usr/src/usr.bin/touch/touch.c

/*
 * Copyright (c) 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * 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. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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, WHETHER 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.
 */

#ifndef lint
static char copyright[] =
"@(#) Copyright (c) 1993\n\
        The Regents of the University of California.  All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)touch.c     8.2 (Berkeley) 4/28/95";
#endif /* not lint */

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>

#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

int     rw __P((char *, struct stat *, int));
void    stime_arg1 __P((char *, struct timeval *));
void    stime_arg2 __P((char *, int, struct timeval *));
void    stime_file __P((char *, struct timeval *));
void    usage __P((void));

int
main(argc, argv)
        int argc;
        char *argv[];
{
        struct stat sb;
        struct timeval tv[2];
        int aflag, cflag, fflag, mflag, ch, fd, len, rval, timeset;
        char *p;

        aflag = cflag = fflag = mflag = timeset = 0;
        if (gettimeofday(&tv[0], NULL))
                err(1, "gettimeofday");

        while ((ch = getopt(argc, argv, "acfmr:t:")) != EOF)
                switch(ch) {
                case 'a':
                        aflag = 1;
                        break;
                case 'c':
                        cflag = 1;
                        break;
                case 'f':
                        fflag = 1;
                        break;
                case 'm':
                        mflag = 1;
                        break;
                case 'r':
                        timeset = 1;
                        stime_file(optarg, tv);
                        break;
                case 't':
                        timeset = 1;
                        stime_arg1(optarg, tv);
                        break;
                case '?':
                default:
                        usage();
                }
        argc -= optind;
        argv += optind;

        /* Default is both -a and -m. */
        if (aflag == 0 && mflag == 0)
                aflag = mflag = 1;

        /*
         * If no -r or -t flag, at least two operands, the first of which
         * is an 8 or 10 digit number, use the obsolete time specification.
         */
        if (!timeset && argc > 1) {
                (void)strtol(argv[0], &p, 10);
                len = p - argv[0];
                if (*p == '\0' && (len == 8 || len == 10)) {
                        timeset = 1;
                        stime_arg2(*argv++, len == 10, tv);
                }
        }

        /* Otherwise use the current time of day. */
        if (!timeset)
                tv[1] = tv[0];

        if (*argv == NULL)
                usage();

        for (rval = 0; *argv; ++argv) {
                /* See if the file exists. */
                if (stat(*argv, &sb))
                        if (!cflag) {
                                /* Create the file. */
                                fd = open(*argv,
                                    O_WRONLY | O_CREAT, DEFFILEMODE);
                                if (fd == -1 || fstat(fd, &sb) || close(fd)) {
                                        rval = 1;
                                        warn("%s", *argv);
                                        continue;
                                }

                                /* If using the current time, we're done. */
                                if (!timeset)
                                        continue;
                        } else
                                continue;

                if (!aflag)
                        TIMESPEC_TO_TIMEVAL(&tv[0], &sb.st_atimespec);
                if (!mflag)
                        TIMESPEC_TO_TIMEVAL(&tv[1], &sb.st_mtimespec);

                /* Try utimes(2). */
                if (!utimes(*argv, tv))
                        continue;

                /* If the user specified a time, nothing else we can do. */
                if (timeset) {
                        rval = 1;
                        warn("%s", *argv);
                }

                /*
                 * System V and POSIX 1003.1 require that a NULL argument
                 * set the access/modification times to the current time.
                 * The permission checks are different, too, in that the
                 * ability to write the file is sufficient.  Take a shot.
                 */
                 if (!utimes(*argv, NULL))
                        continue;

                /* Try reading/writing. */
                if (rw(*argv, &sb, fflag))
                        rval = 1;
        }
        exit(rval);
}

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

void
stime_arg1(arg, tvp)
        char *arg;
        struct timeval *tvp;
{
        struct tm *t;
        int yearset;
        char *p;
                                        /* Start with the current time. */
        if ((t = localtime(&tvp[0].tv_sec)) == NULL)
                err(1, "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;
                /* FALLTHOUGH */
        case 10:                        /* YYMMDDhhmm */
                if (yearset) {
                        yearset = ATOI2(arg);
                        t->tm_year += yearset;
                } else {
                        yearset = ATOI2(arg);
                        if (yearset < 69)
                                t->tm_year = yearset + 2000;
                        else
                                t->tm_year = yearset + 1900;
                }
                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. */
        tvp[0].tv_sec = tvp[1].tv_sec = mktime(t);
        if (tvp[0].tv_sec == -1)
terr:           errx(1,
        "out of range or illegal time specification: [[CC]YY]MMDDhhmm[.SS]");

        tvp[0].tv_usec = tvp[1].tv_usec = 0;
}

void
stime_arg2(arg, year, tvp)
        char *arg;
        int year;
        struct timeval *tvp;
{
        struct tm *t;
                                        /* Start with the current time. */
        if ((t = localtime(&tvp[0].tv_sec)) == NULL)
                err(1, "localtime");

        t->tm_mon = ATOI2(arg);         /* MMDDhhmm[yy] */
        --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);
        if (year)
                t->tm_year = ATOI2(arg);

        t->tm_isdst = -1;               /* Figure out DST. */
        tvp[0].tv_sec = tvp[1].tv_sec = mktime(t);
        if (tvp[0].tv_sec == -1)
                errx(1,
        "out of range or illegal time specification: MMDDhhmm[yy]");

        tvp[0].tv_usec = tvp[1].tv_usec = 0;
}

void
stime_file(fname, tvp)
        char *fname;
        struct timeval *tvp;
{
        struct stat sb;

        if (stat(fname, &sb))
                err(1, "%s", fname);
        TIMESPEC_TO_TIMEVAL(tvp, &sb.st_atimespec);
        TIMESPEC_TO_TIMEVAL(tvp + 1, &sb.st_mtimespec);
}

int
rw(fname, sbp, force)
        char *fname;
        struct stat *sbp;
        int force;
{
        int fd, needed_chmod, rval;
        u_char byte;

        /* Try regular files and directories. */
        if (!S_ISREG(sbp->st_mode) && !S_ISDIR(sbp->st_mode)) {
                warnx("%s: %s", fname, strerror(EFTYPE));
                return (1);
        }

        needed_chmod = rval = 0;
        if ((fd = open(fname, O_RDWR, 0)) == -1) {
                if (!force || chmod(fname, DEFFILEMODE))
                        goto err;
                if ((fd = open(fname, O_RDWR, 0)) == -1)
                        goto err;
                needed_chmod = 1;
        }

        if (sbp->st_size != 0) {
                if (read(fd, &byte, sizeof(byte)) != sizeof(byte))
                        goto err;
                if (lseek(fd, (off_t)0, SEEK_SET) == -1)
                        goto err;
                if (write(fd, &byte, sizeof(byte)) != sizeof(byte))
                        goto err;
        } else {
                if (write(fd, &byte, sizeof(byte)) != sizeof(byte)) {
err:                    rval = 1;
                        warn("%s", fname);
                } else if (ftruncate(fd, (off_t)0)) {
                        rval = 1;
                        warn("%s: file modified", fname);
                }
        }

        if (close(fd) && rval != 1) {
                rval = 1;
                warn("%s", fname);
        }
        if (needed_chmod && chmod(fname, sbp->st_mode) && rval != 1) {
                rval = 1;
                warn("%s: permissions modified", fname);
        }
        return (rval);
}

__dead void
usage()
{
        (void)fprintf(stderr,
            "usage: touch [-acfm] [-r file] [-t time] file ...\n");
        exit(1);
}