# Use the default kernel version if the Makefile doesn't override it
LINUX_RELEASE?=1

ifdef CONFIG_TESTING_KERNEL
  KERNEL_PATCHVER:=$(KERNEL_TESTING_PATCHVER)
endif

LINUX_VERSION-4.9 = .253
LINUX_VERSION-4.14 = .217
LINUX_VERSION-4.19 = .171

LINUX_KERNEL_HASH-4.9.253 = 9a5b51a8350201bd38e3ff13909323a6571b4572a7b3caed76e462b07619bc18
LINUX_KERNEL_HASH-4.14.217 = 62a36a25431016d98d0f1cff98be432086c51f86fd79042bd10a867b3a924d11
LINUX_KERNEL_HASH-4.19.171 = f4e352fe0eb986e5b532b99d9b0725a67046cbb3e5f53fcd5b098cbaeb2ac60a

remove_uri_prefix=$(subst git://,,$(subst http://,,$(subst https://,,$(1))))
sanitize_uri=$(call qstrip,$(subst @,_,$(subst :,_,$(subst .,_,$(subst -,_,$(subst /,_,$(1)))))))

ifneq ($(call qstrip,$(CONFIG_KERNEL_GIT_CLONE_URI)),)
  LINUX_VERSION:=$(call sanitize_uri,$(call remove_uri_prefix,$(CONFIG_KERNEL_GIT_CLONE_URI)))
  ifeq ($(call qstrip,$(CONFIG_KERNEL_GIT_REF)),)
    CONFIG_KERNEL_GIT_REF:=HEAD
  endif
  LINUX_VERSION:=$(LINUX_VERSION)-$(call sanitize_uri,$(CONFIG_KERNEL_GIT_REF))
else
ifdef KERNEL_PATCHVER
  LINUX_VERSION:=$(KERNEL_PATCHVER)$(strip $(LINUX_VERSION-$(KERNEL_PATCHVER)))
endif
ifdef KERNEL_TESTING_PATCHVER
  LINUX_TESTING_VERSION:=$(KERNEL_TESTING_PATCHVER)$(strip $(LINUX_VERSION-$(KERNEL_TESTING_PATCHVER)))
endif
endif

split_version=$(subst ., ,$(1))
merge_version=$(subst $(space),.,$(1))
KERNEL_BASE=$(firstword $(subst -, ,$(LINUX_VERSION)))
KERNEL=$(call merge_version,$(wordlist 1,2,$(call split_version,$(KERNEL_BASE))))
KERNEL_PATCHVER ?= $(KERNEL)

# disable the md5sum check for unknown kernel versions
LINUX_KERNEL_HASH:=$(LINUX_KERNEL_HASH-$(strip $(LINUX_VERSION)))
LINUX_KERNEL_HASH?=x