udev/udevadm-settle.c

   1 /*
   2  * Copyright (C) 2006-2008 Kay Sievers <kay@vrfy.org>
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include <stdlib.h>
  19 #include <stddef.h>
  20 #include <string.h>
  21 #include <stdio.h>
  22 #include <unistd.h>
  23 #include <errno.h>
  24 #include <dirent.h>
  25 #include <fcntl.h>
  26 #include <syslog.h>
  27 #include <getopt.h>
  28 #include <signal.h>
  29 #include <sys/stat.h>
  30 #include <sys/types.h>
  31
  32 #include "udev.h"
  33
  34 #define DEFAULT_TIMEOUT                 180
  35 #define LOOP_PER_SECOND                 20
  36
  37 static int volatile is_timeout;
  38
  39 static void asmlinkage sig_handler(int signum)
  40 {
  41         switch (signum) {
  42                 case SIGALRM:
  43                         is_timeout = 1;
  44         }
  45 }
  46
  47 int udevadm_settle(struct udev *udev, int argc, char *argv[])
  48 {
  49         static const struct option options[] = {
  50                 { "seq-start", required_argument, NULL, 's' },
  51                 { "seq-end", required_argument, NULL, 'e' },
  52                 { "timeout", required_argument, NULL, 't' },
  53                 { "quiet", no_argument, NULL, 'q' },
  54                 { "help", no_argument, NULL, 'h' },
  55                 {}
  56         };
  57         unsigned long long start = 0;
  58         unsigned long long end = 0;
  59         int quiet = 0;
  60         int timeout = 0;
  61         struct sigaction act;
  62         struct udev_queue *udev_queue = NULL;
  63         int rc = 0;
  64
  65         dbg(udev, "version %s\n", VERSION);
  66
  67         /* set signal handlers */
  68         memset(&act, 0x00, sizeof(act));
  69         act.sa_handler = (void (*)(int)) sig_handler;
  70         sigemptyset (&act.sa_mask);
  71         act.sa_flags = 0;
  72         sigaction(SIGALRM, &act, NULL);
  73
  74         while (1) {
  75                 int option;
  76                 int seconds;
  77
  78                 option = getopt_long(argc, argv, "s:e:t:qh", options, NULL);
  79                 if (option == -1)
  80                         break;
  81
  82                 switch (option) {
  83                 case 's':
  84                         start = strtoull(optarg, NULL, 0);
  85                         break;
  86                 case 'e':
  87                         end = strtoull(optarg, NULL, 0);
  88                         break;
  89                 case 't':
  90                         seconds = atoi(optarg);
  91                         if (seconds >= 0)
  92                                 timeout = seconds;
  93                         else
  94                                 fprintf(stderr, "invalid timeout value\n");
  95                         dbg(udev, "timeout=%i\n", timeout);
  96                         break;
  97                 case 'q':
  98                         quiet = 1;
  99                         break;
 100                 case 'h':
 101                         printf("Usage: udevadm settle OPTIONS\n"
 102                                "  --timeout=<seconds>   maximum time to wait for events\n"
 103                                "  --seq-start=<seqnum>  first seqnum to wait for\n"
 104                                "  --seq-end=<seqnum>    last seqnum to wait for\n"
 105                                "  --quiet               do not print list after timeout\n"
 106                                "  --help\n\n");
 107                         goto exit;
 108                 }
 109         }
 110
 111         if (timeout > 0)
 112                 alarm(timeout);
 113         else
 114                 alarm(DEFAULT_TIMEOUT);
 115
 116         udev_queue = udev_queue_new(udev);
 117         if (udev_queue == NULL)
 118                 goto exit;
 119
 120         if (start > 0) {
 121                 unsigned long long kernel_seq;
 122
 123                 kernel_seq = udev_queue_get_kernel_seqnum(udev_queue);
 124
 125                 /* unless specified, the last event is the current kernel seqnum */
 126                 if (end == 0)
 127                         end = udev_queue_get_kernel_seqnum(udev_queue);
 128
 129                 if (start > end) {
 130                         err(udev, "seq-start larger than seq-end, ignoring\n");
 131                         fprintf(stderr, "seq-start larger than seq-end, ignoring\n");
 132                         start = 0;
 133                         end = 0;
 134                 }
 135
 136                 if (start > kernel_seq || end > kernel_seq) {
 137                         err(udev, "seq-start or seq-end larger than current kernel value, ignoring\n");
 138                         fprintf(stderr, "seq-start or seq-end larger than current kernel value, ignoring\n");
 139                         start = 0;
 140                         end = 0;
 141                 }
 142                 info(udev, "start=%llu end=%llu current=%llu\n", start, end, kernel_seq);
 143         } else {
 144                 if (end > 0) {
 145                         err(udev, "seq-end needs seq-start parameter, ignoring\n");
 146                         fprintf(stderr, "seq-end needs seq-start parameter, ignoring\n");
 147                         end = 0;
 148                 }
 149         }
 150
 151         while (!is_timeout) {
 152                 /* exit if queue is empty */
 153                 if (udev_queue_get_queue_is_empty(udev_queue))
 154                         break;
 155
 156                 /* if asked for, wait for a specific sequence of events */
 157                 if (start > 0) {
 158                         unsigned long long seq;
 159                         int finished;
 160
 161                         finished = 0;
 162                         for (seq = start; seq <= end; seq++) {
 163                                 finished  = udev_queue_get_seqnum_is_finished(udev_queue, seq);
 164                                 if (!finished)
 165                                         break;
 166                         }
 167                         if (finished)
 168                                 break;
 169                 }
 170                 usleep(1000 * 1000 / LOOP_PER_SECOND);
 171         }
 172
 173         /* if we reached the timeout, print the list of remaining events */
 174         if (is_timeout) {
 175                 struct udev_list_entry *list_entry;
 176
 177                 if (!quiet) {
 178                         info(udev, "timeout waiting for udev queue\n");
 179                         printf("\nudevadm settle - timeout of %i seconds reached, the event queue contains:\n", timeout);
 180                         udev_list_entry_foreach(list_entry, udev_queue_get_queued_list_entry(udev_queue))
 181                                 printf("  %s (%s)\n",
 182                                        udev_list_entry_get_name(list_entry),
 183                                        udev_list_entry_get_value(list_entry));
 184                 }
 185                 rc = 1;
 186         }
 187 exit:
 188         udev_queue_unref(udev_queue);
 189         return rc;
 190 }