src/login/inhibit.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <fcntl.h>
   4 #include <getopt.h>
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include <unistd.h>
   8
   9 #include "sd-bus.h"
  10
  11 #include "alloc-util.h"
  12 #include "bus-error.h"
  13 #include "bus-util.h"
  14 #include "fd-util.h"
  15 #include "format-util.h"
  16 #include "pager.h"
  17 #include "process-util.h"
  18 #include "signal-util.h"
  19 #include "strv.h"
  20 #include "user-util.h"
  21 #include "util.h"
  22
  23 /// Additional includes needed by elogind
  24 #include "musl_missing.h"
  25
  26 static const char* arg_what = "idle:sleep:shutdown";
  27 static const char* arg_who = NULL;
  28 static const char* arg_why = "Unknown reason";
  29 static const char* arg_mode = NULL;
  30 static bool arg_no_pager = false;
  31
  32 static enum {
  33         ACTION_INHIBIT,
  34         ACTION_LIST
  35 } arg_action = ACTION_INHIBIT;
  36
  37 static int inhibit(sd_bus *bus, sd_bus_error *error) {
  38         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
  39         int r;
  40         int fd;
  41
  42         r = sd_bus_call_method(
  43                         bus,
  44                         "org.freedesktop.login1",
  45                         "/org/freedesktop/login1",
  46                         "org.freedesktop.login1.Manager",
  47                         "Inhibit",
  48                         error,
  49                         &reply,
  50                         "ssss", arg_what, arg_who, arg_why, arg_mode);
  51         if (r < 0)
  52                 return r;
  53
  54         r = sd_bus_message_read_basic(reply, SD_BUS_TYPE_UNIX_FD, &fd);
  55         if (r < 0)
  56                 return r;
  57
  58         r = fcntl(fd, F_DUPFD_CLOEXEC, 3);
  59         if (r < 0)
  60                 return -errno;
  61
  62         return r;
  63 }
  64
  65 static int print_inhibitors(sd_bus *bus, sd_bus_error *error) {
  66         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
  67         const char *what, *who, *why, *mode;
  68         unsigned int uid, pid;
  69         unsigned n = 0;
  70         int r;
  71
  72         (void) pager_open(arg_no_pager, false);
  73
  74         r = sd_bus_call_method(
  75                         bus,
  76                         "org.freedesktop.login1",
  77                         "/org/freedesktop/login1",
  78                         "org.freedesktop.login1.Manager",
  79                         "ListInhibitors",
  80                         error,
  81                         &reply,
  82                         "");
  83         if (r < 0)
  84                 return r;
  85
  86         r = sd_bus_message_enter_container(reply, SD_BUS_TYPE_ARRAY, "(ssssuu)");
  87         if (r < 0)
  88                 return bus_log_parse_error(r);
  89
  90         while ((r = sd_bus_message_read(reply, "(ssssuu)", &what, &who, &why, &mode, &uid, &pid)) > 0) {
  91                 _cleanup_free_ char *comm = NULL, *u = NULL;
  92
  93                 if (arg_mode && !streq(mode, arg_mode))
  94                         continue;
  95
  96                 get_process_comm(pid, &comm);
  97                 u = uid_to_name(uid);
  98
  99                 printf("     Who: %s (UID "UID_FMT"/%s, PID "PID_FMT"/%s)\n"
 100                        "    What: %s\n"
 101                        "     Why: %s\n"
 102                        "    Mode: %s\n\n",
 103                        who, uid, strna(u), pid, strna(comm),
 104                        what,
 105                        why,
 106                        mode);
 107
 108                 n++;
 109         }
 110         if (r < 0)
 111                 return bus_log_parse_error(r);
 112
 113         r = sd_bus_message_exit_container(reply);
 114         if (r < 0)
 115                 return bus_log_parse_error(r);
 116
 117         printf("%u inhibitors listed.\n", n);
 118         return 0;
 119 }
 120
 121 static void help(void) {
 122         printf("%s [OPTIONS...] {COMMAND} ...\n\n"
 123                "Execute a process while inhibiting shutdown/sleep/idle.\n\n"
 124                "  -h --help               Show this help\n"
 125                "     --version            Show package version\n"
 126                "     --no-pager           Do not pipe output into a pager\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                 ARG_NO_PAGER,
 148         };
 149
 150         static const struct option options[] = {
 151                 { "help",         no_argument,       NULL, 'h'              },
 152                 { "version",      no_argument,       NULL, ARG_VERSION      },
 153                 { "what",         required_argument, NULL, ARG_WHAT         },
 154                 { "who",          required_argument, NULL, ARG_WHO          },
 155                 { "why",          required_argument, NULL, ARG_WHY          },
 156                 { "mode",         required_argument, NULL, ARG_MODE         },
 157                 { "list",         no_argument,       NULL, ARG_LIST         },
 158                 { "no-pager",     no_argument,       NULL, ARG_NO_PAGER     },
 159                 {}
 160         };
 161
 162         int c;
 163
 164         assert(argc >= 0);
 165         assert(argv);
 166
 167         while ((c = getopt_long(argc, argv, "+h", options, NULL)) >= 0)
 168
 169                 switch (c) {
 170
 171                 case 'h':
 172                         help();
 173                         return 0;
 174
 175                 case ARG_VERSION:
 176                         return version();
 177
 178                 case ARG_WHAT:
 179                         arg_what = optarg;
 180                         break;
 181
 182                 case ARG_WHO:
 183                         arg_who = optarg;
 184                         break;
 185
 186                 case ARG_WHY:
 187                         arg_why = optarg;
 188                         break;
 189
 190                 case ARG_MODE:
 191                         arg_mode = optarg;
 192                         break;
 193
 194                 case ARG_LIST:
 195                         arg_action = ACTION_LIST;
 196                         break;
 197
 198                 case ARG_NO_PAGER:
 199                         arg_no_pager = true;
 200                         break;
 201
 202                 case '?':
 203                         return -EINVAL;
 204
 205                 default:
 206                         assert_not_reached("Unhandled option");
 207                 }
 208
 209         if (arg_action == ACTION_INHIBIT && optind == argc)
 210                 arg_action = ACTION_LIST;
 211
 212         else if (arg_action == ACTION_INHIBIT && optind >= argc) {
 213                 log_error("Missing command line to execute.");
 214                 return -EINVAL;
 215         }
 216
 217         return 1;
 218 }
 219
 220 int main(int argc, char *argv[]) {
 221         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 222         _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
 223         int r;
 224
 225         elogind_set_program_name(argv[0]);
 226         log_parse_environment();
 227         log_open();
 228
 229         r = parse_argv(argc, argv);
 230         if (r < 0)
 231                 return EXIT_FAILURE;
 232         if (r == 0)
 233                 return EXIT_SUCCESS;
 234
 235         r = sd_bus_default_system(&bus);
 236         if (r < 0) {
 237                 log_error_errno(r, "Failed to connect to bus: %m");
 238                 return EXIT_FAILURE;
 239         }
 240
 241         if (arg_action == ACTION_LIST) {
 242
 243                 r = print_inhibitors(bus, &error);
 244                 pager_close();
 245                 if (r < 0) {
 246                         log_error("Failed to list inhibitors: %s", bus_error_message(&error, -r));
 247                         return EXIT_FAILURE;
 248                 }
 249
 250         } else {
 251                 _cleanup_close_ int fd = -1;
 252                 _cleanup_free_ char *w = NULL;
 253                 pid_t pid;
 254
 255                 /* Ignore SIGINT and allow the forked process to receive it */
 256                 (void) ignore_signals(SIGINT, -1);
 257
 258                 if (!arg_who)
 259                         arg_who = w = strv_join(argv + optind, " ");
 260
 261                 if (!arg_mode)
 262                         arg_mode = "block";
 263
 264                 fd = inhibit(bus, &error);
 265                 if (fd < 0) {
 266                         log_error("Failed to inhibit: %s", bus_error_message(&error, fd));
 267                         return EXIT_FAILURE;
 268                 }
 269
 270                 r = safe_fork("(inhibit)", FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_CLOSE_ALL_FDS|FORK_LOG, &pid);
 271                 if (r < 0)
 272                         return EXIT_FAILURE;
 273                 if (r == 0) {
 274                         /* Child */
 275                         execvp(argv[optind], argv + optind);
 276                         log_open();
 277                         log_error_errno(errno, "Failed to execute %s: %m", argv[optind]);
 278                         _exit(EXIT_FAILURE);
 279                 }
 280
 281                 r = wait_for_terminate_and_check(argv[optind], pid, WAIT_LOG);
 282                 return r < 0 ? EXIT_FAILURE : r;
 283         }
 284
 285         return EXIT_SUCCESS;
 286 }