/* Locale-specific memory comparison.
- Copyright 1999, 2000 Free Software Foundation, Inc.
- This program is free software; you can redistribute it and/or modify
+ Copyright (C) 1999, 2002, 2003, 2004, 2006 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.
+ the Free Software Foundation; either version 3 of the License, 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
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. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* Contributed by Paul Eggert <eggert@twinsun.com>. */
-#if HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include <config.h>
-#if HAVE_STRING_H
-# include <string.h>
-#endif
+#include "memcoll.h"
+
+#include <errno.h>
+#include <string.h>
/* Compare S1 (with length S1LEN) and S2 (with length S2LEN) according
to the LC_COLLATE locale. S1 and S2 do not overlap, and are not
- adjacent. Temporarily modify the bytes after S1 and S2, but
- restore their original contents before returning. */
+ adjacent. Perhaps temporarily modify the bytes after S1 and S2,
+ but restore their original contents before returning. Set errno to an
+ error number if there is an error, and to zero otherwise. */
int
memcoll (char *s1, size_t s1len, char *s2, size_t s2len)
{
int diff;
- char n1 = s1[s1len];
- char n2 = s2[s2len];
- s1[s1len++] = '\0';
- s2[s2len++] = '\0';
+#if HAVE_STRCOLL
- while (! (diff = strcoll (s1, s2)))
+ /* strcoll is slow on many platforms, so check for the common case
+ where the arguments are bytewise equal. Otherwise, walk through
+ the buffers using strcoll on each substring. */
+
+ if (s1len == s2len && memcmp (s1, s2, s1len) == 0)
{
- /* strcoll found no difference, but perhaps it was fooled by NUL
- characters in the data. Work around this problem by advancing
- past the NUL chars. */
- size_t size1 = strlen (s1) + 1;
- size_t size2 = strlen (s2) + 1;
- s1 += size1;
- s2 += size2;
- s1len -= size1;
- s2len -= size2;
-
- if (s1len == 0)
- {
- if (s2len != 0)
- diff = -1;
- break;
- }
- else if (s2len == 0)
+ errno = 0;
+ diff = 0;
+ }
+ else
+ {
+ char n1 = s1[s1len];
+ char n2 = s2[s2len];
+
+ s1[s1len++] = '\0';
+ s2[s2len++] = '\0';
+
+ while (! (errno = 0, (diff = strcoll (s1, s2)) || errno))
{
- diff = 1;
- break;
+ /* strcoll found no difference, but perhaps it was fooled by NUL
+ characters in the data. Work around this problem by advancing
+ past the NUL chars. */
+ size_t size1 = strlen (s1) + 1;
+ size_t size2 = strlen (s2) + 1;
+ s1 += size1;
+ s2 += size2;
+ s1len -= size1;
+ s2len -= size2;
+
+ if (s1len == 0)
+ {
+ if (s2len != 0)
+ diff = -1;
+ break;
+ }
+ else if (s2len == 0)
+ {
+ diff = 1;
+ break;
+ }
}
+
+ s1[s1len - 1] = n1;
+ s2[s2len - 1] = n2;
}
- s1[s1len - 1] = n1;
- s2[s2len - 1] = n2;
+#else
+
+ diff = memcmp (s1, s2, s1len < s2len ? s1len : s2len);
+ if (! diff)
+ diff = s1len < s2len ? -1 : s1len != s2len;
+ errno = 0;
+
+#endif
return diff;
}