1 /* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
5 * Copyright (C) 2011 Data Differential, http://datadifferential.com/
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39 #include <libmemcached/common.h>
46 struct memcached_virtual_bucket_t
{
50 struct bucket_t buckets
[];
53 memcached_return_t
memcached_virtual_bucket_create(memcached_st
*self
,
54 const uint32_t *host_map
,
55 const uint32_t *forward_map
,
56 const uint32_t buckets
,
57 const uint32_t replicas
)
59 if (! self
|| ! host_map
|| ! buckets
)
61 return MEMCACHED_INVALID_ARGUMENTS
;
64 memcached_virtual_bucket_free(self
);
66 struct memcached_virtual_bucket_t
*virtual_bucket
= (struct memcached_virtual_bucket_t
*)malloc(sizeof(struct memcached_virtual_bucket_t
) + sizeof(struct bucket_t
) *buckets
);
69 return MEMCACHED_MEMORY_ALLOCATION_FAILURE
;
71 virtual_bucket
->size
= buckets
;
72 virtual_bucket
->replicas
= replicas
;
73 self
->virtual_bucket
= virtual_bucket
;
76 for (; x
< buckets
; x
++)
78 virtual_bucket
->buckets
[x
].master
= host_map
[x
];
81 virtual_bucket
->buckets
[x
].forward
= forward_map
[x
];
85 virtual_bucket
->buckets
[x
].forward
= 0;
90 return MEMCACHED_SUCCESS
;
93 void memcached_virtual_bucket_free(memcached_st
*self
)
98 if (! self
->virtual_bucket
)
101 free(self
->virtual_bucket
);
102 self
->virtual_bucket
= NULL
;
105 uint32_t memcached_virtual_bucket_get(const memcached_st
*self
, uint32_t digest
)
110 if (! self
->virtual_bucket
)
113 if (self
->virtual_bucket
)
115 uint32_t result
= (uint32_t) (digest
& (self
->virtual_bucket
->size
-1));
116 return self
->virtual_bucket
->buckets
[result
].master
;
119 return (uint32_t) (digest
& (self
->number_of_hosts
-1));