Return to at.c CVS log

Up to [local] / src / usr.bin / at

Only print usage for the command that was run (at, atq, atrm, batch), not
all four.  Also differentiate between the touch(1) style time as time_arg
and the at(1) style time as timespec (which is what SUS3 does).
Instead of referring to the touch time format as POSIX time, reference
touch.  This is what SUS3 does and it is what users will know.

/*	$OpenBSD: at.c,v 1.27 2002/05/13 16:12:07 millert Exp $	*/
/*	$NetBSD: at.c,v 1.4 1995/03/25 18:13:31 glass Exp $	*/

/*
 *  at.c : Put file into atrun queue
 *  Copyright (C) 1993, 1994  Thomas Koenig
 *
 *  Atrun & Atq modifications
 *  Copyright (C) 1993  David Parsons
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. The name of the author(s) may not be used to endorse or promote
 *    products derived from this software without specific prior written
 *    permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/* System Headers */
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <pwd.h>
#include <signal.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <utmp.h>
#include <locale.h>
#include <err.h>

#if (MAXLOGNAME-1) > UT_NAMESIZE
#define LOGNAMESIZE UT_NAMESIZE
#else
#define LOGNAMESIZE (MAXLOGNAME-1)
#endif

/* Local headers */
#include "at.h"
#include "panic.h"
#include "parsetime.h"
#include "perm.h"
#include "pathnames.h"
#define MAIN
#include "privs.h"

/* Macros */
#define ALARMC 10		/* Number of seconds to wait for timeout */

#define TIMESIZE 50

/* File scope variables */
#ifndef lint
static const char rcsid[] = "$OpenBSD: at.c,v 1.27 2002/05/13 16:12:07 millert Exp $";
#endif

char *no_export[] =
{
	"TERM", "TERMCAP", "DISPLAY", "_"
};
static int send_mail = 0;

/* External variables */

extern char **environ;
int fcreated;
int program = AT;		/* default program mode */
char atfile[FILENAME_MAX];

char *atinput = (char *)0;	/* where to get input from */
char atqueue = 0;		/* which queue to examine for jobs (atq) */
char atverify = 0;		/* verify time instead of queuing job */

/* Function declarations */

static void sigc(int);
static void alarmc(int);
static char *cwdname(void);
static void writefile(time_t, char);
static void list_jobs(void);
static time_t ttime(const char *);

/* Signal catching functions */

static void 
sigc(int signo)
{
	/* If the user presses ^C, remove the spool file and exit. */
	if (fcreated) {
		PRIV_START;
		(void)unlink(atfile);
		PRIV_END;
	}

	_exit(EXIT_FAILURE);
}

static void 
alarmc(int signo)
{
	char buf[1024];

	/* Time out after some seconds. */
	strlcpy(buf, __progname, sizeof(buf));
	strlcat(buf, ": File locking timed out\n", sizeof(buf));
	write(STDERR_FILENO, buf, strlen(buf));
	if (fcreated) {
		PRIV_START;
		unlink(atfile);
		PRIV_END;
	}
	_exit(EXIT_FAILURE);
}

/* Local functions */

static char *
cwdname(void)
{
	/*
	 * Read in the current directory; the name will be overwritten on
	 * subsequent calls.
	 */
	static char path[MAXPATHLEN];

	return (getcwd(path, sizeof(path)));
}

static int
nextjob(void)
{
	int jobno;
	FILE *fid;

	/* We require that the sequence file already exist. */
	if ((fid = fopen(_PATH_SEQFILE, "r+")) == NULL)
		return (EOF);

	if (fscanf(fid, "%5x", &jobno) == 1)
		jobno = (jobno + 1) % 0xfffff;	/* 2^20 jobs enough? */
	else
		jobno = 1;
	(void)rewind(fid);
	(void)fprintf(fid, "%05x\n", jobno);
	(void)fclose(fid);

	return (jobno);
}

static void
writefile(time_t runtimer, char queue)
{
	/*
	 * This does most of the work if at or batch are invoked for
	 * writing a job.
	 */
	int jobno;
	char *ap, *ppos, *mailname;
	struct passwd *pass_entry;
	struct stat statbuf;
	int fdes, lockdes, fd2;
	FILE *fp, *fpin;
	struct sigaction act;
	char **atenv;
	int ch;
	mode_t cmask;
	struct flock lock;

	(void)setlocale(LC_TIME, "");

	/*
	 * Install the signal handler for SIGINT; terminate after removing the
	 * spool file if necessary
	 */
	memset(&act, 0, sizeof act);
	act.sa_handler = sigc;
	sigemptyset(&(act.sa_mask));
	act.sa_flags = 0;

	sigaction(SIGINT, &act, NULL);

	(void)strlcpy(atfile, _PATH_ATJOBS, sizeof atfile);
	ppos = atfile + strlen(atfile);

	/*
	 * Loop over all possible file names for running something at this
	 * particular time, see if a file is there; the first empty slot at
	 * any particular time is used.  Lock the jobs directory first
	 * to make sure we're alone when doing this.
	 */

	PRIV_START;

	/*
	 * Set an alarm so we don't sleep forever waiting on the lock.
	 * If we don't succeed with ALARMC seconds, something is wrong...
	 */
	act.sa_handler = alarmc;
	sigemptyset(&(act.sa_mask));
	act.sa_flags = 0;
	sigaction(SIGALRM, &act, NULL);
	alarm(ALARMC);
	lockdes = open(_PATH_ATJOBS, O_RDONLY|O_EXLOCK, 0);
	alarm(0);

	if (lockdes < 0)
		perr("Cannot lock jobs dir");

	if ((jobno = nextjob()) == EOF)
		perr("Cannot generate job number");

	(void)snprintf(ppos, sizeof(atfile) - (ppos - atfile),
	    "%c%5x%8x", queue, jobno, (unsigned) (runtimer/60));

	for (ap = ppos; *ap != '\0'; ap++)
		if (*ap == ' ')
			*ap = '0';

	if (stat(atfile, &statbuf) != 0)
		if (errno != ENOENT)
			perr2("Cannot access ", _PATH_ATJOBS);

	/*
	 * Create the file. The x bit is only going to be set after it has
	 * been completely written out, to make sure it is not executed in
	 * the meantime.  To make sure they do not get deleted, turn off
	 * their r bit.  Yes, this is a kluge.
	 */
	cmask = umask(S_IRUSR | S_IWUSR | S_IXUSR);
	if ((fdes = open(atfile, O_WRONLY | O_CREAT | O_EXCL, S_IRUSR)) == -1)
		perr("Cannot create atjob file");

	if ((fd2 = dup(fdes)) < 0)
		perr("Error in dup() of job file");

	if (fchown(fd2, real_uid, real_gid) != 0)
		perr("Cannot give away file");

	PRIV_END;

	/*
	 * We've successfully created the file; let's set the flag so it
	 * gets removed in case of an interrupt or error.
	 */
	fcreated = 1;

	/* Now we can release the lock, so other people can access it */
	lock.l_type = F_UNLCK;
	lock.l_whence = SEEK_SET;
	lock.l_start = 0;
	lock.l_len = 0;
	(void)fcntl(lockdes, F_SETLKW, &lock);
	(void)close(lockdes);

	if ((fp = fdopen(fdes, "w")) == NULL)
		panic("Cannot reopen atjob file");

	/*
	 * Get the userid to mail to, first by trying getlogin(), which asks
	 * the kernel, then from $LOGNAME or $USER, finally from getpwuid().
	 */
	mailname = getlogin();
	if (mailname == NULL && (mailname = getenv("LOGNAME")) == NULL)
		mailname = getenv("USER");

	if ((mailname == NULL) || (mailname[0] == '\0') ||
	    (strlen(mailname) > LOGNAMESIZE) || (getpwnam(mailname) == NULL)) {
		pass_entry = getpwuid(real_uid);
		if (pass_entry != NULL)
			mailname = pass_entry->pw_name;
	}

	if (atinput != NULL) {
		fpin = freopen(atinput, "r", stdin);
		if (fpin == NULL)
			perr("Cannot open input file");
	}
	(void)fprintf(fp, "#!/bin/sh\n# atrun uid=%u gid=%u\n# mail %*s %d\n",
	    real_uid, real_gid, LOGNAMESIZE, mailname, send_mail);

	/* Write out the umask at the time of invocation */
	(void)fprintf(fp, "umask %o\n", cmask);

	/*
	 * Write out the environment. Anything that may look like a special
	 * character to the shell is quoted, except for \n, which is done
	 * with a pair of "'s.  Dont't export the no_export list (such as
	 * TERM or DISPLAY) because we don't want these.
	 */
	for (atenv = environ; *atenv != NULL; atenv++) {
		int export = 1;
		char *eqp;

		eqp = strchr(*atenv, '=');
		if (eqp == NULL)
			eqp = *atenv;
		else {
			int i;

			for (i = 0;i < sizeof(no_export) /
			    sizeof(no_export[0]); i++) {
				export = export
				    && (strncmp(*atenv, no_export[i],
					(size_t) (eqp - *atenv)) != 0);
			}
			eqp++;
		}

		if (export) {
			(void)fwrite(*atenv, sizeof(char), eqp - *atenv, fp);
			for (ap = eqp; *ap != '\0'; ap++) {
				if (*ap == '\n')
					(void)fprintf(fp, "\"\n\"");
				else {
					if (!isalnum(*ap)) {
						switch (*ap) {
						case '%': case '/': case '{':
						case '[': case ']': case '=':
						case '}': case '@': case '+':
						case '#': case ',': case '.':
						case ':': case '-': case '_':
							break;
						default:
							(void)fputc('\\', fp);
							break;
						}
					}
					(void)fputc(*ap, fp);
				}
			}
			(void)fputs("; export ", fp);
			(void)fwrite(*atenv, sizeof(char), eqp - *atenv - 1, fp);
			(void)fputc('\n', fp);
		}
	}
	/*
	 * Cd to the directory at the time and write out all the
	 * commands the user supplies from stdin.
	 */
	if ((ap = cwdname()) == NULL)
		perr("Cannot get current working directory");
	(void)fputs("cd ", fp);
	for (; *ap != '\0'; ap++) {
		if (*ap == '\n')
			fprintf(fp, "\"\n\"");
		else {
			if (*ap != '/' && !isalnum(*ap))
				(void)fputc('\\', fp);

			(void)fputc(*ap, fp);
		}
	}
	/*
	 * Test cd's exit status: die if the original directory has been
	 * removed, become unreadable or whatever.
	 */
	(void)fprintf(fp, " || {\n\t echo 'Execution directory inaccessible' >&2\n\t exit 1\n}\n");

	if ((ch = getchar()) == EOF)
		panic("Input error");

	do {
		(void)fputc(ch, fp);
	} while ((ch = getchar()) != EOF);

	(void)fprintf(fp, "\n");
	if (ferror(fp))
		panic("Output error");

	if (ferror(stdin))
		panic("Input error");

	(void)fclose(fp);

	/*
	 * Set the x bit so that we're ready to start executing
	 */
	if (fchmod(fd2, S_IRUSR | S_IWUSR | S_IXUSR) < 0)
		perr("Cannot give away file");

	(void)close(fd2);
	(void)fprintf(stderr, "Job %d will be executed using /bin/sh\n", jobno);
}

static void
list_jobs(void)
{
	/*
	 * List all a user's jobs in the queue, by looping through
	 * _PATH_ATJOBS, or everybody's if we are root
	 */
	struct passwd *pw;
	DIR *spool;
	struct dirent *dirent;
	struct stat buf;
	struct tm runtime;
	unsigned long ctm;
	char queue;
	int jobno;
	time_t runtimer;
	char timestr[TIMESIZE];
	int first = 1;

	PRIV_START;

	if (chdir(_PATH_ATJOBS) != 0)
		perr2("Cannot change to ", _PATH_ATJOBS);

	if ((spool = opendir(".")) == NULL)
		perr2("Cannot open ", _PATH_ATJOBS);

	/* Loop over every file in the directory */
	while ((dirent = readdir(spool)) != NULL) {
		if (stat(dirent->d_name, &buf) != 0)
			perr2("Cannot stat in ", _PATH_ATJOBS);

		/*
		 * See it's a regular file and has its x bit turned on and
		 * is the user's
		 */
		if (!S_ISREG(buf.st_mode)
		    || ((buf.st_uid != real_uid) && !(real_uid == 0))
		    || !(S_IXUSR & buf.st_mode || atverify))
			continue;

		if (sscanf(dirent->d_name, "%c%5x%8lx", &queue, &jobno, &ctm) != 3)
			continue;

		if (atqueue && (queue != atqueue))
			continue;

		runtimer = 60 * (time_t) ctm;
		runtime = *localtime(&runtimer);
		strftime(timestr, TIMESIZE, "%a %b %e %T %Y", &runtime);
		if (first) {
			(void)printf("Date\t\t\t\tOwner\t\tQueue\tJob#\n");
			first = 0;
		}
		pw = getpwuid(buf.st_uid);

		(void)printf("%s\t%-16s%c%s\t%d\n",
		    timestr,
		    pw ? pw->pw_name : "???",
		    queue,
		    (S_IXUSR & buf.st_mode) ? "" : "(done)",
		    jobno);
	}
	PRIV_END;
}

static void
process_jobs(int argc, char **argv, int what)
{
	/* Delete every argument (job - ID) given */
	int i;
	struct stat buf;
	DIR *spool;
	struct dirent *dirent;
	unsigned long ctm;
	char queue;
	int jobno;

	PRIV_START;

	if (chdir(_PATH_ATJOBS) != 0)
		perr2("Cannot change to ", _PATH_ATJOBS);

	if ((spool = opendir(".")) == NULL)
		perr2("Cannot open ", _PATH_ATJOBS);

	PRIV_END;

	/* Loop over every file in the directory */
	while((dirent = readdir(spool)) != NULL) {

		PRIV_START;
		if (stat(dirent->d_name, &buf) != 0)
			perr2("Cannot stat in ", _PATH_ATJOBS);
		PRIV_END;

		if (sscanf(dirent->d_name, "%c%5x%8lx", &queue, &jobno, &ctm) !=3)
			continue;

		for (i = optind; i < argc; i++) {
			if (atoi(argv[i]) == jobno) {
				if ((buf.st_uid != real_uid) && !(real_uid == 0))
					errx(EXIT_FAILURE,
					     "%s: Not owner\n", argv[i]);
				switch (what) {
				case ATRM:
					PRIV_START;

					if (unlink(dirent->d_name) != 0)
						perr(dirent->d_name);

					PRIV_END;

					break;

				case CAT:
					{
						FILE *fp;
						int ch;

						PRIV_START;

						fp = fopen(dirent->d_name, "r");

						PRIV_END;

						if (!fp)
							perr("Cannot open file");

						while((ch = getc(fp)) != EOF)
							putchar(ch);
					}
					break;

				default:
					errx(EXIT_FAILURE,
					    "Internal error, process_jobs = %d",
					    what);
					break;
				}
			}
		}
	}
}				/* delete_jobs */

#define	ATOI2(s)	((s) += 2, ((s)[-2] - '0') * 10 + ((s)[-1] - '0'))

static time_t
ttime(const char *arg)
{
	/*
	 * This is pretty much a copy of stime_arg1() from touch.c.  I changed
	 * the return value and the argument list because it's more convenient
	 * (IMO) to do everything in one place. - Joe Halpin
	 */
	struct timeval tv[2];
	time_t now;
	struct tm *t;
	int yearset;
	char *p;
	
	if (gettimeofday(&tv[0], NULL))
		panic("Cannot get current time");
	
	/* Start with the current time. */
	now = tv[0].tv_sec;
	if ((t = localtime(&now)) == NULL)
		panic("localtime");
	/* [[CC]YY]MMDDhhmm[.SS] */
	if ((p = strchr(arg, '.')) == NULL)
		t->tm_sec = 0;		/* Seconds defaults to 0. */
	else {
		if (strlen(p + 1) != 2)
			goto terr;
		*p++ = '\0';
		t->tm_sec = ATOI2(p);
	}
	
	yearset = 0;
	switch(strlen(arg)) {
	case 12:			/* CCYYMMDDhhmm */
		t->tm_year = ATOI2(arg);
		t->tm_year *= 100;
		yearset = 1;
		/* FALLTHROUGH */
	case 10:			/* YYMMDDhhmm */
		if (yearset) {
			yearset = ATOI2(arg);
			t->tm_year += yearset;
		} else {
			yearset = ATOI2(arg);
			t->tm_year = yearset + 2000;
		}
		t->tm_year -= 1900;	/* Convert to UNIX time. */
		/* FALLTHROUGH */
	case 8:				/* MMDDhhmm */
		t->tm_mon = ATOI2(arg);
		--t->tm_mon;		/* Convert from 01-12 to 00-11 */
		t->tm_mday = ATOI2(arg);
		t->tm_hour = ATOI2(arg);
		t->tm_min = ATOI2(arg);
		break;
	default:
		goto terr;
	}
	
	t->tm_isdst = -1;		/* Figure out DST. */
	tv[0].tv_sec = tv[1].tv_sec = mktime(t);
	if (tv[0].tv_sec != -1)
		return (tv[0].tv_sec);
	else
    terr:
		panic("out of range or illegal time specification: "
		    "[[CC]YY]MMDDhhmm[.SS]");
}

/* Global functions */

int
main(int argc, char **argv)
{
	int c;
	char queue = DEFAULT_AT_QUEUE;
	char queue_set = 0;
	char *options = "q:f:t:bcdlmrv";	/* default options for at */
	time_t timer;
	int tflag = 0;

	RELINQUISH_PRIVS;

	/* find out what this program is supposed to do */
	if (strcmp(__progname, "atq") == 0) {
		program = ATQ;
		options = "q:v";
	} else if (strcmp(__progname, "atrm") == 0) {
		program = ATRM;
		options = "";
	} else if (strcmp(__progname, "batch") == 0) {
		program = BATCH;
		options = "f:q:mv";
	}

	/* process whatever options we can process */
	opterr = 1;
	while ((c = getopt(argc, argv, options)) != -1)
		switch (c) {
		case 'v':	/* verify time settings */
			atverify = 1;
			break;

		case 'm':	/* send mail when job is complete */
			send_mail = 1;
			break;

		case 'f':
			atinput = optarg;
			break;

		case 'q':	/* specify queue */
			if (strlen(optarg) > 1)
				usage();

			atqueue = queue = *optarg;
			if (!(islower(queue) || isupper(queue)))
				usage();

			queue_set = 1;
			break;

		case 'd':		/* for backwards compatibility */
		case 'r':
			if (program != AT)
				usage();

			program = ATRM;
			options = "";
			break;

		case 't':
			if (program != AT)
				usage();
			tflag++;
			timer = ttime(optarg);
			break;

		case 'l':
			if (program != AT)
				usage();

			program = ATQ;
			options = "q:v";
			break;

		case 'b':
			if (program != AT)
				usage();

			program = BATCH;
			options = "f:q:mv";
			break;

		case 'c':
			program = CAT;
			options = "";
			break;

		default:
			usage();
			break;
		}
	/* end of options eating */

	if (!check_permission())
		errx(EXIT_FAILURE, "You do not have permission to use %s.",
		     __progname);

	/* select our program */
	switch (program) {
	case ATQ:
		if (optind != argc)
			usage();
		list_jobs();
		break;

	case ATRM:
	case CAT:
		if (optind == argc)
			usage();
		process_jobs(argc, argv, program);
		break;

	case AT:
		/* Time may have been specified via the -t flag. */
		if (!tflag)
			timer = parsetime(argc, argv);
		if (atverify) {
			struct tm *tm = localtime(&timer);
			(void)fprintf(stderr, "%s\n", asctime(tm));
		}
		writefile(timer, queue);
		break;

	case BATCH:
		if (queue_set)
			queue = toupper(queue);
		else
			queue = DEFAULT_BATCH_QUEUE;

		if (argc > optind)
			timer = parsetime(argc, argv);
		else
			timer = time(NULL);

		if (atverify) {
			struct tm *tm = localtime(&timer);
			(void)fprintf(stderr, "%s\n", asctime(tm));
		}

		writefile(timer, queue);
		break;

	default:
		panic("Internal error");
		break;
	}
	exit(EXIT_SUCCESS);
}