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-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
  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-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("Unknown option.");
 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 }