android/jni: use a libvlcjni function to attach/detach java thread

Fix ART warning about java thread attached without a name.

(cherry picked from commit d26fefcfa700d3a9c1b2c26f30a1667e72ac381b)
Signed-off-by: Edward Wang <edward.c.wang@compdigitec.com>
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

modules/codec/omxil/android_mediacodec.c

@@ -46,7 +46,10 @@
 #define INFO_OUTPUT_FORMAT_CHANGED  -2
 #define INFO_TRY_AGAIN_LATER        -1
 
-extern JavaVM *myVm;
+#define THREAD_NAME "android_mediacodec"
+
+extern int jni_attach_thread(JNIEnv **env, const char *thread_name);
+extern void jni_detach_thread();
 /* JNI functions to get/set an Android Surface object. */
 extern jobject jni_LockAndGetAndroidJavaSurface();
 extern void jni_UnlockAndroidSurface();
@@ -327,7 +330,7 @@ static int OpenDecoder(vlc_object_t *p_this)
     p_dec->b_need_packetized = true;
 
     JNIEnv* env = NULL;
-    (*myVm)->AttachCurrentThread(myVm, &env, NULL);
+    jni_attach_thread(&env, THREAD_NAME);
 
     for (int i = 0; classes[i].name; i++) {
         *(jclass*)((uint8_t*)p_sys + classes[i].offset) =
@@ -539,7 +542,7 @@ static int OpenDecoder(vlc_object_t *p_this)
         goto error;
     (*env)->DeleteLocalRef(env, format);
 
-    (*myVm)->DetachCurrentThread(myVm);
+    jni_detach_thread();
 
     const int timestamp_fifo_size = 32;
     p_sys->timestamp_fifo = timestamp_FifoNew(timestamp_fifo_size);
@@ -549,7 +552,7 @@ static int OpenDecoder(vlc_object_t *p_this)
     return VLC_SUCCESS;
 
  error:
-    (*myVm)->DetachCurrentThread(myVm);
+    jni_detach_thread();
     CloseDecoder(p_this);
     return VLC_EGENERIC;
 }
@@ -567,7 +570,7 @@ static void CloseDecoder(vlc_object_t *p_this)
      * to prevent the vout from using destroyed output buffers. */
     if (p_sys->direct_rendering)
         InvalidateAllPictures(p_dec);
-    (*myVm)->AttachCurrentThread(myVm, &env, NULL);
+    jni_attach_thread(&env, THREAD_NAME);
     if (p_sys->input_buffers)
         (*env)->DeleteGlobalRef(env, p_sys->input_buffers);
     if (p_sys->output_buffers)
@@ -593,7 +596,7 @@ static void CloseDecoder(vlc_object_t *p_this)
     }
     if (p_sys->buffer_info)
         (*env)->DeleteGlobalRef(env, p_sys->buffer_info);
-    (*myVm)->DetachCurrentThread(myVm);
+    jni_detach_thread();
 
     free(p_sys->name);
     ArchitectureSpecificCopyHooksDestroy(p_sys->pixel_format, &p_sys->architecture_specific_data);
@@ -627,14 +630,14 @@ static void DisplayBuffer(picture_sys_t* p_picsys, bool b_render)
 
     /* Release the MediaCodec buffer. */
     JNIEnv *env = NULL;
-    (*myVm)->AttachCurrentThread(myVm, &env, NULL);
+    jni_attach_thread(&env, THREAD_NAME);
     (*env)->CallVoidMethod(env, p_sys->codec, p_sys->release_output_buffer, i_index, b_render);
     if ((*env)->ExceptionOccurred(env)) {
         msg_Err(p_dec, "Exception in MediaCodec.releaseOutputBuffer (DisplayBuffer)");
         (*env)->ExceptionClear(env);
     }
 
-    (*myVm)->DetachCurrentThread(myVm);
+    jni_detach_thread();
     p_picsys->b_valid = false;
 
     vlc_mutex_unlock(get_android_opaque_mutex());
@@ -896,7 +899,7 @@ static picture_t *DecodeVideo(decoder_t *p_dec, block_t **pp_block)
         return NULL;
     }
 
-    (*myVm)->AttachCurrentThread(myVm, &env, NULL);
+    jni_attach_thread(&env, THREAD_NAME);
 
     if (p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED)) {
         block_Release(p_block);
@@ -916,7 +919,7 @@ static picture_t *DecodeVideo(decoder_t *p_dec, block_t **pp_block)
             }
         }
         p_sys->decoded = false;
-        (*myVm)->DetachCurrentThread(myVm);
+        jni_detach_thread();
         return NULL;
     }
 
@@ -950,7 +953,7 @@ static picture_t *DecodeVideo(decoder_t *p_dec, block_t **pp_block)
                  * without assigning NULL to *pp_block. The next call
                  * to DecodeVideo will try to send the input packet again.
                  */
-                (*myVm)->DetachCurrentThread(myVm);
+                jni_detach_thread();
                 return p_pic;
             }
             timeout = 30 * 1000;
@@ -976,7 +979,7 @@ static picture_t *DecodeVideo(decoder_t *p_dec, block_t **pp_block)
                     block_Release(p_block);
                     *pp_block = NULL;
                 }
-                (*myVm)->DetachCurrentThread(myVm);
+                jni_detach_thread();
                 return invalid_picture;
             }
             continue;
@@ -1014,7 +1017,7 @@ static picture_t *DecodeVideo(decoder_t *p_dec, block_t **pp_block)
     }
     if (!p_pic)
         GetOutput(p_dec, env, &p_pic, 0);
-    (*myVm)->DetachCurrentThread(myVm);
+    jni_detach_thread();
 
     block_Release(p_block);
     *pp_block = NULL;

modules/video_output/android/nativewindow.c

@@ -37,7 +37,9 @@
 
 #include "utils.h"
 
-extern JavaVM *myVm;
+#define THREAD_NAME "ANativeWindow"
+extern int jni_attach_thread(JNIEnv **env, const char *thread_name);
+extern void jni_detach_thread();
 extern jobject jni_LockAndGetAndroidJavaSurface();
 extern void jni_UnlockAndroidSurface();
 extern void  jni_SetAndroidSurfaceSize(int width, int height, int visible_width, int visible_height, int sar_num, int sar_den);
@@ -89,9 +91,9 @@ static int Open(vout_window_t *wnd, const vout_window_cfg_t *cfg)
         goto error;
 
     JNIEnv *p_env;
-    (*myVm)->AttachCurrentThread(myVm, &p_env, NULL);
+    jni_attach_thread(&p_env, THREAD_NAME);
     p_sys->window = p_sys->native_window.winFromSurface(p_env, javaSurface); // ANativeWindow_fromSurface call.
-    (*myVm)->DetachCurrentThread(myVm);
+    jni_detach_thread();
 
     jni_UnlockAndroidSurface();
 

modules/video_output/android/opaque.c

@@ -50,7 +50,9 @@ vlc_module_begin()
     set_callbacks(Open, Close)
 vlc_module_end()
 
-extern JavaVM *myVm;
+#define THREAD_NAME "vout_mediacodec"
+extern int jni_attach_thread(JNIEnv **env, const char *thread_name);
+extern void jni_detach_thread();
 extern jobject jni_LockAndGetSubtitlesSurface();
 extern void  jni_UnlockAndroidSurface();
 
@@ -124,9 +126,9 @@ static void DisplaySubpicture(vout_display_t *vd, subpicture_t *subpicture)
     if (!sys->window)
     {
         JNIEnv *p_env;
-        (*myVm)->AttachCurrentThread(myVm, &p_env, NULL);
+        jni_attach_thread(&p_env, THREAD_NAME);
         sys->window = sys->native_window.winFromSurface(p_env, jsurf);
-        (*myVm)->DetachCurrentThread(myVm);
+        jni_detach_thread();
     }
 
     ANativeWindow_Buffer buf = { 0 };

modules/video_output/android/surface.c

@@ -73,7 +73,9 @@ vlc_module_end()
  * JNI prototypes
  *****************************************************************************/
 
-extern JavaVM *myVm;
+#define THREAD_NAME "AndroidSurface"
+extern int jni_attach_thread(JNIEnv **env, const char *thread_name);
+extern void jni_detach_thread();
 extern void *jni_LockAndGetAndroidSurface();
 extern jobject jni_LockAndGetAndroidJavaSurface();
 extern void  jni_UnlockAndroidSurface();
@@ -370,9 +372,9 @@ static int  AndroidLockSurface(picture_t *picture)
         sys->jsurf = jsurf;
         if (!sys->window) {
             JNIEnv *p_env;
-            (*myVm)->AttachCurrentThread(myVm, &p_env, NULL);
+            jni_attach_thread(&p_env, THREAD_NAME);
             sys->window = sys->native_window.winFromSurface(p_env, jsurf);
-            (*myVm)->DetachCurrentThread(myVm);
+            jni_detach_thread();
         }
         // Using sys->window instead of the native surface object
         // as parameter to the unlock function