Removed the need for libSDL2main.a on Android, and separated JNI initialization out for other integrations

android-project/src/org/libsdl/app/SDLActivity.java

@@ -136,10 +136,11 @@ public class SDLActivity extends Activity {
     protected void onCreate(Bundle savedInstanceState) {
         Log.v(TAG, "Device: " + android.os.Build.DEVICE);
         Log.v(TAG, "Model: " + android.os.Build.MODEL);
-        Log.v(TAG, "onCreate(): " + mSingleton);
+        Log.v(TAG, "onCreate()");
         super.onCreate(savedInstanceState);
 
         SDLActivity.initialize();
+
         // So we can call stuff from static callbacks
         mSingleton = this;
 
@@ -179,18 +180,16 @@ public class SDLActivity extends Activity {
            return;
         }
 
-        // Set up the surface
-        mSurface = new SDLSurface(getApplication());
-
+        // Set up JNI
+        SDLActivity.nativeSetupJNI();
 
-        if(Build.VERSION.SDK_INT >= 16) {
+        if (Build.VERSION.SDK_INT >= 16) {
             mJoystickHandler = new SDLJoystickHandler_API16();
-        } else if(Build.VERSION.SDK_INT >= 12) {
+        } else if (Build.VERSION.SDK_INT >= 12) {
             mJoystickHandler = new SDLJoystickHandler_API12();
         } else {
             mJoystickHandler = new SDLJoystickHandler();
         }
-
         mHapticHandler = new SDLHapticHandler();
 
         if (Build.VERSION.SDK_INT >= 11) {
@@ -200,6 +199,9 @@ public class SDLActivity extends Activity {
             mClipboardHandler = new SDLClipboardHandler_Old();
         }
 
+        // Set up the surface
+        mSurface = new SDLSurface(getApplication());
+
         mLayout = new RelativeLayout(this);
         mLayout.addView(mSurface);
 
@@ -207,7 +209,6 @@ public class SDLActivity extends Activity {
         
         // Get filename from "Open with" of another application
         Intent intent = getIntent();
-
         if (intent != null && intent.getData() != null) {
             String filename = intent.getData().getPath();
             if (filename != null) {
@@ -309,6 +310,7 @@ public class SDLActivity extends Activity {
         }
 
         super.onDestroy();
+
         // Reset everything in case the user re opens the app
         SDLActivity.initialize();
     }
@@ -358,43 +360,42 @@ public class SDLActivity extends Activity {
 
         // Try a transition to resumed state
         if (mNextNativeState == NativeState.RESUMED) {
+            if (mIsSurfaceReady && mHasFocus && mIsResumedCalled) {
+                if (mSDLThread == null) {
+                    // This is the entry point to the C app.
+                    // Start up the C app thread and enable sensor input for the first time
+                    // FIXME: Why aren't we enabling sensor input at start?
+
+                    final Thread sdlThread = new Thread(new SDLMain(), "SDLThread");
+                    mSurface.enableSensor(Sensor.TYPE_ACCELEROMETER, true);
+                    sdlThread.start();
+
+                    // Set up a listener thread to catch when the native thread ends
+                    mSDLThread = new Thread(new Runnable() {
+                        @Override
+                        public void run() {
+                            try {
+                                sdlThread.join();
+                            } catch (Exception e) {
+                                // Ignore any exception
+                            } finally {
+                                // Native thread has finished
+                                if (!mExitCalledFromJava) {
+                                    handleNativeExit();
+                                }
+                            }
+                        }
+                    }, "SDLThreadListener");
 
-           if (mIsSurfaceReady && mHasFocus && mIsResumedCalled) {
-
-              if (mSDLThread == null) {
-                  // This is the entry point to the C app.
-                  // Start up the C app thread and enable sensor input for the first time
-
-                  final Thread sdlThread = new Thread(new SDLMain(), "SDLThread");
-                  mSurface.enableSensor(Sensor.TYPE_ACCELEROMETER, true);
-                  sdlThread.start();
-
-                  // Set up a listener thread to catch when the native thread ends
-                  mSDLThread = new Thread(new Runnable(){
-                      @Override
-                      public void run(){
-                          try {
-                              sdlThread.join();
-                          }
-                          catch(Exception e){}
-                          finally{
-                              // Native thread has finished
-                              if (! mExitCalledFromJava) {
-                                  handleNativeExit();
-                              }
-                          }
-                      }
-                  }, "SDLThreadListener");
-                  mSDLThread.start();
-              }
-
+                    mSDLThread.start();
+                }
 
-              nativeResume();
-              mSurface.handleResume();
-              mCurrentNativeState = mNextNativeState;
-          }
-          return;
-       }
+                nativeResume();
+                mSurface.handleResume();
+                mCurrentNativeState = mNextNativeState;
+            }
+            return;
+        }
     }
 
     /* The native thread has finished */
@@ -460,12 +461,14 @@ public class SDLActivity extends Activity {
                 break;
             case COMMAND_SET_KEEP_SCREEN_ON:
             {
-                Window window = ((Activity) context).getWindow();
-                if (window != null) {
-                    if ((msg.obj instanceof Integer) && (((Integer) msg.obj).intValue() != 0)) {
-                        window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
-                    } else {
-                        window.clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
+                if (context instanceof Activity) {
+                    Window window = ((Activity) context).getWindow();
+                    if (window != null) {
+                        if ((msg.obj instanceof Integer) && (((Integer) msg.obj).intValue() != 0)) {
+                            window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
+                        } else {
+                            window.clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
+                        }
                     }
                 }
                 break;
@@ -490,7 +493,8 @@ public class SDLActivity extends Activity {
     }
 
     // C functions we call
-    public static native int nativeInit(Object arguments);
+    public static native int nativeSetupJNI();
+    public static native int nativeRunMain(String library, String function, Object arguments);
     public static native void nativeLowMemory();
     public static native void nativeQuit();
     public static native void nativePause();
@@ -1208,15 +1212,25 @@ public class SDLActivity extends Activity {
 }
 
 /**
-    Simple nativeInit() runnable
+    Simple runnable to start the SDL application
 */
 class SDLMain implements Runnable {
     @Override
     public void run() {
         // Runs SDL_main()
-        SDLActivity.nativeInit(SDLActivity.mSingleton.getArguments());
+        String library;
+        String[] libraries = SDLActivity.mSingleton.getLibraries();
+        if (libraries.length > 0) {
+            library = "lib" + libraries[libraries.length - 1] + ".so";
+        } else {
+            library = "libmain.so";
+        }
+        String function = "SDL_main";
+
+        Log.v("SDL", "Running main function " + function + " from library " + library);
+        SDLActivity.nativeRunMain(library, function, SDLActivity.mSingleton.getArguments());
 
-        //Log.v("SDL", "SDL thread terminated");
+        Log.v("SDL", "Finished main function");
     }
 }
 
@@ -1251,7 +1265,7 @@ class SDLSurface extends SurfaceView implements SurfaceHolder.Callback,
         mDisplay = ((WindowManager)context.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
         mSensorManager = (SensorManager)context.getSystemService(Context.SENSOR_SERVICE);
 
-        if(Build.VERSION.SDK_INT >= 12) {
+        if (Build.VERSION.SDK_INT >= 12) {
             setOnGenericMotionListener(new SDLGenericMotionListener_API12());
         }
 
@@ -1964,8 +1978,8 @@ class SDLHapticHandler {
             SDLHaptic haptic = getHaptic(deviceIds[i]);
             if (haptic == null) {
                 InputDevice device = InputDevice.getDevice(deviceIds[i]);
-                Vibrator vib = device.getVibrator ();
-                if(vib.hasVibrator ()) {
+                Vibrator vib = device.getVibrator();
+                if (vib.hasVibrator()) {
                     haptic = new SDLHaptic();
                     haptic.device_id = deviceIds[i];
                     haptic.name = device.getName();

configure

@@ -1616,7 +1616,7 @@ Optional Features:
                           include OpenGL ES 1.1 support [[default=yes]]
   --enable-video-opengles2
                           include OpenGL ES 2.0 support [[default=yes]]
-  --enable-video-vulkan   include Vulkan surface support [[default=yes]]
+  --enable-video-vulkan   include Vulkan support [[default=yes]]
   --enable-libudev        enable libudev support [[default=yes]]
   --enable-dbus           enable D-Bus support [[default=yes]]
   --enable-ime            enable IME support [[default=yes]]
@@ -23641,7 +23641,6 @@ case "$host" in
                 ANDROID_CFLAGS="-DGL_GLEXT_PROTOTYPES"
                 CFLAGS="$CFLAGS $ANDROID_CFLAGS"
                 SDL_CFLAGS="$SDL_CFLAGS $ANDROID_CFLAGS"
-                SDL_LIBS="$SDL_LIBS -lSDL2main -Wl,-u,SDL_main_dummy"
                 EXTRA_CFLAGS="$EXTRA_CFLAGS $ANDROID_CFLAGS"
                 EXTRA_LDFLAGS="$EXTRA_LDFLAGS -ldl -lGLESv1_CM -lGLESv2 -llog -landroid"
                 SDLMAIN_SOURCES="$srcdir/src/main/android/*.c"

configure.in

@@ -3201,7 +3201,6 @@ case "$host" in
                 ANDROID_CFLAGS="-DGL_GLEXT_PROTOTYPES"
                 CFLAGS="$CFLAGS $ANDROID_CFLAGS"
                 SDL_CFLAGS="$SDL_CFLAGS $ANDROID_CFLAGS"
-                SDL_LIBS="$SDL_LIBS -lSDL2main -Wl,-u,SDL_main_dummy"
                 EXTRA_CFLAGS="$EXTRA_CFLAGS $ANDROID_CFLAGS"
                 EXTRA_LDFLAGS="$EXTRA_LDFLAGS -ldl -lGLESv1_CM -lGLESv2 -llog -landroid"
                 SDLMAIN_SOURCES="$srcdir/src/main/android/*.c"

include/SDL_main.h

@@ -107,7 +107,7 @@
 /**
  *  The prototype for the application's main() function
  */
-extern C_LINKAGE int SDL_main(int argc, char *argv[]);
+extern C_LINKAGE DECLSPEC int SDL_main(int argc, char *argv[]);
 
 
 #include "begin_code.h"

src/core/android/SDL_android.c

@@ -43,6 +43,7 @@
 #include <pthread.h>
 #include <sys/types.h>
 #include <unistd.h>
+#include <dlfcn.h>
 /* #define LOG_TAG "SDL_android" */
 /* #define LOGI(...)  __android_log_print(ANDROID_LOG_INFO,LOG_TAG,__VA_ARGS__) */
 /* #define LOGE(...)  __android_log_print(ANDROID_LOG_ERROR,LOG_TAG,__VA_ARGS__) */
@@ -58,6 +59,13 @@
 
 
 /* Java class SDLActivity */
+JNIEXPORT void JNICALL SDL_JAVA_INTERFACE(nativeSetupJNI)(
+        JNIEnv* mEnv, jclass cls);
+
+JNIEXPORT int JNICALL SDL_JAVA_INTERFACE(nativeRunMain)(
+        JNIEnv* env, jclass cls,
+        jstring library, jstring function, jobject array);
+
 JNIEXPORT void JNICALL SDL_JAVA_INTERFACE(onNativeDropFile)(
         JNIEnv* env, jclass jcls,
         jstring filename);
@@ -237,9 +245,9 @@ JNIEXPORT jint JNICALL JNI_OnLoad(JavaVM* vm, void* reserved)
 }
 
 /* Called before SDL_main() to initialize JNI bindings */
-JNIEXPORT void JNICALL SDL_Android_Init(JNIEnv* mEnv, jclass cls)
+JNIEXPORT void JNICALL SDL_JAVA_INTERFACE(nativeSetupJNI)(JNIEnv* mEnv, jclass cls)
 {
-    __android_log_print(ANDROID_LOG_INFO, "SDL", "SDL_Android_Init()");
+    __android_log_print(ANDROID_LOG_VERBOSE, "SDL", "nativeSetupJNI()");
 
     Android_JNI_SetupThread();
 
@@ -299,16 +307,95 @@ JNIEXPORT void JNICALL SDL_Android_Init(JNIEnv* mEnv, jclass cls)
        !midSetActivityTitle || !midSetOrientation || !midGetContext || !midInputGetInputDeviceIds ||
        !midSendMessage || !midShowTextInput || !midIsScreenKeyboardShown || 
        !midClipboardSetText || !midClipboardGetText || !midClipboardHasText) {
-        __android_log_print(ANDROID_LOG_WARN, "SDL", "SDL: Couldn't locate Java callbacks, check that they're named and typed correctly");
+        __android_log_print(ANDROID_LOG_WARN, "SDL", "Missing some Java callbacks, do you have the latest version of SDLActivity.java?");
     }
 
     fidSeparateMouseAndTouch = (*mEnv)->GetStaticFieldID(mEnv, mActivityClass, "mSeparateMouseAndTouch", "Z");
 
     if (!fidSeparateMouseAndTouch) {
-        __android_log_print(ANDROID_LOG_WARN, "SDL", "SDL: Couldn't locate Java static fields, check that they're named and typed correctly");
+        __android_log_print(ANDROID_LOG_WARN, "SDL", "Missing some Java static fields, do you have the latest version of SDLActivity.java?");
     }
 
-    __android_log_print(ANDROID_LOG_INFO, "SDL", "SDL_Android_Init() finished!");
+    SDL_SetMainReady();
+}
+
+/* SDL main function prototype */
+typedef int (*SDL_main_func)(int argc, char *argv[]);
+
+/* Start up the SDL app */
+JNIEXPORT int JNICALL SDL_JAVA_INTERFACE(nativeRunMain)(JNIEnv* env, jclass cls, jstring library, jstring function, jobject array)
+{
+    int status = -1;
+    const char *library_file;
+    void *library_handle;
+
+    library_file = (*env)->GetStringUTFChars(env, library, NULL);
+    library_handle = dlopen(library_file, RTLD_GLOBAL);
+    if (library_handle) {
+        const char *function_name;
+        SDL_main_func SDL_main;
+
+        function_name = (*env)->GetStringUTFChars(env, function, NULL);
+        SDL_main = (SDL_main_func)dlsym(library_handle, function_name);
+        if (SDL_main) {
+            int i;
+            int argc;
+            int len;
+            char **argv;
+
+            /* Prepare the arguments. */
+            len = (*env)->GetArrayLength(env, array);
+            argv = SDL_stack_alloc(char*, 1 + len + 1);
+            argc = 0;
+            /* Use the name "app_process" so PHYSFS_platformCalcBaseDir() works.
+               https://bitbucket.org/MartinFelis/love-android-sdl2/issue/23/release-build-crash-on-start
+             */
+            argv[argc++] = SDL_strdup("app_process");
+            for (i = 0; i < len; ++i) {
+                const char* utf;
+                char* arg = NULL;
+                jstring string = (*env)->GetObjectArrayElement(env, array, i);
+                if (string) {
+                    utf = (*env)->GetStringUTFChars(env, string, 0);
+                    if (utf) {
+                        arg = SDL_strdup(utf);
+                        (*env)->ReleaseStringUTFChars(env, string, utf);
+                    }
+                    (*env)->DeleteLocalRef(env, string);
+                }
+                if (!arg) {
+                    arg = SDL_strdup("");
+                }
+                argv[argc++] = arg;
+            }
+            argv[argc] = NULL;
+
+
+            /* Run the application. */
+            status = SDL_main(argc, argv);
+
+            /* Release the arguments. */
+            for (i = 0; i < argc; ++i) {
+                SDL_free(argv[i]);
+            }
+            SDL_stack_free(argv);
+
+        } else {
+            __android_log_print(ANDROID_LOG_ERROR, "SDL", "nativeRunMain(): Couldn't find function %s in library %s", function_name, library_file);
+        }
+        (*env)->ReleaseStringUTFChars(env, function, function_name);
+
+        dlclose(library_handle);
+
+    } else {
+        __android_log_print(ANDROID_LOG_ERROR, "SDL", "nativeRunMain(): Couldn't load library %s", library_file);
+    }
+    (*env)->ReleaseStringUTFChars(env, library, library_file);
+
+    /* Do not issue an exit or the whole application will terminate instead of just the SDL thread */
+    /* exit(status); */
+
+    return status;
 }
 
 /* Drop file */
@@ -548,6 +635,7 @@ JNIEXPORT void JNICALL SDL_JAVA_INTERFACE(nativePause)(
                                     JNIEnv* env, jclass cls)
 {
     __android_log_print(ANDROID_LOG_VERBOSE, "SDL", "nativePause()");
+
     if (Android_Window) {
         SDL_SendWindowEvent(Android_Window, SDL_WINDOWEVENT_FOCUS_LOST, 0, 0);
         SDL_SendWindowEvent(Android_Window, SDL_WINDOWEVENT_MINIMIZED, 0, 0);

src/main/android/SDL_android_main.c

@@ -1,88 +1,7 @@
 /*
     SDL_android_main.c, placed in the public domain by Sam Lantinga  3/13/14
-*/
-
-#include "SDL_config.h"
-#include "SDL.h"
-
-#ifdef __ANDROID__
-
-/* Include the SDL main definition header */
-#include "SDL_main.h"
-
-/*******************************************************************************
-                 Functions called by JNI
-*******************************************************************************/
-#include <jni.h>
-
-/* Dummy symbol so '-u SDL_main_dummy' forces ld to link in libSDL2main.a */
-JNIEXPORT int SDL_main_dummy;
-
-/* Called before SDL_main() to initialize JNI bindings in SDL library */
-extern void SDL_Android_Init(JNIEnv* env, jclass cls);
-
-/* This prototype is needed to prevent a warning about the missing prototype for global function below */
-JNIEXPORT int JNICALL Java_org_libsdl_app_SDLActivity_nativeInit(JNIEnv* env, jclass cls, jobject array);
-
-/* Start up the SDL app */
-JNIEXPORT int JNICALL Java_org_libsdl_app_SDLActivity_nativeInit(JNIEnv* env, jclass cls, jobject array)
-{
-    int i;
-    int argc;
-    int status;
-    int len;
-    char** argv;
-
-    /* This interface could expand with ABI negotiation, callbacks, etc. */
-    SDL_Android_Init(env, cls);
 
-    SDL_SetMainReady();
-
-    /* Prepare the arguments. */
-
-    len = (*env)->GetArrayLength(env, array);
-    argv = SDL_stack_alloc(char*, 1 + len + 1);
-    argc = 0;
-    /* Use the name "app_process" so PHYSFS_platformCalcBaseDir() works.
-       https://bitbucket.org/MartinFelis/love-android-sdl2/issue/23/release-build-crash-on-start
-     */
-    argv[argc++] = SDL_strdup("app_process");
-    for (i = 0; i < len; ++i) {
-        const char* utf;
-        char* arg = NULL;
-        jstring string = (*env)->GetObjectArrayElement(env, array, i);
-        if (string) {
-            utf = (*env)->GetStringUTFChars(env, string, 0);
-            if (utf) {
-                arg = SDL_strdup(utf);
-                (*env)->ReleaseStringUTFChars(env, string, utf);
-            }
-            (*env)->DeleteLocalRef(env, string);
-        }
-        if (!arg) {
-            arg = SDL_strdup("");
-        }
-        argv[argc++] = arg;
-    }
-    argv[argc] = NULL;
-
-
-    /* Run the application. */
-
-    status = SDL_main(argc, argv);
-
-    /* Release the arguments. */
-
-    for (i = 0; i < argc; ++i) {
-        SDL_free(argv[i]);
-    }
-    SDL_stack_free(argv);
-    /* Do not issue an exit or the whole application will terminate instead of just the SDL thread */
-    /* exit(status); */
-
-    return status;
-}
-
-#endif /* __ANDROID__ */
+    As of SDL 2.0.6 this file is no longer necessary.
+*/
 
 /* vi: set ts=4 sw=4 expandtab: */