xref: /freebsd/share/mk/auto.obj.mk (revision a40d73475b1d716142dd32c29a16d5f9fc418f7d)
1# SPDX-License-Identifier: BSD-2-Clause
2#
3# $Id: auto.obj.mk,v 1.20 2025/05/17 15:29:55 sjg Exp $
4#
5#	@(#) Copyright (c) 2004-2025, 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
18ECHO_TRACE ?= echo
19
20.ifndef Mkdirs
21# A race condition in some versions of mkdir, means that it can bail
22# if another process made a dir that mkdir expected to.
23# We repeat the mkdir -p a number of times to try and work around this.
24# We stop looping as soon as the dir exists.
25# If we get to the end of the loop, a plain mkdir will issue an error.
26Mkdirs= Mkdirs() { \
27	for d in $$*; do \
28		for i in 1 2 3 4 5 6; do \
29			mkdir -p $$d; \
30			test -d $$d && return 0; \
31		done > /dev/null 2>&1; \
32		mkdir $$d || exit $$?; \
33	done; }
34.endif
35
36# if MKOBJDIRS is set to auto (and NOOBJ isn't defined) do some magic...
37# This will automatically create objdirs as needed.
38# Skip it if we are just doing 'clean'.
39.if ${MK_AUTO_OBJ:Uno} == "yes"
40MKOBJDIRS= auto
41.endif
42.if !defined(NOOBJ) && !defined(NO_OBJ) && ${MKOBJDIRS:Uno} == auto
43# Use __objdir here so it is easier to tweak without impacting
44# the logic.
45.if !empty(MAKEOBJDIRPREFIX)
46.if ${.CURDIR:M${MAKEOBJDIRPREFIX}/*} != ""
47# we are already in obj tree!
48__objdir?= ${.CURDIR}
49.endif
50__objdir?= ${MAKEOBJDIRPREFIX}${.CURDIR}
51.endif
52__objdir?= ${MAKEOBJDIR:Uobj}
53# relative dirs can cause trouble below
54# keep it simple and convert to absolute path now if needed
55.if ${__objdir:M/*} == ""
56# avoid ugly ${.CURDIR}/./obj etc.
57__objdir:= ${.CURDIR}/${__objdir:S,^./,,}
58.endif
59.if ${.OBJDIR:tA} != ${__objdir:tA}
60# We need to chdir, make the directory if needed
61.if !exists(${__objdir}/) && \
62	(${.TARGETS} == "" || ${.TARGETS:Nclean*:N*clean:Ndestroy*} != "")
63# This will actually make it...
64__objdir_made != echo ${__objdir}/; umask ${OBJDIR_UMASK:U002}; \
65        ${ECHO_TRACE} "[Creating objdir ${__objdir}...]" >&2; \
66        ${Mkdirs}; Mkdirs ${__objdir}
67.endif
68# This causes make to use the specified directory as .OBJDIR
69.OBJDIR: ${__objdir}
70.if ${.OBJDIR:tA} != ${__objdir:tA}
71# we did not get what we want - do we care?
72.if ${__objdir_made:Uno:M${__objdir}/*} != ""
73# we attempted to make ${__objdir} and failed
74.error could not use ${__objdir}: .OBJDIR=${.OBJDIR}
75.endif
76# apparently we can live with it
77# make sure we know what we have
78.OBJDIR: ${.CURDIR}
79.endif
80.endif
81.endif
82