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Diffstat (limited to 'src/grp-udev/udevadm/udevadm-monitor.c')
-rw-r--r--src/grp-udev/udevadm/udevadm-monitor.c281
1 files changed, 281 insertions, 0 deletions
diff --git a/src/grp-udev/udevadm/udevadm-monitor.c b/src/grp-udev/udevadm/udevadm-monitor.c
new file mode 100644
index 0000000000..3503b19a21
--- /dev/null
+++ b/src/grp-udev/udevadm/udevadm-monitor.c
@@ -0,0 +1,281 @@
+/*
+ * Copyright (C) 2004-2010 Kay Sievers <kay@vrfy.org>
+ *
+ * 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 <errno.h>
+#include <getopt.h>
+#include <signal.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/epoll.h>
+#include <sys/time.h>
+#include <time.h>
+
+#include "systemd-basic/fd-util.h"
+#include "systemd-basic/formats-util.h"
+#include "systemd-shared/udev-util.h"
+#include "udev.h"
+
+static bool udev_exit;
+
+static void sig_handler(int signum) {
+ if (signum == SIGINT || signum == SIGTERM)
+ udev_exit = true;
+}
+
+static void print_device(struct udev_device *device, const char *source, int prop) {
+ struct timespec ts;
+
+ assert_se(clock_gettime(CLOCK_MONOTONIC, &ts) == 0);
+ printf("%-6s[%"PRI_TIME".%06ld] %-8s %s (%s)\n",
+ source,
+ ts.tv_sec, ts.tv_nsec/1000,
+ udev_device_get_action(device),
+ udev_device_get_devpath(device),
+ udev_device_get_subsystem(device));
+ if (prop) {
+ struct udev_list_entry *list_entry;
+
+ udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(device))
+ printf("%s=%s\n",
+ udev_list_entry_get_name(list_entry),
+ udev_list_entry_get_value(list_entry));
+ printf("\n");
+ }
+}
+
+static void help(void) {
+ printf("%s monitor [--property] [--kernel] [--udev] [--help]\n\n"
+ "Listen to kernel and udev events.\n\n"
+ " -h --help Show this help\n"
+ " --version Show package version\n"
+ " -p --property Print the event properties\n"
+ " -k --kernel Print kernel uevents\n"
+ " -u --udev Print udev events\n"
+ " -s --subsystem-match=SUBSYSTEM[/DEVTYPE] Filter events by subsystem\n"
+ " -t --tag-match=TAG Filter events by tag\n"
+ , program_invocation_short_name);
+}
+
+static int adm_monitor(struct udev *udev, int argc, char *argv[]) {
+ struct sigaction act = {};
+ sigset_t mask;
+ bool prop = false;
+ bool print_kernel = false;
+ bool print_udev = false;
+ _cleanup_udev_list_cleanup_ struct udev_list subsystem_match_list;
+ _cleanup_udev_list_cleanup_ struct udev_list tag_match_list;
+ _cleanup_udev_monitor_unref_ struct udev_monitor *udev_monitor = NULL;
+ _cleanup_udev_monitor_unref_ struct udev_monitor *kernel_monitor = NULL;
+ _cleanup_close_ int fd_ep = -1;
+ int fd_kernel = -1, fd_udev = -1;
+ struct epoll_event ep_kernel, ep_udev;
+ int c;
+
+ static const struct option options[] = {
+ { "property", no_argument, NULL, 'p' },
+ { "environment", no_argument, NULL, 'e' }, /* alias for -p */
+ { "kernel", no_argument, NULL, 'k' },
+ { "udev", no_argument, NULL, 'u' },
+ { "subsystem-match", required_argument, NULL, 's' },
+ { "tag-match", required_argument, NULL, 't' },
+ { "help", no_argument, NULL, 'h' },
+ {}
+ };
+
+ udev_list_init(udev, &subsystem_match_list, true);
+ udev_list_init(udev, &tag_match_list, true);
+
+ while ((c = getopt_long(argc, argv, "pekus:t:h", options, NULL)) >= 0)
+ switch (c) {
+ case 'p':
+ case 'e':
+ prop = true;
+ break;
+ case 'k':
+ print_kernel = true;
+ break;
+ case 'u':
+ print_udev = true;
+ break;
+ case 's':
+ {
+ char subsys[UTIL_NAME_SIZE];
+ char *devtype;
+
+ strscpy(subsys, sizeof(subsys), optarg);
+ devtype = strchr(subsys, '/');
+ if (devtype != NULL) {
+ devtype[0] = '\0';
+ devtype++;
+ }
+ udev_list_entry_add(&subsystem_match_list, subsys, devtype);
+ break;
+ }
+ case 't':
+ udev_list_entry_add(&tag_match_list, optarg, NULL);
+ break;
+ case 'h':
+ help();
+ return 0;
+ default:
+ return 1;
+ }
+
+ if (!print_kernel && !print_udev) {
+ print_kernel = true;
+ print_udev = true;
+ }
+
+ /* set signal handlers */
+ act.sa_handler = sig_handler;
+ act.sa_flags = SA_RESTART;
+ sigaction(SIGINT, &act, NULL);
+ sigaction(SIGTERM, &act, NULL);
+ sigemptyset(&mask);
+ sigaddset(&mask, SIGINT);
+ sigaddset(&mask, SIGTERM);
+ sigprocmask(SIG_UNBLOCK, &mask, NULL);
+
+ /* Callers are expecting to see events as they happen: Line buffering */
+ setlinebuf(stdout);
+
+ fd_ep = epoll_create1(EPOLL_CLOEXEC);
+ if (fd_ep < 0) {
+ log_error_errno(errno, "error creating epoll fd: %m");
+ return 1;
+ }
+
+ printf("monitor will print the received events for:\n");
+ if (print_udev) {
+ struct udev_list_entry *entry;
+
+ udev_monitor = udev_monitor_new_from_netlink(udev, "udev");
+ if (udev_monitor == NULL) {
+ fprintf(stderr, "error: unable to create netlink socket\n");
+ return 1;
+ }
+ udev_monitor_set_receive_buffer_size(udev_monitor, 128*1024*1024);
+ fd_udev = udev_monitor_get_fd(udev_monitor);
+
+ udev_list_entry_foreach(entry, udev_list_get_entry(&subsystem_match_list)) {
+ const char *subsys = udev_list_entry_get_name(entry);
+ const char *devtype = udev_list_entry_get_value(entry);
+
+ if (udev_monitor_filter_add_match_subsystem_devtype(udev_monitor, subsys, devtype) < 0)
+ fprintf(stderr, "error: unable to apply subsystem filter '%s'\n", subsys);
+ }
+
+ udev_list_entry_foreach(entry, udev_list_get_entry(&tag_match_list)) {
+ const char *tag = udev_list_entry_get_name(entry);
+
+ if (udev_monitor_filter_add_match_tag(udev_monitor, tag) < 0)
+ fprintf(stderr, "error: unable to apply tag filter '%s'\n", tag);
+ }
+
+ if (udev_monitor_enable_receiving(udev_monitor) < 0) {
+ fprintf(stderr, "error: unable to subscribe to udev events\n");
+ return 2;
+ }
+
+ memzero(&ep_udev, sizeof(struct epoll_event));
+ ep_udev.events = EPOLLIN;
+ ep_udev.data.fd = fd_udev;
+ if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_udev, &ep_udev) < 0) {
+ log_error_errno(errno, "fail to add fd to epoll: %m");
+ return 2;
+ }
+
+ printf("UDEV - the event which udev sends out after rule processing\n");
+ }
+
+ if (print_kernel) {
+ struct udev_list_entry *entry;
+
+ kernel_monitor = udev_monitor_new_from_netlink(udev, "kernel");
+ if (kernel_monitor == NULL) {
+ fprintf(stderr, "error: unable to create netlink socket\n");
+ return 3;
+ }
+ udev_monitor_set_receive_buffer_size(kernel_monitor, 128*1024*1024);
+ fd_kernel = udev_monitor_get_fd(kernel_monitor);
+
+ udev_list_entry_foreach(entry, udev_list_get_entry(&subsystem_match_list)) {
+ const char *subsys = udev_list_entry_get_name(entry);
+
+ if (udev_monitor_filter_add_match_subsystem_devtype(kernel_monitor, subsys, NULL) < 0)
+ fprintf(stderr, "error: unable to apply subsystem filter '%s'\n", subsys);
+ }
+
+ if (udev_monitor_enable_receiving(kernel_monitor) < 0) {
+ fprintf(stderr, "error: unable to subscribe to kernel events\n");
+ return 4;
+ }
+
+ memzero(&ep_kernel, sizeof(struct epoll_event));
+ ep_kernel.events = EPOLLIN;
+ ep_kernel.data.fd = fd_kernel;
+ if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_kernel, &ep_kernel) < 0) {
+ log_error_errno(errno, "fail to add fd to epoll: %m");
+ return 5;
+ }
+
+ printf("KERNEL - the kernel uevent\n");
+ }
+ printf("\n");
+
+ while (!udev_exit) {
+ int fdcount;
+ struct epoll_event ev[4];
+ int i;
+
+ fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), -1);
+ if (fdcount < 0) {
+ if (errno != EINTR)
+ fprintf(stderr, "error receiving uevent message: %m\n");
+ continue;
+ }
+
+ for (i = 0; i < fdcount; i++) {
+ if (ev[i].data.fd == fd_kernel && ev[i].events & EPOLLIN) {
+ struct udev_device *device;
+
+ device = udev_monitor_receive_device(kernel_monitor);
+ if (device == NULL)
+ continue;
+ print_device(device, "KERNEL", prop);
+ udev_device_unref(device);
+ } else if (ev[i].data.fd == fd_udev && ev[i].events & EPOLLIN) {
+ struct udev_device *device;
+
+ device = udev_monitor_receive_device(udev_monitor);
+ if (device == NULL)
+ continue;
+ print_device(device, "UDEV", prop);
+ udev_device_unref(device);
+ }
+ }
+ }
+
+ return 0;
+}
+
+const struct udevadm_cmd udevadm_monitor = {
+ .name = "monitor",
+ .cmd = adm_monitor,
+ .help = "Listen to kernel and udev events",
+};