chiark / gitweb /
machine: make sure unpriviliged "machinectl status" can show the machine's OS version
[elogind.git] / src / login / inhibit.c
1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
2
3 /***
4   This file is part of systemd.
5
6   Copyright 2012 Lennart Poettering
7
8   systemd is free software; you can redistribute it and/or modify it
9   under the terms of the GNU Lesser General Public License as published by
10   the Free Software Foundation; either version 2.1 of the License, or
11   (at your option) any later version.
12
13   systemd is distributed in the hope that it will be useful, but
14   WITHOUT ANY WARRANTY; without even the implied warranty of
15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16   Lesser General Public License for more details.
17
18   You should have received a copy of the GNU Lesser General Public License
19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
20 ***/
21
22 #include <getopt.h>
23 #include <assert.h>
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <unistd.h>
27 #include <fcntl.h>
28
29 #include "sd-bus.h"
30 #include "bus-util.h"
31 #include "bus-error.h"
32 #include "util.h"
33 #include "build.h"
34 #include "strv.h"
35
36 static const char* arg_what = "idle:sleep:shutdown";
37 static const char* arg_who = NULL;
38 static const char* arg_why = "Unknown reason";
39 static const char* arg_mode = "block";
40
41 static enum {
42         ACTION_INHIBIT,
43         ACTION_LIST
44 } arg_action = ACTION_INHIBIT;
45
46 static int inhibit(sd_bus *bus, sd_bus_error *error) {
47         _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
48         int r;
49         int fd;
50
51         r = sd_bus_call_method(
52                         bus,
53                         "org.freedesktop.login1",
54                         "/org/freedesktop/login1",
55                         "org.freedesktop.login1.Manager",
56                         "Inhibit",
57                         error,
58                         &reply,
59                         "ssss", arg_what, arg_who, arg_why, arg_mode);
60         if (r < 0)
61                 return r;
62
63         r = sd_bus_message_read_basic(reply, SD_BUS_TYPE_UNIX_FD, &fd);
64         if (r < 0)
65                 return r;
66
67         r = fcntl(fd, F_DUPFD_CLOEXEC, 3);
68         if (r < 0)
69                 return -errno;
70
71         return r;
72 }
73
74 static int print_inhibitors(sd_bus *bus, sd_bus_error *error) {
75         _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
76         const char *what, *who, *why, *mode;
77         unsigned int uid, pid;
78         unsigned n = 0;
79         int r;
80
81         r = sd_bus_call_method(
82                         bus,
83                         "org.freedesktop.login1",
84                         "/org/freedesktop/login1",
85                         "org.freedesktop.login1.Manager",
86                         "ListInhibitors",
87                         error,
88                         &reply,
89                         "");
90         if (r < 0)
91                 return r;
92
93         r = sd_bus_message_enter_container(reply, SD_BUS_TYPE_ARRAY, "(ssssuu)");
94         if (r < 0)
95                 return bus_log_parse_error(r);
96
97         while ((r = sd_bus_message_read(reply, "(ssssuu)", &what, &who, &why, &mode, &uid, &pid)) > 0) {
98                 _cleanup_free_ char *comm = NULL, *u = NULL;
99
100                 get_process_comm(pid, &comm);
101                 u = uid_to_name(uid);
102
103                 printf("     Who: %s (UID "UID_FMT"/%s, PID "PID_FMT"/%s)\n"
104                        "    What: %s\n"
105                        "     Why: %s\n"
106                        "    Mode: %s\n\n",
107                        who, uid, strna(u), pid, strna(comm),
108                        what,
109                        why,
110                        mode);
111
112                 n++;
113         }
114         if (r < 0)
115                 return bus_log_parse_error(r);
116
117         r = sd_bus_message_exit_container(reply);
118         if (r < 0)
119                 return bus_log_parse_error(r);
120
121         printf("%u inhibitors listed.\n", n);
122         return 0;
123 }
124
125 static void help(void) {
126         printf("%s [OPTIONS...] {COMMAND} ...\n\n"
127                "Execute a process while inhibiting shutdown/sleep/idle.\n\n"
128                "  -h --help               Show this help\n"
129                "     --version            Show package version\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         };
151
152         static const struct option options[] = {
153                 { "help",         no_argument,       NULL, 'h'              },
154                 { "version",      no_argument,       NULL, ARG_VERSION      },
155                 { "what",         required_argument, NULL, ARG_WHAT         },
156                 { "who",          required_argument, NULL, ARG_WHO          },
157                 { "why",          required_argument, NULL, ARG_WHY          },
158                 { "mode",         required_argument, NULL, ARG_MODE         },
159                 { "list",         no_argument,       NULL, ARG_LIST         },
160                 {}
161         };
162
163         int c;
164
165         assert(argc >= 0);
166         assert(argv);
167
168         while ((c = getopt_long(argc, argv, "+h", options, NULL)) >= 0)
169
170                 switch (c) {
171
172                 case 'h':
173                         help();
174                         return 0;
175
176                 case ARG_VERSION:
177                         puts(PACKAGE_STRING);
178                         puts(SYSTEMD_FEATURES);
179                         return 0;
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 '?':
202                         return -EINVAL;
203
204                 default:
205                         assert_not_reached("Unhandled option");
206                 }
207
208         if (arg_action == ACTION_INHIBIT && argc == 1)
209                 arg_action = ACTION_LIST;
210
211         else if (arg_action == ACTION_INHIBIT && optind >= argc) {
212                 log_error("Missing command line to execute.");
213                 return -EINVAL;
214         }
215
216         return 1;
217 }
218
219 int main(int argc, char *argv[]) {
220         _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
221         _cleanup_bus_close_unref_ sd_bus *bus = NULL;
222         int r;
223
224         log_parse_environment();
225         log_open();
226
227         r = parse_argv(argc, argv);
228         if (r < 0)
229                 return EXIT_FAILURE;
230         if (r == 0)
231                 return EXIT_SUCCESS;
232
233         r = sd_bus_default_system(&bus);
234         if (r < 0) {
235                 log_error("Failed to connect to bus: %s", strerror(-r));
236                 return EXIT_FAILURE;
237         }
238
239         if (arg_action == ACTION_LIST) {
240
241                 r = print_inhibitors(bus, &error);
242                 if (r < 0) {
243                         log_error("Failed to list inhibitors: %s", bus_error_message(&error, -r));
244                         return EXIT_FAILURE;
245                 }
246
247         } else {
248                 _cleanup_close_ int fd = -1;
249                 _cleanup_free_ char *w = NULL;
250                 pid_t pid;
251
252                 if (!arg_who)
253                         arg_who = w = strv_join(argv + optind, " ");
254
255                 fd = inhibit(bus, &error);
256                 if (fd < 0) {
257                         log_error("Failed to inhibit: %s", bus_error_message(&error, -r));
258                         return EXIT_FAILURE;
259                 }
260
261                 pid = fork();
262                 if (pid < 0) {
263                         log_error("Failed to fork: %m");
264                         return EXIT_FAILURE;
265                 }
266
267                 if (pid == 0) {
268                         /* Child */
269
270                         close_all_fds(NULL, 0);
271
272                         execvp(argv[optind], argv + optind);
273                         log_error("Failed to execute %s: %m", argv[optind]);
274                         _exit(EXIT_FAILURE);
275                 }
276
277                 r = wait_for_terminate_and_warn(argv[optind], pid);
278                 return r < 0 ? EXIT_FAILURE : r;
279         }
280
281         return 0;
282 }