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 1.9 2006/08/03 16:40:45 swildner 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, rcount, rval, to_fd, wcount, wresid, wtotal;
  66         char *bufp;
  67 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
  68         char *p;
  69 #endif
  70
  71         if ((from_fd = open(entp->fts_path, O_RDONLY, 0)) == -1) {
  72                 warn("%s", entp->fts_path);
  73                 return (1);
  74         }
  75
  76         fs = entp->fts_statp;
  77
  78         /*
  79          * If the file exists and we're interactive, verify with the user.
  80          * If the file DNE, set the mode to be the from file, minus setuid
  81          * bits, modified by the umask; arguably wrong, but it makes copying
  82          * executables work right and it's been that way forever.  (The
  83          * other choice is 666 or'ed with the execute bits on the from file
  84          * modified by the umask.)
  85          */
  86         if (!dne) {
  87                 if (nflag) {
  88                         if (vflag)
  89                                 printf("%s not overwritten\n", to.p_path);
  90                         close(from_fd);
  91                         return (0);
  92                 } else if (iflag) {
  93                         fprintf(stderr, "overwrite %s? %s",
  94                                         to.p_path, YESNO);
  95                         checkch = ch = getchar();
  96                         while (ch != '\n' && ch != EOF)
  97                                 ch = getchar();
  98                         if (checkch != 'y' && checkch != 'Y') {
  99                                 close(from_fd);
 100                                 fprintf(stderr, "not overwritten\n");
 101                                 return (1);
 102                         }
 103                 }
 104
 105                 if (fflag) {
 106                     /* remove existing destination file name,
 107                      * create a new file  */
 108                     unlink(to.p_path);
 109                     to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
 110                                  fs->st_mode & ~(S_ISUID | S_ISGID));
 111                 } else
 112                     /* overwrite existing destination file name */
 113                     to_fd = open(to.p_path, O_WRONLY | O_TRUNC, 0);
 114         } else
 115                 to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
 116                     fs->st_mode & ~(S_ISUID | S_ISGID));
 117
 118         if (to_fd == -1) {
 119                 warn("%s", to.p_path);
 120                 close(from_fd);
 121                 return (1);
 122         }
 123
 124         rval = 0;
 125
 126         /*
 127          * Mmap and write if less than 8M (the limit is so we don't totally
 128          * trash memory on big files.  This is really a minor hack, but it
 129          * wins some CPU back.
 130          */
 131 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
 132         if (S_ISREG(fs->st_mode) && fs->st_size > 0 &&
 133             fs->st_size <= 8 * 1048576) {
 134                 if ((p = mmap(NULL, (size_t)fs->st_size, PROT_READ,
 135                     MAP_SHARED, from_fd, (off_t)0)) == MAP_FAILED) {
 136                         warn("%s", entp->fts_path);
 137                         rval = 1;
 138                 } else {
 139                         wtotal = 0;
 140                         for (bufp = p, wresid = fs->st_size; ;
 141                             bufp += wcount, wresid -= wcount) {
 142                                 wcount = write(to_fd, bufp, wresid);
 143                                 wtotal += wcount;
 144                                 if (info) {
 145                                         info = 0;
 146                                         fprintf(stderr,
 147                                             "%s -> %s %3d%%\n",
 148                                             entp->fts_path, to.p_path,
 149                                             cp_pct(wtotal, fs->st_size));
 150                                 }
 151                                 if (wcount >= wresid || wcount <= 0)
 152                                         break;
 153                         }
 154                         if (wcount != wresid) {
 155                                 warn("%s", to.p_path);
 156                                 rval = 1;
 157                         }
 158                         /* Some systems don't unmap on close(2). */
 159                         if (munmap(p, fs->st_size) < 0) {
 160                                 warn("%s", entp->fts_path);
 161                                 rval = 1;
 162                         }
 163                 }
 164         } else
 165 #endif
 166         {
 167                 wtotal = 0;
 168                 while ((rcount = read(from_fd, buf, MAXBSIZE)) > 0) {
 169                         for (bufp = buf, wresid = rcount; ;
 170                             bufp += wcount, wresid -= wcount) {
 171                                 wcount = write(to_fd, bufp, wresid);
 172                                 wtotal += wcount;
 173                                 if (info) {
 174                                         info = 0;
 175                                         fprintf(stderr,
 176                                             "%s -> %s %3d%%\n",
 177                                             entp->fts_path, to.p_path,
 178                                             cp_pct(wtotal, fs->st_size));
 179                                 }
 180                                 if (wcount >= wresid || wcount <= 0)
 181                                         break;
 182                         }
 183                         if (wcount != wresid) {
 184                                 warn("%s", to.p_path);
 185                                 rval = 1;
 186                                 break;
 187                         }
 188                 }
 189                 if (rcount < 0) {
 190                         warn("%s", entp->fts_path);
 191                         rval = 1;
 192                 }
 193         }
 194
 195         /*
 196          * Don't remove the target even after an error.  The target might
 197          * not be a regular file, or its attributes might be important,
 198          * or its contents might be irreplaceable.  It would only be safe
 199          * to remove it if we created it and its length is 0.
 200          */
 201
 202         if (pflag && setfile(fs, to_fd))
 203                 rval = 1;
 204         close(from_fd);
 205         if (close(to_fd)) {
 206                 warn("%s", to.p_path);
 207                 rval = 1;
 208         }
 209         return (rval);
 210 }
 211
 212 int
 213 copy_link(const FTSENT *p, int exists)
 214 {
 215         int len;
 216         char linkname[PATH_MAX];
 217
 218         if ((len = readlink(p->fts_path, linkname, sizeof(linkname) - 1)) == -1) {
 219                 warn("readlink: %s", p->fts_path);
 220                 return (1);
 221         }
 222         linkname[len] = '\0';
 223         if (exists && unlink(to.p_path)) {
 224                 warn("unlink: %s", to.p_path);
 225                 return (1);
 226         }
 227         if (symlink(linkname, to.p_path)) {
 228                 warn("symlink: %s", linkname);
 229                 return (1);
 230         }
 231         return (pflag ? setfile(p->fts_statp, -1) : 0);
 232 }
 233
 234 int
 235 copy_fifo(struct stat *from_stat, int exists)
 236 {
 237         if (exists && unlink(to.p_path)) {
 238                 warn("unlink: %s", to.p_path);
 239                 return (1);
 240         }
 241         if (mkfifo(to.p_path, from_stat->st_mode)) {
 242                 warn("mkfifo: %s", to.p_path);
 243                 return (1);
 244         }
 245         return (pflag ? setfile(from_stat, -1) : 0);
 246 }
 247
 248 int
 249 copy_special(struct stat *from_stat, int exists)
 250 {
 251         if (exists && unlink(to.p_path)) {
 252                 warn("unlink: %s", to.p_path);
 253                 return (1);
 254         }
 255         if (mknod(to.p_path, from_stat->st_mode, from_stat->st_rdev)) {
 256                 warn("mknod: %s", to.p_path);
 257                 return (1);
 258         }
 259         return (pflag ? setfile(from_stat, -1) : 0);
 260 }
 261
 262 int
 263 setfile(struct stat *fs, int fd)
 264 {
 265         static struct timeval tv[2];
 266         struct stat ts;
 267         int rval, gotstat, islink, fdval;
 268
 269         rval = 0;
 270         fdval = fd != -1;
 271         islink = !fdval && S_ISLNK(fs->st_mode);
 272         fs->st_mode &= S_ISUID | S_ISGID | S_ISVTX |
 273                        S_IRWXU | S_IRWXG | S_IRWXO;
 274
 275         TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
 276         TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
 277         if (islink ? lutimes(to.p_path, tv) : utimes(to.p_path, tv)) {
 278                 warn("%sutimes: %s", islink ? "l" : "", to.p_path);
 279                 rval = 1;
 280         }
 281         if (fdval ? fstat(fd, &ts) :
 282             (islink ? lstat(to.p_path, &ts) : stat(to.p_path, &ts))) {
 283                 gotstat = 0;
 284         } else {
 285                 gotstat = 1;
 286                 ts.st_mode &= S_ISUID | S_ISGID | S_ISVTX |
 287                               S_IRWXU | S_IRWXG | S_IRWXO;
 288         }
 289         /*
 290          * Changing the ownership probably won't succeed, unless we're root
 291          * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
 292          * the mode; current BSD behavior is to remove all setuid bits on
 293          * chown.  If chown fails, lose setuid/setgid bits.
 294          */
 295         if (!gotstat || fs->st_uid != ts.st_uid || fs->st_gid != ts.st_gid)
 296                 if (fdval ? fchown(fd, fs->st_uid, fs->st_gid) :
 297                     (islink ? lchown(to.p_path, fs->st_uid, fs->st_gid) :
 298                     chown(to.p_path, fs->st_uid, fs->st_gid))) {
 299                         if (errno != EPERM) {
 300                                 warn("chown: %s", to.p_path);
 301                                 rval = 1;
 302                         }
 303                         fs->st_mode &= ~(S_ISUID | S_ISGID);
 304                 }
 305
 306         if (!gotstat || fs->st_mode != ts.st_mode)
 307                 if (fdval ? fchmod(fd, fs->st_mode) :
 308                     (islink ? lchmod(to.p_path, fs->st_mode) :
 309                     chmod(to.p_path, fs->st_mode))) {
 310                         warn("chmod: %s", to.p_path);
 311                         rval = 1;
 312                 }
 313
 314         if (!gotstat || fs->st_flags != ts.st_flags)
 315                 if (fdval ?
 316                     fchflags(fd, fs->st_flags) :
 317                     (islink ? (errno = ENOSYS) :
 318                     chflags(to.p_path, fs->st_flags))) {
 319                         warn("chflags: %s", to.p_path);
 320                         rval = 1;
 321                 }
 322
 323         return (rval);
 324 }
 325
 326 void
 327 usage(void)
 328 {
 329         fprintf(stderr, "%s\n%s\n",
 330 "usage: cp [-R [-H | -L | -P]] [-f | -i | -n] [-pv] source_file target_file",
 331 "       cp [-R [-H | -L | -P]] [-f | -i | -n] [-pv] source_file ... "
 332 "target_directory");
 333         exit(EX_USAGE);
 334 }