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
|
// debug_util.cpp
/* Copyright 2009 10gen 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/debugger.h"
#include "mongo/db/server_options.h"
#include "mongo/util/debug_util.h"
#ifndef _WIN32
#include <signal.h>
#endif
namespace mongo {
void breakpoint() {
#ifdef _WIN32
DEV DebugBreak();
#endif
#ifndef _WIN32
// code to raise a breakpoint in GDB
ONCE {
//prevent SIGTRAP from crashing the program if default action is specified and we are not in gdb
struct sigaction current;
sigaction(SIGTRAP, NULL, ¤t);
if (current.sa_handler == SIG_DFL) {
signal(SIGTRAP, SIG_IGN);
}
}
raise(SIGTRAP);
#endif
}
#if defined(USE_GDBSERVER)
/* Magic gdb trampoline
* Do not call directly! call setupSIGTRAPforGDB()
* Assumptions:
* 1) gdbserver is on your path
* 2) You have run "handle SIGSTOP noprint" in gdb
* 3) serverGlobalParams.port + 2000 is free
*/
void launchGDB(int) {
// Don't come back here
signal(SIGTRAP, SIG_IGN);
const int newPort = serverGlobalParams.port + 2000;
char pidToDebug[16];
int pidRet = snprintf(pidToDebug, sizeof(pidToDebug), "%d", getpid());
invariant(pidRet >= 0 && size_t(pidRet) < sizeof(pidToDebug));
char hostPort[32];
int hostRet = snprintf(hostPort, sizeof(hostPort), "localhost:%d", newPort);
invariant(hostRet >= 0 && size_t(hostRet) < sizeof(hostPort));
char msg[128];
int msgRet = snprintf(msg, sizeof(msg),
"\n\n\t**** Launching gdbserver on %s ****\n\n", hostPort);
invariant(msgRet >= 0 && size_t(msgRet) < sizeof(msg));
invariant(write(STDERR_FILENO, msg, msgRet) == msgRet);
if (fork() == 0) {
//child
execlp("gdbserver", "gdbserver", "--attach", hostPort, pidToDebug, NULL);
perror(NULL);
_exit(1);
}
else {
//parent
raise(SIGSTOP); // pause all threads until gdb connects and continues
raise(SIGTRAP); // break inside gdbserver
}
}
void setupSIGTRAPforGDB() {
verify( signal(SIGTRAP , launchGDB ) != SIG_ERR );
}
#else
void setupSIGTRAPforGDB() {
}
#endif
}
|
