| 1 | /* |
| 2 | * Copyright (C) 2001 Edmund Grimley Evans <edmundo@rano.org> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation; either version 2 of the License, or |
| 7 | * (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License along |
| 15 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 16 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 17 | */ |
| 18 | |
| 19 | #include <stdlib.h> |
| 20 | |
| 21 | /* |
| 22 | * These functions are like the C library's mbtowc() and wctomb(), |
| 23 | * but instead of depending on the locale they always work in UTF-8, |
| 24 | * and they use int instead of wchar_t. |
| 25 | */ |
| 26 | |
| 27 | int utf8_mbtowc(int *pwc, const char *s, size_t n); |
| 28 | int utf8_wctomb(char *s, int wc); |
| 29 | |
| 30 | /* |
| 31 | * This is an object-oriented version of mbtowc() and wctomb(). |
| 32 | * The caller first uses charset_find() to get a pointer to struct |
| 33 | * charset, then uses the mbtowc() and wctomb() methods on it. |
| 34 | * The function charset_max() gives the maximum length of a |
| 35 | * multibyte character in that encoding. |
| 36 | * This API is only appropriate for stateless encodings like UTF-8 |
| 37 | * or ISO-8859-3, but I have no intention of implementing anything |
| 38 | * other than UTF-8 and 8-bit encodings. |
| 39 | * |
| 40 | * MINOR BUG: If there is no memory charset_find() may return 0 and |
| 41 | * there is no way to distinguish this case from an unknown encoding. |
| 42 | */ |
| 43 | |
| 44 | struct charset; |
| 45 | |
| 46 | struct charset *charset_find(const char *code); |
| 47 | |
| 48 | int charset_mbtowc(struct charset *charset, int *pwc, const char *s, size_t n); |
| 49 | int charset_wctomb(struct charset *charset, char *s, int wc); |
| 50 | int charset_max(struct charset *charset); |
| 51 | |
| 52 | /* |
| 53 | * Function to convert a buffer from one encoding to another. |
| 54 | * Invalid bytes are replaced by '#', and characters that are |
| 55 | * not available in the target encoding are replaced by '?'. |
| 56 | * Each of TO and TOLEN may be zero if the result is not wanted. |
| 57 | * The input or output may contain null bytes, but the output |
| 58 | * buffer is also null-terminated, so it is all right to |
| 59 | * use charset_convert(fromcode, tocode, s, strlen(s), &t, 0). |
| 60 | * |
| 61 | * Return value: |
| 62 | * |
| 63 | * -2 : memory allocation failed |
| 64 | * -1 : unknown encoding |
| 65 | * 0 : data was converted exactly |
| 66 | * 1 : valid data was converted approximately (using '?') |
| 67 | * 2 : input was invalid (but still converted, using '#') |
| 68 | */ |
| 69 | |
| 70 | int charset_convert(const char *fromcode, const char *tocode, |
| 71 | const char *from, size_t fromlen, |
| 72 | char **to, size_t *tolen); |