chiark / gitweb /
make rename_netif() error messages useful
[elogind.git] / udev_device.c
index 781787ef4ac5149e404842aa7b6830695a72b789..87f90c76769b714320381368ab9cf02649c2030e 100644 (file)
@@ -1,7 +1,7 @@
 /*
- * udev_utils.c - generic stuff used by udev
+ * udev_device.c - main udev data object
  *
- * Copyright (C) 2004, 2005 Kay Sievers <kay.sievers@vrfy.org>
+ * Copyright (C) 2004-2006 Kay Sievers <kay.sievers@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
 #include <fcntl.h>
 #include <errno.h>
 #include <ctype.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <net/if.h>
+#include <linux/sockios.h>
 
 #include "udev.h"
 #include "udev_rules.h"
@@ -77,50 +81,194 @@ dev_t udev_device_get_devt(struct udevice *udev)
        return makedev(0, 0);
 }
 
+static int rename_netif(struct udevice *udev)
+{
+       int sk;
+       struct ifreq ifr;
+       int retval;
+
+       info("changing net interface name from '%s' to '%s'", udev->dev->kernel_name, udev->name);
+       if (udev->test_run)
+               return 0;
+
+       sk = socket(PF_INET, SOCK_DGRAM, 0);
+       if (sk < 0) {
+               err("error opening socket: %s", strerror(errno));
+               return -1;
+       }
+
+       memset(&ifr, 0x00, sizeof(struct ifreq));
+       strlcpy(ifr.ifr_name, udev->dev->kernel_name, IFNAMSIZ);
+       strlcpy(ifr.ifr_newname, udev->name, IFNAMSIZ);
+       retval = ioctl(sk, SIOCSIFNAME, &ifr);
+       if (retval != 0) {
+               int loop;
+
+               /* see if the destination interface name already exists */
+               if (errno != EEXIST) {
+                       err("error changing netif name %s to %s: %s", ifr.ifr_name, ifr.ifr_newname, strerror(errno));
+                       goto exit;
+               }
+
+               /* free our own name, another process may wait for us */
+               strlcpy(ifr.ifr_newname, udev->dev->kernel_name, IFNAMSIZ);
+               strlcat(ifr.ifr_newname, "_rename", IFNAMSIZ);
+               retval = ioctl(sk, SIOCSIFNAME, &ifr);
+               if (retval != 0) {
+                       err("error changing netif name %s to %s: %s", ifr.ifr_name, ifr.ifr_newname, strerror(errno));
+                       goto exit;
+               }
+
+               /* wait 30 seconds for our target to become available */
+               strlcpy(ifr.ifr_name, ifr.ifr_newname, IFNAMSIZ);
+               strlcpy(ifr.ifr_newname, udev->name, IFNAMSIZ);
+               loop = 30 * 20;
+               while (loop--) {
+                       retval = ioctl(sk, SIOCSIFNAME, &ifr);  
+                       if (retval != 0) {
+                               if (errno != EEXIST) {
+                                       err("error changing net interface name %s to %s: %s",
+                                           ifr.ifr_name, ifr.ifr_newname, strerror(errno));
+                                       break;
+                               }
+                               dbg("wait for netif '%s' to become free, loop=%i", udev->name, (30 * 20) - loop);
+                               usleep(1000 * 1000 / 20);
+                       }
+               }
+       }
+
+exit:
+       close(sk);
+       return retval;
+}
+
 int udev_device_event(struct udev_rules *rules, struct udevice *udev)
 {
        int retval = 0;
 
-       /* device node or netif */
-       if ((major(udev->devt) != 0 || strcmp(udev->dev->subsystem, "net") == 0) &&
-           strcmp(udev->action, "add") == 0) {
-               dbg("device node or netif add '%s'", udev->dev->devpath);
+       /* add device node */
+       if (major(udev->devt) != 0 &&
+           (strcmp(udev->action, "add") == 0 || strcmp(udev->action, "change") == 0)) {
+               struct udevice *udev_old;
+
+               dbg("device node add '%s'", udev->dev->devpath);
+
                udev_rules_get_name(rules, udev);
                if (udev->ignore_device) {
                        info("device event will be ignored");
-                       return -1;
+                       goto exit;
                }
-               /* create node, store in db */
-               if (udev->name[0] != '\0')
-                       retval = udev_add_device(udev);
-               else
+               if (udev->name[0] == '\0') {
                        info("device node creation supressed");
-               return 0;
+                       goto exit;
+               }
+
+               /* read current database entry, we may want to cleanup symlinks */
+               udev_old = udev_device_init();
+               if (udev_old != NULL) {
+                       if (udev_db_get_device(udev_old, udev->dev->devpath) != 0) {
+                               udev_device_cleanup(udev_old);
+                               udev_old = NULL;
+                       } else
+                               info("device '%s' already in database, validate currently present symlinks",
+                                    udev->dev->devpath);
+               }
+
+               /* create node and symlinks */
+               retval = udev_node_add(udev, udev_old);
+               if (retval == 0) {
+                       /* store record in database */
+                       udev_db_add_device(udev);
+
+                       /* remove possibly left-over symlinks */
+                       if (udev_old != NULL) {
+                               struct name_entry *link_loop;
+                               struct name_entry *link_old_loop;
+                               struct name_entry *link_old_tmp_loop;
+
+                               /* remove still valid symlinks from old list */
+                               list_for_each_entry_safe(link_old_loop, link_old_tmp_loop, &udev_old->symlink_list, node)
+                                       list_for_each_entry(link_loop, &udev->symlink_list, node)
+                                               if (strcmp(link_old_loop->name, link_loop->name) == 0) {
+                                                       dbg("symlink '%s' still valid, keep it", link_old_loop->name);
+                                                       list_del(&link_old_loop->node);
+                                                       free(link_old_loop);
+                                               }
+                               udev_node_remove_symlinks(udev_old);
+                               udev_device_cleanup(udev_old);
+                       }
+               }
+               goto exit;
+       }
+
+       /* add netif */
+       if (strcmp(udev->dev->subsystem, "net") == 0 && strcmp(udev->action, "add") == 0) {
+               dbg("netif add '%s'", udev->dev->devpath);
+               udev_rules_get_name(rules, udev);
+               if (udev->ignore_device) {
+                       info("device event will be ignored");
+                       goto exit;
+               }
+
+               /* look if we want to change the name of the netif */
+               if (strcmp(udev->name, udev->dev->kernel_name) != 0) {
+                       char *pos;
+
+                       retval = rename_netif(udev);
+                       if (retval != 0)
+                               goto exit;
+                       info("renamed netif to '%s'", udev->name);
+
+                       /* export old name */
+                       setenv("INTERFACE_OLD", udev->dev->kernel_name, 1);
+
+                       /* now fake the devpath, because the kernel name changed silently */
+                       pos = strrchr(udev->dev->devpath, '/');
+                       if (pos != NULL) {
+                               pos[1] = '\0';
+                               strlcat(udev->dev->devpath, udev->name, sizeof(udev->dev->devpath));
+                               strlcpy(udev->dev->kernel_name, udev->name, sizeof(udev->dev->kernel_name));
+                               setenv("DEVPATH", udev->dev->devpath, 1);
+                               setenv("INTERFACE", udev->name, 1);
+                       }
+               }
+               goto exit;
        }
 
+       /* remove device node */
        if (major(udev->devt) != 0 && strcmp(udev->action, "remove") == 0) {
                struct name_entry *name_loop;
 
+               /* import and delete database entry */
+               if (udev_db_get_device(udev, udev->dev->devpath) == 0) {
+                       udev_db_delete_device(udev);
+                       if (udev->ignore_remove) {
+                               dbg("remove event for '%s' requested to be ignored by rule", udev->name);
+                               return 0;
+                       }
+                       /* restore stored persistent data */
+                       list_for_each_entry(name_loop, &udev->env_list, node)
+                               putenv(name_loop->name);
+               } else {
+                       dbg("'%s' not found in database, using kernel name '%s'", udev->dev->devpath, udev->dev->kernel_name);
+                       strlcpy(udev->name, udev->dev->kernel_name, sizeof(udev->name));
+               }
+
                udev_rules_get_run(rules, udev);
                if (udev->ignore_device) {
                        info("device event will be ignored");
-                       return -1;
+                       goto exit;
                }
-               /* get data from db, remove db-entry, delete node */
-               retval = udev_remove_device(udev);
 
-               /* restore stored persistent data */
-               list_for_each_entry(name_loop, &udev->env_list, node)
-                       putenv(name_loop->name);
-               return 0;
+               retval = udev_node_remove(udev);
+               goto exit;
        }
 
        /* default devices */
        udev_rules_get_run(rules, udev);
-       if (udev->ignore_device) {
+       if (udev->ignore_device)
                info("device event will be ignored");
-               return -1;
-       }
 
+exit:
        return retval;
 }