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 <stdlib.h>
  23 #include <stdbool.h>
  24 #include <errno.h>
  25 #include <string.h>
  26 #include <getopt.h>
  27
  28 #include "util.h"
  29 #include "virt.h"
  30 #include "build.h"
  31
  32 static bool arg_quiet = false;
  33 static enum {
  34         ANY_VIRTUALIZATION,
  35         ONLY_VM,
  36         ONLY_CONTAINER
  37 } arg_mode = ANY_VIRTUALIZATION;
  38
  39 static void help(void) {
  40         printf("%s [OPTIONS...]\n\n"
  41                "Detect execution in a virtualized environment.\n\n"
  42                "  -h --help             Show this help\n"
  43                "     --version          Show package version\n"
  44                "  -c --container        Only detect whether we are run in a container\n"
  45                "  -v --vm               Only detect whether we are run in a VM\n"
  46                "  -q --quiet            Don't output anything, just set return value\n"
  47                , program_invocation_short_name);
  48 }
  49
  50 static int parse_argv(int argc, char *argv[]) {
  51
  52         enum {
  53                 ARG_VERSION = 0x100
  54         };
  55
  56         static const struct option options[] = {
  57                 { "help",      no_argument,       NULL, 'h'           },
  58                 { "version",   no_argument,       NULL, ARG_VERSION   },
  59                 { "container", no_argument,       NULL, 'c'           },
  60                 { "vm",        optional_argument, NULL, 'v'           },
  61                 { "quiet",     no_argument,       NULL, 'q'           },
  62                 {}
  63         };
  64
  65         int c;
  66
  67         assert(argc >= 0);
  68         assert(argv);
  69
  70         while ((c = getopt_long(argc, argv, "hqcv", options, NULL)) >= 0)
  71
  72                 switch (c) {
  73
  74                 case 'h':
  75                         help();
  76                         return 0;
  77
  78                 case ARG_VERSION:
  79                         puts(PACKAGE_STRING);
  80                         puts(SYSTEMD_FEATURES);
  81                         return 0;
  82
  83                 case 'q':
  84                         arg_quiet = true;
  85                         break;
  86
  87                 case 'c':
  88                         arg_mode = ONLY_CONTAINER;
  89                         break;
  90
  91                 case 'v':
  92                         arg_mode = ONLY_VM;
  93                         break;
  94
  95                 case '?':
  96                         return -EINVAL;
  97
  98                 default:
  99                         assert_not_reached("Unhandled option");
 100                 }
 101
 102         if (optind < argc) {
 103                 log_error("%s takes no arguments.",
 104                           program_invocation_short_name);
 105                 return -EINVAL;
 106         }
 107
 108         return 1;
 109 }
 110
 111 int main(int argc, char *argv[]) {
 112         const char *id = NULL;
 113         int retval = EXIT_SUCCESS;
 114         int r;
 115
 116         /* This is mostly intended to be used for scripts which want
 117          * to detect whether we are being run in a virtualized
 118          * environment or not */
 119
 120         log_parse_environment();
 121         log_open();
 122
 123         r = parse_argv(argc, argv);
 124         if (r <= 0)
 125                 return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 126
 127         switch (arg_mode) {
 128
 129         case ANY_VIRTUALIZATION: {
 130                 int v;
 131
 132                 v = detect_virtualization(&id);
 133                 if (v < 0) {
 134                         log_error_errno(v, "Failed to check for virtualization: %m");
 135                         return EXIT_FAILURE;
 136                 }
 137
 138                 retval = v != VIRTUALIZATION_NONE ? EXIT_SUCCESS : EXIT_FAILURE;
 139                 break;
 140         }
 141
 142         case ONLY_CONTAINER:
 143                 r = detect_container(&id);
 144                 if (r < 0) {
 145                         log_error_errno(r, "Failed to check for container: %m");
 146                         return EXIT_FAILURE;
 147                 }
 148
 149                 retval = r > 0 ? EXIT_SUCCESS : EXIT_FAILURE;
 150                 break;
 151
 152         case ONLY_VM:
 153                 r = detect_vm(&id);
 154                 if (r < 0) {
 155                         log_error_errno(r, "Failed to check for vm: %m");
 156                         return EXIT_FAILURE;
 157                 }
 158
 159                 retval = r > 0 ? EXIT_SUCCESS : EXIT_FAILURE;
 160                 break;
 161         }
 162
 163         if (!arg_quiet)
 164                 puts(id ? id : "none");
 165
 166         return retval;
 167 }