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/*-
* Public Domain 2014-2016 MongoDB, Inc.
* Public Domain 2008-2014 WiredTiger, Inc.
*
* This is free and unencumbered software released into the public domain.
*
* Anyone is free to copy, modify, publish, use, compile, sell, or
* distribute this software, either in source code form or as a compiled
* binary, for any purpose, commercial or non-commercial, and by any
* means.
*
* In jurisdictions that recognize copyright laws, the author or authors
* of this software dedicate any and all copyright interest in the
* software to the public domain. We make this dedication for the benefit
* of the public at large and to the detriment of our heirs and
* successors. We intend this dedication to be an overt act of
* relinquishment in perpetuity of all present and future rights to this
* software under copyright law.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
#include <string.h>
#include <wiredtiger_ext.h>
/*
* collate_reverse --
* WiredTiger reverse collation.
*/
static int
collate_reverse(WT_COLLATOR *collator,
WT_SESSION *session, const WT_ITEM *k1, const WT_ITEM *k2, int *ret)
{
size_t len;
int cmp;
(void)collator; /* Unused */
(void)session;
len = (k1->size < k2->size) ? k1->size : k2->size;
cmp = memcmp(k1->data, k2->data, len);
if (cmp < 0)
*ret = 1;
else if (cmp > 0)
*ret = -1;
else if (k1->size < k2->size)
*ret = 1;
else if (k1->size > k2->size)
*ret = -1;
else
*ret = 0;
return (0);
}
static WT_COLLATOR reverse_collator = { collate_reverse, NULL, NULL };
/*
* wiredtiger_extension_init --
* WiredTiger reverse collation extension.
*/
int
wiredtiger_extension_init(WT_CONNECTION *connection, WT_CONFIG_ARG *config)
{
(void)config; /* Unused parameters */
return (connection->add_collator(
connection, "reverse", &reverse_collator, NULL));
}
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