usr.bin/touch/touch.c

   1 /*
   2  * Copyright (c) 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * @(#) Copyright (c) 1993 The Regents of the University of California.  All rights reserved.
  34  * @(#)touch.c  8.1 (Berkeley) 6/6/93
  35  * $FreeBSD: src/usr.bin/touch/touch.c,v 1.11.2.2 2002/07/28 06:52:15 eric Exp $
  36  * $DragonFly: src/usr.bin/touch/touch.c,v 1.8 2004/09/14 00:13:36 drhodus Exp $
  37  */
  38
  39 #include <sys/types.h>
  40 #include <sys/stat.h>
  41 #include <sys/time.h>
  42
  43 #include <err.h>
  44 #include <errno.h>
  45 #include <fcntl.h>
  46 #include <stdio.h>
  47 #include <stdlib.h>
  48 #include <string.h>
  49 #include <time.h>
  50 #include <unistd.h>
  51
  52 static int      rw(const char *, const struct stat *, int);
  53 static void     stime_arg1(const char *, struct timeval *);
  54 static void     stime_arg2(const char *, int, struct timeval *);
  55 static void     stime_file(const char *, struct timeval *);
  56 static void     usage(void);
  57
  58 int
  59 main(int argc, char **argv)
  60 {
  61         struct stat sb;
  62         struct timeval tv[2];
  63         int aflag, cflag, fflag, mflag, ch, fd, len, rval, timeset;
  64         char *p;
  65
  66         aflag = cflag = fflag = mflag = timeset = 0;
  67         if (gettimeofday(&tv[0], NULL) == -1)
  68                 err(1, "gettimeofday");
  69
  70         while ((ch = getopt(argc, argv, "acfmr:t:")) != -1)
  71                 switch(ch) {
  72                 case 'a':
  73                         aflag = 1;
  74                         break;
  75                 case 'c':
  76                         cflag = 1;
  77                         break;
  78                 case 'f':
  79                         fflag = 1;
  80                         break;
  81                 case 'm':
  82                         mflag = 1;
  83                         break;
  84                 case 'r':
  85                         timeset = 1;
  86                         stime_file(optarg, tv);
  87                         break;
  88                 case 't':
  89                         timeset = 1;
  90                         stime_arg1(optarg, tv);
  91                         break;
  92                 default:
  93                         usage();
  94                 }
  95         argc -= optind;
  96         argv += optind;
  97
  98         /* Default is both -a and -m. */
  99         if (aflag == 0 && mflag == 0)
 100                 aflag = mflag = 1;
 101
 102         /*
 103          * If no -r or -t flag, at least two operands, the first of which
 104          * is an 8 or 10 digit number, use the obsolete time specification.
 105          */
 106         if (!timeset && argc > 1) {
 107                 strtol(argv[0], &p, 10);
 108                 len = p - argv[0];
 109                 if (*p == '\0' && (len == 8 || len == 10)) {
 110                         timeset = 1;
 111                         stime_arg2(*argv++, len == 10, tv);
 112                 }
 113         }
 114
 115         /* Otherwise use the current time of day. */
 116         if (!timeset)
 117                 tv[1] = tv[0];
 118
 119         if (*argv == NULL)
 120                 usage();
 121
 122         for (rval = 0; *argv; ++argv) {
 123                 /* See if the file exists. */
 124                 if (stat(*argv, &sb)) {
 125                         if (!cflag) {
 126                                 /* Create the file. */
 127                                 fd = open(*argv,
 128                                     O_WRONLY | O_CREAT, DEFFILEMODE);
 129                                 if (fd == -1 || fstat(fd, &sb) || close(fd)) {
 130                                         rval = 1;
 131                                         warn("%s", *argv);
 132                                         continue;
 133                                 }
 134
 135                                 /* If using the current time, we're done. */
 136                                 if (!timeset)
 137                                         continue;
 138                         } else
 139                                 continue;
 140                 }
 141
 142                 if (!aflag)
 143                         TIMESPEC_TO_TIMEVAL(&tv[0], &sb.st_atimespec);
 144                 if (!mflag)
 145                         TIMESPEC_TO_TIMEVAL(&tv[1], &sb.st_mtimespec);
 146
 147                 /* Try utimes(2). */
 148                 if (!utimes(*argv, tv))
 149                         continue;
 150
 151                 /* If the user specified a time, nothing else we can do. */
 152                 if (timeset) {
 153                         rval = 1;
 154                         warn("%s", *argv);
 155                 }
 156
 157                 /*
 158                  * System V and POSIX 1003.1 require that a NULL argument
 159                  * set the access/modification times to the current time.
 160                  * The permission checks are different, too, in that the
 161                  * ability to write the file is sufficient.  Take a shot.
 162                  */
 163                  if (!utimes(*argv, NULL))
 164                         continue;
 165
 166                 /* Try reading/writing. */
 167                 if (!S_ISLNK(sb.st_mode) && !S_ISDIR(sb.st_mode) &&
 168                     rw(*argv, &sb, fflag))
 169                         rval = 1;
 170                 else
 171                         warn("%s", *argv);
 172         }
 173         exit(rval);
 174 }
 175
 176 #define ATOI2(ar)       ((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
 177
 178 static void
 179 stime_arg1(const char *arg, struct timeval *tvp)
 180 {
 181         time_t now;
 182         struct tm *t;
 183         int yearset;
 184         char *p;
 185                                         /* Start with the current time. */
 186         now = tvp[0].tv_sec;
 187         if ((t = localtime(&now)) == NULL)
 188                 err(1, "localtime");
 189                                         /* [[CC]YY]MMDDhhmm[.SS] */
 190         if ((p = strchr(arg, '.')) == NULL) {
 191                 t->tm_sec = 0;          /* Seconds defaults to 0. */
 192         } else {
 193                 if (strlen(p + 1) != 2)
 194                         goto failed;
 195                 *p++ = '\0';
 196                 t->tm_sec = ATOI2(p);
 197         }
 198
 199         yearset = 0;
 200         switch(strlen(arg)) {
 201         case 12:                        /* CCYYMMDDhhmm */
 202                 t->tm_year = ATOI2(arg);
 203                 t->tm_year *= 100;
 204                 yearset = 1;
 205                 /* FALLTHROUGH */
 206         case 10:                        /* YYMMDDhhmm */
 207                 if (yearset) {
 208                         yearset = ATOI2(arg);
 209                         t->tm_year += yearset;
 210                 } else {
 211                         yearset = ATOI2(arg);
 212                         if (yearset < 69)
 213                                 t->tm_year = yearset + 2000;
 214                         else
 215                                 t->tm_year = yearset + 1900;
 216                 }
 217                 t->tm_year -= 1900;     /* Convert to UNIX time. */
 218                 /* FALLTHROUGH */
 219         case 8:                         /* MMDDhhmm */
 220                 t->tm_mon = ATOI2(arg);
 221                 --t->tm_mon;            /* Convert from 01-12 to 00-11 */
 222                 t->tm_mday = ATOI2(arg);
 223                 t->tm_hour = ATOI2(arg);
 224                 t->tm_min = ATOI2(arg);
 225                 break;
 226         default:
 227                 goto failed;
 228         }
 229
 230         t->tm_isdst = -1;               /* Figure out DST. */
 231         tvp[0].tv_sec = tvp[1].tv_sec = mktime(t);
 232         if (tvp[0].tv_sec == -1)
 233                 goto failed;
 234
 235         tvp[0].tv_usec = tvp[1].tv_usec = 0;
 236         return;
 237
 238 failed:
 239         errx(1, "out of range or illegal time "
 240                 "specification: [[CC]YY]MMDDhhmm[.SS]");
 241 }
 242
 243 static void
 244 stime_arg2(const char *arg, int year, struct timeval *tvp)
 245 {
 246         time_t now;
 247         struct tm *t;
 248                                         /* Start with the current time. */
 249         now = tvp[0].tv_sec;
 250         if ((t = localtime(&now)) == NULL)
 251                 err(1, "localtime");
 252
 253         t->tm_mon = ATOI2(arg);         /* MMDDhhmm[yy] */
 254         --t->tm_mon;                    /* Convert from 01-12 to 00-11 */
 255         t->tm_mday = ATOI2(arg);
 256         t->tm_hour = ATOI2(arg);
 257         t->tm_min = ATOI2(arg);
 258         if (year) {
 259                 t->tm_year = ATOI2(arg);
 260                 if (t->tm_year < 39)    /* support 2000-2038 not 1902-1969 */
 261                         t->tm_year += 100;
 262         }
 263
 264         t->tm_isdst = -1;               /* Figure out DST. */
 265         tvp[0].tv_sec = tvp[1].tv_sec = mktime(t);
 266         if (tvp[0].tv_sec == -1)
 267                 errx(1, "out of range or illegal time "
 268                         "specification: MMDDhhmm[yy]");
 269
 270         tvp[0].tv_usec = tvp[1].tv_usec = 0;
 271 }
 272
 273 static void
 274 stime_file(const char *fname, struct timeval *tvp)
 275 {
 276         struct stat sb;
 277
 278         if (stat(fname, &sb))
 279                 err(1, "%s", fname);
 280         TIMESPEC_TO_TIMEVAL(tvp, &sb.st_atimespec);
 281         TIMESPEC_TO_TIMEVAL(tvp + 1, &sb.st_mtimespec);
 282 }
 283
 284 static int
 285 rw(const char *fname, const struct stat *sbp, int force)
 286 {
 287         int fd, needed_chmod;
 288         const char *warn_msg = NULL;
 289         u_char byte;
 290
 291         /* Try regular files. */
 292         if (!S_ISREG(sbp->st_mode)) {
 293                 warnx("%s: %s", fname, strerror(EFTYPE));
 294                 return (1);
 295         }
 296
 297         needed_chmod = 0;
 298         if ((fd = open(fname, O_RDWR, 0)) == -1) {
 299                 if (!force || chmod(fname, DEFFILEMODE))
 300                         goto failed;
 301                 if ((fd = open(fname, O_RDWR, 0)) == -1)
 302                         goto failed;
 303                 needed_chmod = 1;
 304         }
 305
 306         if (sbp->st_size != 0) {
 307                 if (read(fd, &byte, sizeof(byte)) != sizeof(byte))
 308                         goto failed;
 309                 if (lseek(fd, (off_t)0, SEEK_SET) == -1)
 310                         goto failed;
 311                 if (write(fd, &byte, sizeof(byte)) != sizeof(byte))
 312                         goto failed;
 313         } else {
 314                 if (write(fd, &byte, sizeof(byte)) != sizeof(byte))
 315                         goto failed;
 316                 if (ftruncate(fd, (off_t)0)) {
 317                         warn_msg = "%s: file modified";
 318                         goto failed;
 319                 }
 320         }
 321
 322         if (close(fd))
 323                 goto failed;
 324         if (needed_chmod && chmod(fname, sbp->st_mode)) {
 325                 warn_msg = "%s: permissions modified";
 326                 goto failed;
 327         }
 328         return(0);
 329
 330 failed:
 331         if (warn_msg != NULL)
 332                 warnx(warn_msg, fname);
 333         else
 334                 warn("%s", fname);
 335         return(1);
 336 }
 337
 338 static void
 339 usage(void)
 340 {
 341         fprintf(stderr, "usage: touch [-acfm] [-r file] "
 342                         "[-t [[CC]YY]MMDDhhmm[.SS]] file ...\n");
 343         exit(1);
 344 }