aboutsummaryrefslogtreecommitdiffstats
path: root/src/dmon.c
blob: 69bc77af39ce217c23acfab093b53e7d286075e7 (plain) (blame)
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
/*
 * Calcurse - text-based organizer
 *
 * Copyright (c) 2004-2017 calcurse Development Team <misc@calcurse.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the
 *        following disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the
 *        following disclaimer in the documentation and/or other
 *        materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Send your feedback or comments to : misc@calcurse.org
 * Calcurse home page : http://calcurse.org
 *
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <paths.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>
#include <signal.h>

#include "calcurse.h"

#define DMON_SLEEP_TIME  60

#define DMON_LOG(...) do {                                      \
  if (dmon.log)                                                 \
    io_fprintln (path_dmon_log, __VA_ARGS__);                   \
} while (0)

#define DMON_ABRT(...) do {                                     \
  DMON_LOG (__VA_ARGS__);                                       \
  if (kill (getpid (), SIGINT) < 0)                             \
    {                                                           \
      DMON_LOG (_("Could not stop daemon properly: %s\n"),      \
                strerror (errno));                              \
      exit (EXIT_FAILURE);                                      \
    }                                                           \
} while (0)

static unsigned data_loaded;

static void dmon_sigs_hdlr(int sig)
{
	if (sig == SIGUSR1) {
		want_reload = 1;
		return;
	}

	if (data_loaded)
		free_user_data();

	DMON_LOG(_("terminated at %s with signal %d\n"), nowstr(), sig);

	if (unlink(path_dpid) != 0) {
		DMON_LOG(_("Could not remove daemon lock file: %s\n"),
			 strerror(errno));
		exit(EXIT_FAILURE);
	}

	exit(EXIT_SUCCESS);
}

static unsigned daemonize(int status)
{
	int fd;

	/*
	 * Operate in the background: Daemonizing.
	 *
	 * First need to fork in order to become a child of the init process,
	 * once the father exits.
	 */
	switch (fork()) {
	case -1:		/* fork error */
		EXIT(_("Could not fork: %s\n"), strerror(errno));
		break;
	case 0:		/* child */
		break;
	default:		/* parent */
		exit(status);
	}

	/*
	 * Process independency.
	 *
	 * Obtain a new process group and session in order to get detached from the
	 * controlling terminal.
	 */
	if (setsid() == -1) {
		DMON_LOG(_("Could not detach from the controlling terminal: %s\n"),
			 strerror(errno));
		return 0;
	}

	/*
	 * Change working directory to root directory,
	 * to prevent filesystem unmounts.
	 */
	if (chdir("/") == -1) {
		DMON_LOG(_("Could not change working directory: %s\n"),
			 strerror(errno));
		return 0;
	}

	/* Redirect standard file descriptors to /dev/null. */
	if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
		dup2(fd, STDIN_FILENO);
		dup2(fd, STDOUT_FILENO);
		dup2(fd, STDERR_FILENO);
		if (fd > 2)
			close(fd);
	}

	/* Write access for the owner only. */
	umask(0022);

	if (!sigs_set_hdlr(SIGINT, dmon_sigs_hdlr)
	    || !sigs_set_hdlr(SIGTERM, dmon_sigs_hdlr)
	    || !sigs_set_hdlr(SIGALRM, dmon_sigs_hdlr)
	    || !sigs_set_hdlr(SIGQUIT, dmon_sigs_hdlr)
	    || !sigs_set_hdlr(SIGUSR1, dmon_sigs_hdlr)
	    || !sigs_set_hdlr(SIGCHLD, SIG_IGN))
		return 0;

	return 1;
}

void dmon_start(int parent_exit_status)
{
	if (!daemonize(parent_exit_status))
		DMON_ABRT(_("Cannot daemonize, aborting\n"));

	if (!io_dump_pid(path_dpid))
		DMON_ABRT(_("Could not set lock file\n"));

	if (!io_file_exists(path_conf))
		DMON_ABRT(_("Could not access \"%s\": %s\n"), path_conf,
			  strerror(errno));
	config_load();

	if (!io_file_exists(path_apts))
		DMON_ABRT(_("Could not access \"%s\": %s\n"), path_apts,
			  strerror(errno));
	apoint_llist_init();
	recur_apoint_llist_init();
	event_llist_init();
	recur_event_llist_init();
	todo_init_list();
	io_load_app(NULL);
	data_loaded = 1;

	DMON_LOG(_("started at %s\n"), nowstr());
	for (;;) {
		int left;

		if (want_reload) {
			want_reload = 0;
			io_reload_data();
			notify_check_next_app(1);
		}

		if (!notify_get_next_bkgd())
			DMON_ABRT(_("error loading next appointment\n"));

		left = notify_time_left();
		if (left > 0 && left < nbar.cntdwn
		    && notify_needs_reminder()) {
			DMON_LOG(_("launching notification at %s for: \"%s\"\n"),
				 nowstr(), notify_app_txt());
			if (!notify_launch_cmd())
				DMON_LOG(_("error while sending notification\n"));
		}

		DMON_LOG(ngettext("sleeping at %s for %d second\n",
				  "sleeping at %s for %d seconds\n",
				  DMON_SLEEP_TIME), nowstr(),
			 DMON_SLEEP_TIME);
		psleep(DMON_SLEEP_TIME);
		DMON_LOG(_("awakened at %s\n"), nowstr());
	}
}

/*
 * Check if calcurse is running in background, and if yes, send a SIGINT
 * signal to stop it.
 */
void dmon_stop(void)
{
	int dpid;

	dpid = io_get_pid(path_dpid);
	if (!dpid)
		return;

	if (kill((pid_t) dpid, SIGINT) < 0 && errno != ESRCH)
		EXIT(_("Could not stop calcurse daemon: %s\n"),
		     strerror(errno));
}