t9129: fix UTF-8 locale detection

index b9224bd..ec6ed4f 100755
@@ -69,7 +69,7 @@ do
 	'
 done
 
-if locale -a |grep -q en_US.utf8; then
+if locale -a |grep -q en_US.UTF-8; then
 	test_set_prereq UTF8
 else
 	say "UTF-8 locale not available, test skipped"

index b9224bd..00a273b 100755
@@ -69,7 +69,7 @@ do
 	'
 done
 
-if locale -a |grep -q en_US.utf8; then
+if locale -a |grep -qE '^en_US\.(utf|UTF)-?8$'; then
 	test_set_prereq UTF8
 else
 	say "UTF-8 locale not available, test skipped"

index b9224bd..1e9a2eb 100755
@@ -14,10 +14,22 @@ compare_git_head_with () {
 	test_cmp current "$1"
 }
 
+a_utf8_locale=$(locale -a | sed -n '/\.[uU][tT][fF]-*8$/{
+	p
+	q
+}')
+
+if test -n "$a_utf8_locale"
+then
+	test_set_prereq UTF8
+else
+	say "UTF-8 locale not available, some tests are skipped"
+fi
+
 compare_svn_head_with () {
 	# extract just the log message and strip out committer info.
 	# don't use --limit here since svn 1.1.x doesn't have it,
-	LC_ALL=en_US.UTF-8 svn log `git svn info --url` | perl -w -e '
+	LC_ALL="$a_utf8_locale" svn log `git svn info --url` | perl -w -e '
 		use bytes;
 		$/ = ("-"x72) . "\n";
 		my @x = <STDIN>;

@@ -69,12 +81,6 @@ do
 	'
 done
 
-if locale -a |grep -q en_US.utf8; then
-	test_set_prereq UTF8
-else
-	say "UTF-8 locale not available, test skipped"
-fi
-
 test_expect_success UTF8 'ISO-8859-1 should match UTF-8 in svn' '
 	(
 		cd ISO8859-1 &&

new file mode 100755
index 0000000..33d47a5
@@ -0,0 +1,167 @@
+#!/usr/bin/env perl
+
+#
+# Copyright (c) 2011 Yann Droneaud <[email protected]>
+#
+# 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 http://www.gnu.org/licenses/ .
+#
+
+use strict;
+if ($] > 5.004) {
+    use warnings; # unless $] < 5.0004;
+}
+use POSIX;
+
+# according to manpage: setlocale can be used starting from perl 5.004
+# starting from May 1997.
+require 5.004;
+
+# it can also be tested with  perl -V:d_setlocale
+# which must return something like "d_setlocale='define';"
+
+my $default_locale = setlocale(LC_ALL);
+
+# try a locale and return its codeset if available
+sub locale_get_codeset
+{
+    my ($locale) = @_;
+    my $codeset;
+    my $ret;
+
+    $ret = setlocale(LC_ALL, $locale);
+    if (!defined($ret)) {
+	# print "can't set locale $locale\n";
+	return undef;
+    }
+
+    #
+    # I18N::Langinfo is not available everywhere
+    # use the trick from perldoc I18N::Langinfo
+    #
+    $codeset = eval {
+	require I18N::Langinfo;
+	I18N::Langinfo->import(qw(langinfo CODESET));
+	langinfo(CODESET()); # note the ()
+    };
+
+    if (defined($@) && $@) {
+	print STDERR "error while testing codeset:\n $@";
+	return undef;
+    }
+
+    # restore locale
+    setlocale(LC_ALL, $default_locale);
+
+    return $codeset;
+}
+
+# check that given codeset match UTF-8
+sub codeset_check
+{
+    my ($codeset) = @_;
+
+    if (defined($codeset) && $codeset =~ /^UTF[_-]?8$/i) {
+	return 1;
+    }
+
+    return 0;
+}
+
+# try all those locales
+# require en_US with UTF-8
+my @locales = ( "en_US.UTF-8",
+		"en_US.utf8",
+		"en_US.UTF8",
+		"en_US.utf-8",
+		"en_US.UTF_8",
+		"en_US.utf_8",
+		"en_US" );
+
+my $locale;
+
+my $codeset;
+
+#
+# Check locale from within perl
+#
+foreach $locale (@locales) {
+
+    $codeset = locale_get_codeset($locale);
+
+    if (codeset_check($codeset)) {
+	print $locale, "\n";
+	exit 0;
+    }
+}
+
+#
+# if 'locale' command is available, test 'locale charmap'
+#
+foreach $locale (@locales) {
+
+    $codeset = `LC_ALL=$locale locale charmap 2>/dev/null`;
+
+    # if any error, skip
+    if ($!) {
+	last;
+    }
+
+    if (codeset_check($codeset)) {
+	print $locale, "\n";
+	exit 0;
+    }
+}
+
+#
+# try to execute "locale -a" command
+# this command is not always available and
+# output format is not normalized
+#
+use IPC::Open3;
+use File::Spec;
+
+open(NULLR, "<", File::Spec->devnull) || die "Can't open devnull: $!";
+open(NULLW, ">", File::Spec->devnull) || die "Can't open devnull: $!";
+
+my $pid = open3("<&NULLR", \*LOCALES, ">&NULLW" , "locale", "-a") || die "Can't launch locale -a: $!";
+
+while(<LOCALES>) {
+     chomp;
+     if (/(en_US\.([\w-]+))/i) {
+	 if (codeset_check($2)) {
+	     $locale = $1;
+	     last;
+	 }
+     }
+}
+
+waitpid($pid, 0);
+
+my $retcode = $?;
+
+close(LOCALES);
+
+if ($retcode == 0) {
+    if (defined $locale) {
+	print "$locale\n";
+	exit 0;
+    }
+}
+
+#
+# Nothing available,
+# at last, return an error
+#
+
+exit 1;

index cb1ca97..3e92360 100644
@@ -1066,6 +1066,20 @@ case $(uname -s) in
 	;;
 esac
 
+# check UTF-8 locale availability
+test_utf8 () {
+    if test_have_prereq PERL ; then
+	# output an en_US.UTF-8 locale compatible name
+	GIT_LC_UTF8=`$PERL_PATH $GIT_BUILD_DIR/t/lib-locale.pl`
+    fi
+    if test -z "$GIT_LC_UTF8" ; then
+	return 1
+    else
+	test_set_prereq UTF8
+	return 0
+    fi
+}
+
 test -z "$NO_PERL" && test_set_prereq PERL
 test -z "$NO_PYTHON" && test_set_prereq PYTHON
 

index b041516..fcdffef 100755
@@ -4,20 +4,14 @@
 #
 
 test_description='git svn basic tests'
-GIT_SVN_LC_ALL=${LC_ALL:-$LANG}
 
 . ./lib-git-svn.sh
 
 say 'define NO_SVN_TESTS to skip git svn tests'
 
-case "$GIT_SVN_LC_ALL" in
-*.UTF-8)
-	test_set_prereq UTF8
-	;;
-*)
-	say "# UTF-8 locale not set, some tests skipped ($GIT_SVN_LC_ALL)"
-	;;
-esac
+if ! test_utf8 ; then
+	say "# UTF-8 locale not set, some tests skipped"
+fi
 
 test_expect_success \
     'initialize git svn' '

@@ -172,15 +166,12 @@ test_expect_success "$name" '
 	test ! -h "$SVN_TREE"/exec-2.sh &&
 	test_cmp help "$SVN_TREE"/exec-2.sh'
 
-name="commit with UTF-8 message: locale: $GIT_SVN_LC_ALL"
-LC_ALL="$GIT_SVN_LC_ALL"
-export LC_ALL
+name="commit with UTF-8 message: locale: $GIT_LC_UTF8"
 test_expect_success UTF8 "$name" "
-	echo '# hello' >> exec-2.sh &&
-	git update-index exec-2.sh &&
-	git commit -m 'éï∏' &&
-	git svn set-tree HEAD"
-unset LC_ALL
+	LC_ALL=$GIT_LC_UTF8 echo '# hello' >> exec-2.sh &&
+	LC_ALL=$GIT_LC_UTF8 git update-index exec-2.sh &&
+	LC_ALL=$GIT_LC_UTF8 git commit -m 'éï∏' &&
+	LC_ALL=$GIT_LC_UTF8 git svn set-tree HEAD"
 
 name='test fetch functionality (svn => git) with alternate GIT_SVN_ID'
 GIT_SVN_ID=alt

index 8cfdfe7..f3bbde4 100755
@@ -14,22 +14,15 @@ compare_git_head_with () {
 	test_cmp current "$1"
 }
 
-a_utf8_locale=$(locale -a | sed -n '/\.[uU][tT][fF]-*8$/{
-	p
-	q
-}')
-
-if test -n "$a_utf8_locale"
-then
-	test_set_prereq UTF8
-else
+if ! test_utf8 ; then
 	say "# UTF-8 locale not available, some tests are skipped"
 fi
 
 compare_svn_head_with () {
 	# extract just the log message and strip out committer info.
 	# don't use --limit here since svn 1.1.x doesn't have it,
-	LC_ALL="$a_utf8_locale" svn log `git svn info --url` | perl -w -e '
+	LC_ALL=$GIT_LC_UTF8 svn log `git svn info --url` | \
+	    LC_ALL=$GIT_LC_UTF8 perl -w -e '
 		use bytes;
 		$/ = ("-"x72) . "\n";
 		my @x = <STDIN>;

index f3bbde4..6dda569 100755
@@ -22,7 +22,7 @@ compare_svn_head_with () {
 	# extract just the log message and strip out committer info.
 	# don't use --limit here since svn 1.1.x doesn't have it,
 	LC_ALL=$GIT_LC_UTF8 svn log `git svn info --url` | \
-	    LC_ALL=$GIT_LC_UTF8 perl -w -e '
+	    LC_ALL=$GIT_LC_UTF8 $PERL_PATH -w -e '
 		use bytes;
 		$/ = ("-"x72) . "\n";
 		my @x = <STDIN>;