chiark / gitweb /
main: introduce -D as quick acess to debugging
[elogind.git] / src / main.c
1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
2
3 /***
4   This file is part of systemd.
5
6   Copyright 2010 Lennart Poettering
7
8   systemd is free software; you can redistribute it and/or modify it
9   under the terms of the GNU General Public License as published by
10   the Free Software Foundation; either version 2 of the License, or
11   (at your option) any later version.
12
13   systemd is distributed in the hope that it will be useful, but
14   WITHOUT ANY WARRANTY; without even the implied warranty of
15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16   General Public License for more details.
17
18   You should have received a copy of the GNU General Public License
19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
20 ***/
21
22 #include <dbus/dbus.h>
23
24 #include <stdio.h>
25 #include <errno.h>
26 #include <string.h>
27 #include <unistd.h>
28 #include <sys/types.h>
29 #include <sys/stat.h>
30 #include <getopt.h>
31 #include <signal.h>
32 #include <sys/wait.h>
33 #include <fcntl.h>
34
35 #include "manager.h"
36 #include "log.h"
37 #include "mount-setup.h"
38 #include "hostname-setup.h"
39 #include "loopback-setup.h"
40 #include "kmod-setup.h"
41 #include "modprobe-setup.h"
42 #include "load-fragment.h"
43 #include "fdset.h"
44 #include "special.h"
45 #include "conf-parser.h"
46 #include "bus-errors.h"
47
48 static enum {
49         ACTION_RUN,
50         ACTION_HELP,
51         ACTION_TEST,
52         ACTION_DUMP_CONFIGURATION_ITEMS,
53         ACTION_DONE
54 } arg_action = ACTION_RUN;
55
56 static char *arg_default_unit = NULL;
57 static ManagerRunningAs arg_running_as = _MANAGER_RUNNING_AS_INVALID;
58
59 static bool arg_dump_core = true;
60 static bool arg_crash_shell = false;
61 static int arg_crash_chvt = -1;
62 static bool arg_confirm_spawn = false;
63 static bool arg_nomodules = false;
64 static bool arg_show_status = true;
65
66 static FILE* serialization = NULL;
67
68 _noreturn_ static void freeze(void) {
69         for (;;)
70                 pause();
71 }
72
73 static void nop_handler(int sig) {
74 }
75
76 _noreturn_ static void crash(int sig) {
77
78         if (!arg_dump_core)
79                 log_error("Caught <%s>, not dumping core.", signal_to_string(sig));
80         else {
81                 struct sigaction sa;
82                 pid_t pid;
83
84                 /* We want to wait for the core process, hence let's enable SIGCHLD */
85                 zero(sa);
86                 sa.sa_handler = nop_handler;
87                 sa.sa_flags = SA_NOCLDSTOP|SA_RESTART;
88                 assert_se(sigaction(SIGCHLD, &sa, NULL) == 0);
89
90                 if ((pid = fork()) < 0)
91                         log_error("Caught <%s>, cannot fork for core dump: %s", signal_to_string(sig), strerror(errno));
92
93                 else if (pid == 0) {
94                         struct rlimit rl;
95
96                         /* Enable default signal handler for core dump */
97                         zero(sa);
98                         sa.sa_handler = SIG_DFL;
99                         assert_se(sigaction(sig, &sa, NULL) == 0);
100
101                         /* Don't limit the core dump size */
102                         zero(rl);
103                         rl.rlim_cur = RLIM_INFINITY;
104                         rl.rlim_max = RLIM_INFINITY;
105                         setrlimit(RLIMIT_CORE, &rl);
106
107                         /* Just to be sure... */
108                         assert_se(chdir("/") == 0);
109
110                         /* Raise the signal again */
111                         raise(sig);
112
113                         assert_not_reached("We shouldn't be here...");
114                         _exit(1);
115
116                 } else {
117                         int status, r;
118
119                         /* Order things nicely. */
120                         if ((r = waitpid(pid, &status, 0)) < 0)
121                                 log_error("Caught <%s>, waitpid() failed: %s", signal_to_string(sig), strerror(errno));
122                         else if (!WCOREDUMP(status))
123                                 log_error("Caught <%s>, core dump failed.", signal_to_string(sig));
124                         else
125                                 log_error("Caught <%s>, dumped core as pid %lu.", signal_to_string(sig), (unsigned long) pid);
126                 }
127         }
128
129         if (arg_crash_chvt)
130                 chvt(arg_crash_chvt);
131
132         if (arg_crash_shell) {
133                 struct sigaction sa;
134                 pid_t pid;
135
136                 log_info("Executing crash shell in 10s...");
137                 sleep(10);
138
139                 /* Let the kernel reap children for us */
140                 zero(sa);
141                 sa.sa_handler = SIG_IGN;
142                 sa.sa_flags = SA_NOCLDSTOP|SA_NOCLDWAIT|SA_RESTART;
143                 assert_se(sigaction(SIGCHLD, &sa, NULL) == 0);
144
145                 if ((pid = fork()) < 0)
146                         log_error("Failed to fork off crash shell: %s", strerror(errno));
147                 else if (pid == 0) {
148                         int fd, r;
149
150                         if ((fd = acquire_terminal("/dev/console", false, true, true)) < 0)
151                                 log_error("Failed to acquire terminal: %s", strerror(-fd));
152                         else if ((r = make_stdio(fd)) < 0)
153                                 log_error("Failed to duplicate terminal fd: %s", strerror(-r));
154
155                         execl("/bin/sh", "/bin/sh", NULL);
156
157                         log_error("execl() failed: %s", strerror(errno));
158                         _exit(1);
159                 }
160
161                 log_info("Successfully spawned crash shall as pid %lu.", (unsigned long) pid);
162         }
163
164         log_info("Freezing execution.");
165         freeze();
166 }
167
168 static void install_crash_handler(void) {
169         struct sigaction sa;
170
171         zero(sa);
172
173         sa.sa_handler = crash;
174         sa.sa_flags = SA_NODEFER;
175
176         sigaction_many(&sa, SIGNALS_CRASH_HANDLER, -1);
177 }
178
179 static int make_null_stdio(void) {
180         int null_fd, r;
181
182         if ((null_fd = open("/dev/null", O_RDWR|O_NOCTTY)) < 0) {
183                 log_error("Failed to open /dev/null: %m");
184                 return -errno;
185         }
186
187         if ((r = make_stdio(null_fd)) < 0)
188                 log_warning("Failed to dup2() device: %s", strerror(-r));
189
190         return r;
191 }
192
193 static int console_setup(bool do_reset) {
194         int tty_fd, r;
195
196         /* If we are init, we connect stdin/stdout/stderr to /dev/null
197          * and make sure we don't have a controlling tty. */
198
199         release_terminal();
200
201         if (!do_reset)
202                 return 0;
203
204         if ((tty_fd = open_terminal("/dev/console", O_WRONLY|O_NOCTTY|O_CLOEXEC)) < 0) {
205                 log_error("Failed to open /dev/console: %s", strerror(-tty_fd));
206                 return -tty_fd;
207         }
208
209         if ((r = reset_terminal(tty_fd)) < 0)
210                 log_error("Failed to reset /dev/console: %s", strerror(-r));
211
212         close_nointr_nofail(tty_fd);
213         return r;
214 }
215
216 static int set_default_unit(const char *u) {
217         char *c;
218
219         assert(u);
220
221         if (!(c = strdup(u)))
222                 return -ENOMEM;
223
224         free(arg_default_unit);
225         arg_default_unit = c;
226         return 0;
227 }
228
229 static int parse_proc_cmdline_word(const char *word) {
230
231         static const char * const rlmap[] = {
232                 "single", SPECIAL_RESCUE_TARGET,
233                 "-s",     SPECIAL_RESCUE_TARGET,
234                 "s",      SPECIAL_RESCUE_TARGET,
235                 "S",      SPECIAL_RESCUE_TARGET,
236                 "1",      SPECIAL_RESCUE_TARGET,
237                 "2",      SPECIAL_RUNLEVEL2_TARGET,
238                 "3",      SPECIAL_RUNLEVEL3_TARGET,
239                 "4",      SPECIAL_RUNLEVEL4_TARGET,
240                 "5",      SPECIAL_RUNLEVEL5_TARGET
241         };
242         bool ignore_quiet = false;
243
244         if (startswith(word, "systemd.unit="))
245                 return set_default_unit(word + 13);
246
247         else if (startswith(word, "systemd.log_target=")) {
248
249                 if (log_set_target_from_string(word + 19) < 0)
250                         log_warning("Failed to parse log target %s. Ignoring.", word + 19);
251
252         } else if (startswith(word, "systemd.log_level=")) {
253
254                 if (log_set_max_level_from_string(word + 18) < 0)
255                         log_warning("Failed to parse log level %s. Ignoring.", word + 18);
256
257         } else if (startswith(word, "systemd.log_color=")) {
258
259                 if (log_show_color_from_string(word + 18) < 0)
260                         log_warning("Failed to parse log color setting %s. Ignoring.", word + 18);
261
262         } else if (startswith(word, "systemd.log_location=")) {
263
264                 if (log_show_location_from_string(word + 21) < 0)
265                         log_warning("Failed to parse log location setting %s. Ignoring.", word + 21);
266
267         } else if (startswith(word, "systemd.dump_core=")) {
268                 int r;
269
270                 if ((r = parse_boolean(word + 18)) < 0)
271                         log_warning("Failed to parse dump core switch %s, Ignoring.", word + 18);
272                 else
273                         arg_dump_core = r;
274
275         } else if (startswith(word, "systemd.crash_shell=")) {
276                 int r;
277
278                 if ((r = parse_boolean(word + 20)) < 0)
279                         log_warning("Failed to parse crash shell switch %s, Ignoring.", word + 20);
280                 else
281                         arg_crash_shell = r;
282
283         } else if (startswith(word, "systemd.confirm_spawn=")) {
284                 int r;
285
286                 if ((r = parse_boolean(word + 22)) < 0)
287                         log_warning("Failed to parse confirm spawn switch %s, Ignoring.", word + 22);
288                 else
289                         arg_confirm_spawn = r;
290
291         } else if (startswith(word, "systemd.crash_chvt=")) {
292                 int k;
293
294                 if (safe_atoi(word + 19, &k) < 0)
295                         log_warning("Failed to parse crash chvt switch %s, Ignoring.", word + 19);
296                 else
297                         arg_crash_chvt = k;
298
299         } else if (startswith(word, "systemd.show_status=")) {
300                 int r;
301
302                 if ((r = parse_boolean(word + 20)) < 0)
303                         log_warning("Failed to parse show status switch %s, Ignoring.", word + 20);
304                 else {
305                         arg_show_status = r;
306                         ignore_quiet = true;
307                 }
308
309         } else if (startswith(word, "systemd.")) {
310
311                 log_warning("Unknown kernel switch %s. Ignoring.", word);
312
313                 log_info("Supported kernel switches:\n"
314                          "systemd.unit=UNIT                        Default unit to start\n"
315                          "systemd.log_target=console|kmsg|syslog|  Log target\n"
316                          "                   syslog-org-kmsg|null\n"
317                          "systemd.log_level=LEVEL                  Log level\n"
318                          "systemd.log_color=0|1                    Highlight important log messages\n"
319                          "systemd.log_location=0|1                 Include code location in log messages\n"
320                          "systemd.dump_core=0|1                    Dump core on crash\n"
321                          "systemd.crash_shell=0|1                  Run shell on crash\n"
322                          "systemd.crash_chvt=N                     Change to VT #N on crash\n"
323                          "systemd.confirm_spawn=0|1                Confirm every process spawn\n"
324                          "systemd.show_status=0|1                  Show status updates on the console during bootup\n");
325
326         } else if (streq(word, "nomodules"))
327                 arg_nomodules = true;
328         else if (streq(word, "quiet")) {
329                 if (!ignore_quiet)
330                         arg_show_status = false;
331         } else {
332                 unsigned i;
333
334                 /* SysV compatibility */
335                 for (i = 0; i < ELEMENTSOF(rlmap); i += 2)
336                         if (streq(word, rlmap[i]))
337                                 return set_default_unit(rlmap[i+1]);
338         }
339
340         return 0;
341 }
342
343 static int config_parse_level(
344                 const char *filename,
345                 unsigned line,
346                 const char *section,
347                 const char *lvalue,
348                 const char *rvalue,
349                 void *data,
350                 void *userdata) {
351
352         assert(filename);
353         assert(lvalue);
354         assert(rvalue);
355
356         log_set_max_level_from_string(rvalue);
357         return 0;
358 }
359
360 static int config_parse_target(
361                 const char *filename,
362                 unsigned line,
363                 const char *section,
364                 const char *lvalue,
365                 const char *rvalue,
366                 void *data,
367                 void *userdata) {
368
369         assert(filename);
370         assert(lvalue);
371         assert(rvalue);
372
373         log_set_target_from_string(rvalue);
374         return 0;
375 }
376
377 static int config_parse_color(
378                 const char *filename,
379                 unsigned line,
380                 const char *section,
381                 const char *lvalue,
382                 const char *rvalue,
383                 void *data,
384                 void *userdata) {
385
386         assert(filename);
387         assert(lvalue);
388         assert(rvalue);
389
390         log_show_color_from_string(rvalue);
391         return 0;
392 }
393
394 static int config_parse_location(
395                 const char *filename,
396                 unsigned line,
397                 const char *section,
398                 const char *lvalue,
399                 const char *rvalue,
400                 void *data,
401                 void *userdata) {
402
403         assert(filename);
404         assert(lvalue);
405         assert(rvalue);
406
407         log_show_location_from_string(rvalue);
408         return 0;
409 }
410
411 static int config_parse_cpu_affinity(
412                 const char *filename,
413                 unsigned line,
414                 const char *section,
415                 const char *lvalue,
416                 const char *rvalue,
417                 void *data,
418                 void *userdata) {
419
420         char *w;
421         size_t l;
422         char *state;
423         cpu_set_t *c = NULL;
424         unsigned ncpus = 0;
425
426         assert(filename);
427         assert(lvalue);
428         assert(rvalue);
429
430         FOREACH_WORD_QUOTED(w, l, rvalue, state) {
431                 char *t;
432                 int r;
433                 unsigned cpu;
434
435                 if (!(t = strndup(w, l)))
436                         return -ENOMEM;
437
438                 r = safe_atou(t, &cpu);
439                 free(t);
440
441                 if (!c)
442                         if (!(c = cpu_set_malloc(&ncpus)))
443                                 return -ENOMEM;
444
445                 if (r < 0 || cpu >= ncpus) {
446                         log_error("[%s:%u] Failed to parse CPU affinity: %s", filename, line, rvalue);
447                         CPU_FREE(c);
448                         return -EBADMSG;
449                 }
450
451                 CPU_SET_S(cpu, CPU_ALLOC_SIZE(ncpus), c);
452         }
453
454         if (c) {
455                 if (sched_setaffinity(0, CPU_ALLOC_SIZE(ncpus), c) < 0)
456                         log_warning("Failed to set CPU affinity: %m");
457
458                 CPU_FREE(c);
459         }
460
461         return 0;
462 }
463
464 static int parse_config_file(void) {
465
466         const ConfigItem items[] = {
467                 { "LogLevel",    config_parse_level,        NULL,             "Manager" },
468                 { "LogTarget",   config_parse_target,       NULL,             "Manager" },
469                 { "LogColor",    config_parse_color,        NULL,             "Manager" },
470                 { "LogLocation", config_parse_location,     NULL,             "Manager" },
471                 { "DumpCore",    config_parse_bool,         &arg_dump_core,   "Manager" },
472                 { "CrashShell",  config_parse_bool,         &arg_crash_shell, "Manager" },
473                 { "ShowStatus",  config_parse_bool,         &arg_show_status, "Manager" },
474                 { "CrashChVT",   config_parse_int,          &arg_crash_chvt,  "Manager" },
475                 { "CPUAffinity", config_parse_cpu_affinity, NULL,             "Manager" },
476                 { NULL, NULL, NULL, NULL }
477         };
478
479         static const char * const sections[] = {
480                 "Manager",
481                 NULL
482         };
483
484         FILE *f;
485         const char *fn;
486         int r;
487
488         fn = arg_running_as == MANAGER_SYSTEM ? SYSTEM_CONFIG_FILE : SESSION_CONFIG_FILE;
489
490         if (!(f = fopen(fn, "re"))) {
491                 if (errno == ENOENT)
492                         return 0;
493
494                 log_warning("Failed to open configuration file '%s': %m", fn);
495                 return 0;
496         }
497
498         if ((r = config_parse(fn, f, sections, items, false, NULL)) < 0)
499                 log_warning("Failed to parse configuration file: %s", strerror(-r));
500
501         fclose(f);
502
503         return 0;
504 }
505
506 static int parse_proc_cmdline(void) {
507         char *line;
508         int r;
509         char *w;
510         size_t l;
511         char *state;
512
513         if ((r = read_one_line_file("/proc/cmdline", &line)) < 0) {
514                 log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(errno));
515                 return 0;
516         }
517
518         FOREACH_WORD_QUOTED(w, l, line, state) {
519                 char *word;
520
521                 if (!(word = strndup(w, l))) {
522                         r = -ENOMEM;
523                         goto finish;
524                 }
525
526                 r = parse_proc_cmdline_word(word);
527                 free(word);
528
529                 if (r < 0)
530                         goto finish;
531         }
532
533         r = 0;
534
535 finish:
536         free(line);
537         return r;
538 }
539
540 static int parse_argv(int argc, char *argv[]) {
541
542         enum {
543                 ARG_LOG_LEVEL = 0x100,
544                 ARG_LOG_TARGET,
545                 ARG_LOG_COLOR,
546                 ARG_LOG_LOCATION,
547                 ARG_UNIT,
548                 ARG_SYSTEM,
549                 ARG_SESSION,
550                 ARG_TEST,
551                 ARG_DUMP_CONFIGURATION_ITEMS,
552                 ARG_DUMP_CORE,
553                 ARG_CRASH_SHELL,
554                 ARG_CONFIRM_SPAWN,
555                 ARG_SHOW_STATUS,
556                 ARG_DESERIALIZE,
557                 ARG_INTROSPECT
558         };
559
560         static const struct option options[] = {
561                 { "log-level",                required_argument, NULL, ARG_LOG_LEVEL                },
562                 { "log-target",               required_argument, NULL, ARG_LOG_TARGET               },
563                 { "log-color",                optional_argument, NULL, ARG_LOG_COLOR                },
564                 { "log-location",             optional_argument, NULL, ARG_LOG_LOCATION             },
565                 { "unit",                     required_argument, NULL, ARG_UNIT                     },
566                 { "system",                   no_argument,       NULL, ARG_SYSTEM                   },
567                 { "session",                  no_argument,       NULL, ARG_SESSION                  },
568                 { "test",                     no_argument,       NULL, ARG_TEST                     },
569                 { "help",                     no_argument,       NULL, 'h'                          },
570                 { "dump-configuration-items", no_argument,       NULL, ARG_DUMP_CONFIGURATION_ITEMS },
571                 { "dump-core",                no_argument,       NULL, ARG_DUMP_CORE                },
572                 { "crash-shell",              no_argument,       NULL, ARG_CRASH_SHELL              },
573                 { "confirm-spawn",            no_argument,       NULL, ARG_CONFIRM_SPAWN            },
574                 { "show-status",              no_argument,       NULL, ARG_SHOW_STATUS              },
575                 { "deserialize",              required_argument, NULL, ARG_DESERIALIZE              },
576                 { "introspect",               optional_argument, NULL, ARG_INTROSPECT               },
577                 { NULL,                       0,                 NULL, 0                            }
578         };
579
580         int c, r;
581
582         assert(argc >= 1);
583         assert(argv);
584
585         while ((c = getopt_long(argc, argv, "hD", options, NULL)) >= 0)
586
587                 switch (c) {
588
589                 case ARG_LOG_LEVEL:
590                         if ((r = log_set_max_level_from_string(optarg)) < 0) {
591                                 log_error("Failed to parse log level %s.", optarg);
592                                 return r;
593                         }
594
595                         break;
596
597                 case ARG_LOG_TARGET:
598
599                         if ((r = log_set_target_from_string(optarg)) < 0) {
600                                 log_error("Failed to parse log target %s.", optarg);
601                                 return r;
602                         }
603
604                         break;
605
606                 case ARG_LOG_COLOR:
607
608                         if (optarg) {
609                                 if ((r = log_show_color_from_string(optarg)) < 0) {
610                                         log_error("Failed to parse log color setting %s.", optarg);
611                                         return r;
612                                 }
613                         } else
614                                 log_show_color(true);
615
616                         break;
617
618                 case ARG_LOG_LOCATION:
619
620                         if (optarg) {
621                                 if ((r = log_show_location_from_string(optarg)) < 0) {
622                                         log_error("Failed to parse log location setting %s.", optarg);
623                                         return r;
624                                 }
625                         } else
626                                 log_show_location(true);
627
628                         break;
629
630                 case ARG_UNIT:
631
632                         if ((r = set_default_unit(optarg)) < 0) {
633                                 log_error("Failed to set default unit %s: %s", optarg, strerror(-r));
634                                 return r;
635                         }
636
637                         break;
638
639                 case ARG_SYSTEM:
640                         arg_running_as = MANAGER_SYSTEM;
641                         break;
642
643                 case ARG_SESSION:
644                         arg_running_as = MANAGER_SESSION;
645                         break;
646
647                 case ARG_TEST:
648                         arg_action = ACTION_TEST;
649                         break;
650
651                 case ARG_DUMP_CONFIGURATION_ITEMS:
652                         arg_action = ACTION_DUMP_CONFIGURATION_ITEMS;
653                         break;
654
655                 case ARG_DUMP_CORE:
656                         arg_dump_core = true;
657                         break;
658
659                 case ARG_CRASH_SHELL:
660                         arg_crash_shell = true;
661                         break;
662
663                 case ARG_CONFIRM_SPAWN:
664                         arg_confirm_spawn = true;
665                         break;
666
667                 case ARG_SHOW_STATUS:
668                         arg_show_status = true;
669                         break;
670
671                 case ARG_DESERIALIZE: {
672                         int fd;
673                         FILE *f;
674
675                         if ((r = safe_atoi(optarg, &fd)) < 0 || fd < 0) {
676                                 log_error("Failed to parse deserialize option %s.", optarg);
677                                 return r;
678                         }
679
680                         if (!(f = fdopen(fd, "r"))) {
681                                 log_error("Failed to open serialization fd: %m");
682                                 return r;
683                         }
684
685                         if (serialization)
686                                 fclose(serialization);
687
688                         serialization = f;
689
690                         break;
691                 }
692
693                 case ARG_INTROSPECT: {
694                         const char * const * i = NULL;
695
696                         for (i = bus_interface_table; *i; i += 2)
697                                 if (!optarg || streq(i[0], optarg)) {
698                                         fputs(DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE
699                                               "<node>\n", stdout);
700                                         fputs(i[1], stdout);
701                                         fputs("</node>\n", stdout);
702
703                                         if (optarg)
704                                                 break;
705                                 }
706
707                         if (!i[0] && optarg)
708                                 log_error("Unknown interface %s.", optarg);
709
710                         arg_action = ACTION_DONE;
711                         break;
712                 }
713
714                 case 'h':
715                         arg_action = ACTION_HELP;
716                         break;
717
718                 case 'D':
719                         log_set_max_level(LOG_DEBUG);
720                         break;
721
722                 case '?':
723                         return -EINVAL;
724
725                 default:
726                         log_error("Unknown option code %c", c);
727                         return -EINVAL;
728                 }
729
730         /* PID 1 will get the kernel arguments as parameters, which we
731          * ignore and unconditionally read from
732          * /proc/cmdline. However, we need to ignore those arguments
733          * here. */
734         if (arg_running_as != MANAGER_SYSTEM && optind < argc) {
735                 log_error("Excess arguments.");
736                 return -EINVAL;
737         }
738
739         return 0;
740 }
741
742 static int help(void) {
743
744         printf("%s [OPTIONS...]\n\n"
745                "Starts up and maintains the system or a session.\n\n"
746                "  -h --help                      Show this help\n"
747                "     --test                      Determine startup sequence, dump it and exit\n"
748                "     --dump-configuration-items  Dump understood unit configuration items\n"
749                "     --introspect[=INTERFACE]    Extract D-Bus interface data\n"
750                "     --unit=UNIT                 Set default unit\n"
751                "     --system                    Run a system instance, even if PID != 1\n"
752                "     --session                   Run a session instance\n"
753                "     --dump-core                 Dump core on crash\n"
754                "     --crash-shell               Run shell on crash\n"
755                "     --confirm-spawn             Ask for confirmation when spawning processes\n"
756                "     --show-status               Show status updates on the console during bootup\n"
757                "     --log-target=TARGET         Set log target (console, syslog, kmsg, syslog-or-kmsg, null)\n"
758                "     --log-level=LEVEL           Set log level (debug, info, notice, warning, err, crit, alert, emerg)\n"
759                "     --log-color[=0|1]           Highlight important log messages\n"
760                "     --log-location[=0|1]        Include code location in log messages\n",
761                program_invocation_short_name);
762
763         return 0;
764 }
765
766 static int prepare_reexecute(Manager *m, FILE **_f, FDSet **_fds) {
767         FILE *f = NULL;
768         FDSet *fds = NULL;
769         int r;
770
771         assert(m);
772         assert(_f);
773         assert(_fds);
774
775         if ((r = manager_open_serialization(&f)) < 0) {
776                 log_error("Failed to create serialization faile: %s", strerror(-r));
777                 goto fail;
778         }
779
780         if (!(fds = fdset_new())) {
781                 r = -ENOMEM;
782                 log_error("Failed to allocate fd set: %s", strerror(-r));
783                 goto fail;
784         }
785
786         if ((r = manager_serialize(m, f, fds)) < 0) {
787                 log_error("Failed to serialize state: %s", strerror(-r));
788                 goto fail;
789         }
790
791         if (fseeko(f, 0, SEEK_SET) < 0) {
792                 log_error("Failed to rewind serialization fd: %m");
793                 goto fail;
794         }
795
796         if ((r = fd_cloexec(fileno(f), false)) < 0) {
797                 log_error("Failed to disable O_CLOEXEC for serialization: %s", strerror(-r));
798                 goto fail;
799         }
800
801         if ((r = fdset_cloexec(fds, false)) < 0) {
802                 log_error("Failed to disable O_CLOEXEC for serialization fds: %s", strerror(-r));
803                 goto fail;
804         }
805
806         *_f = f;
807         *_fds = fds;
808
809         return 0;
810
811 fail:
812         fdset_free(fds);
813
814         if (f)
815                 fclose(f);
816
817         return r;
818 }
819
820 int main(int argc, char *argv[]) {
821         Manager *m = NULL;
822         Unit *target = NULL;
823         Job *job = NULL;
824         int r, retval = 1;
825         FDSet *fds = NULL;
826         bool reexecute = false;
827
828         if (getpid() != 1 && strstr(program_invocation_short_name, "init")) {
829                 /* This is compatbility support for SysV, where
830                  * calling init as a user is identical to telinit. */
831
832                 errno = -ENOENT;
833                 execv(SYSTEMCTL_BINARY_PATH, argv);
834                 log_error("Failed to exec " SYSTEMCTL_BINARY_PATH ": %m");
835                 return 1;
836         }
837
838         log_show_color(true);
839         log_show_location(false);
840         log_set_max_level(LOG_INFO);
841
842         if (getpid() == 1) {
843                 arg_running_as = MANAGER_SYSTEM;
844                 log_set_target(LOG_TARGET_SYSLOG_OR_KMSG);
845         } else {
846                 arg_running_as = MANAGER_SESSION;
847                 log_set_target(LOG_TARGET_CONSOLE);
848         }
849
850         if (set_default_unit(SPECIAL_DEFAULT_TARGET) < 0)
851                 goto finish;
852
853         /* Mount /proc, /sys and friends, so that /proc/cmdline and
854          * /proc/$PID/fd is available. */
855         if (geteuid() == 0 && !getenv("SYSTEMD_SKIP_API_MOUNTS"))
856                 if (mount_setup() < 0)
857                         goto finish;
858
859         /* Reset all signal handlers. */
860         assert_se(reset_all_signal_handlers() == 0);
861
862         /* If we are init, we can block sigkill. Yay. */
863         ignore_signals(SIGNALS_IGNORE, -1);
864
865         if (parse_config_file() < 0)
866                 goto finish;
867
868         if (arg_running_as == MANAGER_SYSTEM)
869                 if (parse_proc_cmdline() < 0)
870                         goto finish;
871
872         log_parse_environment();
873
874         if (parse_argv(argc, argv) < 0)
875                 goto finish;
876
877         if (arg_action == ACTION_HELP) {
878                 retval = help();
879                 goto finish;
880         } else if (arg_action == ACTION_DUMP_CONFIGURATION_ITEMS) {
881                 unit_dump_config_items(stdout);
882                 retval = 0;
883                 goto finish;
884         } else if (arg_action == ACTION_DONE) {
885                 retval = 0;
886                 goto finish;
887         }
888
889         assert_se(arg_action == ACTION_RUN || arg_action == ACTION_TEST);
890
891         /* Remember open file descriptors for later deserialization */
892         if (serialization) {
893                 if ((r = fdset_new_fill(&fds)) < 0) {
894                         log_error("Failed to allocate fd set: %s", strerror(-r));
895                         goto finish;
896                 }
897
898                 assert_se(fdset_remove(fds, fileno(serialization)) >= 0);
899         } else
900                 close_all_fds(NULL, 0);
901
902         /* Set up PATH unless it is already set */
903         setenv("PATH",
904                "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
905                arg_running_as == MANAGER_SYSTEM);
906
907         /* Move out of the way, so that we won't block unmounts */
908         assert_se(chdir("/")  == 0);
909
910         if (arg_running_as == MANAGER_SYSTEM) {
911                 /* Become a session leader if we aren't one yet. */
912                 setsid();
913
914                 /* Disable the umask logic */
915                 umask(0);
916         }
917
918         /* Make sure D-Bus doesn't fiddle with the SIGPIPE handlers */
919         dbus_connection_set_change_sigpipe(FALSE);
920
921         /* Reset the console, but only if this is really init and we
922          * are freshly booted */
923         if (arg_running_as == MANAGER_SYSTEM && arg_action == ACTION_RUN) {
924                 console_setup(getpid() == 1 && !serialization);
925                 make_null_stdio();
926         }
927
928         /* Open the logging devices, if possible and necessary */
929         log_open();
930
931         /* Make sure we leave a core dump without panicing the
932          * kernel. */
933         if (getpid() == 1)
934                 install_crash_handler();
935
936         log_info(PACKAGE_STRING " running in %s mode.", manager_running_as_to_string(arg_running_as));
937
938         if (arg_running_as == MANAGER_SYSTEM && !serialization) {
939                 if (arg_show_status)
940                         status_welcome();
941                 modprobe_setup(arg_nomodules);
942                 kmod_setup();
943                 hostname_setup();
944                 loopback_setup();
945         }
946
947         if ((r = manager_new(arg_running_as, &m)) < 0) {
948                 log_error("Failed to allocate manager object: %s", strerror(-r));
949                 goto finish;
950         }
951
952         m->confirm_spawn = arg_confirm_spawn;
953         m->show_status = arg_show_status;
954
955         if ((r = manager_startup(m, serialization, fds)) < 0)
956                 log_error("Failed to fully start up daemon: %s", strerror(-r));
957
958         if (fds) {
959                 /* This will close all file descriptors that were opened, but
960                  * not claimed by any unit. */
961
962                 fdset_free(fds);
963                 fds = NULL;
964         }
965
966         if (serialization) {
967                 fclose(serialization);
968                 serialization = NULL;
969         } else {
970                 DBusError error;
971
972                 dbus_error_init(&error);
973
974                 log_debug("Activating default unit: %s", arg_default_unit);
975
976                 if ((r = manager_load_unit(m, arg_default_unit, NULL, &error, &target)) < 0) {
977                         log_error("Failed to load default target: %s", bus_error(&error, r));
978                         dbus_error_free(&error);
979
980                         log_info("Trying to load rescue target...");
981                         if ((r = manager_load_unit(m, SPECIAL_RESCUE_TARGET, NULL, &error, &target)) < 0) {
982                                 log_error("Failed to load rescue target: %s", bus_error(&error, r));
983                                 dbus_error_free(&error);
984                                 goto finish;
985                         }
986                 }
987
988                 if (arg_action == ACTION_TEST) {
989                         printf("-> By units:\n");
990                         manager_dump_units(m, stdout, "\t");
991                 }
992
993                 if ((r = manager_add_job(m, JOB_START, target, JOB_REPLACE, false, &error, &job)) < 0) {
994                         log_error("Failed to start default target: %s", bus_error(&error, r));
995                         dbus_error_free(&error);
996                         goto finish;
997                 }
998
999                 if (arg_action == ACTION_TEST) {
1000                         printf("-> By jobs:\n");
1001                         manager_dump_jobs(m, stdout, "\t");
1002                         retval = 0;
1003                         goto finish;
1004                 }
1005         }
1006
1007         for (;;) {
1008                 if ((r = manager_loop(m)) < 0) {
1009                         log_error("Failed to run mainloop: %s", strerror(-r));
1010                         goto finish;
1011                 }
1012
1013                 switch (m->exit_code) {
1014
1015                 case MANAGER_EXIT:
1016                         retval = 0;
1017                         log_debug("Exit.");
1018                         goto finish;
1019
1020                 case MANAGER_RELOAD:
1021                         log_info("Reloading.");
1022                         if ((r = manager_reload(m)) < 0)
1023                                 log_error("Failed to reload: %s", strerror(-r));
1024                         break;
1025
1026                 case MANAGER_REEXECUTE:
1027                         if (prepare_reexecute(m, &serialization, &fds) < 0)
1028                                 goto finish;
1029
1030                         reexecute = true;
1031                         log_notice("Reexecuting.");
1032                         goto finish;
1033
1034                 default:
1035                         assert_not_reached("Unknown exit code.");
1036                 }
1037         }
1038
1039 finish:
1040         if (m)
1041                 manager_free(m);
1042
1043         free(arg_default_unit);
1044
1045         dbus_shutdown();
1046
1047         if (reexecute) {
1048                 const char *args[14];
1049                 unsigned i = 0;
1050                 char sfd[16];
1051
1052                 assert(serialization);
1053                 assert(fds);
1054
1055                 args[i++] = SYSTEMD_BINARY_PATH;
1056
1057                 args[i++] = "--log-level";
1058                 args[i++] = log_level_to_string(log_get_max_level());
1059
1060                 args[i++] = "--log-target";
1061                 args[i++] = log_target_to_string(log_get_target());
1062
1063                 if (arg_running_as == MANAGER_SYSTEM)
1064                         args[i++] = "--system";
1065                 else
1066                         args[i++] = "--session";
1067
1068                 if (arg_dump_core)
1069                         args[i++] = "--dump-core";
1070
1071                 if (arg_crash_shell)
1072                         args[i++] = "--crash-shell";
1073
1074                 if (arg_confirm_spawn)
1075                         args[i++] = "--confirm-spawn";
1076
1077                 if (arg_show_status)
1078                         args[i++] = "--show-status";
1079
1080                 snprintf(sfd, sizeof(sfd), "%i", fileno(serialization));
1081                 char_array_0(sfd);
1082
1083                 args[i++] = "--deserialize";
1084                 args[i++] = sfd;
1085
1086                 args[i++] = NULL;
1087
1088                 assert(i <= ELEMENTSOF(args));
1089
1090                 execv(args[0], (char* const*) args);
1091
1092                 log_error("Failed to reexecute: %m");
1093         }
1094
1095         if (serialization)
1096                 fclose(serialization);
1097
1098         if (fds)
1099                 fdset_free(fds);
1100
1101         if (getpid() == 1)
1102                 freeze();
1103
1104         return retval;
1105 }