2 +--------------------------------------------------------------------+
3 | libmemcached - C/C++ Client Library for memcached |
4 +--------------------------------------------------------------------+
5 | Redistribution and use in source and binary forms, with or without |
6 | modification, are permitted under the terms of the BSD license. |
7 | You should have received a copy of the license in a bundled file |
8 | named LICENSE; in case you did not receive a copy you can review |
9 | the terms online at: https://opensource.org/licenses/BSD-3-Clause |
10 +--------------------------------------------------------------------+
11 | Copyright (c) 2006-2014 Brian Aker https://datadifferential.com/ |
12 | Copyright (c) 2020 Michael Wallner <mike@php.net> |
13 +--------------------------------------------------------------------+
16 #include "libmemcached/common.h"
18 char *memcached_get(memcached_st
*ptr
, const char *key
, size_t key_length
, size_t *value_length
,
19 uint32_t *flags
, memcached_return_t
*error
) {
20 return memcached_get_by_key(ptr
, NULL
, 0, key
, key_length
, value_length
, flags
, error
);
23 static memcached_return_t
__mget_by_key_real(memcached_st
*ptr
, const char *group_key
,
24 size_t group_key_length
, const char *const *keys
,
25 const size_t *key_length
, size_t number_of_keys
,
26 const bool mget_mode
);
27 char *memcached_get_by_key(memcached_st
*shell
, const char *group_key
, size_t group_key_length
,
28 const char *key
, size_t key_length
, size_t *value_length
,
29 uint32_t *flags
, memcached_return_t
*error
) {
30 Memcached
*ptr
= memcached2Memcached(shell
);
31 memcached_return_t unused
;
36 uint64_t query_id
= 0;
38 query_id
= ptr
->query_id
;
42 *error
= __mget_by_key_real(ptr
, group_key
, group_key_length
, (const char *const *) &key
,
43 &key_length
, 1, false);
45 assert_msg(ptr
->query_id
== query_id
+ 1,
46 "Programmer error, the query_id was not incremented.");
49 if (memcached_failed(*error
)) {
51 if (memcached_has_current_error(*ptr
)) // Find the most accurate error
53 *error
= memcached_last_error(ptr
);
64 char *value
= memcached_fetch(ptr
, NULL
, NULL
, value_length
, flags
, error
);
65 assert_msg(ptr
->query_id
== query_id
+ 1, "Programmer error, the query_id was not incremented.");
67 /* This is for historical reasons */
68 if (*error
== MEMCACHED_END
) {
69 *error
= MEMCACHED_NOTFOUND
;
72 if (ptr
->get_key_failure
and *error
== MEMCACHED_NOTFOUND
) {
73 memcached_result_st key_failure_result
;
74 memcached_result_st
*result_ptr
= memcached_result_create(ptr
, &key_failure_result
);
75 memcached_return_t rc
= ptr
->get_key_failure(ptr
, key
, key_length
, result_ptr
);
77 /* On all failure drop to returning NULL */
78 if (rc
== MEMCACHED_SUCCESS
or rc
== MEMCACHED_BUFFERED
) {
79 if (rc
== MEMCACHED_BUFFERED
) {
80 uint64_t latch
; /* We use latch to track the state of the original socket */
81 latch
= memcached_behavior_get(ptr
, MEMCACHED_BEHAVIOR_BUFFER_REQUESTS
);
83 memcached_behavior_set(ptr
, MEMCACHED_BEHAVIOR_BUFFER_REQUESTS
, 1);
86 rc
= memcached_set(ptr
, key
, key_length
, (memcached_result_value(result_ptr
)),
87 (memcached_result_length(result_ptr
)), 0,
88 (memcached_result_flags(result_ptr
)));
90 if (rc
== MEMCACHED_BUFFERED
and latch
== 0) {
91 memcached_behavior_set(ptr
, MEMCACHED_BEHAVIOR_BUFFER_REQUESTS
, 0);
94 rc
= memcached_set(ptr
, key
, key_length
, (memcached_result_value(result_ptr
)),
95 (memcached_result_length(result_ptr
)), 0,
96 (memcached_result_flags(result_ptr
)));
99 if (rc
== MEMCACHED_SUCCESS
or rc
== MEMCACHED_BUFFERED
) {
101 *value_length
= memcached_result_length(result_ptr
);
102 *flags
= memcached_result_flags(result_ptr
);
103 char *result_value
= memcached_string_take_value(&result_ptr
->value
);
104 memcached_result_free(result_ptr
);
110 memcached_result_free(result_ptr
);
112 assert_msg(ptr
->query_id
== query_id
+ 1,
113 "Programmer error, the query_id was not incremented.");
121 memcached_return_t
memcached_mget(memcached_st
*ptr
, const char *const *keys
,
122 const size_t *key_length
, size_t number_of_keys
) {
123 return memcached_mget_by_key(ptr
, NULL
, 0, keys
, key_length
, number_of_keys
);
126 static memcached_return_t
binary_mget_by_key(memcached_st
*ptr
, const uint32_t master_server_key
,
127 const bool is_group_key_set
, const char *const *keys
,
128 const size_t *key_length
, const size_t number_of_keys
,
129 const bool mget_mode
);
131 static memcached_return_t
__mget_by_key_real(memcached_st
*ptr
, const char *group_key
,
132 const size_t group_key_length
, const char *const *keys
,
133 const size_t *key_length
, size_t number_of_keys
,
134 const bool mget_mode
) {
135 bool failures_occured_in_sending
= false;
136 const char *get_command
= "get";
137 uint8_t get_command_length
= 3;
138 unsigned int master_server_key
= (unsigned int) -1; /* 0 is a valid server id! */
140 memcached_return_t rc
;
141 if (memcached_failed(rc
= initialize_query(ptr
, true))) {
145 if (memcached_is_udp(ptr
)) {
146 return memcached_set_error(*ptr
, MEMCACHED_NOT_SUPPORTED
, MEMCACHED_AT
);
149 LIBMEMCACHED_MEMCACHED_MGET_START();
151 if (number_of_keys
== 0) {
152 return memcached_set_error(*ptr
, MEMCACHED_INVALID_ARGUMENTS
, MEMCACHED_AT
,
153 memcached_literal_param("Numbers of keys provided was zero"));
156 if (memcached_failed((rc
= memcached_key_test(*ptr
, keys
, key_length
, number_of_keys
)))) {
157 assert(memcached_last_error(ptr
) == rc
);
162 bool is_group_key_set
= false;
163 if (group_key
and group_key_length
) {
165 memcached_generate_hash_with_redistribution(ptr
, group_key
, group_key_length
);
166 is_group_key_set
= true;
170 Here is where we pay for the non-block API. We need to remove any data sitting
171 in the queue before we start our get.
173 It might be optimum to bounce the connection if count > some number.
175 for (uint32_t x
= 0; x
< memcached_server_count(ptr
); x
++) {
176 memcached_instance_st
*instance
= memcached_instance_fetch(ptr
, x
);
178 if (instance
->response_count()) {
179 char buffer
[MEMCACHED_DEFAULT_COMMAND_SIZE
];
181 if (ptr
->flags
.no_block
) {
182 memcached_io_write(instance
);
185 while (instance
->response_count()) {
186 (void) memcached_response(instance
, buffer
, MEMCACHED_DEFAULT_COMMAND_SIZE
, &ptr
->result
);
191 if (memcached_is_binary(ptr
)) {
192 return binary_mget_by_key(ptr
, master_server_key
, is_group_key_set
, keys
, key_length
,
193 number_of_keys
, mget_mode
);
196 if (ptr
->flags
.support_cas
) {
197 get_command
= "gets";
198 get_command_length
= 4;
202 If a server fails we warn about errors and start all over with sending keys
205 WATCHPOINT_ASSERT(rc
== MEMCACHED_SUCCESS
);
206 size_t hosts_connected
= 0;
207 for (uint32_t x
= 0; x
< number_of_keys
; x
++) {
210 if (is_group_key_set
) {
211 server_key
= master_server_key
;
213 server_key
= memcached_generate_hash_with_redistribution(ptr
, keys
[x
], key_length
[x
]);
216 memcached_instance_st
*instance
= memcached_instance_fetch(ptr
, server_key
);
218 libmemcached_io_vector_st vector
[] = {
219 {get_command
, get_command_length
},
220 {memcached_literal_param(" ")},
221 {memcached_array_string(ptr
->_namespace
), memcached_array_size(ptr
->_namespace
)},
222 {keys
[x
], key_length
[x
]}};
224 if (instance
->response_count() == 0) {
225 rc
= memcached_connect(instance
);
227 if (memcached_failed(rc
)) {
228 memcached_set_error(*instance
, rc
, MEMCACHED_AT
);
233 if ((memcached_io_writev(instance
, vector
, 1, false)) == false) {
234 failures_occured_in_sending
= true;
237 WATCHPOINT_ASSERT(instance
->cursor_active_
== 0);
238 memcached_instance_response_increment(instance
);
239 WATCHPOINT_ASSERT(instance
->cursor_active_
== 1);
243 if ((memcached_io_writev(instance
, (vector
+ 1), 3, false)) == false) {
244 memcached_instance_response_reset(instance
);
245 failures_occured_in_sending
= true;
251 if (hosts_connected
== 0) {
252 LIBMEMCACHED_MEMCACHED_MGET_END();
254 if (memcached_failed(rc
)) {
258 return memcached_set_error(*ptr
, MEMCACHED_NO_SERVERS
, MEMCACHED_AT
);
262 Should we muddle on if some servers are dead?
264 bool success_happened
= false;
265 for (uint32_t x
= 0; x
< memcached_server_count(ptr
); x
++) {
266 memcached_instance_st
*instance
= memcached_instance_fetch(ptr
, x
);
268 if (instance
->response_count()) {
269 /* We need to do something about non-connnected hosts in the future */
270 if ((memcached_io_write(instance
, "\r\n", 2, true)) == -1) {
271 failures_occured_in_sending
= true;
273 success_happened
= true;
278 LIBMEMCACHED_MEMCACHED_MGET_END();
280 if (failures_occured_in_sending
and success_happened
) {
281 return MEMCACHED_SOME_ERRORS
;
284 if (success_happened
) {
285 return MEMCACHED_SUCCESS
;
288 return MEMCACHED_FAILURE
; // Complete failure occurred
291 memcached_return_t
memcached_mget_by_key(memcached_st
*shell
, const char *group_key
,
292 size_t group_key_length
, const char *const *keys
,
293 const size_t *key_length
, size_t number_of_keys
) {
294 Memcached
*ptr
= memcached2Memcached(shell
);
295 return __mget_by_key_real(ptr
, group_key
, group_key_length
, keys
, key_length
, number_of_keys
,
299 memcached_return_t
memcached_mget_execute(memcached_st
*ptr
, const char *const *keys
,
300 const size_t *key_length
, size_t number_of_keys
,
301 memcached_execute_fn
*callback
, void *context
,
302 unsigned int number_of_callbacks
) {
303 return memcached_mget_execute_by_key(ptr
, NULL
, 0, keys
, key_length
, number_of_keys
, callback
,
304 context
, number_of_callbacks
);
307 memcached_return_t
memcached_mget_execute_by_key(memcached_st
*shell
, const char *group_key
,
308 size_t group_key_length
, const char *const *keys
,
309 const size_t *key_length
, size_t number_of_keys
,
310 memcached_execute_fn
*callback
, void *context
,
311 unsigned int number_of_callbacks
) {
312 Memcached
*ptr
= memcached2Memcached(shell
);
313 memcached_return_t rc
;
314 if (memcached_failed(rc
= initialize_query(ptr
, false))) {
318 if (memcached_is_udp(ptr
)) {
319 return memcached_set_error(*ptr
, MEMCACHED_NOT_SUPPORTED
, MEMCACHED_AT
);
322 if (memcached_is_binary(ptr
) == false) {
323 return memcached_set_error(
324 *ptr
, MEMCACHED_NOT_SUPPORTED
, MEMCACHED_AT
,
325 memcached_literal_param(
326 "ASCII protocol is not supported for memcached_mget_execute_by_key()"));
329 memcached_callback_st
*original_callbacks
= ptr
->callbacks
;
330 memcached_callback_st cb
= {callback
, context
, number_of_callbacks
};
332 ptr
->callbacks
= &cb
;
333 rc
= memcached_mget_by_key(ptr
, group_key
, group_key_length
, keys
, key_length
, number_of_keys
);
334 ptr
->callbacks
= original_callbacks
;
339 static memcached_return_t
simple_binary_mget(memcached_st
*ptr
, const uint32_t master_server_key
,
340 bool is_group_key_set
, const char *const *keys
,
341 const size_t *key_length
, const size_t number_of_keys
,
342 const bool mget_mode
) {
343 memcached_return_t rc
= MEMCACHED_NOTFOUND
;
345 bool flush
= (number_of_keys
== 1);
347 if (memcached_failed(rc
= memcached_key_test(*ptr
, keys
, key_length
, number_of_keys
))) {
352 If a server fails we warn about errors and start all over with sending keys
355 for (uint32_t x
= 0; x
< number_of_keys
; ++x
) {
358 if (is_group_key_set
) {
359 server_key
= master_server_key
;
361 server_key
= memcached_generate_hash_with_redistribution(ptr
, keys
[x
], key_length
[x
]);
364 memcached_instance_st
*instance
= memcached_instance_fetch(ptr
, server_key
);
366 if (instance
->response_count() == 0) {
367 rc
= memcached_connect(instance
);
368 if (memcached_failed(rc
)) {
373 protocol_binary_request_getk request
= {}; //= {.bytes= {0}};
374 initialize_binary_request(instance
, request
.message
.header
);
376 request
.message
.header
.request
.opcode
= PROTOCOL_BINARY_CMD_GETKQ
;
378 request
.message
.header
.request
.opcode
= PROTOCOL_BINARY_CMD_GETK
;
383 memcached_return_t vk
= memcached_validate_key_length(key_length
[x
], ptr
->flags
.binary_protocol
);
384 if (memcached_failed(rc
= memcached_key_test(*memc
, (const char **)&key
, &key_length
, 1)))
386 memcached_set_error(ptr
, vk
, MEMCACHED_AT
, memcached_literal_param("Key was too long."));
390 memcached_io_reset(instance
);
398 request
.message
.header
.request
.keylen
=
399 htons((uint16_t)(key_length
[x
] + memcached_array_size(ptr
->_namespace
)));
400 request
.message
.header
.request
.datatype
= PROTOCOL_BINARY_RAW_BYTES
;
401 request
.message
.header
.request
.bodylen
=
402 htonl((uint32_t)(key_length
[x
] + memcached_array_size(ptr
->_namespace
)));
404 libmemcached_io_vector_st vector
[] = {
405 {request
.bytes
, sizeof(request
.bytes
)},
406 {memcached_array_string(ptr
->_namespace
), memcached_array_size(ptr
->_namespace
)},
407 {keys
[x
], key_length
[x
]}};
409 if (memcached_io_writev(instance
, vector
, 3, flush
) == false) {
410 memcached_server_response_reset(instance
);
411 rc
= MEMCACHED_SOME_ERRORS
;
415 /* We just want one pending response per server */
416 memcached_server_response_reset(instance
);
417 memcached_server_response_increment(instance
);
418 if ((x
> 0 and x
== ptr
->io_key_prefetch
) and memcached_flush_buffers(ptr
) != MEMCACHED_SUCCESS
)
420 rc
= MEMCACHED_SOME_ERRORS
;
426 Send a noop command to flush the buffers
428 protocol_binary_request_noop request
= {}; //= {.bytes= {0}};
429 request
.message
.header
.request
.opcode
= PROTOCOL_BINARY_CMD_NOOP
;
430 request
.message
.header
.request
.datatype
= PROTOCOL_BINARY_RAW_BYTES
;
432 for (uint32_t x
= 0; x
< memcached_server_count(ptr
); ++x
) {
433 memcached_instance_st
*instance
= memcached_instance_fetch(ptr
, x
);
435 if (instance
->response_count()) {
436 initialize_binary_request(instance
, request
.message
.header
);
437 if ((memcached_io_write(instance
) == false)
438 or (memcached_io_write(instance
, request
.bytes
, sizeof(request
.bytes
), true) == -1))
440 memcached_instance_response_reset(instance
);
441 memcached_io_reset(instance
);
442 rc
= MEMCACHED_SOME_ERRORS
;
451 static memcached_return_t
replication_binary_mget(memcached_st
*ptr
, uint32_t *hash
,
452 bool *dead_servers
, const char *const *keys
,
453 const size_t *key_length
,
454 const size_t number_of_keys
) {
455 memcached_return_t rc
= MEMCACHED_NOTFOUND
;
457 uint64_t randomize_read
= memcached_behavior_get(ptr
, MEMCACHED_BEHAVIOR_RANDOMIZE_REPLICA_READ
);
459 if (randomize_read
) {
460 start
= (uint32_t) random() % (uint32_t)(ptr
->number_of_replicas
+ 1);
463 /* Loop for each replica */
464 for (uint32_t replica
= 0; replica
<= ptr
->number_of_replicas
; ++replica
) {
467 for (uint32_t x
= 0; x
< number_of_keys
; ++x
) {
468 if (hash
[x
] == memcached_server_count(ptr
)) {
469 continue; /* Already successfully sent */
472 uint32_t server
= hash
[x
] + replica
;
474 /* In case of randomized reads */
475 if (randomize_read
and ((server
+ start
) <= (hash
[x
] + ptr
->number_of_replicas
))) {
479 while (server
>= memcached_server_count(ptr
)) {
480 server
-= memcached_server_count(ptr
);
483 if (dead_servers
[server
]) {
487 memcached_instance_st
*instance
= memcached_instance_fetch(ptr
, server
);
489 if (instance
->response_count() == 0) {
490 rc
= memcached_connect(instance
);
492 if (memcached_failed(rc
)) {
493 memcached_io_reset(instance
);
494 dead_servers
[server
] = true;
500 protocol_binary_request_getk request
= {};
501 initialize_binary_request(instance
, request
.message
.header
);
502 request
.message
.header
.request
.opcode
= PROTOCOL_BINARY_CMD_GETK
;
503 request
.message
.header
.request
.keylen
=
504 htons((uint16_t)(key_length
[x
] + memcached_array_size(ptr
->_namespace
)));
505 request
.message
.header
.request
.datatype
= PROTOCOL_BINARY_RAW_BYTES
;
506 request
.message
.header
.request
.bodylen
=
507 htonl((uint32_t)(key_length
[x
] + memcached_array_size(ptr
->_namespace
)));
510 * We need to disable buffering to actually know that the request was
511 * successfully sent to the server (so that we should expect a result
512 * back). It would be nice to do this in buffered mode, but then it
513 * would be complex to handle all error situations if we got to send
514 * some of the messages, and then we failed on writing out some others
515 * and we used the callback interface from memcached_mget_execute so
516 * that we might have processed some of the responses etc. For now,
517 * just make sure we work _correctly_
519 libmemcached_io_vector_st vector
[] = {
520 {request
.bytes
, sizeof(request
.bytes
)},
521 {memcached_array_string(ptr
->_namespace
), memcached_array_size(ptr
->_namespace
)},
522 {keys
[x
], key_length
[x
]}};
524 if (memcached_io_writev(instance
, vector
, 3, true) == false) {
525 memcached_io_reset(instance
);
526 dead_servers
[server
] = true;
531 memcached_server_response_increment(instance
);
532 hash
[x
] = memcached_server_count(ptr
);
543 static memcached_return_t
binary_mget_by_key(memcached_st
*ptr
, const uint32_t master_server_key
,
544 bool is_group_key_set
, const char *const *keys
,
545 const size_t *key_length
, const size_t number_of_keys
,
546 const bool mget_mode
) {
547 if (ptr
->number_of_replicas
== 0) {
548 return simple_binary_mget(ptr
, master_server_key
, is_group_key_set
, keys
, key_length
,
549 number_of_keys
, mget_mode
);
552 uint32_t *hash
= libmemcached_xvalloc(ptr
, number_of_keys
, uint32_t);
553 bool *dead_servers
= libmemcached_xcalloc(ptr
, memcached_server_count(ptr
), bool);
555 if (hash
== NULL
or dead_servers
== NULL
) {
556 libmemcached_free(ptr
, hash
);
557 libmemcached_free(ptr
, dead_servers
);
558 return MEMCACHED_MEMORY_ALLOCATION_FAILURE
;
561 if (is_group_key_set
) {
562 for (size_t x
= 0; x
< number_of_keys
; x
++) {
563 hash
[x
] = master_server_key
;
566 for (size_t x
= 0; x
< number_of_keys
; x
++) {
567 hash
[x
] = memcached_generate_hash_with_redistribution(ptr
, keys
[x
], key_length
[x
]);
571 memcached_return_t rc
=
572 replication_binary_mget(ptr
, hash
, dead_servers
, keys
, key_length
, number_of_keys
);
574 WATCHPOINT_IFERROR(rc
);
575 libmemcached_free(ptr
, hash
);
576 libmemcached_free(ptr
, dead_servers
);
578 return MEMCACHED_SUCCESS
;