Miscellaneous compatibility tweaks

* CMakeLists.txt: Retrieve SDL2 location using the sdl2-config utility
* CMakeLists.txt: Build for Mac OS 10.4 minimum
* .gitignore: ignore .DS_Store (macOS folder metadata)
* Supply strnlen() if necessary (missing on older macOS versions)
* Allow running without joystick support if SDL was built without it

.gitignore

@@ -66,6 +66,9 @@ build/
 # Windows thumbnail cache
 Thumbs.db
 
+# macOS folder metadata
+.DS_Store
+
 # The desktop file has to be recreated from the template.
 src/SDLPoP.desktop
 

src/CMakeLists.txt

@@ -16,10 +16,8 @@ set(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${SDLPoP_SOURCE_DIR}/..")
 
 #set(SDL2 "/usr/local/Cellar/sdl2/2.0.5")
 
-if (NOT(WIN32) AND (DEFINED SDL2))
-    include_directories(${SDL2}/include)
-    link_directories(${SDL2}/lib)
-endif()
+# If you don't specify the location of SDL2, this script will try to guess the location,
+# or retrieve it using the sdl2-config utility.
 
 if (WIN32)
     if (MSVC)
@@ -49,6 +47,16 @@ if (WIN32)
 
     include_directories(${SDL2}/${SDL2_ARCH}/include)
     link_directories(${SDL2}/${SDL2_ARCH}/lib)
+else()
+    if (DEFINED SDL2)
+        include_directories(${SDL2}/include)
+        link_directories(${SDL2}/lib)
+    else()
+        execute_process(COMMAND sdl2-config --prefix OUTPUT_VARIABLE SDL2_PREFIX)
+        string(STRIP ${SDL2_PREFIX} SDL2_PREFIX)
+        include_directories(${SDL2_PREFIX}/include)
+        link_directories(${SDL2_PREFIX}/lib)
+    endif()
 endif()
 
 set(SOURCE_FILES
@@ -89,7 +97,7 @@ else()
 
     set(MACOSX_BUNDLE_ICON_FILE            "icon.icns")
     set_source_files_properties(${MACOSX_BUNDLE_ICON_FILE} PROPERTIES MACOSX_PACKAGE_LOCATION Resources)
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mmacosx-version-min=10.6")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mmacosx-version-min=10.4")
     set(CMAKE_C_LINK_FLAGS "${CMAKE_C_LINK_FLAGS} -headerpad_max_install_names")
     add_executable(prince MACOSX_BUNDLE ${SOURCE_FILES} ${MACOSX_BUNDLE_ICON_FILE})
     set_target_properties(prince PROPERTIES MACOSX_BUNDLE_INFO_PLIST ${CMAKE_SOURCE_DIR}/Info.plist)

src/common.h

@@ -67,6 +67,15 @@ extern "C" {
 #define ABS(x) ((x)<0?-(x):(x))
 #endif
 
+#if defined(__APPLE__) && !defined(strnlen)
+// Use this if strnlen is missing.
+static inline size_t strnlen(const char *str, size_t max)
+{
+	const char *end = memchr (str, 0, max);
+	return end ? (size_t)(end - str) : max;
+}
+#endif
+
 #ifdef __cplusplus
 }
 #endif

src/data.h

@@ -558,6 +558,7 @@ extern SDL_Texture* texture_fuzzy;
 extern SDL_Texture* texture_blurry;
 extern SDL_Texture* target_texture;
 
+extern bool is_joyst_supported;
 extern SDL_GameController* sdl_controller_ INIT( = 0 );
 extern SDL_Joystick* sdl_joystick_; // in case our joystick is not compatible with SDL_GameController
 extern byte using_sdl_joystick_interface;

src/seg009.c

@@ -671,6 +671,7 @@ void __pascal far draw_image_transp(image_type far *image,image_type far *mask,i
 // seg009:157E
 int __pascal far set_joy_mode() {
 	// stub
+	if (!is_joyst_supported) return;
 	if (SDL_NumJoysticks() < 1) {
 		is_joyst_mode = 0;
 	} else {
@@ -696,7 +697,6 @@ int __pascal far set_joy_mode() {
 	} else {
 		sdl_haptic = NULL;
 	}
-
 	is_keyboard_mode = !is_joyst_mode;
 	return is_joyst_mode;
 }
@@ -1738,25 +1738,11 @@ void init_digi() {
 	// Open the audio device. Called once.
 	//printf("init_digi(): called\n");
 
-	SDL_AudioFormat desired_audioformat;
-	SDL_version version;
-	SDL_GetVersion(&version);
-	//printf("SDL Version = %d.%d.%d\n", version.major, version.minor, version.patch);
-	if (version.major <= 2 && version.minor <= 0 && version.patch <= 3) {
-		// In versions before 2.0.4, 16-bit audio samples don't work properly (the sound becomes garbled).
-		// See: https://bugzilla.libsdl.org/show_bug.cgi?id=2389
-		// Workaround: set the audio format to 8-bit, if we are linking against an older SDL2 version.
-		desired_audioformat = AUDIO_U8;
-		printf("Your SDL.dll is older than 2.0.4. Using 8-bit audio format to work around resampling bug.");
-	} else {
-		desired_audioformat = AUDIO_S16SYS;
-	}
-
 	SDL_AudioSpec *desired;
 	desired = (SDL_AudioSpec *)malloc(sizeof(SDL_AudioSpec));
 	memset(desired, 0, sizeof(SDL_AudioSpec));
 	desired->freq = digi_samplerate; //buffer->digi.sample_rate;
-	desired->format = desired_audioformat;
+	desired->format = AUDIO_S16SYS;
 	desired->channels = 2;
 	desired->samples = 1024;
 	desired->callback = audio_callback;
@@ -2128,11 +2114,16 @@ void __pascal far set_gr_mode(byte grmode) {
 #ifdef SDL_HINT_WINDOWS_DISABLE_THREAD_NAMING
 	SDL_SetHint(SDL_HINT_WINDOWS_DISABLE_THREAD_NAMING, "1");
 #endif
-	if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER | SDL_INIT_NOPARACHUTE |
-	             SDL_INIT_GAMECONTROLLER | SDL_INIT_HAPTIC ) != 0) {
+	Uint32 init_flags = SDL_INIT_VIDEO | SDL_INIT_TIMER | SDL_INIT_NOPARACHUTE;
+	if (SDL_Init(init_flags) != 0) {
 		sdlperror("SDL_Init");
 		quit(1);
 	}
+
+	is_joyst_supported = (SDL_InitSubSystem(SDL_INIT_GAMECONTROLLER | SDL_INIT_HAPTIC) == 0);
+	if (!is_joyst_supported) {
+		sdlperror("SDL_InitSubSystem");
+	}
 
 	//SDL_EnableUNICODE(1); //deprecated
 	Uint32 flags = 0;
@@ -2940,6 +2931,7 @@ void process_events() {
 #endif
 				break;
 			case SDL_CONTROLLERAXISMOTION:
+				if (!is_joyst_supported) break;
 				if (event.caxis.axis < 6) {
 					joy_axis[event.caxis.axis] = event.caxis.value;
 
@@ -2952,6 +2944,7 @@ void process_events() {
 				}
 				break;
 			case SDL_CONTROLLERBUTTONDOWN:
+				if (!is_joyst_supported) break;
 #ifdef USE_AUTO_INPUT_MODE
 				if (!is_joyst_mode) {
 					is_joyst_mode = 1;
@@ -2983,6 +2976,7 @@ void process_events() {
 				}
 				break;
 			case SDL_CONTROLLERBUTTONUP:
+				if (!is_joyst_supported) break;
 				switch (event.cbutton.button)
 				{
 					case SDL_CONTROLLER_BUTTON_DPAD_LEFT:  joy_hat_states[0] = 0; break; // left
@@ -3001,6 +2995,7 @@ void process_events() {
 			case SDL_JOYBUTTONDOWN:
 			case SDL_JOYBUTTONUP:
 			case SDL_JOYAXISMOTION:
+				if (!is_joyst_supported) break;
 				// Only handle the event if the joystick is incompatible with the SDL_GameController interface.
 				// (Otherwise it will interfere with the normal action of the SDL_GameController API.)
 				if (!using_sdl_joystick_interface) {
@@ -3035,7 +3030,6 @@ void process_events() {
 					else if (event.jbutton.button == SDL_JOYSTICK_BUTTON_X)   joy_X_button_state = 0;    // X (shift)
 				}
 				break;
-
 			case SDL_TEXTINPUT:
 				last_text_input = event.text.text[0]; // UTF-8 formatted char text input
 				break;