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
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
|
/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 2001-2009 Oracle. All rights reserved.
*
* $Id$
*/
#include <sys/types.h>
#include <errno.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <db.h>
#include "rep_base.h"
/*
* Process globals (we could put these in the machtab I suppose).
*/
int master_eid;
char *myaddr;
unsigned short myport;
const char *progname = "ex_rep_base";
static void event_callback __P((DB_ENV *, u_int32_t, void *));
int
main(argc, argv)
int argc;
char *argv[];
{
DB_ENV *dbenv;
SETUP_DATA setup_info;
DBT local;
all_args aa;
connect_args ca;
supthr_args supa;
machtab_t *machtab;
thread_t all_thr, ckp_thr, conn_thr, lga_thr;
void *astatus, *cstatus;
#ifdef _WIN32
WSADATA wsaData;
#else
struct sigaction sigact;
#endif
APP_DATA my_app_data;
int ret;
memset(&setup_info, 0, sizeof(SETUP_DATA));
setup_info.progname = progname;
master_eid = DB_EID_INVALID;
memset(&my_app_data, 0, sizeof(APP_DATA));
dbenv = NULL;
machtab = NULL;
ret = 0;
if ((ret = create_env(progname, &dbenv)) != 0)
goto err;
dbenv->app_private = &my_app_data;
(void)dbenv->set_event_notify(dbenv, event_callback);
/* Parse command line and perform common replication setup. */
if ((ret = common_rep_setup(dbenv, argc, argv, &setup_info)) != 0)
goto err;
if (setup_info.role == MASTER)
master_eid = SELF_EID;
myaddr = strdup(setup_info.self.host);
myport = setup_info.self.port;
#ifdef _WIN32
/* Initialize the Windows sockets DLL. */
if ((ret = WSAStartup(MAKEWORD(2, 2), &wsaData)) != 0) {
fprintf(stderr,
"Unable to initialize Windows sockets: %d\n", ret);
goto err;
}
#else
/*
* Turn off SIGPIPE so that we don't kill processes when they
* happen to lose a connection at the wrong time.
*/
memset(&sigact, 0, sizeof(sigact));
sigact.sa_handler = SIG_IGN;
if ((ret = sigaction(SIGPIPE, &sigact, NULL)) != 0) {
fprintf(stderr,
"Unable to turn off SIGPIPE: %s\n", strerror(ret));
goto err;
}
#endif
/*
* We are hardcoding priorities here that all clients have the
* same priority except for a designated master who gets a higher
* priority.
*/
if ((ret =
machtab_init(&machtab, setup_info.nsites)) != 0)
goto err;
my_app_data.comm_infrastructure = machtab;
if ((ret = env_init(dbenv, setup_info.home)) != 0)
goto err;
/*
* Now sets up comm infrastructure. There are two phases. First,
* we open our port for listening for incoming connections. Then
* we attempt to connect to every host we know about.
*/
(void)dbenv->rep_set_transport(dbenv, SELF_EID, quote_send);
ca.dbenv = dbenv;
ca.home = setup_info.home;
ca.progname = progname;
ca.machtab = machtab;
ca.port = setup_info.self.port;
if ((ret = thread_create(&conn_thr, NULL, connect_thread, &ca)) != 0) {
dbenv->errx(dbenv, "can't create connect thread");
goto err;
}
aa.dbenv = dbenv;
aa.progname = progname;
aa.home = setup_info.home;
aa.machtab = machtab;
aa.sites = setup_info.site_list;
aa.nsites = setup_info.remotesites;
if ((ret = thread_create(&all_thr, NULL, connect_all, &aa)) != 0) {
dbenv->errx(dbenv, "can't create connect-all thread");
goto err;
}
/* Start checkpoint and log archive threads. */
supa.dbenv = dbenv;
supa.shared = &my_app_data.shared_data;
if ((ret = start_support_threads(dbenv, &supa, &ckp_thr, &lga_thr))
!= 0)
goto err;
/*
* We have now got the entire communication infrastructure set up.
* It's time to declare ourselves to be a client or master.
*/
if (setup_info.role == MASTER) {
if ((ret = dbenv->rep_start(dbenv, NULL, DB_REP_MASTER)) != 0) {
dbenv->err(dbenv, ret, "dbenv->rep_start failed");
goto err;
}
} else {
memset(&local, 0, sizeof(local));
local.data = myaddr;
local.size = (u_int32_t)strlen(myaddr) + 1;
if ((ret =
dbenv->rep_start(dbenv, &local, DB_REP_CLIENT)) != 0) {
dbenv->err(dbenv, ret, "dbenv->rep_start failed");
goto err;
}
/* Sleep to give ourselves time to find a master. */
sleep(5);
}
if ((ret = doloop(dbenv, &my_app_data.shared_data)) != 0) {
dbenv->err(dbenv, ret, "Main loop failed");
goto err;
}
/* Finish checkpoint and log archive threads. */
if ((ret = finish_support_threads(&ckp_thr, &lga_thr)) != 0)
goto err;
/* Wait on the connection threads. */
if (thread_join(all_thr, &astatus) || thread_join(conn_thr, &cstatus)) {
ret = -1;
goto err;
}
if ((uintptr_t)astatus != EXIT_SUCCESS ||
(uintptr_t)cstatus != EXIT_SUCCESS) {
ret = -1;
goto err;
}
/*
* We have used the DB_TXN_NOSYNC environment flag for improved
* performance without the usual sacrifice of transactional durability,
* as discussed in the "Transactional guarantees" page of the Reference
* Guide: if one replication site crashes, we can expect the data to
* exist at another site. However, in case we shut down all sites
* gracefully, we push out the end of the log here so that the most
* recent transactions don't mysteriously disappear.
*/
if ((ret = dbenv->log_flush(dbenv, NULL)) != 0)
dbenv->err(dbenv, ret, "log_flush");
err: if (machtab != NULL)
free(machtab);
if (dbenv != NULL)
(void)dbenv->close(dbenv, 0);
#ifdef _WIN32
/* Shut down the Windows sockets DLL. */
(void)WSACleanup();
#endif
return (ret);
}
static void
event_callback(dbenv, which, info)
DB_ENV *dbenv;
u_int32_t which;
void *info;
{
APP_DATA *app = dbenv->app_private;
SHARED_DATA *shared = &app->shared_data;
switch (which) {
case DB_EVENT_REP_CLIENT:
shared->is_master = 0;
shared->in_client_sync = 1;
break;
case DB_EVENT_REP_ELECTED:
app->elected = 1;
master_eid = SELF_EID;
break;
case DB_EVENT_REP_MASTER:
shared->is_master = 1;
shared->in_client_sync = 0;
break;
case DB_EVENT_REP_NEWMASTER:
master_eid = *(int*)info;
shared->in_client_sync = 1;
break;
case DB_EVENT_REP_STARTUPDONE:
shared->in_client_sync = 0;
break;
default:
dbenv->errx(dbenv, "ignoring event %d", which);
}
}
|
