fs_config: Add fs_config_generate

fs_config_generate_$(TARGET_DEVICE) is built based off the content
of $(TARGET_ANDROID_FILESYSTEM_CONFIG_H). We also add the rules
fs_config_dirs and fs_config_file to utilize this command
for target contents:

fs_config_generate_$(TARGET_DEVICE) -D -o system/etc/fs_config_dir
fs_config_generate_$(TARGET_DEVICE) -F -o system/etc/fs_config_file

In order to use this feature, one must have the fs_config_dirs and
fs_config_files in the $(PRODUCT_PACKAGES) list defined in the
device make files in $(TARGET_DEVICE_DIR). And either an
android_filesystem_config.h file in that directory, or define a
path in TARGET_ANDROID_FILESYSTEM_CONFIG_H to point to one.

Bug: 19908228
Change-Id: Iee1543d99169f874e0915ae07962a7750ecb6342

1 files changed, 61 insertions, 0 deletions

diff --git a/tools/fs_config/Android.mk b/tools/fs_config/Android.mk
index 3e16962..34a3522 100644
--- a/tools/fs_config/Android.mk
+++ b/tools/fs_config/Android.mk
@@ -22,3 +22,64 @@ LOCAL_SHARED_LIBRARIES := libcutils libselinux
 LOCAL_CFLAGS := -Werror
 
 include $(BUILD_HOST_EXECUTABLE)
+
+# To Build the custom target binary for the host to generate the fs_config
+# override files. The executable is hard coded to include the
+# $(TARGET_ANDROID_FILESYSTEM_CONFIG_H) file if it exists.
+# Expectations:
+#    device/<vendor>/<device>/android_filesystem_config.h
+#        fills in struct fs_path_config android_device_dirs[] and
+#                 struct fs_path_config android_device_files[]
+#    device/<vendor>/<device>/device.mk
+#        PRODUCT_PACKAGES += fs_config_dirs fs_config_files
+
+# If not specified, check if default one to be found
+ANDROID_FS_CONFIG_H := android_filesystem_config.h
+
+ifneq ($(TARGET_ANDROID_FILESYSTEM_CONFIG_H),)
+ifeq ($(filter %/$(ANDROID_FS_CONFIG_H),$(TARGET_ANDROID_FILESYSTEM_CONFIG_H)),)
+$(error TARGET_ANDROID_FILESYSTEM_CONFIG_H file name must be $(ANDROID_FS_CONFIG_H), \
+ see "$(notdir $(TARGET_ANDROID_FILESYSTEM_CONFIG_H))".)
+endif
+
+my_fs_config_h := $(TARGET_ANDROID_FILESYSTEM_CONFIG_H)
+else ifneq ($(wildcard $(TARGET_DEVICE_DIR)/$(ANDROID_FS_CONFIG_H)),)
+my_fs_config_h := $(TARGET_DEVICE_DIR)/$(ANDROID_FS_CONFIG_H)
+else
+my_fs_config_h := $(LOCAL_PATH)/default/$(ANDROID_FS_CONFIG_H)
+endif
+
+include $(CLEAR_VARS)
+LOCAL_SRC_FILES := fs_config_generate.c
+LOCAL_MODULE := fs_config_generate_$(TARGET_DEVICE)
+LOCAL_SHARED_LIBRARIES := libcutils
+LOCAL_CFLAGS := -Werror -Wno-error=\#warnings
+LOCAL_C_INCLUDES := $(dir $(my_fs_config_h))
+include $(BUILD_HOST_EXECUTABLE)
+fs_config_generate_bin := $(LOCAL_INSTALLED_MODULE)
+
+# Generate the system/etc/fs_config_dirs binary file for the target
+# Add fs_config_dirs to PRODUCT_PACKAGES in the device make file to enable
+include $(CLEAR_VARS)
+
+LOCAL_MODULE := fs_config_dirs
+LOCAL_MODULE_CLASS := ETC
+include $(BUILD_SYSTEM)/base_rules.mk
+$(LOCAL_BUILT_MODULE): $(fs_config_generate_bin)
+	@mkdir -p $(dir $@)
+	$< -D -o $@
+
+# Generate the system/etc/fs_config_files binary file for the target
+# Add fs_config_files to PRODUCT_PACKAGES in the device make file to enable
+include $(CLEAR_VARS)
+
+LOCAL_MODULE := fs_config_files
+LOCAL_MODULE_CLASS := ETC
+include $(BUILD_SYSTEM)/base_rules.mk
+$(LOCAL_BUILT_MODULE): $(fs_config_generate_bin)
+	@mkdir -p $(dir $@)
+	$< -F -o $@
+
+ANDROID_FS_CONFIG_H :=
+my_fs_config_h :=
+fs_config_generate_bin :=