strcasecmp.c revision 1.1.1.1
1/* $NetBSD: strcasecmp.c,v 1.1.1.1 2016/01/13 03:15:30 christos Exp $ */ 2 3/* strcasecmp.c -- case insensitive string comparator 4 Copyright (C) 1998, 1999 Free Software Foundation, Inc. 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 2, or (at your option) 9 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, write to the Free Software Foundation, 18 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ 19 20#if HAVE_CONFIG_H 21# include <config.h> 22#endif 23 24#ifdef LENGTH_LIMIT 25# define STRXCASECMP_FUNCTION strncasecmp 26# define STRXCASECMP_DECLARE_N , size_t n 27# define LENGTH_LIMIT_EXPR(Expr) Expr 28#else 29# define STRXCASECMP_FUNCTION strcasecmp 30# define STRXCASECMP_DECLARE_N /* empty */ 31# define LENGTH_LIMIT_EXPR(Expr) 0 32#endif 33 34#include <sys/types.h> 35#include <ctype.h> 36 37#define TOLOWER(Ch) (isupper (Ch) ? tolower (Ch) : (Ch)) 38 39/* Compare {{no more than N characters of }}strings S1 and S2, 40 ignoring case, returning less than, equal to or 41 greater than zero if S1 is lexicographically less 42 than, equal to or greater than S2. */ 43 44int 45STRXCASECMP_FUNCTION (const char *s1, const char *s2 STRXCASECMP_DECLARE_N) 46{ 47 register const unsigned char *p1 = (const unsigned char *) s1; 48 register const unsigned char *p2 = (const unsigned char *) s2; 49 unsigned char c1, c2; 50 51 if (p1 == p2 || LENGTH_LIMIT_EXPR (n == 0)) 52 return 0; 53 54 do 55 { 56 c1 = TOLOWER (*p1); 57 c2 = TOLOWER (*p2); 58 59 if (LENGTH_LIMIT_EXPR (--n == 0) || c1 == '\0') 60 break; 61 62 ++p1; 63 ++p2; 64 } 65 while (c1 == c2); 66 67 return c1 - c2; 68} 69