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