share/mk/sys.clean-env.mk

   1 # $Id: sys.clean-env.mk,v 1.21 2016/02/18 21:16:40 sjg Exp $
   2 #
   3 #       @(#) Copyright (c) 2009, Simon J. Gerraty
   4 #
   5 #       This file is provided in the hope that it will
   6 #       be of use.  There is absolutely NO WARRANTY.
   7 #       Permission to copy, redistribute or otherwise
   8 #       use this file is hereby granted provided that
   9 #       the above copyright notice and this notice are
  10 #       left intact.
  11 #
  12 #       Please send copies of changes and bug-fixes to:
  13 #       sjg@crufty.net
  14 #
  15
  16 # This makefile would normally be included by sys.env.mk
  17
  18 # The variables used by this makefile include:
  19 #
  20 # MAKE_ENV_SAVE_VAR_LIST
  21 #       The actuall list of variables from the environment that will be
  22 #       preserved.
  23 # MAKE_ENV_SAVE_PREFIX_LIST
  24 #       A list of prefixes to match against the environment - the results
  25 #       are added to MAKE_ENV_SAVE_VAR_LIST after being filtered by...
  26 # MAKE_ENV_SAVE_EXCLUDE_LIST
  27 #       A list of words or patterns which is turned into a list of :N
  28 #       modifiers.
  29
  30 .if ${.MAKE.LEVEL} == 0 && ${MAKE_VERSION} >= 20100606
  31 # We save any env var that starts with the words in MAKE_ENV_SAVE_PREFIX_LIST.
  32 # This gets expanded to an egrep expression like '^(A|B|C...)'
  33 # and added to MAKE_ENV_SAVE_VAR_LIST below.
  34 # If any of these end up being too greedy, MAKE_ENV_SAVE_EXCLUDE_LIST
  35 # can be used to filter.
  36 MAKE_ENV_SAVE_PREFIX_LIST += \
  37         CCACHE \
  38         CVS \
  39         DEBUG \
  40         DISTCC \
  41         HOST \
  42         MACHINE \
  43         MAKE \
  44         MK \
  45         NEED_ \
  46         SB_ \
  47         SSH \
  48         SVN \
  49         USE_ \
  50         WITH_ \
  51         WITHOUT_ \
  52
  53
  54 # This could be a list of vars or patterns to explicitly exclude.
  55 MAKE_ENV_SAVE_EXCLUDE_LIST ?= _
  56
  57 # This is the actual list that we will save
  58 # HOME is probably something worth clobbering eg.
  59 # HOME=/var/empty
  60 MAKE_ENV_SAVE_VAR_LIST += \
  61         HOME \
  62         LOGNAME \
  63         OBJROOT \
  64         OBJTOP \
  65         PATH \
  66         SB \
  67         SRCTOP \
  68         USER \
  69         ${_env_vars:${MAKE_ENV_SAVE_EXCLUDE_LIST:${M_ListToSkip}}}
  70
  71 _env_vars != env | egrep '^(${MAKE_ENV_SAVE_PREFIX_LIST:ts|})' | sed 's,=.*,,'; echo
  72
  73 _export_list =
  74 .for v in ${MAKE_ENV_SAVE_VAR_LIST:O:u}
  75 .if defined($v)
  76 _export_list += $v
  77 # Save current value
  78 $v := ${$v}
  79 .endif
  80 .endfor
  81
  82 # Now, clobber the environment
  83 .unexport-env
  84
  85 # This is a list of vars that we handle specially below
  86 _tricky_env_vars = MAKEOBJDIR OBJTOP
  87 # Export our selection - sans tricky ones
  88 .export ${_export_list:${_tricky_env_vars:${M_ListToSkip}}}
  89
  90 # This next bit may need tweaking
  91 # if you don't happen to like the way I set it.
  92 .if defined(MAKEOBJDIR)
  93 # We are going to set this to the equivalent of the shell's
  94 # MAKEOBJDIR='${.CURDIR:S,${SRCTOP},${OBJTOP},}'
  95 _srctop := ${SRCTOP:U${SB_SRC:U${SB}/src}}
  96 _objroot := ${OBJROOT:U${SB_OBJROOT:U${SB}/${SB_OBJPREFIX}}}
  97 .if ${MAKE_VERSION} < 20160218
  98 _objtop := ${OBJTOP:U${_objroot}${MACHINE}}
  99 # Take care of ${MACHINE}
 100 .if ${MACHINE} == "host" || ${OBJTOP} == ${HOST_OBJTOP:Uno}
 101 OBJTOP = ${_objtop:S,${HOST_TARGET}$,\${MACHINE},}
 102 .else
 103 OBJTOP = ${_objtop:S,${MACHINE}$,\${MACHINE},}
 104 .endif
 105 # Export like this
 106 MAKEOBJDIR = $${.CURDIR:S,${_srctop},$${OBJTOP},}
 107 #.info ${MAKE_SAVE_ENV_VARS _srctop _objroot _objtop OBJTOP MAKEOBJDIR:L:@v@${.newline}$v=${$v}@}
 108
 109 # Export these as-is, and do not track...
 110 # otherwise the environment will be ruined when we evaluate them below.
 111 .export-env ${_tricky_env_vars}
 112
 113 # Now evaluate for ourselves
 114 .for v in ${_tricky_env_vars}
 115 $v := ${$v}
 116 .endfor
 117 .else
 118 # we cannot use the '$$' trick, anymore
 119 # but we can export a literal (unexpanded) value
 120 SRCTOP := ${_srctop}
 121 OBJROOT := ${_objroot}
 122 OBJTOP = ${OBJROOT}${MACHINE}
 123 MAKEOBJDIR = ${.CURDIR:S,${SRCTOP},${OBJTOP},}
 124 .export-literal SRCTOP OBJROOT ${_tricky_env_vars}
 125 .endif
 126 #.info ${_tricky_env_vars:@v@${.newline}$v=${$v}@}
 127 #showenv:
 128 #       @env | egrep 'OBJ|SRC'
 129 .endif                          # MAKEOBJDIR
 130 .endif                          # level 0