config/chroot_local-includes/usr/src/udev-watchdog.c

   1 /*
   2  * Copyright (C) 2004-2009 Kay Sievers <kay.sievers@vrfy.org>
   3  *
   4  * + Trimmed from udev-149. Fixed passing of devtype parameter.
   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 #ifndef _POSIX_C_SOURCE
  21 #define _POSIX_C_SOURCE 1
  22 #ifndef _BSD_SOURCE
  23 #define _BSD_SOURCE
  24 #endif
  25 #endif
  26
  27 #include <unistd.h>
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <stddef.h>
  31 #include <string.h>
  32 #include <fcntl.h>
  33 #include <errno.h>
  34 #include <signal.h>
  35 #include <getopt.h>
  36 #include <sys/time.h>
  37 #include <sys/socket.h>
  38 #include <sys/un.h>
  39 #include <sys/select.h>
  40 #include <linux/types.h>
  41 #include <linux/netlink.h>
  42 #include <libudev.h>
  43
  44 static volatile sig_atomic_t udev_exit;
  45
  46 static void sig_handler(int signum)
  47 {
  48         if (signum == SIGINT || signum == SIGTERM)
  49                 udev_exit = 2;
  50 }
  51
  52 static int print_device(struct udev_device *device, const char *f_action, const char *f_devsuffix)
  53 {
  54         struct timeval  tv;
  55
  56     const  char *action  = udev_device_get_action(device);
  57     const  char *devpath = udev_device_get_devpath(device);
  58     size_t f_len, d_len;
  59
  60         gettimeofday(&tv, NULL);
  61         printf("%lu.%06u %s %s\n",
  62                (unsigned long) tv.tv_sec, (unsigned int) tv.tv_usec,
  63                action, devpath);
  64
  65     if (! strcmp(f_action, action)) {
  66         f_len = strlen(f_devsuffix);
  67         d_len = strlen(devpath);
  68
  69         if (d_len >= f_len && !strcmp(devpath+(d_len-f_len), f_devsuffix))
  70             return 1;
  71     }
  72
  73     return 0;
  74 }
  75
  76 int main(int argc, char *argv[])
  77 {
  78         int rc = 0;
  79
  80         struct udev *udev;
  81
  82         struct sigaction act;
  83         sigset_t mask;
  84         struct udev_monitor *kernel_monitor = NULL;
  85         fd_set readfds;
  86
  87         const char *filter_subsys    = "block";
  88         /* const char *filter_devtype   = "partition"; */
  89         const char *filter_devsuffix;
  90         const char *filter_devtype;
  91         const char *filter_action;
  92
  93         udev = udev_new();
  94         if (udev == NULL)
  95                 goto out2;
  96
  97         if (argc != 3)
  98                 goto out2;
  99
 100         filter_devsuffix = argv[1];
 101         filter_devtype = argv[2];
 102
 103         if (strcmp(filter_devtype, "cd") == 0) {
 104                 filter_action = "change";
 105         } else if (strcmp(filter_devtype, "disk") == 0) {
 106                 filter_action = "remove";
 107         }
 108
 109         /* set signal handlers */
 110         memset(&act, 0x00, sizeof(struct sigaction));
 111         act.sa_handler = sig_handler;
 112         sigemptyset(&act.sa_mask);
 113         act.sa_flags = SA_RESTART;
 114         sigaction(SIGINT, &act, NULL);
 115         sigaction(SIGTERM, &act, NULL);
 116         sigemptyset(&mask);
 117         sigaddset(&mask, SIGINT);
 118         sigaddset(&mask, SIGTERM);
 119         sigprocmask(SIG_UNBLOCK, &mask, NULL);
 120
 121         kernel_monitor = udev_monitor_new_from_netlink(udev, "kernel");
 122         if (kernel_monitor == NULL) {
 123                 fprintf(stderr, "error: unable to create netlink socket\n");
 124                 rc = 3;
 125                 goto out;
 126         }
 127
 128         if (udev_monitor_filter_add_match_subsystem_devtype(kernel_monitor, filter_subsys, NULL /* filter_devtype */) < 0)
 129                 fprintf(stderr, "error: unable to apply subsystem filter '%s:%s'\n", filter_subsys, "NULL" /* filter_devtype */);
 130
 131         if (udev_monitor_enable_receiving(kernel_monitor) < 0) {
 132                 fprintf(stderr, "error: unable to subscribe to kernel events\n");
 133                 rc = 4;
 134                 goto out;
 135         }
 136
 137         while (!udev_exit) {
 138                 int fdcount;
 139
 140                 FD_ZERO(&readfds);
 141                 if (kernel_monitor != NULL)
 142                         FD_SET(udev_monitor_get_fd(kernel_monitor), &readfds);
 143
 144                 fdcount = select(udev_monitor_get_fd(kernel_monitor)+1,
 145                                  &readfds, NULL, NULL, NULL);
 146                 if (fdcount < 0) {
 147                         if (errno != EINTR)
 148                                 fprintf(stderr, "error receiving uevent message: %s\n", strerror(errno));
 149                         continue;
 150                 }
 151
 152                 if ((kernel_monitor != NULL) && FD_ISSET(udev_monitor_get_fd(kernel_monitor), &readfds)) {
 153                         struct udev_device *device;
 154
 155                         device = udev_monitor_receive_device(kernel_monitor);
 156                         if (device == NULL)
 157                                 continue;
 158                         if (print_device(device, filter_action, filter_devsuffix))
 159                 udev_exit = 1;
 160
 161                         udev_device_unref(device);
 162                 }
 163         }
 164
 165 out:
 166         udev_monitor_unref(kernel_monitor);
 167
 168 out2:
 169         udev_unref(udev);
 170
 171     if (udev_exit == 2)
 172         rc = 1;
 173
 174         return rc;
 175 }