CMake: Use targets for all optionally-external dependencies

Externals/LZO/CMakeLists.txt

@@ -7,3 +7,4 @@ target_include_directories(lzo2
 PUBLIC
   ${CMAKE_CURRENT_SOURCE_DIR}
 )
+add_library(LZO::LZO ALIAS lzo2)

Externals/SDL/CMakeLists.txt

@@ -0,0 +1,17 @@
+option(SDL2_DISABLE_SDL2MAIN "" ON)
+option(SDL2_DISABLE_INSTALL "" ON)
+option(SDL2_DISABLE_UNINSTALL "" ON)
+set(SDL_SHARED OFF)
+set(SDL_SHARED_ENABLED_BY_DEFAULT OFF)
+set(SDL_STATIC ON)
+set(SDL_STATIC_ENABLED_BY_DEFAULT ON)
+set(SDL_TEST OFF)
+set(SDL_TEST_ENABLED_BY_DEFAULT OFF)
+set(OPT_DEF_LIBC ON)
+add_subdirectory(SDL)
+if (TARGET SDL2)
+  dolphin_disable_warnings_msvc(SDL2)
+endif()
+if (TARGET SDL2-static)
+  dolphin_disable_warnings_msvc(SDL2-static)
+endif()

Externals/SFML/CMakeLists.txt

@@ -1,5 +1,3 @@
-include_directories(BEFORE include src)
-
 set(SRC_NETWORK
 	src/SFML/Network/Http.cpp
 	src/SFML/Network/IPAddress.cpp
@@ -23,7 +21,11 @@ set(SRC_SYSTEM
 	src/SFML/System/Time.cpp
 )
 
-add_library(sfml-network ${SRC_NETWORK})
-add_library(sfml-system ${SRC_SYSTEM})
+add_library(sfml-network STATIC ${SRC_NETWORK})
+add_library(sfml-system STATIC ${SRC_SYSTEM})
+target_compile_definitions(sfml-system PUBLIC SFML_STATIC)
+target_include_directories(sfml-system PUBLIC include PRIVATE src)
+target_include_directories(sfml-network PUBLIC include PRIVATE src)
+target_link_libraries(sfml-network PUBLIC sfml-system)
 dolphin_disable_warnings_msvc(sfml-network)
 dolphin_disable_warnings_msvc(sfml-system)

Externals/cubeb/CMakeLists.txt

@@ -352,3 +352,4 @@ if(USE_AUDIOUNIT AND USE_AUDIOUNIT_RUST)
     debug "${PROJECT_SOURCE_DIR}/cubeb/src/cubeb-coreaudio-rs/target/debug/libcubeb_coreaudio.a"
     optimized "${PROJECT_SOURCE_DIR}/cubeb/src/cubeb-coreaudio-rs/target/release/libcubeb_coreaudio.a")
 endif()
+add_library(cubeb::cubeb ALIAS cubeb)

Externals/curl/lib/CMakeLists.txt

@@ -4,8 +4,6 @@ else()
     add_definitions(-DHAVE_CONFIG_H)
 endif()
 
-include_directories(.)
-
 file(GLOB SRCS *.c vauth/*.c vtls/*.c)
 add_library(
   curl
@@ -14,5 +12,7 @@ add_library(
   )
 dolphin_disable_warnings_msvc(curl)
 
-target_link_libraries(curl ${MBEDTLS_LIBRARIES} zlibstatic)
+target_include_directories(curl PRIVATE . INTERFACE ../include)
+target_link_libraries(curl MbedTLS::mbedtls zlibstatic)
 target_compile_definitions(curl PUBLIC CURL_STATICLIB PRIVATE CURL_DISABLE_LDAP)
+add_library(CURL::libcurl ALIAS curl)

Externals/enet/CMakeLists.txt

@@ -59,8 +59,6 @@ if(HAS_SOCKLEN_T)
     add_definitions(-DHAS_SOCKLEN_T=1)
 endif()
 
-include_directories(${PROJECT_SOURCE_DIR}/include)
-
 set(INCLUDE_FILES_PREFIX include/enet)
 set(INCLUDE_FILES
     ${INCLUDE_FILES_PREFIX}/callbacks.h
@@ -92,8 +90,10 @@ add_library(enet STATIC
     ${INCLUDE_FILES}
     ${SOURCE_FILES}
 )
+target_include_directories(enet PUBLIC include)
 
 dolphin_disable_warnings_msvc(enet)
+add_library(enet::enet ALIAS enet)
 
 if (MINGW)
     target_link_libraries(enet winmm ws2_32)

Externals/libspng/CMakeLists.txt

@@ -2,8 +2,9 @@ cmake_minimum_required(VERSION 3.0)
 
 project(spng C)
 
-add_library(spng STATIC ${CMAKE_CURRENT_LIST_DIR}/libspng/spng/spng.c)
+add_library(spng STATIC libspng/spng/spng.c)
 target_compile_definitions(spng PUBLIC SPNG_STATIC)
 target_link_libraries(spng PUBLIC ZLIB::ZLIB)
-target_include_directories(spng PUBLIC ${CMAKE_CURRENT_LIST_DIR}/libspng/spng/)
+target_include_directories(spng PUBLIC libspng/spng)
 dolphin_disable_warnings_msvc(spng)
+add_library(spng::spng ALIAS spng)

Externals/libusb/CMakeLists.txt

@@ -125,3 +125,4 @@ check_include_files(sys/timerfd.h HAVE_TIMERFD)
 check_include_files(unistd.h HAVE_UNISTD_H)
 
 configure_file(config.h.in config.h)
+add_library(LibUSB::LibUSB ALIAS usb)

Externals/mbedtls/library/CMakeLists.txt

@@ -222,6 +222,7 @@ if(USE_SHARED_MBEDTLS_LIBRARY)
 endif(USE_SHARED_MBEDTLS_LIBRARY)
 
 foreach(target IN LISTS target_libraries)
+    add_library(MbedTLS::${target} ALIAS ${target})  # add_subdirectory support
     # Include public header files from /include and other directories
     # declared by /3rdparty/**/CMakeLists.txt. Include private header files
     # from /library and others declared by /3rdparty/**/CMakeLists.txt.

Externals/minizip/CMakeLists.txt

@@ -67,4 +67,4 @@ endif()
 
 target_link_libraries(minizip PUBLIC ZLIB::ZLIB)
 
-add_library(minizip-ng ALIAS minizip)
+add_library(minizip::minizip ALIAS minizip)