DESTDIR ?=
PREFIX ?= /usr/local
EXEC_PREFIX ?= $(PREFIX)
BINDIR ?= $(EXEC_PREFIX)/bin
LIBEXECDIR ?= $(EXEC_PREFIX)/libexec
DATAROOTDIR ?= $(PREFIX)/share
MANDIR ?= $(DATAROOTDIR)/man

CFLAGS += -Os -g -Wall -Wextra -pedantic
CPPFLAGS +=
LDFLAGS +=

SED ?= sed

BINS := ethermess
LIBEXECS := ethermess-backend
TOOLS := ethertype-dump arp-request
MAN1S := ethermess.1
MAN7S := ethermess.7

.SUFFIXES:
.SUFFIXES: .c .o

.PHONY: default all install uninstall clean distclean

default: $(BINS) $(LIBEXECS)

all: $(BINS) $(LIBEXECS) $(TOOLS)

ethertype-dump: ethertype-dump.o
	$(CC) -o $@ $< $(LDFLAGS)

arp-request: arp-request.o
	$(CC) -o $@ $< $(LDFLAGS)

ethermess: ethermess.py
	# I'm not sure you can make this work 100% with traditional make
	$(SED) "2s/__LIBEXECDIR__/'`printf "%s" "$(LIBEXECDIR)" | sed "s,\\\\\\\\,\\\\\\\\\\\\\\\\,g;s,/,\\\\\\\\/,g;s,"'"'",\\\\\\\\"'"'",g"`'/" < $< > $@
	chmod +x $@

ethermess-backend: ethermess-backend.o
	$(CC) -o $@ $< $(LDFLAGS)

.c.o:
	$(CC) -c $(CFLAGS) $(CPPFLAGS) -o $@ $<

install: $(BINS) $(LIBEXECS) $(MAN1S) $(MAN7S)
	install -D -m 755 -t '$(DESTDIR)$(BINDIR)' $(BINS)
	install -D -m 755 -t '$(DESTDIR)$(LIBEXECDIR)' $(LIBEXECS)
	install -D -m 644 -t '$(DESTDIR)$(MANDIR)/man1' $(MAN1S)
	install -D -m 644 -t '$(DESTDIR)$(MANDIR)/man7' $(MAN7S)
	@echo
	@echo '--------------------------------------------------------------------------------'
	@echo 'To finish the installation, set the CAP_NET_RAW on $(LIBEXECDIR)/ethermess-backend with'
	@echo
	@echo '    # setcap CAP_NET_RAW=ep $(LIBEXECDIR)/ethermess-backend'
	@echo
	@echo 'ethermess-backend needs to be able to create a raw ethernet packet socket, which'
	@echo 'is a privileged operation. CAP_NET_RAW allows it to do so without needing to run'
	@echo 'with root privileges.'
	@echo '--------------------------------------------------------------------------------'

uninstall:
	cd $(DESTDIR)$(BINDIR) && rm $(BINS)
	cd $(DESTDIR)$(LIBEXECDIR) && rm $(LIBEXECS)
	cd $(DESTDIR)$(MANDIR)/man1 && rm $(MAN1S)
	cd $(DESTDIR)$(MANDIR)/man7 && rm $(MAN7S)

clean:
	rm -f $(BINS) $(LIBEXECS) $(TOOLS) *.o

distclean: clean