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