src/udev/udevadm-trigger.c

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2
   3 #include <errno.h>
   4 #include <getopt.h>
   5
   6 #include "sd-device.h"
   7 #include "sd-event.h"
   8
   9 #include "device-enumerator-private.h"
  10 #include "device-private.h"
  11 #include "fd-util.h"
  12 #include "fileio.h"
  13 #include "path-util.h"
  14 #include "process-util.h"
  15 #include "set.h"
  16 #include "string-util.h"
  17 #include "strv.h"
  18 #include "udevadm.h"
  19 #include "udevadm-util.h"
  20 #include "udev-ctrl.h"
  21 #include "virt.h"
  22
  23 static bool arg_verbose = false;
  24 static bool arg_dry_run = false;
  25
  26 static int exec_list(sd_device_enumerator *e, const char *action, Set *settle_set) {
  27         sd_device *d;
  28         int r;
  29
  30         FOREACH_DEVICE_AND_SUBSYSTEM(e, d) {
  31                 _cleanup_free_ char *filename = NULL;
  32                 const char *syspath;
  33
  34                 if (sd_device_get_syspath(d, &syspath) < 0)
  35                         continue;
  36
  37                 if (arg_verbose)
  38                         printf("%s\n", syspath);
  39                 if (arg_dry_run)
  40                         continue;
  41
  42                 filename = path_join(syspath, "uevent");
  43                 if (!filename)
  44                         return log_oom();
  45
  46                 r = write_string_file(filename, action, WRITE_STRING_FILE_DISABLE_BUFFER);
  47                 if (r < 0) {
  48                         log_debug_errno(r, "Failed to write '%s' to '%s', ignoring: %m", action, filename);
  49                         continue;
  50                 }
  51
  52                 if (settle_set) {
  53                         r = set_put_strdup(settle_set, syspath);
  54                         if (r < 0)
  55                                 return log_oom();
  56                 }
  57         }
  58
  59         return 0;
  60 }
  61
  62 static int device_monitor_handler(sd_device_monitor *m, sd_device *dev, void *userdata) {
  63         _cleanup_free_ char *val = NULL;
  64         Set *settle_set = userdata;
  65         const char *syspath;
  66
  67         assert(dev);
  68         assert(settle_set);
  69
  70         if (sd_device_get_syspath(dev, &syspath) < 0)
  71                 return 0;
  72
  73         if (arg_verbose)
  74                 printf("settle %s\n", syspath);
  75
  76         val = set_remove(settle_set, syspath);
  77         if (!val)
  78                 log_debug("Got epoll event on syspath %s not present in syspath set", syspath);
  79
  80         if (set_isempty(settle_set))
  81                 return sd_event_exit(sd_device_monitor_get_event(m), 0);
  82
  83         return 0;
  84 }
  85
  86 static char* keyval(const char *str, const char **key, const char **val) {
  87         char *buf, *pos;
  88
  89         buf = strdup(str);
  90         if (!buf)
  91                 return NULL;
  92
  93         pos = strchr(buf, '=');
  94         if (pos) {
  95                 pos[0] = 0;
  96                 pos++;
  97         }
  98
  99         *key = buf;
 100         *val = pos;
 101
 102         return buf;
 103 }
 104
 105 static int help(void) {
 106         printf("%s trigger [OPTIONS] DEVPATH\n\n"
 107                "Request events from the kernel.\n\n"
 108                "  -h --help                         Show this help\n"
 109                "  -V --version                      Show package version\n"
 110                "  -v --verbose                      Print the list of devices while running\n"
 111                "  -n --dry-run                      Do not actually trigger the events\n"
 112                "  -t --type=                        Type of events to trigger\n"
 113                "          devices                     sysfs devices (default)\n"
 114                "          subsystems                  sysfs subsystems and drivers\n"
 115                "  -c --action=ACTION                Event action value, default is \"change\"\n"
 116                "  -s --subsystem-match=SUBSYSTEM    Trigger devices from a matching subsystem\n"
 117                "  -S --subsystem-nomatch=SUBSYSTEM  Exclude devices from a matching subsystem\n"
 118                "  -a --attr-match=FILE[=VALUE]      Trigger devices with a matching attribute\n"
 119                "  -A --attr-nomatch=FILE[=VALUE]    Exclude devices with a matching attribute\n"
 120                "  -p --property-match=KEY=VALUE     Trigger devices with a matching property\n"
 121                "  -g --tag-match=KEY=VALUE          Trigger devices with a matching property\n"
 122                "  -y --sysname-match=NAME           Trigger devices with this /sys path\n"
 123                "     --name-match=NAME              Trigger devices with this /dev name\n"
 124                "  -b --parent-match=NAME            Trigger devices with that parent device\n"
 125                "  -w --settle                       Wait for the triggered events to complete\n"
 126                "     --wait-daemon[=SECONDS]        Wait for udevd daemon to be initialized\n"
 127                "                                    before triggering uevents\n"
 128                , program_invocation_short_name);
 129
 130         return 0;
 131 }
 132
 133 int trigger_main(int argc, char *argv[], void *userdata) {
 134         enum {
 135                 ARG_NAME = 0x100,
 136                 ARG_PING,
 137         };
 138
 139         static const struct option options[] = {
 140                 { "verbose",           no_argument,       NULL, 'v'      },
 141                 { "dry-run",           no_argument,       NULL, 'n'      },
 142                 { "type",              required_argument, NULL, 't'      },
 143                 { "action",            required_argument, NULL, 'c'      },
 144                 { "subsystem-match",   required_argument, NULL, 's'      },
 145                 { "subsystem-nomatch", required_argument, NULL, 'S'      },
 146                 { "attr-match",        required_argument, NULL, 'a'      },
 147                 { "attr-nomatch",      required_argument, NULL, 'A'      },
 148                 { "property-match",    required_argument, NULL, 'p'      },
 149                 { "tag-match",         required_argument, NULL, 'g'      },
 150                 { "sysname-match",     required_argument, NULL, 'y'      },
 151                 { "name-match",        required_argument, NULL, ARG_NAME },
 152                 { "parent-match",      required_argument, NULL, 'b'      },
 153                 { "settle",            no_argument,       NULL, 'w'      },
 154                 { "wait-daemon",       optional_argument, NULL, ARG_PING },
 155                 { "version",           no_argument,       NULL, 'V'      },
 156                 { "help",              no_argument,       NULL, 'h'      },
 157                 {}
 158         };
 159         enum {
 160                 TYPE_DEVICES,
 161                 TYPE_SUBSYSTEMS,
 162         } device_type = TYPE_DEVICES;
 163         const char *action = "change";
 164         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
 165         _cleanup_(sd_device_monitor_unrefp) sd_device_monitor *m = NULL;
 166         _cleanup_(sd_event_unrefp) sd_event *event = NULL;
 167         _cleanup_set_free_free_ Set *settle_set = NULL;
 168         usec_t ping_timeout_usec = 5 * USEC_PER_SEC;
 169         bool settle = false, ping = false;
 170         int c, r;
 171
 172         if (running_in_chroot() > 0) {
 173                 log_info("Running in chroot, ignoring request.");
 174                 return 0;
 175         }
 176
 177         r = sd_device_enumerator_new(&e);
 178         if (r < 0)
 179                 return r;
 180
 181         r = sd_device_enumerator_allow_uninitialized(e);
 182         if (r < 0)
 183                 return r;
 184
 185         while ((c = getopt_long(argc, argv, "vnt:c:s:S:a:A:p:g:y:b:wVh", options, NULL)) >= 0) {
 186                 _cleanup_free_ char *buf = NULL;
 187                 const char *key, *val;
 188
 189                 switch (c) {
 190                 case 'v':
 191                         arg_verbose = true;
 192                         break;
 193                 case 'n':
 194                         arg_dry_run = true;
 195                         break;
 196                 case 't':
 197                         if (streq(optarg, "devices"))
 198                                 device_type = TYPE_DEVICES;
 199                         else if (streq(optarg, "subsystems"))
 200                                 device_type = TYPE_SUBSYSTEMS;
 201                         else
 202                                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Unknown type --type=%s", optarg);
 203                         break;
 204                 case 'c':
 205                         if (device_action_from_string(optarg) < 0)
 206                                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Unknown action '%s'", optarg);
 207
 208                         action = optarg;
 209                         break;
 210                 case 's':
 211                         r = sd_device_enumerator_add_match_subsystem(e, optarg, true);
 212                         if (r < 0)
 213                                 return log_error_errno(r, "Failed to add subsystem match '%s': %m", optarg);
 214                         break;
 215                 case 'S':
 216                         r = sd_device_enumerator_add_match_subsystem(e, optarg, false);
 217                         if (r < 0)
 218                                 return log_error_errno(r, "Failed to add negative subsystem match '%s': %m", optarg);
 219                         break;
 220                 case 'a':
 221                         buf = keyval(optarg, &key, &val);
 222                         if (!buf)
 223                                 return log_oom();
 224                         r = sd_device_enumerator_add_match_sysattr(e, key, val, true);
 225                         if (r < 0)
 226                                 return log_error_errno(r, "Failed to add sysattr match '%s=%s': %m", key, val);
 227                         break;
 228                 case 'A':
 229                         buf = keyval(optarg, &key, &val);
 230                         if (!buf)
 231                                 return log_oom();
 232                         r = sd_device_enumerator_add_match_sysattr(e, key, val, false);
 233                         if (r < 0)
 234                                 return log_error_errno(r, "Failed to add negative sysattr match '%s=%s': %m", key, val);
 235                         break;
 236                 case 'p':
 237                         buf = keyval(optarg, &key, &val);
 238                         if (!buf)
 239                                 return log_oom();
 240                         r = sd_device_enumerator_add_match_property(e, key, val);
 241                         if (r < 0)
 242                                 return log_error_errno(r, "Failed to add property match '%s=%s': %m", key, val);
 243                         break;
 244                 case 'g':
 245                         r = sd_device_enumerator_add_match_tag(e, optarg);
 246                         if (r < 0)
 247                                 return log_error_errno(r, "Failed to add tag match '%s': %m", optarg);
 248                         break;
 249                 case 'y':
 250                         r = sd_device_enumerator_add_match_sysname(e, optarg);
 251                         if (r < 0)
 252                                 return log_error_errno(r, "Failed to add sysname match '%s': %m", optarg);
 253                         break;
 254                 case 'b': {
 255                         _cleanup_(sd_device_unrefp) sd_device *dev = NULL;
 256
 257                         r = find_device(optarg, "/sys", &dev);
 258                         if (r < 0)
 259                                 return log_error_errno(r, "Failed to open the device '%s': %m", optarg);
 260
 261                         r = device_enumerator_add_match_parent_incremental(e, dev);
 262                         if (r < 0)
 263                                 return log_error_errno(r, "Failed to add parent match '%s': %m", optarg);
 264                         break;
 265                 }
 266                 case 'w':
 267                         settle = true;
 268                         break;
 269
 270                 case ARG_NAME: {
 271                         _cleanup_(sd_device_unrefp) sd_device *dev = NULL;
 272
 273                         r = find_device(optarg, "/dev/", &dev);
 274                         if (r < 0)
 275                                 return log_error_errno(r, "Failed to open the device '%s': %m", optarg);
 276
 277                         r = device_enumerator_add_match_parent_incremental(e, dev);
 278                         if (r < 0)
 279                                 return log_error_errno(r, "Failed to add parent match '%s': %m", optarg);
 280                         break;
 281                 }
 282
 283                 case ARG_PING: {
 284                         ping = true;
 285                         if (optarg) {
 286                                 r = parse_sec(optarg, &ping_timeout_usec);
 287                                 if (r < 0)
 288                                         log_error_errno(r, "Failed to parse timeout value '%s', ignoring: %m", optarg);
 289                         }
 290                         break;
 291                 }
 292
 293                 case 'V':
 294                         return print_version();
 295                 case 'h':
 296                         return help();
 297                 case '?':
 298                         return -EINVAL;
 299                 default:
 300                         assert_not_reached("Unknown option");
 301                 }
 302         }
 303
 304         if (!arg_dry_run || ping) {
 305                 r = must_be_root();
 306                 if (r < 0)
 307                         return r;
 308         }
 309
 310         if (ping) {
 311                 _cleanup_(udev_ctrl_unrefp) struct udev_ctrl *uctrl = NULL;
 312
 313                 r = udev_ctrl_new(&uctrl);
 314                 if (r < 0)
 315                         return log_error_errno(r, "Failed to initialize udev control: %m");
 316
 317                 r = udev_ctrl_send_ping(uctrl);
 318                 if (r < 0)
 319                         return log_error_errno(r, "Failed to connect to udev daemon: %m");
 320
 321                 r = udev_ctrl_wait(uctrl, ping_timeout_usec);
 322                 if (r < 0)
 323                         return log_error_errno(r, "Failed to wait for daemon to reply: %m");
 324         }
 325
 326         for (; optind < argc; optind++) {
 327                 _cleanup_(sd_device_unrefp) sd_device *dev = NULL;
 328
 329                 r = find_device(argv[optind], NULL, &dev);
 330                 if (r < 0)
 331                         return log_error_errno(r, "Failed to open the device '%s': %m", argv[optind]);
 332
 333                 r = device_enumerator_add_match_parent_incremental(e, dev);
 334                 if (r < 0)
 335                         return log_error_errno(r, "Failed to add parent match '%s': %m", argv[optind]);
 336         }
 337
 338         if (settle) {
 339                 settle_set = set_new(&string_hash_ops);
 340                 if (!settle_set)
 341                         return log_oom();
 342
 343                 r = sd_event_default(&event);
 344                 if (r < 0)
 345                         return log_error_errno(r, "Failed to get default event: %m");
 346
 347                 r = sd_device_monitor_new(&m);
 348                 if (r < 0)
 349                         return log_error_errno(r, "Failed to create device monitor object: %m");
 350
 351                 r = sd_device_monitor_attach_event(m, event);
 352                 if (r < 0)
 353                         return log_error_errno(r, "Failed to attach event to device monitor: %m");
 354
 355                 r = sd_device_monitor_start(m, device_monitor_handler, settle_set);
 356                 if (r < 0)
 357                         return log_error_errno(r, "Failed to start device monitor: %m");
 358         }
 359
 360         switch (device_type) {
 361         case TYPE_SUBSYSTEMS:
 362                 r = device_enumerator_scan_subsystems(e);
 363                 if (r < 0)
 364                         return log_error_errno(r, "Failed to scan subsystems: %m");
 365                 break;
 366         case TYPE_DEVICES:
 367                 r = device_enumerator_scan_devices(e);
 368                 if (r < 0)
 369                         return log_error_errno(r, "Failed to scan devices: %m");
 370                 break;
 371         default:
 372                 assert_not_reached("Unknown device type");
 373         }
 374         r = exec_list(e, action, settle_set);
 375         if (r < 0)
 376                 return r;
 377
 378         if (event && !set_isempty(settle_set)) {
 379                 r = sd_event_loop(event);
 380                 if (r < 0)
 381                         return log_error_errno(r, "Event loop failed: %m");
 382         }
 383
 384         return 0;
 385 }