diff options
Diffstat (limited to 'lib/unistr/u8-prev.c')
-rw-r--r-- | lib/unistr/u8-prev.c | 93 |
1 files changed, 0 insertions, 93 deletions
diff --git a/lib/unistr/u8-prev.c b/lib/unistr/u8-prev.c deleted file mode 100644 index b609acf73..000000000 --- a/lib/unistr/u8-prev.c +++ /dev/null @@ -1,93 +0,0 @@ -/* Iterate over previous character in UTF-8 string. - Copyright (C) 2002, 2006-2007, 2009-2016 Free Software Foundation, Inc. - Written by Bruno Haible <bruno@clisp.org>, 2002. - - This program 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 3 of the License, or - (at your option) any later version. - - This program 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 this program. If not, see <http://www.gnu.org/licenses/>. */ - -#include <config.h> - -/* Specification. */ -#include "unistr.h" - -const uint8_t * -u8_prev (ucs4_t *puc, const uint8_t *s, const uint8_t *start) -{ - /* Keep in sync with unistr.h and u8-mbtouc-aux.c. */ - if (s != start) - { - uint8_t c_1 = s[-1]; - - if (c_1 < 0x80) - { - *puc = c_1; - return s - 1; - } -#if CONFIG_UNICODE_SAFETY - if ((c_1 ^ 0x80) < 0x40) -#endif - if (s - 1 != start) - { - uint8_t c_2 = s[-2]; - - if (c_2 >= 0xc2 && c_2 < 0xe0) - { - *puc = ((unsigned int) (c_2 & 0x1f) << 6) - | (unsigned int) (c_1 ^ 0x80); - return s - 2; - } -#if CONFIG_UNICODE_SAFETY - if ((c_2 ^ 0x80) < 0x40) -#endif - if (s - 2 != start) - { - uint8_t c_3 = s[-3]; - - if (c_3 >= 0xe0 && c_3 < 0xf0 -#if CONFIG_UNICODE_SAFETY - && (c_3 >= 0xe1 || c_2 >= 0xa0) - && (c_3 != 0xed || c_2 < 0xa0) -#endif - ) - { - *puc = ((unsigned int) (c_3 & 0x0f) << 12) - | ((unsigned int) (c_2 ^ 0x80) << 6) - | (unsigned int) (c_1 ^ 0x80); - return s - 3; - } -#if CONFIG_UNICODE_SAFETY - if ((c_3 ^ 0x80) < 0x40) -#endif - if (s - 3 != start) - { - uint8_t c_4 = s[-4]; - - if (c_4 >= 0xf0 && c_4 < 0xf8 -#if CONFIG_UNICODE_SAFETY - && (c_4 >= 0xf1 || c_3 >= 0x90) - && (c_4 < 0xf4 || (c_4 == 0xf4 && c_3 < 0x90)) -#endif - ) - { - *puc = ((unsigned int) (c_4 & 0x07) << 18) - | ((unsigned int) (c_3 ^ 0x80) << 12) - | ((unsigned int) (c_2 ^ 0x80) << 6) - | (unsigned int) (c_1 ^ 0x80); - return s - 4; - } - } - } - } - } - return NULL; -} |