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
|
/**
* Copyright (C) 2014 MongoDB Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the GNU Affero General Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#include "mongo/platform/basic.h"
#include "mongo/util/signal_handlers.h"
#include <boost/thread.hpp>
#include <signal.h>
#if !defined(_WIN32)
#include <unistd.h>
#endif
#include "mongo/db/client.h"
#include "mongo/db/log_process_details.h"
#include "mongo/db/server_options.h"
#include "mongo/platform/process_id.h"
#include "mongo/util/assert_util.h"
#include "mongo/util/exit_code.h"
#include "mongo/util/log.h"
#include "mongo/util/quick_exit.h"
#include "mongo/util/scopeguard.h"
#include "mongo/util/signal_handlers_synchronous.h"
#include "mongo/util/signal_win32.h"
#if defined(_WIN32)
namespace {
const char* strsignal(int signalNum) {
// should only see SIGABRT on windows
switch (signalNum) {
case SIGABRT: return "SIGABRT";
default: return "UNKNOWN";
}
}
}
#endif
namespace mongo {
/*
* WARNING: PLEASE READ BEFORE CHANGING THIS MODULE
*
* All code in this module must be signal-friendly. Before adding any system
* call or other dependency, please make sure that this still holds.
*
* All code in this file follows this pattern:
* Generic code
* #ifdef _WIN32
* Windows code
* #else
* Posix code
* #endif
*
*/
namespace {
#ifdef _WIN32
void consoleTerminate( const char* controlCodeName ) {
Client::initThread( "consoleTerminate" );
log() << "got " << controlCodeName << ", will terminate after current cmd ends" << endl;
exitCleanly( EXIT_KILL );
}
BOOL WINAPI CtrlHandler( DWORD fdwCtrlType ) {
switch( fdwCtrlType ) {
case CTRL_C_EVENT:
log() << "Ctrl-C signal";
consoleTerminate( "CTRL_C_EVENT" );
return TRUE ;
case CTRL_CLOSE_EVENT:
log() << "CTRL_CLOSE_EVENT signal";
consoleTerminate( "CTRL_CLOSE_EVENT" );
return TRUE ;
case CTRL_BREAK_EVENT:
log() << "CTRL_BREAK_EVENT signal";
consoleTerminate( "CTRL_BREAK_EVENT" );
return TRUE;
case CTRL_LOGOFF_EVENT:
// only sent to services, and only in pre-Vista Windows; FALSE means ignore
return FALSE;
case CTRL_SHUTDOWN_EVENT:
log() << "CTRL_SHUTDOWN_EVENT signal";
consoleTerminate( "CTRL_SHUTDOWN_EVENT" );
return TRUE;
default:
return FALSE;
}
}
void eventProcessingThread() {
std::string eventName = getShutdownSignalName(ProcessId::getCurrent().asUInt32());
HANDLE event = CreateEventA(NULL, TRUE, FALSE, eventName.c_str());
if (event == NULL) {
warning() << "eventProcessingThread CreateEvent failed: "
<< errnoWithDescription();
return;
}
ON_BLOCK_EXIT(CloseHandle, event);
int returnCode = WaitForSingleObject(event, INFINITE);
if (returnCode != WAIT_OBJECT_0) {
if (returnCode == WAIT_FAILED) {
warning() << "eventProcessingThread WaitForSingleObject failed: "
<< errnoWithDescription();
return;
}
else {
warning() << "eventProcessingThread WaitForSingleObject failed: "
<< errnoWithDescription(returnCode);
return;
}
}
Client::initThread("eventTerminate");
log() << "shutdown event signaled, will terminate after current cmd ends";
exitCleanly(EXIT_CLEAN);
}
#else
// The signals in asyncSignals will be processed by this thread only, in order to
// ensure the db and log mutexes aren't held. Because this is run in a different thread, it does
// not need to be safe to call in signal context.
sigset_t asyncSignals;
void signalProcessingThread() {
Client::initThread( "signalProcessingThread" );
while (true) {
int actualSignal = 0;
int status = sigwait( &asyncSignals, &actualSignal );
fassert(16781, status == 0);
switch (actualSignal) {
case SIGUSR1:
// log rotate signal
fassert(16782, rotateLogs(serverGlobalParams.logRenameOnRotate));
logProcessDetailsForLogRotate();
break;
case SIGQUIT:
log() << "Received SIGQUIT; terminating.";
quickExit(EXIT_ABRUPT);
default:
// interrupt/terminate signal
log() << "got signal " << actualSignal << " (" << strsignal( actualSignal )
<< "), will terminate after current cmd ends" << endl;
exitCleanly( EXIT_CLEAN );
break;
}
}
}
#endif
} // namespace
void setupSignalHandlers(bool handleControlC) {
setupSynchronousSignalHandlers();
#ifdef _WIN32
if (!handleControlC) {
massert(10297,
"Couldn't register Windows Ctrl-C handler",
SetConsoleCtrlHandler(static_cast<PHANDLER_ROUTINE>(CtrlHandler), TRUE));
}
#else
// asyncSignals is a global variable listing the signals that should be handled by the
// interrupt thread, once it is started via startSignalProcessingThread().
sigemptyset( &asyncSignals );
sigaddset( &asyncSignals, SIGHUP );
if (!handleControlC) {
sigaddset( &asyncSignals, SIGINT );
}
sigaddset( &asyncSignals, SIGTERM );
sigaddset( &asyncSignals, SIGQUIT );
sigaddset( &asyncSignals, SIGUSR1 );
sigaddset( &asyncSignals, SIGXCPU );
#endif
}
void startSignalProcessingThread() {
#ifdef _WIN32
boost::thread(eventProcessingThread).detach();
#else
// Mask signals in the current (only) thread. All new threads will inherit this mask.
invariant( pthread_sigmask( SIG_SETMASK, &asyncSignals, 0 ) == 0 );
// Spawn a thread to capture the signals we just masked off.
boost::thread( signalProcessingThread ).detach();
#endif
}
} // namespace mongo
|