programs.m4

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# This file is part of Autoconf.                       -*- Autoconf -*-
# Checking for programs.

# Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
# 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2, or (at your option)
# any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA.

# As a special exception, the Free Software Foundation gives unlimited
# permission to copy, distribute and modify the configure scripts that
# are the output of Autoconf.  You need not follow the terms of the GNU
# General Public License when using or distributing such scripts, even
# though portions of the text of Autoconf appear in them.  The GNU
# General Public License (GPL) does govern all other use of the material
# that constitutes the Autoconf program.
#
# Certain portions of the Autoconf source text are designed to be copied
# (in certain cases, depending on the input) into the output of
# Autoconf.  We call these the "data" portions.  The rest of the Autoconf
# source text consists of comments plus executable code that decides which
# of the data portions to output in any given case.  We call these
# comments and executable code the "non-data" portions.  Autoconf never
# copies any of the non-data portions into its output.
#
# This special exception to the GPL applies to versions of Autoconf
# released by the Free Software Foundation.  When you make and
# distribute a modified version of Autoconf, you may extend this special
# exception to the GPL to apply to your modified version as well, *unless*
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# of the text that was the non-data portion of the version that you started
# with.  (In other words, unless your change moves or copies text from
# the non-data portions to the data portions.)  If your modification has
# such potential, you must delete any notice of this special exception
# to the GPL from your modified version.
#
# Written by David MacKenzie, with help from
# Franc,ois Pinard, Karl Berry, Richard Pixley, Ian Lance Taylor,
# Roland McGrath, Noah Friedman, david d zuhn, and many others.


## ----------------------------- ##
## Generic checks for programs.  ##
## ----------------------------- ##


# _AC_CHECK_PROG(VARIABLE, PROG-TO-CHECK-FOR,
#               [VALUE-IF-FOUND], [VALUE-IF-NOT-FOUND],
#               [PATH], [REJECT])
# -----------------------------------------------------
AC_DEFUN([_AC_CHECK_PROG],
[# Extract the first word of "$2", so it can be a program name with args.
set dummy $2; ac_word=$[2]
AC_MSG_CHECKING([for $ac_word])
AC_CACHE_VAL(ac_cv_prog_$1,
[if test -n "$$1"; then
  ac_cv_prog_$1="$$1" # Let the user override the test.
else
m4_ifvaln([$6],
[  ac_prog_rejected=no])dnl
_AS_PATH_WALK([$5],
[for ac_exec_ext in '' $ac_executable_extensions; do
  if AS_EXECUTABLE_P(["$as_dir/$ac_word$ac_exec_ext"]); then
m4_ifvaln([$6],
[    if test "$as_dir/$ac_word$ac_exec_ext" = "$6"; then
       ac_prog_rejected=yes
       continue
     fi])dnl
    ac_cv_prog_$1="$3"
    _AS_ECHO_LOG([found $as_dir/$ac_word$ac_exec_ext])
    break 2
  fi
done])
m4_ifvaln([$6],
[if test $ac_prog_rejected = yes; then
  # We found a bogon in the path, so make sure we never use it.
  set dummy $ac_cv_prog_$1
  shift
  if test $[@%:@] != 0; then
    # We chose a different compiler from the bogus one.
    # However, it has the same basename, so the bogon will be chosen
    # first if we set $1 to just the basename; use the full file name.
    shift
    ac_cv_prog_$1="$as_dir/$ac_word${1+' '}$[@]"
m4_if([$2], [$4],
[  else
    # Default is a loser.
    AC_MSG_ERROR([$1=$6 unacceptable, but no other $4 found in dnl
m4_default([$5], [\$PATH])])
])dnl
  fi
fi])dnl
dnl If no 4th arg is given, leave the cache variable unset,
dnl so AC_CHECK_PROGS will keep looking.
m4_ifvaln([$4],
[  test -z "$ac_cv_prog_$1" && ac_cv_prog_$1="$4"])dnl
fi])dnl
$1=$ac_cv_prog_$1
if test -n "$$1"; then
  AC_MSG_RESULT([$$1])
else
  AC_MSG_RESULT([no])
fi
])# _AC_CHECK_PROG


# AC_CHECK_PROG(VARIABLE, PROG-TO-CHECK-FOR,
#               [VALUE-IF-FOUND], [VALUE-IF-NOT-FOUND],
#               [PATH], [REJECT])
# -----------------------------------------------------
AC_DEFUN([AC_CHECK_PROG],
[_AC_CHECK_PROG($@)
AC_SUBST([$1])dnl
])


# AC_CHECK_PROGS(VARIABLE, PROGS-TO-CHECK-FOR, [VALUE-IF-NOT-FOUND],
#                [PATH])
# ------------------------------------------------------------------
AC_DEFUN([AC_CHECK_PROGS],
[for ac_prog in $2
do
  AC_CHECK_PROG([$1], [$ac_prog], [$ac_prog], , [$4])
  test -n "$$1" && break
done
m4_ifvaln([$3], [test -n "$$1" || $1="$3"])])


# _AC_PATH_PROG(VARIABLE, PROG-TO-CHECK-FOR, [VALUE-IF-NOT-FOUND], [PATH])
# ------------------------------------------------------------------------
AC_DEFUN([_AC_PATH_PROG],
[# Extract the first word of "$2", so it can be a program name with args.
set dummy $2; ac_word=$[2]
AC_MSG_CHECKING([for $ac_word])
AC_CACHE_VAL([ac_cv_path_$1],
[case $$1 in
  [[\\/]]* | ?:[[\\/]]*)
  ac_cv_path_$1="$$1" # Let the user override the test with a path.
  ;;
  *)
  _AS_PATH_WALK([$4],
[for ac_exec_ext in '' $ac_executable_extensions; do
  if AS_EXECUTABLE_P(["$as_dir/$ac_word$ac_exec_ext"]); then
    ac_cv_path_$1="$as_dir/$ac_word$ac_exec_ext"
    _AS_ECHO_LOG([found $as_dir/$ac_word$ac_exec_ext])
    break 2
  fi
done])
dnl If no 3rd arg is given, leave the cache variable unset,
dnl so AC_PATH_PROGS will keep looking.
m4_ifvaln([$3],
[  test -z "$ac_cv_path_$1" && ac_cv_path_$1="$3"])dnl
  ;;
esac])dnl
$1=$ac_cv_path_$1
if test -n "$$1"; then
  AC_MSG_RESULT([$$1])
else
  AC_MSG_RESULT([no])
fi
])# _AC_PATH_PROG


# AC_PATH_PROG(VARIABLE, PROG-TO-CHECK-FOR, [VALUE-IF-NOT-FOUND], [PATH])
# -----------------------------------------------------------------------
AC_DEFUN([AC_PATH_PROG],
[_AC_PATH_PROG($@)
AC_SUBST([$1])dnl
])


# AC_PATH_PROGS(VARIABLE, PROGS-TO-CHECK-FOR, [VALUE-IF-NOT-FOUND],
#               [PATH])
# -----------------------------------------------------------------
AC_DEFUN([AC_PATH_PROGS],
[for ac_prog in $2
do
  AC_PATH_PROG([$1], [$ac_prog], , [$4])
  test -n "$$1" && break
done
m4_ifvaln([$3], [test -n "$$1" || $1="$3"])dnl
])




## -------------------------- ##
## Generic checks for tools.  ##
## -------------------------- ##


# AC_CHECK_TOOL_PREFIX
# --------------------
AU_DEFUN([AC_CHECK_TOOL_PREFIX])


# _AC_TOOL_WARN
# -------------
AC_DEFUN([_AC_TOOL_WARN],
[case $cross_compiling:$ac_tool_warned in
yes:)
AC_MSG_WARN([In the future, Autoconf will not detect cross-tools
whose name does not start with the host triplet.  If you think this
configuration is useful to you, please write to [e-mail].])
ac_tool_warned=yes ;;
esac])

# AC_PATH_TOOL(VARIABLE, PROG-TO-CHECK-FOR, [VALUE-IF-NOT-FOUND], [PATH])
# -----------------------------------------------------------------------
# (Use different variables $1 and ac_pt_$1 so that cache vars don't conflict.)
AC_DEFUN([AC_PATH_TOOL],
[if test -n "$ac_tool_prefix"; then
  AC_PATH_PROG([$1], [${ac_tool_prefix}$2], , [$4])
fi
if test -z "$ac_cv_path_$1"; then
  ac_pt_$1=$$1
  _AC_PATH_PROG([ac_pt_$1], [$2], [], [$4])
  if test "x$ac_pt_$1" = x; then
    $1="$3"
  else
    _AC_TOOL_WARN
    $1=$ac_pt_$1
  fi
else
  $1="$ac_cv_path_$1"
fi
])# AC_PATH_TOOL


# AC_CHECK_TOOL(VARIABLE, PROG-TO-CHECK-FOR, [VALUE-IF-NOT-FOUND], [PATH])
# ------------------------------------------------------------------------
# (Use different variables $1 and ac_ct_$1 so that cache vars don't conflict.)
AC_DEFUN([AC_CHECK_TOOL],
[if test -n "$ac_tool_prefix"; then
  AC_CHECK_PROG([$1], [${ac_tool_prefix}$2], [${ac_tool_prefix}$2], , [$4])
fi
if test -z "$ac_cv_prog_$1"; then
  ac_ct_$1=$$1
  _AC_CHECK_PROG([ac_ct_$1], [$2], [$2], [], [$4])
  if test "x$ac_ct_$1" = x; then
    $1="$3"
  else
    _AC_TOOL_WARN
    $1=$ac_ct_$1
  fi
else
  $1="$ac_cv_prog_$1"
fi
])# AC_CHECK_TOOL


# AC_CHECK_TOOLS(VARIABLE, PROGS-TO-CHECK-FOR, [VALUE-IF-NOT-FOUND],
#                [PATH])
# ------------------------------------------------------------------
# Check for each tool in PROGS-TO-CHECK-FOR with the cross prefix. If
# none can be found with a cross prefix, then use the first one that
# was found without the cross prefix.
AC_DEFUN([AC_CHECK_TOOLS],
[if test -n "$ac_tool_prefix"; then
  for ac_prog in $2
  do
    AC_CHECK_PROG([$1],
		  [$ac_tool_prefix$ac_prog], [$ac_tool_prefix$ac_prog],,
		  [$4])
    test -n "$$1" && break
  done
fi
if test -z "$$1"; then
  ac_ct_$1=$$1
  AC_CHECK_PROGS([ac_ct_$1], [$2], [], [$4])
  if test "x$ac_ct_$1" = x; then
    $1="$3"
  else
    _AC_TOOL_WARN
    $1=$ac_ct_$1
  fi
fi
])# AC_CHECK_TOOLS


# AC_PATH_TARGET_TOOL(VARIABLE, PROG-TO-CHECK-FOR, [VALUE-IF-NOT-FOUND], [PATH])
# -----------------------------------------------------------------------
# (Use different variables $1 and ac_pt_$1 so that cache vars don't conflict.)
AC_DEFUN([AC_PATH_TARGET_TOOL],
[AC_BEFORE([$0], [AC_CANONICAL_TARGET])dnl
AC_PATH_PROG([$1], [$target_alias-$2], , [$4])
if test -z "$ac_cv_path_$1"; then
  if test "$build" = "$target"; then
    ac_pt_$1=$$1
    _AC_PATH_PROG([ac_pt_$1], [$2], [$3], [$4])
    $1=$ac_pt_$1
  else
    $1="$3"
  fi
else
  $1="$ac_cv_path_$1"
fi
])# AC_PATH_TARGET_TOOL


# AC_CHECK_TARGET_TOOL(VARIABLE, PROG-TO-CHECK-FOR, [VALUE-IF-NOT-FOUND], [PATH])
# ------------------------------------------------------------------------
# (Use different variables $1 and ac_ct_$1 so that cache vars don't conflict.)
AC_DEFUN([AC_CHECK_TARGET_TOOL],
[AC_BEFORE([$0], [AC_CANONICAL_TARGET])dnl
AC_CHECK_PROG([$1], [$target_alias-$2], [$target_alias-$2], , [$4])
if test -z "$ac_cv_prog_$1"; then
  if test "$build" = "$target"; then
    ac_ct_$1=$$1
    _AC_CHECK_PROG([ac_ct_$1], [$2], [$2], [$3], [$4])
    $1=ac_ct_$1
  else
    $1="$3"
  fi
else
  $1="$ac_cv_prog_$1"
fi
])# AC_CHECK_TARGET_TOOL


# AC_CHECK_TARGET_TOOLS(VARIABLE, PROGS-TO-CHECK-FOR, [VALUE-IF-NOT-FOUND],
#	                [PATH])
# ------------------------------------------------------------------
# Check for each tool in PROGS-TO-CHECK-FOR with the cross prefix. If
# none can be found with a cross prefix, then use the first one that
# was found without the cross prefix.
AC_DEFUN([AC_CHECK_TARGET_TOOLS],
[AC_BEFORE([$0], [AC_CANONICAL_TARGET])dnl
for ac_prog in $2
do
  AC_CHECK_PROG([$1],
		[$target_alias-$ac_prog], [$target_alias-$ac_prog],,
		[$4])
  test -n "$$1" && break
done
if test -z "$$1"; then
  if test "$build" = "$target"; then
    ac_ct_$1=$$1
    AC_CHECK_PROGS([ac_ct_$1], [$2], [$3], [$4])
    $1=$ac_ct_$1
  else
    $1="$3"
  fi
fi
])# AC_CHECK_TARGET_TOOLS



## ---------------- ##
## Specific tests.  ##
## ---------------- ##

# Please, keep this section sorted.
# (But of course when keeping related things together).

# Check for gawk first since it's generally better.
AN_MAKEVAR([AWK],  [AC_PROG_AWK])
AN_PROGRAM([awk],  [AC_PROG_AWK])
AN_PROGRAM([gawk], [AC_PROG_AWK])
AN_PROGRAM([mawk], [AC_PROG_AWK])
AN_PROGRAM([nawk], [AC_PROG_AWK])
AC_DEFUN([AC_PROG_AWK],
[AC_CHECK_PROGS(AWK, gawk mawk nawk awk, )])


# AC_PROG_EGREP
# -------------
AC_DEFUN([AC_PROG_EGREP],
[AC_REQUIRE([AC_PROG_GREP])dnl
AC_CACHE_CHECK([for egrep], ac_cv_path_EGREP,
   [if echo a | $GREP -E '(a|b)' >/dev/null 2>&1
   then ac_cv_path_EGREP="$GREP -E"
   else
     _AC_PROG_GREP(EGREP, egrep, ['EGREP$'])
   fi])
 EGREP="$ac_cv_path_EGREP"
 AC_SUBST([EGREP])
])# AC_PROG_EGREP


# AC_PROG_FGREP
# -------------
AC_DEFUN([AC_PROG_FGREP],
[AC_REQUIRE([AC_PROG_GREP])dnl
AC_CACHE_CHECK([for fgrep], ac_cv_path_FGREP,
   [if echo 'ab*c' | $GREP -F 'ab*c' >/dev/null 2>&1
   then ac_cv_path_FGREP="$GREP -F"
   else
     _AC_PROG_GREP(FGREP, fgrep, [FGREP])
   fi])
 FGREP="$ac_cv_path_FGREP"
 AC_SUBST([FGREP])
])# AC_PROG_FGREP


# AC_PROG_GREP
# ------------
# Check for a fully functional grep program that handles
# the longest lines possible and which respects multiple -e options.
# Prefer GNU grep if found.
AC_DEFUN([AC_PROG_GREP],
[AC_CACHE_CHECK([for grep that handles long lines and -e], ac_cv_path_GREP,
   [_$0(GREP, [grep ggrep], [-e 'GREP$' -e '-(cannot match)-'])])
 GREP="$ac_cv_path_GREP"
 AC_SUBST([GREP])
])


# _AC_PROG_GREP(VARIABLE, PROGNAME-LIST, PROG-ARGUMENTS)
# ------------------------------------------------------
# Solaris 9 /usr/xpg4/bin/*grep is suitable, but /usr/bin/*grep lacks -e.
# AIX silently truncates long lines before matching.
# NeXT understands only one -e and truncates long lines.
m4_define([_AC_PROG_GREP],
[_AC_PATH_PROG_FEATURE_CHECK([$1], [$2],
	[_AC_FEATURE_CHECK_LENGTH([ac_path_$1], [ac_cv_path_$1],
		["$ac_path_$1" $3], [$1])], [$PATH$PATH_SEPARATOR/usr/xpg4/bin])
])


# _AC_PATH_PROG_FEATURE_CHECK(VARIABLE, PROGNAME-LIST, FEATURE-TEST, [PATH])