view lib/strncasecmp.c @ 16366:bb182ee4a09d

maint: replace FSF snail-mail addresses with URLs * config/argz.mk, lib/accept4.c, lib/alignof.h, lib/alloca.in.h: * lib/alphasort.c, lib/arcfour.c, lib/arcfour.h, lib/arctwo.c: * lib/arctwo.h, lib/argz.c, lib/arpa_inet.in.h, lib/asnprintf.c: * lib/asprintf.c, lib/assert.in.h, lib/base32.c, lib/base32.h: * lib/base64.c, lib/base64.h, lib/c-ctype.c, lib/c-ctype.h: * lib/c-strcase.h, lib/c-strcasecmp.c, lib/c-strncasecmp.c: * lib/check-version.c, lib/check-version.h, lib/config.charset: * lib/ctype.in.h, lib/des.c, lib/des.h, lib/dup3.c, lib/errno.in.h: * lib/float+.h, lib/fnmatch.c, lib/fnmatch.in.h, lib/fnmatch_loop.c: * lib/fseeko.c, lib/gai_strerror.c, lib/gc-gnulib.c: * lib/gc-libgcrypt.c, lib/gc-pbkdf2-sha1.c, lib/gc.h: * lib/getaddrinfo.c, lib/getdelim.c, lib/getfilecon.c, lib/getline.c: * lib/getlogin_r.c, lib/getpass.c, lib/getpass.h, lib/gettext.h: * lib/gettimeofday.c, lib/glob.in.h, lib/glthread/cond.c: * lib/glthread/cond.h, lib/glthread/lock.c, lib/glthread/lock.h: * lib/glthread/thread.c, lib/glthread/thread.h: * lib/glthread/threadlib.c, lib/glthread/yield.h, lib/hmac-md5.c: * lib/hmac-sha1.c, lib/hmac.h, lib/iconv.c, lib/iconv.in.h: * lib/iconv_close.c, lib/iconv_open.c, lib/inet_ntop.c, lib/isfinite.c: * lib/isinf.c, lib/iswblank.c, lib/langinfo.in.h, lib/link.c: * lib/localcharset.c, lib/localcharset.h, lib/lseek.c, lib/malloc.c: * lib/malloca.c, lib/malloca.h, lib/md2.c, lib/md2.h, lib/md4.c: * lib/md4.h, lib/md5.c, lib/md5.h, lib/memmem.c, lib/mempcpy.c: * lib/memset.c, lib/memxor.c, lib/memxor.h, lib/minmax.h, lib/mktime.c: * lib/msvc-inval.c, lib/msvc-inval.h, lib/msvc-nothrow.c: * lib/msvc-nothrow.h, lib/netdb.in.h, lib/netinet_in.in.h, lib/nproc.c: * lib/nproc.h, lib/obstack_printf.c, lib/pathmax.h, lib/pipe.c: * lib/pipe2.c, lib/poll.c, lib/poll.in.h, lib/printf-args.c: * lib/printf-args.h, lib/printf-parse.c, lib/printf-parse.h: * lib/pselect.c, lib/pthread.in.h, lib/pty-private.h, lib/pty.in.h: * lib/read-file.c, lib/read-file.h, lib/ref-add.sin, lib/ref-del.sin: * lib/regcomp.c, lib/regex.c, lib/regex.h, lib/regex_internal.c: * lib/regex_internal.h, lib/regexec.c, lib/rijndael-alg-fst.c: * lib/rijndael-alg-fst.h, lib/rijndael-api-fst.c: * lib/rijndael-api-fst.h, lib/rint.c, lib/rintf.c, lib/rintl.c: * lib/round.c, lib/roundf.c, lib/roundl.c, lib/scandir.c, lib/select.c: * lib/sha1.c, lib/sha1.h, lib/size_max.h, lib/snprintf.c: * lib/stdalign.in.h, lib/stdarg.in.h, lib/stdbool.in.h: * lib/stddef.in.h, lib/stdint.in.h, lib/stdio.in.h, lib/str-kmp.h: * lib/str-two-way.h, lib/strcasecmp.c, lib/strcasestr.c, lib/strdup.c: * lib/striconv.c, lib/striconv.h, lib/string.in.h, lib/strings.in.h: * lib/strncasecmp.c, lib/strndup.c, lib/strnlen.c, lib/strpbrk.c: * lib/strptime.c, lib/strsep.c, lib/strstr.c, lib/strverscmp.c: * lib/sys_file.in.h, lib/sys_ioctl.in.h, lib/sys_select.in.h: * lib/sys_socket.in.h, lib/sys_stat.in.h, lib/sys_time.in.h: * lib/sys_times.in.h, lib/sys_types.in.h, lib/sys_uio.in.h: * lib/sys_utsname.in.h, lib/sys_wait.in.h, lib/tcgetsid.c: * lib/termios.in.h, lib/time.in.h, lib/time_r.c, lib/timegm.c: * lib/times.c, lib/unictype/3level.h, lib/unictype/3levelbit.h: * lib/unistd.in.h, lib/vasnprintf.c, lib/vasnprintf.h, lib/vasprintf.c: * lib/vsnprintf.c, lib/waitpid.c, lib/wchar.in.h, lib/wctype.in.h: * lib/xsize.h, tests/test-closein.c, tests/test-des.c: * tests/test-fclose.c, tests/test-fgetc.c, tests/test-filevercmp.c: * tests/test-fputc.c, tests/test-fread.c, tests/test-fwrite.c: * tests/test-gc-arcfour.c, tests/test-gc-arctwo.c, tests/test-gc-des.c: * tests/test-gc-hmac-md5.c, tests/test-gc-hmac-sha1.c: * tests/test-gc-md2.c, tests/test-gc-md4.c, tests/test-gc-md5.c: * tests/test-gc-pbkdf2-sha1.c, tests/test-gc-rijndael.c: * tests/test-gc-sha1.c, tests/test-gc.c, tests/test-getdelim.c: * tests/test-getline.c, tests/test-getndelim2.c, tests/test-md2.c: * tests/test-md4.c, tests/test-parse-datetime.c, tests/test-perror.c: * tests/test-perror2.c, tests/test-pipe.c, tests/test-pipe2.c: * tests/test-poll.c, tests/test-quotearg-simple.c: * tests/test-quotearg.c, tests/test-quotearg.h: * tests/test-round-ieee.c, tests/test-round1.c: * tests/test-roundf-ieee.c, tests/test-roundf1.c: * tests/test-roundl-ieee.c, tests/test-roundl.c: * tests/test-safe-alloc.c, tests/test-sigpipe.c: * tests/test-spawn-pipe-child.c, tests/test-spawn-pipe-main.c: * tests/test-strerror.c, tests/test-strerror_r.c: * tests/test-strsignal.c, tests/test-strverscmp.c: * tests/test-xmemdup0.c: Replace FSF snail mail addresses with URLs, as per GNU coding standards. See glibc bug <http://sourceware.org/bugzilla/show_bug.cgi?id=13673>.
author Paul Eggert <eggert@cs.ucla.edu>
date Thu, 09 Feb 2012 21:39:05 -0800
parents 8250f2777afc
children e542fd46ad6f
line wrap: on
line source

/* strncasecmp.c -- case insensitive string comparator
   Copyright (C) 1998-1999, 2005-2007, 2009-2012 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, see <http://www.gnu.org/licenses/>.  */

#include <config.h>

/* Specification.  */
#include <string.h>

#include <ctype.h>
#include <limits.h>

#define TOLOWER(Ch) (isupper (Ch) ? tolower (Ch) : (Ch))

/* Compare no more than N bytes 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.
   Note: This function cannot work correctly in multibyte locales.  */

int
strncasecmp (const char *s1, const char *s2, size_t 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 || n == 0)
    return 0;

  do
    {
      c1 = TOLOWER (*p1);
      c2 = TOLOWER (*p2);

      if (--n == 0 || c1 == '\0')
        break;

      ++p1;
      ++p2;
    }
  while (c1 == c2);

  if (UCHAR_MAX <= INT_MAX)
    return c1 - c2;
  else
    /* On machines where 'char' and 'int' are types of the same size, the
       difference of two 'unsigned char' values - including the sign bit -
       doesn't fit in an 'int'.  */
    return (c1 > c2 ? 1 : c1 < c2 ? -1 : 0);
}