Boot control HAL based on the A/B headers.

The added bootctrl.bcb module implement the legacy interface for the
bootctrl HAL based on the Boot Control Block (BCB) and the headers
already specified in the booloader_message library.

This serves as a reference implementation of the boot_control HAL.

Bug: 32707546
Test: Tested internally that a device can use this HAL to flip slots and
recovery from a /misc wipe.

Change-Id: Ic02e5aaf4de7d0a1780eac4e8705dae20d0b3e10
diff --git a/boot_control/Android.mk b/boot_control/Android.mk
new file mode 100644
index 0000000..27e3d97
--- /dev/null
+++ b/boot_control/Android.mk
@@ -0,0 +1,34 @@
+#
+# Copyright (C) 2017 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.
+#
+
+LOCAL_PATH := $(my-dir)
+
+include $(CLEAR_VARS)
+LOCAL_MODULE := bootctrl.bcb
+LOCAL_MODULE_RELATIVE_PATH := hw
+LOCAL_SRC_FILES := boot_control.cpp
+LOCAL_CFLAGS := \
+  -D_FILE_OFFSET_BITS=64 \
+  -Werror \
+  -Wall \
+  -Wextra \
+  -Wno-unused-parameter
+LOCAL_SHARED_LIBRARIES := liblog
+LOCAL_STATIC_LIBRARIES := libbootloader_message libfs_mgr libbase
+LOCAL_POST_INSTALL_CMD := \
+  $(hide) mkdir -p $(TARGET_OUT_SHARED_LIBRARIES)/hw && \
+  ln -sf bootctrl.bcb.so $(TARGET_OUT_SHARED_LIBRARIES)/hw/bootctrl.default.so
+include $(BUILD_SHARED_LIBRARY)