_info(VORBISENC_VERSION_INFO "VE_LIB_CURRENT" "VE_LIB_AGE" "VE_LIB_REVISION")
@@ -121,6 +125,7 @@ if (NOT BUILD_FRAMEWORK)
         ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
         FRAMEWORK DESTINATION ${CMAKE_INSTALL_LIBDIR}
     )
+    export(EXPORT VorbisTargets NAMESPACE Vorbis:: FILE VorbisTargets.cmake)
 
     if(INSTALL_CMAKE_PACKAGE_MODULE)
 
@@ -134,15 +139,15 @@ if (NOT BUILD_FRAMEWORK)
 
         include(CMakePackageConfigHelpers)
 
-        configure_package_config_file(${PROJECT_SOURCE_DIR}/cmake/VorbisConfig.cmake.in ${PROJECT_BINARY_DIR}/VorbisConfig.cmake
+        configure_package_config_file(${PROJECT_SOURCE_DIR}/cmake/VorbisConfig.cmake.in ${CMAKE_CURRENT_BINARY_DIR}/VorbisConfig.cmake
             INSTALL_DESTINATION ${CMAKE_INSTALL_CONFIGDIR}
         )
 
-        write_basic_package_version_file(${PROJECT_BINARY_DIR}/VorbisConfigVersion.cmake
+        write_basic_package_version_file(${CMAKE_CURRENT_BINARY_DIR}/VorbisConfigVersion.cmake
             COMPATIBILITY SameMajorVersion
         )
 
-        install(FILES ${PROJECT_BINARY_DIR}/VorbisConfig.cmake ${PROJECT_BINARY_DIR}/VorbisConfigVersion.cmake
+        install(FILES ${CMAKE_CURRENT_BINARY_DIR}/VorbisConfig.cmake ${CMAKE_CURRENT_BINARY_DIR}/VorbisConfigVersion.cmake
             DESTINATION ${CMAKE_INSTALL_CONFIGDIR}
         )