JNIEnv *ff_jni_attach_env(int *attached, void *log_ctx) { int ret = 0; JNIEnv *env = NULL; *attached = 0; pthread_mutex_lock(&lock); if (java_vm == NULL && (java_vm = av_jni_get_java_vm(log_ctx)) == NULL) { av_log(log_ctx, AV_LOG_INFO, "Retrieving current Java virtual machine using Android JniInvocation wrapper\n"); if (check_jni_invocation(log_ctx) == 0) { if ((java_vm = get_java_vm(NULL, log_ctx)) != NULL || (java_vm = get_java_vm("libdvm.so", log_ctx)) != NULL || (java_vm = get_java_vm("libart.so", log_ctx)) != NULL) { av_log(log_ctx, AV_LOG_INFO, "Found Java virtual machine using Android JniInvocation wrapper\n"); } } } pthread_mutex_unlock(&lock); if (!java_vm) { av_log(log_ctx, AV_LOG_ERROR, "Could not retrieve a Java virtual machine\n"); return NULL; } ret = (*java_vm)->GetEnv(java_vm, (void **)&env, JNI_VERSION_1_6); switch(ret) { case JNI_EDETACHED: if ((*java_vm)->AttachCurrentThread(java_vm, &env, NULL) != 0) { av_log(log_ctx, AV_LOG_ERROR, "Failed to attach the JNI environment to the current thread\n"); env = NULL; } else { *attached = 1; } break; case JNI_OK: break; case JNI_EVERSION: av_log(log_ctx, AV_LOG_ERROR, "The specified JNI version is not supported\n"); break; default: av_log(log_ctx, AV_LOG_ERROR, "Failed to get the JNI environment attached to this thread"); break; } return env; }