.Nice.mk

# rebuild everything when the makefile is modified
.EXTRA_PREREQS += Makefile .Nice.mk

# disable builtin rules to improve speed
MAKEFLAGS += --no-builtin-rules
.SUFFIXES:

# delete target files when an error occurs
.DELETE_ON_ERROR:

# location for intermediate files (.o and .mk)
# (will be created automatically, as well as any subdirectories)
# (ex: src `subdir/file` will create `.junk/subdir/` and compile `subdir/file.c` to `.junk/subdir/file.o`)
junkbase := .junk
junkdir := $(junkbase)/$(output)
srcdir ?= .

# print status nicely (assumes ansi-compatible terminal)
empty :=
comma := ,
printlist = [$1m$(subst $(empty) $(empty),$(comma) [$1m,$(2:$3%=[$1m%))
print = echo '$(call printlist,33,$1,$2)	from: $(call printlist,32,$3,$4)'


ifdef pkgs
 # check if the required packages are installed
 $(shell pkg-config --print-errors --short-errors --exists $(pkgs))
 ifneq ($(.SHELLSTATUS),0)
  $(error MISSING PACKAGES?)
 endif
 # then get the flags
 CFLAGS += $(shell pkg-config --cflags $(pkgs))
 libflags := $(shell pkg-config --libs $(pkgs))
endif

# Link
$(output): $(srcs:%=$(junkdir)/%.o)
	@$(call print,$@,,$^,$(junkdir)/)
	@$(CC) $^ $(libflags) $(libs:%=-l%) -o $@

# Compile
# (this should be a grouped target ( &: instead of : ) but,
#  that is only supported in newer versons of make,
#  which most people don't have)
$(junkdir)/%.o $(junkdir)/%.mk : $(srcdir)/%
	@mkdir -p $(@D)
	@$(call print,$(junkdir)/$*.o,$(junkdir)/,$^,$(srcdir)/)
# I replace `-I...` with `-isystem...` here, which will mark these
# as "system headers" so they won't be added to the dependency lists.
# this is a hack, and I'm not sure how safe it is...
# (If this breaks, the next best option would be to strip
#  certain entries from the dependency file, after it is generated)
	@$(CC) $(CFLAGS:-I%=-isystem%) $(defines:%=-D%) -MMD -MP -MF$(junkdir)/$*.mk -MQ$(junkdir)/$*.mk -MQ$(<:%=$(junkdir)/%.o) -c $< -o $(junkdir)/$*.o

.PHONY: clean
clean:
	$(RM) -r $(junkbase)
	$(RM) $(output)
ifdef clean_extra # extra user defined files to be cleaned
	$(RM) $(clean_extra)
endif

ifneq ($(findstring clean,$(MAKECMDGOALS)),)
 #disable multiple jobs when clean is running, since that will break.
 .NOTPARALLEL:
else
 ifeq ($(findstring B,$(MAKEFLAGS)),)
# if `clean` is specified as a goal, or if the -B flag is passed,
# we skip including these files, because that will be redundant.
# (and it would mess with `clean`, because Make will try to
#  generate these included files if they don't exist)

# alright this is also a problem when running make uninstall etc. ugh.
  include $(srcs:%=$(junkdir)/%.mk)
 endif
endif