2 +--------------------------------------------------------------------+
3 | libmemcached-awesome - 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) 2020-2021 Michael Wallner https://awesome.co/ |
13 +--------------------------------------------------------------------+
16 #include "libmemcached/common.h"
19 * The udp request id consists of two seperate sections
21 * 2) The message number
22 * The thread id should only be set when the memcached_st struct is created
23 * and should not be changed.
25 * The message num is incremented for each new message we send, this function
26 * extracts the message number from message_id, increments it and then
27 * writes the new value back into the header
29 void increment_udp_message_id(memcached_instance_st
*ptr
) {
30 struct udp_datagram_header_st
*header
= (struct udp_datagram_header_st
*) ptr
->write_buffer
;
31 uint16_t cur_req
= get_udp_datagram_request_id(header
);
32 int msg_num
= get_msg_num_from_request_id(cur_req
);
33 int thread_id
= get_thread_id_from_request_id(cur_req
);
35 if (((++msg_num
) & UDP_REQUEST_ID_THREAD_MASK
))
38 header
->request_id
= htons((uint16_t)(thread_id
| msg_num
));
41 bool memcached_io_init_udp_header(memcached_instance_st
*ptr
, const uint16_t thread_id
) {
42 if (thread_id
> UDP_REQUEST_ID_MAX_THREAD_ID
) {
43 return MEMCACHED_FAILURE
;
46 struct udp_datagram_header_st
*header
= (struct udp_datagram_header_st
*) ptr
->write_buffer
;
47 header
->request_id
= htons(uint16_t((generate_udp_request_thread_id(thread_id
))));
48 header
->num_datagrams
= htons(1);
49 header
->sequence_number
= htons(0);
51 return MEMCACHED_SUCCESS
;