Drop hurd specific dependency on libc0.3 (>= 2.3.2.ds1-12). It is
[sysvinit.git] / contrib / start-stop-daemon.c
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.
7 */
8
9 #include <stdio.h>
10 #include <stdlib.h>
11 #include <string.h>
12 #include <stdarg.h>
13 #include <signal.h>
14 #include <errno.h>
15 #include <sys/stat.h>
16 #include <dirent.h>
17 #include <unistd.h>
18 #include <getopt.h>
19 #include <pwd.h>
20
21 #define VERSION "version 0.3, 1996-06-05"
22
23 static int testmode = 0;
24 static int quietmode = 0;
25 static int exitnodo = 1;
26 static int start = 0;
27 static int stop = 0;
28 static int signal_nr = 15;
29 static int user_id = -1;
30 static const char *userspec = NULL;
31 static const char *cmdname = NULL;
32 static char *execname = NULL;
33 static char *startas = NULL;
34 static const char *pidfile = NULL;
35 static const char *progname = "";
36
37 static struct stat exec_stat;
38
39 struct pid_list {
40 struct pid_list *next;
41 int pid;
42 };
43
44 static struct pid_list *found = NULL;
45 static struct pid_list *killed = NULL;
46
47 static void *xmalloc(int size);
48 static void push(struct pid_list **list, int pid);
49 static void do_help(void);
50 static void parse_options(int argc, char * const *argv);
51 static int pid_is_exec(int pid, const struct stat *esb);
52 static int pid_is_user(int pid, int uid);
53 static int pid_is_cmd(int pid, const char *name);
54 static void check(int pid);
55 static void do_pidfile(const char *name);
56 static void do_procfs(void);
57 static void do_stop(void);
58
59 #ifdef __GNUC__
60 static void fatal(const char *format, ...)
61 __attribute__((noreturn, format(printf, 1, 2)));
62 static void badusage(const char *msg)
63 __attribute__((noreturn));
64 #else
65 static void fatal(const char *format, ...);
66 static void badusage(const char *msg);
67 #endif
68
69 static void
70 fatal(const char *format, ...)
71 {
72 va_list arglist;
73
74 fprintf(stderr, "%s: ", progname);
75 va_start(arglist, format);
76 vfprintf(stderr, format, arglist);
77 va_end(arglist);
78 putc('\n', stderr);
79 exit(2);
80 }
81
82
83 static void *
84 xmalloc(int size)
85 {
86 void *ptr;
87
88 ptr = malloc(size);
89 if (ptr)
90 return ptr;
91 fatal("malloc(%d) failed", size);
92 }
93
94
95 static void
96 push(struct pid_list **list, int pid)
97 {
98 struct pid_list *p;
99
100 p = xmalloc(sizeof(*p));
101 p->next = *list;
102 p->pid = pid;
103 *list = p;
104 }
105
106
107 static void
108 do_help(void)
109 {
110 printf("\
111 start-stop-daemon for Debian Linux - small and fast C version written by\n\
112 Marek Michalkiewicz <marekm@i17linuxb.ists.pwr.wroc.pl>, public domain.\n"
113 VERSION "\n\
114 \n\
115 Usage:
116 start-stop-daemon -S|--start options ... -- arguments ...\n\
117 start-stop-daemon -K|--stop options ...\n\
118 start-stop-daemon -H|--help\n\
119 start-stop-daemon -V|--version\n\
120 \n\
121 Options (at least one of --exec|--pidfile|--user is required):
122 -x|--exec <executable> program to start/check if it is running\n\
123 -p|--pidfile <pid-file> pid file to check\n\
124 -u|--user <username>|<uid> stop this user's processes\n\
125 -n|--name <process-name> stop processes with this name\n\
126 -s|--signal <signal> signal to send (default 15)\n\
127 -a|--startas <pathname> program to start (default <executable>)\n\
128 -t|--test test mode, don't do anything\n\
129 -o|--oknodo exit status 0 (not 1) if nothing done\n\
130 -q|--quiet | -v, --verbose\n\
131 \n\
132 Exit status: 0 = done 1 = nothing done (=> 0 if --oknodo) 2 = trouble\n");
133 }
134
135
136 static void
137 badusage(const char *msg)
138 {
139 if (msg && *msg)
140 fprintf(stderr, "%s: %s\n", progname, msg);
141 fprintf(stderr, "Try `%s --help' for more information.\n", progname);
142 exit(2);
143 }
144
145
146 static void
147 parse_options(int argc, char * const *argv)
148 {
149 static struct option longopts[] = {
150 { "help", 0, NULL, 'H'},
151 { "stop", 0, NULL, 'K'},
152 { "start", 0, NULL, 'S'},
153 { "version", 0, NULL, 'V'},
154 { "startas", 1, NULL, 'a'},
155 { "name", 1, NULL, 'n'},
156 { "oknodo", 0, NULL, 'o'},
157 { "pidfile", 1, NULL, 'p'},
158 { "quiet", 0, NULL, 'q'},
159 { "signal", 1, NULL, 's'},
160 { "test", 0, NULL, 't'},
161 { "user", 1, NULL, 'u'},
162 { "verbose", 0, NULL, 'v'},
163 { "exec", 1, NULL, 'x'},
164 { NULL, 0, NULL, 0}
165 };
166 int c;
167
168 for (;;) {
169 c = getopt_long(argc, argv, "HKSVa:n:op:qs:tu:vx:",
170 longopts, (int *) 0);
171 if (c == -1)
172 break;
173 switch (c) {
174 case 'H': /* --help */
175 do_help();
176 exit(0);
177 case 'K': /* --stop */
178 stop = 1;
179 break;
180 case 'S': /* --start */
181 start = 1;
182 break;
183 case 'V': /* --version */
184 printf("start-stop-daemon " VERSION "\n");
185 exit(0);
186 case 'a': /* --startas <pathname> */
187 startas = optarg;
188 break;
189 case 'n': /* --name <process-name> */
190 cmdname = optarg;
191 break;
192 case 'o': /* --oknodo */
193 exitnodo = 0;
194 break;
195 case 'p': /* --pidfile <pid-file> */
196 pidfile = optarg;
197 break;
198 case 'q': /* --quiet */
199 quietmode = 1;
200 break;
201 case 's': /* --signal <signal> */
202 if (sscanf(optarg, "%d", &signal_nr) != 1)
203 badusage("--signal takes a numeric argument");
204 break;
205 case 't': /* --test */
206 testmode = 1;
207 break;
208 case 'u': /* --user <username>|<uid> */
209 userspec = optarg;
210 break;
211 case 'v': /* --verbose */
212 quietmode = -1;
213 break;
214 case 'x': /* --exec <executable> */
215 execname = optarg;
216 break;
217 default:
218 badusage(""); /* message printed by getopt */
219 }
220 }
221
222 if (start == stop)
223 badusage("need one of --start or --stop");
224
225 if (!execname && !pidfile && !userspec)
226 badusage("need at least one of --exec, --pidfile or --user");
227
228 if (!startas)
229 startas = execname;
230
231 if (start && !startas)
232 badusage("--start needs --exec or --startas");
233 }
234
235
236 static int
237 pid_is_exec(int pid, const struct stat *esb)
238 {
239 struct stat sb;
240 char buf[32];
241
242 sprintf(buf, "/proc/%d/exe", pid);
243 if (stat(buf, &sb) != 0)
244 return 0;
245 return (sb.st_dev == esb->st_dev && sb.st_ino == esb->st_ino);
246 }
247
248
249 static int
250 pid_is_user(int pid, int uid)
251 {
252 struct stat sb;
253 char buf[32];
254
255 sprintf(buf, "/proc/%d", pid);
256 if (stat(buf, &sb) != 0)
257 return 0;
258 return (sb.st_uid == uid);
259 }
260
261
262 static int
263 pid_is_cmd(int pid, const char *name)
264 {
265 char buf[32];
266 FILE *f;
267 int c;
268
269 sprintf(buf, "/proc/%d/stat", pid);
270 f = fopen(buf, "r");
271 if (!f)
272 return 0;
273 while ((c = getc(f)) != EOF && c != '(')
274 ;
275 if (c != '(') {
276 fclose(f);
277 return 0;
278 }
279 /* this hopefully handles command names containing ')' */
280 while ((c = getc(f)) != EOF && c == *name)
281 name++;
282 fclose(f);
283 return (c == ')' && *name == '\0');
284 }
285
286
287 static void
288 check(int pid)
289 {
290 if (execname && !pid_is_exec(pid, &exec_stat))
291 return;
292 if (userspec && !pid_is_user(pid, user_id))
293 return;
294 if (cmdname && !pid_is_cmd(pid, cmdname))
295 return;
296 push(&found, pid);
297 }
298
299
300 static void
301 do_pidfile(const char *name)
302 {
303 FILE *f;
304 int pid;
305
306 f = fopen(name, "r");
307 if (f) {
308 if (fscanf(f, "%d", &pid) == 1)
309 check(pid);
310 fclose(f);
311 }
312 }
313
314
315 static void
316 do_procfs(void)
317 {
318 DIR *procdir;
319 struct dirent *entry;
320 int foundany, pid;
321
322 procdir = opendir("/proc");
323 if (!procdir)
324 fatal("opendir /proc: %s", strerror(errno));
325
326 foundany = 0;
327 while ((entry = readdir(procdir)) != NULL) {
328 if (sscanf(entry->d_name, "%d", &pid) != 1)
329 continue;
330 foundany++;
331 check(pid);
332 }
333 closedir(procdir);
334 if (!foundany)
335 fatal("nothing in /proc - not mounted?");
336 }
337
338
339 static void
340 do_stop(void)
341 {
342 char what[1024];
343 struct pid_list *p;
344
345 if (cmdname)
346 strcpy(what, cmdname);
347 else if (execname)
348 strcpy(what, execname);
349 else if (pidfile)
350 sprintf(what, "process in pidfile `%s'", pidfile);
351 else if (userspec)
352 sprintf(what, "process(es) owned by `%s'", userspec);
353 else
354 fatal("internal error, please report");
355
356 if (!found) {
357 if (quietmode <= 0)
358 printf("no %s found; none killed.\n", what);
359 exit(exitnodo);
360 }
361 for (p = found; p; p = p->next) {
362 if (testmode)
363 printf("would send signal %d to %d.\n",
364 signal_nr, p->pid);
365 else if (kill(p->pid, signal_nr) == 0)
366 push(&killed, p->pid);
367 else
368 printf("%s: warning: failed to kill %d: %s\n",
369 progname, p->pid, strerror(errno));
370 }
371 if (quietmode < 0 && killed) {
372 printf("stopped %s (pid", what);
373 for (p = killed; p; p = p->next)
374 printf(" %d", p->pid);
375 printf(").\n");
376 }
377 }
378
379
380 int
381 main(int argc, char **argv)
382 {
383 progname = argv[0];
384
385 parse_options(argc, argv);
386 argc -= optind;
387 argv += optind;
388
389 if (execname && stat(execname, &exec_stat))
390 fatal("stat %s: %s", execname, strerror(errno));
391
392 if (userspec && sscanf(userspec, "%d", &user_id) != 1) {
393 struct passwd *pw;
394
395 pw = getpwnam(userspec);
396 if (!pw)
397 fatal("user `%s' not found\n", userspec);
398
399 user_id = pw->pw_uid;
400 }
401
402 if (pidfile)
403 do_pidfile(pidfile);
404 else
405 do_procfs();
406
407 if (stop) {
408 do_stop();
409 exit(0);
410 }
411
412 if (found) {
413 if (quietmode <= 0)
414 printf("%s already running.\n", execname);
415 exit(exitnodo);
416 }
417 if (testmode) {
418 printf("would start %s ", startas);
419 while (argc-- > 0)
420 printf("%s ", *argv++);
421 printf(".\n");
422 exit(0);
423 }
424 if (quietmode < 0)
425 printf("starting %s ...\n", startas);
426 *--argv = startas;
427 execv(startas, argv);
428 fatal("unable to start %s: %s", startas, strerror(errno));
429 }
430