Error correction: Add a tool for en/decoding files

Add fec, a tool for generating error-correcting codes for files
and recovering them.

Bug: 21893453
Change-Id: I389c92e5cc7f825d632759b9f96045767e74120a

Author: samitolvanen

verity/Android.mk

@@ -105,3 +105,5 @@ LOCAL_STATIC_LIBRARIES := libsparse_host libz
 LOCAL_SHARED_LIBRARIES := libcrypto-host libbase
 LOCAL_CFLAGS += -Wall -Werror
 include $(BUILD_HOST_EXECUTABLE)
+
+include $(call first-makefiles-under,$(LOCAL_PATH))

verity/fec/Android.mk

@@ -0,0 +1,43 @@
+LOCAL_PATH:= $(call my-dir)
+
+ifeq ($(HOST_OS),linux)
+
+include $(CLEAR_VARS)
+LOCAL_CLANG := true
+LOCAL_SANITIZE := integer
+LOCAL_MODULE := fec
+LOCAL_SRC_FILES := main.cpp image.cpp
+LOCAL_MODULE_TAGS := optional
+LOCAL_STATIC_LIBRARIES := \
+    libsparse_host \
+    libz \
+    libcrypto_static \
+    libfec_host \
+    libfec_rs_host \
+    libext4_utils_host \
+    libsquashfs_utils_host
+LOCAL_SHARED_LIBRARIES := libbase
+LOCAL_CFLAGS += -Wall -Werror -O3
+LOCAL_C_INCLUDES += external/fec
+include $(BUILD_HOST_EXECUTABLE)
+
+endif # HOST_OS == linux
+
+include $(CLEAR_VARS)
+LOCAL_CLANG := true
+LOCAL_SANITIZE := integer
+LOCAL_MODULE := fec
+LOCAL_FORCE_STATIC_EXECUTABLE := true
+LOCAL_SRC_FILES := main.cpp image.cpp
+LOCAL_MODULE_TAGS := optional
+LOCAL_STATIC_LIBRARIES := \
+    libcrypto_static \
+    libfec \
+    libfec_rs \
+    libbase \
+    libext4_utils_static \
+    libsquashfs_utils \
+    libcutils
+LOCAL_CFLAGS += -Wall -Werror -O3 -DIMAGE_NO_SPARSE=1
+LOCAL_C_INCLUDES += external/fec
+include $(BUILD_EXECUTABLE)