| /* Case-insensitive string comparison function. |
| Copyright (C) 1998-1999, 2005-2020 Free Software Foundation, Inc. |
| Written by Bruno Haible <bruno@clisp.org>, 2005, |
| based on earlier glibc code. |
| |
| This program is free software: you can redistribute it and/or modify |
| it under the terms of the GNU 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 General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program. If not, see <https://www.gnu.org/licenses/>. */ |
| |
| #include <config.h> |
| |
| /* Specification. */ |
| #include <string.h> |
| |
| #include <ctype.h> |
| #include <limits.h> |
| |
| #include "mbuiter.h" |
| |
| #define TOLOWER(Ch) (isupper (Ch) ? tolower (Ch) : (Ch)) |
| |
| /* Compare the character strings S1 and S2, ignoring case, returning less than, |
| equal to or greater than zero if S1 is lexicographically less than, equal to |
| or greater than S2. |
| Note: This function may, in multibyte locales, return 0 for strings of |
| different lengths! */ |
| int |
| mbscasecmp (const char *s1, const char *s2) |
| { |
| if (s1 == s2) |
| return 0; |
| |
| /* Be careful not to look at the entire extent of s1 or s2 until needed. |
| This is useful because when two strings differ, the difference is |
| most often already in the very few first characters. */ |
| if (MB_CUR_MAX > 1) |
| { |
| mbui_iterator_t iter1; |
| mbui_iterator_t iter2; |
| |
| mbui_init (iter1, s1); |
| mbui_init (iter2, s2); |
| |
| while (mbui_avail (iter1) && mbui_avail (iter2)) |
| { |
| int cmp = mb_casecmp (mbui_cur (iter1), mbui_cur (iter2)); |
| |
| if (cmp != 0) |
| return cmp; |
| |
| mbui_advance (iter1); |
| mbui_advance (iter2); |
| } |
| if (mbui_avail (iter1)) |
| /* s2 terminated before s1. */ |
| return 1; |
| if (mbui_avail (iter2)) |
| /* s1 terminated before s2. */ |
| return -1; |
| return 0; |
| } |
| else |
| { |
| const unsigned char *p1 = (const unsigned char *) s1; |
| const unsigned char *p2 = (const unsigned char *) s2; |
| unsigned char c1, c2; |
| |
| do |
| { |
| c1 = TOLOWER (*p1); |
| c2 = TOLOWER (*p2); |
| |
| if (c1 == '\0') |
| break; |
| |
| ++p1; |
| ++p2; |
| } |
| while (c1 == c2); |
| |
| if (UCHAR_MAX <= INT_MAX) |
| return c1 - c2; |
| else |
| /* On machines where 'char' and 'int' are types of the same size, the |
| difference of two 'unsigned char' values - including the sign bit - |
| doesn't fit in an 'int'. */ |
| return (c1 > c2 ? 1 : c1 < c2 ? -1 : 0); |
| } |
| } |