xref: /illumos-gate/usr/src/lib/libresolv2/common/bsd/strcasecmp.c (revision e86c665f2e10cf29ac3b5f93b53c60bef762a690)
1 /*
2  * Copyright (c) 1987, 1993
3  *    The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  * 	This product includes software developed by the University of
16  * 	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include "port_before.h"
35 
36 #include <sys/param.h>
37 #include <sys/types.h>
38 #include <sys/cdefs.h>
39 
40 #include <string.h>
41 
42 #include "port_after.h"
43 
44 #ifndef NEED_STRCASECMP
45 int __strcasecmp_unneeded__;
46 #else
47 
48 /*%
49  * This array is designed for mapping upper and lower case letter
50  * together for a case independent comparison.  The mappings are
51  * based upon ascii character sequences.
52  */
53 static const u_char charmap[] = {
54 	0000, 0001, 0002, 0003, 0004, 0005, 0006, 0007,
55 	0010, 0011, 0012, 0013, 0014, 0015, 0016, 0017,
56 	0020, 0021, 0022, 0023, 0024, 0025, 0026, 0027,
57 	0030, 0031, 0032, 0033, 0034, 0035, 0036, 0037,
58 	0040, 0041, 0042, 0043, 0044, 0045, 0046, 0047,
59 	0050, 0051, 0052, 0053, 0054, 0055, 0056, 0057,
60 	0060, 0061, 0062, 0063, 0064, 0065, 0066, 0067,
61 	0070, 0071, 0072, 0073, 0074, 0075, 0076, 0077,
62 	0100, 0141, 0142, 0143, 0144, 0145, 0146, 0147,
63 	0150, 0151, 0152, 0153, 0154, 0155, 0156, 0157,
64 	0160, 0161, 0162, 0163, 0164, 0165, 0166, 0167,
65 	0170, 0171, 0172, 0133, 0134, 0135, 0136, 0137,
66 	0140, 0141, 0142, 0143, 0144, 0145, 0146, 0147,
67 	0150, 0151, 0152, 0153, 0154, 0155, 0156, 0157,
68 	0160, 0161, 0162, 0163, 0164, 0165, 0166, 0167,
69 	0170, 0171, 0172, 0173, 0174, 0175, 0176, 0177,
70 	0200, 0201, 0202, 0203, 0204, 0205, 0206, 0207,
71 	0210, 0211, 0212, 0213, 0214, 0215, 0216, 0217,
72 	0220, 0221, 0222, 0223, 0224, 0225, 0226, 0227,
73 	0230, 0231, 0232, 0233, 0234, 0235, 0236, 0237,
74 	0240, 0241, 0242, 0243, 0244, 0245, 0246, 0247,
75 	0250, 0251, 0252, 0253, 0254, 0255, 0256, 0257,
76 	0260, 0261, 0262, 0263, 0264, 0265, 0266, 0267,
77 	0270, 0271, 0272, 0273, 0274, 0275, 0276, 0277,
78 	0300, 0301, 0302, 0303, 0304, 0305, 0306, 0307,
79 	0310, 0311, 0312, 0313, 0314, 0315, 0316, 0317,
80 	0320, 0321, 0322, 0323, 0324, 0325, 0326, 0327,
81 	0330, 0331, 0332, 0333, 0334, 0335, 0336, 0337,
82 	0340, 0341, 0342, 0343, 0344, 0345, 0346, 0347,
83 	0350, 0351, 0352, 0353, 0354, 0355, 0356, 0357,
84 	0360, 0361, 0362, 0363, 0364, 0365, 0366, 0367,
85 	0370, 0371, 0372, 0373, 0374, 0375, 0376, 0377
86 };
87 
88 int
89 strcasecmp(const char *s1, const char *s2) {
90 	const u_char *cm = charmap,
91 		     *us1 = (const u_char *)s1,
92 		     *us2 = (const u_char *)s2;
93 
94 	while (cm[*us1] == cm[*us2++])
95 		if (*us1++ == '\0')
96 			return (0);
97 	return (cm[*us1] - cm[*--us2]);
98 }
99 
100 int
101 strncasecmp(const char *s1, const char *s2, size_t n) {
102 	if (n != 0) {
103 		const u_char *cm = charmap,
104 			     *us1 = (const u_char *)s1,
105 			     *us2 = (const u_char *)s2;
106 
107 		do {
108 			if (cm[*us1] != cm[*us2++])
109 				return (cm[*us1] - cm[*--us2]);
110 			if (*us1++ == '\0')
111 				break;
112 		} while (--n != 0);
113 	}
114 	return (0);
115 }
116 
117 #endif /*NEED_STRCASECMP*/
118 
119 /*! \file */
120