# Copyright Authors of Cilium
# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)

FLAGS := -I$(ROOT_DIR)/bpf/include -I$(ROOT_DIR)/bpf -D__NR_CPUS__=$(shell nproc --all) -O2 -g

CLANG_FLAGS := ${FLAGS} --target=bpf -std=gnu89 -nostdinc
# eBPF verifier enforces unaligned access checks where necessary, so don't
# let clang complain too early.
CLANG_FLAGS += -Wall -Wextra -Werror -Wshadow
CLANG_FLAGS += -Wno-address-of-packed-member
CLANG_FLAGS += -Wno-unknown-warning-option
CLANG_FLAGS += -Wno-gnu-variable-sized-type-not-at-end
CLANG_FLAGS += -Wdeclaration-after-statement
CLANG_FLAGS += -Wimplicit-int-conversion -Wenum-conversion
CLANG_FLAGS += -Wimplicit-fallthrough
# Mimics the mcpu values set by cilium-agent. See GetBPFCPU().
ifeq (,$(filter $(KERNEL),419 54))
CLANG_FLAGS += -mcpu=v3
else
CLANG_FLAGS += -mcpu=v2
endif

LIB := $(shell find $(ROOT_DIR)/bpf -name '*.h')
BPF_C := $(patsubst %.o,%.c,$(BPF))
BPF_ASM := $(patsubst %.o,%.s,$(BPF))

CLANG      ?= clang
HOST_CC    ?= gcc
HOST_STRIP ?= strip

ifeq ($(CROSS_ARCH),arm64)
  HOST_CC = aarch64-linux-gnu-gcc
  HOST_STRIP = aarch64-linux-gnu-strip
else ifeq ($(CROSS_ARCH),amd64)
  HOST_CC = x86_64-linux-gnu-gcc
  HOST_STRIP = x86_64-linux-gnu-strip
endif

# Define all at the top here so that Makefiles which include this one will hit
# the 'all' target first (which we expect to be overridden by the includer).
all:

force:

%.ll: %.c $(LIB)
	@$(ECHO_CC)
	$(QUIET) ${CLANG} ${CLANG_FLAGS} -emit-llvm -c $< -o $@

%.o: %.c $(LIB)
	@$(ECHO_CC)
	$(QUIET) ${CLANG} ${CLANG_FLAGS} -c $< -o $@

#
# TODO: revert addition of ignore MACRO_ARG_REUSE below once cilium-checkpatch
# image is updated to ignore it.
#
CHECKPATCH_IMAGE := quay.io/cilium/cilium-checkpatch:a8f73eced11c29d8c5003ba75071fb9ff91251e4@sha256:9fba31c924b0e675ee45dada3788ded045cd63c979fae3cddcb08636ed2e00da
ifneq ($(CHECKPATCH_DEBUG),)
  # Run script with "bash -x"
  CHECKPATCH_IMAGE_AND_ENTRY := \
	--entrypoint /bin/bash $(CHECKPATCH_IMAGE) -x /checkpatch/checkpatch.sh -- --ignore MACRO_ARG_REUSE
else
  # Use default entrypoint
  CHECKPATCH_IMAGE_AND_ENTRY := \
	--entrypoint /bin/bash $(CHECKPATCH_IMAGE) /checkpatch/checkpatch.sh -- --ignore MACRO_ARG_REUSE
endif
checkpatch:
	@$(ECHO_CHECK) "(checkpatch)"
	$(QUIET) $(CONTAINER_ENGINE) container run --rm \
		--workdir /workspace \
		--volume $(CURDIR)/..:/workspace \
		--user "$(shell id -u):$(shell id -g)" \
		-e GITHUB_REF=$(GITHUB_REF) -e GITHUB_REPOSITORY=$(GITHUB_REPOSITORY) \
		$(CHECKPATCH_IMAGE_AND_ENTRY) $(CHECKPATCH_ARGS)

coccicheck:
	$(QUIET) $(foreach TARGET,$(shell find $(ROOT_DIR)/contrib/coccinelle/ -name '*.cocci'), \
		spatch --no-show-diff --sp-file ${TARGET} --include-headers --very-quiet --dir . ; )

check: coccicheck checkpatch
	@$(ECHO_CHECK)/*.c
	$(QUIET) sparse -Wsparse-all ${FLAGS} $(ROOT_DIR)/$(RELATIVE_DIR)/*.c
	$(QUIET) $(CLANG) ${CLANG_FLAGS} --analyze $(ROOT_DIR)/$(RELATIVE_DIR)/*.c
	$(QUIET) $(foreach SUBDIR,$(SUBDIRS), \
		$(MAKE) $(SUBMAKEOPTS) -C $(SUBDIR) $@ &&) true

preprocess: $(LIB)
	$(QUIET) $(foreach TARGET,$(shell find $(ROOT_DIR)/$(RELATIVE_DIR)/ -name 'bpf_*.c'), \
		echo "  GEN   $(patsubst %.c,%.i,${TARGET})"; \
		${CLANG} $(FLAGS) -E --target=bpf -c ${TARGET} -o $(patsubst %.c,%.i,${TARGET}); )
	$(QUIET) $(foreach SUBDIR,$(SUBDIRS), \
		$(MAKE) $(SUBMAKEOPTS) -C $(SUBDIR) $@ &&) true

assembly: $(BPF_C) $(LIB) $(BPF_ASM)
	$(QUIET) $(foreach SUBDIR,$(SUBDIRS), \
		$(MAKE) $(SUBMAKEOPTS) -C $(SUBDIR) $@ &&) true

.PHONY: all force checkpatch coccicheck check preprocess assembly