cosmopolitan/libc/str/setlocale.c

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│ vi: set et ft=c ts=2 sts=2 sw=2 fenc=utf-8                               :vi │
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2021 Justine Alexandra Roberts Tunney                              │
│                                                                              │
│ Permission to use, copy, modify, and/or distribute this software for         │
│ any purpose with or without fee is hereby granted, provided that the         │
│ above copyright notice and this permission notice appear in all copies.      │
│                                                                              │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
│ PERFORMANCE OF THIS SOFTWARE.                                                │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/intrin/safemacros.internal.h"
#include "libc/intrin/strace.internal.h"
#include "libc/str/locale.h"
#include "libc/str/str.h"

/**
 * Sets program locale.
 *
 * Cosmopolitan only supports the C or POSIX locale with UTF-8.
 */
char *setlocale(int category, const char *locale) {
  char *res;
  if (!locale || (*locale == '\0')) {
    res = "C";
  } else if (!strcmp(locale, "C") ||        //
             !strcmp(locale, "POSIX") ||    //
             !strcmp(locale, "C.UTF-8") ||  //
             !strcmp(locale, "en_US.UTF-8")) {
    res = (char *)locale;
  } else {
    res = NULL;
  }
  STRACE("setlocale(%d, %#s) → %s", category, locale, res);
  return res;
}