31750482181e52f0c5151046bb94741343c465a4
[project/procd.git] / inittab.c
1 /*
2 * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
3 * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU Lesser General Public License version 2.1
7 * as published by the Free Software Foundation
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 */
14
15 #define _GNU_SOURCE
16 #include <sys/types.h>
17 #include <sys/stat.h>
18 #include <sys/ioctl.h>
19
20 #include <fcntl.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <unistd.h>
24 #include <regex.h>
25 #include <ctype.h>
26
27 #include <libubox/utils.h>
28 #include <libubox/list.h>
29
30 #include "utils/utils.h"
31 #include "procd.h"
32 #include "rcS.h"
33
34 #ifndef O_PATH
35 #define O_PATH 010000000
36 #endif
37
38 #define TAG_ID 0
39 #define TAG_RUNLVL 1
40 #define TAG_ACTION 2
41 #define TAG_PROCESS 3
42
43 #define MAX_ARGS 8
44
45 struct init_action;
46 char *console = NULL;
47
48 struct init_handler {
49 const char *name;
50 void (*cb) (struct init_action *a);
51 int multi;
52 };
53
54 struct init_action {
55 struct list_head list;
56
57 char *id;
58 char *argv[MAX_ARGS];
59 char *line;
60
61 struct init_handler *handler;
62 struct uloop_process proc;
63
64 int respawn;
65 struct uloop_timeout tout;
66 };
67
68 static const char *tab = "/etc/inittab";
69 static char *ask = "/sbin/askfirst";
70
71 static LIST_HEAD(actions);
72
73 static int dev_exist(const char *dev)
74 {
75 int dfd, fd;
76
77 dfd = open("/dev", O_PATH|O_DIRECTORY);
78
79 if (dfd < 0)
80 return 0;
81
82 fd = openat(dfd, dev, O_RDONLY);
83 close(dfd);
84
85 if (fd < 0)
86 return 0;
87
88 close(fd);
89 return 1;
90 }
91
92 static void fork_worker(struct init_action *a)
93 {
94 pid_t p;
95
96 a->proc.pid = fork();
97 if (!a->proc.pid) {
98 p = setsid();
99
100 if (patch_stdio(a->id))
101 ERROR("Failed to setup i/o redirection\n");
102
103 ioctl(STDIN_FILENO, TIOCSCTTY, 1);
104 tcsetpgrp(STDIN_FILENO, p);
105
106 execvp(a->argv[0], a->argv);
107 ERROR("Failed to execute %s: %m\n", a->argv[0]);
108 exit(-1);
109 }
110
111 if (a->proc.pid > 0) {
112 DEBUG(4, "Launched new %s action, pid=%d\n",
113 a->handler->name,
114 (int) a->proc.pid);
115 uloop_process_add(&a->proc);
116 }
117 }
118
119 static void child_exit(struct uloop_process *proc, int ret)
120 {
121 struct init_action *a = container_of(proc, struct init_action, proc);
122
123 DEBUG(4, "pid:%d, exitcode:%d\n", proc->pid, ret);
124 proc->pid = 0;
125
126 uloop_timeout_set(&a->tout, a->respawn);
127 }
128
129 static void respawn(struct uloop_timeout *tout)
130 {
131 struct init_action *a = container_of(tout, struct init_action, tout);
132 if (!a->proc.pid)
133 fork_worker(a);
134 }
135
136 static void rcdone(struct runqueue *q)
137 {
138 procd_state_next();
139 }
140
141 static void runrc(struct init_action *a)
142 {
143 if (!a->argv[1] || !a->argv[2]) {
144 ERROR("valid format is rcS <S|K> <param>\n");
145 return;
146 }
147
148 /* proceed even if no init or shutdown scripts run */
149 if (rcS(a->argv[1], a->argv[2], rcdone))
150 rcdone(NULL);
151 }
152
153 static void askfirst(struct init_action *a)
154 {
155 int i;
156
157 if (!dev_exist(a->id) || (console && !strcmp(console, a->id))) {
158 DEBUG(4, "Skipping %s\n", a->id);
159 return;
160 }
161
162 a->tout.cb = respawn;
163 for (i = MAX_ARGS - 1; i >= 1; i--)
164 a->argv[i] = a->argv[i - 1];
165 a->argv[0] = ask;
166 a->respawn = 500;
167
168 a->proc.cb = child_exit;
169 if (!a->proc.pid)
170 fork_worker(a);
171 }
172
173 static void askconsole(struct init_action *a)
174 {
175 char line[256], *tty, *split;
176 int i;
177
178 tty = get_cmdline_val("console", line, sizeof(line));
179 if (tty != NULL) {
180 split = strchr(tty, ',');
181 if (split != NULL)
182 *split = '\0';
183
184 if (!dev_exist(tty)) {
185 DEBUG(4, "skipping %s\n", tty);
186 return;
187 }
188
189 console = strdup(tty);
190 a->id = strdup(tty);
191 }
192 else {
193 console = NULL;
194 a->id = NULL;
195 }
196
197 a->tout.cb = respawn;
198 for (i = MAX_ARGS - 1; i >= 1; i--)
199 a->argv[i] = a->argv[i - 1];
200 a->argv[0] = ask;
201 a->respawn = 500;
202
203 a->proc.cb = child_exit;
204 if (!a->proc.pid)
205 fork_worker(a);
206 }
207
208 static void rcrespawn(struct init_action *a)
209 {
210 a->tout.cb = respawn;
211 a->respawn = 500;
212
213 a->proc.cb = child_exit;
214 if (!a->proc.pid)
215 fork_worker(a);
216 }
217
218 static struct init_handler handlers[] = {
219 {
220 .name = "sysinit",
221 .cb = runrc,
222 }, {
223 .name = "shutdown",
224 .cb = runrc,
225 }, {
226 .name = "askfirst",
227 .cb = askfirst,
228 .multi = 1,
229 }, {
230 .name = "askconsole",
231 .cb = askconsole,
232 .multi = 1,
233 }, {
234 .name = "respawn",
235 .cb = rcrespawn,
236 .multi = 1,
237 }, {
238 .name = "askconsolelate",
239 .cb = askconsole,
240 .multi = 1,
241 }, {
242 .name = "respawnlate",
243 .cb = rcrespawn,
244 .multi = 1,
245 }
246 };
247
248 static int add_action(struct init_action *a, const char *name)
249 {
250 int i;
251
252 for (i = 0; i < ARRAY_SIZE(handlers); i++)
253 if (!strcmp(handlers[i].name, name)) {
254 a->handler = &handlers[i];
255 list_add_tail(&a->list, &actions);
256 return 0;
257 }
258 ERROR("Unknown init handler %s\n", name);
259 return -1;
260 }
261
262 void procd_inittab_run(const char *handler)
263 {
264 struct init_action *a;
265
266 list_for_each_entry(a, &actions, list)
267 if (!strcmp(a->handler->name, handler)) {
268 if (a->handler->multi) {
269 a->handler->cb(a);
270 continue;
271 }
272 a->handler->cb(a);
273 break;
274 }
275 }
276
277 void procd_inittab(void)
278 {
279 #define LINE_LEN 128
280 FILE *fp = fopen(tab, "r");
281 struct init_action *a;
282 regex_t pat_inittab;
283 regmatch_t matches[5];
284 char *line;
285
286 if (!fp) {
287 ERROR("Failed to open %s: %m\n", tab);
288 return;
289 }
290
291 regcomp(&pat_inittab, "([a-zA-Z0-9]*):([a-zA-Z0-9]*):([a-zA-Z0-9]*):(.*)", REG_EXTENDED);
292 line = malloc(LINE_LEN);
293 a = calloc(1, sizeof(struct init_action));
294
295 while (fgets(line, LINE_LEN, fp)) {
296 char *tags[TAG_PROCESS + 1];
297 char *tok;
298 int i;
299 int len = strlen(line);
300
301 while (isspace(line[len - 1]))
302 len--;
303 line[len] = 0;
304
305 if (*line == '#')
306 continue;
307
308 if (regexec(&pat_inittab, line, 5, matches, 0))
309 continue;
310
311 DEBUG(4, "Parsing inittab - %s\n", line);
312
313 for (i = TAG_ID; i <= TAG_PROCESS; i++) {
314 line[matches[i].rm_eo] = '\0';
315 tags[i] = &line[matches[i + 1].rm_so];
316 };
317
318 tok = strtok(tags[TAG_PROCESS], " ");
319 for (i = 0; i < (MAX_ARGS - 1) && tok; i++) {
320 a->argv[i] = tok;
321 tok = strtok(NULL, " ");
322 }
323 a->argv[i] = NULL;
324 a->id = tags[TAG_ID];
325 a->line = line;
326
327 if (add_action(a, tags[TAG_ACTION]))
328 continue;
329 line = malloc(LINE_LEN);
330 a = calloc(1, sizeof(struct init_action));
331 }
332
333 fclose(fp);
334 free(line);
335 free(a);
336 regfree(&pat_inittab);
337 }