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 "udev-util.h"
  39 #include "util.h"
  40
  41 static void help(void) {
  42         printf("Usage: udevadm settle OPTIONS\n"
  43                "  -t,--timeout=<seconds>     maximum time to wait for events\n"
  44                "  -s,--seq-start=<seqnum>    first seqnum to wait for\n"
  45                "  -e,--seq-end=<seqnum>      last seqnum to wait for\n"
  46                "  -E,--exit-if-exists=<file> stop waiting if file exists\n"
  47                "  -q,--quiet                 do not print list after timeout\n"
  48                "  -h,--help\n\n");
  49 }
  50
  51 static int adm_settle(struct udev *udev, int argc, char *argv[])
  52 {
  53         static const struct option options[] = {
  54                 { "seq-start",      required_argument, NULL, 's' },
  55                 { "seq-end",        required_argument, NULL, 'e' },
  56                 { "timeout",        required_argument, NULL, 't' },
  57                 { "exit-if-exists", required_argument, NULL, 'E' },
  58                 { "quiet",          no_argument,       NULL, 'q' },
  59                 { "help",           no_argument,       NULL, 'h' },
  60                 {}
  61         };
  62         usec_t start_usec = now(CLOCK_MONOTONIC);
  63         usec_t start = 0;
  64         usec_t end = 0;
  65         int quiet = 0;
  66         const char *exists = NULL;
  67         unsigned int timeout = 120;
  68         struct pollfd pfd[1] = { {.fd = -1}, };
  69         _cleanup_udev_queue_unref_ struct udev_queue *udev_queue = NULL;
  70         int rc = EXIT_FAILURE, c;
  71
  72         while ((c = getopt_long(argc, argv, "s:e:t:E:qh", options, NULL)) >= 0)
  73                 switch (c) {
  74                 case 's':
  75                         start = strtoull(optarg, NULL, 0);
  76                         break;
  77                 case 'e':
  78                         end = strtoull(optarg, NULL, 0);
  79                         break;
  80                 case 't': {
  81                         int r;
  82
  83                         r = safe_atou(optarg, &timeout);
  84                         if (r < 0) {
  85                                 fprintf(stderr, "Invalid timeout value '%s': %s\n",
  86                                         optarg, strerror(-r));
  87                                 exit(EXIT_FAILURE);
  88                         };
  89                         break;
  90                 }
  91                 case 'E':
  92                         exists = optarg;
  93                         break;
  94                 case 'q':
  95                         quiet = 1;
  96                         break;
  97                 case 'h':
  98                         help();
  99                         exit(EXIT_SUCCESS);
 100                 case '?':
 101                         exit(EXIT_FAILURE);
 102                 default:
 103                         assert_not_reached("Unkown argument");
 104                 }
 105
 106         if (optind < argc) {
 107                 fprintf(stderr, "Extraneous argument: '%s'\n", argv[optind]);
 108                 exit(EXIT_FAILURE);
 109         }
 110
 111         udev_queue = udev_queue_new(udev);
 112         if (udev_queue == NULL)
 113                 exit(2);
 114
 115         if (start > 0) {
 116                 unsigned long long kernel_seq;
 117
 118                 kernel_seq = udev_queue_get_kernel_seqnum(udev_queue);
 119
 120                 /* unless specified, the last event is the current kernel seqnum */
 121                 if (end == 0)
 122                         end = udev_queue_get_kernel_seqnum(udev_queue);
 123
 124                 if (start > end) {
 125                         log_error("seq-start larger than seq-end, ignoring");
 126                         start = 0;
 127                         end = 0;
 128                 }
 129
 130                 if (start > kernel_seq || end > kernel_seq) {
 131                         log_error("seq-start or seq-end larger than current kernel value, ignoring");
 132                         start = 0;
 133                         end = 0;
 134                 }
 135                 log_debug("start=%llu end=%llu current=%llu", (unsigned long long)start, (unsigned long long)end, kernel_seq);
 136         } else {
 137                 if (end > 0) {
 138                         log_error("seq-end needs seq-start parameter, ignoring");
 139                         end = 0;
 140                 }
 141         }
 142
 143         /* guarantee that the udev daemon isn't pre-processing */
 144         if (getuid() == 0) {
 145                 struct udev_ctrl *uctrl;
 146
 147                 uctrl = udev_ctrl_new(udev);
 148                 if (uctrl != NULL) {
 149                         if (udev_ctrl_send_ping(uctrl, timeout) < 0) {
 150                                 log_debug("no connection to daemon");
 151                                 udev_ctrl_unref(uctrl);
 152                                 rc = EXIT_SUCCESS;
 153                                 goto out;
 154                         }
 155                         udev_ctrl_unref(uctrl);
 156                 }
 157         }
 158
 159         pfd[0].events = POLLIN;
 160         pfd[0].fd = inotify_init1(IN_CLOEXEC);
 161         if (pfd[0].fd < 0) {
 162                 log_error("inotify_init failed: %m");
 163         } else {
 164                 if (inotify_add_watch(pfd[0].fd, "/run/udev" , IN_MOVED_TO) < 0) {
 165                         log_error("watching /run/udev failed");
 166                         close(pfd[0].fd);
 167                         pfd[0].fd = -1;
 168                 }
 169         }
 170
 171         for (;;) {
 172                 struct stat statbuf;
 173
 174                 if (exists != NULL && stat(exists, &statbuf) == 0) {
 175                         rc = EXIT_SUCCESS;
 176                         break;
 177                 }
 178
 179                 if (start > 0) {
 180                         /* if asked for, wait for a specific sequence of events */
 181                         if (udev_queue_get_seqnum_sequence_is_finished(udev_queue, start, end) == 1) {
 182                                 rc = EXIT_SUCCESS;
 183                                 break;
 184                         }
 185                 } else {
 186                         /* exit if queue is empty */
 187                         if (udev_queue_get_queue_is_empty(udev_queue)) {
 188                                 rc = EXIT_SUCCESS;
 189                                 break;
 190                         }
 191                 }
 192
 193                 if (pfd[0].fd >= 0) {
 194                         int delay;
 195
 196                         if (exists != NULL || start > 0)
 197                                 delay = 100;
 198                         else
 199                                 delay = 1000;
 200                         /* wake up after delay, or immediately after the queue is rebuilt */
 201                         if (poll(pfd, 1, delay) > 0 && pfd[0].revents & POLLIN) {
 202                                 char buf[sizeof(struct inotify_event) + PATH_MAX];
 203
 204                                 read(pfd[0].fd, buf, sizeof(buf));
 205                         }
 206                 } else {
 207                         sleep(1);
 208                 }
 209
 210                 if (timeout > 0) {
 211                         usec_t age_usec;
 212
 213                         age_usec = now(CLOCK_MONOTONIC) - start_usec;
 214                         if (age_usec / (1000 * 1000) >= timeout) {
 215                                 struct udev_list_entry *list_entry;
 216
 217                                 if (!quiet && udev_queue_get_queued_list_entry(udev_queue) != NULL) {
 218                                         log_debug("timeout waiting for udev queue");
 219                                         printf("\nudevadm settle - timeout of %i seconds reached, the event queue contains:\n", timeout);
 220                                         udev_list_entry_foreach(list_entry, udev_queue_get_queued_list_entry(udev_queue))
 221                                                 printf("  %s (%s)\n",
 222                                                 udev_list_entry_get_name(list_entry),
 223                                                 udev_list_entry_get_value(list_entry));
 224                                 }
 225
 226                                 break;
 227                         }
 228                 }
 229         }
 230 out:
 231         if (pfd[0].fd >= 0)
 232                 close(pfd[0].fd);
 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 };