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
  39 static int adm_settle(struct udev *udev, int argc, char *argv[])
  40 {
  41         static const struct option options[] = {
  42                 { "seq-start", required_argument, NULL, 's' },
  43                 { "seq-end", required_argument, NULL, 'e' },
  44                 { "timeout", required_argument, NULL, 't' },
  45                 { "exit-if-exists", required_argument, NULL, 'E' },
  46                 { "quiet", no_argument, NULL, 'q' },
  47                 { "help", no_argument, NULL, 'h' },
  48                 {}
  49         };
  50         unsigned long long start_usec = now_usec();
  51         unsigned long long start = 0;
  52         unsigned long long end = 0;
  53         int quiet = 0;
  54         const char *exists = NULL;
  55         unsigned int timeout = 120;
  56         struct pollfd pfd[1];
  57         struct udev_queue *udev_queue = NULL;
  58         int rc = EXIT_FAILURE;
  59
  60         dbg(udev, "version %s\n", VERSION);
  61
  62         for (;;) {
  63                 int option;
  64                 int seconds;
  65
  66                 option = getopt_long(argc, argv, "s:e:t:E:qh", options, NULL);
  67                 if (option == -1)
  68                         break;
  69
  70                 switch (option) {
  71                 case 's':
  72                         start = strtoull(optarg, NULL, 0);
  73                         break;
  74                 case 'e':
  75                         end = strtoull(optarg, NULL, 0);
  76                         break;
  77                 case 't':
  78                         seconds = atoi(optarg);
  79                         if (seconds >= 0)
  80                                 timeout = seconds;
  81                         else
  82                                 fprintf(stderr, "invalid timeout value\n");
  83                         dbg(udev, "timeout=%i\n", timeout);
  84                         break;
  85                 case 'q':
  86                         quiet = 1;
  87                         break;
  88                 case 'E':
  89                         exists = optarg;
  90                         break;
  91                 case 'h':
  92                         printf("Usage: udevadm settle OPTIONS\n"
  93                                "  --timeout=<seconds>     maximum time to wait for events\n"
  94                                "  --seq-start=<seqnum>    first seqnum to wait for\n"
  95                                "  --seq-end=<seqnum>      last seqnum to wait for\n"
  96                                "  --exit-if-exists=<file> stop waiting if file exists\n"
  97                                "  --quiet                 do not print list after timeout\n"
  98                                "  --help\n\n");
  99                         exit(EXIT_SUCCESS);
 100                 default:
 101                         exit(EXIT_FAILURE);
 102                 }
 103         }
 104
 105         udev_queue = udev_queue_new(udev);
 106         if (udev_queue == NULL)
 107                 exit(2);
 108
 109         if (start > 0) {
 110                 unsigned long long kernel_seq;
 111
 112                 kernel_seq = udev_queue_get_kernel_seqnum(udev_queue);
 113
 114                 /* unless specified, the last event is the current kernel seqnum */
 115                 if (end == 0)
 116                         end = udev_queue_get_kernel_seqnum(udev_queue);
 117
 118                 if (start > end) {
 119                         err(udev, "seq-start larger than seq-end, ignoring\n");
 120                         start = 0;
 121                         end = 0;
 122                 }
 123
 124                 if (start > kernel_seq || end > kernel_seq) {
 125                         err(udev, "seq-start or seq-end larger than current kernel value, ignoring\n");
 126                         start = 0;
 127                         end = 0;
 128                 }
 129                 info(udev, "start=%llu end=%llu current=%llu\n", start, end, kernel_seq);
 130         } else {
 131                 if (end > 0) {
 132                         err(udev, "seq-end needs seq-start parameter, ignoring\n");
 133                         end = 0;
 134                 }
 135         }
 136
 137         /* guarantee that the udev daemon isn't pre-processing */
 138         if (getuid() == 0) {
 139                 struct udev_ctrl *uctrl;
 140
 141                 uctrl = udev_ctrl_new(udev);
 142                 if (uctrl != NULL) {
 143                         if (udev_ctrl_send_ping(uctrl, timeout) < 0) {
 144                                 info(udev, "no connection to daemon\n");
 145                                 udev_ctrl_unref(uctrl);
 146                                 rc = EXIT_SUCCESS;
 147                                 goto out;
 148                         }
 149                         udev_ctrl_unref(uctrl);
 150                 }
 151         }
 152
 153         pfd[0].events = POLLIN;
 154         pfd[0].fd = inotify_init1(IN_CLOEXEC);
 155         if (pfd[0].fd < 0) {
 156                 err(udev, "inotify_init failed: %m\n");
 157         } else {
 158                 if (inotify_add_watch(pfd[0].fd, udev_get_run_path(udev), IN_MOVED_TO) < 0) {
 159                         err(udev, "watching '%s' failed\n", udev_get_run_path(udev));
 160                         close(pfd[0].fd);
 161                         pfd[0].fd = -1;
 162                 }
 163         }
 164
 165         for (;;) {
 166                 struct stat statbuf;
 167
 168                 if (exists != NULL && stat(exists, &statbuf) == 0) {
 169                         rc = EXIT_SUCCESS;
 170                         break;
 171                 }
 172
 173                 if (start > 0) {
 174                         /* if asked for, wait for a specific sequence of events */
 175                         if (udev_queue_get_seqnum_sequence_is_finished(udev_queue, start, end) == 1) {
 176                                 rc = EXIT_SUCCESS;
 177                                 break;
 178                         }
 179                 } else {
 180                         /* exit if queue is empty */
 181                         if (udev_queue_get_queue_is_empty(udev_queue)) {
 182                                 rc = EXIT_SUCCESS;
 183                                 break;
 184                         }
 185                 }
 186
 187                 if (pfd[0].fd >= 0) {
 188                         int delay;
 189
 190                         if (exists != NULL || start > 0)
 191                                 delay = 100;
 192                         else
 193                                 delay = 1000;
 194                         /* wake up after delay, or immediately after the queue is rebuilt */
 195                         if (poll(pfd, 1, delay) > 0 && pfd[0].revents & POLLIN) {
 196                                 char buf[sizeof(struct inotify_event) + PATH_MAX];
 197
 198                                 read(pfd[0].fd, buf, sizeof(buf));
 199                         }
 200                 } else {
 201                         sleep(1);
 202                 }
 203
 204                 if (timeout > 0) {
 205                         unsigned long long age_usec;
 206
 207                         age_usec = now_usec() - start_usec;
 208                         if (age_usec / (1000 * 1000) >= timeout) {
 209                                 struct udev_list_entry *list_entry;
 210
 211                                 if (!quiet && udev_queue_get_queued_list_entry(udev_queue) != NULL) {
 212                                         info(udev, "timeout waiting for udev queue\n");
 213                                         printf("\nudevadm settle - timeout of %i seconds reached, the event queue contains:\n", timeout);
 214                                         udev_list_entry_foreach(list_entry, udev_queue_get_queued_list_entry(udev_queue))
 215                                                 printf("  %s (%s)\n",
 216                                                 udev_list_entry_get_name(list_entry),
 217                                                 udev_list_entry_get_value(list_entry));
 218                                 }
 219
 220                                 break;
 221                         }
 222                 }
 223         }
 224 out:
 225         if (pfd[0].fd >= 0)
 226                 close(pfd[0].fd);
 227         udev_queue_unref(udev_queue);
 228         return rc;
 229 }
 230
 231 const struct udevadm_cmd udevadm_settle = {
 232         .name = "settle",
 233         .cmd = adm_settle,
 234         .help = "wait for the event queue to finish",
 235 };