xref: /freebsd/bin/cp/utils.c (revision 7660b554bc59a07be0431c17e0e33815818baa69)
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 <= 8 * 1048576) {
137 		if ((p = mmap(NULL, (size_t)fs->st_size, PROT_READ,
138 		    MAP_SHARED, from_fd, (off_t)0)) == MAP_FAILED) {
139 			warn("%s", entp->fts_path);
140 			rval = 1;
141 		} else {
142 			wtotal = 0;
143 			for (bufp = p, wresid = fs->st_size; ;
144 			    bufp += wcount, wresid -= (size_t)wcount) {
145 				wcount = write(to_fd, bufp, wresid);
146 				wtotal += wcount;
147 				if (info) {
148 					info = 0;
149 					(void)fprintf(stderr,
150 						"%s -> %s %3d%%\n",
151 						entp->fts_path, to.p_path,
152 						cp_pct(wtotal, fs->st_size));
153 
154 				}
155 				if (wcount >= (ssize_t)wresid || wcount <= 0)
156 					break;
157 			}
158 			if (wcount != (ssize_t)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 ((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 				wtotal += wcount;
177 				if (info) {
178 					info = 0;
179 					(void)fprintf(stderr,
180 						"%s -> %s %3d%%\n",
181 						entp->fts_path, to.p_path,
182 						cp_pct(wtotal, fs->st_size));
183 
184 				}
185 				if (wcount >= (ssize_t)wresid || wcount <= 0)
186 					break;
187 			}
188 			if (wcount != (ssize_t)wresid) {
189 				warn("%s", to.p_path);
190 				rval = 1;
191 				break;
192 			}
193 		}
194 		if (rcount < 0) {
195 			warn("%s", entp->fts_path);
196 			rval = 1;
197 		}
198 	}
199 
200 	/*
201 	 * Don't remove the target even after an error.  The target might
202 	 * not be a regular file, or its attributes might be important,
203 	 * or its contents might be irreplaceable.  It would only be safe
204 	 * to remove it if we created it and its length is 0.
205 	 */
206 
207 	if (pflag && setfile(fs, to_fd))
208 		rval = 1;
209 	(void)close(from_fd);
210 	if (close(to_fd)) {
211 		warn("%s", to.p_path);
212 		rval = 1;
213 	}
214 	return (rval);
215 }
216 
217 int
218 copy_link(const FTSENT *p, int exists)
219 {
220 	int len;
221 	char llink[PATH_MAX];
222 
223 	if ((len = readlink(p->fts_path, llink, sizeof(llink) - 1)) == -1) {
224 		warn("readlink: %s", p->fts_path);
225 		return (1);
226 	}
227 	llink[len] = '\0';
228 	if (exists && unlink(to.p_path)) {
229 		warn("unlink: %s", to.p_path);
230 		return (1);
231 	}
232 	if (symlink(llink, to.p_path)) {
233 		warn("symlink: %s", llink);
234 		return (1);
235 	}
236 	return (pflag ? setfile(p->fts_statp, -1) : 0);
237 }
238 
239 int
240 copy_fifo(struct stat *from_stat, int exists)
241 {
242 	if (exists && unlink(to.p_path)) {
243 		warn("unlink: %s", to.p_path);
244 		return (1);
245 	}
246 	if (mkfifo(to.p_path, from_stat->st_mode)) {
247 		warn("mkfifo: %s", to.p_path);
248 		return (1);
249 	}
250 	return (pflag ? setfile(from_stat, -1) : 0);
251 }
252 
253 int
254 copy_special(struct stat *from_stat, int exists)
255 {
256 	if (exists && unlink(to.p_path)) {
257 		warn("unlink: %s", to.p_path);
258 		return (1);
259 	}
260 	if (mknod(to.p_path, from_stat->st_mode, from_stat->st_rdev)) {
261 		warn("mknod: %s", to.p_path);
262 		return (1);
263 	}
264 	return (pflag ? setfile(from_stat, -1) : 0);
265 }
266 
267 int
268 setfile(struct stat *fs, int fd)
269 {
270 	static struct timeval tv[2];
271 	struct stat ts;
272 	int rval, gotstat, islink, fdval;
273 
274 	rval = 0;
275 	fdval = fd != -1;
276 	islink = !fdval && S_ISLNK(fs->st_mode);
277 	fs->st_mode &= S_ISUID | S_ISGID | S_ISVTX |
278 		       S_IRWXU | S_IRWXG | S_IRWXO;
279 
280 	TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
281 	TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
282 	if (islink ? lutimes(to.p_path, tv) : utimes(to.p_path, tv)) {
283 		warn("%sutimes: %s", islink ? "l" : "", to.p_path);
284 		rval = 1;
285 	}
286 	if (fdval ? fstat(fd, &ts) :
287 	    (islink ? lstat(to.p_path, &ts) : stat(to.p_path, &ts)))
288 		gotstat = 0;
289 	else {
290 		gotstat = 1;
291 		ts.st_mode &= S_ISUID | S_ISGID | S_ISVTX |
292 			      S_IRWXU | S_IRWXG | S_IRWXO;
293 	}
294 	/*
295 	 * Changing the ownership probably won't succeed, unless we're root
296 	 * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
297 	 * the mode; current BSD behavior is to remove all setuid bits on
298 	 * chown.  If chown fails, lose setuid/setgid bits.
299 	 */
300 	if (!gotstat || fs->st_uid != ts.st_uid || fs->st_gid != ts.st_gid)
301 		if (fdval ? fchown(fd, fs->st_uid, fs->st_gid) :
302 		    (islink ? lchown(to.p_path, fs->st_uid, fs->st_gid) :
303 		    chown(to.p_path, fs->st_uid, fs->st_gid))) {
304 			if (errno != EPERM) {
305 				warn("chown: %s", to.p_path);
306 				rval = 1;
307 			}
308 			fs->st_mode &= ~(S_ISUID | S_ISGID);
309 		}
310 
311 	if (!gotstat || fs->st_mode != ts.st_mode)
312 		if (fdval ? fchmod(fd, fs->st_mode) :
313 		    (islink ? lchmod(to.p_path, fs->st_mode) :
314 		    chmod(to.p_path, fs->st_mode))) {
315 			warn("chmod: %s", to.p_path);
316 			rval = 1;
317 		}
318 
319 	if (!gotstat || fs->st_flags != ts.st_flags)
320 		if (fdval ?
321 		    fchflags(fd, fs->st_flags) :
322 		    (islink ? (errno = ENOSYS) :
323 		    chflags(to.p_path, fs->st_flags))) {
324 			warn("chflags: %s", to.p_path);
325 			rval = 1;
326 		}
327 
328 	return (rval);
329 }
330 
331 void
332 usage(void)
333 {
334 
335 	(void)fprintf(stderr, "%s\n%s\n",
336 "usage: cp [-R [-H | -L | -P]] [-f | -i | -n] [-pv] src target",
337 "       cp [-R [-H | -L | -P]] [-f | -i | -n] [-pv] src1 ... srcN directory");
338 	exit(EX_USAGE);
339 }
340