+/* LibMemcached
+ * Copyright (C) 2006-2009 Brian Aker
+ * All rights reserved.
+ *
+ * Use and distribution licensed under the BSD license. See
+ * the COPYING file in the parent directory for full text.
+ *
+ * Summary: Get functions for libmemcached
+ *
+ */
+
#include "common.h"
#include "memcached_io.h"
-/*
+/*
What happens if no servers exist?
*/
-char *memcached_get(memcached_st *ptr, char *key, size_t key_length,
- size_t *value_length,
+char *memcached_get(memcached_st *ptr, const char *key,
+ size_t key_length,
+ size_t *value_length,
uint32_t *flags,
- memcached_return *error)
+ memcached_return_t *error)
{
- return memcached_get_by_key(ptr, NULL, 0, key, key_length, value_length,
+ return memcached_get_by_key(ptr, NULL, 0, key, key_length, value_length,
flags, error);
}
-char *memcached_get_by_key(memcached_st *ptr,
- char *master_key, size_t master_key_length,
- char *key, size_t key_length,
- size_t *value_length,
+static memcached_return_t memcached_mget_by_key_real(memcached_st *ptr,
+ const char *master_key,
+ size_t master_key_length,
+ const char * const *keys,
+ const size_t *key_length,
+ size_t number_of_keys,
+ bool mget_mode);
+
+char *memcached_get_by_key(memcached_st *ptr,
+ const char *master_key,
+ size_t master_key_length,
+ const char *key, size_t key_length,
+ size_t *value_length,
uint32_t *flags,
- memcached_return *error)
+ memcached_return_t *error)
{
char *value;
size_t dummy_length;
uint32_t dummy_flags;
- memcached_return dummy_error;
+ memcached_return_t dummy_error;
+
+ unlikely (ptr->flags.use_udp)
+ {
+ *error= MEMCACHED_NOT_SUPPORTED;
+ return NULL;
+ }
/* Request the key */
- *error= memcached_mget_by_key(ptr,
- master_key,
- master_key_length,
- &key, &key_length, 1);
+ *error= memcached_mget_by_key_real(ptr, master_key, master_key_length,
+ (const char * const *)&key,
+ &key_length, 1, false);
- value= memcached_fetch(ptr, NULL, NULL,
+ value= memcached_fetch(ptr, NULL, NULL,
value_length, flags, error);
/* This is for historical reasons */
if (*error == MEMCACHED_END)
{
if (ptr->get_key_failure && *error == MEMCACHED_NOTFOUND)
{
- memcached_return rc;
+ memcached_return_t rc;
memcached_result_reset(&ptr->result);
rc= ptr->get_key_failure(ptr, key, key_length, &ptr->result);
-
+
/* On all failure drop to returning NULL */
if (rc == MEMCACHED_SUCCESS || rc == MEMCACHED_BUFFERED)
{
- uint8_t latch; /* We use latch to track the state of the original socket */
-
if (rc == MEMCACHED_BUFFERED)
{
+ uint64_t latch; /* We use latch to track the state of the original socket */
latch= memcached_behavior_get(ptr, MEMCACHED_BEHAVIOR_BUFFER_REQUESTS);
if (latch == 0)
memcached_behavior_set(ptr, MEMCACHED_BEHAVIOR_BUFFER_REQUESTS, 1);
- }
- rc= memcached_set(ptr, key, key_length,
- memcached_result_value(&ptr->result),
- memcached_result_length(&ptr->result),
- 0, memcached_result_flags(&ptr->result));
+ rc= memcached_set(ptr, key, key_length,
+ memcached_result_value(&ptr->result),
+ memcached_result_length(&ptr->result),
+ 0, memcached_result_flags(&ptr->result));
- if (rc == MEMCACHED_BUFFERED && latch == 0)
- memcached_behavior_set(ptr, MEMCACHED_BEHAVIOR_BUFFER_REQUESTS, 0);
+ if (rc == MEMCACHED_BUFFERED && latch == 0)
+ memcached_behavior_set(ptr, MEMCACHED_BEHAVIOR_BUFFER_REQUESTS, 0);
+ }
+ else
+ {
+ rc= memcached_set(ptr, key, key_length,
+ memcached_result_value(&ptr->result),
+ memcached_result_length(&ptr->result),
+ 0, memcached_result_flags(&ptr->result));
+ }
if (rc == MEMCACHED_SUCCESS || rc == MEMCACHED_BUFFERED)
{
return NULL;
}
- (void)memcached_fetch(ptr, NULL, NULL,
- &dummy_length, &dummy_flags,
+ (void)memcached_fetch(ptr, NULL, NULL,
+ &dummy_length, &dummy_flags,
&dummy_error);
WATCHPOINT_ASSERT(dummy_length == 0);
return value;
}
-memcached_return memcached_mget(memcached_st *ptr,
- char **keys, size_t *key_length,
- unsigned int number_of_keys)
+memcached_return_t memcached_mget(memcached_st *ptr,
+ const char * const *keys,
+ const size_t *key_length,
+ size_t number_of_keys)
{
return memcached_mget_by_key(ptr, NULL, 0, keys, key_length, number_of_keys);
}
-memcached_return memcached_mget_by_key(memcached_st *ptr,
- char *master_key, size_t master_key_length,
- char **keys, size_t *key_length,
- unsigned int number_of_keys)
+static memcached_return_t binary_mget_by_key(memcached_st *ptr,
+ unsigned int master_server_key,
+ bool is_master_key_set,
+ const char * const *keys,
+ const size_t *key_length,
+ size_t number_of_keys,
+ bool mget_mode);
+
+static memcached_return_t memcached_mget_by_key_real(memcached_st *ptr,
+ const char *master_key,
+ size_t master_key_length,
+ const char * const *keys,
+ const size_t *key_length,
+ size_t number_of_keys,
+ bool mget_mode)
{
unsigned int x;
- memcached_return rc= MEMCACHED_NOTFOUND;
- char *get_command= "get ";
+ memcached_return_t rc= MEMCACHED_NOTFOUND;
+ const char *get_command= "get ";
uint8_t get_command_length= 4;
- unsigned int master_server_key= 0;
+ unsigned int master_server_key= (unsigned int)-1; /* 0 is a valid server id! */
+ bool is_master_key_set= false;
+
+ unlikely (ptr->flags.use_udp)
+ return MEMCACHED_NOT_SUPPORTED;
LIBMEMCACHED_MEMCACHED_MGET_START();
ptr->cursor_server= 0;
if (ptr->number_of_hosts == 0)
return MEMCACHED_NO_SERVERS;
- if ((ptr->flags & MEM_VERIFY_KEY) && (memcachd_key_test(keys, key_length, number_of_keys) == MEMCACHED_BAD_KEY_PROVIDED))
+ if (ptr->flags.verify_key && (memcached_key_test(keys, key_length, number_of_keys) == MEMCACHED_BAD_KEY_PROVIDED))
return MEMCACHED_BAD_KEY_PROVIDED;
- if (ptr->flags & MEM_SUPPORT_CAS)
- {
- get_command= "gets ";
- get_command_length= 5;
- }
-
if (master_key && master_key_length)
+ {
+ if (ptr->flags.verify_key && (memcached_key_test((const char * const *)&master_key, &master_key_length, 1) == MEMCACHED_BAD_KEY_PROVIDED))
+ return MEMCACHED_BAD_KEY_PROVIDED;
master_server_key= memcached_generate_hash(ptr, master_key, master_key_length);
+ is_master_key_set= true;
+ }
- /*
+ /*
Here is where we pay for the non-block API. We need to remove any data sitting
in the queue before we start our get.
{
char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
- if (ptr->flags & MEM_NO_BLOCK)
+ if (ptr->flags.no_block)
(void)memcached_io_write(&ptr->hosts[x], NULL, 0, 1);
while(memcached_server_response_count(&ptr->hosts[x]))
}
}
- /*
+ if (ptr->flags.binary_protocol)
+ return binary_mget_by_key(ptr, master_server_key, is_master_key_set, keys,
+ key_length, number_of_keys, mget_mode);
+
+ if (ptr->flags.support_cas)
+ {
+ get_command= "gets ";
+ get_command_length= 5;
+ }
+
+ /*
If a server fails we warn about errors and start all over with sending keys
to the server.
*/
{
unsigned int server_key;
- if (master_server_key)
+ if (is_master_key_set)
server_key= master_server_key;
else
server_key= memcached_generate_hash(ptr, keys[x], key_length[x]);
WATCHPOINT_ASSERT(ptr->hosts[server_key].cursor_active == 1);
}
+ /* Only called when we have a prefix key */
+ if (ptr->prefix_key[0] != 0)
+ {
+ if ((memcached_io_write(&ptr->hosts[server_key], ptr->prefix_key, ptr->prefix_key_length, 0)) == -1)
+ {
+ memcached_server_response_reset(&ptr->hosts[server_key]);
+ rc= MEMCACHED_SOME_ERRORS;
+ continue;
+ }
+ }
+
if ((memcached_io_write(&ptr->hosts[server_key], keys[x], key_length[x], 0)) == -1)
{
memcached_server_response_reset(&ptr->hosts[server_key]);
LIBMEMCACHED_MEMCACHED_MGET_END();
return rc;
}
+
+memcached_return_t memcached_mget_by_key(memcached_st *ptr,
+ const char *master_key,
+ size_t master_key_length,
+ const char * const *keys,
+ const size_t *key_length,
+ size_t number_of_keys)
+{
+ return memcached_mget_by_key_real(ptr, master_key, master_key_length, keys,
+ key_length, number_of_keys, true);
+}
+
+memcached_return_t memcached_mget_execute(memcached_st *ptr,
+ const char * const *keys,
+ const size_t *key_length,
+ size_t number_of_keys,
+ memcached_execute_fn *callback,
+ void *context,
+ unsigned int number_of_callbacks)
+{
+ return memcached_mget_execute_by_key(ptr, NULL, 0, keys, key_length,
+ number_of_keys, callback,
+ context, number_of_callbacks);
+}
+
+memcached_return_t memcached_mget_execute_by_key(memcached_st *ptr,
+ const char *master_key,
+ size_t master_key_length,
+ const char * const *keys,
+ const size_t *key_length,
+ size_t number_of_keys,
+ memcached_execute_fn *callback,
+ void *context,
+ unsigned int number_of_callbacks)
+{
+ if ((ptr->flags.binary_protocol) == 0)
+ return MEMCACHED_NOT_SUPPORTED;
+
+ memcached_return_t rc;
+ memcached_callback_st *original_callbacks= ptr->callbacks;
+ memcached_callback_st cb= {
+ .callback= callback,
+ .context= context,
+ .number_of_callback= number_of_callbacks
+ };
+
+ ptr->callbacks= &cb;
+ rc= memcached_mget_by_key(ptr, master_key, master_key_length, keys,
+ key_length, number_of_keys);
+ ptr->callbacks= original_callbacks;
+ return rc;
+}
+
+static memcached_return_t simple_binary_mget(memcached_st *ptr,
+ unsigned int master_server_key,
+ bool is_master_key_set,
+ const char * const *keys,
+ const size_t *key_length,
+ size_t number_of_keys, bool mget_mode)
+{
+ memcached_return_t rc= MEMCACHED_NOTFOUND;
+ uint32_t x;
+
+ int flush= number_of_keys == 1;
+
+ /*
+ If a server fails we warn about errors and start all over with sending keys
+ to the server.
+ */
+ for (x= 0; x < number_of_keys; x++)
+ {
+ unsigned int server_key;
+
+ if (is_master_key_set)
+ server_key= master_server_key;
+ else
+ server_key= memcached_generate_hash(ptr, keys[x], key_length[x]);
+
+ if (memcached_server_response_count(&ptr->hosts[server_key]) == 0)
+ {
+ rc= memcached_connect(&ptr->hosts[server_key]);
+ if (rc != MEMCACHED_SUCCESS)
+ continue;
+ }
+
+ protocol_binary_request_getk request= {.bytes= {0}};
+ request.message.header.request.magic= PROTOCOL_BINARY_REQ;
+ if (mget_mode)
+ request.message.header.request.opcode= PROTOCOL_BINARY_CMD_GETKQ;
+ else
+ request.message.header.request.opcode= PROTOCOL_BINARY_CMD_GETK;
+
+ memcached_return_t vk;
+ vk= memcached_validate_key_length(key_length[x],
+ ptr->flags.binary_protocol);
+ unlikely (vk != MEMCACHED_SUCCESS)
+ {
+ if (x > 0)
+ memcached_io_reset(&ptr->hosts[server_key]);
+ return vk;
+ }
+
+ request.message.header.request.keylen= htons((uint16_t)key_length[x]);
+ request.message.header.request.datatype= PROTOCOL_BINARY_RAW_BYTES;
+ request.message.header.request.bodylen= htonl((uint32_t) key_length[x]);
+
+ if ((memcached_io_write(&ptr->hosts[server_key], request.bytes,
+ sizeof(request.bytes), 0) == -1) ||
+ (memcached_io_write(&ptr->hosts[server_key], keys[x],
+ key_length[x], (char) flush) == -1))
+ {
+ memcached_server_response_reset(&ptr->hosts[server_key]);
+ rc= MEMCACHED_SOME_ERRORS;
+ continue;
+ }
+
+ /* We just want one pending response per server */
+ memcached_server_response_reset(&ptr->hosts[server_key]);
+ memcached_server_response_increment(&ptr->hosts[server_key]);
+ if ((x > 0 && x == ptr->io_key_prefetch) &&
+ memcached_flush_buffers(ptr) != MEMCACHED_SUCCESS)
+ rc= MEMCACHED_SOME_ERRORS;
+ }
+
+ if (mget_mode)
+ {
+ /*
+ * Send a noop command to flush the buffers
+ */
+ protocol_binary_request_noop request= {.bytes= {0}};
+ request.message.header.request.magic= PROTOCOL_BINARY_REQ;
+ request.message.header.request.opcode= PROTOCOL_BINARY_CMD_NOOP;
+ request.message.header.request.datatype= PROTOCOL_BINARY_RAW_BYTES;
+
+ for (x= 0; x < ptr->number_of_hosts; x++)
+ if (memcached_server_response_count(&ptr->hosts[x]))
+ {
+ if (memcached_io_write(&ptr->hosts[x], NULL, 0, 1) == -1)
+ {
+ memcached_server_response_reset(&ptr->hosts[x]);
+ memcached_io_reset(&ptr->hosts[x]);
+ rc= MEMCACHED_SOME_ERRORS;
+ }
+
+ if (memcached_io_write(&ptr->hosts[x], request.bytes,
+ sizeof(request.bytes), 1) == -1)
+ {
+ memcached_server_response_reset(&ptr->hosts[x]);
+ memcached_io_reset(&ptr->hosts[x]);
+ rc= MEMCACHED_SOME_ERRORS;
+ }
+ }
+ }
+
+
+ return rc;
+}
+
+static memcached_return_t replication_binary_mget(memcached_st *ptr,
+ uint32_t* hash,
+ bool* dead_servers,
+ const char *const *keys,
+ const size_t *key_length,
+ size_t number_of_keys)
+{
+ memcached_return_t rc= MEMCACHED_NOTFOUND;
+ uint32_t x, start= 0;
+ uint64_t randomize_read= memcached_behavior_get(ptr, MEMCACHED_BEHAVIOR_RANDOMIZE_REPLICA_READ);
+
+ if (randomize_read)
+ start= (uint32_t)random() % (uint32_t)(ptr->number_of_replicas + 1);
+
+ /* Loop for each replica */
+ for (uint32_t replica= 0; replica <= ptr->number_of_replicas; ++replica)
+ {
+ bool success= true;
+
+ for (x= 0; x < number_of_keys; ++x)
+ {
+ if (hash[x] == ptr->number_of_hosts)
+ continue; /* Already successfully sent */
+
+ uint32_t server= hash[x] + replica;
+
+ /* In case of randomized reads */
+ if (randomize_read && ((server + start) <= (hash[x] + ptr->number_of_replicas)))
+ server += start;
+
+ while (server >= ptr->number_of_hosts)
+ server -= ptr->number_of_hosts;
+
+ if (dead_servers[server])
+ continue;
+
+ if (memcached_server_response_count(&ptr->hosts[server]) == 0)
+ {
+ rc= memcached_connect(&ptr->hosts[server]);
+ if (rc != MEMCACHED_SUCCESS)
+ {
+ memcached_io_reset(&ptr->hosts[server]);
+ dead_servers[server]= true;
+ success= false;
+ continue;
+ }
+ }
+
+ protocol_binary_request_getk request= {
+ .message.header.request= {
+ .magic= PROTOCOL_BINARY_REQ,
+ .opcode= PROTOCOL_BINARY_CMD_GETK,
+ .keylen= htons((uint16_t)key_length[x]),
+ .datatype= PROTOCOL_BINARY_RAW_BYTES,
+ .bodylen= htonl((uint32_t)key_length[x])
+ }
+ };
+
+ /*
+ * We need to disable buffering to actually know that the request was
+ * successfully sent to the server (so that we should expect a result
+ * back). It would be nice to do this in buffered mode, but then it
+ * would be complex to handle all error situations if we got to send
+ * some of the messages, and then we failed on writing out some others
+ * and we used the callback interface from memcached_mget_execute so
+ * that we might have processed some of the responses etc. For now,
+ * just make sure we work _correctly_
+ */
+ if ((memcached_io_write(&ptr->hosts[server], request.bytes,
+ sizeof(request.bytes), 0) == -1) ||
+ (memcached_io_write(&ptr->hosts[server], keys[x],
+ key_length[x], 1) == -1))
+ {
+ memcached_io_reset(&ptr->hosts[server]);
+ dead_servers[server]= true;
+ success= false;
+ continue;
+ }
+
+ memcached_server_response_increment(&ptr->hosts[server]);
+ hash[x]= ptr->number_of_hosts;
+ }
+
+ if (success)
+ break;
+ }
+
+ return rc;
+}
+
+static memcached_return_t binary_mget_by_key(memcached_st *ptr,
+ unsigned int master_server_key,
+ bool is_master_key_set,
+ const char * const *keys,
+ const size_t *key_length,
+ size_t number_of_keys,
+ bool mget_mode)
+{
+ memcached_return_t rc;
+
+ if (ptr->number_of_replicas == 0)
+ {
+ rc= simple_binary_mget(ptr, master_server_key, is_master_key_set,
+ keys, key_length, number_of_keys, mget_mode);
+ }
+ else
+ {
+ uint32_t* hash;
+ bool* dead_servers;
+
+ hash= ptr->call_malloc(ptr, sizeof(uint32_t) * number_of_keys);
+ dead_servers= ptr->call_calloc(ptr, ptr->number_of_hosts, sizeof(bool));
+
+ if (hash == NULL || dead_servers == NULL)
+ {
+ ptr->call_free(ptr, hash);
+ ptr->call_free(ptr, dead_servers);
+ return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
+ }
+
+ if (is_master_key_set)
+ for (unsigned int x= 0; x < number_of_keys; x++)
+ hash[x]= master_server_key;
+ else
+ for (unsigned int x= 0; x < number_of_keys; x++)
+ hash[x]= memcached_generate_hash(ptr, keys[x], key_length[x]);
+
+ rc= replication_binary_mget(ptr, hash, dead_servers, keys,
+ key_length, number_of_keys);
+
+ ptr->call_free(ptr, hash);
+ ptr->call_free(ptr, dead_servers);
+
+ return MEMCACHED_SUCCESS;
+ }
+
+ return rc;
+}