Home | History | Annotate | Download | only in cp
      1 /* $NetBSD: utils.c,v 1.42 2013/12/11 06:00:11 dholland Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 1991, 1993, 1994
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 #ifndef lint
     34 #if 0
     35 static char sccsid[] = "@(#)utils.c	8.3 (Berkeley) 4/1/94";
     36 #else
     37 __RCSID("$NetBSD: utils.c,v 1.42 2013/12/11 06:00:11 dholland Exp $");
     38 #endif
     39 #endif /* not lint */
     40 
     41 #include <sys/mman.h>
     42 #include <sys/param.h>
     43 #include <sys/stat.h>
     44 #include <sys/time.h>
     45 #include <sys/extattr.h>
     46 
     47 #include <err.h>
     48 #include <errno.h>
     49 #include <fcntl.h>
     50 #include <fts.h>
     51 #include <stdbool.h>
     52 #include <stdio.h>
     53 #include <stdlib.h>
     54 #include <string.h>
     55 #include <unistd.h>
     56 
     57 #include "extern.h"
     58 
     59 #define	MMAP_MAX_SIZE	(8 * 1048576)
     60 #define	MMAP_MAX_WRITE	(64 * 1024)
     61 
     62 int
     63 set_utimes(const char *file, struct stat *fs)
     64 {
     65     static struct timeval tv[2];
     66 
     67 #ifdef __ANDROID__
     68     tv[0].tv_sec = fs->st_atime;
     69     tv[0].tv_usec = 0;
     70     tv[1].tv_sec = fs->st_mtime;
     71     tv[1].tv_usec = 0;
     72 
     73     if (utimes(file, tv)) {
     74         warn("utimes: %s", file);
     75         return 1;
     76     }
     77 #else
     78     TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
     79     TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
     80 
     81     if (lutimes(file, tv)) {
     82 	warn("lutimes: %s", file);
     83 	return (1);
     84     }
     85 #endif
     86     return (0);
     87 }
     88 
     89 struct finfo {
     90 	const char *from;
     91 	const char *to;
     92 	size_t size;
     93 };
     94 
     95 static void
     96 progress(const struct finfo *fi, size_t written)
     97 {
     98 	int pcent = (int)((100.0 * written) / fi->size);
     99 
    100 	pinfo = 0;
    101 	(void)fprintf(stderr, "%s => %s %zu/%zu bytes %d%% written\n",
    102 	    fi->from, fi->to, written, fi->size, pcent);
    103 }
    104 
    105 int
    106 copy_file(FTSENT *entp, int dne)
    107 {
    108 	static char buf[MAXBSIZE];
    109 	struct stat to_stat, *fs;
    110 	int ch, checkch, from_fd, rcount, rval, to_fd, tolnk, wcount;
    111 	char *p;
    112 	size_t ptotal = 0;
    113 
    114 	if ((from_fd = open(entp->fts_path, O_RDONLY, 0)) == -1) {
    115 		warn("%s", entp->fts_path);
    116 		return (1);
    117 	}
    118 
    119 	to_fd = -1;
    120 	fs = entp->fts_statp;
    121 	tolnk = ((Rflag && !(Lflag || Hflag)) || Pflag);
    122 
    123 	/*
    124 	 * If the file exists and we're interactive, verify with the user.
    125 	 * If the file DNE, set the mode to be the from file, minus setuid
    126 	 * bits, modified by the umask; arguably wrong, but it makes copying
    127 	 * executables work right and it's been that way forever.  (The
    128 	 * other choice is 666 or'ed with the execute bits on the from file
    129 	 * modified by the umask.)
    130 	 */
    131 	if (!dne) {
    132 		struct stat sb;
    133 		int sval;
    134 
    135 		if (iflag) {
    136 			(void)fprintf(stderr, "overwrite %s? ", to.p_path);
    137 			checkch = ch = getchar();
    138 			while (ch != '\n' && ch != EOF)
    139 				ch = getchar();
    140 			if (checkch != 'y' && checkch != 'Y') {
    141 				(void)close(from_fd);
    142 				return (0);
    143 			}
    144 		}
    145 
    146 		sval = tolnk ?
    147 			lstat(to.p_path, &sb) : stat(to.p_path, &sb);
    148 		if (sval == -1) {
    149 			warn("stat: %s", to.p_path);
    150 			(void)close(from_fd);
    151 			return (1);
    152 		}
    153 
    154 		if (!(tolnk && S_ISLNK(sb.st_mode)))
    155 			to_fd = open(to.p_path, O_WRONLY | O_TRUNC, 0);
    156 	} else
    157 		to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
    158 		    fs->st_mode & ~(S_ISUID | S_ISGID));
    159 
    160 	if (to_fd == -1 && (fflag || tolnk)) {
    161 		/*
    162 		 * attempt to remove existing destination file name and
    163 		 * create a new file
    164 		 */
    165 		(void)unlink(to.p_path);
    166 		to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
    167 			     fs->st_mode & ~(S_ISUID | S_ISGID));
    168 	}
    169 
    170 	if (to_fd == -1) {
    171 		warn("%s", to.p_path);
    172 		(void)close(from_fd);
    173 		return (1);
    174 	}
    175 
    176 	rval = 0;
    177 
    178 	/* if hard linking then simply close the open fds, link and return */
    179 	if (lflag) {
    180 		(void)close(from_fd);
    181 		(void)close(to_fd);
    182 		(void)unlink(to.p_path);
    183 		if (link(entp->fts_path, to.p_path)) {
    184 			warn("%s", to.p_path);
    185 			return (1);
    186 		}
    187 		return (0);
    188 	}
    189 
    190 	/*
    191 	 * There's no reason to do anything other than close the file
    192 	 * now if it's empty, so let's not bother.
    193 	 */
    194 #ifndef __ANDROID__ // Files in /proc report length 0. mmap will fail but we'll fall back to read.
    195 	if (fs->st_size > 0) {
    196 #endif
    197 		struct finfo fi;
    198 
    199 		fi.from = entp->fts_path;
    200 		fi.to = to.p_path;
    201 		fi.size = (size_t)fs->st_size;
    202 
    203 		/*
    204 		 * Mmap and write if less than 8M (the limit is so
    205 		 * we don't totally trash memory on big files).
    206 		 * This is really a minor hack, but it wins some CPU back.
    207 		 */
    208 		bool use_read;
    209 
    210 		use_read = true;
    211 		if (fs->st_size <= MMAP_MAX_SIZE) {
    212 			size_t fsize = (size_t)fs->st_size;
    213 			p = mmap(NULL, fsize, PROT_READ, MAP_FILE|MAP_SHARED,
    214 			    from_fd, (off_t)0);
    215 			if (p != MAP_FAILED) {
    216 				size_t remainder;
    217 
    218 				use_read = false;
    219 
    220 				(void) madvise(p, (size_t)fs->st_size,
    221 				     MADV_SEQUENTIAL);
    222 
    223 				/*
    224 				 * Write out the data in small chunks to
    225 				 * avoid locking the output file for a
    226 				 * long time if the reading the data from
    227 				 * the source is slow.
    228 				 */
    229 				remainder = fsize;
    230 				do {
    231 					ssize_t chunk;
    232 
    233 					chunk = (remainder > MMAP_MAX_WRITE) ?
    234 					    MMAP_MAX_WRITE : remainder;
    235 					if (write(to_fd, &p[fsize - remainder],
    236 					    chunk) != chunk) {
    237 						warn("%s", to.p_path);
    238 						rval = 1;
    239 						break;
    240 					}
    241 					remainder -= chunk;
    242 					ptotal += chunk;
    243 					if (pinfo)
    244 						progress(&fi, ptotal);
    245 				} while (remainder > 0);
    246 
    247 				if (munmap(p, fsize) < 0) {
    248 					warn("%s", entp->fts_path);
    249 					rval = 1;
    250 				}
    251 			}
    252 		}
    253 
    254 		if (use_read) {
    255 			while ((rcount = read(from_fd, buf, MAXBSIZE)) > 0) {
    256 				wcount = write(to_fd, buf, (size_t)rcount);
    257 				if (rcount != wcount || wcount == -1) {
    258 					warn("%s", to.p_path);
    259 					rval = 1;
    260 					break;
    261 				}
    262 				ptotal += wcount;
    263 				if (pinfo)
    264 					progress(&fi, ptotal);
    265 			}
    266 			if (rcount < 0) {
    267 				warn("%s", entp->fts_path);
    268 				rval = 1;
    269 			}
    270 		}
    271 #ifndef __ANDROID__
    272 	}
    273 #endif
    274 
    275 #ifndef __ANDROID__
    276 	if (pflag && (fcpxattr(from_fd, to_fd) != 0))
    277 		warn("%s: error copying extended attributes", to.p_path);
    278 #endif
    279 
    280 	(void)close(from_fd);
    281 
    282 	if (rval == 1) {
    283 		(void)close(to_fd);
    284 		return (1);
    285 	}
    286 
    287 	if (pflag && setfile(fs, to_fd))
    288 		rval = 1;
    289 	/*
    290 	 * If the source was setuid or setgid, lose the bits unless the
    291 	 * copy is owned by the same user and group.
    292 	 */
    293 #define	RETAINBITS \
    294 	(S_ISUID | S_ISGID | S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO)
    295 	if (!pflag && dne
    296 	    && fs->st_mode & (S_ISUID | S_ISGID) && fs->st_uid == myuid) {
    297 		if (fstat(to_fd, &to_stat)) {
    298 			warn("%s", to.p_path);
    299 			rval = 1;
    300 		} else if (fs->st_gid == to_stat.st_gid &&
    301 		    fchmod(to_fd, fs->st_mode & RETAINBITS & ~myumask)) {
    302 			warn("%s", to.p_path);
    303 			rval = 1;
    304 		}
    305 	}
    306 	if (close(to_fd)) {
    307 		warn("%s", to.p_path);
    308 		rval = 1;
    309 	}
    310 	/* set the mod/access times now after close of the fd */
    311 	if (pflag && set_utimes(to.p_path, fs)) {
    312 	    rval = 1;
    313 	}
    314 	return (rval);
    315 }
    316 
    317 int
    318 copy_link(FTSENT *p, int exists)
    319 {
    320 	int len;
    321 	char target[MAXPATHLEN];
    322 
    323 	if ((len = readlink(p->fts_path, target, sizeof(target)-1)) == -1) {
    324 		warn("readlink: %s", p->fts_path);
    325 		return (1);
    326 	}
    327 	target[len] = '\0';
    328 	if (exists && unlink(to.p_path)) {
    329 		warn("unlink: %s", to.p_path);
    330 		return (1);
    331 	}
    332 	if (symlink(target, to.p_path)) {
    333 		warn("symlink: %s", target);
    334 		return (1);
    335 	}
    336 	return (pflag ? setfile(p->fts_statp, 0) : 0);
    337 }
    338 
    339 int
    340 copy_fifo(struct stat *from_stat, int exists)
    341 {
    342 	if (exists && unlink(to.p_path)) {
    343 		warn("unlink: %s", to.p_path);
    344 		return (1);
    345 	}
    346 	if (mkfifo(to.p_path, from_stat->st_mode)) {
    347 		warn("mkfifo: %s", to.p_path);
    348 		return (1);
    349 	}
    350 	return (pflag ? setfile(from_stat, 0) : 0);
    351 }
    352 
    353 int
    354 copy_special(struct stat *from_stat, int exists)
    355 {
    356 	if (exists && unlink(to.p_path)) {
    357 		warn("unlink: %s", to.p_path);
    358 		return (1);
    359 	}
    360 	if (mknod(to.p_path, from_stat->st_mode, from_stat->st_rdev)) {
    361 		warn("mknod: %s", to.p_path);
    362 		return (1);
    363 	}
    364 	return (pflag ? setfile(from_stat, 0) : 0);
    365 }
    366 
    367 
    368 /*
    369  * Function: setfile
    370  *
    371  * Purpose:
    372  *   Set the owner/group/permissions for the "to" file to the information
    373  *   in the stat structure.  If fd is zero, also call set_utimes() to set
    374  *   the mod/access times.  If fd is non-zero, the caller must do a utimes
    375  *   itself after close(fd).
    376  */
    377 int
    378 setfile(struct stat *fs, int fd)
    379 {
    380 	int rval, islink;
    381 
    382 	rval = 0;
    383 	islink = S_ISLNK(fs->st_mode);
    384 	fs->st_mode &= S_ISUID | S_ISGID | S_IRWXU | S_IRWXG | S_IRWXO;
    385 
    386 	/*
    387 	 * Changing the ownership probably won't succeed, unless we're root
    388 	 * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
    389 	 * the mode; current BSD behavior is to remove all setuid bits on
    390 	 * chown.  If chown fails, lose setuid/setgid bits.
    391 	 */
    392 	if (fd ? fchown(fd, fs->st_uid, fs->st_gid) :
    393 	    lchown(to.p_path, fs->st_uid, fs->st_gid)) {
    394 		if (errno != EPERM) {
    395 			warn("chown: %s", to.p_path);
    396 			rval = 1;
    397 		}
    398 		fs->st_mode &= ~(S_ISUID | S_ISGID);
    399 	}
    400 #ifdef __ANDROID__
    401 	if (fd ? fchmod(fd, fs->st_mode) : chmod(to.p_path, fs->st_mode)) {
    402 #else
    403 	if (fd ? fchmod(fd, fs->st_mode) : lchmod(to.p_path, fs->st_mode)) {
    404 #endif
    405 		warn("chmod: %s", to.p_path);
    406 		rval = 1;
    407 	}
    408 
    409 #ifndef __ANDROID__
    410 	if (!islink && !Nflag) {
    411 		unsigned long fflags = fs->st_flags;
    412 		/*
    413 		 * XXX
    414 		 * NFS doesn't support chflags; ignore errors unless
    415 		 * there's reason to believe we're losing bits.
    416 		 * (Note, this still won't be right if the server
    417 		 * supports flags and we were trying to *remove* flags
    418 		 * on a file that we copied, i.e., that we didn't create.)
    419 		 */
    420 		errno = 0;
    421 		if ((fd ? fchflags(fd, fflags) :
    422 		    chflags(to.p_path, fflags)) == -1)
    423 			if (errno != EOPNOTSUPP || fs->st_flags != 0) {
    424 				warn("chflags: %s", to.p_path);
    425 				rval = 1;
    426 			}
    427 	}
    428 #endif
    429 	/* if fd is non-zero, caller must call set_utimes() after close() */
    430 	if (fd == 0 && set_utimes(to.p_path, fs))
    431 	    rval = 1;
    432 	return (rval);
    433 }
    434 
    435 void
    436 usage(void)
    437 {
    438 	(void)fprintf(stderr,
    439 	    "usage: %s [-R [-H | -L | -P]] [-f | -i] [-alNpv] src target\n"
    440 	    "       %s [-R [-H | -L | -P]] [-f | -i] [-alNpv] src1 ... srcN directory\n",
    441 	    getprogname(), getprogname());
    442 	exit(1);
    443 	/* NOTREACHED */
    444 }
    445