1 /* SPDX-License-Identifier: CDDL-1.0 OR MPL-2.0 */
2 /*
3 * CDDL HEADER START
4 *
5 * The contents of this file are subject to the terms of the
6 * Common Development and Distribution License (the "License").
7 * You may not use this file except in compliance with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or https://opensource.org/licenses/CDDL-1.0.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22
23 /*
24 * Copyright (C) 2019 Aleksa Sarai <cyphar@cyphar.com>
25 * Copyright (C) 2019 SUSE LLC
26 */
27
28 /*
29 * mv(1) doesn't currently support RENAME_{EXCHANGE,WHITEOUT} so this is a very
30 * simple renameat2(2) wrapper for the OpenZFS self-tests.
31 */
32
33 #include <errno.h>
34 #include <fcntl.h>
35 #include <unistd.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <sys/syscall.h>
40
41 #ifndef SYS_renameat2
42 #ifdef __NR_renameat2
43 #define SYS_renameat2 __NR_renameat2
44 #elif defined(__x86_64__)
45 #define SYS_renameat2 316
46 #elif defined(__i386__)
47 #define SYS_renameat2 353
48 #elif defined(__arm__) || defined(__aarch64__)
49 #define SYS_renameat2 382
50 #else
51 #error "SYS_renameat2 not known for this architecture."
52 #endif
53 #endif
54
55 #ifndef RENAME_NOREPLACE
56 #define RENAME_NOREPLACE (1 << 0) /* Don't overwrite target */
57 #endif
58 #ifndef RENAME_EXCHANGE
59 #define RENAME_EXCHANGE (1 << 1) /* Exchange source and dest */
60 #endif
61 #ifndef RENAME_WHITEOUT
62 #define RENAME_WHITEOUT (1 << 2) /* Whiteout source */
63 #endif
64
65 /* glibc doesn't provide renameat2 wrapper, let's use our own */
66 static int
sys_renameat2(int olddirfd,const char * oldpath,int newdirfd,const char * newpath,unsigned int flags)67 sys_renameat2(int olddirfd, const char *oldpath,
68 int newdirfd, const char *newpath, unsigned int flags)
69 {
70 int ret = syscall(SYS_renameat2, olddirfd, oldpath, newdirfd, newpath,
71 flags);
72 return ((ret < 0) ? -errno : ret);
73 }
74
75 static void
usage(void)76 usage(void)
77 {
78 fprintf(stderr, "usage: renameat2 [-Cnwx] src dst\n");
79 exit(1);
80 }
81
82 static void
check(void)83 check(void)
84 {
85 int err = sys_renameat2(AT_FDCWD, ".", AT_FDCWD, ".", RENAME_EXCHANGE);
86 exit(err == -ENOSYS);
87 }
88
89 int
main(int argc,char ** argv)90 main(int argc, char **argv)
91 {
92 char *src, *dst;
93 int ch, err;
94 unsigned int flags = 0;
95
96 while ((ch = getopt(argc, argv, "Cnwx")) >= 0) {
97 switch (ch) {
98 case 'C':
99 check();
100 break;
101 case 'n':
102 flags |= RENAME_NOREPLACE;
103 break;
104 case 'w':
105 flags |= RENAME_WHITEOUT;
106 break;
107 case 'x':
108 flags |= RENAME_EXCHANGE;
109 break;
110 default:
111 usage();
112 break;
113 }
114 }
115
116 argc -= optind;
117 argv += optind;
118
119 if (argc != 2)
120 usage();
121 src = argv[0];
122 dst = argv[1];
123
124 err = sys_renameat2(AT_FDCWD, src, AT_FDCWD, dst, flags);
125 if (err < 0)
126 fprintf(stderr, "renameat2: %s", strerror(-err));
127 return (err != 0);
128 }
129