src/detect-virt/detect-virt.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2010 Lennart Poettering
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <errno.h>
  21 #include <getopt.h>
  22 #include <stdbool.h>
  23 #include <stdlib.h>
  24
  25 #include "util.h"
  26 #include "virt.h"
  27
  28 static bool arg_quiet = false;
  29 static enum {
  30         ANY_VIRTUALIZATION,
  31         ONLY_VM,
  32         ONLY_CONTAINER,
  33         ONLY_CHROOT,
  34 } arg_mode = ANY_VIRTUALIZATION;
  35
  36 static void help(void) {
  37         printf("%s [OPTIONS...]\n\n"
  38                "Detect execution in a virtualized environment.\n\n"
  39                "  -h --help             Show this help\n"
  40                "     --version          Show package version\n"
  41                "  -c --container        Only detect whether we are run in a container\n"
  42                "  -v --vm               Only detect whether we are run in a VM\n"
  43                "  -r --chroot           Detect whether we are run in a chroot() environment\n"
  44                "  -q --quiet            Don't output anything, just set return value\n"
  45                , program_invocation_short_name);
  46 }
  47
  48 static int parse_argv(int argc, char *argv[]) {
  49
  50         enum {
  51                 ARG_VERSION = 0x100
  52         };
  53
  54         static const struct option options[] = {
  55                 { "help",      no_argument,       NULL, 'h'           },
  56                 { "version",   no_argument,       NULL, ARG_VERSION   },
  57                 { "container", no_argument,       NULL, 'c'           },
  58                 { "vm",        no_argument,       NULL, 'v'           },
  59                 { "chroot",    no_argument,       NULL, 'r'           },
  60                 { "quiet",     no_argument,       NULL, 'q'           },
  61                 {}
  62         };
  63
  64         int c;
  65
  66         assert(argc >= 0);
  67         assert(argv);
  68
  69         while ((c = getopt_long(argc, argv, "hqcvr", options, NULL)) >= 0)
  70
  71                 switch (c) {
  72
  73                 case 'h':
  74                         help();
  75                         return 0;
  76
  77                 case ARG_VERSION:
  78                         return version();
  79
  80                 case 'q':
  81                         arg_quiet = true;
  82                         break;
  83
  84                 case 'c':
  85                         arg_mode = ONLY_CONTAINER;
  86                         break;
  87
  88                 case 'v':
  89                         arg_mode = ONLY_VM;
  90                         break;
  91
  92                 case 'r':
  93                         arg_mode = ONLY_CHROOT;
  94                         break;
  95
  96                 case '?':
  97                         return -EINVAL;
  98
  99                 default:
 100                         assert_not_reached("Unhandled option");
 101                 }
 102
 103         if (optind < argc) {
 104                 log_error("%s takes no arguments.", program_invocation_short_name);
 105                 return -EINVAL;
 106         }
 107
 108         return 1;
 109 }
 110
 111 int main(int argc, char *argv[]) {
 112         int r;
 113
 114         /* This is mostly intended to be used for scripts which want
 115          * to detect whether we are being run in a virtualized
 116          * environment or not */
 117
 118         log_parse_environment();
 119         log_open();
 120
 121         r = parse_argv(argc, argv);
 122         if (r <= 0)
 123                 return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 124
 125         switch (arg_mode) {
 126
 127         case ONLY_VM:
 128                 r = detect_vm();
 129                 if (r < 0) {
 130                         log_error_errno(r, "Failed to check for VM: %m");
 131                         return EXIT_FAILURE;
 132                 }
 133
 134                 break;
 135
 136         case ONLY_CONTAINER:
 137                 r = detect_container();
 138                 if (r < 0) {
 139                         log_error_errno(r, "Failed to check for container: %m");
 140                         return EXIT_FAILURE;
 141                 }
 142
 143                 break;
 144
 145         case ONLY_CHROOT:
 146                 r = running_in_chroot();
 147                 if (r < 0) {
 148                         log_error_errno(r, "Failed to check for chroot() environment: %m");
 149                         return EXIT_FAILURE;
 150                 }
 151
 152                 return r ? EXIT_SUCCESS : EXIT_FAILURE;
 153
 154         case ANY_VIRTUALIZATION:
 155         default:
 156                 r = detect_virtualization();
 157                 if (r < 0) {
 158                         log_error_errno(r, "Failed to check for virtualization: %m");
 159                         return EXIT_FAILURE;
 160                 }
 161
 162                 break;
 163         }
 164
 165         if (!arg_quiet)
 166                 puts(virtualization_to_string(r));
 167
 168         return r != VIRTUALIZATION_NONE ? EXIT_SUCCESS : EXIT_FAILURE;
 169 }