| /* Copyright (C) 1991-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library 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. |
| |
| The GNU C Library 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 the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <stdlib.h> |
| #include <string.h> |
| #include <wchar.h> |
| #include <gconv.h> |
| #include <wcsmbs/wcsmbsload.h> |
| |
| |
| /* Internal state. */ |
| static mbstate_t state; |
| |
| /* Return the length of the multibyte character (if there is one) |
| at S which is no longer than N characters. |
| The ISO C standard says that the `mblen' function must not change |
| the state of the `mbtowc' function. */ |
| int |
| mblen (const char *s, size_t n) |
| { |
| int result; |
| |
| /* If S is NULL the function has to return null or not null |
| depending on the encoding having a state depending encoding or |
| not. */ |
| if (s == NULL) |
| { |
| const struct gconv_fcts *fcts; |
| |
| /* Get the conversion functions. */ |
| fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE)); |
| |
| /* Reset the state. */ |
| memset (&state, '\0', sizeof state); |
| |
| result = fcts->towc->__stateful; |
| } |
| else if (*s == '\0') |
| /* According to the ISO C 89 standard this is the expected behaviour. */ |
| result = 0; |
| else |
| { |
| memset (&state, '\0', sizeof state); |
| |
| result = __mbrtowc (NULL, s, n, &state); |
| |
| /* The `mbrtowc' functions tell us more than we need. Fold the -1 |
| and -2 result into -1. */ |
| if (result < 0) |
| result = -1; |
| } |
| |
| return result; |
| } |