dnl $Id$
dnl

dnl ----------------------------------------------------------------
dnl From gcc's libiberty aclocal.m4

dnl See whether we need a declaration for a function.
AC_DEFUN([libiberty_NEED_DECLARATION],
[
  AC_MSG_CHECKING([whether $1 must be declared])
  AC_CACHE_VAL(libiberty_cv_decl_needed_$1,
  [AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
dnl includes
[[#include "confdefs.h"
  #include <stdio.h>
  #ifdef HAVE_STRING_H
    #include <string.h>
  #else
    #ifdef HAVE_STRINGS_H
      #include <strings.h>
    #endif
  #endif
  #ifdef HAVE_STDLIB_H
    #include <stdlib.h>
  #endif
  #ifdef HAVE_UNISTD_H
    #include <unistd.h>
  #endif]],
dnl function(s) to check
[[char *(*pfn) = (char *(*)) $1]]
)],
dnl check was successful
[libiberty_cv_decl_needed_$1=no],
dnl check was not successful
[libiberty_cv_decl_needed_$1=yes]
)]
)
  AC_MSG_RESULT([$libiberty_cv_decl_needed_$1])
  if test $libiberty_cv_decl_needed_$1 = yes; then
      AC_DEFINE([NEED_DECLARATION_]translit($1, [a-z], [A-Z]), 1,
                [Define if $1 is not declared in system header files.])
fi
])

dnl ----------------------------------------------------------------
dnl From http://autoconf-archive.cryp.to/adl_compute_relative_paths.html
dnl and http://autoconf-archive.cryp.to/adl_normalize_path.html
dnl
dnl the adl_* functions which follow have the following copyright:
dnl
dnl Copyright © 2006 Alexandre Duret-Lutz <adl@gnu.org>

dnl 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 of the License, or (at your option) any later version.

dnl 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.

dnl 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

dnl As a special exception, the respective Autoconf Macro's copyright owner gives unlimited permission to copy, distribute and modify the configure scripts that are the output of Autoconf when processing the Macro. 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 the Macro appear in them. The GNU General Public License (GPL) does govern all other use of the material that constitutes the Autoconf Macro.

dnl This special exception to the GPL applies to versions of the Autoconf Macro released by the Autoconf Macro Archive. When you make and distribute a modified version of the Autoconf Macro, you may extend this special exception to the GPL to apply to your modified version as well.

AC_DEFUN([adl_NORMALIZE_PATH],
[case ":[$]$1:" in
# change empty paths to '.'
  ::) $1='.' ;;
# strip trailing slashes
  :*[[\\/]]:) $1=`echo "[$]$1" | sed 's,[[\\/]]*[$],,'` ;;
  :*:) ;;
esac
# squeze repeated slashes
case ifelse($2,,"[$]$1",$2) in
# if the path contains any backslashes, turn slashes into backslashes
 *\\*) $1=`echo "[$]$1" | sed 's,\(.\)[[\\/]][[\\/]]*,\1\\\\\\\\,g'` ;;
# if the path contains slashes, also turn backslashes into slashes
 *) $1=`echo "[$]$1" | sed 's,\(.\)[[\\/]][[\\/]]*,\1/,g'` ;;
esac])


AC_DEFUN([adl_COMPUTE_RELATIVE_PATHS],
[for _lcl_i in $1; do
  _lcl_from=\[$]`echo "[$]_lcl_i" | sed 's,:.*$,,'`
  _lcl_to=\[$]`echo "[$]_lcl_i" | sed 's,^[[^:]]*:,,' | sed 's,:[[^:]]*$,,'`
  _lcl_result_var=`echo "[$]_lcl_i" | sed 's,^.*:,,'`
  adl_RECURSIVE_EVAL([[$]_lcl_from], [_lcl_from])
  adl_RECURSIVE_EVAL([[$]_lcl_to], [_lcl_to])
  _lcl_notation="$_lcl_from$_lcl_to"
  adl_NORMALIZE_PATH([_lcl_from],['/'])
  adl_NORMALIZE_PATH([_lcl_to],['/'])
  adl_COMPUTE_RELATIVE_PATH([_lcl_from], [_lcl_to], [_lcl_result_tmp])
  adl_NORMALIZE_PATH([_lcl_result_tmp],["[$]_lcl_notation"])
  eval $_lcl_result_var='[$]_lcl_result_tmp'
done])

## Note:
## *****
## The following helper macros are too fragile to be used out
## of adl_COMPUTE_RELATIVE_PATHS (mainly because they assume that
## paths are normalized), that's why I'm keeping them in the same file.
## Still, some of them maybe worth to reuse.

dnl adl_COMPUTE_RELATIVE_PATH(FROM, TO, RESULT)
dnl ===========================================
dnl Compute the relative path to go from $FROM to $TO and set the value
dnl of $RESULT to that value.  This function work on raw filenames
dnl (for instead it will considerate /usr//local and /usr/local as
dnl two distinct paths), you should really use adl_COMPUTE_REALTIVE_PATHS
dnl instead to have the paths sanitized automatically.
dnl
dnl For instance:
dnl    first_dir=/somewhere/on/my/disk/bin
dnl    second_dir=/somewhere/on/another/disk/share
dnl    adl_COMPUTE_RELATIVE_PATH(first_dir, second_dir, first_to_second)
dnl will set $first_to_second to '../../../another/disk/share'.
AC_DEFUN([adl_COMPUTE_RELATIVE_PATH],
[adl_COMPUTE_COMMON_PATH([$1], [$2], [_lcl_common_prefix])
adl_COMPUTE_BACK_PATH([$1], [_lcl_common_prefix], [_lcl_first_rel])
adl_COMPUTE_SUFFIX_PATH([$2], [_lcl_common_prefix], [_lcl_second_suffix])
$3="[$]_lcl_first_rel[$]_lcl_second_suffix"])


dnl adl_COMPUTE_COMMON_PATH(LEFT, RIGHT, RESULT)
dnl ============================================
dnl Compute the common path to $LEFT and $RIGHT and set the result to $RESULT.
dnl
dnl For instance:
dnl    first_path=/somewhere/on/my/disk/bin
dnl    second_path=/somewhere/on/another/disk/share
dnl    adl_COMPUTE_COMMON_PATH(first_path, second_path, common_path)
dnl will set $common_path to '/somewhere/on'.
AC_DEFUN([adl_COMPUTE_COMMON_PATH],
[$3=''
_lcl_second_prefix_match=''
while test "[$]_lcl_second_prefix_match" != 0; do
  _lcl_first_prefix=`expr "x[$]$1" : "x\([$]$3/*[[^/]]*\)"`
  _lcl_second_prefix_match=`expr "x[$]$2" : "x[$]_lcl_first_prefix"`
  if test "[$]_lcl_second_prefix_match" != 0; then
    if test "[$]_lcl_first_prefix" != "[$]$3"; then
      $3="[$]_lcl_first_prefix"
    else
      _lcl_second_prefix_match=0
    fi
  fi
done])

dnl adl_COMPUTE_SUFFIX_PATH(PATH, SUBPATH, RESULT)
dnl ==============================================
dnl Substrack $SUBPATH from $PATH, and set the resulting suffix
dnl (or the empty string if $SUBPATH is not a subpath of $PATH)
dnl to $RESULT.
dnl
dnl For instace:
dnl    first_path=/somewhere/on/my/disk/bin
dnl    second_path=/somewhere/on
dnl    adl_COMPUTE_SUFFIX_PATH(first_path, second_path, common_path)
dnl will set $common_path to '/my/disk/bin'.
AC_DEFUN([adl_COMPUTE_SUFFIX_PATH],
[$3=`expr "x[$]$1" : "x[$]$2/*\(.*\)"`])

dnl adl_COMPUTE_BACK_PATH(PATH, SUBPATH, RESULT)
dnl ============================================
dnl Compute the relative path to go from $PATH to $SUBPATH, knowing that
dnl $SUBPATH is a subpath of $PATH (any other words, only repeated '../'
dnl should be needed to move from $PATH to $SUBPATH) and set the value
dnl of $RESULT to that value.  If $SUBPATH is not a subpath of PATH,
dnl set $RESULT to the empty string.
dnl
dnl For instance:
dnl    first_path=/somewhere/on/my/disk/bin
dnl    second_path=/somewhere/on
dnl    adl_COMPUTE_BACK_PATH(first_path, second_path, back_path)
dnl will set $back_path to '../../../'.
AC_DEFUN([adl_COMPUTE_BACK_PATH],
[adl_COMPUTE_SUFFIX_PATH([$1], [$2], [_lcl_first_suffix])
$3=''
_lcl_tmp='xxx'
while test "[$]_lcl_tmp" != ''; do
  _lcl_tmp=`expr "x[$]_lcl_first_suffix" : "x[[^/]]*/*\(.*\)"`
  if test "[$]_lcl_first_suffix" != ''; then
     _lcl_first_suffix="[$]_lcl_tmp"
     $3="../[$]$3"
  fi
done])


dnl adl_RECURSIVE_EVAL(VALUE, RESULT)
dnl =================================
dnl Interpolate the VALUE in loop until it doesn't change,
dnl and set the result to $RESULT.
dnl WARNING: It's easy to get an infinite loop with some unsane input.
AC_DEFUN([adl_RECURSIVE_EVAL],
[_lcl_receval="$1"
$2=`(test "x$prefix" = xNONE && prefix="$ac_default_prefix"
     test "x$exec_prefix" = xNONE && exec_prefix="${prefix}"
     _lcl_receval_old=''
     while test "[$]_lcl_receval_old" != "[$]_lcl_receval"; do
       _lcl_receval_old="[$]_lcl_receval"
       eval _lcl_receval="\"[$]_lcl_receval\""
     done
     echo "[$]_lcl_receval")`])