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-rw-r--r--runit/runsv.c613
1 files changed, 613 insertions, 0 deletions
diff --git a/runit/runsv.c b/runit/runsv.c
new file mode 100644
index 000000000..e1b5459fb
--- /dev/null
+++ b/runit/runsv.c
@@ -0,0 +1,613 @@
1/* Busyboxed by Denis Vlasenko <vda.linux@googlemail.com> */
2/* TODO: depends on runit_lib.c - review and reduce/eliminate */
3
4#include <sys/poll.h>
5#include <sys/file.h>
6#include "busybox.h"
7#include "runit_lib.h"
8
9static int selfpipe[2];
10
11/* state */
12#define S_DOWN 0
13#define S_RUN 1
14#define S_FINISH 2
15/* ctrl */
16#define C_NOOP 0
17#define C_TERM 1
18#define C_PAUSE 2
19/* want */
20#define W_UP 0
21#define W_DOWN 1
22#define W_EXIT 2
23
24struct svdir {
25 int pid;
26 int state;
27 int ctrl;
28 int want;
29 struct taia start;
30 int fdlock;
31 int fdcontrol;
32 int fdcontrolwrite;
33 int islog;
34};
35static struct svdir svd[2];
36
37static int sigterm = 0;
38static int haslog = 0;
39static int pidchanged = 1;
40static int logpipe[2];
41static char *dir;
42
43#define usage() bb_show_usage()
44
45static void fatal2_cannot(char *m1, char *m2)
46{
47 bb_perror_msg_and_die("%s: fatal: cannot %s%s", dir, m1, m2);
48 /* was exiting 111 */
49}
50static void fatal_cannot(char *m)
51{
52 fatal2_cannot(m, "");
53 /* was exiting 111 */
54}
55static void fatal2x_cannot(char *m1, char *m2)
56{
57 bb_error_msg_and_die("%s: fatal: cannot %s%s", dir, m1, m2);
58 /* was exiting 111 */
59}
60static void warn_cannot(char *m)
61{
62 bb_perror_msg("%s: warning: cannot %s", dir, m);
63}
64static void warnx_cannot(char *m)
65{
66 bb_error_msg("%s: warning: cannot %s", dir, m);
67}
68
69static void stopservice(struct svdir *);
70
71static void s_child(int sig_no)
72{
73 write(selfpipe[1], "", 1);
74}
75
76static void s_term(int sig_no)
77{
78 sigterm = 1;
79 write(selfpipe[1], "", 1); /* XXX */
80}
81
82static char *add_str(char *p, const char *to_add)
83{
84 while ((*p = *to_add) != '\0') {
85 p++;
86 to_add++;
87 }
88 return p;
89}
90
91static int open_trunc_or_warn(const char *name)
92{
93 int fd = open_trunc(name);
94 if (fd < 0)
95 bb_perror_msg("%s: warning: cannot open %s",
96 dir, name);
97 return fd;
98}
99
100static int rename_or_warn(const char *old, const char *new)
101{
102 if (rename(old, new) == -1) {
103 bb_perror_msg("%s: warning: cannot rename %s to %s",
104 dir, old, new);
105 return -1;
106 }
107 return 0;
108}
109
110static void update_status(struct svdir *s)
111{
112 unsigned long l;
113 int fd;
114 char status[20];
115
116 /* pid */
117 if (pidchanged) {
118 fd = open_trunc_or_warn("supervise/pid.new");
119 if (fd < 0)
120 return;
121 if (s->pid) {
122 char spid[sizeof(s->pid)*3 + 2];
123 int size = sprintf(spid, "%d\n", s->pid);
124 write(fd, spid, size);
125 }
126 close(fd);
127 if (s->islog) {
128 if (rename_or_warn("supervise/pid.new", "log/supervise/pid"))
129 return;
130 } else if (rename_or_warn("supervise/pid.new", "supervise/pid")) {
131 return;
132 }
133 pidchanged = 0;
134 }
135
136 /* stat */
137 fd = open_trunc_or_warn("supervise/stat.new");
138 if (fd < -1)
139 return;
140
141 {
142 char stat_buf[sizeof("finish, paused, got TERM, want down\n")];
143 char *p = stat_buf;
144 switch (s->state) {
145 case S_DOWN:
146 p = add_str(p, "down");
147 break;
148 case S_RUN:
149 p = add_str(p, "run");
150 break;
151 case S_FINISH:
152 p = add_str(p, "finish");
153 break;
154 }
155 if (s->ctrl & C_PAUSE) p = add_str(p, ", paused");
156 if (s->ctrl & C_TERM) p = add_str(p, ", got TERM");
157 if (s->state != S_DOWN)
158 switch(s->want) {
159 case W_DOWN:
160 p = add_str(p, ", want down");
161 break;
162 case W_EXIT:
163 p = add_str(p, ", want exit");
164 break;
165 }
166 *p++ = '\n';
167 write(fd, stat_buf, p - stat_buf);
168 close(fd);
169 }
170
171 if (s->islog) {
172 rename_or_warn("supervise/stat.new", "log/supervise/stat");
173 } else {
174 rename_or_warn("supervise/stat.new", "log/supervise/stat"+4);
175 }
176
177 /* supervise compatibility */
178 taia_pack(status, &s->start);
179 l = (unsigned long)s->pid;
180 status[12] = l; l >>=8;
181 status[13] = l; l >>=8;
182 status[14] = l; l >>=8;
183 status[15] = l;
184 if (s->ctrl & C_PAUSE)
185 status[16] = 1;
186 else
187 status[16] = 0;
188 if (s->want == W_UP)
189 status[17] = 'u';
190 else
191 status[17] = 'd';
192 if (s->ctrl & C_TERM)
193 status[18] = 1;
194 else
195 status[18] = 0;
196 status[19] = s->state;
197 fd = open_trunc_or_warn("supervise/status.new");
198 if (fd < 0)
199 return;
200 l = write(fd, status, sizeof status);
201 if (l < 0) {
202 warn_cannot("write supervise/status.new");
203 close(fd);
204 unlink("supervise/status.new");
205 return;
206 }
207 close(fd);
208 if (l < sizeof status) {
209 warnx_cannot("write supervise/status.new: partial write");
210 return;
211 }
212 if (s->islog) {
213 rename_or_warn("supervise/status.new", "log/supervise/status");
214 } else {
215 rename_or_warn("supervise/status.new", "log/supervise/status"+4);
216 }
217}
218
219static unsigned custom(struct svdir *s, char c)
220{
221 int pid;
222 int w;
223 char a[10];
224 struct stat st;
225 char *prog[2];
226
227 if (s->islog) return 0;
228 memcpy(a, "control/?", 10);
229 a[8] = c;
230 if (stat(a, &st) == 0) {
231 if (st.st_mode & S_IXUSR) {
232 pid = fork();
233 if (pid == -1) {
234 warn_cannot("fork for control/?");
235 return 0;
236 }
237 if (!pid) {
238 if (haslog && fd_copy(1, logpipe[1]) == -1)
239 warn_cannot("setup stdout for control/?");
240 prog[0] = a;
241 prog[1] = 0;
242 execve(a, prog, environ);
243 fatal_cannot("run control/?");
244 }
245 while (wait_pid(&w, pid) == -1) {
246 if (errno == EINTR) continue;
247 warn_cannot("wait for child control/?");
248 return 0;
249 }
250 return !wait_exitcode(w);
251 }
252 }
253 else {
254 if (errno == ENOENT) return 0;
255 warn_cannot("stat control/?");
256 }
257 return 0;
258}
259
260static void stopservice(struct svdir *s)
261{
262 if (s->pid && ! custom(s, 't')) {
263 kill(s->pid, SIGTERM);
264 s->ctrl |=C_TERM;
265 update_status(s);
266 }
267 if (s->want == W_DOWN) {
268 kill(s->pid, SIGCONT);
269 custom(s, 'd'); return;
270 }
271 if (s->want == W_EXIT) {
272 kill(s->pid, SIGCONT);
273 custom(s, 'x');
274 }
275}
276
277static void startservice(struct svdir *s)
278{
279 int p;
280 char *run[2];
281
282 if (s->state == S_FINISH)
283 run[0] = "./finish";
284 else {
285 run[0] = "./run";
286 custom(s, 'u');
287 }
288 run[1] = 0;
289
290 if (s->pid != 0) stopservice(s); /* should never happen */
291 while ((p = fork()) == -1) {
292 warn_cannot("fork, sleeping");
293 sleep(5);
294 }
295 if (p == 0) {
296 /* child */
297 if (haslog) {
298 if (s->islog) {
299 if (fd_copy(0, logpipe[0]) == -1)
300 fatal_cannot("setup filedescriptor for ./log/run");
301 close(logpipe[1]);
302 if (chdir("./log") == -1)
303 fatal_cannot("change directory to ./log");
304 } else {
305 if (fd_copy(1, logpipe[1]) == -1)
306 fatal_cannot("setup filedescriptor for ./run");
307 close(logpipe[0]);
308 }
309 }
310 sig_uncatch(sig_child);
311 sig_unblock(sig_child);
312 sig_uncatch(sig_term);
313 sig_unblock(sig_term);
314 execve(*run, run, environ);
315 if (s->islog)
316 fatal2_cannot("start log/", *run);
317 else
318 fatal2_cannot("start ", *run);
319 }
320 if (s->state != S_FINISH) {
321 taia_now(&s->start);
322 s->state = S_RUN;
323 }
324 s->pid = p;
325 pidchanged = 1;
326 s->ctrl = C_NOOP;
327 update_status(s);
328}
329
330static int ctrl(struct svdir *s, char c)
331{
332 switch(c) {
333 case 'd': /* down */
334 s->want = W_DOWN;
335 update_status(s);
336 if (s->pid && s->state != S_FINISH) stopservice(s);
337 break;
338 case 'u': /* up */
339 s->want = W_UP;
340 update_status(s);
341 if (s->pid == 0) startservice(s);
342 break;
343 case 'x': /* exit */
344 if (s->islog) break;
345 s->want = W_EXIT;
346 update_status(s);
347 if (s->pid && s->state != S_FINISH) stopservice(s);
348 break;
349 case 't': /* sig term */
350 if (s->pid && s->state != S_FINISH) stopservice(s);
351 break;
352 case 'k': /* sig kill */
353 if (s->pid && ! custom(s, c)) kill(s->pid, SIGKILL);
354 s->state = S_DOWN;
355 break;
356 case 'p': /* sig pause */
357 if (s->pid && ! custom(s, c)) kill(s->pid, SIGSTOP);
358 s->ctrl |=C_PAUSE;
359 update_status(s);
360 break;
361 case 'c': /* sig cont */
362 if (s->pid && ! custom(s, c)) kill(s->pid, SIGCONT);
363 if (s->ctrl & C_PAUSE) s->ctrl &=~C_PAUSE;
364 update_status(s);
365 break;
366 case 'o': /* once */
367 s->want = W_DOWN;
368 update_status(s);
369 if (!s->pid) startservice(s);
370 break;
371 case 'a': /* sig alarm */
372 if (s->pid && ! custom(s, c)) kill(s->pid, SIGALRM);
373 break;
374 case 'h': /* sig hup */
375 if (s->pid && ! custom(s, c)) kill(s->pid, SIGHUP);
376 break;
377 case 'i': /* sig int */
378 if (s->pid && ! custom(s, c)) kill(s->pid, SIGINT);
379 break;
380 case 'q': /* sig quit */
381 if (s->pid && ! custom(s, c)) kill(s->pid, SIGQUIT);
382 break;
383 case '1': /* sig usr1 */
384 if (s->pid && ! custom(s, c)) kill(s->pid, SIGUSR1);
385 break;
386 case '2': /* sig usr2 */
387 if (s->pid && ! custom(s, c)) kill(s->pid, SIGUSR2);
388 break;
389 }
390 return 1;
391}
392
393int runsv_main(int argc, char **argv)
394{
395 struct stat s;
396 int fd;
397 int r;
398 char buf[256];
399
400 if (!argv[1] || argv[2]) usage();
401 dir = argv[1];
402
403 if (pipe(selfpipe) == -1) fatal_cannot("create selfpipe");
404 coe(selfpipe[0]);
405 coe(selfpipe[1]);
406 ndelay_on(selfpipe[0]);
407 ndelay_on(selfpipe[1]);
408
409 sig_block(sig_child);
410 sig_catch(sig_child, s_child);
411 sig_block(sig_term);
412 sig_catch(sig_term, s_term);
413
414 xchdir(dir);
415 svd[0].pid = 0;
416 svd[0].state = S_DOWN;
417 svd[0].ctrl = C_NOOP;
418 svd[0].want = W_UP;
419 svd[0].islog = 0;
420 svd[1].pid = 0;
421 taia_now(&svd[0].start);
422 if (stat("down", &s) != -1) svd[0].want = W_DOWN;
423
424 if (stat("log", &s) == -1) {
425 if (errno != ENOENT)
426 warn_cannot("stat ./log");
427 } else {
428 if (!S_ISDIR(s.st_mode))
429 warnx_cannot("stat log/down: log is not a directory");
430 else {
431 haslog = 1;
432 svd[1].state = S_DOWN;
433 svd[1].ctrl = C_NOOP;
434 svd[1].want = W_UP;
435 svd[1].islog = 1;
436 taia_now(&svd[1].start);
437 if (stat("log/down", &s) != -1)
438 svd[1].want = W_DOWN;
439 if (pipe(logpipe) == -1)
440 fatal_cannot("create log pipe");
441 coe(logpipe[0]);
442 coe(logpipe[1]);
443 }
444 }
445
446 if (mkdir("supervise", 0700) == -1) {
447 r = readlink("supervise", buf, 256);
448 if (r != -1) {
449 if (r == 256)
450 fatal2x_cannot("readlink ./supervise: ", "name too long");
451 buf[r] = 0;
452 mkdir(buf, 0700);
453 } else {
454 if ((errno != ENOENT) && (errno != EINVAL))
455 fatal_cannot("readlink ./supervise");
456 }
457 }
458 svd[0].fdlock = xopen3("log/supervise/lock"+4,
459 O_WRONLY|O_NDELAY|O_APPEND|O_CREAT, 0600);
460 if (lock_exnb(svd[0].fdlock) == -1)
461 fatal_cannot("lock supervise/lock");
462 coe(svd[0].fdlock);
463 if (haslog) {
464 if (mkdir("log/supervise", 0700) == -1) {
465 r = readlink("log/supervise", buf, 256);
466 if (r != -1) {
467 if (r == 256)
468 fatal2x_cannot("readlink ./log/supervise: ", "name too long");
469 buf[r] = 0;
470 fd = xopen(".", O_RDONLY|O_NDELAY);
471 xchdir("./log");
472 mkdir(buf, 0700);
473 if (fchdir(fd) == -1)
474 fatal_cannot("change back to service directory");
475 close(fd);
476 }
477 else {
478 if ((errno != ENOENT) && (errno != EINVAL))
479 fatal_cannot("readlink ./log/supervise");
480 }
481 }
482 svd[1].fdlock = xopen3("log/supervise/lock",
483 O_WRONLY|O_NDELAY|O_APPEND|O_CREAT, 0600);
484 if (lock_ex(svd[1].fdlock) == -1)
485 fatal_cannot("lock log/supervise/lock");
486 coe(svd[1].fdlock);
487 }
488
489 fifo_make("log/supervise/control"+4, 0600);
490 svd[0].fdcontrol = xopen("log/supervise/control"+4, O_RDONLY|O_NDELAY);
491 coe(svd[0].fdcontrol);
492 svd[0].fdcontrolwrite = xopen("log/supervise/control"+4, O_WRONLY|O_NDELAY);
493 coe(svd[0].fdcontrolwrite);
494 update_status(&svd[0]);
495 if (haslog) {
496 fifo_make("log/supervise/control", 0600);
497 svd[1].fdcontrol = xopen("log/supervise/control", O_RDONLY|O_NDELAY);
498 coe(svd[1].fdcontrol);
499 svd[1].fdcontrolwrite = xopen("log/supervise/control", O_WRONLY|O_NDELAY);
500 coe(svd[1].fdcontrolwrite);
501 update_status(&svd[1]);
502 }
503 fifo_make("log/supervise/ok"+4, 0600);
504 fd = xopen("log/supervise/ok"+4, O_RDONLY|O_NDELAY);
505 coe(fd);
506 if (haslog) {
507 fifo_make("log/supervise/ok", 0600);
508 fd = xopen("log/supervise/ok", O_RDONLY|O_NDELAY);
509 coe(fd);
510 }
511 for (;;) {
512 iopause_fd x[3];
513 struct taia deadline;
514 struct taia now;
515 char ch;
516
517 if (haslog)
518 if (!svd[1].pid && svd[1].want == W_UP)
519 startservice(&svd[1]);
520 if (!svd[0].pid)
521 if (svd[0].want == W_UP || svd[0].state == S_FINISH)
522 startservice(&svd[0]);
523
524 x[0].fd = selfpipe[0];
525 x[0].events = IOPAUSE_READ;
526 x[1].fd = svd[0].fdcontrol;
527 x[1].events = IOPAUSE_READ;
528 if (haslog) {
529 x[2].fd = svd[1].fdcontrol;
530 x[2].events = IOPAUSE_READ;
531 }
532 taia_now(&now);
533 taia_uint(&deadline, 3600);
534 taia_add(&deadline, &now, &deadline);
535
536 sig_unblock(sig_term);
537 sig_unblock(sig_child);
538 iopause(x, 2+haslog, &deadline, &now);
539 sig_block(sig_term);
540 sig_block(sig_child);
541
542 while (read(selfpipe[0], &ch, 1) == 1)
543 ;
544 for (;;) {
545 int child;
546 int wstat;
547
548 child = wait_nohang(&wstat);
549 if (!child) break;
550 if ((child == -1) && (errno != EINTR)) break;
551 if (child == svd[0].pid) {
552 svd[0].pid = 0;
553 pidchanged = 1;
554 svd[0].ctrl &=~C_TERM;
555 if (svd[0].state != S_FINISH)
556 fd = open_read("finish");
557 if (fd != -1) {
558 close(fd);
559 svd[0].state = S_FINISH;
560 update_status(&svd[0]);
561 continue;
562 }
563 svd[0].state = S_DOWN;
564 taia_uint(&deadline, 1);
565 taia_add(&deadline, &svd[0].start, &deadline);
566 taia_now(&svd[0].start);
567 update_status(&svd[0]);
568 if (taia_less(&svd[0].start, &deadline)) sleep(1);
569 }
570 if (haslog) {
571 if (child == svd[1].pid) {
572 svd[1].pid = 0;
573 pidchanged = 1;
574 svd[1].state = S_DOWN;
575 svd[1].ctrl &=~C_TERM;
576 taia_uint(&deadline, 1);
577 taia_add(&deadline, &svd[1].start, &deadline);
578 taia_now(&svd[1].start);
579 update_status(&svd[1]);
580 if (taia_less(&svd[1].start, &deadline)) sleep(1);
581 }
582 }
583 }
584 if (read(svd[0].fdcontrol, &ch, 1) == 1)
585 ctrl(&svd[0], ch);
586 if (haslog)
587 if (read(svd[1].fdcontrol, &ch, 1) == 1)
588 ctrl(&svd[1], ch);
589
590 if (sigterm) {
591 ctrl(&svd[0], 'x');
592 sigterm = 0;
593 }
594
595 if (svd[0].want == W_EXIT && svd[0].state == S_DOWN) {
596 if (svd[1].pid == 0)
597 _exit(0);
598 if (svd[1].want != W_EXIT) {
599 svd[1].want = W_EXIT;
600 /* stopservice(&svd[1]); */
601 update_status(&svd[1]);
602 close(logpipe[1]);
603 close(logpipe[0]);
604 //if (close(logpipe[1]) == -1)
605 // warn_cannot("close logpipe[1]");
606 //if (close(logpipe[0]) == -1)
607 // warn_cannot("close logpipe[0]");
608 }
609 }
610 }
611 /* not reached */
612 return 0;
613}
generated by cgit v1.2.3-55-g6feb (git 2.39.1) at 2025-08-13 16:55:14 +0000