src/login/inhibit.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <fcntl.h>
   4 #include <getopt.h>
   5 #include <stdio.h>
   6 #include <unistd.h>
   7
   8 #include "sd-bus.h"
   9
  10 #include "alloc-util.h"
  11 #include "build.h"
  12 #include "bus-error.h"
  13 #include "bus-locator.h"
  14 #include "bus-util.h"
  15 #include "errno-util.h"
  16 #include "fd-util.h"
  17 #include "format-table.h"
  18 #include "log.h"
  19 #include "main-func.h"
  20 #include "pager.h"
  21 #include "polkit-agent.h"
  22 #include "pretty-print.h"
  23 #include "process-util.h"
  24 #include "runtime-scope.h"
  25 #include "signal-util.h"
  26 #include "string-util.h"
  27 #include "strv.h"
  28 #include "terminal-util.h"
  29 #include "user-util.h"
  30
  31 static const char *arg_what = "idle:sleep:shutdown";
  32 static const char *arg_who = NULL;
  33 static const char *arg_why = "Unknown reason";
  34 static const char *arg_mode = NULL;
  35 static bool arg_ask_password = true;
  36 static PagerFlags arg_pager_flags = 0;
  37 static bool arg_legend = true;
  38
  39 static enum {
  40         ACTION_INHIBIT,
  41         ACTION_LIST
  42 } arg_action = ACTION_INHIBIT;
  43
  44 static int inhibit(sd_bus *bus, sd_bus_error *error) {
  45         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
  46         int r;
  47         int fd;
  48
  49         (void) polkit_agent_open_if_enabled(BUS_TRANSPORT_LOCAL, arg_ask_password);
  50
  51         r = bus_call_method(bus, bus_login_mgr, "Inhibit", error, &reply, "ssss", arg_what, arg_who, arg_why, arg_mode);
  52         if (r < 0)
  53                 return r;
  54
  55         r = sd_bus_message_read_basic(reply, SD_BUS_TYPE_UNIX_FD, &fd);
  56         if (r < 0)
  57                 return r;
  58
  59         return RET_NERRNO(fcntl(fd, F_DUPFD_CLOEXEC, 3));
  60 }
  61
  62 static int print_inhibitors(sd_bus *bus) {
  63         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
  64         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
  65         _cleanup_(table_unrefp) Table *table = NULL;
  66         int r;
  67
  68         pager_open(arg_pager_flags);
  69
  70         r = bus_call_method(bus, bus_login_mgr, "ListInhibitors", &error, &reply, NULL);
  71         if (r < 0)
  72                 return log_error_errno(r, "Could not get active inhibitors: %s", bus_error_message(&error, r));
  73
  74         table = table_new("who", "uid", "user", "pid", "comm", "what", "why", "mode");
  75         if (!table)
  76                 return log_oom();
  77
  78         /* If there's not enough space, shorten the "WHY" column, as it's little more than an explaining comment. */
  79         (void) table_set_weight(table, TABLE_HEADER_CELL(6), 20);
  80         (void) table_set_maximum_width(table, TABLE_HEADER_CELL(0), columns()/2);
  81
  82         r = sd_bus_message_enter_container(reply, SD_BUS_TYPE_ARRAY, "(ssssuu)");
  83         if (r < 0)
  84                 return bus_log_parse_error(r);
  85
  86         for (;;) {
  87                 _cleanup_free_ char *comm = NULL, *u = NULL;
  88                 const char *what, *who, *why, *mode;
  89                 uint32_t uid, pid;
  90
  91                 r = sd_bus_message_read(reply, "(ssssuu)", &what, &who, &why, &mode, &uid, &pid);
  92                 if (r < 0)
  93                         return bus_log_parse_error(r);
  94                 if (r == 0)
  95                         break;
  96
  97                 if (arg_mode && !streq(mode, arg_mode))
  98                         continue;
  99
 100                 (void) pid_get_comm(pid, &comm);
 101                 u = uid_to_name(uid);
 102
 103                 r = table_add_many(table,
 104                                    TABLE_STRING, who,
 105                                    TABLE_UID, (uid_t) uid,
 106                                    TABLE_STRING, strna(u),
 107                                    TABLE_PID, (pid_t) pid,
 108                                    TABLE_STRING, strna(comm),
 109                                    TABLE_STRING, what,
 110                                    TABLE_STRING, why,
 111                                    TABLE_STRING, mode);
 112                 if (r < 0)
 113                         return table_log_add_error(r);
 114         }
 115
 116         r = sd_bus_message_exit_container(reply);
 117         if (r < 0)
 118                 return bus_log_parse_error(r);
 119
 120         if (!table_isempty(table)) {
 121                 r = table_set_sort(table, (size_t) 1, (size_t) 0, (size_t) 5, (size_t) 6);
 122                 if (r < 0)
 123                         return table_log_sort_error(r);
 124
 125                 table_set_header(table, arg_legend);
 126
 127                 r = table_print(table, NULL);
 128                 if (r < 0)
 129                         return table_log_print_error(r);
 130         }
 131
 132         if (arg_legend) {
 133                 if (table_isempty(table))
 134                         printf("No inhibitors.\n");
 135                 else
 136                         printf("\n%zu inhibitors listed.\n", table_get_rows(table) - 1);
 137         }
 138
 139         return 0;
 140 }
 141
 142 static int help(void) {
 143         _cleanup_free_ char *link = NULL;
 144         int r;
 145
 146         r = terminal_urlify_man("systemd-inhibit", "1", &link);
 147         if (r < 0)
 148                 return log_oom();
 149
 150         printf("%s [OPTIONS...] COMMAND ...\n"
 151                "\n%sExecute a process while inhibiting shutdown/sleep/idle.%s\n\n"
 152                "  -h --help               Show this help\n"
 153                "     --version            Show package version\n"
 154                "     --no-ask-password    Do not attempt interactive authorization\n"
 155                "     --no-pager           Do not pipe output into a pager\n"
 156                "     --no-legend          Do not show the headers and footers\n"
 157                "     --what=WHAT          Operations to inhibit, colon separated list of:\n"
 158                "                          shutdown, sleep, idle, handle-power-key,\n"
 159                "                          handle-suspend-key, handle-hibernate-key,\n"
 160                "                          handle-lid-switch\n"
 161                "     --who=STRING         A descriptive string who is inhibiting\n"
 162                "     --why=STRING         A descriptive string why is being inhibited\n"
 163                "     --mode=MODE          One of block, block-weak, or delay\n"
 164                "     --list               List active inhibitors\n"
 165                "\nSee the %s for details.\n",
 166                program_invocation_short_name,
 167                ansi_highlight(),
 168                ansi_normal(),
 169                link);
 170
 171         return 0;
 172 }
 173
 174 static int parse_argv(int argc, char *argv[]) {
 175
 176         enum {
 177                 ARG_VERSION = 0x100,
 178                 ARG_WHAT,
 179                 ARG_WHO,
 180                 ARG_WHY,
 181                 ARG_MODE,
 182                 ARG_LIST,
 183                 ARG_NO_ASK_PASSWORD,
 184                 ARG_NO_PAGER,
 185                 ARG_NO_LEGEND,
 186         };
 187
 188         static const struct option options[] = {
 189                 { "help",             no_argument,       NULL, 'h'                 },
 190                 { "version",          no_argument,       NULL, ARG_VERSION         },
 191                 { "no-ask-password",  no_argument,       NULL, ARG_NO_ASK_PASSWORD },
 192                 { "what",             required_argument, NULL, ARG_WHAT            },
 193                 { "who",              required_argument, NULL, ARG_WHO             },
 194                 { "why",              required_argument, NULL, ARG_WHY             },
 195                 { "mode",             required_argument, NULL, ARG_MODE            },
 196                 { "list",             no_argument,       NULL, ARG_LIST            },
 197                 { "no-pager",         no_argument,       NULL, ARG_NO_PAGER        },
 198                 { "no-legend",        no_argument,       NULL, ARG_NO_LEGEND       },
 199                 {}
 200         };
 201
 202         int c;
 203
 204         assert(argc >= 0);
 205         assert(argv);
 206
 207         /* Resetting to 0 forces the invocation of an internal initialization routine of getopt_long()
 208          * that checks for GNU extensions in optstring ('-' or '+' at the beginning). */
 209         optind = 0;
 210         while ((c = getopt_long(argc, argv, "+h", options, NULL)) >= 0)
 211
 212                 switch (c) {
 213
 214                 case 'h':
 215                         return help();
 216
 217                 case ARG_VERSION:
 218                         return version();
 219
 220                 case ARG_WHAT:
 221                         arg_what = optarg;
 222                         break;
 223
 224                 case ARG_WHO:
 225                         arg_who = optarg;
 226                         break;
 227
 228                 case ARG_WHY:
 229                         arg_why = optarg;
 230                         break;
 231
 232                 case ARG_MODE:
 233                         arg_mode = optarg;
 234                         break;
 235
 236                 case ARG_LIST:
 237                         arg_action = ACTION_LIST;
 238                         break;
 239
 240                 case ARG_NO_ASK_PASSWORD:
 241                         arg_ask_password = false;
 242                         break;
 243
 244                 case ARG_NO_PAGER:
 245                         arg_pager_flags |= PAGER_DISABLE;
 246                         break;
 247
 248                 case ARG_NO_LEGEND:
 249                         arg_legend = false;
 250                         break;
 251
 252                 case '?':
 253                         return -EINVAL;
 254
 255                 default:
 256                         assert_not_reached();
 257                 }
 258
 259         if (arg_action == ACTION_INHIBIT && optind == argc)
 260                 arg_action = ACTION_LIST;
 261
 262         else if (arg_action == ACTION_INHIBIT && optind >= argc)
 263                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 264                                        "Missing command line to execute.");
 265
 266         return 1;
 267 }
 268
 269 static int run(int argc, char *argv[]) {
 270         _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
 271         int r;
 272
 273         log_setup();
 274
 275         r = parse_argv(argc, argv);
 276         if (r <= 0)
 277                 return r;
 278
 279         r = sd_bus_default_system(&bus);
 280         if (r < 0)
 281                 return bus_log_connect_error(r, BUS_TRANSPORT_LOCAL, RUNTIME_SCOPE_SYSTEM);
 282
 283         (void) sd_bus_set_allow_interactive_authorization(bus, arg_ask_password);
 284
 285         if (arg_action == ACTION_LIST)
 286                 return print_inhibitors(bus);
 287         else {
 288                 _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 289                 _cleanup_strv_free_ char **arguments = NULL;
 290                 _cleanup_free_ char *w = NULL;
 291                 _cleanup_close_ int fd = -EBADF;
 292                 pid_t pid;
 293
 294                 /* Ignore SIGINT and allow the forked process to receive it */
 295                 (void) ignore_signals(SIGINT);
 296
 297                 if (!arg_who) {
 298                         w = strv_join(argv + optind, " ");
 299                         if (!w)
 300                                 return log_oom();
 301
 302                         arg_who = w;
 303                 }
 304
 305                 if (!arg_mode)
 306                         arg_mode = "block";
 307
 308                 fd = inhibit(bus, &error);
 309                 if (fd < 0)
 310                         return log_error_errno(fd, "Failed to inhibit: %s", bus_error_message(&error, fd));
 311
 312                 arguments = strv_copy(argv + optind);
 313                 if (!arguments)
 314                         return log_oom();
 315
 316                 r = safe_fork("(inhibit)", FORK_RESET_SIGNALS|FORK_DEATHSIG_SIGTERM|FORK_CLOSE_ALL_FDS|FORK_RLIMIT_NOFILE_SAFE|FORK_LOG, &pid);
 317                 if (r < 0)
 318                         return r;
 319                 if (r == 0) {
 320                         /* Child */
 321                         execvp(arguments[0], arguments);
 322                         log_open();
 323                         log_error_errno(errno, "Failed to execute %s: %m", argv[optind]);
 324                         _exit(EXIT_FAILURE);
 325                 }
 326
 327                 return wait_for_terminate_and_check(argv[optind], pid, WAIT_LOG);
 328         }
 329 }
 330
 331 DEFINE_MAIN_FUNCTION_WITH_POSITIVE_FAILURE(run);