source: tools/start-stop-daemon/start-stop-daemon.c@ 75

Last change on this file since 75 was 33, checked in by alloc, 10 years ago

SSD with more defines
File size: 33.9 KB
RevLine 
[2]1/*
2 * A rewrite of the original Debian's start-stop-daemon Perl script
3 * in C (faster - it is executed many times during system startup).
4 *
5 * Written by Marek Michalkiewicz <marekm@i17linuxb.ists.pwr.wroc.pl>,
6 * public domain. Based conceptually on start-stop-daemon.pl, by Ian
7 * Jackson <ijackson@gnu.ai.mit.edu>. May be used and distributed
8 * freely for any purpose. Changes by Christian Schwarz
9 * <schwarz@monet.m.isar.de>, to make output conform to the Debian
10 * Console Message Standard, also placed in public domain. Minor
11 * changes by Klee Dienes <klee@debian.org>, also placed in the Public
12 * Domain.
13 *
14 * Changes by Ben Collins <bcollins@debian.org>, added --chuid, --background
15 * and --make-pidfile options, placed in public domain as well.
16 *
17 * Port to OpenBSD by Sontri Tomo Huynh <huynh.29@osu.edu>
18 * and Andreas Schuldei <andreas@schuldei.org>
19 *
20 * Changes by Ian Jackson: added --retry (and associated rearrangements).
21 */
22
23/*
24 * MODIFIED TO NOT DEPEND ON EXTERNAL HEADERS!
25 * By Christian Illy <christian@illy.bz>
26 * Used dpkg source package from https://packages.debian.org/stable/dpkg
27 * Version 1.16.14
28 */
29
30// from config.h, generated by configure:
31#define VERSION "1.16.14_01"
32
33//*****************************************
34// Stuff from dpkg/macros.h
35#define DPKG_ATTR_NORET
36#define DPKG_ATTR_PRINTF(n)
37/**
38 * @def array_count
39 *
40 * Returns the amount of items in an array.
41 */
42#ifndef array_count
43#define array_count(a) (sizeof(a) / sizeof((a)[0]))
44#endif
45// End of stuff from dpkg/macros.h
46//*****************************************
47
[33]48//*****************************************
49// Required on some systems to get O_NOFOLLOW:
50#define _POSIX_C_SOURCE 200809L
51#define _GNU_SOURCE
52//*****************************************
[2]53
[33]54
[2]55#define OSLinux
56
57#define MIN_POLL_INTERVAL 20000 /* µs */
58
59#include <sys/syscall.h>
60
61#include <sys/types.h>
62#include <sys/time.h>
63#include <sys/stat.h>
64#include <sys/ioctl.h>
65#include <sys/termios.h>
66
67#include <assert.h>
68#include <errno.h>
69#include <limits.h>
70#include <fcntl.h>
71#include <dirent.h>
72#include <ctype.h>
73#include <string.h>
74#include <pwd.h>
75#include <grp.h>
76#include <signal.h>
77#include <unistd.h>
78#include <stddef.h>
79#include <stdbool.h>
80#include <stdarg.h>
81#include <stdlib.h>
82#include <stdio.h>
83#include <getopt.h>
84
85#include <error.h>
86
87#ifdef _POSIX_PRIORITY_SCHEDULING
88#include <sched.h>
89#else
90#define SCHED_OTHER -1
91#define SCHED_FIFO -1
92#define SCHED_RR -1
93#endif
94
95/* This comes from TASK_COMM_LEN defined in Linux' include/linux/sched.h. */
96#define PROCESS_NAME_SIZE 15
97
98#if defined(SYS_ioprio_set)
99#define HAVE_IOPRIO_SET
100#endif
101
102enum {
103 IOPRIO_WHO_PROCESS = 1,
104 IOPRIO_WHO_PGRP,
105 IOPRIO_WHO_USER,
106};
107
108enum {
109 IOPRIO_CLASS_NONE,
110 IOPRIO_CLASS_RT,
111 IOPRIO_CLASS_BE,
112 IOPRIO_CLASS_IDLE,
113};
114
115enum action_code {
116 action_none,
117 action_start,
118 action_stop,
119 action_status,
120};
121
122static enum action_code action;
123static int testmode = 0;
124static int quietmode = 0;
125static int exitnodo = 1;
126static int background = 0;
127static int close_io = 1;
128static int mpidfile = 0;
129static int signal_nr = SIGTERM;
130static int user_id = -1;
131static int runas_uid = -1;
132static int runas_gid = -1;
133static const char *userspec = NULL;
134static char *changeuser = NULL;
135static const char *changegroup = NULL;
136static char *changeroot = NULL;
137static const char *changedir = "/";
138static const char *cmdname = NULL;
139static char *execname = NULL;
140static char *startas = NULL;
141static const char *pidfile = NULL;
142static char what_stop[1024];
143static const char *progname = "";
144static int nicelevel = 0;
145static int umask_value = -1;
146
147#define IOPRIO_CLASS_SHIFT 13
148#define IOPRIO_PRIO_VALUE(class, prio) (((class) << IOPRIO_CLASS_SHIFT) | (prio))
149#define IO_SCHED_PRIO_MIN 0
150#define IO_SCHED_PRIO_MAX 7
151
152static struct stat exec_stat;
153
154/* LSB Init Script process status exit codes. */
155enum status_code {
156 status_ok = 0,
157 status_dead_pidfile = 1,
158 status_dead_lockfile = 2,
159 status_dead = 3,
160 status_unknown = 4,
161};
162
163struct pid_list {
164 struct pid_list *next;
165 pid_t pid;
166};
167
168static struct pid_list *found = NULL;
169static struct pid_list *killed = NULL;
170
171/* Resource scheduling policy. */
172struct res_schedule {
173 const char *policy_name;
174 int policy;
175 int priority;
176};
177
178struct schedule_item {
179 enum {
180 sched_timeout,
181 sched_signal,
182 sched_goto,
183 /* Only seen within parse_schedule and callees. */
184 sched_forever,
185 } type;
186 /* Seconds, signal no., or index into array. */
187 int value;
188};
189
190static struct res_schedule *proc_sched = NULL;
191static struct res_schedule *io_sched = NULL;
192
193static int schedule_length;
194static struct schedule_item *schedule = NULL;
195
196
197static void DPKG_ATTR_PRINTF(1)
198warning(const char *format, ...)
199{
200 va_list arglist;
201
202 fprintf(stderr, "%s: warning: ", progname);
203 va_start(arglist, format);
204 vfprintf(stderr, format, arglist);
205 va_end(arglist);
206}
207
208static void DPKG_ATTR_NORET DPKG_ATTR_PRINTF(1)
209fatal(const char *format, ...)
210{
211 va_list arglist;
212 int errno_fatal = errno;
213
214 fprintf(stderr, "%s: ", progname);
215 va_start(arglist, format);
216 vfprintf(stderr, format, arglist);
217 va_end(arglist);
218 if (errno_fatal)
219 fprintf(stderr, " (%s)\n", strerror(errno_fatal));
220 else
221 fprintf(stderr, "\n");
222
223 if (action == action_status)
224 exit(status_unknown);
225 else
226 exit(2);
227}
228
229static void *
230xmalloc(int size)
231{
232 void *ptr;
233
234 ptr = malloc(size);
235 if (ptr)
236 return ptr;
237 fatal("malloc(%d) failed", size);
238}
239
240static char *
241xstrdup(const char *str)
242{
243 char *new_str;
244
245 new_str = strdup(str);
246 if (new_str)
247 return new_str;
248 fatal("strdup(%s) failed", str);
249}
250
251static void
252xgettimeofday(struct timeval *tv)
253{
254 if (gettimeofday(tv, NULL) != 0)
255 fatal("gettimeofday failed");
256}
257
258static void
259tmul(struct timeval *a, int b)
260{
261 a->tv_sec *= b;
262 a->tv_usec *= b;
263 a->tv_sec = a->tv_sec + a->tv_usec / 1000000;
264 a->tv_usec %= 1000000;
265}
266
267static char *
268newpath(const char *dirname, const char *filename)
269{
270 char *path;
271 size_t path_len;
272
273 path_len = strlen(dirname) + 1 + strlen(filename) + 1;
274 path = xmalloc(path_len);
275 snprintf(path, path_len, "%s/%s", dirname, filename);
276
277 return path;
278}
279
280static long
281get_open_fd_max(void)
282{
283 return getdtablesize();
284}
285
286static void
287daemonize(void)
288{
289 pid_t pid;
290
291 if (quietmode < 0)
292 printf("Detaching to start %s...", startas);
293
294 pid = fork();
295 if (pid < 0)
296 fatal("unable to do first fork");
297 else if (pid) /* Parent. */
298 _exit(0);
299
300 /* Create a new session. */
301 setsid();
302
303 pid = fork();
304 if (pid < 0)
305 fatal("unable to do second fork");
306 else if (pid) /* Parent. */
307 _exit(0);
308
309 if (quietmode < 0)
310 printf("done.\n");
311}
312
313static void
314write_pidfile(const char *filename, pid_t pid)
315{
316 FILE *fp;
317 int fd;
318
319 fd = open(filename, O_CREAT | O_WRONLY | O_TRUNC | O_NOFOLLOW, 0666);
320 if (fd < 0)
321 fp = NULL;
322 else
323 fp = fdopen(fd, "w");
324
325 if (fp == NULL)
326 fatal("unable to open pidfile '%s' for writing", filename);
327
328 fprintf(fp, "%d\n", pid);
329
330 if (fclose(fp))
331 fatal("unable to close pidfile '%s'", filename);
332}
333
334static void
335pid_list_push(struct pid_list **list, pid_t pid)
336{
337 struct pid_list *p;
338
339 p = xmalloc(sizeof(*p));
340 p->next = *list;
341 p->pid = pid;
342 *list = p;
343}
344
345static void
346pid_list_free(struct pid_list **list)
347{
348 struct pid_list *here, *next;
349
350 for (here = *list; here != NULL; here = next) {
351 next = here->next;
352 free(here);
353 }
354
355 *list = NULL;
356}
357
358static void
359usage(void)
360{
361 printf(
362"Usage: start-stop-daemon [<option> ...] <command>\n"
363"\n"
364"Commands:\n"
365" -S|--start -- <argument> ... start a program and pass <arguments> to it\n"
366" -K|--stop stop a program\n"
367" -T|--status get the program status\n"
368" -H|--help print help information\n"
369" -V|--version print version\n"
370"\n"
371"Matching options (at least one is required):\n"
372" -p|--pidfile <pid-file> pid file to check\n"
373" -x|--exec <executable> program to start/check if it is running\n"
374" -n|--name <process-name> process name to check\n"
375" -u|--user <username|uid> process owner to check\n"
376"\n"
377"Options:\n"
378" -g|--group <group|gid> run process as this group\n"
379" -c|--chuid <name|uid[:group|gid]>\n"
380" change to this user/group before starting\n"
381" process\n"
382" -s|--signal <signal> signal to send (default TERM)\n"
383" -a|--startas <pathname> program to start (default is <executable>)\n"
384" -r|--chroot <directory> chroot to <directory> before starting\n"
385" -d|--chdir <directory> change to <directory> (default is /)\n"
386" -N|--nicelevel <incr> add incr to the process' nice level\n"
387" -P|--procsched <policy[:prio]>\n"
388" use <policy> with <prio> for the kernel\n"
389" process scheduler (default prio is 0)\n"
390" -I|--iosched <class[:prio]> use <class> with <prio> to set the IO\n"
391" scheduler (default prio is 4)\n"
392" -k|--umask <mask> change the umask to <mask> before starting\n"
393" -b|--background force the process to detach\n"
394" -C|--no-close do not close any file descriptor\n"
395" -m|--make-pidfile create the pidfile before starting\n"
396" -R|--retry <schedule> check whether processes die, and retry\n"
397" -t|--test test mode, don't do anything\n"
398" -o|--oknodo exit status 0 (not 1) if nothing done\n"
399" -q|--quiet be more quiet\n"
400" -v|--verbose be more verbose\n"
401"\n"
402"Retry <schedule> is <item>|/<item>/... where <item> is one of\n"
403" -<signal-num>|[-]<signal-name> send that signal\n"
404" <timeout> wait that many seconds\n"
405" forever repeat remainder forever\n"
406"or <schedule> may be just <timeout>, meaning <signal>/<timeout>/KILL/<timeout>\n"
407"\n"
408"The process scheduler <policy> can be one of:\n"
409" other, fifo or rr\n"
410"\n"
411"The IO scheduler <class> can be one of:\n"
412" real-time, best-effort or idle\n"
413"\n"
414"Exit status:\n"
415" 0 = done\n"
416" 1 = nothing done (=> 0 if --oknodo)\n"
417" 2 = with --retry, processes would not die\n"
418" 3 = trouble\n"
419"Exit status with --status:\n"
420" 0 = program is running\n"
421" 1 = program is not running and the pid file exists\n"
422" 3 = program is not running\n"
423" 4 = unable to determine status\n");
424}
425
426static void
427do_version(void)
428{
429 printf("start-stop-daemon %s for non-Debian\n\n", VERSION);
430
431 printf("Written by Marek Michalkiewicz, public domain.\n");
432}
433
434static void DPKG_ATTR_NORET
435badusage(const char *msg)
436{
437 if (msg)
438 fprintf(stderr, "%s: %s\n", progname, msg);
439 fprintf(stderr, "Try '%s --help' for more information.\n", progname);
440
441 if (action == action_status)
442 exit(status_unknown);
443 else
444 exit(3);
445}
446
447struct sigpair {
448 const char *name;
449 int signal;
450};
451
452static const struct sigpair siglist[] = {
453 { "ABRT", SIGABRT },
454 { "ALRM", SIGALRM },
455 { "FPE", SIGFPE },
456 { "HUP", SIGHUP },
457 { "ILL", SIGILL },
458 { "INT", SIGINT },
459 { "KILL", SIGKILL },
460 { "PIPE", SIGPIPE },
461 { "QUIT", SIGQUIT },
462 { "SEGV", SIGSEGV },
463 { "TERM", SIGTERM },
464 { "USR1", SIGUSR1 },
465 { "USR2", SIGUSR2 },
466 { "CHLD", SIGCHLD },
467 { "CONT", SIGCONT },
468 { "STOP", SIGSTOP },
469 { "TSTP", SIGTSTP },
470 { "TTIN", SIGTTIN },
471 { "TTOU", SIGTTOU }
472};
473
474static int
475parse_unsigned(const char *string, int base, int *value_r)
476{
477 long value;
478 char *endptr;
479
480 if (!string[0])
481 return -1;
482
483 errno = 0;
484 value = strtol(string, &endptr, base);
485 if (string == endptr || *endptr != '\0' || errno != 0)
486 return -1;
487 if (value < 0 || value > INT_MAX)
488 return -1;
489
490 *value_r = value;
491 return 0;
492}
493
494static int
495parse_signal(const char *sig_str, int *sig_num)
496{
497 unsigned int i;
498
499 if (parse_unsigned(sig_str, 10, sig_num) == 0)
500 return 0;
501
502 for (i = 0; i < array_count(siglist); i++) {
503 if (strcmp(sig_str, siglist[i].name) == 0) {
504 *sig_num = siglist[i].signal;
505 return 0;
506 }
507 }
508 return -1;
509}
510
511static int
512parse_umask(const char *string, int *value_r)
513{
514 return parse_unsigned(string, 0, value_r);
515}
516
517static void
518validate_proc_schedule(void)
519{
520#ifdef _POSIX_PRIORITY_SCHEDULING
521 int prio_min, prio_max;
522
523 prio_min = sched_get_priority_min(proc_sched->policy);
524 prio_max = sched_get_priority_max(proc_sched->policy);
525
526 if (proc_sched->priority < prio_min)
527 badusage("process scheduler priority less than min");
528 if (proc_sched->priority > prio_max)
529 badusage("process scheduler priority greater than max");
530#endif
531}
532
533static void
534parse_proc_schedule(const char *string)
535{
536 char *policy_str, *prio_str;
537 int prio = 0;
538
539 policy_str = xstrdup(string);
540 policy_str = strtok(policy_str, ":");
541 prio_str = strtok(NULL, ":");
542
543 if (prio_str && parse_unsigned(prio_str, 10, &prio) != 0)
544 fatal("invalid process scheduler priority");
545
546 proc_sched = xmalloc(sizeof(*proc_sched));
547 proc_sched->policy_name = policy_str;
548
549 if (strcmp(policy_str, "other") == 0) {
550 proc_sched->policy = SCHED_OTHER;
551 proc_sched->priority = 0;
552 } else if (strcmp(policy_str, "fifo") == 0) {
553 proc_sched->policy = SCHED_FIFO;
554 proc_sched->priority = prio;
555 } else if (strcmp(policy_str, "rr") == 0) {
556 proc_sched->policy = SCHED_RR;
557 proc_sched->priority = prio;
558 } else
559 badusage("invalid process scheduler policy");
560
561 validate_proc_schedule();
562}
563
564static void
565parse_io_schedule(const char *string)
566{
567 char *class_str, *prio_str;
568 int prio = 4;
569
570 class_str = xstrdup(string);
571 class_str = strtok(class_str, ":");
572 prio_str = strtok(NULL, ":");
573
574 if (prio_str && parse_unsigned(prio_str, 10, &prio) != 0)
575 fatal("invalid IO scheduler priority");
576
577 io_sched = xmalloc(sizeof(*io_sched));
578 io_sched->policy_name = class_str;
579
580 if (strcmp(class_str, "real-time") == 0) {
581 io_sched->policy = IOPRIO_CLASS_RT;
582 io_sched->priority = prio;
583 } else if (strcmp(class_str, "best-effort") == 0) {
584 io_sched->policy = IOPRIO_CLASS_BE;
585 io_sched->priority = prio;
586 } else if (strcmp(class_str, "idle") == 0) {
587 io_sched->policy = IOPRIO_CLASS_IDLE;
588 io_sched->priority = 7;
589 } else
590 badusage("invalid IO scheduler policy");
591
592 if (io_sched->priority < IO_SCHED_PRIO_MIN)
593 badusage("IO scheduler priority less than min");
594 if (io_sched->priority > IO_SCHED_PRIO_MAX)
595 badusage("IO scheduler priority greater than max");
596}
597
598static void
599set_proc_schedule(struct res_schedule *sched)
600{
601#ifdef _POSIX_PRIORITY_SCHEDULING
602 struct sched_param param;
603
604 param.sched_priority = sched->priority;
605
606 if (sched_setscheduler(getpid(), sched->policy, &param) == -1)
607 fatal("unable to set process scheduler");
608#endif
609}
610
611#ifdef HAVE_IOPRIO_SET
612static inline int
613ioprio_set(int which, int who, int ioprio)
614{
615 return syscall(SYS_ioprio_set, which, who, ioprio);
616}
617#endif
618
619static void
620set_io_schedule(struct res_schedule *sched)
621{
622#ifdef HAVE_IOPRIO_SET
623 int io_sched_mask;
624
625 io_sched_mask = IOPRIO_PRIO_VALUE(sched->policy, sched->priority);
626 if (ioprio_set(IOPRIO_WHO_PROCESS, getpid(), io_sched_mask) == -1)
627 warning("unable to alter IO priority to mask %i (%s)\n",
628 io_sched_mask, strerror(errno));
629#endif
630}
631
632static void
633parse_schedule_item(const char *string, struct schedule_item *item)
634{
635 const char *after_hyph;
636
637 if (strcmp(string, "forever") == 0) {
638 item->type = sched_forever;
639 } else if (isdigit(string[0])) {
640 item->type = sched_timeout;
641 if (parse_unsigned(string, 10, &item->value) != 0)
642 badusage("invalid timeout value in schedule");
643 } else if ((after_hyph = string + (string[0] == '-')) &&
644 parse_signal(after_hyph, &item->value) == 0) {
645 item->type = sched_signal;
646 } else {
647 badusage("invalid schedule item (must be [-]<signal-name>, "
648 "-<signal-number>, <timeout> or 'forever'");
649 }
650}
651
652static void
653parse_schedule(const char *schedule_str)
654{
655 char item_buf[20];
656 const char *slash;
657 int count, repeatat;
658 size_t str_len;
659
660 count = 0;
661 for (slash = schedule_str; *slash; slash++)
662 if (*slash == '/')
663 count++;
664
665 schedule_length = (count == 0) ? 4 : count + 1;
666 schedule = xmalloc(sizeof(*schedule) * schedule_length);
667
668 if (count == 0) {
669 schedule[0].type = sched_signal;
670 schedule[0].value = signal_nr;
671 parse_schedule_item(schedule_str, &schedule[1]);
672 if (schedule[1].type != sched_timeout) {
673 badusage ("--retry takes timeout, or schedule list"
674 " of at least two items");
675 }
676 schedule[2].type = sched_signal;
677 schedule[2].value = SIGKILL;
678 schedule[3] = schedule[1];
679 } else {
680 count = 0;
681 repeatat = -1;
682 while (schedule_str != NULL) {
683 slash = strchr(schedule_str, '/');
684 str_len = slash ? (size_t)(slash - schedule_str) : strlen(schedule_str);
685 if (str_len >= sizeof(item_buf))
686 badusage("invalid schedule item: far too long"
687 " (you must delimit items with slashes)");
688 memcpy(item_buf, schedule_str, str_len);
689 item_buf[str_len] = '\0';
690 schedule_str = slash ? slash + 1 : NULL;
691
692 parse_schedule_item(item_buf, &schedule[count]);
693 if (schedule[count].type == sched_forever) {
694 if (repeatat >= 0)
695 badusage("invalid schedule: 'forever'"
696 " appears more than once");
697 repeatat = count;
698 continue;
699 }
700 count++;
701 }
702 if (repeatat == count)
703 badusage("invalid schedule: 'forever' appears last, "
704 "nothing to repeat");
705 if (repeatat >= 0) {
706 schedule[count].type = sched_goto;
707 schedule[count].value = repeatat;
708 count++;
709 }
710 assert(count == schedule_length);
711 }
712}
713
714static void
715set_action(enum action_code new_action)
716{
717 if (action == new_action)
718 return;
719
720 if (action != action_none)
721 badusage("only one command can be specified");
722
723 action = new_action;
724}
725
726static void
727parse_options(int argc, char * const *argv)
728{
729 static struct option longopts[] = {
730 { "help", 0, NULL, 'H'},
731 { "stop", 0, NULL, 'K'},
732 { "start", 0, NULL, 'S'},
733 { "status", 0, NULL, 'T'},
734 { "version", 0, NULL, 'V'},
735 { "startas", 1, NULL, 'a'},
736 { "name", 1, NULL, 'n'},
737 { "oknodo", 0, NULL, 'o'},
738 { "pidfile", 1, NULL, 'p'},
739 { "quiet", 0, NULL, 'q'},
740 { "signal", 1, NULL, 's'},
741 { "test", 0, NULL, 't'},
742 { "user", 1, NULL, 'u'},
743 { "group", 1, NULL, 'g'},
744 { "chroot", 1, NULL, 'r'},
745 { "verbose", 0, NULL, 'v'},
746 { "exec", 1, NULL, 'x'},
747 { "chuid", 1, NULL, 'c'},
748 { "nicelevel", 1, NULL, 'N'},
749 { "procsched", 1, NULL, 'P'},
750 { "iosched", 1, NULL, 'I'},
751 { "umask", 1, NULL, 'k'},
752 { "background", 0, NULL, 'b'},
753 { "no-close", 0, NULL, 'C'},
754 { "make-pidfile", 0, NULL, 'm'},
755 { "retry", 1, NULL, 'R'},
756 { "chdir", 1, NULL, 'd'},
757 { NULL, 0, NULL, 0 }
758 };
759 const char *umask_str = NULL;
760 const char *signal_str = NULL;
761 const char *schedule_str = NULL;
762 const char *proc_schedule_str = NULL;
763 const char *io_schedule_str = NULL;
764 int c;
765
766 for (;;) {
767 c = getopt_long(argc, argv,
768 "HKSVTa:n:op:qr:s:tu:vx:c:N:P:I:k:bCmR:g:d:",
769 longopts, NULL);
770 if (c == -1)
771 break;
772 switch (c) {
773 case 'H': /* --help */
774 usage();
775 exit(0);
776 case 'K': /* --stop */
777 set_action(action_stop);
778 break;
779 case 'S': /* --start */
780 set_action(action_start);
781 break;
782 case 'T': /* --status */
783 set_action(action_status);
784 break;
785 case 'V': /* --version */
786 do_version();
787 exit(0);
788 case 'a': /* --startas <pathname> */
789 startas = optarg;
790 break;
791 case 'n': /* --name <process-name> */
792 cmdname = optarg;
793 break;
794 case 'o': /* --oknodo */
795 exitnodo = 0;
796 break;
797 case 'p': /* --pidfile <pid-file> */
798 pidfile = optarg;
799 break;
800 case 'q': /* --quiet */
801 quietmode = 1;
802 break;
803 case 's': /* --signal <signal> */
804 signal_str = optarg;
805 break;
806 case 't': /* --test */
807 testmode = 1;
808 break;
809 case 'u': /* --user <username>|<uid> */
810 userspec = optarg;
811 break;
812 case 'v': /* --verbose */
813 quietmode = -1;
814 break;
815 case 'x': /* --exec <executable> */
816 execname = optarg;
817 break;
818 case 'c': /* --chuid <username>|<uid> */
819 /* We copy the string just in case we need the
820 * argument later. */
821 changeuser = xstrdup(optarg);
822 changeuser = strtok(changeuser, ":");
823 changegroup = strtok(NULL, ":");
824 break;
825 case 'g': /* --group <group>|<gid> */
826 changegroup = optarg;
827 break;
828 case 'r': /* --chroot /new/root */
829 changeroot = optarg;
830 break;
831 case 'N': /* --nice */
832 nicelevel = atoi(optarg);
833 break;
834 case 'P': /* --procsched */
835 proc_schedule_str = optarg;
836 break;
837 case 'I': /* --iosched */
838 io_schedule_str = optarg;
839 break;
840 case 'k': /* --umask <mask> */
841 umask_str = optarg;
842 break;
843 case 'b': /* --background */
844 background = 1;
845 break;
846 case 'C': /* --no-close */
847 close_io = 0;
848 break;
849 case 'm': /* --make-pidfile */
850 mpidfile = 1;
851 break;
852 case 'R': /* --retry <schedule>|<timeout> */
853 schedule_str = optarg;
854 break;
855 case 'd': /* --chdir /new/dir */
856 changedir = optarg;
857 break;
858 default:
859 /* Message printed by getopt. */
860 badusage(NULL);
861 }
862 }
863
864 if (signal_str != NULL) {
865 if (parse_signal(signal_str, &signal_nr) != 0)
866 badusage("signal value must be numeric or name"
867 " of signal (KILL, INT, ...)");
868 }
869
870 if (schedule_str != NULL) {
871 parse_schedule(schedule_str);
872 }
873
874 if (proc_schedule_str != NULL)
875 parse_proc_schedule(proc_schedule_str);
876
877 if (io_schedule_str != NULL)
878 parse_io_schedule(io_schedule_str);
879
880 if (umask_str != NULL) {
881 if (parse_umask(umask_str, &umask_value) != 0)
882 badusage("umask value must be a positive number");
883 }
884
885 if (action == action_none)
886 badusage("need one of --start or --stop or --status");
887
888 if (!execname && !pidfile && !userspec && !cmdname)
889 badusage("need at least one of --exec, --pidfile, --user or --name");
890
891 if (cmdname && strlen(cmdname) > PROCESS_NAME_SIZE)
892 warning("this system is not able to track process names\n"
893 "longer than %d characters, please use --exec "
894 "instead of --name.\n", PROCESS_NAME_SIZE);
895
896 if (!startas)
897 startas = execname;
898
899 if (action == action_start && !startas)
900 badusage("--start needs --exec or --startas");
901
902 if (mpidfile && pidfile == NULL)
903 badusage("--make-pidfile requires --pidfile");
904
905 if (background && action != action_start)
906 badusage("--background is only relevant with --start");
907
908 if (!close_io && !background)
909 badusage("--no-close is only relevant with --background");
910}
911
912static bool
913pid_is_exec(pid_t pid, const struct stat *esb)
914{
915 char lname[32];
916 char lcontents[_POSIX_PATH_MAX];
917 const char deleted[] = " (deleted)";
918 int nread;
919 struct stat sb;
920
921 sprintf(lname, "/proc/%d/exe", pid);
922 nread = readlink(lname, lcontents, sizeof(lcontents));
923 if (nread == -1)
924 return false;
925
926 lcontents[nread] = '\0';
927 if (strcmp(lcontents + nread - strlen(deleted), deleted) == 0)
928 lcontents[nread - strlen(deleted)] = '\0';
929
930 if (stat(lcontents, &sb) != 0)
931 return false;
932
933 return (sb.st_dev == esb->st_dev && sb.st_ino == esb->st_ino);
934}
935
936static bool
937pid_is_user(pid_t pid, uid_t uid)
938{
939 struct stat sb;
940 char buf[32];
941
942 sprintf(buf, "/proc/%d", pid);
943 if (stat(buf, &sb) != 0)
944 return false;
945 return (sb.st_uid == uid);
946}
947
948static bool
949pid_is_cmd(pid_t pid, const char *name)
950{
951 char buf[32];
952 FILE *f;
953 int c;
954
955 sprintf(buf, "/proc/%d/stat", pid);
956 f = fopen(buf, "r");
957 if (!f)
958 return false;
959 while ((c = getc(f)) != EOF && c != '(')
960 ;
961 if (c != '(') {
962 fclose(f);
963 return false;
964 }
965 /* This hopefully handles command names containing ‘)’. */
966 while ((c = getc(f)) != EOF && c == *name)
967 name++;
968 fclose(f);
969 return (c == ')' && *name == '\0');
970}
971
972static bool
973pid_is_running(pid_t pid)
974{
975 if (kill(pid, 0) == 0 || errno == EPERM)
976 return true;
977 else if (errno == ESRCH)
978 return false;
979 else
980 fatal("error checking pid %u status", pid);
981}
982
983static enum status_code
984pid_check(pid_t pid)
985{
986 if (execname && !pid_is_exec(pid, &exec_stat))
987 return status_dead;
988 if (userspec && !pid_is_user(pid, user_id))
989 return status_dead;
990 if (cmdname && !pid_is_cmd(pid, cmdname))
991 return status_dead;
992 if (action != action_stop && !pid_is_running(pid))
993 return status_dead;
994
995 pid_list_push(&found, pid);
996
997 return status_ok;
998}
999
1000static enum status_code
1001do_pidfile(const char *name)
1002{
1003 FILE *f;
1004 static pid_t pid = 0;
1005
1006 if (pid)
1007 return pid_check(pid);
1008
1009 f = fopen(name, "r");
1010 if (f) {
1011 enum status_code pid_status;
1012
1013 if (fscanf(f, "%d", &pid) == 1)
1014 pid_status = pid_check(pid);
1015 else
1016 pid_status = status_unknown;
1017 fclose(f);
1018
1019 if (pid_status == status_dead)
1020 return status_dead_pidfile;
1021 else
1022 return pid_status;
1023 } else if (errno == ENOENT)
1024 return status_dead;
1025 else
1026 fatal("unable to open pidfile %s", name);
1027}
1028
1029static enum status_code
1030do_procinit(void)
1031{
1032 DIR *procdir;
1033 struct dirent *entry;
1034 int foundany;
1035 pid_t pid;
1036 enum status_code prog_status = status_dead;
1037
1038 procdir = opendir("/proc");
1039 if (!procdir)
1040 fatal("unable to opendir /proc");
1041
1042 foundany = 0;
1043 while ((entry = readdir(procdir)) != NULL) {
1044 enum status_code pid_status;
1045
1046 if (sscanf(entry->d_name, "%d", &pid) != 1)
1047 continue;
1048 foundany++;
1049
1050 pid_status = pid_check(pid);
1051 if (pid_status < prog_status)
1052 prog_status = pid_status;
1053 }
1054 closedir(procdir);
1055 if (!foundany)
1056 fatal("nothing in /proc - not mounted?");
1057
1058 return prog_status;
1059}
1060
1061static enum status_code
1062do_findprocs(void)
1063{
1064 pid_list_free(&found);
1065
1066 if (pidfile)
1067 return do_pidfile(pidfile);
1068 else
1069 return do_procinit();
1070}
1071
1072static void
1073do_stop(int sig_num, int *n_killed, int *n_notkilled)
1074{
1075 struct pid_list *p;
1076
1077 do_findprocs();
1078
1079 *n_killed = 0;
1080 *n_notkilled = 0;
1081
1082 if (!found)
1083 return;
1084
1085 pid_list_free(&killed);
1086
1087 for (p = found; p; p = p->next) {
1088 if (testmode) {
1089 if (quietmode <= 0)
1090 printf("Would send signal %d to %d.\n",
1091 sig_num, p->pid);
1092 (*n_killed)++;
1093 } else if (kill(p->pid, sig_num) == 0) {
1094 pid_list_push(&killed, p->pid);
1095 (*n_killed)++;
1096 } else {
1097 if (sig_num)
1098 warning("failed to kill %d: %s\n",
1099 p->pid, strerror(errno));
1100 (*n_notkilled)++;
1101 }
1102 }
1103}
1104
1105static void
1106do_stop_summary(int retry_nr)
1107{
1108 struct pid_list *p;
1109
1110 if (quietmode >= 0 || !killed)
1111 return;
1112
1113 printf("Stopped %s (pid", what_stop);
1114 for (p = killed; p; p = p->next)
1115 printf(" %d", p->pid);
1116 putchar(')');
1117 if (retry_nr > 0)
1118 printf(", retry #%d", retry_nr);
1119 printf(".\n");
1120}
1121
1122static void
1123set_what_stop(const char *str)
1124{
1125 strncpy(what_stop, str, sizeof(what_stop));
1126 what_stop[sizeof(what_stop) - 1] = '\0';
1127}
1128
1129/*
1130 * We want to keep polling for the processes, to see if they've exited, or
1131 * until the timeout expires.
1132 *
1133 * This is a somewhat complicated algorithm to try to ensure that we notice
1134 * reasonably quickly when all the processes have exited, but don't spend
1135 * too much CPU time polling. In particular, on a fast machine with
1136 * quick-exiting daemons we don't want to delay system shutdown too much,
1137 * whereas on a slow one, or where processes are taking some time to exit,
1138 * we want to increase the polling interval.
1139 *
1140 * The algorithm is as follows: we measure the elapsed time it takes to do
1141 * one poll(), and wait a multiple of this time for the next poll. However,
1142 * if that would put us past the end of the timeout period we wait only as
1143 * long as the timeout period, but in any case we always wait at least
1144 * MIN_POLL_INTERVAL (20ms). The multiple (‘ratio’) starts out as 2, and
1145 * increases by 1 for each poll to a maximum of 10; so we use up to between
1146 * 30% and 10% of the machine's resources (assuming a few reasonable things
1147 * about system performance).
1148 */
1149static bool
1150do_stop_timeout(int timeout, int *n_killed, int *n_notkilled)
1151{
1152 struct timeval stopat, before, after, interval, maxinterval;
1153 int r, ratio;
1154
1155 xgettimeofday(&stopat);
1156 stopat.tv_sec += timeout;
1157 ratio = 1;
1158 for (;;) {
1159 xgettimeofday(&before);
1160 if (timercmp(&before, &stopat, >))
1161 return false;
1162
1163 do_stop(0, n_killed, n_notkilled);
1164 if (!*n_killed)
1165 return true;
1166
1167 xgettimeofday(&after);
1168
1169 if (!timercmp(&after, &stopat, <))
1170 return false;
1171
1172 if (ratio < 10)
1173 ratio++;
1174
1175 timersub(&stopat, &after, &maxinterval);
1176 timersub(&after, &before, &interval);
1177 tmul(&interval, ratio);
1178
1179 if (interval.tv_sec < 0 || interval.tv_usec < 0)
1180 interval.tv_sec = interval.tv_usec = 0;
1181
1182 if (timercmp(&interval, &maxinterval, >))
1183 interval = maxinterval;
1184
1185 if (interval.tv_sec == 0 &&
1186 interval.tv_usec <= MIN_POLL_INTERVAL)
1187 interval.tv_usec = MIN_POLL_INTERVAL;
1188
1189 r = select(0, NULL, NULL, NULL, &interval);
1190 if (r < 0 && errno != EINTR)
1191 fatal("select() failed for pause");
1192 }
1193}
1194
1195static int
1196finish_stop_schedule(bool anykilled)
1197{
1198 if (anykilled)
1199 return 0;
1200
1201 if (quietmode <= 0)
1202 printf("No %s found running; none killed.\n", what_stop);
1203
1204 return exitnodo;
1205}
1206
1207static int
1208run_stop_schedule(void)
1209{
1210 int position, n_killed, n_notkilled, value, retry_nr;
1211 bool anykilled;
1212
1213 if (testmode) {
1214 if (schedule != NULL) {
1215 if (quietmode <= 0)
1216 printf("Ignoring --retry in test mode\n");
1217 schedule = NULL;
1218 }
1219 }
1220
1221 if (cmdname)
1222 set_what_stop(cmdname);
1223 else if (execname)
1224 set_what_stop(execname);
1225 else if (pidfile)
1226 sprintf(what_stop, "process in pidfile '%.200s'", pidfile);
1227 else if (userspec)
1228 sprintf(what_stop, "process(es) owned by '%.200s'", userspec);
1229 else
1230 fatal("internal error, no match option, please report");
1231
1232 anykilled = false;
1233 retry_nr = 0;
1234
1235 if (schedule == NULL) {
1236 do_stop(signal_nr, &n_killed, &n_notkilled);
1237 do_stop_summary(0);
1238 if (n_notkilled > 0 && quietmode <= 0)
1239 printf("%d pids were not killed\n", n_notkilled);
1240 if (n_killed)
1241 anykilled = true;
1242 return finish_stop_schedule(anykilled);
1243 }
1244
1245 for (position = 0; position < schedule_length; position++) {
1246 reposition:
1247 value = schedule[position].value;
1248 n_notkilled = 0;
1249
1250 switch (schedule[position].type) {
1251 case sched_goto:
1252 position = value;
1253 goto reposition;
1254 case sched_signal:
1255 do_stop(value, &n_killed, &n_notkilled);
1256 do_stop_summary(retry_nr++);
1257 if (!n_killed)
1258 return finish_stop_schedule(anykilled);
1259 else
1260 anykilled = true;
1261 continue;
1262 case sched_timeout:
1263 if (do_stop_timeout(value, &n_killed, &n_notkilled))
1264 return finish_stop_schedule(anykilled);
1265 else
1266 continue;
1267 default:
1268 assert(!"schedule[].type value must be valid");
1269 }
1270 }
1271
1272 if (quietmode <= 0)
1273 printf("Program %s, %d process(es), refused to die.\n",
1274 what_stop, n_killed);
1275
1276 return 2;
1277}
1278
1279int
1280main(int argc, char **argv)
1281{
1282 enum status_code prog_status;
1283 int devnull_fd = -1;
1284 gid_t rgid;
1285 uid_t ruid;
1286 progname = argv[0];
1287
1288 parse_options(argc, argv);
1289 argc -= optind;
1290 argv += optind;
1291
1292 if (execname) {
1293 char *fullexecname;
1294
1295 /* If it's a relative path, normalize it. */
1296 if (execname[0] != '/')
1297 execname = newpath(changedir, execname);
1298
1299 if (changeroot)
1300 fullexecname = newpath(changeroot, execname);
1301 else
1302 fullexecname = execname;
1303
1304 if (stat(fullexecname, &exec_stat))
1305 fatal("unable to stat %s", fullexecname);
1306
1307 if (fullexecname != execname)
1308 free(fullexecname);
1309 }
1310
1311 if (userspec && sscanf(userspec, "%d", &user_id) != 1) {
1312 struct passwd *pw;
1313
1314 pw = getpwnam(userspec);
1315 if (!pw)
1316 fatal("user '%s' not found", userspec);
1317
1318 user_id = pw->pw_uid;
1319 }
1320
1321 if (changegroup && sscanf(changegroup, "%d", &runas_gid) != 1) {
1322 struct group *gr = getgrnam(changegroup);
1323 if (!gr)
1324 fatal("group '%s' not found", changegroup);
1325 changegroup = gr->gr_name;
1326 runas_gid = gr->gr_gid;
1327 }
1328 if (changeuser) {
1329 struct passwd *pw;
1330 struct stat st;
1331
1332 if (sscanf(changeuser, "%d", &runas_uid) == 1)
1333 pw = getpwuid(runas_uid);
1334 else
1335 pw = getpwnam(changeuser);
1336 if (!pw)
1337 fatal("user '%s' not found", changeuser);
1338 changeuser = pw->pw_name;
1339 runas_uid = pw->pw_uid;
1340 if (changegroup == NULL) {
1341 /* Pass the default group of this user. */
1342 changegroup = ""; /* Just empty. */
1343 runas_gid = pw->pw_gid;
1344 }
1345 if (stat(pw->pw_dir, &st) == 0)
1346 setenv("HOME", pw->pw_dir, 1);
1347 }
1348
1349 if (action == action_stop) {
1350 int i = run_stop_schedule();
1351 exit(i);
1352 }
1353
1354 prog_status = do_findprocs();
1355
1356 if (action == action_status)
1357 exit(prog_status);
1358
1359 if (found) {
1360 if (quietmode <= 0)
1361 printf("%s already running.\n", execname ? execname : "process");
1362 exit(exitnodo);
1363 }
1364 if (testmode && quietmode <= 0) {
1365 printf("Would start %s ", startas);
1366 while (argc-- > 0)
1367 printf("%s ", *argv++);
1368 if (changeuser != NULL) {
1369 printf(" (as user %s[%d]", changeuser, runas_uid);
1370 if (changegroup != NULL)
1371 printf(", and group %s[%d])", changegroup, runas_gid);
1372 else
1373 printf(")");
1374 }
1375 if (changeroot != NULL)
1376 printf(" in directory %s", changeroot);
1377 if (nicelevel)
1378 printf(", and add %i to the priority", nicelevel);
1379 if (proc_sched)
1380 printf(", with scheduling policy %s with priority %i",
1381 proc_sched->policy_name, proc_sched->priority);
1382 if (io_sched)
1383 printf(", with IO scheduling class %s with priority %i",
1384 io_sched->policy_name, io_sched->priority);
1385 printf(".\n");
1386 }
1387 if (testmode)
1388 exit(0);
1389 if (quietmode < 0)
1390 printf("Starting %s...\n", startas);
1391 *--argv = startas;
1392 if (background)
1393 /* Ok, we need to detach this process. */
1394 daemonize();
1395 if (background && close_io) {
1396 devnull_fd = open("/dev/null", O_RDWR);
1397 if (devnull_fd < 0)
1398 fatal("unable to open '%s'", "/dev/null");
1399 }
1400 if (nicelevel) {
1401 errno = 0;
1402 if ((nice(nicelevel) == -1) && (errno != 0))
1403 fatal("unable to alter nice level by %i", nicelevel);
1404 }
1405 if (proc_sched)
1406 set_proc_schedule(proc_sched);
1407 if (io_sched)
1408 set_io_schedule(io_sched);
1409 if (umask_value >= 0)
1410 umask(umask_value);
1411 if (mpidfile && pidfile != NULL)
1412 /* User wants _us_ to make the pidfile. */
1413 write_pidfile(pidfile, getpid());
1414 if (changeroot != NULL) {
1415 if (chdir(changeroot) < 0)
1416 fatal("unable to chdir() to %s", changeroot);
1417 if (chroot(changeroot) < 0)
1418 fatal("unable to chroot() to %s", changeroot);
1419 }
1420 if (chdir(changedir) < 0)
1421 fatal("unable to chdir() to %s", changedir);
1422
1423 rgid = getgid();
1424 ruid = getuid();
1425 if (changegroup != NULL) {
1426 if (rgid != (gid_t)runas_gid)
1427 if (setgid(runas_gid))
1428 fatal("unable to set gid to %d", runas_gid);
1429 }
1430 if (changeuser != NULL) {
1431 /* We assume that if our real user and group are the same as
1432 * the ones we should switch to, the supplementary groups
1433 * will be already in place. */
1434 if (rgid != (gid_t)runas_gid || ruid != (uid_t)runas_uid)
1435 if (initgroups(changeuser, runas_gid))
1436 fatal("unable to set initgroups() with gid %d",
1437 runas_gid);
1438
1439 if (ruid != (uid_t)runas_uid)
1440 if (setuid(runas_uid))
1441 fatal("unable to set uid to %s", changeuser);
1442 }
1443
1444 /* Set a default umask for dumb programs. */
1445 if (background && umask_value < 0)
1446 umask(022);
1447
1448 if (background && close_io) {
1449 int i;
1450
1451 dup2(devnull_fd, 0); /* stdin */
1452 dup2(devnull_fd, 1); /* stdout */
1453 dup2(devnull_fd, 2); /* stderr */
1454
1455 /* Now close all extra fds. */
1456 for (i = get_open_fd_max() - 1; i >= 3; --i)
1457 close(i);
1458 }
1459 execv(startas, argv);
1460 fatal("unable to start %s", startas);
1461}
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