1# SPDX-License-Identifier: BSD-2-Clause
2#
3# $Id: dirdeps-cache-update.mk,v 1.23 2024/02/17 17:26:57 sjg Exp $
4#
5#	@(#) Copyright (c) 2020, Simon J. Gerraty
6#
7#	This file is provided in the hope that it will
8#	be of use.  There is absolutely NO WARRANTY.
9#	Permission to copy, redistribute or otherwise
10#	use this file is hereby granted provided that
11#	the above copyright notice and this notice are
12#	left intact.
13#
14#	Please send copies of changes and bug-fixes to:
15#	sjg@crufty.net
16#
17
18##
19#
20# This makefile deals with the updating of STATIC_DIRDEPS_CACHE.
21# Some targets are so huge that computing dirdeps takes a significant
22# amount of time.  For such targets a STATIC_DIRDEPS_CACHE can make
23# sense.
24#
25# If the target is represented by targets/pseudo/production
26# it's normal DIRDEPS would be in
27# targets/pseudo/production/Makefile.depend
28# and STATIC_DIRDEPS_CACHE would be
29# targets/pseudo/production/Makefile.dirdeps.cache
30# which is simply initialized by copying dirdeps.cache.production
31# from $OBJTOP
32#
33# When dirdeps-targets.mk is initializing DIRDEPS it will look for
34# Makefile.dirdeps.cache and unless told not to
35# (MK_STATIC_DIRDEPS_CACHE=no) will use it as DIRDEPS_CACHE.
36#
37# If MK_STATIC_DIRDEPS_CACHE_UPDATE is "yes", then this makefile
38# comes into play.
39#
40# We usually get included from local.dirdeps.mk
41# as well as Makefile.depend of RELDIR with a static Makefile.dirdeps.cache
42#
43# If we see that STATIC_DIRDEPS_CACHE is in use, we need to hook a
44# cache-update target into the build to regenerate dirdeps.cache
45# in parallel with the rest of the build.
46# If MK_STATIC_DIRDEPS_CACHE_UPDATE_IMMEDIATE is "yes" we update
47# STATIC_DIRDEPS_CACHE as soon as the update is ready,
48# otherwise it will be done at the end of the build.
49#
50# If STATIC_DIRDEPS_CACHE is not in use, but a DIRDEPS_CACHE is,
51# then we need do nothing except export STATIC_DIRDEPS_CACHE and
52# DYNAMIC_DIRDEPS_CACHE for use when we are include during the visit
53# to the ultimate target (targets/pseudo/production).
54#
55# Regardless of which happens, when included at .MAKE.LEVEL > 0
56# for a target other than cache-update we simply copy
57# DYNAMIC_DIRDEPS_CACHE to STATIC_DIRDEPS_CACHE with some optional
58# filtering.
59#
60# If we are included for the target cache-update we take care of
61# running dirdeps.mk again to generate the DYNAMIC_DIRDEPS_CACHE.
62#
63
64.if !target(_${.PARSEFILE}_)
65_${.PARSEFILE}_: .NOTMAIN
66
67STATIC_CACHE_SED += \
68	-e '/Autogenerated/s,-.*,- edit with care!,' \
69	-e '/cache-update/d'
70
71STATIC_DIRDEPS_CACHE_UPDATE_SCRIPT ?= \
72	{ echo Saving ${DYNAMIC_DIRDEPS_CACHE} as ${STATIC_DIRDEPS_CACHE}; \
73        sed ${STATIC_CACHE_SED} ${DYNAMIC_DIRDEPS_CACHE} > ${STATIC_DIRDEPS_CACHE}; }
74.endif
75
76.if ${MK_DIRDEPS_CACHE:Uno} == "yes"
77.if ${MK_STATIC_DIRDEPS_CACHE_UPDATE:Uno} == "yes"
78.if ${_debug_reldir:U0} || ${DEBUG_DIRDEPS:U:Mcache*} != ""
79_debug_cache = 1
80.else
81_debug_cache = 0
82.endif
83
84.if ${.MAKE.LEVEL} == 0 && !make(cache-update)
85
86.if ${_debug_cache}
87.info ${MK_STATIC_DIRDEPS_CACHE_UPDATE MK_STATIC_DIRDEPS_CACHE MK_DIRDEPS_CACHE DIRDEPS_CACHE STATIC_DIRDEPS_CACHE:L:@v@$v=${$v}@}
88.endif
89
90.if ${MK_STATIC_DIRDEPS_CACHE} == "yes" && defined(STATIC_DIRDEPS_CACHE) && exists(${STATIC_DIRDEPS_CACHE})
91.if !make(dirdeps) && !target(cache_update_dirdep)
92# We are using static cache and this is the only look we will get.
93# We want to generate an updated cache while we build
94# so need to hook cache-update to dirdeps now.
95# Note: we are running as a sibling to dirdeps-cached,
96# attempting to do this in that context is problematic.
97
98# One of these should exist - to actually kick off the cache generation
99.for d in ${STATIC_DIRDEPS_CACHE:H}/cache-update ${STATIC_DIRDEPS_CACHE:H:H}/cache-update ${STATIC_DIRDEPS_CACHE:H:H:H}/cache-update
100.if exists($d)
101cache_update_dirdep ?= $d.${TARGET_SPEC}
102.endif
103.endfor
104dirdeps cache_update_dirdep: ${cache_update_dirdep}
105${cache_update_dirdep}: _DIRDEP_USE
106DYNAMIC_DIRDEPS_CACHE := ${OBJTOP}/dirdeps.cache.${STATIC_DIRDEPS_CACHE:H:T}-update
107.export DYNAMIC_DIRDEPS_CACHE STATIC_DIRDEPS_CACHE
108.endif	# make(dirdeps)
109.endif	# MK_*
110
111.endif	# .MAKE.LEVEL 0
112
113.if ${.MAKE.LEVEL} > 0 && ${.CURDIR:T} == "cache-update"
114# we are the background update shim
115
116.if ${_debug_cache}
117.info level ${.MAKE.LEVEL}: ${MK_DIRDEPS_CACHE DYNAMIC_DIRDEPS_CACHE STATIC_DIRDEPS_CACHE:L:@v@$v=${$v}@}
118.endif
119
120all: cache-build
121cache-build: .META
122	@set -x; MAKELEVEL=0 \
123	${.MAKE} -C ${SRCTOP} -f ${RELDIR}/Makefile cache-update \
124	-DWITHOUT_STATIC_DIRDEPS_CACHE_UPDATE
125
126.endif	# cache-update
127
128.elif ${.MAKE.LEVEL} == 0 && make(cache-update) && !target(cache-update)
129# we were invoked above
130# we just leverage dirdeps.mk
131BUILD_DIRDEPS_TARGETS := ${STATIC_DIRDEPS_CACHE:H:T}
132DIRDEPS := ${STATIC_DIRDEPS_CACHE:H:S,^${SRCTOP}/,,}.${TARGET_SPEC}
133DIRDEPS_CACHE := ${DYNAMIC_DIRDEPS_CACHE}
134
135.if ${DEBUG_DIRDEPS:U:Mcache*} != ""
136.info level 0: ${MK_DIRDEPS_CACHE DIRDEPS_CACHE DIRDEPS:L:@v@$v=${$v}@}
137.endif
138
139# so cache-built below can check on us
140x!= echo; echo ${.MAKE.PID} > ${DIRDEPS_CACHE}.new.pid
141
142cache-update: ${DIRDEPS_CACHE}
143	@rm -f ${DIRDEPS_CACHE}.new.pid
144.if ${MK_STATIC_DIRDEPS_CACHE_UPDATE_IMMEDIATE:Uno} == "yes"
145	${STATIC_DIRDEPS_CACHE_UPDATE_SCRIPT}
146.endif
147
148all:
149
150.include <dirdeps.mk>
151
152.endif	# MK_STATIC_DIRDEPS_CACHE_UPDATE
153.endif	# MK_DIRDEPS_CACHE
154
155.if ${.MAKE.LEVEL} > 0 && ${MK_STATIC_DIRDEPS_CACHE_UPDATE:Uno} == "yes" && \
156	${STATIC_DIRDEPS_CACHE:Uno:H} == "${SRCTOP}/${RELDIR}"
157.if !defined(DYNAMIC_DIRDEPS_CACHE)
158all:
159.else
160# This is the easy bit, time to save the cache
161
162all: cache-update
163
164# ensure the cache update is completed
165cache-built:
166	@test -s ${DYNAMIC_DIRDEPS_CACHE}.new || exit 0; \
167	pid=`cat ${DYNAMIC_DIRDEPS_CACHE}.new.pid 2> /dev/null`; \
168	test $${pid:-0} -gt 1 || exit 0; \
169	echo "Waiting for $$pid to finish ${DYNAMIC_DIRDEPS_CACHE} ..."; \
170	while 'kill' -0 $$pid; do sleep 30; done > /dev/null 2>&1
171
172cache-update: cache-built
173.if ${MK_STATIC_DIRDEPS_CACHE_UPDATE_IMMEDIATE:Uno} == "no"
174	@test ! -s ${DYNAMIC_DIRDEPS_CACHE} || \
175	${STATIC_DIRDEPS_CACHE_UPDATE_SCRIPT}
176.endif
177
178.endif
179.endif
180