1 |
torben |
26 |
#include <iostream> |
2 |
|
|
|
3 |
|
|
#include <signal.h> |
4 |
|
|
#include <fcntl.h> |
5 |
torben |
114 |
#include <stdlib.h> |
6 |
|
|
#include <cstring> |
7 |
torben |
26 |
|
8 |
|
|
#include "daemon.h" |
9 |
|
|
#include "common.h" |
10 |
|
|
|
11 |
|
|
|
12 |
|
|
|
13 |
|
|
using namespace std; |
14 |
|
|
|
15 |
|
|
|
16 |
|
|
void signal_handler(int sig) |
17 |
|
|
{ |
18 |
|
|
switch(sig) { |
19 |
|
|
case SIGHUP: |
20 |
|
|
Common::instance()->logMessage("hangup signal catched"); |
21 |
|
|
break; |
22 |
|
|
|
23 |
|
|
case SIGTERM: |
24 |
|
|
Common::instance()->logMessage("terminate signal catched...exiting"); |
25 |
|
|
Common::instance()->mainContinue = false; |
26 |
|
|
break; |
27 |
|
|
} |
28 |
|
|
} |
29 |
|
|
|
30 |
|
|
void daemonCleanup() |
31 |
|
|
{ |
32 |
|
|
unlink( Common::instance()->pidfile.c_str() ); |
33 |
|
|
} |
34 |
|
|
|
35 |
|
|
void daemonize() |
36 |
|
|
{ |
37 |
|
|
int i, lfp; |
38 |
|
|
char str[10]; |
39 |
|
|
Common* cmn = Common::instance(); |
40 |
|
|
|
41 |
|
|
if (getuid() != 0) |
42 |
|
|
{ |
43 |
|
|
cout << "Please start this daemon as root\n" << endl; |
44 |
|
|
daemon_shutdown(0); |
45 |
|
|
} |
46 |
|
|
|
47 |
|
|
|
48 |
|
|
if (getppid() == 1) /* already a daemon */ |
49 |
|
|
return; |
50 |
|
|
|
51 |
|
|
i=fork(); |
52 |
|
|
|
53 |
|
|
if (i<0) /* fork error */ |
54 |
|
|
daemon_shutdown(FORK_ERROR); |
55 |
|
|
if (i>0) /* parent exits */ |
56 |
|
|
daemon_shutdown(0); |
57 |
|
|
/* child daemon continues */ |
58 |
|
|
|
59 |
|
|
setsid(); /* obtain a new process group */ |
60 |
|
|
|
61 |
|
|
for (i=getdtablesize(); i>=0; --i) |
62 |
|
|
close(i); /*close all descriptors*/ |
63 |
|
|
|
64 |
|
|
i=open("/dev/null", O_RDWR); /* handle std. io */ |
65 |
|
|
dup(i); |
66 |
|
|
dup(i); |
67 |
|
|
|
68 |
|
|
umask(027); /* set newly created file permissions */ |
69 |
|
|
|
70 |
|
|
chdir("/tmp"); /* change running directory*/ |
71 |
|
|
|
72 |
|
|
/*attempt to create lockfile and put a file-lock on it*/ |
73 |
|
|
lfp=open(cmn->pidfile.c_str(), O_RDWR|O_CREAT, 0640); |
74 |
|
|
if (lfp<0) /* can not open */ |
75 |
|
|
daemon_shutdown(CANT_OPEN_LOCK); |
76 |
|
|
if (lockf(lfp,F_TLOCK,0) < 0) /* can not lock */ |
77 |
|
|
daemon_shutdown(ALREADY_LOCKED); |
78 |
|
|
|
79 |
|
|
/* first instance continues */ |
80 |
|
|
sprintf(str, "%d\n", getpid() ); /* record pid to lockfile */ |
81 |
|
|
write(lfp, str, strlen(str) ); |
82 |
torben |
86 |
//signal(SIGCHLD, SIG_IGN); /* ignore child */ |
83 |
torben |
26 |
signal(SIGTSTP, SIG_IGN); /* ignore tty signals */ |
84 |
|
|
signal(SIGTTOU, SIG_IGN); |
85 |
|
|
signal(SIGTTIN, SIG_IGN); |
86 |
|
|
signal(SIGHUP, signal_handler); /* catch hangup signal */ |
87 |
|
|
signal(SIGTERM, signal_handler); /* catch kill signal */ |
88 |
|
|
|
89 |
|
|
/*this program is now a daemon*/ |
90 |
|
|
setegid( cmn->gid ); |
91 |
|
|
seteuid( cmn->uid ); |
92 |
|
|
} |