lib/libc/string/wcscoll.c

   1 /*-
   2  * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
   3  * Copyright (c) 2002 Tim J. Robbins
   4  * All rights reserved.
   5  *
   6  * Copyright (c) 2011 The FreeBSD Foundation
   7  * All rights reserved.
   8  * Portions of this software were developed by David Chisnall
   9  * under sponsorship from the FreeBSD Foundation.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #include <sys/cdefs.h>
  34 __FBSDID("$FreeBSD$");
  35
  36 #include <errno.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39 #include <wchar.h>
  40 #include "collate.h"
  41
  42 int
  43 wcscoll_l(const wchar_t *ws1, const wchar_t *ws2, locale_t locale)
  44 {
  45         int len1, len2, pri1, pri2, ret;
  46         wchar_t *tr1 = NULL, *tr2 = NULL;
  47         int direc, pass;
  48
  49         FIX_LOCALE(locale);
  50         struct xlocale_collate *table =
  51                 (struct xlocale_collate*)locale->components[XLC_COLLATE];
  52
  53         if (table->__collate_load_error)
  54                 /*
  55                  * Locale has no special collating order or could not be
  56                  * loaded, do a fast binary comparison.
  57                  */
  58                 return (wcscmp(ws1, ws2));
  59
  60         ret = 0;
  61
  62         /*
  63          * Once upon a time we had code to try to optimize this, but
  64          * it turns out that you really can't make many assumptions
  65          * safely.  You absolutely have to run this pass by pass,
  66          * because some passes will be ignored for a given character,
  67          * while others will not.  Simpler locales will benefit from
  68          * having fewer passes, and most comparisons should resolve
  69          * during the primary pass anyway.
  70          *
  71          * Note that we do one final extra pass at the end to pick
  72          * up UNDEFINED elements.  There is special handling for them.
  73          */
  74         for (pass = 0; pass <= table->info->directive_count; pass++) {
  75
  76                 const int32_t *st1 = NULL;
  77                 const int32_t *st2 = NULL;
  78                 const wchar_t   *w1 = ws1;
  79                 const wchar_t   *w2 = ws2;
  80                 int check1, check2;
  81
  82                 /* special pass for UNDEFINED */
  83                 if (pass == table->info->directive_count) {
  84                         direc = DIRECTIVE_FORWARD | DIRECTIVE_UNDEFINED;
  85                 } else {
  86                         direc = table->info->directive[pass];
  87                 }
  88
  89                 if (direc & DIRECTIVE_BACKWARD) {
  90                         wchar_t *bp, *fp, c;
  91                         if ((tr1 = wcsdup(w1)) == NULL)
  92                                 goto fail;
  93                         bp = tr1;
  94                         fp = tr1 + wcslen(tr1) - 1;
  95                         while (bp < fp) {
  96                                 c = *bp;
  97                                 *bp++ = *fp;
  98                                 *fp-- = c;
  99                         }
 100                         if ((tr2 = wcsdup(w2)) == NULL)
 101                                 goto fail;
 102                         bp = tr2;
 103                         fp = tr2 + wcslen(tr2) - 1;
 104                         while (bp < fp) {
 105                                 c = *bp;
 106                                 *bp++ = *fp;
 107                                 *fp-- = c;
 108                         }
 109                         w1 = tr1;
 110                         w2 = tr2;
 111                 }
 112
 113                 if (direc & DIRECTIVE_POSITION) {
 114                         while (*w1 && *w2) {
 115                                 pri1 = pri2 = 0;
 116                                 check1 = check2 = 1;
 117                                 while ((pri1 == pri2) && (check1 || check2)) {
 118                                         if (check1) {
 119                                                 _collate_lookup(table, w1, &len1,
 120                                                     &pri1, pass, &st1);
 121                                                 if (pri1 < 0) {
 122                                                         errno = EINVAL;
 123                                                         goto fail;
 124                                                 }
 125                                                 if (!pri1) {
 126                                                         pri1 = COLLATE_MAX_PRIORITY;
 127                                                         st1 = NULL;
 128                                                 }
 129                                                 check1 = (st1 != NULL);
 130                                         }
 131                                         if (check2) {
 132                                                 _collate_lookup(table, w2, &len2,
 133                                                     &pri2, pass, &st2);
 134                                                 if (pri2 < 0) {
 135                                                         errno = EINVAL;
 136                                                         goto fail;
 137                                                 }
 138                                                 if (!pri2) {
 139                                                         pri2 = COLLATE_MAX_PRIORITY;
 140                                                         st2 = NULL;
 141                                                 }
 142                                                 check2 = (st2 != NULL);
 143                                         }
 144                                 }
 145                                 if (pri1 != pri2) {
 146                                         ret = pri1 - pri2;
 147                                         goto end;
 148                                 }
 149                                 w1 += len1;
 150                                 w2 += len2;
 151                         }
 152                 } else {
 153                         while (*w1 && *w2) {
 154                                 pri1 = pri2 = 0;
 155                                 check1 = check2 = 1;
 156                                 while ((pri1 == pri2) && (check1 || check2)) {
 157                                         while (check1 && *w1) {
 158                                                 _collate_lookup(table, w1,
 159                                                     &len1, &pri1, pass, &st1);
 160                                                 if (pri1 > 0)
 161                                                         break;
 162                                                 if (pri1 < 0) {
 163                                                         errno = EINVAL;
 164                                                         goto fail;
 165                                                 }
 166                                                 st1 = NULL;
 167                                                 w1 += 1;
 168                                         }
 169                                         check1 = (st1 != NULL);
 170                                         while (check2 && *w2) {
 171                                                 _collate_lookup(table, w2,
 172                                                     &len2, &pri2, pass, &st2);
 173                                                 if (pri2 > 0)
 174                                                         break;
 175                                                 if (pri2 < 0) {
 176                                                         errno = EINVAL;
 177                                                         goto fail;
 178                                                 }
 179                                                 st2 = NULL;
 180                                                 w2 += 1;
 181                                         }
 182                                         check2 = (st2 != NULL);
 183                                         if (!pri1 || !pri2)
 184                                                 break;
 185                                 }
 186                                 if (!pri1 || !pri2)
 187                                         break;
 188                                 if (pri1 != pri2) {
 189                                         ret = pri1 - pri2;
 190                                         goto end;
 191                                 }
 192                                 w1 += len1;
 193                                 w2 += len2;
 194                         }
 195                 }
 196                 if (!*w1) {
 197                         if (*w2) {
 198                                 ret = -(int)*w2;
 199                                 goto end;
 200                         }
 201                 } else {
 202                         ret = *w1;
 203                         goto end;
 204                 }
 205         }
 206         ret = 0;
 207
 208 end:
 209         free(tr1);
 210         free(tr2);
 211
 212         return (ret);
 213
 214 fail:
 215         ret = wcscmp(ws1, ws2);
 216         goto end;
 217 }
 218
 219 int
 220 wcscoll(const wchar_t *ws1, const wchar_t *ws2)
 221 {
 222         return wcscoll_l(ws1, ws2, __get_locale());
 223 }