/* Test of c32tolower() function.
   Copyright (C) 2020-2026 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/>.  */

#include <config.h>

#include <uchar.h>

#include "signature.h"
SIGNATURE_CHECK (c32tolower, wint_t, (wint_t));

#include <locale.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>

#include "macros.h"

/* Representation of a multibyte character.  */
#define MBCHAR_BUF_SIZE 6
struct multibyte
{
  size_t nbytes;             /* number of bytes of current character, > 0 */
  char buf[MBCHAR_BUF_SIZE]; /* room for the bytes */
};

/* Returns the value of c32tolower for the multibyte character s[0..n-1],
   as a multibyte character.  */
static struct multibyte
for_character (const char *s, size_t n)
{
  mbstate_t state;
  char32_t wc;
  size_t ret;
  struct multibyte result;

  memset (&state, '\0', sizeof (mbstate_t));
  wc = (char32_t) 0xBADFACE;
  ret = mbrtoc32 (&wc, s, n, &state);
  ASSERT (ret == n);

  wc = c32tolower (wc);
  ASSERT (wc != WEOF);

  memset (&state, '\0', sizeof (mbstate_t));
  ret = c32rtomb (result.buf, wc, &state);
  ASSERT (ret != 0);
  if (ret == (size_t)(-1))
    /* wc cannot be converted back to multibyte.  */
    result.nbytes = 0;
  else
    {
      ASSERT (ret <= MBCHAR_BUF_SIZE);
      result.nbytes = ret;
    }
  return result;
}

int
main (int argc, char *argv[])
{
  wint_t wc;
  struct multibyte mb;
  char buf[4];

  /* configure should already have checked that the locale is supported.  */
  if (setlocale (LC_ALL, "") == NULL)
    return 1;

  /* Test WEOF.  */
  wc = c32tolower (WEOF);
  ASSERT (wc == WEOF);

  /* Test single-byte characters.
     POSIX specifies in
       <https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap07.html>
     that
       - in all locales, the uppercase characters include the A ... Z
         characters, and the corresponding characters a ... z (if not in a
         Turkish locale) are lowercase,
       - in the "POSIX" locale (which is usually the same as the "C" locale),
         the uppercase characters include only the ASCII A ... Z characters,
         and the corresponding characters a ... z are lowercase.
   */
#if defined __NetBSD__
  /* towlower is broken in the zh_CN.GB18030 locale on NetBSD 9.0.
     See <https://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=57339>.  */
  if (!(argc > 1 && argv[1][0] == '4'))
#endif
  for (int c = 0; c < 0x100; c++)
    switch (c)
      {
      case '\t': case '\v': case '\f':
      case ' ': case '!': case '"': case '#': case '%':
      case '&': case '\'': case '(': case ')': case '*':
      case '+': case ',': case '-': case '.': case '/':
      case '0': case '1': case '2': case '3': case '4':
      case '5': case '6': case '7': case '8': case '9':
      case ':': case ';': case '<': case '=': case '>':
      case '?':
      case 'A': case 'B': case 'C': case 'D': case 'E':
      case 'F': case 'G': case 'H': case 'I': case 'J':
      case 'K': case 'L': case 'M': case 'N': case 'O':
      case 'P': case 'Q': case 'R': case 'S': case 'T':
      case 'U': case 'V': case 'W': case 'X': case 'Y':
      case 'Z':
      case '[': case '\\': case ']': case '^': case '_':
      case 'a': case 'b': case 'c': case 'd': case 'e':
      case 'f': case 'g': case 'h': case 'i': case 'j':
      case 'k': case 'l': case 'm': case 'n': case 'o':
      case 'p': case 'q': case 'r': case 's': case 't':
      case 'u': case 'v': case 'w': case 'x': case 'y':
      case 'z': case '{': case '|': case '}': case '~':
        /* c is in the ISO C "basic character set".  */
        buf[0] = (unsigned char) c;
        mb = for_character (buf, 1);
        switch (c)
          {
          case 'A': case 'B': case 'C': case 'D': case 'E':
          case 'F': case 'G': case 'H': case 'I': case 'J':
          case 'K': case 'L': case 'M': case 'N': case 'O':
          case 'P': case 'Q': case 'R': case 'S': case 'T':
          case 'U': case 'V': case 'W': case 'X': case 'Y':
          case 'Z':
            ASSERT (mb.nbytes == 1);
            ASSERT ((unsigned char) mb.buf[0] == (unsigned char) c - 'A' + 'a');
            break;
          default:
            ASSERT (mb.nbytes == 1);
            ASSERT ((unsigned char) mb.buf[0] == c);
            break;
          }
        break;
      }

  if (argc > 1)
    switch (argv[1][0])
      {
      case '0':
        /* C locale; tested above.  */
        return test_exit_status;

      case '1':
        /* Locale encoding is ISO-8859-1 or ISO-8859-15.  */
        {
          /* U+00B2 SUPERSCRIPT TWO */
          mb = for_character ("\262", 1);
          ASSERT (mb.nbytes == 1);
          ASSERT (memeq (mb.buf, "\262", 1));
          /* U+00B5 MICRO SIGN */
          mb = for_character ("\265", 1);
          ASSERT (mb.nbytes == 1);
          ASSERT (memeq (mb.buf, "\265", 1));
          /* U+00C9 LATIN CAPITAL LETTER E WITH ACUTE */
          mb = for_character ("\311", 1);
          ASSERT (mb.nbytes == 1);
          ASSERT (memeq (mb.buf, "\351", 1));
          /* U+00DF LATIN SMALL LETTER SHARP S */
          mb = for_character ("\337", 1);
          ASSERT (mb.nbytes == 1);
          ASSERT (memeq (mb.buf, "\337", 1));
          /* U+00E9 LATIN SMALL LETTER E WITH ACUTE */
          mb = for_character ("\351", 1);
          ASSERT (mb.nbytes == 1);
          ASSERT (memeq (mb.buf, "\351", 1));
          /* U+00FF LATIN SMALL LETTER Y WITH DIAERESIS */
          mb = for_character ("\377", 1);
          ASSERT (mb.nbytes == 1);
          ASSERT (memeq (mb.buf, "\377", 1));
        }
        return test_exit_status;

      case '2':
        /* Locale encoding is EUC-JP.  */
        {
        #if !((defined __APPLE__ && defined __MACH__) || defined __DragonFly__)
          /* U+00C9 LATIN CAPITAL LETTER E WITH ACUTE */
          mb = for_character ("\217\252\261", 3);
          ASSERT (mb.nbytes == 3);
          ASSERT (memeq (mb.buf, "\217\253\261", 3));
        #endif
          /* U+00DF LATIN SMALL LETTER SHARP S */
          mb = for_character ("\217\251\316", 3);
          ASSERT (mb.nbytes == 3);
          ASSERT (memeq (mb.buf, "\217\251\316", 3));
          /* U+00E9 LATIN SMALL LETTER E WITH ACUTE */
          mb = for_character ("\217\253\261", 3);
          ASSERT (mb.nbytes == 3);
          ASSERT (memeq (mb.buf, "\217\253\261", 3));
          /* U+00FF LATIN SMALL LETTER Y WITH DIAERESIS */
          mb = for_character ("\217\253\363", 3);
          ASSERT (mb.nbytes == 3);
          ASSERT (memeq (mb.buf, "\217\253\363", 3));
        #if !((defined __APPLE__ && defined __MACH__) || defined __DragonFly__)
          /* U+0141 LATIN CAPITAL LETTER L WITH STROKE */
          mb = for_character ("\217\251\250", 3);
          ASSERT (mb.nbytes == 3);
          ASSERT (memeq (mb.buf, "\217\251\310", 3));
        #endif
          /* U+0142 LATIN SMALL LETTER L WITH STROKE */
          mb = for_character ("\217\251\310", 3);
          ASSERT (mb.nbytes == 3);
          ASSERT (memeq (mb.buf, "\217\251\310", 3));
        #if !defined __DragonFly__
          /* U+0429 CYRILLIC CAPITAL LETTER SHCHA */
          mb = for_character ("\247\273", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\247\353", 2));
        #endif
          /* U+0449 CYRILLIC SMALL LETTER SHCHA */
          mb = for_character ("\247\353", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\247\353", 2));
          /* U+3073 HIRAGANA LETTER BI */
          mb = for_character ("\244\323", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\244\323", 2));
        #if !defined __DragonFly__
          /* U+FF27 FULLWIDTH LATIN CAPITAL LETTER G */
          mb = for_character ("\243\307", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\243\347", 2));
        #endif
          /* U+FF47 FULLWIDTH LATIN SMALL LETTER G */
          mb = for_character ("\243\347", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\243\347", 2));
        }
        return test_exit_status;

      case '3':
        /* Locale encoding is UTF-8.  */
        {
          /* U+00B2 SUPERSCRIPT TWO */
          mb = for_character ("\302\262", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\302\262", 2));
          /* U+00B5 MICRO SIGN */
          mb = for_character ("\302\265", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\302\265", 2));
          /* U+00C9 LATIN CAPITAL LETTER E WITH ACUTE */
          mb = for_character ("\303\211", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\303\251", 2));
          /* U+00DF LATIN SMALL LETTER SHARP S */
          mb = for_character ("\303\237", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\303\237", 2));
          /* U+00E9 LATIN SMALL LETTER E WITH ACUTE */
          mb = for_character ("\303\251", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\303\251", 2));
          /* U+00FF LATIN SMALL LETTER Y WITH DIAERESIS */
          mb = for_character ("\303\277", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\303\277", 2));
          /* U+0141 LATIN CAPITAL LETTER L WITH STROKE */
          mb = for_character ("\305\201", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\305\202", 2));
          /* U+0142 LATIN SMALL LETTER L WITH STROKE */
          mb = for_character ("\305\202", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\305\202", 2));
          /* U+0429 CYRILLIC CAPITAL LETTER SHCHA */
          mb = for_character ("\320\251", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\321\211", 2));
          /* U+0449 CYRILLIC SMALL LETTER SHCHA */
          mb = for_character ("\321\211", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\321\211", 2));
          /* U+05D5 HEBREW LETTER VAV */
          mb = for_character ("\327\225", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\327\225", 2));
          /* U+3073 HIRAGANA LETTER BI */
          mb = for_character ("\343\201\263", 3);
          ASSERT (mb.nbytes == 3);
          ASSERT (memeq (mb.buf, "\343\201\263", 3));
          /* U+3162 HANGUL LETTER YI */
          mb = for_character ("\343\205\242", 3);
          ASSERT (mb.nbytes == 3);
          ASSERT (memeq (mb.buf, "\343\205\242", 3));
          /* U+FF27 FULLWIDTH LATIN CAPITAL LETTER G */
          mb = for_character ("\357\274\247", 3);
          ASSERT (mb.nbytes == 3);
          ASSERT (memeq (mb.buf, "\357\275\207", 3));
          /* U+FF47 FULLWIDTH LATIN SMALL LETTER G */
          mb = for_character ("\357\275\207", 3);
          ASSERT (mb.nbytes == 3);
          ASSERT (memeq (mb.buf, "\357\275\207", 3));
          /* U+FFDB HALFWIDTH HANGUL LETTER YI */
          mb = for_character ("\357\277\233", 3);
          ASSERT (mb.nbytes == 3);
          ASSERT (memeq (mb.buf, "\357\277\233", 3));
        #if !(defined __DragonFly__ || defined __sun)
          /* U+10419 DESERET CAPITAL LETTER EF */
          mb = for_character ("\360\220\220\231", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\360\220\221\201", 4));
        #endif
          /* U+10441 DESERET SMALL LETTER EF */
          mb = for_character ("\360\220\221\201", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\360\220\221\201", 4));
          /* U+E0041 TAG LATIN CAPITAL LETTER A */
          mb = for_character ("\363\240\201\201", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\363\240\201\201", 4));
          /* U+E0061 TAG LATIN SMALL LETTER A */
          mb = for_character ("\363\240\201\241", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\363\240\201\241", 4));
        }
        return test_exit_status;

      case '4':
        /* Locale encoding is GB18030.  */
        #if (defined __GLIBC__ && __GLIBC__ == 2 && __GLIBC_MINOR__ >= 13 && __GLIBC_MINOR__ <= 15) || (GL_CHAR32_T_IS_UNICODE && (defined __FreeBSD__ || defined __NetBSD__ || defined __sun))
        if (test_exit_status != EXIT_SUCCESS)
          return test_exit_status;
        fputs ("Skipping test: The GB18030 converter in this system's iconv is broken.\n", stderr);
        return 77;
        #endif
        {
          /* U+00B2 SUPERSCRIPT TWO */
          mb = for_character ("\201\060\205\065", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\201\060\205\065", 4));
          /* U+00B5 MICRO SIGN */
          mb = for_character ("\201\060\205\070", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\201\060\205\070", 4));
        #if !((defined __APPLE__ && defined __MACH__) || defined __FreeBSD__ || defined __DragonFly__ || defined __sun)
          /* U+00C9 LATIN CAPITAL LETTER E WITH ACUTE */
          mb = for_character ("\201\060\207\067", 4);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\250\246", 2));
        #endif
          /* U+00DF LATIN SMALL LETTER SHARP S */
          mb = for_character ("\201\060\211\070", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\201\060\211\070", 4));
          /* U+00E9 LATIN SMALL LETTER E WITH ACUTE */
          mb = for_character ("\250\246", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\250\246", 2));
          /* U+00FF LATIN SMALL LETTER Y WITH DIAERESIS */
          mb = for_character ("\201\060\213\067", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\201\060\213\067", 4));
        #if !((defined __APPLE__ && defined __MACH__) || defined __FreeBSD__ || defined __DragonFly__ || defined __sun)
          /* U+0141 LATIN CAPITAL LETTER L WITH STROKE */
          mb = for_character ("\201\060\221\071", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\201\060\222\060", 4));
        #endif
          /* U+0142 LATIN SMALL LETTER L WITH STROKE */
          mb = for_character ("\201\060\222\060", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\201\060\222\060", 4));
        #if !((defined __APPLE__ && defined __MACH__) || defined __FreeBSD__ || defined __DragonFly__)
          /* U+0429 CYRILLIC CAPITAL LETTER SHCHA */
          mb = for_character ("\247\273", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\247\353", 2));
        #endif
          /* U+0449 CYRILLIC SMALL LETTER SHCHA */
          mb = for_character ("\247\353", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\247\353", 2));
          /* U+05D5 HEBREW LETTER VAV */
          mb = for_character ("\201\060\371\067", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\201\060\371\067", 4));
          /* U+3073 HIRAGANA LETTER BI */
          mb = for_character ("\244\323", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\244\323", 2));
          /* U+3162 HANGUL LETTER YI */
          mb = for_character ("\201\071\256\062", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\201\071\256\062", 4));
        #if !defined __DragonFly__
          /* U+FF27 FULLWIDTH LATIN CAPITAL LETTER G */
          mb = for_character ("\243\307", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\243\347", 2));
        #endif
          /* U+FF47 FULLWIDTH LATIN SMALL LETTER G */
          mb = for_character ("\243\347", 2);
          ASSERT (mb.nbytes == 2);
          ASSERT (memeq (mb.buf, "\243\347", 2));
          /* U+FFDB HALFWIDTH HANGUL LETTER YI */
          mb = for_character ("\204\061\241\071", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\204\061\241\071", 4));
        #if !((defined __APPLE__ && defined __MACH__) || defined __FreeBSD__ || defined __DragonFly__ || defined __NetBSD__ || defined __sun)
          /* U+10419 DESERET CAPITAL LETTER EF */
          mb = for_character ("\220\060\351\071", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\220\060\355\071", 4));
        #endif
          /* U+10441 DESERET SMALL LETTER EF */
          mb = for_character ("\220\060\355\071", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\220\060\355\071", 4));
          /* U+E0041 TAG LATIN CAPITAL LETTER A */
          mb = for_character ("\323\066\234\063", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\323\066\234\063", 4));
          /* U+E0061 TAG LATIN SMALL LETTER A */
          mb = for_character ("\323\066\237\065", 4);
          ASSERT (mb.nbytes == 4);
          ASSERT (memeq (mb.buf, "\323\066\237\065", 4));
        }
        return test_exit_status;

      }

  return 1;
}
