1 /* Test for initial conversion state. 2 Copyright (C) 2008-2012 Free Software Foundation, Inc. 3 Written by Bruno Haible <bruno (at) 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 62
