#	Makefile for i386 boot program
#	define FLOPPY and SMALL using DEFINES macro as necessary

DIR = boot2
include ../MakePaths.dir

OPTIM = -Os -Oz
CFLAGS	= $(RC_CFLAGS) $(OPTIM) $(MORECPP) -arch i386 -g -Wmost -Werror \
          -DSAIO_INTERNAL_USER \
	  -Wno-deprecated-declarations \
          $(STANDALONE_CFLAGS)
DEFINES=
CONFIG = hd
SYMDIR = $(SYMROOT)
LIBSADIR = ../libsa
LIBSAIODIR = ../libsaio
UTILDIR = ../util
INC = -I. -I.. -I$(SYMDIR) -I$(LIBSADIR) -I$(LIBSAIODIR) -I$(UTILDIR)
ifneq "" "$(wildcard /bin/mkdirs)"
  MKDIRS = /bin/mkdirs
else
  MKDIRS = /bin/mkdir -p
endif
AS = as
LD = gcc
# LIBS= -lc_static
LIBS= -L$(SYMDIR) -lsaio -lsa
LIBDEP= $(SYMDIR)/libsaio.a $(SYMDIR)/libsa.a

OTHER_FILES =

INSTALLDIR = $(DSTROOT)/usr/standalone/i386
VPATH = $(OBJROOT):$(SYMROOT)

# The ordering is important;
# sectorder.o and boot2.o must be the first two objects.
OBJS = sectorder.o boot2.o loseg_utils.o boot.o graphics.o drivers.o prompt.o options.o lzss.o mboot.o preboot.o
# button.o browser.o scrollbar.o == NOTYET	

UTILDIR = ../util
SFILES = sectorder.s boot2.s
CFILES = boot.c graphics.c drivers.c prompt.c options.c mboot.c preboot.c
HFILES = boot.h appleClut8.h appleboot.h mboot.h multiboot.h
OTHERFILES = Makefile
ALLSRC = $(FOREIGNSRC) $(FOREIGNBIN) $(SFILES) $(CFILES) \
	$(HFILES) $(OTHERFILES)
DIRS_NEEDED = $(OBJROOT) $(SYMROOT)
BOOT2ADDR = 20200
# 65024 == 64k - 512 bytes which is the most the old bootsectors can load
#MAXBOOTSIZE = 65024
# Now that __LOSEG is used we can get quite a bit larger. In fact, probably larger than
# this limit here so long as when running the stack doesn't encroach down into the BSS.
MAXBOOTSIZE = 131072

all: $(DIRS_NEEDED) boot

# -segment_order, -image_base, and -segaddr:
# Ugh...
# What we want is a binary that looks like this
# 0x20200: __LOSEG
# 0x20..0: __TEXT
# 0x....0: __DATA
#
# That is, __LOSEG must be the first segment and it mut be at exactly 0x20200
#
# Getting it at exactly 0x20200 is accomplished with -segaddr __LOSEG 0x20200
# Getting __TEXT to come after it is trickier.  Unfortunately the
# -segment_order flag is effectively superseded as soon as you manually lay
# out a section with segaddr so the next available segment (__TEXT) gets laid
# out at location 0 (the default image base for preload)
#
# Unfortunately the segalign option is completely ignored with the latest linker
# meaning that if you want the linker to find the next aligned location for a
# segment it will do so on a page (4k) boundary, not the specified boundary
#
# So you actually need the next segment (__TEXT) to come after the __LOSEG
# which means -image_base must be after the end of __LOSEG and also page aligned
# which means even though we use 0x20200 for image_base this is rounded up to
# 0x21000 and that works although wastes almost 3k.
#
# Also -seg_page_size can only increase the page size to 4k multiples, not decrease it.
#
# About the only thing I can think to do here long-term is to use ld -r to produce
# a single relocatable MH_OBJECT then get the size of each segment, round it up
# to the next paragraph boundary (the alignment we actually want) and manually lay
# out every segment according to that (i.e. output a segaddr for all segments)
# It is unfortunate that segaddr seems to be the only thing that can override
# the 4k alignment.
# Another possiblity similarly uses ld -r but then instead of laying out each
# segment actually produce a new .o with every segment combined into one with
# different section names and then make a 512-byte zero page to account for the
# first 512-byte hole and update machOconv to ignore this.
# Yet another possibility is to rewrite __LOSEG into __TEXT in the actual code
# and therefore only pay the page alignment size penalty for __DATA.
# Although for reasons I don't understand it seems __DATA does not have to be
# page aligned.
boot: machOconv $(OBJS) $(LIBDEP)
	$(LD) -static -Wl,-preload \
		-Wl,-image_base,$(BOOT2ADDR) \
		-Wl,-segment_order,__LOSEG:__TEXT:__DATA \
		-Wl,-segaddr,__LOSEG,$(BOOT2ADDR) \
		-Wl,-e,boot2 \
		-Wl,-dead_strip \
		-Wl,-no_pie \
	        -nostdlib -arch i386 -Wl,-segalign,20 \
		-o $(SYMROOT)/boot.sys $(filter %.o,$^) $(LIBS) -lcc_kext
	dsymutil -f $(SYMROOT)/boot.sys
	machOconv $(SYMROOT)/boot.sys $(SYMROOT)/boot || rm $(SYMROOT)/boot && test -f $(SYMROOT)/boot
	size $(SYMROOT)/boot.sys
	ls -l $(SYMROOT)/boot
	@( size=`ls -l $(SYMROOT)/boot | awk '{ print $$5}'` ; \
	  if expr "$$size" ">" "$(MAXBOOTSIZE)" > /dev/null ;\
	  then \
	    echo "Booter executable larger than $(MAXBOOTSIZE) bytes" ;\
	    rm $(SYMROOT)/boot ;\
	    exit 1;\
	  fi)

prompt.o: vers.h
vers.h:
	echo "#define I386BOOT_VERSION \"`vers_string -f 5.0`\"" | \
	  tr - . > $(SYMROOT)/vers.h

install_i386:: all $(INSTALLDIR)
	cp $(SYMROOT)/boot $(OTHER_FILES) $(INSTALLDIR)
	cd $(INSTALLDIR); chmod u+w boot $(OTHER_FILES)

clean::
	rm -f $(SYMROOT)/boot.sys $(SYMROOT)/boot.sys.dwarf $(SYMROOT)/boot $(SYMROOT)/vers.h

include ../MakeInc.dir

# Build sectorder.o with the -n assembler flag so it can declare sections ordered before __TEXT,__text
sectorder.o: CPPFLAGS += -Wa,-n
$(OBJROOT)/sectorder.o: CPPFLAGS += -Wa,-n

#dependencies
-include $(OBJROOT)/Makedep