| 1 | /* Return number of characters in multibyte representation for current |
|---|
| 2 | character set. |
|---|
| 3 | Copyright (C) 1996-2022 Free Software Foundation, Inc. |
|---|
| 4 | This file is part of the GNU C Library. |
|---|
| 5 | |
|---|
| 6 | The GNU C Library is free software; you can redistribute it and/or |
|---|
| 7 | modify it under the terms of the GNU Lesser General Public |
|---|
| 8 | License as published by the Free Software Foundation; either |
|---|
| 9 | version 2.1 of the License, or (at your option) any later version. |
|---|
| 10 | |
|---|
| 11 | The GNU C Library is distributed in the hope that it will be useful, |
|---|
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
|---|
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
|---|
| 14 | Lesser General Public License for more details. |
|---|
| 15 | |
|---|
| 16 | You should have received a copy of the GNU Lesser General Public |
|---|
| 17 | License along with the GNU C Library; if not, see |
|---|
| 18 | <https://www.gnu.org/licenses/>. */ |
|---|
| 19 | |
|---|
| 20 | #include <langinfo.h> |
|---|
| 21 | #include <locale.h> |
|---|
| 22 | #include <stdlib.h> |
|---|
| 23 | #include "localeinfo.h" |
|---|
| 24 | |
|---|
| 25 | |
|---|
| 26 | /* This is a gross hack to get broken programs running. |
|---|
| 27 | |
|---|
| 28 | ISO C provides no mean to find out how many bytes the wide |
|---|
| 29 | character representation really uses. But it defines MB_CUR_LEN to |
|---|
| 30 | return the information for the multi-byte character representation. |
|---|
| 31 | Many programmers don't know the difference between the two and |
|---|
| 32 | think this means the same. But assuming all characters have a size |
|---|
| 33 | of MB_CUR_LEN after they have been processed by `mbrtowc' is wrong. |
|---|
| 34 | Instead the maximum number of characters used for the conversion is |
|---|
| 35 | MB_CUR_LEN. |
|---|
| 36 | |
|---|
| 37 | It is known that some Motif applications have this problem. To |
|---|
| 38 | cure this one has to make sure the glibc uses the function in this |
|---|
| 39 | file instead of the one in locale/mb_cur_max.c. This can either be |
|---|
| 40 | done by linking with this file or by using the LD_PRELOAD feature |
|---|
| 41 | of the dynamic linker. */ |
|---|
| 42 | size_t |
|---|
| 43 | __ctype_get_mb_cur_max (void) |
|---|
| 44 | { |
|---|
| 45 | union locale_data_value u; |
|---|
| 46 | |
|---|
| 47 | u.string = nl_langinfo (item: _NL_CTYPE_MB_CUR_MAX); |
|---|
| 48 | return ((size_t []) { 1, 1, 1, 2, 2, 3, 4 })[u.word]; |
|---|
| 49 | } |
|---|
| 50 | |
|---|
