udev_event.c

   1 /*
   2  * udev_event.c - udev event process
   3  *
   4  * Copyright (C) 2004, 2005 Kay Sievers <kay.sievers@vrfy.org>
   5  *
   6  *      This program is free software; you can redistribute it and/or modify it
   7  *      under the terms of the GNU General Public License as published by the
   8  *      Free Software Foundation version 2 of the License.
   9  *
  10  *      This program is distributed in the hope that it will be useful, but
  11  *      WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  *      General Public License for more details.
  14  *
  15  *      You should have received a copy of the GNU General Public License along
  16  *      with this program; if not, write to the Free Software Foundation, Inc.,
  17  *      675 Mass Ave, Cambridge, MA 02139, USA.
  18  *
  19  */
  20
  21
  22 #include <stdlib.h>
  23 #include <stdio.h>
  24 #include <stddef.h>
  25 #include <unistd.h>
  26 #include <fcntl.h>
  27 #include <errno.h>
  28 #include <ctype.h>
  29 #include <dirent.h>
  30 #include <syslog.h>
  31
  32 #include "udev_libc_wrapper.h"
  33 #include "udev.h"
  34 #include "logging.h"
  35 #include "udev_rules.h"
  36 #include "udev_utils.h"
  37 #include "udev_sysfs.h"
  38 #include "list.h"
  39
  40
  41 int udev_process_event(struct udev_rules *rules, struct udevice *udev)
  42 {
  43         int retval;
  44         char path[PATH_SIZE];
  45         const char *error;
  46
  47         if (udev->type == DEV_BLOCK || udev->type == DEV_CLASS || udev->type == DEV_NET) {
  48                 /* handle device node */
  49                 if (strcmp(udev->action, "add") == 0) {
  50                         struct sysfs_class_device *class_dev;
  51
  52                         /* wait for sysfs of /sys/class /sys/block */
  53                         dbg("node add");
  54                         snprintf(path, sizeof(path), "%s%s", sysfs_path, udev->devpath);
  55                         path[sizeof(path)-1] = '\0';
  56                         class_dev = wait_class_device_open(path);
  57                         if (class_dev == NULL) {
  58                                 dbg("open class device failed");
  59                                 return 0;
  60                         }
  61                         dbg("opened class_dev->name='%s'", class_dev->name);
  62                         wait_for_class_device(class_dev, &error);
  63
  64                         /* get major/minor */
  65                         if (udev->type == DEV_BLOCK || udev->type == DEV_CLASS)
  66                                 udev->devt = get_devt(class_dev);
  67
  68                         if (udev->type == DEV_NET || udev->devt) {
  69                                 /* name device */
  70                                 udev_rules_get_name(rules, udev, class_dev);
  71                                 if (udev->ignore_device) {
  72                                         info("device event will be ignored");
  73                                         sysfs_close_class_device(class_dev);
  74                                         return -1;
  75                                 }
  76                                 if (udev->name[0] != '\0') {
  77                                         /* create node, store in db */
  78                                         retval = udev_add_device(udev, class_dev);
  79                                 } else {
  80                                         info("device node creation supressed");
  81                                 }
  82                         } else {
  83                                 dbg("no dev-file found");
  84                                 udev_rules_get_run(rules, udev, class_dev, NULL);
  85                                 if (udev->ignore_device) {
  86                                         info("device event will be ignored");
  87                                         sysfs_close_class_device(class_dev);
  88                                         return -1;
  89                                 }
  90                         }
  91                         sysfs_close_class_device(class_dev);
  92                 } else if (strcmp(udev->action, "remove") == 0) {
  93                         struct name_entry *name_loop;
  94
  95                         /* get data from db, remove db-entry, delete node */
  96                         dbg("node remove");
  97                         retval = udev_remove_device(udev);
  98
  99                         /* restore stored persistent data */
 100                         list_for_each_entry(name_loop, &udev->env_list, node)
 101                                 putenv(name_loop->name);
 102
 103                         udev_rules_get_run(rules, udev, NULL, NULL);
 104                         if (udev->ignore_device) {
 105                                 dbg("device event will be ignored");
 106                                 return -1;
 107                         }
 108                 }
 109
 110                 /* export name of device node or netif */
 111                 if (udev->devname[0] != '\0')
 112                         setenv("DEVNAME", udev->devname, 1);
 113         } else if (udev->type == DEV_DEVICE && strcmp(udev->action, "add") == 0) {
 114                 struct sysfs_device *devices_dev;
 115
 116                 /* wait for sysfs of /sys/devices/ */
 117                 dbg("devices add");
 118                 snprintf(path, sizeof(path), "%s%s", sysfs_path, udev->devpath);
 119                 path[sizeof(path)-1] = '\0';
 120                 devices_dev = wait_devices_device_open(path);
 121                 if (!devices_dev) {
 122                         dbg("devices device unavailable (probably remove has beaten us)");
 123                         return 0;
 124                 }
 125                 dbg("devices device opened '%s'", path);
 126                 wait_for_devices_device(devices_dev, &error);
 127                 udev_rules_get_run(rules, udev, NULL, devices_dev);
 128                 sysfs_close_device(devices_dev);
 129                 if (udev->ignore_device) {
 130                         info("device event will be ignored");
 131                         return -1;
 132                 }
 133         } else {
 134                 dbg("default handling");
 135                 udev_rules_get_run(rules, udev, NULL, NULL);
 136                 if (udev->ignore_device) {
 137                         info("device event will be ignored");
 138                         return -1;
 139                 }
 140         }
 141         return 0;
 142 }