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 int udevadm_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(0);
 100                 }
 101         }
 102
 103         udev_queue = udev_queue_new(udev);
 104         if (udev_queue == NULL)
 105                 exit(2);
 106
 107         if (start > 0) {
 108                 unsigned long long kernel_seq;
 109
 110                 kernel_seq = udev_queue_get_kernel_seqnum(udev_queue);
 111
 112                 /* unless specified, the last event is the current kernel seqnum */
 113                 if (end == 0)
 114                         end = udev_queue_get_kernel_seqnum(udev_queue);
 115
 116                 if (start > end) {
 117                         err(udev, "seq-start larger than seq-end, ignoring\n");
 118                         start = 0;
 119                         end = 0;
 120                 }
 121
 122                 if (start > kernel_seq || end > kernel_seq) {
 123                         err(udev, "seq-start or seq-end larger than current kernel value, ignoring\n");
 124                         start = 0;
 125                         end = 0;
 126                 }
 127                 info(udev, "start=%llu end=%llu current=%llu\n", start, end, kernel_seq);
 128         } else {
 129                 if (end > 0) {
 130                         err(udev, "seq-end needs seq-start parameter, ignoring\n");
 131                         end = 0;
 132                 }
 133         }
 134
 135         /* guarantee that the udev daemon isn't pre-processing */
 136         if (getuid() == 0) {
 137                 struct udev_ctrl *uctrl;
 138
 139                 uctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
 140                 if (uctrl != NULL) {
 141                         if (udev_ctrl_send_ping(uctrl, timeout) < 0) {
 142                                 info(udev, "no connection to daemon\n");
 143                                 udev_ctrl_unref(uctrl);
 144                                 rc = EXIT_SUCCESS;
 145                                 goto out;
 146                         }
 147                         udev_ctrl_unref(uctrl);
 148                 }
 149         }
 150
 151         pfd[0].events = POLLIN;
 152         pfd[0].fd = inotify_init1(IN_CLOEXEC);
 153         if (pfd[0].fd < 0) {
 154                 err(udev, "inotify_init failed: %m\n");
 155         } else {
 156                 if (inotify_add_watch(pfd[0].fd, udev_get_run_path(udev), IN_CLOSE_WRITE) < 0) {
 157                         err(udev, "watching '%s' failed\n", udev_get_run_path(udev));
 158                         close(pfd[0].fd);
 159                         pfd[0].fd = -1;
 160                 }
 161         }
 162
 163         for (;;) {
 164                 struct stat statbuf;
 165
 166                 if (exists != NULL && stat(exists, &statbuf) == 0) {
 167                         rc = EXIT_SUCCESS;
 168                         break;
 169                 }
 170
 171                 if (start > 0) {
 172                         /* if asked for, wait for a specific sequence of events */
 173                         if (udev_queue_get_seqnum_sequence_is_finished(udev_queue, start, end) == 1) {
 174                                 rc = EXIT_SUCCESS;
 175                                 break;
 176                         }
 177                 } else {
 178                         /* exit if queue is empty */
 179                         if (udev_queue_get_queue_is_empty(udev_queue)) {
 180                                 rc = EXIT_SUCCESS;
 181                                 break;
 182                         }
 183                 }
 184
 185                 if (pfd[0].fd >= 0) {
 186                         /* wake up once every second, or whenever the queue file gets gets closed */
 187                         if (poll(pfd, 1, 1000) > 0 && pfd[0].revents & POLLIN) {
 188                                 char buf[sizeof(struct inotify_event) + PATH_MAX];
 189
 190                                 read(pfd[0].fd, buf, sizeof(buf));
 191                         }
 192                 } else {
 193                         sleep(1);
 194                 }
 195
 196                 if (timeout > 0) {
 197                         unsigned long long age_usec;
 198
 199                         age_usec = now_usec() - start_usec;
 200                         if (age_usec / (1000 * 1000) >= timeout) {
 201                                 struct udev_list_entry *list_entry;
 202
 203                                 if (!quiet && udev_queue_get_queued_list_entry(udev_queue) != NULL) {
 204                                         info(udev, "timeout waiting for udev queue\n");
 205                                         printf("\nudevadm settle - timeout of %i seconds reached, the event queue contains:\n", timeout);
 206                                         udev_list_entry_foreach(list_entry, udev_queue_get_queued_list_entry(udev_queue))
 207                                                 printf("  %s (%s)\n",
 208                                                 udev_list_entry_get_name(list_entry),
 209                                                 udev_list_entry_get_value(list_entry));
 210                                 }
 211
 212                                 break;
 213                         }
 214                 }
 215         }
 216 out:
 217         if (pfd[0].fd >= 0)
 218                 close(pfd[0].fd);
 219         udev_queue_unref(udev_queue);
 220         return rc;
 221 }