index : cgit

# The rules that compile and link cgit itself. They run with the bundled Git
# tree as the working directory so that Git's build variables and platform
# detection can be reused, which is why every path back into the project leads
# through CGIT_ROOT. The top level Makefile invokes it roughly as
#
#     make -C vendor/git -f ../../source/cgit.mk ../../build/cgit

CGIT_ROOT = ../..

# Read again here because a sub make inherits only the variables the top level
# Makefile exports, which leaves out the build options this file and Git's
# Makefile read. It comes ahead of Git's Makefile, which acts on an option such
# as NO_REGEX as soon as it reads it.
-include $(CGIT_ROOT)/cgit.conf

include Makefile

# BUILDDIR is named relative to the project root because the version recipe
# changes into the root before using it. CGIT_SRC and CGIT_BUILD lead to the
# sources and the output from vendor/git, where everything else here runs.
SRCDIR     = source
BUILDDIR   = build
CGIT_SRC   = $(CGIT_ROOT)/$(SRCDIR)
CGIT_BUILD = $(CGIT_ROOT)/$(BUILDDIR)

# And once more, since Git's Makefile and the lines above set CC, CFLAGS,
# BUILDDIR and the like over whatever was read before them.
-include $(CGIT_ROOT)/cgit.conf

# The CGIT_ values used below are exported by the top level Makefile. git
# describe names the version when it runs at the top of the cgit working tree,
# rather than in the bundled git, and CGIT_VERSION stands in for a tarball or
# a clone with no tags. The file is left alone when its line is unchanged,
# since everything that includes it would otherwise rebuild.
.PHONY: force-version
$(CGIT_BUILD)/VERSION: force-version
	@mkdir -p $(CGIT_BUILD)/
	@cd $(CGIT_ROOT) && version='$(CGIT_VERSION)' && \
	if test "$$(git rev-parse --git-dir 2>/dev/null)" = .git && \
		described=$$(git describe --abbrev=4 HEAD 2>/dev/null); then \
		version=$$described; \
	fi && \
	line="CGIT_VERSION = $$version" && \
	if test "$$(cat $(BUILDDIR)/VERSION 2>/dev/null)" != "$$line"; then \
		echo "$$line" >$(BUILDDIR)/VERSION && echo "$$line"; \
	fi
-include $(CGIT_BUILD)/VERSION

# Pinned so a compiler moving its default, as GCC 15 did to gnu23, cannot
# change what the sources mean. The GNU dialect because git's headers use GNU
# extensions. Git keeps its own choice.
CGIT_STD ?= gnu17

# CGIT_CFLAGS is tracked separately so that changing it does not force a rebuild
# of Git itself.
CGIT_CFLAGS += -std=$(CGIT_STD)
CGIT_CFLAGS += -DCGIT_CONFIG='"$(CGIT_CONFIG)"'
CGIT_CFLAGS += -DCGIT_SCRIPT_NAME='"$(CGIT_SCRIPT_NAME)"'
CGIT_CFLAGS += -DCGIT_CACHE_ROOT='"$(CACHE_ROOT)"'

# Reaches only the cgit objects, so a caller can tighten the build, the way the
# release build passes -Werror=format-security, without holding git's own
# sources to the same standard.
CGIT_CFLAGS += $(CGIT_EXTRA_CFLAGS)

PKG_CONFIG ?= pkg-config

# Why pkg-config gave no Lua, for the messages below. Recursive, so the shell
# runs only when one of them is wanted.
LUA_NO_PKG_CONFIG = $(if $(shell command -v $(PKG_CONFIG) 2>/dev/null),,$(PKG_CONFIG) is not installed)

ifdef NO_LUA
	LUA_MESSAGE := linking without specified Lua support
	CGIT_CFLAGS += -DNO_LUA
else
# Each system names Lua's package its own way: lua5.4 on Debian and Alpine,
# lua-5.4 on FreeBSD and NetBSD, lua54 on OpenBSD.
ifeq ($(LUA_PKGCONFIG),)
	LUA_PKGCONFIG := $(shell for pc in luajit lua lua5.5 lua5.4 lua5.3 lua5.2 lua5.1 \
			lua-5.5 lua-5.4 lua-5.3 lua-5.2 lua-5.1 lua55 lua54 lua53 lua52 lua51; do \
			$(PKG_CONFIG) --exists $$pc 2>/dev/null && echo $$pc && break; \
			done)
	LUA_MODE := autodetected
else
	LUA_MODE := specified
endif
ifneq ($(LUA_PKGCONFIG),)
	LUA_MESSAGE := linking with $(LUA_MODE) $(LUA_PKGCONFIG)
# Flags passed by hand stand in for pkg-config's. Without them, a package it
# cannot find leaves the build no Lua flags at all, and the compile would
# then stop at lua.h without a word of why.
ifeq ($(filter command line override,$(origin LUA_LIBS) $(origin LUA_CFLAGS)),)
ifneq ($(shell $(PKG_CONFIG) --exists $(LUA_PKGCONFIG) 2>/dev/null && echo yes),yes)
	LUA_FAULT := $(or $(LUA_NO_PKG_CONFIG),$(PKG_CONFIG) does not know $(LUA_PKGCONFIG))
	LUA_MESSAGE := $(LUA_MESSAGE), though $(LUA_FAULT)
$(warning $(LUA_FAULT), so LUA_LIBS and LUA_CFLAGS are empty. Install pkg-config and the Lua development package, or pass LUA_LIBS and LUA_CFLAGS)
endif
endif
	LUA_LIBS := $(shell $(PKG_CONFIG) --libs $(LUA_PKGCONFIG) 2>/dev/null)
	LUA_CFLAGS := $(shell $(PKG_CONFIG) --cflags $(LUA_PKGCONFIG) 2>/dev/null)
	CGIT_LIBS += $(LUA_LIBS)
	CGIT_CFLAGS += $(LUA_CFLAGS)
else
	LUA_MESSAGE := linking without Lua, since $(or $(LUA_NO_PKG_CONFIG),$(PKG_CONFIG) found no Lua package). Install pkg-config and a Lua development package, or pass LUA_PKGCONFIG, LUA_LIBS and LUA_CFLAGS
	NO_LUA := YesPlease
	CGIT_CFLAGS += -DNO_LUA
endif

endif

# The filters reach libc's write through dlsym, which lives in a library of its
# own on the systems that use GNU libc.
ifneq (,$(filter $(uname_S),Linux GNU GNU/kFreeBSD))
	CGIT_LIBS += -ldl
endif

# The cache sends a stored page straight to stdout with sendfile where it can.
# Only Linux is assumed to offer it, so everywhere else falls back to reading
# and writing the file by hand.
ifeq ($(uname_S),Linux)
	HAVE_LINUX_SENDFILE = YesPlease
endif

ifdef HAVE_LINUX_SENDFILE
	CGIT_CFLAGS += -DHAVE_LINUX_SENDFILE
endif

CGIT_OBJ_NAMES += cgit.o
CGIT_OBJ_NAMES += cache.o
CGIT_OBJ_NAMES += cmd.o
CGIT_OBJ_NAMES += config.o
CGIT_OBJ_NAMES += filter.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-blame.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-empty.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_OBJS := $(addprefix $(CGIT_BUILD)/,$(CGIT_OBJ_NAMES))

# Only cgit.c references CGIT_VERSION, so only its objects rebuild when the
# version changes.
CGIT_VERSION_OBJS := $(addprefix $(CGIT_BUILD)/,cgit.o cgit.sp)
$(CGIT_VERSION_OBJS): $(CGIT_BUILD)/VERSION
$(CGIT_VERSION_OBJS): EXTRA_CPPFLAGS = -DCGIT_VERSION='"$(CGIT_VERSION)"'

# Git builds its list of dependency files with := before this file adds the
# cgit objects, so those are missing from it and have to be picked up here.
cgit_dep_files := $(foreach f,$(CGIT_OBJS),$(dir $f).depend/$(notdir $f).d)
cgit_dep_files_present := $(wildcard $(cgit_dep_files))
ifneq ($(cgit_dep_files_present),)
include $(cgit_dep_files_present)
endif

ifeq ($(wildcard $(CGIT_BUILD)/.depend),)
missing_dep_dirs += $(CGIT_BUILD)/.depend
endif

$(CGIT_BUILD)/.depend:
	@mkdir -p $@

$(CGIT_BUILD)/CGIT-CFLAGS: FORCE
	@mkdir -p $(CGIT_BUILD)/
	@FLAGS='$(subst ','\'',$(CGIT_CFLAGS))'; \
		OLD=$$(cat $(CGIT_BUILD)/CGIT-CFLAGS 2>/dev/null); \
		if test "$$FLAGS" != "$$OLD"; then \
			echo 1>&2 "    * new cgit build flags"; \
			echo "$$FLAGS" >$(CGIT_BUILD)/CGIT-CFLAGS; \
		fi

# compdb_args and missing_compdb_dir are git's, and stay empty unless
# GENERATE_COMPILATION_DATABASE asks clang for a -MJ entry per object, which
# puts cgit's sources in the database beside git's.
$(CGIT_OBJS): $(CGIT_BUILD)/%.o: $(CGIT_SRC)/%.c GIT-CFLAGS $(CGIT_BUILD)/CGIT-CFLAGS \
		$(missing_dep_dirs) $(missing_compdb_dir)
	$(QUIET_CC)$(CC) -o $@ -c $(dep_args) $(compdb_args) $(ALL_CFLAGS) $(EXTRA_CPPFLAGS) $(CGIT_CFLAGS) $<

$(CGIT_BUILD)/cgit: $(CGIT_OBJS) GIT-LDFLAGS $(GITLIBS)
	@echo 1>&2 "    * $(LUA_MESSAGE)"
	$(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS) $(CGIT_LIBS)

CGIT_SP_OBJS := $(patsubst %.o,%.sp,$(CGIT_OBJS))

# Git's SPARSE_FLAGS name a -std of their own, so they come ahead of
# CGIT_CFLAGS for sparse to read the sources in the dialect they build in.
$(CGIT_SP_OBJS): $(CGIT_BUILD)/%.sp: $(CGIT_SRC)/%.c GIT-CFLAGS $(CGIT_BUILD)/CGIT-CFLAGS FORCE
	$(QUIET_SP)cgcc -no-compile $(ALL_CFLAGS) $(EXTRA_CPPFLAGS) $(SPARSE_FLAGS) $(CGIT_CFLAGS) $<

.PHONY: cgit-sparse
cgit-sparse: $(CGIT_SP_OBJS)