src/detect-virt/detect-virt.c

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