add wait_for_keymaster

Bug: 79228237
Test: boots with patch
Change-Id: I581bcd4c4dd92c5b7be70eb351ecba20225e1eee
diff --git a/wait_for_keymaster.cpp b/wait_for_keymaster.cpp
new file mode 100644
index 0000000..bf26518
--- /dev/null
+++ b/wait_for_keymaster.cpp
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <android-base/logging.h>
+
+#include "Keymaster.h"
+
+int main(int argc, char** argv) {
+    setenv("ANDROID_LOG_TAGS", "*:v", 1);
+    if (getppid() == 1) {
+        // If init is calling us then it's during boot and we should log to kmsg
+        android::base::InitLogging(argv, &android::base::KernelLogger);
+    } else {
+        android::base::InitLogging(argv, &android::base::StderrLogger);
+    }
+    LOG(INFO) << "Waiting for Keymaster device";
+    android::vold::Keymaster keymaster;
+    LOG(INFO) << "Keymaster device ready";
+    return 0;
+}