cgitsb/cgit.mk
John Keeping 5f323c1ff4 Makefile: re-use Git's Makefile where possible
Git does quite a lot of platform-specific detection in its Makefile,
which can result in it defining preprocessor variables that are used in
its header files.  If CGit does not define the same variables it can
result in different sizes of some structures in different places in the
same application.

For example, on Solaris Git uses it's "compat" regex library which has a
different sized regex_t structure than that available in the platform
regex.h.  This has a knock-on effect on the size of "struct rev_info"
and leads to hard to diagnose runtime issues.

In order to avoid all of this, introduce a "cgit.mk" file that includes
Git's Makefile and make all of the existing logic apply to CGit's
objects as well.  This is slightly complicated because Git's Makefile
must run in Git's directory, so all references to CGit files need to be
prefixed with "../".

In addition, OBJECTS is a simply expanded variable in Git's Makefile so
we cannot just add our objects to it.  Instead we must copy the two
applicable rules into "cgit.mk".  This has the advantage that we can
split CGit-specific CFLAGS from Git's CFLAGS and hence avoid rebuilding
all of Git whenever a CGit-specific value changes.

Signed-off-by: John Keeping <john@keeping.me.uk>
Acked-by: Jamie Couture <jamie.couture@gmail.com>
2013-03-20 21:08:32 +01:00

75 lines
2.3 KiB
Makefile

# This Makefile is run in the "git" directory in order to re-use Git's
# build variables and operating system detection. Hence all files in
# CGit's directory must be prefixed with "../".
include Makefile
CGIT_PREFIX = ../
# The CGIT_* variables are inherited when this file is called from the
# main Makefile - they are defined there.
$(CGIT_PREFIX)VERSION: force-version
@cd $(CGIT_PREFIX) && ./gen-version.sh "$(CGIT_VERSION)"
-include $(CGIT_PREFIX)VERSION
.PHONY: force-version
# CGIT_CFLAGS is a separate variable so that we can track it separately
# and avoid rebuilding all of Git when these variables change.
CGIT_CFLAGS += -DCGIT_VERSION='"$(CGIT_VERSION)"'
CGIT_CFLAGS += -DCGIT_CONFIG='"$(CGIT_CONFIG)"'
CGIT_CFLAGS += -DCGIT_SCRIPT_NAME='"$(CGIT_SCRIPT_NAME)"'
CGIT_CFLAGS += -DCGIT_CACHE_ROOT='"$(CACHE_ROOT)"'
ifdef NO_C99_FORMAT
CFLAGS += -DNO_C99_FORMAT
endif
CGIT_OBJ_NAMES += cgit.o
CGIT_OBJ_NAMES += cache.o
CGIT_OBJ_NAMES += cmd.o
CGIT_OBJ_NAMES += configfile.o
CGIT_OBJ_NAMES += html.o
CGIT_OBJ_NAMES += parsing.o
CGIT_OBJ_NAMES += scan-tree.o
CGIT_OBJ_NAMES += shared.o
CGIT_OBJ_NAMES += ui-atom.o
CGIT_OBJ_NAMES += ui-blob.o
CGIT_OBJ_NAMES += ui-clone.o
CGIT_OBJ_NAMES += ui-commit.o
CGIT_OBJ_NAMES += ui-diff.o
CGIT_OBJ_NAMES += ui-log.o
CGIT_OBJ_NAMES += ui-patch.o
CGIT_OBJ_NAMES += ui-plain.o
CGIT_OBJ_NAMES += ui-refs.o
CGIT_OBJ_NAMES += ui-repolist.o
CGIT_OBJ_NAMES += ui-shared.o
CGIT_OBJ_NAMES += ui-snapshot.o
CGIT_OBJ_NAMES += ui-ssdiff.o
CGIT_OBJ_NAMES += ui-stats.o
CGIT_OBJ_NAMES += ui-summary.o
CGIT_OBJ_NAMES += ui-tag.o
CGIT_OBJ_NAMES += ui-tree.o
CGIT_OBJ_NAMES += vector.o
CGIT_OBJS := $(addprefix $(CGIT_PREFIX),$(CGIT_OBJ_NAMES))
ifeq ($(wildcard $(CGIT_PREFIX).depend),)
missing_dep_dirs += $(CGIT_PREFIX).depend
endif
$(CGIT_PREFIX).depend:
@mkdir -p $@
$(CGIT_PREFIX)CGIT-CFLAGS: FORCE
@FLAGS='$(subst ','\'',$(CGIT_CFLAGS))'; \
if test x"$$FLAGS" != x"`cat ../CGIT-CFLAGS 2>/dev/null`" ; then \
echo 1>&2 " * new CGit build flags"; \
echo "$$FLAGS" >$(CGIT_PREFIX)CGIT-CFLAGS; \
fi
$(CGIT_OBJS): %.o: %.c GIT-CFLAGS $(CGIT_PREFIX)CGIT-CFLAGS $(missing_dep_dirs)
$(QUIET_CC)$(CC) -o $*.o -c $(dep_args) $(ALL_CFLAGS) $(EXTRA_CPPFLAGS) $(CGIT_CFLAGS) $<
$(CGIT_PREFIX)cgit: $(CGIT_OBJS) GIT-LDFLAGS $(GITLIBS)
$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS)