udev/udevadm-monitor.c

   1 /*
   2  * Copyright (C) 2004-2010 Kay Sievers <kay.sievers@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 <unistd.h>
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <stddef.h>
  22 #include <string.h>
  23 #include <fcntl.h>
  24 #include <errno.h>
  25 #include <signal.h>
  26 #include <getopt.h>
  27 #include <sys/time.h>
  28 #include <sys/socket.h>
  29 #include <sys/un.h>
  30 #include <sys/select.h>
  31 #include <linux/types.h>
  32 #include <linux/netlink.h>
  33
  34 #include "udev.h"
  35
  36 static int udev_exit;
  37
  38 static void sig_handler(int signum)
  39 {
  40         if (signum == SIGINT || signum == SIGTERM)
  41                 udev_exit = 1;
  42 }
  43
  44 static void print_device(struct udev_device *device, const char *source, int prop)
  45 {
  46         struct timeval tv;
  47         struct timezone tz;
  48
  49         gettimeofday(&tv, &tz);
  50         printf("%-6s[%llu.%06u] %-8s %s (%s)\n",
  51                source,
  52                (unsigned long long) tv.tv_sec, (unsigned int) tv.tv_usec,
  53                udev_device_get_action(device),
  54                udev_device_get_devpath(device),
  55                udev_device_get_subsystem(device));
  56         if (prop) {
  57                 struct udev_list_entry *list_entry;
  58
  59                 udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(device))
  60                         printf("%s=%s\n",
  61                                udev_list_entry_get_name(list_entry),
  62                                udev_list_entry_get_value(list_entry));
  63                 printf("\n");
  64         }
  65 }
  66
  67 int udevadm_monitor(struct udev *udev, int argc, char *argv[])
  68 {
  69         struct sigaction act;
  70         sigset_t mask;
  71         int option;
  72         int prop = 0;
  73         int print_kernel = 0;
  74         int print_udev = 0;
  75         struct udev_list_node subsystem_match_list;
  76         struct udev_list_node tag_match_list;
  77         struct udev_monitor *udev_monitor = NULL;
  78         struct udev_monitor *kernel_monitor = NULL;
  79         fd_set readfds;
  80         int rc = 0;
  81
  82         static const struct option options[] = {
  83                 { "property", no_argument, NULL, 'p' },
  84                 { "environment", no_argument, NULL, 'e' },
  85                 { "kernel", no_argument, NULL, 'k' },
  86                 { "udev", no_argument, NULL, 'u' },
  87                 { "subsystem-match", required_argument, NULL, 's' },
  88                 { "tag-match", required_argument, NULL, 't' },
  89                 { "help", no_argument, NULL, 'h' },
  90                 {}
  91         };
  92
  93         udev_list_init(&subsystem_match_list);
  94         udev_list_init(&tag_match_list);
  95         for (;;) {
  96                 option = getopt_long(argc, argv, "pekus:t:h", options, NULL);
  97                 if (option == -1)
  98                         break;
  99
 100                 switch (option) {
 101                 case 'p':
 102                 case 'e':
 103                         prop = 1;
 104                         break;
 105                 case 'k':
 106                         print_kernel = 1;
 107                         break;
 108                 case 'u':
 109                         print_udev = 1;
 110                         break;
 111                 case 's':
 112                         {
 113                                 char subsys[UTIL_NAME_SIZE];
 114                                 char *devtype;
 115
 116                                 util_strscpy(subsys, sizeof(subsys), optarg);
 117                                 devtype = strchr(subsys, '/');
 118                                 if (devtype != NULL) {
 119                                         devtype[0] = '\0';
 120                                         devtype++;
 121                                 }
 122                                 udev_list_entry_add(udev, &subsystem_match_list, subsys, devtype, 0, 0);
 123                                 break;
 124                         }
 125                 case 't':
 126                         udev_list_entry_add(udev, &tag_match_list, optarg, NULL, 0, 0);
 127                         break;
 128                 case 'h':
 129                         printf("Usage: udevadm monitor [--property] [--kernel] [--udev] [--help]\n"
 130                                "  --property                              print the event properties\n"
 131                                "  --kernel                                print kernel uevents\n"
 132                                "  --udev                                  print udev events\n"
 133                                "  --subsystem-match=<subsystem[/devtype]> filter events by subsystem\n"
 134                                "  --tag-match=<tag>                       filter events by tag\n"
 135                                "  --help\n\n");
 136                         goto out;
 137                 }
 138         }
 139
 140         if (!print_kernel && !print_udev) {
 141                 print_kernel = 1;
 142                 print_udev =1;
 143         }
 144
 145         /* set signal handlers */
 146         memset(&act, 0x00, sizeof(struct sigaction));
 147         act.sa_handler = sig_handler;
 148         sigemptyset(&act.sa_mask);
 149         act.sa_flags = SA_RESTART;
 150         sigaction(SIGINT, &act, NULL);
 151         sigaction(SIGTERM, &act, NULL);
 152         sigemptyset(&mask);
 153         sigaddset(&mask, SIGINT);
 154         sigaddset(&mask, SIGTERM);
 155         sigprocmask(SIG_UNBLOCK, &mask, NULL);
 156
 157         printf("monitor will print the received events for:\n");
 158         if (print_udev) {
 159                 struct udev_list_entry *entry;
 160
 161                 udev_monitor = udev_monitor_new_from_netlink(udev, "udev");
 162                 if (udev_monitor == NULL) {
 163                         fprintf(stderr, "error: unable to create netlink socket\n");
 164                         rc = 1;
 165                         goto out;
 166                 }
 167                 udev_monitor_set_receive_buffer_size(udev_monitor, 128*1024*1024);
 168
 169                 udev_list_entry_foreach(entry, udev_list_get_entry(&subsystem_match_list)) {
 170                         const char *subsys = udev_list_entry_get_name(entry);
 171                         const char *devtype = udev_list_entry_get_value(entry);
 172
 173                         if (udev_monitor_filter_add_match_subsystem_devtype(udev_monitor, subsys, devtype) < 0)
 174                                 fprintf(stderr, "error: unable to apply subsystem filter '%s'\n", subsys);
 175                 }
 176
 177                 udev_list_entry_foreach(entry, udev_list_get_entry(&tag_match_list)) {
 178                         const char *tag = udev_list_entry_get_name(entry);
 179
 180                         if (udev_monitor_filter_add_match_tag(udev_monitor, tag) < 0)
 181                                 fprintf(stderr, "error: unable to apply tag filter '%s'\n", tag);
 182                 }
 183
 184                 if (udev_monitor_enable_receiving(udev_monitor) < 0) {
 185                         fprintf(stderr, "error: unable to subscribe to udev events\n");
 186                         rc = 2;
 187                         goto out;
 188                 }
 189                 printf("UDEV - the event which udev sends out after rule processing\n");
 190         }
 191         if (print_kernel) {
 192                 struct udev_list_entry *entry;
 193
 194                 kernel_monitor = udev_monitor_new_from_netlink(udev, "kernel");
 195                 if (kernel_monitor == NULL) {
 196                         fprintf(stderr, "error: unable to create netlink socket\n");
 197                         rc = 3;
 198                         goto out;
 199                 }
 200                 udev_monitor_set_receive_buffer_size(kernel_monitor, 128*1024*1024);
 201
 202                 udev_list_entry_foreach(entry, udev_list_get_entry(&subsystem_match_list)) {
 203                         const char *subsys = udev_list_entry_get_name(entry);
 204
 205                         if (udev_monitor_filter_add_match_subsystem_devtype(kernel_monitor, subsys, NULL) < 0)
 206                                 fprintf(stderr, "error: unable to apply subsystem filter '%s'\n", subsys);
 207                 }
 208
 209                 if (udev_monitor_enable_receiving(kernel_monitor) < 0) {
 210                         fprintf(stderr, "error: unable to subscribe to kernel events\n");
 211                         rc = 4;
 212                         goto out;
 213                 }
 214                 printf("KERNEL - the kernel uevent\n");
 215         }
 216         printf("\n");
 217
 218         while (!udev_exit) {
 219                 int fdcount;
 220
 221                 FD_ZERO(&readfds);
 222                 if (kernel_monitor != NULL)
 223                         FD_SET(udev_monitor_get_fd(kernel_monitor), &readfds);
 224                 if (udev_monitor != NULL)
 225                         FD_SET(udev_monitor_get_fd(udev_monitor), &readfds);
 226
 227                 fdcount = select(MAX(udev_monitor_get_fd(kernel_monitor), udev_monitor_get_fd(udev_monitor))+1,
 228                                  &readfds, NULL, NULL, NULL);
 229                 if (fdcount < 0) {
 230                         if (errno != EINTR)
 231                                 fprintf(stderr, "error receiving uevent message: %m\n");
 232                         continue;
 233                 }
 234
 235                 if ((kernel_monitor != NULL) && FD_ISSET(udev_monitor_get_fd(kernel_monitor), &readfds)) {
 236                         struct udev_device *device;
 237
 238                         device = udev_monitor_receive_device(kernel_monitor);
 239                         if (device == NULL)
 240                                 continue;
 241                         print_device(device, "KERNEL", prop);
 242                         udev_device_unref(device);
 243                 }
 244
 245                 if ((udev_monitor != NULL) && FD_ISSET(udev_monitor_get_fd(udev_monitor), &readfds)) {
 246                         struct udev_device *device;
 247
 248                         device = udev_monitor_receive_device(udev_monitor);
 249                         if (device == NULL)
 250                                 continue;
 251                         print_device(device, "UDEV", prop);
 252                         udev_device_unref(device);
 253                 }
 254         }
 255
 256 out:
 257         udev_monitor_unref(udev_monitor);
 258         udev_monitor_unref(kernel_monitor);
 259         udev_list_cleanup_entries(udev, &subsystem_match_list);
 260         udev_list_cleanup_entries(udev, &tag_match_list);
 261         return rc;
 262 }