Patrick Welche <prlw1@cam.ac.uk>
[netbsd-mini2440.git] / usr.bin / at / at.c
blob076f07718937f4dfc85d4bc9ad158629224414e1
1 /* $NetBSD: at.c,v 1.26 2008/04/05 16:26:57 christos Exp $ */
3 /*
4 * at.c : Put file into atrun queue
5 * Copyright (C) 1993, 1994 Thomas Koenig
7 * Atrun & Atq modifications
8 * Copyright (C) 1993 David Parsons
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. The name of the author(s) may not be used to endorse or promote
16 * products derived from this software without specific prior written
17 * permission.
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 /* System Headers */
32 #include <sys/types.h>
33 #include <sys/param.h>
34 #include <sys/stat.h>
35 #include <sys/wait.h>
36 #include <ctype.h>
37 #include <dirent.h>
38 #include <err.h>
39 #include <errno.h>
40 #include <fcntl.h>
41 #include <locale.h>
42 #include <pwd.h>
43 #include <signal.h>
44 #include <stdbool.h>
45 #include <stddef.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <time.h>
50 #include <unistd.h>
51 #include <util.h>
53 /* Local headers */
54 #include "at.h"
55 #include "panic.h"
56 #include "parsetime.h"
57 #include "perm.h"
58 #include "pathnames.h"
59 #include "stime.h"
60 #define MAIN
61 #include "privs.h"
63 /* Macros */
64 #define ALARMC 10 /* Number of seconds to wait for timeout */
66 #define TIMESIZE 50
68 enum { ATQ, ATRM, AT, BATCH, CAT }; /* what program we want to run */
70 /* File scope variables */
71 #ifndef lint
72 #if 0
73 static char rcsid[] = "$OpenBSD: at.c,v 1.15 1998/06/03 16:20:26 deraadt Exp $";
74 #else
75 __RCSID("$NetBSD: at.c,v 1.26 2008/04/05 16:26:57 christos Exp $");
76 #endif
77 #endif
79 const char *no_export[] = {"TERM", "TERMCAP", "DISPLAY", "_"};
80 static int send_mail = 0;
82 /* External variables */
84 extern char **environ;
85 bool fcreated = false;
86 char atfile[FILENAME_MAX];
88 char *atinput = NULL; /* where to get input from */
89 unsigned char atqueue = 0; /* which queue to examine for jobs (atq) */
90 char atverify = 0; /* verify time instead of queuing job */
92 /* Function declarations */
94 static void sigc (int);
95 static void alarmc (int);
96 static char *cwdname (void);
97 static int nextjob (void);
98 static void writefile (time_t, unsigned char);
99 static void list_jobs (void);
100 static void process_jobs (int, char **, int);
102 /* Signal catching functions */
104 /*ARGSUSED*/
105 static void
106 sigc(int signo)
109 /* If a signal interrupts us, remove the spool file and exit. */
110 if (fcreated) {
111 PRIV_START;
112 (void)unlink(atfile);
113 PRIV_END;
115 (void)raise_default_signal(signo);
116 exit(EXIT_FAILURE);
119 /*ARGSUSED*/
120 static void
121 alarmc(int signo)
124 /* Time out after some seconds. */
125 warnx("File locking timed out");
126 sigc(signo);
129 /* Local functions */
131 static char *
132 cwdname(void)
136 * Read in the current directory; the name will be overwritten on
137 * subsequent calls.
139 static char path[MAXPATHLEN];
141 return getcwd(path, sizeof(path));
144 static int
145 nextjob(void)
147 int jobno;
148 FILE *fid;
150 if ((fid = fopen(_PATH_SEQFILE, "r+")) != NULL) {
151 if (fscanf(fid, "%5x", &jobno) == 1) {
152 (void)rewind(fid);
153 jobno = (1+jobno) % 0xfffff; /* 2^20 jobs enough? */
154 (void)fprintf(fid, "%05x\n", jobno);
155 } else
156 jobno = EOF;
157 (void)fclose(fid);
158 return jobno;
159 } else if ((fid = fopen(_PATH_SEQFILE, "w")) != NULL) {
160 (void)fprintf(fid, "%05x\n", jobno = 1);
161 (void)fclose(fid);
162 return 1;
164 return EOF;
167 static void
168 writefile(time_t runtimer, unsigned char queue)
171 * This does most of the work if at or batch are invoked for
172 * writing a job.
174 int jobno;
175 char *ap, *ppos;
176 const char *mailname;
177 struct passwd *pass_entry;
178 struct stat statbuf;
179 int fdes, lockdes, fd2;
180 FILE *fp, *fpin;
181 struct sigaction act;
182 char **atenv;
183 int ch;
184 mode_t cmask;
185 struct flock lock;
187 (void)setlocale(LC_TIME, "");
190 * Install the signal handler for SIGINT; terminate after removing the
191 * spool file if necessary
193 (void)memset(&act, 0, sizeof(act));
194 act.sa_handler = sigc;
195 (void)sigemptyset(&act.sa_mask);
196 act.sa_flags = 0;
198 sigaction(SIGINT, &act, NULL);
200 (void)strlcpy(atfile, _PATH_ATJOBS, sizeof(atfile));
201 ppos = atfile + strlen(atfile);
204 * Loop over all possible file names for running something at this
205 * particular time, see if a file is there; the first empty slot at
206 * any particular time is used. Lock the file _PATH_LOCKFILE first
207 * to make sure we're alone when doing this.
210 PRIV_START;
212 if ((lockdes = open(_PATH_LOCKFILE, O_WRONLY | O_CREAT, S_IWUSR | S_IRUSR)) < 0)
213 perr("Cannot open lockfile " _PATH_LOCKFILE);
215 lock.l_type = F_WRLCK;
216 lock.l_whence = SEEK_SET;
217 lock.l_start = 0;
218 lock.l_len = 0;
220 act.sa_handler = alarmc;
221 (void)sigemptyset(&act.sa_mask);
222 act.sa_flags = 0;
225 * Set an alarm so a timeout occurs after ALARMC seconds, in case
226 * something is seriously broken.
228 sigaction(SIGALRM, &act, NULL);
229 (void)alarm(ALARMC);
230 (void)fcntl(lockdes, F_SETLKW, &lock);
231 (void)alarm(0);
233 if ((jobno = nextjob()) == EOF)
234 perr("Cannot generate job number");
236 (void)snprintf(ppos, sizeof(atfile) - (ppos - atfile),
237 "%c%5x%8lx", queue, jobno, (unsigned long) (runtimer/60));
239 for (ap = ppos; *ap != '\0'; ap++)
240 if (*ap == ' ')
241 *ap = '0';
243 if (stat(atfile, &statbuf) == -1)
244 if (errno != ENOENT)
245 perr("Cannot access " _PATH_ATJOBS);
248 * Create the file. The x bit is only going to be set after it has
249 * been completely written out, to make sure it is not executed in
250 * the meantime. To make sure they do not get deleted, turn off
251 * their r bit. Yes, this is a kluge.
253 cmask = umask(S_IRUSR | S_IWUSR | S_IXUSR);
254 if ((fdes = open(atfile, O_CREAT | O_TRUNC | O_WRONLY, S_IRUSR)) == -1)
255 perr("Cannot create atjob file");
257 if ((fd2 = dup(fdes)) == -1)
258 perr("Error in dup() of job file");
260 if (fchown(fd2, real_uid, real_gid) == -1)
261 perr("Cannot give away file");
263 PRIV_END;
266 * We've successfully created the file; let's set the flag so it
267 * gets removed in case of an interrupt or error.
269 fcreated = true;
271 /* Now we can release the lock, so other people can access it */
272 lock.l_type = F_UNLCK;
273 lock.l_whence = SEEK_SET;
274 lock.l_start = 0;
275 lock.l_len = 0;
276 (void)fcntl(lockdes, F_SETLKW, &lock);
277 (void)close(lockdes);
279 if ((fp = fdopen(fdes, "w")) == NULL)
280 panic("Cannot reopen atjob file");
283 * Get the userid to mail to, first by trying getlogin(), which reads
284 * /etc/utmp, then from $LOGNAME or $USER, finally from getpwuid().
286 mailname = getlogin();
287 if (mailname == NULL && (mailname = getenv("LOGNAME")) == NULL)
288 mailname = getenv("USER");
290 if (mailname == NULL || mailname[0] == '\0' ||
291 strlen(mailname) > LOGIN_NAME_MAX || getpwnam(mailname) == NULL) {
292 pass_entry = getpwuid(real_uid);
293 if (pass_entry != NULL)
294 mailname = pass_entry->pw_name;
297 if (atinput != NULL) {
298 fpin = freopen(atinput, "r", stdin);
299 if (fpin == NULL)
300 perr("Cannot open input file");
302 (void)fprintf(fp,
303 "#!/bin/sh\n"
304 "# atrun uid=%u gid=%u\n"
305 "# mail %s %d\n",
306 real_uid, real_gid, mailname, send_mail);
308 /* Write out the umask at the time of invocation */
309 (void)fprintf(fp, "umask %o\n", cmask);
312 * Write out the environment. Anything that may look like a special
313 * character to the shell is quoted, except for \n, which is done
314 * with a pair of "'s. Dont't export the no_export list (such as
315 * TERM or DISPLAY) because we don't want these.
317 for (atenv = environ; *atenv != NULL; atenv++) {
318 int export = 1;
319 char *eqp;
321 eqp = strchr(*atenv, '=');
322 if (eqp == NULL)
323 eqp = *atenv;
324 else {
325 size_t i;
327 for (i = 0; i < __arraycount(no_export); i++) {
328 export = export &&
329 strncmp(*atenv, no_export[i],
330 (size_t)(eqp - *atenv)) != 0;
332 eqp++;
335 if (export) {
336 (void)fwrite(*atenv, sizeof(char),
337 (size_t)(eqp - *atenv), fp);
338 for (ap = eqp; *ap != '\0'; ap++) {
339 if (*ap == '\n')
340 (void)fprintf(fp, "\"\n\"");
341 else {
342 if (!isalnum((unsigned char)*ap)) {
343 switch (*ap) {
344 case '%': case '/': case '{':
345 case '[': case ']': case '=':
346 case '}': case '@': case '+':
347 case '#': case ',': case '.':
348 case ':': case '-': case '_':
349 break;
350 default:
351 (void)fputc('\\', fp);
352 break;
355 (void)fputc(*ap, fp);
358 (void)fputs("; export ", fp);
359 (void)fwrite(*atenv, sizeof(char),
360 (size_t)(eqp - *atenv - 1), fp);
361 (void)fputc('\n', fp);
365 * Cd to the directory at the time and write out all the
366 * commands the user supplies from stdin.
368 (void)fputs("cd ", fp);
369 for (ap = cwdname(); *ap != '\0'; ap++) {
370 if (*ap == '\n')
371 (void)fprintf(fp, "\"\n\"");
372 else {
373 if (*ap != '/' && !isalnum((unsigned char)*ap))
374 (void)fputc('\\', fp);
376 (void)fputc(*ap, fp);
380 * Test cd's exit status: die if the original directory has been
381 * removed, become unreadable or whatever.
383 (void)fprintf(fp,
384 " || {\n"
385 "\t echo 'Execution directory inaccessible' >&2\n"
386 "\t exit 1\n"
387 "}\n");
389 if ((ch = getchar()) == EOF)
390 panic("Input error");
392 do {
393 (void)fputc(ch, fp);
394 } while ((ch = getchar()) != EOF);
396 (void)fprintf(fp, "\n");
397 if (ferror(fp))
398 panic("Output error");
400 if (ferror(stdin))
401 panic("Input error");
403 (void)fclose(fp);
405 PRIV_START;
408 * Set the x bit so that we're ready to start executing
410 if (fchmod(fd2, S_IRUSR | S_IWUSR | S_IXUSR) == -1)
411 perr("Cannot give away file");
413 PRIV_END;
415 (void)close(fd2);
416 (void)fprintf(stderr,
417 "Job %d will be executed using /bin/sh\n", jobno);
420 static void
421 list_jobs(void)
424 * List all a user's jobs in the queue, by looping through
425 * _PATH_ATJOBS, or everybody's if we are root
427 struct passwd *pw;
428 DIR *spool;
429 struct dirent *dirent;
430 struct stat buf;
431 struct tm runtime;
432 unsigned long ctm;
433 unsigned char queue;
434 int jobno;
435 time_t runtimer;
436 char timestr[TIMESIZE];
437 int first = 1;
439 PRIV_START;
441 if (chdir(_PATH_ATJOBS) == -1)
442 perr("Cannot change to " _PATH_ATJOBS);
444 if ((spool = opendir(".")) == NULL)
445 perr("Cannot open " _PATH_ATJOBS);
447 /* Loop over every file in the directory */
448 while ((dirent = readdir(spool)) != NULL) {
449 if (stat(dirent->d_name, &buf) == -1)
450 perr("Cannot stat in " _PATH_ATJOBS);
453 * See it's a regular file and has its x bit turned on and
454 * is the user's
456 if (!S_ISREG(buf.st_mode)
457 || (buf.st_uid != real_uid && real_uid != 0)
458 || !(S_IXUSR & buf.st_mode || atverify))
459 continue;
461 if (sscanf(dirent->d_name, "%c%5x%8lx", &queue, &jobno, &ctm) != 3)
462 continue;
464 if (atqueue && queue != atqueue)
465 continue;
467 runtimer = 60 * (time_t)ctm;
468 runtime = *localtime(&runtimer);
469 (void)strftime(timestr, TIMESIZE, "%X %x", &runtime);
470 if (first) {
471 (void)printf("%-*s %-*s %-*s %s\n",
472 (int)strlen(timestr), "Date",
473 LOGIN_NAME_MAX, "Owner",
474 7, "Queue",
475 "Job");
476 first = 0;
478 pw = getpwuid(buf.st_uid);
480 (void)printf("%s %-*s %c%-*s %d\n",
481 timestr,
482 LOGIN_NAME_MAX, pw ? pw->pw_name : "???",
483 queue,
484 6, (S_IXUSR & buf.st_mode) ? "" : "(done)",
485 jobno);
487 PRIV_END;
490 static void
491 process_jobs(int argc, char **argv, int what)
493 /* Delete every argument (job - ID) given */
494 int i;
495 struct stat buf;
496 DIR *spool;
497 struct dirent *dirent;
498 unsigned long ctm;
499 unsigned char queue;
500 int jobno;
502 PRIV_START;
504 if (chdir(_PATH_ATJOBS) == -1)
505 perr("Cannot change to " _PATH_ATJOBS);
507 if ((spool = opendir(".")) == NULL)
508 perr("Cannot open " _PATH_ATJOBS);
510 PRIV_END;
512 /* Loop over every file in the directory */
513 while((dirent = readdir(spool)) != NULL) {
515 PRIV_START;
516 if (stat(dirent->d_name, &buf) == -1)
517 perr("Cannot stat in " _PATH_ATJOBS);
518 PRIV_END;
520 if (sscanf(dirent->d_name, "%c%5x%8lx", &queue, &jobno, &ctm) !=3)
521 continue;
523 for (i = optind; i < argc; i++) {
524 if (atoi(argv[i]) == jobno) {
525 if (buf.st_uid != real_uid && real_uid != 0)
526 errx(EXIT_FAILURE,
527 "%s: Not owner", argv[i]);
529 switch (what) {
530 case ATRM:
531 PRIV_START;
533 if (unlink(dirent->d_name) == -1)
534 perr(dirent->d_name);
536 PRIV_END;
537 break;
539 case CAT: {
540 FILE *fp;
541 int ch;
543 PRIV_START;
545 fp = fopen(dirent->d_name, "r");
547 PRIV_END;
549 if (!fp)
550 perr("Cannot open file");
551 else {
552 while((ch = getc(fp)) != EOF)
553 (void)putchar(ch);
554 (void)fclose(fp);
557 break;
559 default:
560 errx(EXIT_FAILURE,
561 "Internal error, process_jobs = %d",
562 what);
563 break;
570 /* Global functions */
573 main(int argc, char **argv)
575 int c;
576 unsigned char queue = DEFAULT_AT_QUEUE;
577 char queue_set = 0;
578 char time_set = 0;
579 char *pgm;
581 int program = AT; /* our default program */
582 const char *options = "q:f:t:mvldbrVc"; /* default options for at */
583 int disp_version = 0;
584 time_t timer;
586 RELINQUISH_PRIVS;
588 /* Eat any leading paths */
589 if ((pgm = strrchr(argv[0], '/')) == NULL)
590 pgm = argv[0];
591 else
592 pgm++;
594 /* find out what this program is supposed to do */
595 if (strcmp(pgm, "atq") == 0) {
596 program = ATQ;
597 options = "q:vV";
598 } else if (strcmp(pgm, "atrm") == 0) {
599 program = ATRM;
600 options = "V";
601 } else if (strcmp(pgm, "batch") == 0) {
602 program = BATCH;
603 options = "f:q:t:mvV";
606 /* process whatever options we can process */
607 opterr = 1;
608 while ((c = getopt(argc, argv, options)) != -1) {
609 switch (c) {
610 case 'v': /* verify time settings */
611 atverify = 1;
612 break;
614 case 'm': /* send mail when job is complete */
615 send_mail = 1;
616 break;
618 case 'f':
619 atinput = optarg;
620 break;
622 case 'q': /* specify queue */
623 if (strlen(optarg) > 1)
624 usage();
626 atqueue = queue = *optarg;
627 if (!(islower(queue) || isupper(queue)))
628 usage();
630 queue_set = 1;
631 break;
632 case 't': /* touch(1) date format */
633 timer = stime(optarg);
634 time_set = 1;
635 break;
637 case 'd':
638 case 'r':
639 if (program != AT)
640 usage();
642 program = ATRM;
643 options = "V";
644 break;
646 case 'l':
647 if (program != AT)
648 usage();
650 program = ATQ;
651 options = "q:vV";
652 break;
654 case 'b':
655 if (program != AT)
656 usage();
658 program = BATCH;
659 options = "f:q:mvV";
660 break;
662 case 'V':
663 disp_version = 1;
664 break;
666 case 'c':
667 program = CAT;
668 options = "";
669 break;
671 default:
672 usage();
673 break;
675 } /* end of options eating */
677 if (disp_version)
678 (void)fprintf(stderr, "%s version %.1f\n", pgm, AT_VERSION);
680 if (!check_permission())
681 errx(EXIT_FAILURE,
682 "You do not have permission to use %s.", pgm);
684 /* select our program */
685 switch (program) {
686 case ATQ:
687 if (optind != argc)
688 usage();
689 list_jobs();
690 break;
692 case ATRM:
693 case CAT:
694 if (optind == argc)
695 usage();
696 process_jobs(argc, argv, program);
697 break;
699 case AT:
700 if (argc > optind) {
701 /* -t and timespec argument are mutually exclusive */
702 if (time_set) {
703 usage();
704 exit(EXIT_FAILURE);
705 } else {
706 timer = parsetime(argc, argv);
707 time_set = 1;
711 if (atverify) {
712 struct tm *tm = localtime(&timer);
713 (void)fprintf(stderr, "%s\n", asctime(tm));
715 writefile(timer, queue);
716 break;
718 case BATCH:
719 if (queue_set)
720 queue = toupper(queue);
721 else
722 queue = DEFAULT_BATCH_QUEUE;
724 if (argc > optind) {
725 /* -t and timespec argument are mutually exclusive */
726 if (time_set) {
727 usage();
728 exit(EXIT_FAILURE);
729 } else {
730 timer = parsetime(argc, argv);
731 time_set = 1;
733 } else if (!time_set)
734 timer = time(NULL);
736 if (atverify) {
737 struct tm *tm = localtime(&timer);
738 (void)fprintf(stderr, "%s\n", asctime(tm));
741 writefile(timer, queue);
742 break;
744 default:
745 panic("Internal error");
746 break;
748 return EXIT_SUCCESS;