src/login/inhibit.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   Copyright 2012 Lennart Poettering
   4 ***/
   5
   6 #include <fcntl.h>
   7 #include <getopt.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <unistd.h>
  11
  12 #include "sd-bus.h"
  13
  14 #include "alloc-util.h"
  15 #include "bus-error.h"
  16 #include "bus-util.h"
  17 #include "fd-util.h"
  18 #include "format-util.h"
  19 //#include "pager.h"
  20 #include "process-util.h"
  21 #include "signal-util.h"
  22 #include "strv.h"
  23 #include "user-util.h"
  24 #include "util.h"
  25
  26 /// Additional includes needed by elogind
  27 #include "musl_missing.h"
  28
  29 static const char* arg_what = "idle:sleep:shutdown";
  30 static const char* arg_who = NULL;
  31 static const char* arg_why = "Unknown reason";
  32 static const char* arg_mode = NULL;
  33 static bool arg_no_pager = false;
  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         (void) pager_open(arg_no_pager, false);
  76
  77         r = sd_bus_call_method(
  78                         bus,
  79                         "org.freedesktop.login1",
  80                         "/org/freedesktop/login1",
  81                         "org.freedesktop.login1.Manager",
  82                         "ListInhibitors",
  83                         error,
  84                         &reply,
  85                         "");
  86         if (r < 0)
  87                 return r;
  88
  89         r = sd_bus_message_enter_container(reply, SD_BUS_TYPE_ARRAY, "(ssssuu)");
  90         if (r < 0)
  91                 return bus_log_parse_error(r);
  92
  93         while ((r = sd_bus_message_read(reply, "(ssssuu)", &what, &who, &why, &mode, &uid, &pid)) > 0) {
  94                 _cleanup_free_ char *comm = NULL, *u = NULL;
  95
  96                 if (arg_mode && !streq(mode, arg_mode))
  97                         continue;
  98
  99                 get_process_comm(pid, &comm);
 100                 u = uid_to_name(uid);
 101
 102                 printf("     Who: %s (UID "UID_FMT"/%s, PID "PID_FMT"/%s)\n"
 103                        "    What: %s\n"
 104                        "     Why: %s\n"
 105                        "    Mode: %s\n\n",
 106                        who, uid, strna(u), pid, strna(comm),
 107                        what,
 108                        why,
 109                        mode);
 110
 111                 n++;
 112         }
 113         if (r < 0)
 114                 return bus_log_parse_error(r);
 115
 116         r = sd_bus_message_exit_container(reply);
 117         if (r < 0)
 118                 return bus_log_parse_error(r);
 119
 120         printf("%u inhibitors listed.\n", n);
 121         return 0;
 122 }
 123
 124 static void help(void) {
 125         printf("%s [OPTIONS...] {COMMAND} ...\n\n"
 126                "Execute a process while inhibiting shutdown/sleep/idle.\n\n"
 127                "  -h --help               Show this help\n"
 128                "     --version            Show package version\n"
 129                "     --no-pager           Do not pipe output into a pager\n"
 130                "     --what=WHAT          Operations to inhibit, colon separated list of:\n"
 131                "                          shutdown, sleep, idle, handle-power-key,\n"
 132                "                          handle-suspend-key, handle-hibernate-key,\n"
 133                "                          handle-lid-switch\n"
 134                "     --who=STRING         A descriptive string who is inhibiting\n"
 135                "     --why=STRING         A descriptive string why is being inhibited\n"
 136                "     --mode=MODE          One of block or delay\n"
 137                "     --list               List active inhibitors\n"
 138                , program_invocation_short_name);
 139 }
 140
 141 static int parse_argv(int argc, char *argv[]) {
 142
 143         enum {
 144                 ARG_VERSION = 0x100,
 145                 ARG_WHAT,
 146                 ARG_WHO,
 147                 ARG_WHY,
 148                 ARG_MODE,
 149                 ARG_LIST,
 150                 ARG_NO_PAGER,
 151         };
 152
 153         static const struct option options[] = {
 154                 { "help",         no_argument,       NULL, 'h'              },
 155                 { "version",      no_argument,       NULL, ARG_VERSION      },
 156                 { "what",         required_argument, NULL, ARG_WHAT         },
 157                 { "who",          required_argument, NULL, ARG_WHO          },
 158                 { "why",          required_argument, NULL, ARG_WHY          },
 159                 { "mode",         required_argument, NULL, ARG_MODE         },
 160                 { "list",         no_argument,       NULL, ARG_LIST         },
 161                 { "no-pager",     no_argument,       NULL, ARG_NO_PAGER     },
 162                 {}
 163         };
 164
 165         int c;
 166
 167         assert(argc >= 0);
 168         assert(argv);
 169
 170         while ((c = getopt_long(argc, argv, "+h", options, NULL)) >= 0)
 171
 172                 switch (c) {
 173
 174                 case 'h':
 175                         help();
 176                         return 0;
 177
 178                 case ARG_VERSION:
 179                         return version();
 180
 181                 case ARG_WHAT:
 182                         arg_what = optarg;
 183                         break;
 184
 185                 case ARG_WHO:
 186                         arg_who = optarg;
 187                         break;
 188
 189                 case ARG_WHY:
 190                         arg_why = optarg;
 191                         break;
 192
 193                 case ARG_MODE:
 194                         arg_mode = optarg;
 195                         break;
 196
 197                 case ARG_LIST:
 198                         arg_action = ACTION_LIST;
 199                         break;
 200
 201                 case ARG_NO_PAGER:
 202                         arg_no_pager = true;
 203                         break;
 204
 205                 case '?':
 206                         return -EINVAL;
 207
 208                 default:
 209                         assert_not_reached("Unhandled option");
 210                 }
 211
 212         if (arg_action == ACTION_INHIBIT && optind == argc)
 213                 arg_action = ACTION_LIST;
 214
 215         else if (arg_action == ACTION_INHIBIT && optind >= argc) {
 216                 log_error("Missing command line to execute.");
 217                 return -EINVAL;
 218         }
 219
 220         return 1;
 221 }
 222
 223 int main(int argc, char *argv[]) {
 224         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 225         _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
 226         int r;
 227
 228         elogind_set_program_name(argv[0]);
 229         log_parse_environment();
 230         log_open();
 231
 232         r = parse_argv(argc, argv);
 233         if (r < 0)
 234                 return EXIT_FAILURE;
 235         if (r == 0)
 236                 return EXIT_SUCCESS;
 237
 238         r = sd_bus_default_system(&bus);
 239         if (r < 0) {
 240                 log_error_errno(r, "Failed to connect to bus: %m");
 241                 return EXIT_FAILURE;
 242         }
 243
 244         if (arg_action == ACTION_LIST) {
 245
 246                 r = print_inhibitors(bus, &error);
 247                 pager_close();
 248                 if (r < 0) {
 249                         log_error("Failed to list inhibitors: %s", bus_error_message(&error, -r));
 250                         return EXIT_FAILURE;
 251                 }
 252
 253         } else {
 254                 _cleanup_close_ int fd = -1;
 255                 _cleanup_free_ char *w = NULL;
 256                 pid_t pid;
 257
 258                 /* Ignore SIGINT and allow the forked process to receive it */
 259                 (void) ignore_signals(SIGINT, -1);
 260
 261                 if (!arg_who)
 262                         arg_who = w = strv_join(argv + optind, " ");
 263
 264                 if (!arg_mode)
 265                         arg_mode = "block";
 266
 267                 fd = inhibit(bus, &error);
 268                 if (fd < 0) {
 269                         log_error("Failed to inhibit: %s", bus_error_message(&error, fd));
 270                         return EXIT_FAILURE;
 271                 }
 272
 273                 r = safe_fork("(inhibit)", FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_CLOSE_ALL_FDS|FORK_LOG, &pid);
 274                 if (r < 0)
 275                         return EXIT_FAILURE;
 276                 if (r == 0) {
 277                         /* Child */
 278                         execvp(argv[optind], argv + optind);
 279                         log_open();
 280                         log_error_errno(errno, "Failed to execute %s: %m", argv[optind]);
 281                         _exit(EXIT_FAILURE);
 282                 }
 283
 284                 r = wait_for_terminate_and_check(argv[optind], pid, WAIT_LOG);
 285                 return r < 0 ? EXIT_FAILURE : r;
 286         }
 287
 288         return EXIT_SUCCESS;
 289 }