xref: /freebsd/bin/cp/utils.c (revision 3193579b66fd7067f898dbc54bdea81a0e6f9bd0)
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 
34 #ifndef lint
35 #if 0
36 static char sccsid[] = "@(#)utils.c	8.3 (Berkeley) 4/1/94";
37 #endif
38 #endif /* not lint */
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 #include <sys/param.h>
43 #include <sys/stat.h>
44 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
45 #include <sys/mman.h>
46 #endif
47 
48 #include <err.h>
49 #include <errno.h>
50 #include <fcntl.h>
51 #include <fts.h>
52 #include <limits.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <sysexits.h>
56 #include <unistd.h>
57 
58 #include "extern.h"
59 #define	cp_pct(x,y)	(int)(100.0 * (double)(x) / (double)(y))
60 
61 int
62 copy_file(const FTSENT *entp, int dne)
63 {
64 	static char buf[MAXBSIZE];
65 	struct stat *fs;
66 	int ch, checkch, from_fd, rcount, rval, to_fd;
67 	ssize_t wcount;
68 	size_t wresid;
69 	size_t wtotal;
70 	char *bufp;
71 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
72 	char *p;
73 #endif
74 
75 	if ((from_fd = open(entp->fts_path, O_RDONLY, 0)) == -1) {
76 		warn("%s", entp->fts_path);
77 		return (1);
78 	}
79 
80 	fs = entp->fts_statp;
81 
82 	/*
83 	 * If the file exists and we're interactive, verify with the user.
84 	 * If the file DNE, set the mode to be the from file, minus setuid
85 	 * bits, modified by the umask; arguably wrong, but it makes copying
86 	 * executables work right and it's been that way forever.  (The
87 	 * other choice is 666 or'ed with the execute bits on the from file
88 	 * modified by the umask.)
89 	 */
90 	if (!dne) {
91 #define YESNO "(y/n [n]) "
92 		if (nflag) {
93 			if (vflag)
94 				printf("%s not overwritten\n", to.p_path);
95 			return (0);
96 		} else if (iflag) {
97 			(void)fprintf(stderr, "overwrite %s? %s",
98 					to.p_path, YESNO);
99 			checkch = ch = getchar();
100 			while (ch != '\n' && ch != EOF)
101 				ch = getchar();
102 			if (checkch != 'y' && checkch != 'Y') {
103 				(void)close(from_fd);
104 				(void)fprintf(stderr, "not overwritten\n");
105 				return (1);
106 			}
107 		}
108 
109 		if (fflag) {
110 		    /* remove existing destination file name,
111 		     * create a new file  */
112 		    (void)unlink(to.p_path);
113 		    to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
114 				 fs->st_mode & ~(S_ISUID | S_ISGID));
115 		} else
116 		    /* overwrite existing destination file name */
117 		    to_fd = open(to.p_path, O_WRONLY | O_TRUNC, 0);
118 	} else
119 		to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
120 		    fs->st_mode & ~(S_ISUID | S_ISGID));
121 
122 	if (to_fd == -1) {
123 		warn("%s", to.p_path);
124 		(void)close(from_fd);
125 		return (1);
126 	}
127 
128 	rval = 0;
129 
130 	/*
131 	 * Mmap and write if less than 8M (the limit is so we don't totally
132 	 * trash memory on big files.  This is really a minor hack, but it
133 	 * wins some CPU back.
134 	 */
135 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
136 	if (S_ISREG(fs->st_mode) && fs->st_size > 0 &&
137 	    fs->st_size <= 8 * 1048576) {
138 		if ((p = mmap(NULL, (size_t)fs->st_size, PROT_READ,
139 		    MAP_SHARED, from_fd, (off_t)0)) == MAP_FAILED) {
140 			warn("%s", entp->fts_path);
141 			rval = 1;
142 		} else {
143 			wtotal = 0;
144 			for (bufp = p, wresid = fs->st_size; ;
145 			    bufp += wcount, wresid -= (size_t)wcount) {
146 				wcount = write(to_fd, bufp, wresid);
147 				wtotal += wcount;
148 				if (info) {
149 					info = 0;
150 					(void)fprintf(stderr,
151 						"%s -> %s %3d%%\n",
152 						entp->fts_path, to.p_path,
153 						cp_pct(wtotal, fs->st_size));
154 
155 				}
156 				if (wcount >= (ssize_t)wresid || wcount <= 0)
157 					break;
158 			}
159 			if (wcount != (ssize_t)wresid) {
160 				warn("%s", to.p_path);
161 				rval = 1;
162 			}
163 			/* Some systems don't unmap on close(2). */
164 			if (munmap(p, fs->st_size) < 0) {
165 				warn("%s", entp->fts_path);
166 				rval = 1;
167 			}
168 		}
169 	} else
170 #endif
171 	{
172 		wtotal = 0;
173 		while ((rcount = read(from_fd, buf, MAXBSIZE)) > 0) {
174 			for (bufp = buf, wresid = rcount; ;
175 			    bufp += wcount, wresid -= wcount) {
176 				wcount = write(to_fd, bufp, wresid);
177 				wtotal += wcount;
178 				if (info) {
179 					info = 0;
180 					(void)fprintf(stderr,
181 						"%s -> %s %3d%%\n",
182 						entp->fts_path, to.p_path,
183 						cp_pct(wtotal, fs->st_size));
184 
185 				}
186 				if (wcount >= (ssize_t)wresid || wcount <= 0)
187 					break;
188 			}
189 			if (wcount != (ssize_t)wresid) {
190 				warn("%s", to.p_path);
191 				rval = 1;
192 				break;
193 			}
194 		}
195 		if (rcount < 0) {
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 	(void)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 llink[PATH_MAX];
223 
224 	if ((len = readlink(p->fts_path, llink, sizeof(llink) - 1)) == -1) {
225 		warn("readlink: %s", p->fts_path);
226 		return (1);
227 	}
228 	llink[len] = '\0';
229 	if (exists && unlink(to.p_path)) {
230 		warn("unlink: %s", to.p_path);
231 		return (1);
232 	}
233 	if (symlink(llink, to.p_path)) {
234 		warn("symlink: %s", llink);
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 = ENOSYS) :
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 
336 	(void)fprintf(stderr, "%s\n%s\n",
337 "usage: cp [-R [-H | -L | -P]] [-f | -i | -n] [-pv] src target",
338 "       cp [-R [-H | -L | -P]] [-f | -i | -n] [-pv] src1 ... srcN directory");
339 	exit(EX_USAGE);
340 }
341