PREFIX = /usr/local
BINDIR = bin
MANDIR = share/man
MAN1 = man1

PKG_CONFIG = pkg-config
INSTALL = install

CFLAGS = -O2 -pipe
override CFLAGS += -std=gnu23 -Wall -Wextra
override CPPFLAGS += -MMD -D_GNU_SOURCE -D_DEFAULT_SOURCE -D_OPENBSD_SOURCE
LDFLAGS = -Wl,-O1 -Wl,--as-needed

# Platform-dependent checks
PLATFORM = $(shell uname)
ifeq ($(PLATFORM), Linux)
override CPPFLAGS += $(shell $(PKG_CONFIG) --cflags libbsd-overlay)
override LDLIBS += $(shell $(PKG_CONFIG) --libs libbsd-overlay)
endif
ifeq ($(PLATFORM), OpenBSD)
MANDIR = man
override CPPFLAGS += -DHAVE_PLEDGE
endif
ifeq ($(PLATFORM), NetBSD)
MANDIR = man
endif
ifeq ($(PLATFORM), SunOS)
# OpenIndiana ld doesn't recognize GNU ld flags
override LDFLAGS =
endif

PROG = can
OBJS = can.o user.o group.o action.o
DEPS = $(patsubst %.o, %.d, $(OBJS))

.PHONY: all
all: $(PROG)

$(PROG): $(OBJS)

-include $(DEPS)

.PHONY: clean
clean:
	rm -f $(PROG) $(OBJS) $(DEPS)

.PHONY: install
install:
	$(INSTALL) -Dm755 $(PROG) $(DESTDIR)$(PREFIX)/$(BINDIR)/$(PROG)
	$(INSTALL) -Dm644 $(PROG).1 $(DESTDIR)$(PREFIX)/$(MANDIR)/$(MAN1)/$(PROG).1