tests/zfs-tests/cmd/renameat2.c

   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
  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
  76 usage(void)
  77 {
  78         fprintf(stderr, "usage: renameat2 [-Cnwx] src dst\n");
  79         exit(1);
  80 }
  81
  82 static void
  83 check(void)
  84 {
  85         int err = sys_renameat2(AT_FDCWD, ".", AT_FDCWD, ".", RENAME_EXCHANGE);
  86         exit(err == -ENOSYS);
  87 }
  88
  89 int
  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 }