diff options
Diffstat (limited to 'libc/string/strcasecmp.c')
| -rw-r--r-- | libc/string/strcasecmp.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/libc/string/strcasecmp.c b/libc/string/strcasecmp.c new file mode 100644 index 0000000..12f3a09 --- /dev/null +++ b/libc/string/strcasecmp.c @@ -0,0 +1,105 @@ +/* $OpenBSD: strcasecmp.c,v 1.6 2005/08/08 08:05:37 espie Exp $ */ + +/* + * Copyright (c) 1987, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <string.h> + +typedef unsigned char u_char; + +/* + * This array is designed for mapping upper and lower case letter + * together for a case independent comparison. The mappings are + * based upon ascii character sequences. + */ +static const u_char charmap[] = { + '\000', '\001', '\002', '\003', '\004', '\005', '\006', '\007', + '\010', '\011', '\012', '\013', '\014', '\015', '\016', '\017', + '\020', '\021', '\022', '\023', '\024', '\025', '\026', '\027', + '\030', '\031', '\032', '\033', '\034', '\035', '\036', '\037', + '\040', '\041', '\042', '\043', '\044', '\045', '\046', '\047', + '\050', '\051', '\052', '\053', '\054', '\055', '\056', '\057', + '\060', '\061', '\062', '\063', '\064', '\065', '\066', '\067', + '\070', '\071', '\072', '\073', '\074', '\075', '\076', '\077', + '\100', '\141', '\142', '\143', '\144', '\145', '\146', '\147', + '\150', '\151', '\152', '\153', '\154', '\155', '\156', '\157', + '\160', '\161', '\162', '\163', '\164', '\165', '\166', '\167', + '\170', '\171', '\172', '\133', '\134', '\135', '\136', '\137', + '\140', '\141', '\142', '\143', '\144', '\145', '\146', '\147', + '\150', '\151', '\152', '\153', '\154', '\155', '\156', '\157', + '\160', '\161', '\162', '\163', '\164', '\165', '\166', '\167', + '\170', '\171', '\172', '\173', '\174', '\175', '\176', '\177', + '\200', '\201', '\202', '\203', '\204', '\205', '\206', '\207', + '\210', '\211', '\212', '\213', '\214', '\215', '\216', '\217', + '\220', '\221', '\222', '\223', '\224', '\225', '\226', '\227', + '\230', '\231', '\232', '\233', '\234', '\235', '\236', '\237', + '\240', '\241', '\242', '\243', '\244', '\245', '\246', '\247', + '\250', '\251', '\252', '\253', '\254', '\255', '\256', '\257', + '\260', '\261', '\262', '\263', '\264', '\265', '\266', '\267', + '\270', '\271', '\272', '\273', '\274', '\275', '\276', '\277', + '\300', '\301', '\302', '\303', '\304', '\305', '\306', '\307', + '\310', '\311', '\312', '\313', '\314', '\315', '\316', '\317', + '\320', '\321', '\322', '\323', '\324', '\325', '\326', '\327', + '\330', '\331', '\332', '\333', '\334', '\335', '\336', '\337', + '\340', '\341', '\342', '\343', '\344', '\345', '\346', '\347', + '\350', '\351', '\352', '\353', '\354', '\355', '\356', '\357', + '\360', '\361', '\362', '\363', '\364', '\365', '\366', '\367', + '\370', '\371', '\372', '\373', '\374', '\375', '\376', '\377', +}; + +int +strcasecmp(const char *s1, const char *s2) +{ + const u_char *cm = charmap; + const u_char *us1 = (const u_char *)s1; + const u_char *us2 = (const u_char *)s2; + + while (cm[*us1] == cm[*us2++]) + if (*us1++ == '\0') + return (0); + return (cm[*us1] - cm[*--us2]); +} + +int +strncasecmp(const char *s1, const char *s2, size_t n) +{ + if (n != 0) { + const u_char *cm = charmap; + const u_char *us1 = (const u_char *)s1; + const u_char *us2 = (const u_char *)s2; + + do { + if (cm[*us1] != cm[*us2++]) + return (cm[*us1] - cm[*--us2]); + if (*us1++ == '\0') + break; + } while (--n != 0); + } + return (0); +} |