/* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
*
* Libmemcached library
*
* Copyright (C) 2011 Data Differential, http://datadifferential.com/
* Copyright (C) 2006-2010 Brian Aker 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>
#include "libmemcached/assert.hpp"
#include <cmath>
#include <sys/time.h>
/* Protoypes (static) */
static memcached_return_t update_continuum(Memcached *ptr);
static int compare_servers(const void *p1, const void *p2)
{
const memcached_instance_st * a= (const memcached_instance_st *)p1;
const memcached_instance_st * b= (const memcached_instance_st *)p2;
int return_value= strcmp(a->_hostname, b->_hostname);
if (return_value == 0)
{
return_value= int(a->port() - b->port());
}
return return_value;
}
static void sort_hosts(Memcached *ptr)
{
if (memcached_server_count(ptr))
{
qsort(memcached_instance_list(ptr), memcached_server_count(ptr), sizeof(memcached_instance_st), compare_servers);
}
}
memcached_return_t run_distribution(Memcached *ptr)
{
if (ptr->flags.use_sort_hosts)
{
sort_hosts(ptr);
}
switch (ptr->distribution)
{
case MEMCACHED_DISTRIBUTION_CONSISTENT:
case MEMCACHED_DISTRIBUTION_CONSISTENT_KETAMA:
case MEMCACHED_DISTRIBUTION_CONSISTENT_KETAMA_SPY:
case MEMCACHED_DISTRIBUTION_CONSISTENT_WEIGHTED:
return update_continuum(ptr);
case MEMCACHED_DISTRIBUTION_VIRTUAL_BUCKET:
case MEMCACHED_DISTRIBUTION_MODULA:
break;
case MEMCACHED_DISTRIBUTION_RANDOM:
srandom((uint32_t) time(NULL));
break;
case MEMCACHED_DISTRIBUTION_CONSISTENT_MAX:
default:
assert_msg(0, "Invalid distribution type passed to run_distribution()");
}
return MEMCACHED_SUCCESS;
}
static uint32_t ketama_server_hash(const char *key, size_t key_length, uint32_t alignment)
{
unsigned char results[16];
libhashkit_md5_signature((unsigned char*)key, key_length, results);
return ((uint32_t) (results[3 + alignment * 4] & 0xFF) << 24)
| ((uint32_t) (results[2 + alignment * 4] & 0xFF) << 16)
| ((uint32_t) (results[1 + alignment * 4] & 0xFF) << 8)
| (results[0 + alignment * 4] & 0xFF);
}
static int continuum_item_cmp(const void *t1, const void *t2)
{
memcached_continuum_item_st *ct1= (memcached_continuum_item_st *)t1;
memcached_continuum_item_st *ct2= (memcached_continuum_item_st *)t2;
/* Why 153? Hmmm... */
WATCHPOINT_ASSERT(ct1->value != 153);
if (ct1->value == ct2->value)
{
return 0;
}
else if (ct1->value > ct2->value)
{
return 1;
}
else
{
return -1;
}
}
static memcached_return_t update_continuum(Memcached *ptr)
{
uint32_t continuum_index= 0;
uint32_t pointer_counter= 0;
uint32_t pointer_per_server= MEMCACHED_POINTS_PER_SERVER;
uint32_t pointer_per_hash= 1;
uint32_t live_servers= 0;
struct timeval now;
if (gettimeofday(&now, NULL))
{
return memcached_set_errno(*ptr, errno, MEMCACHED_AT);
}
memcached_instance_st* list= memcached_instance_list(ptr);
/* count live servers (those without a retry delay set) */
bool is_auto_ejecting= _is_auto_eject_host(ptr);
if (is_auto_ejecting)
{
live_servers= 0;
ptr->ketama.next_distribution_rebuild= 0;
for (uint32_t host_index= 0; host_index < memcached_server_count(ptr); ++host_index)
{
if (list[host_index].next_retry <= now.tv_sec)
{
live_servers++;
}
else
{
if (ptr->ketama.next_distribution_rebuild == 0 or list[host_index].next_retry < ptr->ketama.next_distribution_rebuild)
{
ptr->ketama.next_distribution_rebuild= list[host_index].next_retry;
}
}
}
}
else
{
live_servers= memcached_server_count(ptr);
}
uint32_t points_per_server= (uint32_t) (memcached_is_weighted_ketama(ptr) ? MEMCACHED_POINTS_PER_SERVER_KETAMA : MEMCACHED_POINTS_PER_SERVER);
if (live_servers == 0)
{
return MEMCACHED_SUCCESS;
}
if (live_servers > ptr->ketama.continuum_count)
{
memcached_continuum_item_st *new_ptr;
new_ptr= libmemcached_xrealloc(ptr, ptr->ketama.continuum, (live_servers + MEMCACHED_CONTINUUM_ADDITION) * points_per_server, memcached_continuum_item_st);
if (new_ptr == 0)
{
return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
}
ptr->ketama.continuum= new_ptr;
ptr->ketama.continuum_count= live_servers + MEMCACHED_CONTINUUM_ADDITION;
}
assert_msg(ptr->ketama.continuum, "Programmer Error, empty ketama continuum");
uint64_t total_weight= 0;
if (memcached_is_weighted_ketama(ptr))
{
for (uint32_t host_index = 0; host_index < memcached_server_count(ptr); ++host_index)
{
if (is_auto_ejecting == false or list[host_index].next_retry <= now.tv_sec)
{
total_weight += list[host_index].weight;
}
}
}
for (uint32_t host_index= 0; host_index < memcached_server_count(ptr); ++host_index)
{
if (is_auto_ejecting and list[host_index].next_retry > now.tv_sec)
{
continue;
}
if (memcached_is_weighted_ketama(ptr))
{
float pct= (float)list[host_index].weight / (float)total_weight;
pointer_per_server= (uint32_t) ((::floor((float) (pct * MEMCACHED_POINTS_PER_SERVER_KETAMA / 4 * (float)live_servers + 0.0000000001))) * 4);
pointer_per_hash= 4;
if (DEBUG)
{
printf("ketama_weighted:%s|%d|%llu|%u\n",
list[host_index]._hostname,
list[host_index].port(),
(unsigned long long)list[host_index].weight,
pointer_per_server);
}
}
if (ptr->distribution == MEMCACHED_DISTRIBUTION_CONSISTENT_KETAMA_SPY)
{
for (uint32_t pointer_index= 0;
pointer_index < pointer_per_server / pointer_per_hash;
pointer_index++)
{
char sort_host[1 +MEMCACHED_NI_MAXHOST +1 +MEMCACHED_NI_MAXSERV +1 + MEMCACHED_NI_MAXSERV ]= "";
int sort_host_length;
// Spymemcached ketema key format is: hostname/ip:port-index
// If hostname is not available then: /ip:port-index
sort_host_length= snprintf(sort_host, sizeof(sort_host),
"/%s:%u-%u",
list[host_index]._hostname,
(uint32_t)list[host_index].port(),
pointer_index);
if (size_t(sort_host_length) >= sizeof(sort_host) or sort_host_length < 0)
{
return memcached_set_error(*ptr, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT,
memcached_literal_param("snprintf(sizeof(sort_host))"));
}
if (DEBUG)
{
fprintf(stdout, "update_continuum: key is %s\n", sort_host);
}
if (memcached_is_weighted_ketama(ptr))
{
for (uint32_t x= 0; x < pointer_per_hash; x++)
{
uint32_t value= ketama_server_hash(sort_host, (size_t)sort_host_length, x);
ptr->ketama.continuum[continuum_index].index= host_index;
ptr->ketama.continuum[continuum_index++].value= value;
}
}
else
{
uint32_t value= hashkit_digest(&ptr->hashkit, sort_host, (size_t)sort_host_length);
ptr->ketama.continuum[continuum_index].index= host_index;
ptr->ketama.continuum[continuum_index++].value= value;
}
}
}
else
{
for (uint32_t pointer_index= 1;
pointer_index <= pointer_per_server / pointer_per_hash;
pointer_index++)
{
char sort_host[MEMCACHED_NI_MAXHOST +1 +MEMCACHED_NI_MAXSERV +1 +MEMCACHED_NI_MAXSERV]= "";
int sort_host_length;
if (list[host_index].port() == MEMCACHED_DEFAULT_PORT)
{
sort_host_length= snprintf(sort_host, sizeof(sort_host),
"%s-%u",
list[host_index]._hostname,
pointer_index - 1);
}
else
{
sort_host_length= snprintf(sort_host, sizeof(sort_host),
"%s:%u-%u",
list[host_index]._hostname,
(uint32_t)list[host_index].port(),
pointer_index - 1);
}
if (size_t(sort_host_length) >= sizeof(sort_host) or sort_host_length < 0)
{
return memcached_set_error(*ptr, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT,
memcached_literal_param("snprintf(sizeof(sort_host)))"));
}
if (memcached_is_weighted_ketama(ptr))
{
for (uint32_t x = 0; x < pointer_per_hash; x++)
{
uint32_t value= ketama_server_hash(sort_host, (size_t)sort_host_length, x);
ptr->ketama.continuum[continuum_index].index= host_index;
ptr->ketama.continuum[continuum_index++].value= value;
}
}
else
{
uint32_t value= hashkit_digest(&ptr->hashkit, sort_host, (size_t)sort_host_length);
ptr->ketama.continuum[continuum_index].index= host_index;
ptr->ketama.continuum[continuum_index++].value= value;
}
}
}
pointer_counter+= pointer_per_server;
}
assert_msg(ptr, "Programmer Error, no valid ptr");
assert_msg(ptr->ketama.continuum, "Programmer Error, empty ketama continuum");
assert_msg(memcached_server_count(ptr) * MEMCACHED_POINTS_PER_SERVER <= MEMCACHED_CONTINUUM_SIZE, "invalid size information being given to qsort()");
ptr->ketama.continuum_points_counter= pointer_counter;
qsort(ptr->ketama.continuum, ptr->ketama.continuum_points_counter, sizeof(memcached_continuum_item_st), continuum_item_cmp);
if (DEBUG)
{
for (uint32_t pointer_index= 0; memcached_server_count(ptr) && pointer_index < ((live_servers * MEMCACHED_POINTS_PER_SERVER) - 1); pointer_index++)
{
WATCHPOINT_ASSERT(ptr->ketama.continuum[pointer_index].value <= ptr->ketama.continuum[pointer_index + 1].value);
}
}
return MEMCACHED_SUCCESS;
}
static memcached_return_t server_add(Memcached *memc,
const memcached_string_t& hostname,
in_port_t port,
uint32_t weight,
memcached_connection_t type)
{
assert_msg(memc, "Programmer mistake, somehow server_add() was passed a NULL memcached_st");
if (memc->number_of_hosts)
{
assert(memcached_instance_list(memc));
}
if (memcached_instance_list(memc))
{
assert(memc->number_of_hosts);
}
uint32_t host_list_size= memc->number_of_hosts +1;
memcached_instance_st* new_host_list= libmemcached_xrealloc(memc, memcached_instance_list(memc), host_list_size, memcached_instance_st);
if (new_host_list == NULL)
{
return memcached_set_error(*memc, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT);
}
memcached_instance_set(memc, new_host_list, host_list_size);
assert(memc->number_of_hosts == host_list_size);
/* TODO: Check return type */
memcached_instance_st* instance= memcached_instance_fetch(memc, memcached_server_count(memc) -1);
if (__instance_create_with(memc, instance, hostname, port, weight, type) == NULL)
{
return memcached_set_error(*memc, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT);
}
if (weight > 1)
{
if (memcached_is_consistent_distribution(memc))
{
memcached_set_weighted_ketama(memc, true);
}
}
return run_distribution(memc);
}
memcached_return_t memcached_server_push(memcached_st *shell, const memcached_server_list_st list)
{
if (list == NULL)
{
return MEMCACHED_SUCCESS;
}
Memcached* ptr= memcached2Memcached(shell);
if (ptr)
{
uint32_t original_host_size= memcached_server_count(ptr);
uint32_t count= memcached_server_list_count(list);
uint32_t host_list_size= count +original_host_size;
memcached_instance_st* new_host_list= libmemcached_xrealloc(ptr, memcached_instance_list(ptr), host_list_size, memcached_instance_st);
if (new_host_list == NULL)
{
return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
}
memcached_instance_set(ptr, new_host_list, host_list_size);
ptr->state.is_parsing= true;
for (uint32_t x= 0; x < count; ++x, ++original_host_size)
{
WATCHPOINT_ASSERT(list[x].hostname[0] != 0);
// We have extended the array, and now we will find it, and use it.
memcached_instance_st* instance= memcached_instance_fetch(ptr, original_host_size);
WATCHPOINT_ASSERT(instance);
memcached_string_t hostname= { memcached_string_make_from_cstr(list[x].hostname) };
if (__instance_create_with(ptr, instance,
hostname,
list[x].port, list[x].weight, list[x].type) == NULL)
{
ptr->state.is_parsing= false;
return memcached_set_error(*ptr, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT);
}
if (list[x].weight > 1)
{
memcached_set_weighted_ketama(ptr, true);
}
}
ptr->state.is_parsing= false;
return run_distribution(ptr);
}
return MEMCACHED_INVALID_ARGUMENTS;
}
memcached_return_t memcached_instance_push(memcached_st *ptr, const struct memcached_instance_st* list, uint32_t number_of_hosts)
{
if (list == NULL)
{
return MEMCACHED_SUCCESS;
}
uint32_t original_host_size= memcached_server_count(ptr);
uint32_t host_list_size= number_of_hosts +original_host_size;
memcached_instance_st* new_host_list= libmemcached_xrealloc(ptr, memcached_instance_list(ptr), host_list_size, memcached_instance_st);
if (new_host_list == NULL)
{
return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
}
memcached_instance_set(ptr, new_host_list, host_list_size);
// We don't bother with lookups for this operation
ptr->state.is_parsing= true;
// We use original_host_size since size will now point to the first new
// instance allocated.
for (uint32_t x= 0; x < number_of_hosts; ++x, ++original_host_size)
{
WATCHPOINT_ASSERT(list[x]._hostname[0] != 0);
// We have extended the array, and now we will find it, and use it.
memcached_instance_st* instance= memcached_instance_fetch(ptr, original_host_size);
WATCHPOINT_ASSERT(instance);
memcached_string_t hostname= { memcached_string_make_from_cstr(list[x]._hostname) };
if (__instance_create_with(ptr, instance,
hostname,
list[x].port(), list[x].weight, list[x].type) == NULL)
{
ptr->state.is_parsing= false;
return memcached_set_error(*ptr, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT);
}
if (list[x].weight > 1)
{
memcached_set_weighted_ketama(ptr, true);
}
}
ptr->state.is_parsing= false;
return run_distribution(ptr);
}
memcached_return_t memcached_server_add_unix_socket(memcached_st *ptr,
const char *filename)
{
return memcached_server_add_unix_socket_with_weight(ptr, filename, 0);
}
memcached_return_t memcached_server_add_unix_socket_with_weight(memcached_st *shell,
const char *filename,
uint32_t weight)
{
Memcached* ptr= memcached2Memcached(shell);
if (ptr)
{
memcached_string_t _filename= { memcached_string_make_from_cstr(filename) };
if (memcached_is_valid_filename(_filename) == false)
{
return memcached_set_error(*ptr, MEMCACHED_INVALID_ARGUMENTS, MEMCACHED_AT, memcached_literal_param("Invalid filename for socket provided"));
}
return server_add(ptr, _filename, 0, weight, MEMCACHED_CONNECTION_UNIX_SOCKET);
}
return MEMCACHED_FAILURE;
}
memcached_return_t memcached_server_add_udp(memcached_st *ptr,
const char *hostname,
in_port_t port)
{
return memcached_server_add_udp_with_weight(ptr, hostname, port, 0);
}
memcached_return_t memcached_server_add_udp_with_weight(memcached_st *shell,
const char *,
in_port_t,
uint32_t)
{
Memcached* self= memcached2Memcached(shell);
if (self)
{
return memcached_set_error(*self, MEMCACHED_DEPRECATED, MEMCACHED_AT);
}
return MEMCACHED_INVALID_ARGUMENTS;
}
memcached_return_t memcached_server_add(memcached_st *shell,
const char *hostname,
in_port_t port)
{
return memcached_server_add_with_weight(shell, hostname, port, 0);
}
memcached_return_t memcached_server_add_with_weight(memcached_st *shell,
const char *hostname,
in_port_t port,
uint32_t weight)
{
Memcached* ptr= memcached2Memcached(shell);
if (ptr == NULL)
{
return MEMCACHED_INVALID_ARGUMENTS;
}
if (port == 0)
{
port= MEMCACHED_DEFAULT_PORT;
}
size_t hostname_length= hostname ? strlen(hostname) : 0;
if (hostname_length == 0)
{
hostname= "localhost";
hostname_length= memcached_literal_param_size("localhost");
}
memcached_string_t _hostname= { hostname, hostname_length };
if (memcached_is_valid_servername(_hostname) == false)
{
return memcached_set_error(*ptr, MEMCACHED_INVALID_ARGUMENTS, MEMCACHED_AT, memcached_literal_param("Invalid hostname provided"));
}
return server_add(ptr, _hostname, port, weight, _hostname.c_str[0] == '/' ? MEMCACHED_CONNECTION_UNIX_SOCKET : MEMCACHED_CONNECTION_TCP);
}
memcached_return_t memcached_server_add_parsed(memcached_st *ptr,
const char *hostname,
size_t hostname_length,
in_port_t port,
uint32_t weight)
{
char buffer[MEMCACHED_NI_MAXHOST];
memcpy(buffer, hostname, hostname_length);
buffer[hostname_length]= 0;
memcached_string_t _hostname= { buffer, hostname_length };
return server_add(ptr, _hostname,
port,
weight,
MEMCACHED_CONNECTION_TCP);
}