1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * This program is free software: you can redistribute it and/or modify
4  * it under the terms of the GNU General Public License as published by
5  * the Free Software Foundation, either version 2 of the License, or
6  * (at your option) any later version.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  */
13 
14 #include <errno.h>
15 #include <getopt.h>
16 #include <stddef.h>
17 #include <stdio.h>
18 #include <stdlib.h>
19 #include <string.h>
20 #include <unistd.h>
21 
22 #include "parse-util.h"
23 #include "process-util.h"
24 #include "syslog-util.h"
25 #include "time-util.h"
26 #include "udevadm.h"
27 #include "udev-ctrl.h"
28 #include "util.h"
29 #include "virt.h"
30 
help(void)31 static int help(void) {
32         printf("%s control OPTION\n\n"
33                "Control the udev daemon.\n\n"
34                "  -h --help                Show this help\n"
35                "  -V --version             Show package version\n"
36                "  -e --exit                Instruct the daemon to cleanup and exit\n"
37                "  -l --log-level=LEVEL     Set the udev log level for the daemon\n"
38                "  -s --stop-exec-queue     Do not execute events, queue only\n"
39                "  -S --start-exec-queue    Execute events, flush queue\n"
40                "  -R --reload              Reload rules and databases\n"
41                "  -p --property=KEY=VALUE  Set a global property for all events\n"
42                "  -m --children-max=N      Maximum number of children\n"
43                "     --ping                Wait for udev to respond to a ping message\n"
44                "  -t --timeout=SECONDS     Maximum time to block for a reply\n",
45                program_invocation_short_name);
46 
47         return 0;
48 }
49 
control_main(int argc,char * argv[],void * userdata)50 int control_main(int argc, char *argv[], void *userdata) {
51         _cleanup_(udev_ctrl_unrefp) UdevCtrl *uctrl = NULL;
52         usec_t timeout = 60 * USEC_PER_SEC;
53         int c, r;
54 
55         enum {
56                 ARG_PING = 0x100,
57         };
58 
59         static const struct option options[] = {
60                 { "exit",             no_argument,       NULL, 'e'      },
61                 { "log-level",        required_argument, NULL, 'l'      },
62                 { "log-priority",     required_argument, NULL, 'l'      }, /* for backward compatibility */
63                 { "stop-exec-queue",  no_argument,       NULL, 's'      },
64                 { "start-exec-queue", no_argument,       NULL, 'S'      },
65                 { "reload",           no_argument,       NULL, 'R'      },
66                 { "reload-rules",     no_argument,       NULL, 'R'      }, /* alias for -R */
67                 { "property",         required_argument, NULL, 'p'      },
68                 { "env",              required_argument, NULL, 'p'      }, /* alias for -p */
69                 { "children-max",     required_argument, NULL, 'm'      },
70                 { "ping",             no_argument,       NULL, ARG_PING },
71                 { "timeout",          required_argument, NULL, 't'      },
72                 { "version",          no_argument,       NULL, 'V'      },
73                 { "help",             no_argument,       NULL, 'h'      },
74                 {}
75         };
76 
77         if (running_in_chroot() > 0) {
78                 log_info("Running in chroot, ignoring request.");
79                 return 0;
80         }
81 
82         if (argc <= 1)
83                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
84                                        "This command expects one or more options.");
85 
86         r = udev_ctrl_new(&uctrl);
87         if (r < 0)
88                 return log_error_errno(r, "Failed to initialize udev control: %m");
89 
90         while ((c = getopt_long(argc, argv, "el:sSRp:m:t:Vh", options, NULL)) >= 0)
91                 switch (c) {
92                 case 'e':
93                         r = udev_ctrl_send_exit(uctrl);
94                         if (r == -ENOANO)
95                                 log_warning("Cannot specify --exit after --exit, ignoring.");
96                         else if (r < 0)
97                                 return log_error_errno(r, "Failed to send exit request: %m");
98                         break;
99                 case 'l':
100                         r = log_level_from_string(optarg);
101                         if (r < 0)
102                                 return log_error_errno(r, "Failed to parse log level '%s': %m", optarg);
103 
104                         r = udev_ctrl_send_set_log_level(uctrl, r);
105                         if (r == -ENOANO)
106                                 log_warning("Cannot specify --log-level after --exit, ignoring.");
107                         else if (r < 0)
108                                 return log_error_errno(r, "Failed to send request to set log level: %m");
109                         break;
110                 case 's':
111                         r = udev_ctrl_send_stop_exec_queue(uctrl);
112                         if (r == -ENOANO)
113                                 log_warning("Cannot specify --stop-exec-queue after --exit, ignoring.");
114                         else if (r < 0)
115                                 return log_error_errno(r, "Failed to send request to stop exec queue: %m");
116                         break;
117                 case 'S':
118                         r = udev_ctrl_send_start_exec_queue(uctrl);
119                         if (r == -ENOANO)
120                                 log_warning("Cannot specify --start-exec-queue after --exit, ignoring.");
121                         else if (r < 0)
122                                 return log_error_errno(r, "Failed to send request to start exec queue: %m");
123                         break;
124                 case 'R':
125                         r = udev_ctrl_send_reload(uctrl);
126                         if (r == -ENOANO)
127                                 log_warning("Cannot specify --reload after --exit, ignoring.");
128                         else if (r < 0)
129                                 return log_error_errno(r, "Failed to send reload request: %m");
130                         break;
131                 case 'p':
132                         if (!strchr(optarg, '='))
133                                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "expect <KEY>=<value> instead of '%s'", optarg);
134 
135                         r = udev_ctrl_send_set_env(uctrl, optarg);
136                         if (r == -ENOANO)
137                                 log_warning("Cannot specify --property after --exit, ignoring.");
138                         else if (r < 0)
139                                 return log_error_errno(r, "Failed to send request to update environment: %m");
140                         break;
141                 case 'm': {
142                         unsigned i;
143 
144                         r = safe_atou(optarg, &i);
145                         if (r < 0)
146                                 return log_error_errno(r, "Failed to parse maximum number of events '%s': %m", optarg);
147 
148                         r = udev_ctrl_send_set_children_max(uctrl, i);
149                         if (r == -ENOANO)
150                                 log_warning("Cannot specify --children-max after --exit, ignoring.");
151                         else if (r < 0)
152                                 return log_error_errno(r, "Failed to send request to set number of children: %m");
153                         break;
154                 }
155                 case ARG_PING:
156                         r = udev_ctrl_send_ping(uctrl);
157                         if (r == -ENOANO)
158                                 log_error("Cannot specify --ping after --exit, ignoring.");
159                         else if (r < 0)
160                                 return log_error_errno(r, "Failed to send a ping message: %m");
161                         break;
162                 case 't':
163                         r = parse_sec(optarg, &timeout);
164                         if (r < 0)
165                                 return log_error_errno(r, "Failed to parse timeout value '%s': %m", optarg);
166                         break;
167                 case 'V':
168                         return print_version();
169                 case 'h':
170                         return help();
171                 case '?':
172                         return -EINVAL;
173                 default:
174                         assert_not_reached();
175                 }
176 
177         if (optind < argc)
178                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
179                                        "Extraneous argument: %s", argv[optind]);
180 
181         r = udev_ctrl_wait(uctrl, timeout);
182         if (r < 0)
183                 return log_error_errno(r, "Failed to wait for daemon to reply: %m");
184 
185         return 0;
186 }
187