# SPDX-License-Identifier: GPL-2.0

  #
  # kbuild file for usr/ - including initramfs image
  #

  # cmd_bzip2, cmd_lzma, cmd_lzo, cmd_lz4 from scripts/Makefile.lib appends the
  # size at the end of the compressed file, which unfortunately does not work
  # with unpack_to_rootfs(). Make size_append no-op.
  override size_append := :

  compress-y					:= shipped

  compress-$(CONFIG_INITRAMFS_COMPRESSION_GZIP)	:= gzip
  compress-$(CONFIG_INITRAMFS_COMPRESSION_BZIP2)	:= bzip2
  compress-$(CONFIG_INITRAMFS_COMPRESSION_LZMA)	:= lzma
  compress-$(CONFIG_INITRAMFS_COMPRESSION_XZ)	:= xzmisc
  compress-$(CONFIG_INITRAMFS_COMPRESSION_LZO)	:= lzo
  compress-$(CONFIG_INITRAMFS_COMPRESSION_LZ4)	:= lz4

  compress-$(CONFIG_INITRAMFS_COMPRESSION_ZSTD)	:= zstd

  obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data.o

  $(obj)/initramfs_data.o: $(obj)/initramfs_inc_data

  ramfs-input := $(strip $(shell echo $(CONFIG_INITRAMFS_SOURCE)))
  cpio-data :=
  
  # If CONFIG_INITRAMFS_SOURCE is empty, generate a small initramfs with the
  # default contents.
  ifeq ($(ramfs-input),)
  ramfs-input := $(srctree)/$(src)/default_cpio_list
  endif
  
  ifeq ($(words $(ramfs-input)),1)
  
  # If CONFIG_INITRAMFS_SOURCE specifies a single file, and it is suffixed with
  # .cpio, use it directly as an initramfs.
  ifneq ($(filter %.cpio,$(ramfs-input)),)
  cpio-data := $(ramfs-input)
  endif
  
  # If CONFIG_INITRAMFS_SOURCE specifies a single file, and it is suffixed with
  # .cpio.*, use it directly as an initramfs, and avoid double compression.
  ifeq ($(words $(subst .cpio.,$(space),$(ramfs-input))),2)
  cpio-data := $(ramfs-input)
  compress-y := shipped
  endif
  
  endif
  
  # For other cases, generate the initramfs cpio archive based on the contents
  # specified by CONFIG_INITRAMFS_SOURCE.
  ifeq ($(cpio-data),)
  
  cpio-data := $(obj)/initramfs_data.cpio

  hostprogs := gen_init_cpio

  # .initramfs_data.cpio.d is used to identify all files included

  # in initramfs and to detect if any files are added/removed.
  # Removed files are identified by directory timestamp being updated
  # The dependency list is generated by gen_initramfs.sh -l

  -include $(obj)/.initramfs_data.cpio.d

  # do not try to update files included in initramfs
  $(deps_initramfs): ;

  quiet_cmd_initfs = GEN     $@
        cmd_initfs = \
  	$(CONFIG_SHELL) $< -o $@ -l $(obj)/.initramfs_data.cpio.d \
  	$(if $(CONFIG_INITRAMFS_ROOT_UID), -u $(CONFIG_INITRAMFS_ROOT_UID)) \
  	$(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID)) \
  	$(ramfs-input)

  # We rebuild initramfs_data.cpio if:

  # 1) Any included file is newer than initramfs_data.cpio

  # 2) There are changes in which files are included (added or deleted)

  # 3) If gen_init_cpio are newer than initramfs_data.cpio

  # 4) Arguments to gen_initramfs.sh changes

  $(obj)/initramfs_data.cpio: $(src)/gen_initramfs.sh $(obj)/gen_init_cpio $(deps_initramfs) FORCE

  	$(call if_changed,initfs)

  endif
  
  $(obj)/initramfs_inc_data: $(cpio-data) FORCE
  	$(call if_changed,$(compress-y))
  
  targets += initramfs_data.cpio initramfs_inc_data

  subdir-$(CONFIG_UAPI_HEADER_TEST) += include