#- modmake
# this is the master makefile that controls the building of each
# libk module. it is included from each k*/makefile.
# vim: ft=make

mod = $(notdir $(PWD))
src = $(wildcard *.c) $(wildcard *.s)
bare = $(mod:k%=%)

tools    = $(filter     exe.%.c,   $(src))
nontools = $(filter-out exe.%.c,   $(src))
cobjects = $(filter     %.c,       $(nontools))
sobjects = $(filter %.${TARGET}.s, $(nontools))

obj: $(cobjects:%.c=${OUT}/$(mod).%.o) \
	 $(sobjects:%.s=${OUT}/$(mod).%.o)
tool: $(tools:exe.%.c=${OUT}/$(mod).%)

dbg:
	@echo tools = $(tools)
	@echo TARGET = ${TARGET}
	@echo cobjects = $(cobjects)
	@echo sobjects = $(sobjects)
	@echo mod = $(mod)

${OUT}/$(mod).%.o: %.c
	$(CC) -c $< -o $@

${OUT}/k/$(bare).h: $(bare).h
	cp $< $@

${OUT}/$(mod).%: exe.%.c
	$(CC) $< -o $@

#- assembly
# compiling  the assembly  code will  be  faster but  a lot  more
# complex, given the  nature of assembly and the  large number of
# platforms  targeted.  we need  to  add  build rules  for  every
# arch.OS[.bits] tuple;  since this  is a fairly  repetetive task
# that  requires ugly  make  rules,  we're just  going  to use  a
# function to generate these.

# ${OUT} = ultimate build directory
# $(mod) = module name
#      % = function name
#   $(1) = arch tuple
arch = ${OUT}/$(mod).%.$(1).o: %.$(1).s
# invoke with $(call arch,tuple). do not
# put spaces between either term though!

#-- linux
# linux uses the ELF{32,64} binary format,  and generating these
# from yasm is trivial.  linux only supports one ABI per format,
# at least with ELF, so that's all we need to do.

#${OUT}/$(mod).%.x86.lin.32.o: %.x86.lin.32.s
$(call arch,x86.lin.32)
	yasm -felf32 $< -o $@

#${OUT}/$(mod).%.x86.lin.64.o: %.x86.lin.64.s
$(call arch,x86.lin.64)
	yasm -felf64 $< -o $@

#-- freebsd
# the freebsd ABI is different, so it will require different code
# (though there might be ways to minimize that). freebsd uses the
# same binary format as Linux  (though it also supports a.out and
# COFF) but because freebsd can interpret multiple different ABIs
# the  object files  need to  be "branded"  with the  correct one
# using the tool brandelf (`brandelf -t [ABI]`)

$(call arch,x86.fbsd.32)
	yasm -felf32 $< -o $@
	brandelf -t FreeBSD $@

$(call arch,x86.fbsd.64)
	yasm -felf64 $< -o $@
	brandelf -t FreeBSD $@

