cmake: Add mini-SDL2 CMake project to test SDL2 prefixes

cmake/test/CMakeLists.txt

@@ -0,0 +1,91 @@
+# This cmake build script is meant for verifying the various CMake configuration script.
+
+cmake_minimum_required(VERSION 3.12)
+project(sdl_test LANGUAGES C)
+
+cmake_policy(SET CMP0074 NEW)
+
+# Override CMAKE_FIND_ROOT_PATH_MODE to allow search for SDL2 outside of sysroot
+set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE NEVER)
+
+include(FeatureSummary)
+
+option(TEST_SHARED "Test linking to shared SDL2 library" ON)
+add_feature_info("TEST_SHARED" TEST_SHARED "Test linking with shared library")
+
+option(TEST_STATIC "Test linking to static SDL2 libary" ON)
+add_feature_info("TEST_STATIC" TEST_STATIC "Test linking with static library")
+
+if(TEST_SHARED)
+    find_package(SDL2 REQUIRED CONFIG COMPONENTS SDL2)
+    if(EMSCRIPTEN OR (WIN32 AND NOT WINDOWS_STORE))
+        find_package(SDL2 REQUIRED CONFIG COMPONENTS SDL2main)
+    endif()
+    add_executable(gui-shared WIN32 main_gui.c)
+    if(TARGET SDL2::SDL2main)
+        target_link_libraries(gui-shared PRIVATE SDL2::SDL2main)
+    endif()
+    target_link_libraries(gui-shared PRIVATE SDL2::SDL2)
+    if(WIN32)
+        add_custom_command(TARGET gui-shared POST_BUILD
+            COMMAND ${CMAKE_COMMAND} -E copy_if_different "$<TARGET_FILE:SDL2::SDL2>" "$<TARGET_FILE_DIR:gui-shared>"
+        )
+    endif()
+
+    add_executable(gui-shared-vars WIN32 main_gui.c)
+    target_link_libraries(gui-shared-vars PRIVATE ${SDL2_LIBRARIES})
+    target_include_directories(gui-shared-vars PRIVATE ${SDL2_INCLUDE_DIRS})
+
+    add_executable(cli-shared main_cli.c)
+    target_link_libraries(cli-shared PRIVATE SDL2::SDL2)
+    if(WIN32)
+        add_custom_command(TARGET cli-shared POST_BUILD
+            COMMAND ${CMAKE_COMMAND} -E copy_if_different "$<TARGET_FILE:SDL2::SDL2>" "$<TARGET_FILE_DIR:cli-shared>"
+        )
+    endif()
+
+    # SDL2_LIBRARIES does not support creating a cli SDL2 application
+    # (it is possible that SDL2main is a stub, but we don't know for sure)
+    if(NOT TARGET SDL2::SDL2main)
+        add_executable(cli-shared-vars main_cli.c)
+        target_link_libraries(cli-shared-vars PRIVATE ${SDL2_LIBRARIES})
+        target_include_directories(cli-shared-vars PRIVATE ${SDL2_INCLUDE_DIRS})
+    endif()
+endif()
+
+if(TEST_STATIC)
+    find_package(SDL2 REQUIRED CONFIG COMPONENTS SDL2-static)
+    if(EMSCRIPTEN OR (WIN32 AND NOT WINDOWS_STORE))
+        find_package(SDL2 REQUIRED CONFIG COMPONENTS SDL2main)
+    endif()
+    add_executable(gui-static WIN32 main_gui.c)
+    if(TARGET SDL2::SDL2main)
+        target_link_libraries(gui-static PRIVATE SDL2::SDL2main)
+    endif()
+    target_link_libraries(gui-static PRIVATE SDL2::SDL2-static)
+
+    add_executable(gui-static-vars WIN32 main_gui.c)
+    target_link_libraries(gui-static-vars PRIVATE ${SDL2MAIN_LIBRARY} ${SDL2_STATIC_LIBRARIES})
+    target_include_directories(gui-static-vars PRIVATE ${SDL2_INCLUDE_DIRS})
+
+    add_executable(cli-static main_cli.c)
+    target_link_libraries(cli-static PRIVATE SDL2::SDL2-static)
+
+    # SDL2_LIBRARIES does not support creating a cli SDL2 application (when SDL2::SDL2main is available)
+    # (it is possible that SDL2main is a stub, but we don't know for sure)
+    if(NOT TARGET SDL2::SDL2main)
+        add_executable(cli-static-vars main_cli.c)
+        target_link_libraries(cli-static-vars PRIVATE ${SDL2_STATIC_LIBRARIES})
+        target_include_directories(cli-static-vars PRIVATE ${SDL2_INCLUDE_DIRS})
+    endif()
+endif()
+
+message(STATUS "SDL2_PREFIX:            ${SDL2_PREFIX}")
+message(STATUS "SDL2_INCLUDE_DIR:       ${SDL2_INCLUDE_DIR}")
+message(STATUS "SDL2_INCLUDE_DIRS:      ${SDL2_INCLUDE_DIRS}")
+message(STATUS "SDL2_LIBRARIES:         ${SDL2_LIBRARIES}")
+message(STATUS "SDL2_STATIC_LIBRARIES:  ${SDL2_STATIC_LIBRARIES}")
+message(STATUS "SDL2MAIN_LIBRARY:       ${SDL2MAIN_LIBRARY}")
+message(STATUS "SDL2TEST_LIBRARY:       ${SDL2TEST_LIBRARY}")
+
+feature_summary(WHAT ALL)

cmake/test/main_cli.c

@@ -0,0 +1,14 @@
+#define SDL_MAIN_HANDLED
+#include "SDL.h"
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+    SDL_SetMainReady();
+    if (SDL_Init(0) < 0) {
+        fprintf(stderr, "could not initialize sdl2: %s\n", SDL_GetError());
+        return 1;
+    }
+    SDL_Delay(100);
+    SDL_Quit();
+    return 0;
+}

cmake/test/main_gui.c

@@ -0,0 +1,28 @@
+#include "SDL.h"
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+    SDL_Window *window = NULL;
+    SDL_Surface *screenSurface = NULL;
+    if (SDL_Init(SDL_INIT_VIDEO) < 0) {
+        fprintf(stderr, "could not initialize sdl2: %s\n", SDL_GetError());
+        return 1;
+    }
+    window = SDL_CreateWindow(
+            "hello_sdl2",
+            SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
+            640, 480,
+            SDL_WINDOW_SHOWN
+    );
+    if (window == NULL) {
+        fprintf(stderr, "could not create window: %s\n", SDL_GetError());
+        return 1;
+    }
+    screenSurface = SDL_GetWindowSurface(window);
+    SDL_FillRect(screenSurface, NULL, SDL_MapRGB(screenSurface->format, 0xff, 0xff, 0xff));
+    SDL_UpdateWindowSurface(window);
+    SDL_Delay(100);
+    SDL_DestroyWindow(window);
+    SDL_Quit();
+    return 0;
+}