projects/smsdaemon/daemon.cpp

#include <iostream>
#include <sstream>
#include <signal.h>
#include <fcntl.h>
#include <stdlib.h>
#include <cstring>

#include <sys/types.h>
#include <pwd.h>
#include <grp.h>


#include "ConfigFile.h"
#include "daemon.h"
#include "common.h"


using namespace std;


void signal_handler(int sig)
{
        switch (sig)
        {
        case SIGHUP:
                Common::instance()->logMessage("hangup signal catched");
                break;

        case SIGTERM:
                Common::instance()->logMessage("terminate signal catched...exiting");
                Common::instance()->mainContinue = false;
                break;
        default:
                std::stringstream ss;
                ss << "Received unknown signal: " << sig;
                Common::instance()->logMessage(ss.str());
                break;
        }
}

void lookup_uid_values()
{
        Common* cmn = Common::instance();

        std::string userstr = cmn->GetConfigfile()->GetValue("smsdaemon","user");
        std::string groupstr = cmn->GetConfigfile()->GetValue("smsdaemon","group");

        passwd* pass = getpwnam(userstr.c_str());
        if (pass != 0)
        {
                cmn->uid = pass->pw_uid;
        }
        else
        {
                cmn->logMessage( string("could not lookup userid: ") + userstr );
                exit(1);
        }


        group* grp = getgrnam(groupstr.c_str() );
        if (grp != 0)
        {
                cmn->gid = grp->gr_gid;
        }
        else
        {
                cmn->logMessage( string("could not lookup groupid: ") + groupstr );
                exit(1);
        }
}


void daemonCleanup()
{
        unlink( Common::instance()->pidfile.c_str() );
}

void daemonize()
{
        int i, lfp;
        char str[10];
        Common* cmn = Common::instance();

        if (getuid() != 0)
        {
                cout << "Please start this daemon as root\n" << endl;
                daemon_shutdown(0);
        }


        if (getppid() == 1) /* already a daemon */
                return;

        i=fork();

        if (i<0) /* fork error */
                daemon_shutdown(FORK_ERROR);
        if (i>0) /* parent exits */
                daemon_shutdown(0);
        /* child daemon continues */

        setsid(); /* obtain a new process group */

        for (i=getdtablesize(); i>=0; --i)
                close(i); /*close all descriptors*/

        i=open("/dev/null", O_RDWR); /* handle std. io */
        dup(i);
        dup(i);

        umask(027); /* set newly created file permissions */

        chdir("/tmp"); /* change running directory*/

        /*attempt to create lockfile and put a file-lock on it*/
        lfp=open(cmn->pidfile.c_str(), O_RDWR|O_CREAT, 0640);
        if (lfp<0) /* can not open */
                daemon_shutdown(CANT_OPEN_LOCK);
        if (lockf(lfp,F_TLOCK,0) < 0) /* can not lock */
                daemon_shutdown(ALREADY_LOCKED);

        /* first instance continues */
        sprintf(str, "%d\n", getpid() ); /* record pid to lockfile */
        write(lfp, str, strlen(str) );
        //signal(SIGCHLD, SIG_IGN); /* ignore child */
        signal(SIGTSTP, SIG_IGN); /* ignore tty signals */
        signal(SIGTTOU, SIG_IGN);
        signal(SIGTTIN, SIG_IGN);
        signal(SIGHUP, signal_handler); /* catch hangup signal */
        signal(SIGTERM, signal_handler); /* catch kill signal */
        signal(SIGINT, signal_handler); /* keyboard interrupt */
        signal(SIGQUIT, signal_handler); /* QUIT */

        /*this program is now a daemon*/
        setegid( cmn->gid );
        seteuid( cmn->uid );
}
1	torben	26	#include <iostream>
2	torben	153	#include <sstream>
3	torben	26	#include <signal.h>
4			#include <fcntl.h>
5	torben	114	#include <stdlib.h>
6			#include <cstring>
7	torben	26
8	torben	146	#include <sys/types.h>
9			#include <pwd.h>
10			#include <grp.h>
11
12
13	torben	152	#include "ConfigFile.h"
14	torben	26	#include "daemon.h"
15			#include "common.h"
16
17
18
19			using namespace std;
20
21	torben	146
22	torben	26	void signal_handler(int sig)
23			{
24	torben	146	switch (sig)
25			{
26			case SIGHUP:
27			Common::instance()->logMessage("hangup signal catched");
28			break;
29	torben	26
30	torben	146	case SIGTERM:
31			Common::instance()->logMessage("terminate signal catched...exiting");
32			Common::instance()->mainContinue = false;
33			break;
34	torben	153	default:
35			std::stringstream ss;
36			ss << "Received unknown signal: " << sig;
37			Common::instance()->logMessage(ss.str());
38			break;
39	torben	26	}
40			}
41
42	torben	146	void lookup_uid_values()
43			{
44			Common* cmn = Common::instance();
45
46	torben	152	std::string userstr = cmn->GetConfigfile()->GetValue("smsdaemon","user");
47			std::string groupstr = cmn->GetConfigfile()->GetValue("smsdaemon","group");
48
49			passwd* pass = getpwnam(userstr.c_str());
50	torben	146	if (pass != 0)
51			{
52			cmn->uid = pass->pw_uid;
53			}
54			else
55			{
56	torben	152	cmn->logMessage( string("could not lookup userid: ") + userstr );
57	torben	146	exit(1);
58			}
59
60	torben	155
61	torben	152	group* grp = getgrnam(groupstr.c_str() );
62	torben	146	if (grp != 0)
63			{
64			cmn->gid = grp->gr_gid;
65			}
66			else
67			{
68	torben	152	cmn->logMessage( string("could not lookup groupid: ") + groupstr );
69	torben	146	exit(1);
70			}
71			}
72
73
74	torben	26	void daemonCleanup()
75			{
76			unlink( Common::instance()->pidfile.c_str() );
77			}
78
79			void daemonize()
80	torben	146	{
81	torben	26	int i, lfp;
82			char str[10];
83			Common* cmn = Common::instance();
84
85			if (getuid() != 0)
86			{
87			cout << "Please start this daemon as root\n" << endl;
88			daemon_shutdown(0);
89			}
90
91	torben	146
92	torben	26	if (getppid() == 1) /* already a daemon */
93			return;
94	torben	146
95	torben	26	i=fork();
96	torben	146
97	torben	26	if (i<0) /* fork error */
98			daemon_shutdown(FORK_ERROR);
99			if (i>0) /* parent exits */
100			daemon_shutdown(0);
101			/* child daemon continues */
102	torben	146
103	torben	26	setsid(); /* obtain a new process group */
104	torben	146
105	torben	26	for (i=getdtablesize(); i>=0; --i)
106			close(i); /close all descriptors/
107	torben	146
108	torben	26	i=open("/dev/null", O_RDWR); /* handle std. io */
109			dup(i);
110	torben	146	dup(i);
111
112	torben	26	umask(027); /* set newly created file permissions */
113	torben	146
114	torben	26	chdir("/tmp"); /* change running directory*/
115	torben	146
116	torben	26	/attempt to create lockfile and put a file-lock on it/
117			lfp=open(cmn->pidfile.c_str(), O_RDWR\|O_CREAT, 0640);
118			if (lfp<0) /* can not open */
119			daemon_shutdown(CANT_OPEN_LOCK);
120			if (lockf(lfp,F_TLOCK,0) < 0) /* can not lock */
121			daemon_shutdown(ALREADY_LOCKED);
122	torben	146
123	torben	26	/* first instance continues */
124			sprintf(str, "%d\n", getpid() ); /* record pid to lockfile */
125			write(lfp, str, strlen(str) );
126	torben	86	//signal(SIGCHLD, SIG_IGN); /* ignore child */
127	torben	26	signal(SIGTSTP, SIG_IGN); /* ignore tty signals */
128			signal(SIGTTOU, SIG_IGN);
129			signal(SIGTTIN, SIG_IGN);
130			signal(SIGHUP, signal_handler); /* catch hangup signal */
131	torben	146	signal(SIGTERM, signal_handler); /* catch kill signal */
132	torben	155	signal(SIGINT, signal_handler); /* keyboard interrupt */
133			signal(SIGQUIT, signal_handler); /* QUIT */
134	torben	26
135			/this program is now a daemon/
136			setegid( cmn->gid );
137			seteuid( cmn->uid );
138			}