--- /dev/null
+/* Test of conversion of multibyte character to 32-bit wide character.
+ Copyright (C) 2023 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 <https://www.gnu.org/licenses/>. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2023. */
+
+#include <config.h>
+
+#include <uchar.h>
+
+#include <locale.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <uchar.h>
+#include <wchar.h>
+
+#include "macros.h"
+
+int
+main (int argc, char *argv[])
+{
+ /* The only locales in which mbrtoc32 may map a multibyte character to a
+ sequence of two or more Unicode characters are those with BIG5-HKSCS
+ encoding. See
+ <https://lists.gnu.org/archive/html/bug-gnulib/2023-06/msg00134.html>
+ <https://lists.gnu.org/archive/html/bug-gnulib/2023-07/msg00014.html> */
+ if (setlocale (LC_ALL, "zh_HK.BIG5-HKSCS") == NULL)
+ {
+ fprintf (stderr, "Skipping test: found no locale with BIG5-HKSCS encoding.\n");
+ return 77;
+ }
+
+ /* The problematic BIG5-HKSCS characters are:
+
+ input maps to name
+ ----- ------- ----
+ 0x88 0x62 U+00CA U+0304 LATIN CAPITAL LETTER E WITH CIRCUMFLEX AND MACRON
+ 0x88 0x64 U+00CA U+030C LATIN CAPITAL LETTER E WITH CIRCUMFLEX AND CARON
+ 0x88 0xA3 U+00EA U+0304 LATIN SMALL LETTER E WITH CIRCUMFLEX AND MACRON
+ 0x88 0xA5 U+00EA U+030C LATIN SMALL LETTER E WITH CIRCUMFLEX AND CARON
+
+ Test one of them.
+ See <https://sourceware.org/bugzilla/show_bug.cgi?id=30611>. */
+ mbstate_t state;
+ memset (&state, '\0', sizeof (mbstate_t));
+ char32_t c32 = (char32_t) 0xBADFACE;
+ size_t ret = mbrtoc32 (&c32, "\210\142", 2, &state);
+ /* It is OK if this conversion fails. */
+ if (ret != (size_t)(-1))
+ {
+ /* mbrtoc32 being regular, means that STATE is in the initial state. */
+ ASSERT (mbsinit (&state));
+ ret = mbrtoc32 (&c32, "", 0, &state);
+ /* mbrtoc32 being regular, means that it returns (size_t)(-2), not
+ (size_t)(-3), here. */
+ ASSERT (ret == (size_t)(-2));
+ ret = mbrtoc32 (&c32, "", 1, &state);
+ /* mbrtoc32 being regular, means that it returns the null 32-bit wide
+ character, here, not any remnant from the previous multibyte
+ character. */
+ ASSERT (ret == 0);
+ ASSERT (c32 == 0);
+ }
+
+ return 0;
+}