udevadm-settle.c revision 3e2147858f21943d5f4a781c60f33ac22c6096ed
/*
* Copyright (C) 2006-2009 Kay Sievers <kay@vrfy.org>
* Copyright (C) 2009 Canonical Ltd.
* Copyright (C) 2009 Scott James Remnant <scott@netsplit.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <dirent.h>
#include <fcntl.h>
#include <syslog.h>
#include <getopt.h>
#include <signal.h>
#include <time.h>
#include <sys/inotify.h>
#include <sys/poll.h>
#include <sys/stat.h>
#include <sys/types.h>
#include "udev.h"
static int adm_settle(struct udev *udev, int argc, char *argv[])
{
static const struct option options[] = {
{ "seq-start", required_argument, NULL, 's' },
{ "seq-end", required_argument, NULL, 'e' },
{ "timeout", required_argument, NULL, 't' },
{ "exit-if-exists", required_argument, NULL, 'E' },
{ "quiet", no_argument, NULL, 'q' },
{ "help", no_argument, NULL, 'h' },
{}
};
unsigned long long start_usec = now_usec();
unsigned long long start = 0;
unsigned long long end = 0;
int quiet = 0;
const char *exists = NULL;
unsigned int timeout = 120;
struct pollfd pfd[1];
struct udev_queue *udev_queue = NULL;
int rc = EXIT_FAILURE;
dbg(udev, "version %s\n", VERSION);
for (;;) {
int option;
int seconds;
option = getopt_long(argc, argv, "s:e:t:E:qh", options, NULL);
if (option == -1)
break;
switch (option) {
case 's':
start = strtoull(optarg, NULL, 0);
break;
case 'e':
end = strtoull(optarg, NULL, 0);
break;
case 't':
seconds = atoi(optarg);
if (seconds >= 0)
timeout = seconds;
else
fprintf(stderr, "invalid timeout value\n");
dbg(udev, "timeout=%i\n", timeout);
break;
case 'q':
quiet = 1;
break;
case 'E':
exists = optarg;
break;
case 'h':
printf("Usage: udevadm settle OPTIONS\n"
" --timeout=<seconds> maximum time to wait for events\n"
" --seq-start=<seqnum> first seqnum to wait for\n"
" --seq-end=<seqnum> last seqnum to wait for\n"
" --exit-if-exists=<file> stop waiting if file exists\n"
" --quiet do not print list after timeout\n"
" --help\n\n");
exit(EXIT_SUCCESS);
default:
exit(EXIT_FAILURE);
}
}
udev_queue = udev_queue_new(udev);
if (udev_queue == NULL)
exit(2);
if (start > 0) {
unsigned long long kernel_seq;
kernel_seq = udev_queue_get_kernel_seqnum(udev_queue);
/* unless specified, the last event is the current kernel seqnum */
if (end == 0)
end = udev_queue_get_kernel_seqnum(udev_queue);
if (start > end) {
err(udev, "seq-start larger than seq-end, ignoring\n");
start = 0;
end = 0;
}
if (start > kernel_seq || end > kernel_seq) {
err(udev, "seq-start or seq-end larger than current kernel value, ignoring\n");
start = 0;
end = 0;
}
info(udev, "start=%llu end=%llu current=%llu\n", start, end, kernel_seq);
} else {
if (end > 0) {
err(udev, "seq-end needs seq-start parameter, ignoring\n");
end = 0;
}
}
/* guarantee that the udev daemon isn't pre-processing */
if (getuid() == 0) {
struct udev_ctrl *uctrl;
uctrl = udev_ctrl_new(udev);
if (uctrl != NULL) {
if (udev_ctrl_send_ping(uctrl, timeout) < 0) {
info(udev, "no connection to daemon\n");
udev_ctrl_unref(uctrl);
rc = EXIT_SUCCESS;
goto out;
}
udev_ctrl_unref(uctrl);
}
}
pfd[0].events = POLLIN;
pfd[0].fd = inotify_init1(IN_CLOEXEC);
if (pfd[0].fd < 0) {
err(udev, "inotify_init failed: %m\n");
} else {
if (inotify_add_watch(pfd[0].fd, udev_get_run_path(udev), IN_MOVED_TO) < 0) {
err(udev, "watching '%s' failed\n", udev_get_run_path(udev));
close(pfd[0].fd);
pfd[0].fd = -1;
}
}
for (;;) {
struct stat statbuf;
if (exists != NULL && stat(exists, &statbuf) == 0) {
rc = EXIT_SUCCESS;
break;
}
if (start > 0) {
/* if asked for, wait for a specific sequence of events */
if (udev_queue_get_seqnum_sequence_is_finished(udev_queue, start, end) == 1) {
rc = EXIT_SUCCESS;
break;
}
} else {
/* exit if queue is empty */
if (udev_queue_get_queue_is_empty(udev_queue)) {
rc = EXIT_SUCCESS;
break;
}
}
if (pfd[0].fd >= 0) {
int delay;
if (exists != NULL || start > 0)
delay = 100;
else
delay = 1000;
/* wake up after delay, or immediately after the queue is rebuilt */
if (poll(pfd, 1, delay) > 0 && pfd[0].revents & POLLIN) {
char buf[sizeof(struct inotify_event) + PATH_MAX];
read(pfd[0].fd, buf, sizeof(buf));
}
} else {
sleep(1);
}
if (timeout > 0) {
unsigned long long age_usec;
age_usec = now_usec() - start_usec;
if (age_usec / (1000 * 1000) >= timeout) {
struct udev_list_entry *list_entry;
if (!quiet && udev_queue_get_queued_list_entry(udev_queue) != NULL) {
info(udev, "timeout waiting for udev queue\n");
printf("\nudevadm settle - timeout of %i seconds reached, the event queue contains:\n", timeout);
udev_list_entry_foreach(list_entry, udev_queue_get_queued_list_entry(udev_queue))
printf(" %s (%s)\n",
udev_list_entry_get_name(list_entry),
udev_list_entry_get_value(list_entry));
}
break;
}
}
}
out:
if (pfd[0].fd >= 0)
close(pfd[0].fd);
udev_queue_unref(udev_queue);
return rc;
}
const struct udevadm_cmd udevadm_settle = {
.name = "settle",
.cmd = adm_settle,
.help = "wait for the event queue to finish",
};