1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
|
/*
* nghttp2 - HTTP/2 C Library
*
* Copyright (c) 2015 Tatsuhiro Tsujikawa
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#ifndef SHRPX_MEMCACHED_CONNECTION_H
#define SHRPX_MEMCACHED_CONNECTION_H
#include "shrpx.h"
#include <memory>
#include <deque>
#include <ev.h>
#include "shrpx_connection.h"
#include "shrpx_tls.h"
#include "shrpx_connect_blocker.h"
#include "buffer.h"
#include "network.h"
using namespace nghttp2;
namespace shrpx {
struct MemcachedRequest;
enum class MemcachedOp : uint8_t;
enum class MemcachedStatusCode : uint16_t;
enum class MemcachedParseState {
HEADER24,
EXTRA,
VALUE,
};
// Stores state when parsing response from memcached server
struct MemcachedParseContext {
// Buffer for value, dynamically allocated.
std::vector<uint8_t> value;
// cas in response
uint64_t cas;
// keylen in response
size_t keylen;
// extralen in response
size_t extralen;
// totalbody in response. The length of value is totalbody -
// extralen - keylen.
size_t totalbody;
// Number of bytes left to read variable length field.
size_t read_left;
// Parser state; see enum above
MemcachedParseState state;
// status_code in response
MemcachedStatusCode status_code;
// op in response
MemcachedOp op;
};
struct MemcachedSendbuf {
// Buffer for header + extra + key
Buffer<512> headbuf;
// MemcachedRequest associated to this object
MemcachedRequest *req;
// Number of bytes left when sending value
size_t send_value_left;
// Returns the number of bytes this object transmits.
size_t left() const { return headbuf.rleft() + send_value_left; }
};
constexpr uint8_t MEMCACHED_REQ_MAGIC = 0x80;
constexpr uint8_t MEMCACHED_RES_MAGIC = 0x81;
// MemcachedConnection implements part of memcached binary protocol.
// This is not full brown implementation. Just the part we need is
// implemented. We only use GET and ADD.
//
// https://github.com/memcached/memcached/blob/master/doc/protocol-binary.xml
// https://code.google.com/p/memcached/wiki/MemcacheBinaryProtocol
class MemcachedConnection {
public:
MemcachedConnection(const Address *addr, struct ev_loop *loop,
SSL_CTX *ssl_ctx, const StringRef &sni_name,
MemchunkPool *mcpool, std::mt19937 &gen);
~MemcachedConnection();
void disconnect();
int add_request(std::unique_ptr<MemcachedRequest> req);
int initiate_connection();
int connected();
int on_write();
int on_read();
int write_clear();
int read_clear();
int tls_handshake();
int write_tls();
int read_tls();
size_t fill_request_buffer(struct iovec *iov, size_t iovlen);
void drain_send_queue(size_t nwrite);
void make_request(MemcachedSendbuf *sendbuf, MemcachedRequest *req);
int parse_packet();
size_t serialized_size(MemcachedRequest *req);
void signal_write();
int noop();
void reconnect_or_fail();
private:
Connection conn_;
std::deque<std::unique_ptr<MemcachedRequest>> recvq_;
std::deque<std::unique_ptr<MemcachedRequest>> sendq_;
std::deque<MemcachedSendbuf> sendbufv_;
std::function<int(MemcachedConnection &)> do_read_, do_write_;
StringRef sni_name_;
tls::TLSSessionCache tls_session_cache_;
ConnectBlocker connect_blocker_;
MemcachedParseContext parse_state_;
const Address *addr_;
SSL_CTX *ssl_ctx_;
// Sum of the bytes to be transmitted in sendbufv_.
size_t sendsum_;
size_t try_count_;
bool connected_;
Buffer<8_k> recvbuf_;
};
} // namespace shrpx
#endif // SHRPX_MEMCACHED_CONNECTION_H
|
