1# Check how to create a tarball. -*- Autoconf -*- 2 3# Copyright (C) 2004-2015 Free Software Foundation, Inc. 4# 5# This file is free software; the Free Software Foundation 6# gives unlimited permission to copy and/or distribute it, 7# with or without modifications, as long as this notice is preserved. 8 9# _AM_PROG_TAR(FORMAT) 10# -------------------- 11# Check how to create a tarball in format FORMAT. 12# FORMAT should be one of 'v7', 'ustar', or 'pax'. 13# 14# Substitute a variable $(am__tar) that is a command 15# writing to stdout a FORMAT-tarball containing the directory 16# $tardir. 17# tardir=directory && $(am__tar) > result.tar 18# 19# Substitute a variable $(am__untar) that extract such 20# a tarball read from stdin. 21# $(am__untar) < result.tar 22# 23AC_DEFUN([_AM_PROG_TAR], 24[# Always define AMTAR for backward compatibility. Yes, it's still used 25# in the wild :-( We should find a proper way to deprecate it ... 26AC_SUBST([AMTAR], ['$${TAR-tar}']) 27 28# We'll loop over all known methods to create a tar archive until one works. 29_am_tools='gnutar m4_if([$1], [ustar], [plaintar]) pax cpio none' 30 31m4_if([$1], [v7], 32 [am__tar='$${TAR-tar} chof - "$$tardir"' am__untar='$${TAR-tar} xf -'], 33 34 [m4_case([$1], 35 [ustar], 36 [# The POSIX 1988 'ustar' format is defined with fixed-size fields. 37 # There is notably a 21 bits limit for the UID and the GID. In fact, 38 # the 'pax' utility can hang on bigger UID/GID (see automake bug#8343 39 # and bug#13588). 40 am_max_uid=2097151 # 2^21 - 1 41 am_max_gid=$am_max_uid 42 # The $UID and $GID variables are not portable, so we need to resort 43 # to the POSIX-mandated id(1) utility. Errors in the 'id' calls 44 # below are definitely unexpected, so allow the users to see them 45 # (that is, avoid stderr redirection). 46 am_uid=`id -u || echo unknown` 47 am_gid=`id -g || echo unknown` 48 AC_MSG_CHECKING([whether UID '$am_uid' is supported by ustar format]) 49 if test $am_uid -le $am_max_uid; then 50 AC_MSG_RESULT([yes]) 51 else 52 AC_MSG_RESULT([no]) 53 _am_tools=none 54 fi 55 AC_MSG_CHECKING([whether GID '$am_gid' is supported by ustar format]) 56 if test $am_gid -le $am_max_gid; then 57 AC_MSG_RESULT([yes]) 58 else 59 AC_MSG_RESULT([no]) 60 _am_tools=none 61 fi], 62 63 [pax], 64 [], 65 66 [m4_fatal([Unknown tar format])]) 67 68 AC_MSG_CHECKING([how to create a $1 tar archive]) 69 70 # Go ahead even if we have the value already cached. We do so because we 71 # need to set the values for the 'am__tar' and 'am__untar' variables. 72 _am_tools=${am_cv_prog_tar_$1-$_am_tools} 73 74 for _am_tool in $_am_tools; do 75 case $_am_tool in 76 gnutar) 77 for _am_tar in tar gnutar gtar; do 78 AM_RUN_LOG([$_am_tar --version]) && break 79 done 80 81 # Work around CFEngine redmine #6925 by using --hard-dereference. 82 AM_RUN_LOG([$_am_tar --hard-dereference 2>&1 | grep 'unrecognized option']) 83 # Check if --hard-dereference is supported by this version of GNU Tar 84 if test "$ac_status" -eq 0; then 85 _am_gnutar_hard_dereference=false 86 am__tar="$_am_tar --format=m4_if([$1], [pax], [posix], [$1]) -chf - "'"$$tardir"' 87 am__tar_="$_am_tar --format=m4_if([$1], [pax], [posix], [$1]) -chf - "'"$tardir"' 88 else 89 _am_gnutar_hard_dereference=true 90 am__tar="$_am_tar --format=m4_if([$1], [pax], [posix], [$1]) --hard-dereference -chf - "'"$$tardir"' 91 am__tar_="$_am_tar --format=m4_if([$1], [pax], [posix], [$1]) --hard-dereference -chf - "'"$tardir"' 92 fi 93 94 am__untar="$_am_tar -xf -" 95 ;; 96 plaintar) 97 # Must skip GNU tar: if it does not support --format= it doesn't create 98 # ustar tarball either. 99 (tar --version) >/dev/null 2>&1 && continue 100 am__tar='tar chf - "$$tardir"' 101 am__tar_='tar chf - "$tardir"' 102 am__untar='tar xf -' 103 ;; 104 pax) 105 am__tar='pax -L -x $1 -w "$$tardir"' 106 am__tar_='pax -L -x $1 -w "$tardir"' 107 am__untar='pax -r' 108 ;; 109 cpio) 110 am__tar='find "$$tardir" -print | cpio -o -H $1 -L' 111 am__tar_='find "$tardir" -print | cpio -o -H $1 -L' 112 am__untar='cpio -i -H $1 -d' 113 ;; 114 none) 115 am__tar=false 116 am__tar_=false 117 am__untar=false 118 ;; 119 esac 120 121 # If the value was cached, stop now. We just wanted to have am__tar 122 # and am__untar set. 123 test -n "${am_cv_prog_tar_$1}" && break 124 125 # tar/untar a dummy directory, and stop if the command works. 126 rm -rf conftest.dir 127 mkdir conftest.dir 128 echo GrepMe > conftest.dir/file 129 AM_RUN_LOG([tardir=conftest.dir && eval $am__tar_ >conftest.tar]) 130 rm -rf conftest.dir 131 if test -s conftest.tar; then 132 AM_RUN_LOG([$am__untar <conftest.tar]) 133 AM_RUN_LOG([cat conftest.dir/file]) 134 grep GrepMe conftest.dir/file >/dev/null 2>&1 && break 135 fi 136 done 137 rm -rf conftest.dir 138 139 AC_CACHE_VAL([am_cv_prog_tar_$1], [am_cv_prog_tar_$1=$_am_tool]) 140 AC_MSG_RESULT([$am_cv_prog_tar_$1])]) 141 142 if test $_am_tool = gnutar; then 143 # We've checked already, so we're just printing here 144 AC_MSG_CHECKING([if GNU tar supports --hard-dereference]) 145 if test x$_am_gnutar_hard_dereference = xtrue; then 146 AC_MSG_RESULT([yes]) 147 else 148 AC_MSG_RESULT([no]) 149 fi 150 fi 151 152AC_SUBST([am__tar]) 153AC_SUBST([am__untar]) 154]) # _AM_PROG_TAR 155