src/login/inhibit.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2012 Lennart Poettering
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <fcntl.h>
  21 #include <getopt.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <unistd.h>
  25
  26 #include "sd-bus.h"
  27
  28 #include "alloc-util.h"
  29 #include "bus-error.h"
  30 #include "bus-util.h"
  31 #include "fd-util.h"
  32 #include "format-util.h"
  33 #include "process-util.h"
  34 #include "signal-util.h"
  35 #include "strv.h"
  36 #include "user-util.h"
  37 #include "util.h"
  38
  39 /// Additional includes needed by elogind
  40 #include "musl_missing.h"
  41
  42 static const char* arg_what = "idle:sleep:shutdown";
  43 static const char* arg_who = NULL;
  44 static const char* arg_why = "Unknown reason";
  45 static const char* arg_mode = NULL;
  46
  47 static enum {
  48         ACTION_INHIBIT,
  49         ACTION_LIST
  50 } arg_action = ACTION_INHIBIT;
  51
  52 static int inhibit(sd_bus *bus, sd_bus_error *error) {
  53         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
  54         int r;
  55         int fd;
  56
  57         r = sd_bus_call_method(
  58                         bus,
  59                         "org.freedesktop.login1",
  60                         "/org/freedesktop/login1",
  61                         "org.freedesktop.login1.Manager",
  62                         "Inhibit",
  63                         error,
  64                         &reply,
  65                         "ssss", arg_what, arg_who, arg_why, arg_mode);
  66         if (r < 0)
  67                 return r;
  68
  69         r = sd_bus_message_read_basic(reply, SD_BUS_TYPE_UNIX_FD, &fd);
  70         if (r < 0)
  71                 return r;
  72
  73         r = fcntl(fd, F_DUPFD_CLOEXEC, 3);
  74         if (r < 0)
  75                 return -errno;
  76
  77         return r;
  78 }
  79
  80 static int print_inhibitors(sd_bus *bus, sd_bus_error *error) {
  81         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
  82         const char *what, *who, *why, *mode;
  83         unsigned int uid, pid;
  84         unsigned n = 0;
  85         int r;
  86
  87         r = sd_bus_call_method(
  88                         bus,
  89                         "org.freedesktop.login1",
  90                         "/org/freedesktop/login1",
  91                         "org.freedesktop.login1.Manager",
  92                         "ListInhibitors",
  93                         error,
  94                         &reply,
  95                         "");
  96         if (r < 0)
  97                 return r;
  98
  99         r = sd_bus_message_enter_container(reply, SD_BUS_TYPE_ARRAY, "(ssssuu)");
 100         if (r < 0)
 101                 return bus_log_parse_error(r);
 102
 103         while ((r = sd_bus_message_read(reply, "(ssssuu)", &what, &who, &why, &mode, &uid, &pid)) > 0) {
 104                 _cleanup_free_ char *comm = NULL, *u = NULL;
 105
 106                 if (arg_mode && !streq(mode, arg_mode))
 107                         continue;
 108
 109                 get_process_comm(pid, &comm);
 110                 u = uid_to_name(uid);
 111
 112                 printf("     Who: %s (UID "UID_FMT"/%s, PID "PID_FMT"/%s)\n"
 113                        "    What: %s\n"
 114                        "     Why: %s\n"
 115                        "    Mode: %s\n\n",
 116                        who, uid, strna(u), pid, strna(comm),
 117                        what,
 118                        why,
 119                        mode);
 120
 121                 n++;
 122         }
 123         if (r < 0)
 124                 return bus_log_parse_error(r);
 125
 126         r = sd_bus_message_exit_container(reply);
 127         if (r < 0)
 128                 return bus_log_parse_error(r);
 129
 130         printf("%u inhibitors listed.\n", n);
 131         return 0;
 132 }
 133
 134 static void help(void) {
 135         printf("%s [OPTIONS...] {COMMAND} ...\n\n"
 136                "Execute a process while inhibiting shutdown/sleep/idle.\n\n"
 137                "  -h --help               Show this help\n"
 138                "     --version            Show package version\n"
 139                "     --what=WHAT          Operations to inhibit, colon separated list of:\n"
 140                "                          shutdown, sleep, idle, handle-power-key,\n"
 141                "                          handle-suspend-key, handle-hibernate-key,\n"
 142                "                          handle-lid-switch\n"
 143                "     --who=STRING         A descriptive string who is inhibiting\n"
 144                "     --why=STRING         A descriptive string why is being inhibited\n"
 145                "     --mode=MODE          One of block or delay\n"
 146                "     --list               List active inhibitors\n"
 147                , program_invocation_short_name);
 148 }
 149
 150 static int parse_argv(int argc, char *argv[]) {
 151
 152         enum {
 153                 ARG_VERSION = 0x100,
 154                 ARG_WHAT,
 155                 ARG_WHO,
 156                 ARG_WHY,
 157                 ARG_MODE,
 158                 ARG_LIST,
 159         };
 160
 161         static const struct option options[] = {
 162                 { "help",         no_argument,       NULL, 'h'              },
 163                 { "version",      no_argument,       NULL, ARG_VERSION      },
 164                 { "what",         required_argument, NULL, ARG_WHAT         },
 165                 { "who",          required_argument, NULL, ARG_WHO          },
 166                 { "why",          required_argument, NULL, ARG_WHY          },
 167                 { "mode",         required_argument, NULL, ARG_MODE         },
 168                 { "list",         no_argument,       NULL, ARG_LIST         },
 169                 {}
 170         };
 171
 172         int c;
 173
 174         assert(argc >= 0);
 175         assert(argv);
 176
 177         while ((c = getopt_long(argc, argv, "+h", options, NULL)) >= 0)
 178
 179                 switch (c) {
 180
 181                 case 'h':
 182                         help();
 183                         return 0;
 184
 185                 case ARG_VERSION:
 186                         return version();
 187
 188                 case ARG_WHAT:
 189                         arg_what = optarg;
 190                         break;
 191
 192                 case ARG_WHO:
 193                         arg_who = optarg;
 194                         break;
 195
 196                 case ARG_WHY:
 197                         arg_why = optarg;
 198                         break;
 199
 200                 case ARG_MODE:
 201                         arg_mode = optarg;
 202                         break;
 203
 204                 case ARG_LIST:
 205                         arg_action = ACTION_LIST;
 206                         break;
 207
 208                 case '?':
 209                         return -EINVAL;
 210
 211                 default:
 212                         assert_not_reached("Unhandled option");
 213                 }
 214
 215         if (arg_action == ACTION_INHIBIT && optind == argc)
 216                 arg_action = ACTION_LIST;
 217
 218         else if (arg_action == ACTION_INHIBIT && optind >= argc) {
 219                 log_error("Missing command line to execute.");
 220                 return -EINVAL;
 221         }
 222
 223         return 1;
 224 }
 225
 226 int main(int argc, char *argv[]) {
 227         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 228         _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
 229         int r;
 230
 231         elogind_set_program_name(argv[0]);
 232         log_parse_environment();
 233         log_open();
 234
 235         r = parse_argv(argc, argv);
 236         if (r < 0)
 237                 return EXIT_FAILURE;
 238         if (r == 0)
 239                 return EXIT_SUCCESS;
 240
 241         r = sd_bus_default_system(&bus);
 242         if (r < 0) {
 243                 log_error_errno(r, "Failed to connect to bus: %m");
 244                 return EXIT_FAILURE;
 245         }
 246
 247         if (arg_action == ACTION_LIST) {
 248
 249                 r = print_inhibitors(bus, &error);
 250                 if (r < 0) {
 251                         log_error("Failed to list inhibitors: %s", bus_error_message(&error, -r));
 252                         return EXIT_FAILURE;
 253                 }
 254
 255         } else {
 256                 _cleanup_close_ int fd = -1;
 257                 _cleanup_free_ char *w = NULL;
 258                 pid_t pid;
 259
 260                 if (!arg_who)
 261                         arg_who = w = strv_join(argv + optind, " ");
 262
 263                 if (!arg_mode)
 264                         arg_mode = "block";
 265
 266                 fd = inhibit(bus, &error);
 267                 if (fd < 0) {
 268                         log_error("Failed to inhibit: %s", bus_error_message(&error, fd));
 269                         return EXIT_FAILURE;
 270                 }
 271
 272                 pid = fork();
 273                 if (pid < 0) {
 274                         log_error_errno(errno, "Failed to fork: %m");
 275                         return EXIT_FAILURE;
 276                 }
 277
 278                 if (pid == 0) {
 279                         /* Child */
 280
 281                         (void) reset_all_signal_handlers();
 282                         (void) reset_signal_mask();
 283
 284                         close_all_fds(NULL, 0);
 285
 286                         execvp(argv[optind], argv + optind);
 287                         log_error_errno(errno, "Failed to execute %s: %m", argv[optind]);
 288                         _exit(EXIT_FAILURE);
 289                 }
 290
 291                 r = wait_for_terminate_and_warn(argv[optind], pid, true);
 292                 return r < 0 ? EXIT_FAILURE : r;
 293         }
 294
 295         return 0;
 296 }