--- /dev/null
+# The functions in this file provide support for relocatability of
+# Perl scripts. They should be included near the beginning of each
+# Perl script in a relocatable program, by adding @relocatable_pl@
+# and causing the script to be expanded with AC_CONFIG_FILES. A
+# small amount of additional code must be added and adapted to the
+# package by hand; see doc/relocatable-maint.texi (in Gnulib) for
+# details.
+#
+# This code is based on relocatable.sh.in, and design changes (and
+# bugs) should probably be cross-checked with it.
+#
+# Copyright (C) 2013 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 3 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 <http://www.gnu.org/licenses/>.
+#
+
+use Config;
+use File::Basename;
+use File::Spec::Functions;
+use Cwd 'realpath';
+
+# Support for relocatability.
+sub find_curr_installdir {
+ # Determine curr_installdir, even taking into account symlinks.
+ my $curr_executable = $0;
+ my $basename = basename($0);
+ if ($curr_executable eq $basename) {
+ LOOP: for my $dir (split /$Config{path_sep}/, $ENV{PATH}) {
+ $dir = "." unless $dir;
+ for my $ext ('') {
+ my $filename = catfile($dir, "$curr_executable$ext");
+ if (-f $filename) {
+ $curr_executable = $filename;
+ last LOOP;
+ }
+ }
+ }
+ }
+ # Resolve symlinks and canonicalize.
+ return realpath(dirname($curr_executable));
+}
+sub find_prefixes {
+ # Compute the original/current installation prefixes by stripping the
+ # trailing directories off the original/current installation directories.
+ my ($orig_installprefix, $curr_installprefix) = @_;
+ my $orig_last = basename($orig_installprefix);
+ my $curr_last = basename($curr_installprefix);
+ if ($orig_last && $curr_last && $orig_last eq $curr_last) {
+ $orig_installprefix = dirname($orig_installprefix);
+ $curr_installprefix = dirname($curr_installprefix);
+ }
+ return $orig_installprefix, $curr_installprefix;
+}
@code{sysconfdir} and @code{some_datadir}, transform those variables
that you need.
+@item
+If your package installs Perl scripts, also import the
+@code{relocatable-perl} module. Then, near the beginning of each
+Perl script that your package installs, add the following:
+
+@example
+@@relocatable_pl@@
+if ("@@RELOCATABLE@@" eq "yes") {
+ my $exec_prefix = "@@exec_prefix@@";
+ my $orig_installdir = "@@bindir@@"; # see Makefile.am's *_SCRIPTS variables
+ my ($orig_installprefix, $curr_installprefix) = find_prefixes($orig_installdir, find_curr_installdir());
+ sub relocate { # the subroutine is defined whether or not the enclosing block is executed
+ my ($dir) = @@_;
+ if ("@@RELOCATABLE@@" eq "yes") {
+ $dir =~ s%^$orig_installprefix/%$curr_installprefix/%;
+ $dir =~ s,/$,,;
+ }
+ return $dir;
+ }
+}
+
+# Get some relocated directory names.
+$sysconfdir = relocate("@@sysconfdir@@");
+$some_datadir = relocate(@@datadir@@/something");
+@end example
+
+You must adapt the definition of @code{$orig_installdir}, depending on
+where the script gets installed. Also, at the end, instead of
+@code{sysconfdir} and @code{some_datadir}, transform those variables
+that you need.
+
@item
In your @file{Makefile.am}, for every program @command{foo} that gets
installed in, say, @file{$(bindir)}, you add:
--- /dev/null
+Description:
+Help make Perl scripts relocatable, that is, to allow them to
+function properly when copied to an arbitrary directory.
+
+Files:
+doc/relocatable.texi
+build-aux/relocatable.pl.in
+m4/relocatable-lib.m4
+
+Depends-on:
+
+configure.ac:
+AC_REQUIRE([gl_RELOCATABLE_NOP])
+relocatable_pl=$ac_aux_dir/relocatable.pl.in
+AC_SUBST_FILE([relocatable_pl])
+
+Makefile.am:
+
+Include:
+
+License:
+GPL
+
+Maintainer:
+Bruno Haible, Ben Pfaff, Reuben Thomas