1 files changed, 157 insertions, 0 deletions
diff --git a/lib/mbrtowc.c b/lib/mbrtowc.c
new file mode 100644
index 0000000..c1a689a
--- /dev/null
+++ b/lib/mbrtowc.c
@@ -0,0 +1,157 @@
+/* Convert multibyte character to wide character.
+   Copyright (C) 1999-2002, 2005-2023 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2008.
+
+   This file is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Lesser General Public License as
+   published by the Free Software Foundation; either version 2.1 of the
+   License, or (at your option) any later version.
+
+   This file 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 Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include <wchar.h>
+
+#if GNULIB_defined_mbstate_t
+/* Implement mbrtowc() on top of mbtowc() for the non-UTF-8 locales
+   and directly for the UTF-8 locales.  */
+
+# include <errno.h>
+# include <stdint.h>
+# include <stdlib.h>
+
+# if defined _WIN32 && !defined __CYGWIN__
+
+#  define WIN32_LEAN_AND_MEAN  /* avoid including junk */
+#  include <windows.h>
+
+# elif HAVE_PTHREAD_API
+
+#  include <pthread.h>
+#  if HAVE_THREADS_H && HAVE_WEAK_SYMBOLS
+#   include <threads.h>
+#   pragma weak thrd_exit
+#   define c11_threads_in_use() (thrd_exit != NULL)
+#  else
+#   define c11_threads_in_use() 0
+#  endif
+
+# elif HAVE_THREADS_H
+
+#  include <threads.h>
+
+# endif
+
+# include "attribute.h"
+# include "lc-charset-dispatch.h"
+# include "mbtowc-lock.h"
+
+static_assert (sizeof (mbstate_t) >= 4);
+static char internal_state[4];
+
+size_t
+mbrtowc (wchar_t *pwc, const char *s, size_t n, mbstate_t *ps)
+{
+# define FITS_IN_CHAR_TYPE(wc)  ((wc) <= WCHAR_MAX)
+# include "mbrtowc-impl.h"
+}
+
+#else
+/* Override the system's mbrtowc() function.  */
+
+# if MBRTOWC_IN_C_LOCALE_MAYBE_EILSEQ
+#  include "hard-locale.h"
+#  include <locale.h>
+# endif
+
+# undef mbrtowc
+
+size_t
+rpl_mbrtowc (wchar_t *pwc, const char *s, size_t n, mbstate_t *ps)
+{
+  size_t ret;
+  wchar_t wc;
+
+# if MBRTOWC_NULL_ARG2_BUG || MBRTOWC_RETVAL_BUG || MBRTOWC_EMPTY_INPUT_BUG
+  if (s == NULL)
+    {
+      pwc = NULL;
+      s = "";
+      n = 1;
+    }
+# endif
+
+# if MBRTOWC_EMPTY_INPUT_BUG
+  if (n == 0)
+    return (size_t) -2;
+# endif
+
+  if (! pwc)
+    pwc = &wc;
+
+# if MBRTOWC_RETVAL_BUG
+  {
+    static mbstate_t internal_state;
+
+    /* Override mbrtowc's internal state.  We cannot call mbsinit() on the
+       hidden internal state, but we can call it on our variable.  */
+    if (ps == NULL)
+      ps = &internal_state;
+
+    if (!mbsinit (ps))
+      {
+        /* Parse the rest of the multibyte character byte for byte.  */
+        size_t count = 0;
+        for (; n > 0; s++, n--)
+          {
+            ret = mbrtowc (&wc, s, 1, ps);
+
+            if (ret == (size_t)(-1))
+              return (size_t)(-1);
+            count++;
+            if (ret != (size_t)(-2))
+              {
+                /* The multibyte character has been completed.  */
+                *pwc = wc;
+                return (wc == 0 ? 0 : count);
+              }
+          }
+        return (size_t)(-2);
+      }
+  }
+# endif
+
+# if MBRTOWC_STORES_INCOMPLETE_BUG
+  ret = mbrtowc (&wc, s, n, ps);
+  if (ret < (size_t) -2 && pwc != NULL)
+    *pwc = wc;
+# else
+  ret = mbrtowc (pwc, s, n, ps);
+# endif
+
+# if MBRTOWC_NUL_RETVAL_BUG
+  if (ret < (size_t) -2 && !*pwc)
+    return 0;
+# endif
+
+# if MBRTOWC_IN_C_LOCALE_MAYBE_EILSEQ
+  if ((size_t) -2 <= ret && n != 0 && ! hard_locale (LC_CTYPE))
+    {
+      unsigned char uc = *s;
+      *pwc = uc;
+      return 1;
+    }
+# endif
+
+  return ret;
+}
+
+#endif