src/udev/udevadm-control.c

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   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
  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-priority=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
  50 int control_main(int argc, char *argv[], void *userdata) {
  51         _cleanup_(udev_ctrl_unrefp) struct udev_ctrl *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-priority",     required_argument, NULL, 'l'      },
  62                 { "stop-exec-queue",  no_argument,       NULL, 's'      },
  63                 { "start-exec-queue", no_argument,       NULL, 'S'      },
  64                 { "reload",           no_argument,       NULL, 'R'      },
  65                 { "reload-rules",     no_argument,       NULL, 'R'      }, /* alias for -R */
  66                 { "property",         required_argument, NULL, 'p'      },
  67                 { "env",              required_argument, NULL, 'p'      }, /* alias for -p */
  68                 { "children-max",     required_argument, NULL, 'm'      },
  69                 { "ping",             no_argument,       NULL, ARG_PING },
  70                 { "timeout",          required_argument, NULL, 't'      },
  71                 { "version",          no_argument,       NULL, 'V'      },
  72                 { "help",             no_argument,       NULL, 'h'      },
  73                 {}
  74         };
  75
  76         if (running_in_chroot() > 0) {
  77                 log_info("Running in chroot, ignoring request.");
  78                 return 0;
  79         }
  80
  81         if (argc <= 1)
  82                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
  83                                        "This command expects one or more options.");
  84
  85         r = udev_ctrl_new(&uctrl);
  86         if (r < 0)
  87                 return log_error_errno(r, "Failed to initialize udev control: %m");
  88
  89         while ((c = getopt_long(argc, argv, "el:sSRp:m:t:Vh", options, NULL)) >= 0)
  90                 switch (c) {
  91                 case 'e':
  92                         r = udev_ctrl_send_exit(uctrl);
  93                         if (r == -ENOANO)
  94                                 log_warning("Cannot specify --exit after --exit, ignoring.");
  95                         else if (r < 0)
  96                                 return log_error_errno(r, "Failed to send exit request: %m");
  97                         break;
  98                 case 'l':
  99                         r = log_level_from_string(optarg);
 100                         if (r < 0)
 101                                 return log_error_errno(r, "Failed to parse log priority '%s': %m", optarg);
 102
 103                         r = udev_ctrl_send_set_log_level(uctrl, r);
 104                         if (r == -ENOANO)
 105                                 log_warning("Cannot specify --log-priority after --exit, ignoring.");
 106                         else if (r < 0)
 107                                 return log_error_errno(r, "Failed to send request to set log level: %m");
 108                         break;
 109                 case 's':
 110                         r = udev_ctrl_send_stop_exec_queue(uctrl);
 111                         if (r == -ENOANO)
 112                                 log_warning("Cannot specify --stop-exec-queue after --exit, ignoring.");
 113                         else if (r < 0)
 114                                 return log_error_errno(r, "Failed to send request to stop exec queue: %m");
 115                         break;
 116                 case 'S':
 117                         r = udev_ctrl_send_start_exec_queue(uctrl);
 118                         if (r == -ENOANO)
 119                                 log_warning("Cannot specify --start-exec-queue after --exit, ignoring.");
 120                         else if (r < 0)
 121                                 return log_error_errno(r, "Failed to send request to start exec queue: %m");
 122                         break;
 123                 case 'R':
 124                         r = udev_ctrl_send_reload(uctrl);
 125                         if (r == -ENOANO)
 126                                 log_warning("Cannot specify --reload after --exit, ignoring.");
 127                         else if (r < 0)
 128                                 return log_error_errno(r, "Failed to send reload request: %m");
 129                         break;
 130                 case 'p':
 131                         if (!strchr(optarg, '='))
 132                                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "expect <KEY>=<value> instead of '%s'", optarg);
 133
 134                         r = udev_ctrl_send_set_env(uctrl, optarg);
 135                         if (r == -ENOANO)
 136                                 log_warning("Cannot specify --property after --exit, ignoring.");
 137                         else if (r < 0)
 138                                 return log_error_errno(r, "Failed to send request to update environment: %m");
 139                         break;
 140                 case 'm': {
 141                         unsigned i;
 142
 143                         r = safe_atou(optarg, &i);
 144                         if (r < 0)
 145                                 return log_error_errno(r, "Failed to parse maximum number of events '%s': %m", optarg);
 146
 147                         r = udev_ctrl_send_set_children_max(uctrl, i);
 148                         if (r == -ENOANO)
 149                                 log_warning("Cannot specify --children-max after --exit, ignoring.");
 150                         else if (r < 0)
 151                                 return log_error_errno(r, "Failed to send request to set number of children: %m");
 152                         break;
 153                 }
 154                 case ARG_PING:
 155                         r = udev_ctrl_send_ping(uctrl);
 156                         if (r == -ENOANO)
 157                                 log_error("Cannot specify --ping after --exit, ignoring.");
 158                         else if (r < 0)
 159                                 return log_error_errno(r, "Failed to send a ping message: %m");
 160                         break;
 161                 case 't':
 162                         r = parse_sec(optarg, &timeout);
 163                         if (r < 0)
 164                                 return log_error_errno(r, "Failed to parse timeout value '%s': %m", optarg);
 165                         break;
 166                 case 'V':
 167                         return print_version();
 168                 case 'h':
 169                         return help();
 170                 case '?':
 171                         return -EINVAL;
 172                 default:
 173                         assert_not_reached("Unknown option.");
 174                 }
 175
 176         if (optind < argc)
 177                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 178                                        "Extraneous argument: %s", argv[optind]);
 179
 180         r = udev_ctrl_wait(uctrl, timeout);
 181         if (r < 0)
 182                 return log_error_errno(r, "Failed to wait for daemon to reply: %m");
 183
 184         return 0;
 185 }