# ============================================================================== # https://www.gnu.org/software/autoconf-archive/ax_compute_relative_paths.html # ============================================================================== # # SYNOPSIS # # AX_COMPUTE_RELATIVE_PATHS(PATH_LIST) # # DESCRIPTION # # PATH_LIST is a space-separated list of colon-separated triplets of the # form 'FROM:TO:RESULT'. This function iterates over these triplets and # set $RESULT to the relative path from $FROM to $TO. Note that $FROM and # $TO needs to be absolute filenames for this macro to success. # # For instance, # # first=/usr/local/bin # second=/usr/local/share # AX_COMPUTE_RELATIVE_PATHS([first:second:fs second:first:sf]) # # $fs is set to ../share # # $sf is set to ../bin # # $FROM and $TO are both eval'ed recursively and normalized, this means # that you can call this macro with autoconf's dirnames like `prefix' or # `datadir'. For example: # # AX_COMPUTE_RELATIVE_PATHS([bindir:datadir:bin_to_data]) # # AX_COMPUTE_RELATIVE_PATHS should also works with DOS filenames. # # You may want to use this macro in order to make your package # relocatable. Instead of hardcoding $datadir into your programs just # encode $bin_to_data and try to determine $bindir at run-time. # # This macro requires AX_NORMALIZE_PATH and AX_RECURSIVE_EVAL. # # LICENSE # # Copyright (c) 2008 Alexandre Duret-Lutz <adl@gnu.org> # # 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. # # 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, see <https://www.gnu.org/licenses/>. # # 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. # # This special exception to the GPL applies to versions of the Autoconf # Macro released by the Autoconf 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. #serial 12 AU_ALIAS([ADL_COMPUTE_RELATIVE_PATHS], [AX_COMPUTE_RELATIVE_PATHS]) AC_DEFUN([AX_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,^.*:,,'` AX_RECURSIVE_EVAL([[$]_lcl_from], [_lcl_from]) AX_RECURSIVE_EVAL([[$]_lcl_to], [_lcl_to]) _lcl_notation="$_lcl_from$_lcl_to" AX_NORMALIZE_PATH([_lcl_from],['/']) AX_NORMALIZE_PATH([_lcl_to],['/']) AX_COMPUTE_RELATIVE_PATH([_lcl_from], [_lcl_to], [_lcl_result_tmp]) AX_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 AX_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 AX_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 AX_COMPUTE_RELATIVE_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 AX_COMPUTE_RELATIVE_PATH(first_dir, second_dir, first_to_second) dnl will set $first_to_second to '../../../another/disk/share'. AC_DEFUN([AX_COMPUTE_RELATIVE_PATH], [AX_COMPUTE_COMMON_PATH([$1], [$2], [_lcl_common_prefix]) AX_COMPUTE_BACK_PATH([$1], [_lcl_common_prefix], [_lcl_first_rel]) AX_COMPUTE_SUFFIX_PATH([$2], [_lcl_common_prefix], [_lcl_second_suffix]) $3="[$]_lcl_first_rel[$]_lcl_second_suffix"]) dnl AX_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 AX_COMPUTE_COMMON_PATH(first_path, second_path, common_path) dnl will set $common_path to '/somewhere/on'. AC_DEFUN([AX_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 AX_COMPUTE_SUFFIX_PATH(PATH, SUBPATH, RESULT) dnl ============================================== dnl Subtract $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 instance: dnl first_path=/somewhere/on/my/disk/bin dnl second_path=/somewhere/on dnl AX_COMPUTE_SUFFIX_PATH(first_path, second_path, common_path) dnl will set $common_path to '/my/disk/bin'. AC_DEFUN([AX_COMPUTE_SUFFIX_PATH], [$3=`expr "x[$]$1" : "x[$]$2/*\(.*\)"`]) dnl AX_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 AX_COMPUTE_BACK_PATH(first_path, second_path, back_path) dnl will set $back_path to '../../../'. AC_DEFUN([AX_COMPUTE_BACK_PATH], [AX_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])