/* strcasecmp.c -- case insensitive string comparator   Copyright (C) 1998, 1999 Free Software Foundation, Inc.   This program is free software; you can redistribute it and/or modify   it under the terms of the GNU General Public License as published by   the Free Software Foundation; either version 2, or (at your option)   any later version.   This program is distributed in the hope that it will be useful,   but WITHOUT ANY WARRANTY; without even the implied warranty of   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the   GNU General Public License for more details.   You should have received a copy of the GNU General Public License   along with this program; if not, write to the Free Software Foundation,   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */#if HAVE_CONFIG_H# include <config.h>#endif#ifdef LENGTH_LIMIT# define STRXCASECMP_FUNCTION strncasecmp# define STRXCASECMP_DECLARE_N , size_t n# define LENGTH_LIMIT_EXPR(Expr) Expr#else# define STRXCASECMP_FUNCTION strcasecmp# define STRXCASECMP_DECLARE_N /* empty */# define LENGTH_LIMIT_EXPR(Expr) 0#endif#include <sys/types.h>#include <ctype.h>#define TOLOWER(Ch) (isupper (Ch) ? tolower (Ch) : (Ch))/* Compare {{no more than N characters of }}strings S1 and S2,   ignoring case, returning less than, equal to or   greater than zero if S1 is lexicographically less   than, equal to or greater than S2.  */intSTRXCASECMP_FUNCTION (const char *s1, const char *s2 STRXCASECMP_DECLARE_N){  register const unsigned char *p1 = (const unsigned char *) s1;  register const unsigned char *p2 = (const unsigned char *) s2;  unsigned char c1, c2;  if (p1 == p2 || LENGTH_LIMIT_EXPR (n == 0))    return 0;  do    {      c1 = TOLOWER (*p1);      c2 = TOLOWER (*p2);      if (LENGTH_LIMIT_EXPR (--n == 0) || c1 == '\0')	break;      ++p1;      ++p2;    }  while (c1 == c2);  return c1 - c2;}