src/login/inhibit.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   This file is part of systemd.
   4
   5   Copyright 2012 Lennart Poettering
   6 ***/
   7
   8 #include <fcntl.h>
   9 #include <getopt.h>
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <unistd.h>
  13
  14 #include "sd-bus.h"
  15
  16 #include "alloc-util.h"
  17 #include "bus-error.h"
  18 #include "bus-util.h"
  19 #include "fd-util.h"
  20 #include "format-util.h"
  21 #include "process-util.h"
  22 #include "signal-util.h"
  23 #include "strv.h"
  24 #include "user-util.h"
  25 #include "util.h"
  26
  27 /// Additional includes needed by elogind
  28 #include "musl_missing.h"
  29
  30 static const char* arg_what = "idle:sleep:shutdown";
  31 static const char* arg_who = NULL;
  32 static const char* arg_why = "Unknown reason";
  33 static const char* arg_mode = NULL;
  34
  35 static enum {
  36         ACTION_INHIBIT,
  37         ACTION_LIST
  38 } arg_action = ACTION_INHIBIT;
  39
  40 static int inhibit(sd_bus *bus, sd_bus_error *error) {
  41         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
  42         int r;
  43         int fd;
  44
  45         r = sd_bus_call_method(
  46                         bus,
  47                         "org.freedesktop.login1",
  48                         "/org/freedesktop/login1",
  49                         "org.freedesktop.login1.Manager",
  50                         "Inhibit",
  51                         error,
  52                         &reply,
  53                         "ssss", arg_what, arg_who, arg_why, arg_mode);
  54         if (r < 0)
  55                 return r;
  56
  57         r = sd_bus_message_read_basic(reply, SD_BUS_TYPE_UNIX_FD, &fd);
  58         if (r < 0)
  59                 return r;
  60
  61         r = fcntl(fd, F_DUPFD_CLOEXEC, 3);
  62         if (r < 0)
  63                 return -errno;
  64
  65         return r;
  66 }
  67
  68 static int print_inhibitors(sd_bus *bus, sd_bus_error *error) {
  69         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
  70         const char *what, *who, *why, *mode;
  71         unsigned int uid, pid;
  72         unsigned n = 0;
  73         int r;
  74
  75         r = sd_bus_call_method(
  76                         bus,
  77                         "org.freedesktop.login1",
  78                         "/org/freedesktop/login1",
  79                         "org.freedesktop.login1.Manager",
  80                         "ListInhibitors",
  81                         error,
  82                         &reply,
  83                         "");
  84         if (r < 0)
  85                 return r;
  86
  87         r = sd_bus_message_enter_container(reply, SD_BUS_TYPE_ARRAY, "(ssssuu)");
  88         if (r < 0)
  89                 return bus_log_parse_error(r);
  90
  91         while ((r = sd_bus_message_read(reply, "(ssssuu)", &what, &who, &why, &mode, &uid, &pid)) > 0) {
  92                 _cleanup_free_ char *comm = NULL, *u = NULL;
  93
  94                 if (arg_mode && !streq(mode, arg_mode))
  95                         continue;
  96
  97                 get_process_comm(pid, &comm);
  98                 u = uid_to_name(uid);
  99
 100                 printf("     Who: %s (UID "UID_FMT"/%s, PID "PID_FMT"/%s)\n"
 101                        "    What: %s\n"
 102                        "     Why: %s\n"
 103                        "    Mode: %s\n\n",
 104                        who, uid, strna(u), pid, strna(comm),
 105                        what,
 106                        why,
 107                        mode);
 108
 109                 n++;
 110         }
 111         if (r < 0)
 112                 return bus_log_parse_error(r);
 113
 114         r = sd_bus_message_exit_container(reply);
 115         if (r < 0)
 116                 return bus_log_parse_error(r);
 117
 118         printf("%u inhibitors listed.\n", n);
 119         return 0;
 120 }
 121
 122 static void help(void) {
 123         printf("%s [OPTIONS...] {COMMAND} ...\n\n"
 124                "Execute a process while inhibiting shutdown/sleep/idle.\n\n"
 125                "  -h --help               Show this help\n"
 126                "     --version            Show package version\n"
 127                "     --what=WHAT          Operations to inhibit, colon separated list of:\n"
 128                "                          shutdown, sleep, idle, handle-power-key,\n"
 129                "                          handle-suspend-key, handle-hibernate-key,\n"
 130                "                          handle-lid-switch\n"
 131                "     --who=STRING         A descriptive string who is inhibiting\n"
 132                "     --why=STRING         A descriptive string why is being inhibited\n"
 133                "     --mode=MODE          One of block or delay\n"
 134                "     --list               List active inhibitors\n"
 135                , program_invocation_short_name);
 136 }
 137
 138 static int parse_argv(int argc, char *argv[]) {
 139
 140         enum {
 141                 ARG_VERSION = 0x100,
 142                 ARG_WHAT,
 143                 ARG_WHO,
 144                 ARG_WHY,
 145                 ARG_MODE,
 146                 ARG_LIST,
 147         };
 148
 149         static const struct option options[] = {
 150                 { "help",         no_argument,       NULL, 'h'              },
 151                 { "version",      no_argument,       NULL, ARG_VERSION      },
 152                 { "what",         required_argument, NULL, ARG_WHAT         },
 153                 { "who",          required_argument, NULL, ARG_WHO          },
 154                 { "why",          required_argument, NULL, ARG_WHY          },
 155                 { "mode",         required_argument, NULL, ARG_MODE         },
 156                 { "list",         no_argument,       NULL, ARG_LIST         },
 157                 {}
 158         };
 159
 160         int c;
 161
 162         assert(argc >= 0);
 163         assert(argv);
 164
 165         while ((c = getopt_long(argc, argv, "+h", options, NULL)) >= 0)
 166
 167                 switch (c) {
 168
 169                 case 'h':
 170                         help();
 171                         return 0;
 172
 173                 case ARG_VERSION:
 174                         return version();
 175
 176                 case ARG_WHAT:
 177                         arg_what = optarg;
 178                         break;
 179
 180                 case ARG_WHO:
 181                         arg_who = optarg;
 182                         break;
 183
 184                 case ARG_WHY:
 185                         arg_why = optarg;
 186                         break;
 187
 188                 case ARG_MODE:
 189                         arg_mode = optarg;
 190                         break;
 191
 192                 case ARG_LIST:
 193                         arg_action = ACTION_LIST;
 194                         break;
 195
 196                 case '?':
 197                         return -EINVAL;
 198
 199                 default:
 200                         assert_not_reached("Unhandled option");
 201                 }
 202
 203         if (arg_action == ACTION_INHIBIT && optind == argc)
 204                 arg_action = ACTION_LIST;
 205
 206         else if (arg_action == ACTION_INHIBIT && optind >= argc) {
 207                 log_error("Missing command line to execute.");
 208                 return -EINVAL;
 209         }
 210
 211         return 1;
 212 }
 213
 214 int main(int argc, char *argv[]) {
 215         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 216         _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
 217         int r;
 218
 219         elogind_set_program_name(argv[0]);
 220         log_parse_environment();
 221         log_open();
 222
 223         r = parse_argv(argc, argv);
 224         if (r < 0)
 225                 return EXIT_FAILURE;
 226         if (r == 0)
 227                 return EXIT_SUCCESS;
 228
 229         r = sd_bus_default_system(&bus);
 230         if (r < 0) {
 231                 log_error_errno(r, "Failed to connect to bus: %m");
 232                 return EXIT_FAILURE;
 233         }
 234
 235         if (arg_action == ACTION_LIST) {
 236
 237                 r = print_inhibitors(bus, &error);
 238                 if (r < 0) {
 239                         log_error("Failed to list inhibitors: %s", bus_error_message(&error, -r));
 240                         return EXIT_FAILURE;
 241                 }
 242
 243         } else {
 244                 _cleanup_close_ int fd = -1;
 245                 _cleanup_free_ char *w = NULL;
 246                 pid_t pid;
 247
 248                 /* Ignore SIGINT and allow the forked process to receive it */
 249                 (void) ignore_signals(SIGINT, -1);
 250
 251                 if (!arg_who)
 252                         arg_who = w = strv_join(argv + optind, " ");
 253
 254                 if (!arg_mode)
 255                         arg_mode = "block";
 256
 257                 fd = inhibit(bus, &error);
 258                 if (fd < 0) {
 259                         log_error("Failed to inhibit: %s", bus_error_message(&error, fd));
 260                         return EXIT_FAILURE;
 261                 }
 262
 263                 r = safe_fork("(inhibit)", FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_CLOSE_ALL_FDS|FORK_LOG, &pid);
 264                 if (r < 0)
 265                         return EXIT_FAILURE;
 266                 if (r == 0) {
 267                         /* Child */
 268                         execvp(argv[optind], argv + optind);
 269                         log_open();
 270                         log_error_errno(errno, "Failed to execute %s: %m", argv[optind]);
 271                         _exit(EXIT_FAILURE);
 272                 }
 273
 274                 r = wait_for_terminate_and_check(argv[optind], pid, WAIT_LOG);
 275                 return r < 0 ? EXIT_FAILURE : r;
 276         }
 277
 278         return EXIT_SUCCESS;
 279 }