1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
|
/* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
*
* Libmemcached library
*
* Copyright (C) 2011 Data Differential, http://datadifferential.com/
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
*
* * The names of its contributors may not be used to endorse or
* promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include <libmemcached/common.h>
struct bucket_t {
uint32_t master;
uint32_t forward;
};
struct memcached_virtual_bucket_t {
bool has_forward;
uint32_t size;
uint32_t replicas;
struct bucket_t buckets[];
};
memcached_return_t memcached_virtual_bucket_create(memcached_st *self,
const uint32_t *host_map,
const uint32_t *forward_map,
const uint32_t buckets,
const uint32_t replicas)
{
if (self == NULL || host_map == NULL || buckets == 0U)
{
return MEMCACHED_INVALID_ARGUMENTS;
}
memcached_virtual_bucket_free(self);
struct memcached_virtual_bucket_t *virtual_bucket= (struct memcached_virtual_bucket_t *)malloc(sizeof(struct memcached_virtual_bucket_t) + sizeof(struct bucket_t) *buckets);
if (virtual_bucket == NULL)
{
return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
}
virtual_bucket->size= buckets;
virtual_bucket->replicas= replicas;
self->virtual_bucket= virtual_bucket;
uint32_t x= 0;
for (; x < buckets; x++)
{
virtual_bucket->buckets[x].master= host_map[x];
if (forward_map)
{
virtual_bucket->buckets[x].forward= forward_map[x];
}
else
{
virtual_bucket->buckets[x].forward= 0;
}
}
return MEMCACHED_SUCCESS;
}
void memcached_virtual_bucket_free(memcached_st *self)
{
if (self)
{
if (self->virtual_bucket)
{
free(self->virtual_bucket);
self->virtual_bucket= NULL;
}
}
}
uint32_t memcached_virtual_bucket_get(const memcached_st *self, uint32_t digest)
{
if (self)
{
if (self->virtual_bucket)
{
if (self->virtual_bucket)
{
uint32_t result= (uint32_t) (digest & (self->virtual_bucket->size -1));
return self->virtual_bucket->buckets[result].master;
}
return (uint32_t) (digest & (self->number_of_hosts -1));
}
}
return 0;
}
|
