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Diffstat (limited to 'gl/strcasecmp.c')
-rw-r--r-- | gl/strcasecmp.c | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/gl/strcasecmp.c b/gl/strcasecmp.c new file mode 100644 index 00000000..0f0a742f --- /dev/null +++ b/gl/strcasecmp.c | |||
@@ -0,0 +1,62 @@ | |||
1 | /* Case-insensitive string comparison function. | ||
2 | Copyright (C) 1998-1999, 2005-2007, 2009-2013 Free Software Foundation, Inc. | ||
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 3, or (at your option) | ||
7 | 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 | ||
15 | along with this program; if not, see <http://www.gnu.org/licenses/>. */ | ||
16 | |||
17 | #include <config.h> | ||
18 | |||
19 | /* Specification. */ | ||
20 | #include <string.h> | ||
21 | |||
22 | #include <ctype.h> | ||
23 | #include <limits.h> | ||
24 | |||
25 | #define TOLOWER(Ch) (isupper (Ch) ? tolower (Ch) : (Ch)) | ||
26 | |||
27 | /* Compare strings S1 and S2, ignoring case, returning less than, equal to or | ||
28 | greater than zero if S1 is lexicographically less than, equal to or greater | ||
29 | than S2. | ||
30 | Note: This function does not work with multibyte strings! */ | ||
31 | |||
32 | int | ||
33 | strcasecmp (const char *s1, const char *s2) | ||
34 | { | ||
35 | const unsigned char *p1 = (const unsigned char *) s1; | ||
36 | const unsigned char *p2 = (const unsigned char *) s2; | ||
37 | unsigned char c1, c2; | ||
38 | |||
39 | if (p1 == p2) | ||
40 | return 0; | ||
41 | |||
42 | do | ||
43 | { | ||
44 | c1 = TOLOWER (*p1); | ||
45 | c2 = TOLOWER (*p2); | ||
46 | |||
47 | if (c1 == '\0') | ||
48 | break; | ||
49 | |||
50 | ++p1; | ||
51 | ++p2; | ||
52 | } | ||
53 | while (c1 == c2); | ||
54 | |||
55 | if (UCHAR_MAX <= INT_MAX) | ||
56 | return c1 - c2; | ||
57 | else | ||
58 | /* On machines where 'char' and 'int' are types of the same size, the | ||
59 | difference of two 'unsigned char' values - including the sign bit - | ||
60 | doesn't fit in an 'int'. */ | ||
61 | return (c1 > c2 ? 1 : c1 < c2 ? -1 : 0); | ||
62 | } | ||