kernel/lib/string/strcmp.c

   1 /*
   2  *  ZeX/OS
   3  *  Copyright (C) 2007  Tomas 'ZeXx86' Jedrzejek (zexx86@zexos.org)
   4  *  Copyright (C) 2010  Tomas 'ZeXx86' Jedrzejek (zexx86@zexos.org)
   5  *
   6  *  This program is free software: you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation, either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20
  21 #include <string.h>
  22
  23 /**
  24  * strcmp - Compare two strings
  25  * @cs: One string
  26  * @ct: Another string
  27  */
  28 int strcmp (const char *cs, const char *ct)
  29 {
  30         signed char res;
  31
  32         for (;;) {
  33                 if ((res = *cs - *ct++) || !*cs ++)
  34                         break;
  35         }
  36
  37         return res;
  38 }
  39
  40 /**
  41  * cstrcmp - Compare two words
  42  * @cs: One string
  43  * @ct: Another string
  44  */
  45 int cstrcmp (const char *cs, const char *ct)
  46 {
  47         int i;
  48
  49         for (i = 0; (unsigned) i < strlen (cs); i ++) {
  50                 if (cs[i] != ct[i])
  51                         return -1;
  52         }
  53
  54         if ((ct[i] == ' ' || ct[i] == '\0') || ct[i] == '\n')
  55                 return 0;
  56
  57         return -2;
  58 }
  59
  60 /**
  61  * strncmp - Compare two length-limited strings
  62  * @cs: One string
  63  * @ct: Another string
  64  * @count: The maximum number of bytes to compare
  65  */
  66 int strncmp (const char *cs, const char *ct, size_t count)
  67 {
  68         signed char res = 0;
  69
  70         while (count) {
  71                 if ((res = *cs - *ct ++) || !*cs ++)
  72                         break;
  73
  74                 count --;
  75         }
  76
  77         return res;
  78 }