udev/zvol_id.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or https://opensource.org/licenses/CDDL-1.0.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright (c) 2011, Fajar A. Nugraha.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #include <ctype.h>
  27 #include <errno.h>
  28 #include <fcntl.h>
  29 #include <stdio.h>
  30 #include <string.h>
  31 #include <unistd.h>
  32 #include <sys/fs/zfs.h>
  33 #include <sys/ioctl.h>
  34 #include <sys/stat.h>
  35
  36 #if defined(ZFS_ASAN_ENABLED)
  37 /*
  38  * zvol_id is invoked by udev with the help of ptrace()
  39  * making sanitized binary with leak detection croak
  40  * because of tracing mechanisms collision
  41  */
  42 extern const char *__asan_default_options(void);
  43
  44 const char *__asan_default_options(void) {
  45         return ("abort_on_error=true:halt_on_error=true:"
  46                 "allocator_may_return_null=true:disable_coredump=false:"
  47                 "detect_stack_use_after_return=true:detect_leaks=false");
  48 }
  49 #endif
  50
  51 int
  52 main(int argc, const char *const *argv)
  53 {
  54         if (argc != 2) {
  55                 fprintf(stderr, "usage: %s /dev/zdX\n", argv[0]);
  56                 return (1);
  57         }
  58         const char *dev_name = argv[1];
  59
  60         int fd;
  61         struct stat sb;
  62         if ((fd = open(dev_name, O_RDONLY|O_CLOEXEC)) == -1 ||
  63             fstat(fd, &sb) != 0) {
  64                 fprintf(stderr, "%s: %s\n", dev_name, strerror(errno));
  65                 return (1);
  66         }
  67
  68         char zvol_name[MAXNAMELEN + strlen("-part") + 10];
  69         if (ioctl(fd, BLKZNAME, zvol_name) == -1) {
  70                 fprintf(stderr, "%s: BLKZNAME: %s\n",
  71                     dev_name, strerror(errno));
  72                 return (1);
  73         }
  74
  75         unsigned int dev_part = minor(sb.st_rdev) % ZVOL_MINORS;
  76         if (dev_part != 0)
  77                 sprintf(zvol_name + strlen(zvol_name), "-part%u", dev_part);
  78
  79         for (size_t i = 0; i < strlen(zvol_name); ++i)
  80                 if (isblank(zvol_name[i]))
  81                         zvol_name[i] = '+';
  82
  83         puts(zvol_name);
  84
  85         return (0);
  86 }