xref: /netbsd-src/bin/cp/utils.c (revision a5a68ff5f29de57339ca14f6c671c0a87714f1f8)
1 /*	$NetBSD: utils.c,v 1.8 1997/07/20 05:13:37 thorpej 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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)utils.c	8.3 (Berkeley) 4/1/94";
40 #else
41 __RCSID("$NetBSD: utils.c,v 1.8 1997/07/20 05:13:37 thorpej Exp $");
42 #endif
43 #endif /* not lint */
44 
45 #include <sys/param.h>
46 #include <sys/stat.h>
47 #include <sys/mman.h>
48 #include <sys/time.h>
49 
50 #include <err.h>
51 #include <errno.h>
52 #include <fcntl.h>
53 #include <fts.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <unistd.h>
58 
59 #include "extern.h"
60 
61 int
62 copy_file(entp, dne)
63 	FTSENT *entp;
64 	int dne;
65 {
66 	static char buf[MAXBSIZE];
67 	struct stat to_stat, *fs;
68 	int ch, checkch, from_fd, rcount, rval, to_fd, wcount;
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 (iflag) {
90 			(void)fprintf(stderr, "overwrite %s? ", to.p_path);
91 			checkch = ch = getchar();
92 			while (ch != '\n' && ch != EOF)
93 				ch = getchar();
94 			if (checkch != 'y' && checkch != 'Y') {
95 				(void)close(from_fd);
96 				return (0);
97 			}
98 		}
99 		to_fd = open(to.p_path, O_WRONLY | O_TRUNC, 0);
100 	} else
101 		to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
102 		    fs->st_mode & ~(S_ISUID | S_ISGID));
103 
104 	if (to_fd == -1) {
105 		warn("%s", to.p_path);
106 		(void)close(from_fd);
107 		return (1);;
108 	}
109 
110 	rval = 0;
111 
112 	/*
113 	 * Mmap and write if less than 8M (the limit is so we don't totally
114 	 * trash memory on big files.  This is really a minor hack, but it
115 	 * wins some CPU back.
116 	 */
117 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
118 	if (fs->st_size <= 8 * 1048576) {
119 		if ((p = mmap(NULL, (size_t)fs->st_size, PROT_READ,
120 		    0, from_fd, (off_t)0)) == (char *)-1) {
121 			warn("%s", entp->fts_path);
122 			rval = 1;
123 		} else {
124 			if (write(to_fd, p, fs->st_size) != fs->st_size) {
125 				warn("%s", to.p_path);
126 				rval = 1;
127 			}
128 			/* Some systems don't unmap on close(2). */
129 			if (munmap(p, fs->st_size) < 0) {
130 				warn("%s", entp->fts_path);
131 				rval = 1;
132 			}
133 		}
134 	} else
135 #endif
136 	{
137 		while ((rcount = read(from_fd, buf, MAXBSIZE)) > 0) {
138 			wcount = write(to_fd, buf, rcount);
139 			if (rcount != wcount || wcount == -1) {
140 				warn("%s", to.p_path);
141 				rval = 1;
142 				break;
143 			}
144 		}
145 		if (rcount < 0) {
146 			warn("%s", entp->fts_path);
147 			rval = 1;
148 		}
149 	}
150 
151 	if (rval == 1) {
152 		(void)close(from_fd);
153 		(void)close(to_fd);
154 		return (1);
155 	}
156 
157 	if (pflag && setfile(fs, to_fd))
158 		rval = 1;
159 	/*
160 	 * If the source was setuid or setgid, lose the bits unless the
161 	 * copy is owned by the same user and group.
162 	 */
163 #define	RETAINBITS \
164 	(S_ISUID | S_ISGID | S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO)
165 	else if (fs->st_mode & (S_ISUID | S_ISGID) && fs->st_uid == myuid)
166 		if (fstat(to_fd, &to_stat)) {
167 			warn("%s", to.p_path);
168 			rval = 1;
169 		} else if (fs->st_gid == to_stat.st_gid &&
170 		    fchmod(to_fd, fs->st_mode & RETAINBITS & ~myumask)) {
171 			warn("%s", to.p_path);
172 			rval = 1;
173 		}
174 	(void)close(from_fd);
175 	if (close(to_fd)) {
176 		warn("%s", to.p_path);
177 		rval = 1;
178 	}
179 	return (rval);
180 }
181 
182 int
183 copy_link(p, exists)
184 	FTSENT *p;
185 	int exists;
186 {
187 	int len;
188 	char link[MAXPATHLEN];
189 
190 	if ((len = readlink(p->fts_path, link, sizeof(link))) == -1) {
191 		warn("readlink: %s", p->fts_path);
192 		return (1);
193 	}
194 	link[len] = '\0';
195 	if (exists && unlink(to.p_path)) {
196 		warn("unlink: %s", to.p_path);
197 		return (1);
198 	}
199 	if (symlink(link, to.p_path)) {
200 		warn("symlink: %s", link);
201 		return (1);
202 	}
203 	return (0);
204 }
205 
206 int
207 copy_fifo(from_stat, exists)
208 	struct stat *from_stat;
209 	int exists;
210 {
211 	if (exists && unlink(to.p_path)) {
212 		warn("unlink: %s", to.p_path);
213 		return (1);
214 	}
215 	if (mkfifo(to.p_path, from_stat->st_mode)) {
216 		warn("mkfifo: %s", to.p_path);
217 		return (1);
218 	}
219 	return (pflag ? setfile(from_stat, 0) : 0);
220 }
221 
222 int
223 copy_special(from_stat, exists)
224 	struct stat *from_stat;
225 	int exists;
226 {
227 	if (exists && unlink(to.p_path)) {
228 		warn("unlink: %s", to.p_path);
229 		return (1);
230 	}
231 	if (mknod(to.p_path, from_stat->st_mode, from_stat->st_rdev)) {
232 		warn("mknod: %s", to.p_path);
233 		return (1);
234 	}
235 	return (pflag ? setfile(from_stat, 0) : 0);
236 }
237 
238 
239 int
240 setfile(fs, fd)
241 	struct stat *fs;
242 	int fd;
243 {
244 	static struct timeval tv[2];
245 	int rval;
246 
247 	rval = 0;
248 	fs->st_mode &= S_ISUID | S_ISGID | S_IRWXU | S_IRWXG | S_IRWXO;
249 
250 	TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
251 	TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
252 	if (utimes(to.p_path, tv)) {
253 		warn("utimes: %s", to.p_path);
254 		rval = 1;
255 	}
256 	/*
257 	 * Changing the ownership probably won't succeed, unless we're root
258 	 * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
259 	 * the mode; current BSD behavior is to remove all setuid bits on
260 	 * chown.  If chown fails, lose setuid/setgid bits.
261 	 */
262 	if (fd ? fchown(fd, fs->st_uid, fs->st_gid) :
263 	    chown(to.p_path, fs->st_uid, fs->st_gid)) {
264 		if (errno != EPERM) {
265 			warn("chown: %s", to.p_path);
266 			rval = 1;
267 		}
268 		fs->st_mode &= ~(S_ISUID | S_ISGID);
269 	}
270 	if (fd ? fchmod(fd, fs->st_mode) : chmod(to.p_path, fs->st_mode)) {
271 		warn("chown: %s", to.p_path);
272 		rval = 1;
273 	}
274 
275 	/*
276 	 * XXX
277 	 * NFS doesn't support chflags; ignore errors unless there's reason
278 	 * to believe we're losing bits.  (Note, this still won't be right
279 	 * if the server supports flags and we were trying to *remove* flags
280 	 * on a file that we copied, i.e., that we didn't create.)
281 	 */
282 	errno = 0;
283 	if (fd ? fchflags(fd, fs->st_flags) : chflags(to.p_path, fs->st_flags))
284 		if (errno != EOPNOTSUPP || fs->st_flags != 0) {
285 			warn("chflags: %s", to.p_path);
286 			rval = 1;
287 		}
288 	return (rval);
289 }
290 
291 void
292 usage()
293 {
294 	(void)fprintf(stderr, "%s\n%s\n",
295 	    "usage: cp [-R [-H | -L | -P]] [-fip] src target",
296 	    "       cp [-R [-H | -L | -P]] [-fip] src1 ... srcN directory");
297 	exit(1);
298 }
299