Ying Wang | 0543663 | 2013-04-05 16:01:00 -0700 | [diff] [blame] | 1 | /* Test for initial conversion state. |
| 2 | Copyright (C) 2008-2012 Free Software Foundation, Inc. |
| 3 | Written by Bruno Haible <bruno@clisp.org>, 2008. |
| 4 | |
| 5 | This program is free software: you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by |
| 7 | the Free Software Foundation; either version 3 of the License, or |
| 8 | (at your option) any later version. |
| 9 | |
| 10 | This program is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | GNU General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU General Public License |
| 16 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 17 | |
| 18 | #include <config.h> |
| 19 | |
| 20 | /* Specification. */ |
| 21 | #include <wchar.h> |
| 22 | |
| 23 | #include "verify.h" |
| 24 | |
| 25 | #if (defined _WIN32 || defined __WIN32__) && !defined __CYGWIN__ |
| 26 | |
| 27 | /* On native Windows, 'mbstate_t' is defined as 'int'. */ |
| 28 | |
| 29 | int |
| 30 | mbsinit (const mbstate_t *ps) |
| 31 | { |
| 32 | return ps == NULL || *ps == 0; |
| 33 | } |
| 34 | |
| 35 | #else |
| 36 | |
| 37 | /* Platforms that lack mbsinit() also lack mbrlen(), mbrtowc(), mbsrtowcs() |
| 38 | and wcrtomb(), wcsrtombs(). |
| 39 | We assume that |
| 40 | - sizeof (mbstate_t) >= 4, |
| 41 | - only stateless encodings are supported (such as UTF-8 and EUC-JP, but |
| 42 | not ISO-2022 variants), |
| 43 | - for each encoding, the number of bytes for a wide character is <= 4. |
| 44 | (This maximum is attained for UTF-8, GB18030, EUC-TW.) |
| 45 | We define the meaning of mbstate_t as follows: |
| 46 | - In mb -> wc direction, mbstate_t's first byte contains the number of |
| 47 | buffered bytes (in the range 0..3), followed by up to 3 buffered bytes. |
| 48 | - In wc -> mb direction, mbstate_t contains no information. In other |
| 49 | words, it is always in the initial state. */ |
| 50 | |
| 51 | verify (sizeof (mbstate_t) >= 4); |
| 52 | |
| 53 | int |
| 54 | mbsinit (const mbstate_t *ps) |
| 55 | { |
| 56 | const char *pstate = (const char *)ps; |
| 57 | |
| 58 | return pstate == NULL || pstate[0] == 0; |
| 59 | } |
| 60 | |
| 61 | #endif |