Makefile

BUILD_DIR ?= .build
PROG      ?= ota-tool
#PROTOC    ?= $(shell which protoc)


include lib/libs.mk


###
# ota-tool
#

INCLUDE += src $(BUILD_DIR)/src

SRC          += $(wildcard src/*.cc) src/update_metadata.pb.cc
OBJ           = $(addprefix $(BUILD_DIR)/,$(SRC:=.o))
PROG_DEPS     = $(OBJ) $(addprefix $(BUILD_DIR)/, $(LIBS))
BUILD_CMD     = $(CXX) -flto -w -s $(OBJ) -L$(BUILD_DIR) -llzma -lcrypto $(addprefix -l:,$(LIBS))
.DEFAULT_GOAL = $(PROG)

$(PROG): $(PROG_DEPS)
	@ echo "[LD]\t$@"
	@ $(BUILD_CMD) -o $@

$(PROG)-static: $(PROG_DEPS)
	@ echo "[LD]\t$@"
	@ $(BUILD_CMD) -static -o $@

clean:
	rm -rf $(BUILD_DIR) $(PROG)


###
# Protoc generation
#

$(addprefix $(BUILD_DIR)/, $(wildcard src/*.cc)): $(BUILD_DIR)/src/update_metadata.pb.cc
$(BUILD_DIR)/%.pb.cc: %.proto $(PROTOC)
	@ echo "[PROTO]\t$<"
	@ mkdir -p $(dir $@)
	@ $(PROTOC) --cpp_out=$(BUILD_DIR) $<

# We add a phony target for protoc so that if you set PROTOC=protoc (ie
# using the host protoc in path), make doesn't try to build it as a file
# in this directory.
.PHONY: protoc

###
# General C(++)
#

INCLUDE += $(BUILD_DIR)
CFLAGS   = $(addprefix -I,$(INCLUDE)) -flto
CXXFLAGS = -std=gnu++17 $(CFLAGS)
LDFLAGS  = -Wl,--copy-dt-needed-entries

# Need to replace the LOG statement with a single ; so that a statement
# still exists. This is because some LOG calls are in an if/else block
# without brackets.
$(BUILD_DIR)/%.cc: %.cc
	@ mkdir -p $(dir $@)
	@ sed -z 's/\(\n *\)[A-Z_]*LOG[^;]*;\n/\1;\n/g' $< > $@

$(BUILD_DIR)/%.cc.o: $(BUILD_DIR)/%.cc
	@ echo "[CPP]\t$@"
	@ mkdir -p $(dir $@)
	@ $(CXX) $(CXXFLAGS) -c -o $@ $< $(LDFLAGS)

$(BUILD_DIR)/%.c.o: %.c
	@ echo "[CC]\t$@"
	@ mkdir -p $(dir $@)
	@ $(CC) $(CFLAGS) -c -o $@ $< $(LDFLAGS)