bin/cp/utils.c

   1 /*-
   2  * Copyright (c) 1991, 1993, 1994
   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  * @(#)utils.c  8.3 (Berkeley) 4/1/94
  34  * $FreeBSD: src/bin/cp/utils.c,v 1.45 2005/02/09 17:37:37 ru Exp $
  35  * $DragonFly: src/bin/cp/utils.c,v 1.12 2008/09/05 03:16:55 y0netan1 Exp $
  36  */
  37
  38 #include <sys/param.h>
  39 #include <sys/stat.h>
  40 #include <sys/time.h>
  41 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
  42 #include <sys/mman.h>
  43 #endif
  44
  45 #include <err.h>
  46 #include <errno.h>
  47 #include <fcntl.h>
  48 #include <fts.h>
  49 #include <limits.h>
  50 #include <stdio.h>
  51 #include <stdlib.h>
  52 #include <sysexits.h>
  53 #include <unistd.h>
  54
  55 #include "extern.h"
  56 #define cp_pct(x,y)     (int)(100.0 * (double)(x) / (double)(y))
  57
  58 #define YESNO "(y/n [n]) "
  59
  60 int
  61 copy_file(const FTSENT *entp, int dne)
  62 {
  63         static char buf[MAXBSIZE];
  64         struct stat *fs;
  65         int ch, checkch, from_fd, rval, to_fd;
  66         size_t rcount, wcount, wresid;
  67         off_t wtotal;
  68         char *bufp;
  69 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
  70         char *p;
  71 #endif
  72
  73         if ((from_fd = open(entp->fts_path, O_RDONLY, 0)) == -1) {
  74                 warn("%s", entp->fts_path);
  75                 return (1);
  76         }
  77
  78         fs = entp->fts_statp;
  79
  80         /*
  81          * If the file exists and we're interactive, verify with the user.
  82          * If the file DNE, set the mode to be the from file, minus setuid
  83          * bits, modified by the umask; arguably wrong, but it makes copying
  84          * executables work right and it's been that way forever.  (The
  85          * other choice is 666 or'ed with the execute bits on the from file
  86          * modified by the umask.)
  87          */
  88         if (!dne) {
  89                 if (nflag) {
  90                         if (vflag)
  91                                 printf("%s not overwritten\n", to.p_path);
  92                         close(from_fd);
  93                         return (0);
  94                 } else if (iflag) {
  95                         fprintf(stderr, "overwrite %s? %s",
  96                                         to.p_path, YESNO);
  97                         checkch = ch = getchar();
  98                         while (ch != '\n' && ch != EOF)
  99                                 ch = getchar();
 100                         if (checkch != 'y' && checkch != 'Y') {
 101                                 close(from_fd);
 102                                 fprintf(stderr, "not overwritten\n");
 103                                 return (1);
 104                         }
 105                 }
 106
 107                 if (fflag) {
 108                     /* remove existing destination file name,
 109                      * create a new file  */
 110                     unlink(to.p_path);
 111                     to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
 112                                  fs->st_mode & ~(S_ISUID | S_ISGID));
 113                 } else
 114                     /* overwrite existing destination file name */
 115                     to_fd = open(to.p_path, O_WRONLY | O_TRUNC, 0);
 116         } else
 117                 to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
 118                     fs->st_mode & ~(S_ISUID | S_ISGID));
 119
 120         if (to_fd == -1) {
 121                 warn("%s", to.p_path);
 122                 close(from_fd);
 123                 return (1);
 124         }
 125
 126         rval = 0;
 127
 128         /*
 129          * Mmap and write if less than 8M (the limit is so we don't totally
 130          * trash memory on big files.  This is really a minor hack, but it
 131          * wins some CPU back.
 132          */
 133 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
 134         if (S_ISREG(fs->st_mode) && fs->st_size > 0 &&
 135             fs->st_size <= 8 * 1048576) {
 136                 if ((p = mmap(NULL, (size_t)fs->st_size, PROT_READ,
 137                     MAP_SHARED, from_fd, (off_t)0)) == MAP_FAILED) {
 138                         warn("%s", entp->fts_path);
 139                         rval = 1;
 140                 } else {
 141                         wtotal = 0;
 142                         for (bufp = p, wresid = fs->st_size; ;
 143                             bufp += wcount, wresid -= wcount) {
 144                                 wcount = write(to_fd, bufp, wresid);
 145                                 if ((ssize_t)wcount == -1)
 146                                         break;
 147                                 wtotal += wcount;
 148                                 if (info) {
 149                                         info = 0;
 150                                         fprintf(stderr,
 151                                             "%s -> %s %3d%%\n",
 152                                             entp->fts_path, to.p_path,
 153                                             cp_pct(wtotal, fs->st_size));
 154                                 }
 155                                 if (wcount >= wresid || wcount == 0)
 156                                         break;
 157                         }
 158                         if (wcount != wresid) {
 159                                 warn("%s", to.p_path);
 160                                 rval = 1;
 161                         }
 162                         /* Some systems don't unmap on close(2). */
 163                         if (munmap(p, fs->st_size) < 0) {
 164                                 warn("%s", entp->fts_path);
 165                                 rval = 1;
 166                         }
 167                 }
 168         } else
 169 #endif
 170         {
 171                 wtotal = 0;
 172                 while ((ssize_t)(rcount = read(from_fd, buf, MAXBSIZE)) > 0) {
 173                         for (bufp = buf, wresid = rcount; ;
 174                             bufp += wcount, wresid -= wcount) {
 175                                 wcount = write(to_fd, bufp, wresid);
 176                                 if ((ssize_t)wcount == -1)
 177                                         break;
 178                                 wtotal += wcount;
 179                                 if (info) {
 180                                         info = 0;
 181                                         fprintf(stderr,
 182                                             "%s -> %s %3d%%\n",
 183                                             entp->fts_path, to.p_path,
 184                                             cp_pct(wtotal, fs->st_size));
 185                                 }
 186                                 if (wcount >= wresid || wcount == 0)
 187                                         break;
 188                         }
 189                         if (wcount != wresid) {
 190                                 warn("%s", to.p_path);
 191                                 rval = 1;
 192                                 break;
 193                         }
 194                 }
 195                 if ((ssize_t)rcount == -1) {
 196                         warn("%s", entp->fts_path);
 197                         rval = 1;
 198                 }
 199         }
 200
 201         /*
 202          * Don't remove the target even after an error.  The target might
 203          * not be a regular file, or its attributes might be important,
 204          * or its contents might be irreplaceable.  It would only be safe
 205          * to remove it if we created it and its length is 0.
 206          */
 207
 208         if (pflag && setfile(fs, to_fd))
 209                 rval = 1;
 210         close(from_fd);
 211         if (close(to_fd)) {
 212                 warn("%s", to.p_path);
 213                 rval = 1;
 214         }
 215         return (rval);
 216 }
 217
 218 int
 219 copy_link(const FTSENT *p, int exists)
 220 {
 221         int len;
 222         char linkname[PATH_MAX];
 223
 224         if ((len = readlink(p->fts_path, linkname, sizeof(linkname) - 1)) == -1) {
 225                 warn("readlink: %s", p->fts_path);
 226                 return (1);
 227         }
 228         linkname[len] = '\0';
 229         if (exists && unlink(to.p_path)) {
 230                 warn("unlink: %s", to.p_path);
 231                 return (1);
 232         }
 233         if (symlink(linkname, to.p_path)) {
 234                 warn("symlink: %s", linkname);
 235                 return (1);
 236         }
 237         return (pflag ? setfile(p->fts_statp, -1) : 0);
 238 }
 239
 240 int
 241 copy_fifo(struct stat *from_stat, int exists)
 242 {
 243         if (exists && unlink(to.p_path)) {
 244                 warn("unlink: %s", to.p_path);
 245                 return (1);
 246         }
 247         if (mkfifo(to.p_path, from_stat->st_mode)) {
 248                 warn("mkfifo: %s", to.p_path);
 249                 return (1);
 250         }
 251         return (pflag ? setfile(from_stat, -1) : 0);
 252 }
 253
 254 int
 255 copy_special(struct stat *from_stat, int exists)
 256 {
 257         if (exists && unlink(to.p_path)) {
 258                 warn("unlink: %s", to.p_path);
 259                 return (1);
 260         }
 261         if (mknod(to.p_path, from_stat->st_mode, from_stat->st_rdev)) {
 262                 warn("mknod: %s", to.p_path);
 263                 return (1);
 264         }
 265         return (pflag ? setfile(from_stat, -1) : 0);
 266 }
 267
 268 int
 269 setfile(struct stat *fs, int fd)
 270 {
 271         static struct timeval tv[2];
 272         struct stat ts;
 273         int rval, gotstat, islink, fdval;
 274
 275         rval = 0;
 276         fdval = fd != -1;
 277         islink = !fdval && S_ISLNK(fs->st_mode);
 278         fs->st_mode &= S_ISUID | S_ISGID | S_ISVTX |
 279                        S_IRWXU | S_IRWXG | S_IRWXO;
 280
 281         TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
 282         TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
 283         if (islink ? lutimes(to.p_path, tv) : utimes(to.p_path, tv)) {
 284                 warn("%sutimes: %s", islink ? "l" : "", to.p_path);
 285                 rval = 1;
 286         }
 287         if (fdval ? fstat(fd, &ts) :
 288             (islink ? lstat(to.p_path, &ts) : stat(to.p_path, &ts))) {
 289                 gotstat = 0;
 290         } else {
 291                 gotstat = 1;
 292                 ts.st_mode &= S_ISUID | S_ISGID | S_ISVTX |
 293                               S_IRWXU | S_IRWXG | S_IRWXO;
 294         }
 295         /*
 296          * Changing the ownership probably won't succeed, unless we're root
 297          * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
 298          * the mode; current BSD behavior is to remove all setuid bits on
 299          * chown.  If chown fails, lose setuid/setgid bits.
 300          */
 301         if (!gotstat || fs->st_uid != ts.st_uid || fs->st_gid != ts.st_gid)
 302                 if (fdval ? fchown(fd, fs->st_uid, fs->st_gid) :
 303                     (islink ? lchown(to.p_path, fs->st_uid, fs->st_gid) :
 304                     chown(to.p_path, fs->st_uid, fs->st_gid))) {
 305                         if (errno != EPERM) {
 306                                 warn("chown: %s", to.p_path);
 307                                 rval = 1;
 308                         }
 309                         fs->st_mode &= ~(S_ISUID | S_ISGID);
 310                 }
 311
 312         if (!gotstat || fs->st_mode != ts.st_mode)
 313                 if (fdval ? fchmod(fd, fs->st_mode) :
 314                     (islink ? lchmod(to.p_path, fs->st_mode) :
 315                     chmod(to.p_path, fs->st_mode))) {
 316                         warn("chmod: %s", to.p_path);
 317                         rval = 1;
 318                 }
 319
 320         if (!gotstat || fs->st_flags != ts.st_flags)
 321                 if (fdval ?
 322                     fchflags(fd, fs->st_flags) :
 323                     (islink ? (errno = 0) :
 324                     chflags(to.p_path, fs->st_flags))) {
 325                         warn("chflags: %s", to.p_path);
 326                         rval = 1;
 327                 }
 328
 329         return (rval);
 330 }
 331
 332 void
 333 usage(void)
 334 {
 335         fprintf(stderr, "%s\n%s\n",
 336 "usage: cp [-R [-H | -L | -P]] [-f | -i | -n] [-pv] source_file target_file",
 337 "       cp [-R [-H | -L | -P]] [-f | -i | -n] [-pv] source_file ... "
 338 "target_directory");
 339         exit(EX_USAGE);
 340 }