OBJS = \
  start.o \
  console.o \
  uart.o \
  kalloc.o \
  spinlock.o \
  string.o \
  main.o \
  vm.o \
  proc.o \
  swtch.o \
  trampoline.o \
  trap.o \
  syscall.o \
  sysproc.o \
  bio.o \
  fs.o \
  log.o \
  sleeplock.o \
  file.o \
  pipe.o \
  ramdisk.o \
  exec.o \
  sysfile.o \
  kernelvec.o \
  plic.o

# riscv64-unknown-elf- or riscv64-linux-gnu-
# perhaps in /opt/riscv/bin
#TOOLPREFIX = 

# Try to infer the correct TOOLPREFIX if not set
ifndef TOOLPREFIX
TOOLPREFIX := $(shell if riscv64-unknown-elf-objdump -i 2>&1 | grep 'elf64-big' >/dev/null 2>&1; \
	then echo 'riscv64-unknown-elf-'; \
	elif riscv64-linux-gnu-objdump -i 2>&1 | grep 'elf64-big' >/dev/null 2>&1; \
	then echo 'riscv64-linux-gnu-'; \
	else echo "***" 1>&2; \
	echo "*** Error: Couldn't find an riscv64 version of GCC/binutils." 1>&2; \
	echo "*** To turn off this error, run 'gmake TOOLPREFIX= ...'." 1>&2; \
	echo "***" 1>&2; exit 1; fi)
endif

QEMU = qemu-system-riscv64

CC = $(TOOLPREFIX)gcc
AS = $(TOOLPREFIX)gas
LD = $(TOOLPREFIX)ld
OBJCOPY = $(TOOLPREFIX)objcopy
OBJDUMP = $(TOOLPREFIX)objdump

# CFLAGS = -fno-pic -static -fno-builtin -fno-strict-aliasing -Wall -MD -ggdb -Werror -fno-omit-frame-pointer -O
CFLAGS = -Wall -Werror -O
CFLAGS += -mcmodel=medany
CFLAGS += -ffreestanding -fno-common -nostdlib -mno-relax
CFLAGS += $(shell $(CC) -fno-stack-protector -E -x c /dev/null >/dev/null 2>&1 && echo -fno-stack-protector)

# Disable PIE when possible (for Ubuntu 16.10 toolchain)
ifneq ($(shell $(CC) -dumpspecs 2>/dev/null | grep -e '[^f]no-pie'),)
CFLAGS += -fno-pie -no-pie
endif
ifneq ($(shell $(CC) -dumpspecs 2>/dev/null | grep -e '[^f]nopie'),)
CFLAGS += -fno-pie -nopie
endif

LDFLAGS = -z max-page-size=4096

kernel: $(OBJS) entry.o kernel.ld initcode
	$(LD) $(LDFLAGS) -T kernel.ld -o kernel entry.o $(OBJS) 
	$(OBJDUMP) -S kernel > kernel.asm
	$(OBJDUMP) -t kernel | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > kernel.sym

initcode: initcode.S
	$(CC) $(CFLAGS) -nostdinc -I. -c initcode.S
	$(LD) $(LDFLAGS) -N -e start -Ttext 0 -o initcode.out initcode.o
	$(OBJCOPY) -S -O binary initcode.out initcode
	$(OBJDUMP) -S initcode.o > initcode.asm

tags: $(OBJS) entryother.S _init
	etags *.S *.c

vectors.S: vectors.pl
	./vectors.pl > vectors.S

ULIB = ulib.o usys.o printf.o umalloc.o

_%: %.o $(ULIB)
	$(LD) $(LDFLAGS) -N -e main -Ttext 0 -o $@ $^
	$(OBJDUMP) -S $@ > $*.asm
	$(OBJDUMP) -t $@ | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > $*.sym

usys.S : usys.pl
	perl ./usys.pl > usys.S

_forktest: forktest.o $(ULIB)
	# forktest has less library code linked in - needs to be small
	# in order to be able to max out the proc table.
	$(LD) $(LDFLAGS) -N -e main -Ttext 0 -o _forktest forktest.o ulib.o usys.o
	$(OBJDUMP) -S _forktest > forktest.asm

mkfs: mkfs.c fs.h
	gcc -Werror -Wall -o mkfs mkfs.c

# Prevent deletion of intermediate files, e.g. cat.o, after first build, so
# that disk image changes after first build are persistent until clean.  More
# details:
# http://www.gnu.org/software/make/manual/html_node/Chained-Rules.html
.PRECIOUS: %.o

UPROGS=\
	_cat\
	_echo\
	_forktest\
	_grep\
	_init\
	_kill\
	_ln\
	_ls\
	_mkdir\
	_rm\
	_sh\
	_stressfs\
	_usertests\
	_wc\
	_zombie\

fs.img: mkfs README $(UPROGS)
	./mkfs fs.img README $(UPROGS)

-include *.d

clean: 
	rm -f *.tex *.dvi *.idx *.aux *.log *.ind *.ilg \
	*.o *.d *.asm *.sym vectors.S bootblock entryother \
	initcode initcode.out kernel fs.img kernelmemfs \
	mkfs .gdbinit \
	$(UPROGS)

# make a printout
FILES = $(shell grep -v '^\#' runoff.list)
PRINT = runoff.list runoff.spec README toc.hdr toc.ftr $(FILES)

xv6.pdf: $(PRINT)
	./runoff
	ls -l xv6.pdf

print: xv6.pdf

# try to generate a unique GDB port
GDBPORT = $(shell expr `id -u` % 5000 + 25000)
# QEMU's gdb stub command line changed in 0.11
QEMUGDB = $(shell if $(QEMU) -help | grep -q '^-gdb'; \
	then echo "-gdb tcp::$(GDBPORT)"; \
	else echo "-s -p $(GDBPORT)"; fi)
ifndef CPUS
CPUS := 1
endif
QEMUOPTS = -machine virt -kernel kernel -m 3G -smp $(CPUS) -nographic
QEMUOPTS += -initrd fs.img

qemu: kernel fs.img
	$(QEMU) $(QEMUOPTS)

.gdbinit: .gdbinit.tmpl-riscv
	sed "s/:1234/:$(GDBPORT)/" < $^ > $@

qemu-gdb: kernel .gdbinit fs.img
	@echo "*** Now run 'gdb'." 1>&2
	$(QEMU) $(QEMUOPTS) -S $(QEMUGDB)

qemu-nox-gdb: fs.img kernel .gdbinit
	@echo "*** Now run 'gdb'." 1>&2
	$(QEMU) -nographic $(QEMUOPTS) -S $(QEMUGDB)

# CUT HERE
# prepare dist for students
# after running make dist, probably want to
# rename it to rev0 or rev1 or so on and then
# check in that version.

EXTRA=\
	mkfs.c ulib.c user.h cat.c echo.c forktest.c grep.c kill.c\
	ln.c ls.c mkdir.c rm.c stressfs.c usertests.c wc.c zombie.c\
	printf.c umalloc.c\
	README dot-bochsrc *.pl toc.* runoff runoff1 runoff.list\
	.gdbinit.tmpl gdbutil\

dist:
	rm -rf dist
	mkdir dist
	for i in $(FILES); \
	do \
		grep -v PAGEBREAK $$i >dist/$$i; \
	done
	sed '/CUT HERE/,$$d' Makefile >dist/Makefile
	echo >dist/runoff.spec
	cp $(EXTRA) dist

dist-test:
	rm -rf dist
	make dist
	rm -rf dist-test
	mkdir dist-test
	cp dist/* dist-test
	cd dist-test; $(MAKE) print
	cd dist-test; $(MAKE) bochs || true
	cd dist-test; $(MAKE) qemu

# update this rule (change rev#) when it is time to
# make a new revision.
tar:
	rm -rf /tmp/xv6
	mkdir -p /tmp/xv6
	cp dist/* dist/.gdbinit.tmpl /tmp/xv6
	(cd /tmp; tar cf - xv6) | gzip >xv6-rev10.tar.gz  # the next one will be 10 (9/17)

.PHONY: dist-test dist