src/udev/udevadm-settle.c

   1 /*
   2  * Copyright (C) 2006-2009 Kay Sievers <kay@vrfy.org>
   3  * Copyright (C) 2009 Canonical Ltd.
   4  * Copyright (C) 2009 Scott James Remnant <scott@netsplit.com>
   5  *
   6  * This program is free software: you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation, either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <stdlib.h>
  21 #include <stddef.h>
  22 #include <string.h>
  23 #include <stdio.h>
  24 #include <unistd.h>
  25 #include <errno.h>
  26 #include <dirent.h>
  27 #include <fcntl.h>
  28 #include <syslog.h>
  29 #include <getopt.h>
  30 #include <signal.h>
  31 #include <time.h>
  32 #include <sys/inotify.h>
  33 #include <sys/poll.h>
  34 #include <sys/stat.h>
  35 #include <sys/types.h>
  36
  37 #include "udev.h"
  38 #include "util.h"
  39
  40 static void help(void) {
  41         printf("Usage: udevadm settle OPTIONS\n"
  42                "  -t,--timeout=<seconds>     maximum time to wait for events\n"
  43                "  -s,--seq-start=<seqnum>    first seqnum to wait for\n"
  44                "  -e,--seq-end=<seqnum>      last seqnum to wait for\n"
  45                "  -E,--exit-if-exists=<file> stop waiting if file exists\n"
  46                "  -q,--quiet                 do not print list after timeout\n"
  47                "  -h,--help\n\n");
  48 }
  49
  50 static int adm_settle(struct udev *udev, int argc, char *argv[])
  51 {
  52         static const struct option options[] = {
  53                 { "seq-start",      required_argument, NULL, 's' },
  54                 { "seq-end",        required_argument, NULL, 'e' },
  55                 { "timeout",        required_argument, NULL, 't' },
  56                 { "exit-if-exists", required_argument, NULL, 'E' },
  57                 { "quiet",          no_argument,       NULL, 'q' },
  58                 { "help",           no_argument,       NULL, 'h' },
  59                 {}
  60         };
  61         usec_t start_usec = now(CLOCK_MONOTONIC);
  62         usec_t start = 0;
  63         usec_t end = 0;
  64         int quiet = 0;
  65         const char *exists = NULL;
  66         unsigned int timeout = 120;
  67         struct pollfd pfd[1] = { {.fd = -1}, };
  68         struct udev_queue *udev_queue = NULL;
  69         int rc = EXIT_FAILURE, c;
  70
  71         while ((c = getopt_long(argc, argv, "s:e:t:E:qh", options, NULL)) >= 0)
  72                 switch (c) {
  73                 case 's':
  74                         start = strtoull(optarg, NULL, 0);
  75                         break;
  76                 case 'e':
  77                         end = strtoull(optarg, NULL, 0);
  78                         break;
  79                 case 't': {
  80                         int r;
  81
  82                         r = safe_atou(optarg, &timeout);
  83                         if (r < 0) {
  84                                 fprintf(stderr, "Invalid timeout value '%s': %s\n",
  85                                         optarg, strerror(-r));
  86                                 exit(EXIT_FAILURE);
  87                         };
  88                         break;
  89                 }
  90                 case 'E':
  91                         exists = optarg;
  92                         break;
  93                 case 'q':
  94                         quiet = 1;
  95                         break;
  96                 case 'h':
  97                         help();
  98                         exit(EXIT_SUCCESS);
  99                 case '?':
 100                         exit(EXIT_FAILURE);
 101                 default:
 102                         assert_not_reached("Unkown argument");
 103                 }
 104
 105         if (optind < argc) {
 106                 fprintf(stderr, "Extraneous argument: '%s'\n", argv[optind]);
 107                 exit(EXIT_FAILURE);
 108         }
 109
 110         udev_queue = udev_queue_new(udev);
 111         if (udev_queue == NULL)
 112                 exit(2);
 113
 114         if (start > 0) {
 115                 unsigned long long kernel_seq;
 116
 117                 kernel_seq = udev_queue_get_kernel_seqnum(udev_queue);
 118
 119                 /* unless specified, the last event is the current kernel seqnum */
 120                 if (end == 0)
 121                         end = udev_queue_get_kernel_seqnum(udev_queue);
 122
 123                 if (start > end) {
 124                         log_error("seq-start larger than seq-end, ignoring\n");
 125                         start = 0;
 126                         end = 0;
 127                 }
 128
 129                 if (start > kernel_seq || end > kernel_seq) {
 130                         log_error("seq-start or seq-end larger than current kernel value, ignoring\n");
 131                         start = 0;
 132                         end = 0;
 133                 }
 134                 log_debug("start=%llu end=%llu current=%llu\n", (unsigned long long)start, (unsigned long long)end, kernel_seq);
 135         } else {
 136                 if (end > 0) {
 137                         log_error("seq-end needs seq-start parameter, ignoring\n");
 138                         end = 0;
 139                 }
 140         }
 141
 142         /* guarantee that the udev daemon isn't pre-processing */
 143         if (getuid() == 0) {
 144                 struct udev_ctrl *uctrl;
 145
 146                 uctrl = udev_ctrl_new(udev);
 147                 if (uctrl != NULL) {
 148                         if (udev_ctrl_send_ping(uctrl, timeout) < 0) {
 149                                 log_debug("no connection to daemon\n");
 150                                 udev_ctrl_unref(uctrl);
 151                                 rc = EXIT_SUCCESS;
 152                                 goto out;
 153                         }
 154                         udev_ctrl_unref(uctrl);
 155                 }
 156         }
 157
 158         pfd[0].events = POLLIN;
 159         pfd[0].fd = inotify_init1(IN_CLOEXEC);
 160         if (pfd[0].fd < 0) {
 161                 log_error("inotify_init failed: %m\n");
 162         } else {
 163                 if (inotify_add_watch(pfd[0].fd, "/run/udev" , IN_MOVED_TO) < 0) {
 164                         log_error("watching /run/udev failed\n");
 165                         close(pfd[0].fd);
 166                         pfd[0].fd = -1;
 167                 }
 168         }
 169
 170         for (;;) {
 171                 struct stat statbuf;
 172
 173                 if (exists != NULL && stat(exists, &statbuf) == 0) {
 174                         rc = EXIT_SUCCESS;
 175                         break;
 176                 }
 177
 178                 if (start > 0) {
 179                         /* if asked for, wait for a specific sequence of events */
 180                         if (udev_queue_get_seqnum_sequence_is_finished(udev_queue, start, end) == 1) {
 181                                 rc = EXIT_SUCCESS;
 182                                 break;
 183                         }
 184                 } else {
 185                         /* exit if queue is empty */
 186                         if (udev_queue_get_queue_is_empty(udev_queue)) {
 187                                 rc = EXIT_SUCCESS;
 188                                 break;
 189                         }
 190                 }
 191
 192                 if (pfd[0].fd >= 0) {
 193                         int delay;
 194
 195                         if (exists != NULL || start > 0)
 196                                 delay = 100;
 197                         else
 198                                 delay = 1000;
 199                         /* wake up after delay, or immediately after the queue is rebuilt */
 200                         if (poll(pfd, 1, delay) > 0 && pfd[0].revents & POLLIN) {
 201                                 char buf[sizeof(struct inotify_event) + PATH_MAX];
 202
 203                                 read(pfd[0].fd, buf, sizeof(buf));
 204                         }
 205                 } else {
 206                         sleep(1);
 207                 }
 208
 209                 if (timeout > 0) {
 210                         usec_t age_usec;
 211
 212                         age_usec = now(CLOCK_MONOTONIC) - start_usec;
 213                         if (age_usec / (1000 * 1000) >= timeout) {
 214                                 struct udev_list_entry *list_entry;
 215
 216                                 if (!quiet && udev_queue_get_queued_list_entry(udev_queue) != NULL) {
 217                                         log_debug("timeout waiting for udev queue\n");
 218                                         printf("\nudevadm settle - timeout of %i seconds reached, the event queue contains:\n", timeout);
 219                                         udev_list_entry_foreach(list_entry, udev_queue_get_queued_list_entry(udev_queue))
 220                                                 printf("  %s (%s)\n",
 221                                                 udev_list_entry_get_name(list_entry),
 222                                                 udev_list_entry_get_value(list_entry));
 223                                 }
 224
 225                                 break;
 226                         }
 227                 }
 228         }
 229 out:
 230         if (pfd[0].fd >= 0)
 231                 close(pfd[0].fd);
 232         udev_queue_unref(udev_queue);
 233         return rc;
 234 }
 235
 236 const struct udevadm_cmd udevadm_settle = {
 237         .name = "settle",
 238         .cmd = adm_settle,
 239         .help = "wait for the event queue to finish",
 240 };