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Diffstat (limited to 'm4/ax_compute_relative_paths.m4')
-rw-r--r-- | m4/ax_compute_relative_paths.m4 | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/m4/ax_compute_relative_paths.m4 b/m4/ax_compute_relative_paths.m4 new file mode 100644 index 000000000..102470798 --- /dev/null +++ b/m4/ax_compute_relative_paths.m4 @@ -0,0 +1,173 @@ +# ============================================================================== +# 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]) |