summaryrefslogtreecommitdiff
path: root/runit/runsvdir.c
blob: 9238eec82e4ed326e2edeb24439aadc769ebdc53 (plain)
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
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
/* Busyboxed by Denis Vlasenko <vda.linux@googlemail.com> */
/* TODO: depends on runit_lib.c - review and reduce/eliminate */

#include <sys/poll.h>
#include <sys/file.h>
#include "busybox.h"
#include "runit_lib.h"

#define MAXSERVICES 1000

static char *svdir;
static unsigned long dev;
static unsigned long ino;
static struct service {
	unsigned long dev;
	unsigned long ino;
	int pid;
	int isgone;
} *sv;
static int svnum;
static int check = 1;
static char *rplog;
static int rploglen;
static int logpipe[2];
static iopause_fd io[1];
static struct taia stamplog;
static int exitsoon;
static int pgrp;

#define usage() bb_show_usage()
static void fatal2_cannot(char *m1, char *m2)
{
	bb_perror_msg_and_die("%s: fatal: cannot %s%s", svdir, m1, m2);
	/* was exiting 100 */
}
static void warn3x(char *m1, char *m2, char *m3)
{
	bb_error_msg("%s: warning: %s%s%s", svdir, m1, m2, m3);
} 
static void warn2_cannot(char *m1, char *m2)
{
	warn3x("cannot ", m1, m2);
}
static void warnx(char *m1)
{
	warn3x(m1, "", "");
} 

static void s_term(int sig_no)
{
	exitsoon = 1;
}
static void s_hangup(int sig_no)
{
	exitsoon = 2;
}

static void runsv(int no, char *name)
{
	int pid = fork();

	if (pid == -1) {
		warn2_cannot("fork for ", name);
		return;
	}
	if (pid == 0) {
		/* child */
		char *prog[3];

		prog[0] = "runsv";
		prog[1] = name;
		prog[2] = 0;
		sig_uncatch(sig_hangup);
		sig_uncatch(sig_term);
		if (pgrp) setsid();
		execvp(prog[0], prog);
		//pathexec_run(*prog, prog, (char* const*)environ);
		fatal2_cannot("start runsv ", name);
	}
	sv[no].pid = pid;
}

static void runsvdir(void)
{
	DIR *dir;
	direntry *d;
	int i;
	struct stat s;

	dir = opendir(".");
	if (!dir) {
		warn2_cannot("open directory ", svdir);
		return;
	}
	for (i = 0; i < svnum; i++)
		sv[i].isgone = 1;
	errno = 0;
	while ((d = readdir(dir))) {
		if (d->d_name[0] == '.') continue;
		if (stat(d->d_name, &s) == -1) {
			warn2_cannot("stat ", d->d_name);
			errno = 0;
			continue;
		}
		if (!S_ISDIR(s.st_mode)) continue;
		for (i = 0; i < svnum; i++) {
			if ((sv[i].ino == s.st_ino) && (sv[i].dev == s.st_dev)) {
				sv[i].isgone = 0;
				if (!sv[i].pid)
					runsv(i, d->d_name);
				break;
			}
		}
		if (i == svnum) {
			/* new service */
			struct service *svnew = realloc(sv, (i+1) * sizeof(*sv));
			if (!svnew) {
				warn3x("cannot start runsv ", d->d_name,
						" too many services");
				continue;
			}
			sv = svnew;
			svnum++;
			memset(&sv[i], 0, sizeof(sv[i]));
			sv[i].ino = s.st_ino;
			sv[i].dev = s.st_dev;
			//sv[i].pid = 0;
			//sv[i].isgone = 0;
			runsv(i, d->d_name);
			check = 1;
		}
	}
	if (errno) {
		warn2_cannot("read directory ", svdir);
		closedir(dir);
		check = 1;
		return;
	}
	closedir(dir);

	/* SIGTERM removed runsv's */
	for (i = 0; i < svnum; i++) {
		if (!sv[i].isgone)
			continue;
		if (sv[i].pid)
			kill(sv[i].pid, SIGTERM);
		sv[i] = sv[--svnum];
		check = 1;
	}
}

static int setup_log(void)
{
	rploglen = strlen(rplog);
	if (rploglen < 7) {
		warnx("log must have at least seven characters");
		return 0;
	}
	if (pipe(logpipe) == -1) {
		warnx("cannot create pipe for log");
		return -1;
	}
	coe(logpipe[1]);
	coe(logpipe[0]);
	ndelay_on(logpipe[0]);
	ndelay_on(logpipe[1]);
	if (fd_copy(2, logpipe[1]) == -1) {
		warnx("cannot set filedescriptor for log");
		return -1;
	}
	io[0].fd = logpipe[0];
	io[0].events = IOPAUSE_READ;
	taia_now(&stamplog);
	return 1;
}

int runsvdir_main(int argc, char **argv)
{
	struct stat s;
	time_t mtime = 0;
	int wstat;
	int curdir;
	int pid;
	struct taia deadline;
	struct taia now;
	struct taia stampcheck;
	char ch;
	int i;

	argv++;
	if (!argv || !*argv) usage();
	if (**argv == '-') {
		switch (*(*argv + 1)) {
		case 'P': pgrp = 1;
		case '-': ++argv;
		}
		if (!argv || !*argv) usage();
	}

	sig_catch(sig_term, s_term);
	sig_catch(sig_hangup, s_hangup);
	svdir = *argv++;
	if (argv && *argv) {
		rplog = *argv;
		if (setup_log() != 1) {
			rplog = 0;
			warnx("log service disabled");
		}
	}
	curdir = open_read(".");
	if (curdir == -1) 
		fatal2_cannot("open current directory", "");
	coe(curdir);

	taia_now(&stampcheck);

	for (;;) {
		/* collect children */
		for (;;) {
			pid = wait_nohang(&wstat);
			if (pid <= 0) break;
			for (i = 0; i < svnum; i++) {
				if (pid == sv[i].pid) {
					/* runsv has gone */
					sv[i].pid = 0;
					check = 1;
					break;
				}
			}
		}

		taia_now(&now);
		if (now.sec.x < (stampcheck.sec.x - 3)) {
			/* time warp */
			warnx("time warp: resetting time stamp");
			taia_now(&stampcheck);
			taia_now(&now);
			if (rplog) taia_now(&stamplog);
		}
		if (taia_less(&now, &stampcheck) == 0) {
			/* wait at least a second */
			taia_uint(&deadline, 1);
			taia_add(&stampcheck, &now, &deadline);
			
			if (stat(svdir, &s) != -1) {
				if (check || s.st_mtime != mtime
				 || s.st_ino != ino || s.st_dev != dev
				) {
					/* svdir modified */
					if (chdir(svdir) != -1) {
						mtime = s.st_mtime;
						dev = s.st_dev;
						ino = s.st_ino;
						check = 0;
						if (now.sec.x <= (4611686018427387914ULL + (uint64_t)mtime))
							sleep(1);
						runsvdir();
						while (fchdir(curdir) == -1) {
							warn2_cannot("change directory, pausing", "");
							sleep(5);
						}
					} else
						warn2_cannot("change directory to ", svdir);
				}
			} else
				warn2_cannot("stat ", svdir);
		}

		if (rplog) {
			if (taia_less(&now, &stamplog) == 0) {
				write(logpipe[1], ".", 1);
				taia_uint(&deadline, 900);
				taia_add(&stamplog, &now, &deadline);
			}
		}
		taia_uint(&deadline, check ? 1 : 5);
		taia_add(&deadline, &now, &deadline);

		sig_block(sig_child);
		if (rplog)
			iopause(io, 1, &deadline, &now);
		else
			iopause(0, 0, &deadline, &now);
		sig_unblock(sig_child);

		if (rplog && (io[0].revents | IOPAUSE_READ))
			while (read(logpipe[0], &ch, 1) > 0)
				if (ch) {
					for (i = 6; i < rploglen; i++)
						rplog[i-1] = rplog[i];
					rplog[rploglen-1] = ch;
				}

		switch (exitsoon) {
		case 1:
			_exit(0);
		case 2:
			for (i = 0; i < svnum; i++)
				if (sv[i].pid)
					kill(sv[i].pid, SIGTERM);
			_exit(111);
		}
	}
	/* not reached */
	return 0;
}