Fix phpGH-11338: SplFileInfo empty getBasename with more than on slash

Regressed in 13e4ce3.

Author: nielsdos

ext/spl/spl_directory.c

@@ -432,7 +432,9 @@ static void spl_filesystem_info_set_filename(spl_filesystem_object *intern, zend
 
 	path_len = ZSTR_LEN(path);
 	if (path_len > 1 && IS_SLASH_AT(ZSTR_VAL(path), path_len-1)) {
-		path_len--;
+		do {
+			path_len--;
+		} while (path_len > 1 && IS_SLASH_AT(ZSTR_VAL(path), path_len - 1));
 		intern->file_name = zend_string_init(ZSTR_VAL(path), path_len, 0);
 	} else {
 		intern->file_name = zend_string_copy(path);

ext/spl/tests/gh11338.phpt

@@ -0,0 +1,47 @@
+--TEST--
+GH-11338 (SplFileInfo empty getBasename with more than on slash)
+--FILE--
+<?php
+
+function test($path) {
+    echo "Testing: '$path'\n";
+    $file = new \SplFileInfo($path);
+    var_dump($file->getBasename());
+    var_dump($file->getFilename());
+}
+
+test('/dir/anotherdir/basedir//');
+test('/dir/anotherdir/basedir/');
+test('/dir/anotherdir/basedir');
+test('/dir/anotherdir//basedir');
+test('///');
+test('//');
+test('/');
+test('');
+
+?>
+--EXPECT--
+Testing: '/dir/anotherdir/basedir//'
+string(7) "basedir"
+string(7) "basedir"
+Testing: '/dir/anotherdir/basedir/'
+string(7) "basedir"
+string(7) "basedir"
+Testing: '/dir/anotherdir/basedir'
+string(7) "basedir"
+string(7) "basedir"
+Testing: '/dir/anotherdir//basedir'
+string(7) "basedir"
+string(7) "basedir"
+Testing: '///'
+string(0) ""
+string(1) "/"
+Testing: '//'
+string(0) ""
+string(1) "/"
+Testing: '/'
+string(0) ""
+string(1) "/"
+Testing: ''
+string(0) ""
+string(0) ""