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-rw-r--r--udev/udev-node.c241
1 files changed, 84 insertions, 157 deletions
diff --git a/udev/udev-node.c b/udev/udev-node.c
index 36f6f6d993..f17c48a7b4 100644
--- a/udev/udev-node.c
+++ b/udev/udev-node.c
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2003-2008 Kay Sievers <kay.sievers@vrfy.org>
+ * Copyright (C) 2003-2009 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
@@ -19,6 +19,7 @@
#include <string.h>
#include <stdio.h>
#include <stddef.h>
+#include <stdbool.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
@@ -31,29 +32,6 @@
#define TMP_FILE_EXT ".udev-tmp"
-/* reverse mapping from the device file name to the devpath */
-static int name_index(struct udev_device *dev, const char *name, int add)
-{
- struct udev *udev = udev_device_get_udev(dev);
- char name_enc[UTIL_PATH_SIZE];
- char filename[UTIL_PATH_SIZE * 2];
-
- util_path_encode(&name[strlen(udev_get_dev_path(udev))+1], name_enc, sizeof(name_enc));
- snprintf(filename, sizeof(filename), "%s/.udev/names/%s/%u:%u", udev_get_dev_path(udev), name_enc,
- major(udev_device_get_devnum(dev)), minor(udev_device_get_devnum(dev)));
-
- if (add) {
- dbg(udev, "creating index: '%s'\n", filename);
- util_create_path(udev, filename);
- symlink(udev_device_get_devpath(dev), filename);
- } else {
- dbg(udev, "removing index: '%s'\n", filename);
- unlink(filename);
- util_delete_path(udev, filename);
- }
- return 0;
-}
-
int udev_node_mknod(struct udev_device *dev, const char *file, dev_t devnum, mode_t mode, uid_t uid, gid_t gid)
{
struct udev *udev = udev_device_get_udev(dev);
@@ -168,7 +146,7 @@ static int node_symlink(struct udev *udev, const char *node, const char *slink)
info(udev, "found existing node instead of symlink '%s'\n", slink);
if (lstat(node, &stats2) == 0) {
if ((stats.st_mode & S_IFMT) == (stats2.st_mode & S_IFMT) &&
- stats.st_rdev == stats2.st_rdev) {
+ stats.st_rdev == stats2.st_rdev && stats.st_ino != stats2.st_ino) {
info(udev, "replace device node '%s' with symlink to our node '%s'\n",
slink, node);
} else {
@@ -222,143 +200,115 @@ exit:
return err;
}
-static int name_index_get_devices(struct udev *udev, const char *name, struct udev_list_node *dev_list)
+/* find device node of device with highest priority */
+static const char *link_find_prioritized(struct udev_device *dev, bool add, const char *stackdir, char *buf, size_t bufsize)
{
- char dirname[UTIL_PATH_SIZE];
- char *s;
- size_t l;
+ struct udev *udev = udev_device_get_udev(dev);
DIR *dir;
- int count = 0;
-
- s = dirname;
- l = util_strpcpyl(&s, sizeof(dirname), udev_get_dev_path(udev),
- "/.udev/names/", NULL);
- util_path_encode(&name[strlen(udev_get_dev_path(udev))+1], s, l);
- dir = opendir(dirname);
- if (dir == NULL) {
- dbg(udev, "no index directory '%s': %m\n", dirname);
- count = -1;
- goto out;
+ int priority = 0;
+ const char *target = NULL;
+
+ if (add) {
+ priority = udev_device_get_devlink_priority(dev);
+ util_strscpy(buf, bufsize, udev_device_get_devnode(dev));
+ target = buf;
}
- dbg(udev, "found index directory '%s'\n", dirname);
- while (1) {
+ dir = opendir(stackdir);
+ if (dir == NULL)
+ return target;
+ for (;;) {
+ struct udev_device *dev_db;
struct dirent *dent;
char devpath[UTIL_PATH_SIZE];
char syspath[UTIL_PATH_SIZE];
- int len;
+ ssize_t len;
dent = readdir(dir);
if (dent == NULL || dent->d_name[0] == '\0')
break;
if (dent->d_name[0] == '.')
continue;
-
+ dbg(udev, "found '%s/%s'\n", stackdir, dent->d_name);
len = readlinkat(dirfd(dir), dent->d_name, devpath, sizeof(devpath));
- if (len < 0 || (size_t)len >= sizeof(devpath))
+ if (len <= 0 || len == (ssize_t)sizeof(devpath))
continue;
devpath[len] = '\0';
util_strscpyl(syspath, sizeof(syspath), udev_get_sys_path(udev), devpath, NULL);
- udev_list_entry_add(udev, dev_list, syspath, NULL, 1, 0);
- count++;
+ info(udev, "found '%s' claiming '%s'\n", syspath, stackdir);
+
+ /* did we find ourself? */
+ if (strcmp(udev_device_get_syspath(dev), syspath) == 0)
+ continue;
+
+ dev_db = udev_device_new_from_syspath(udev, syspath);
+ if (dev_db != NULL) {
+ const char *devnode;
+
+ devnode = udev_device_get_devnode(dev_db);
+ if (devnode != NULL) {
+ dbg(udev, "compare priority of '%s'(%i) > '%s'(%i)\n", target, priority,
+ udev_device_get_devnode(dev_db), udev_device_get_devlink_priority(dev_db));
+ if (target == NULL || udev_device_get_devlink_priority(dev_db) > priority) {
+ info(udev, "'%s' claims priority %i for '%s'\n",
+ syspath, udev_device_get_devlink_priority(dev_db), stackdir);
+ priority = udev_device_get_devlink_priority(dev_db);
+ util_strscpy(buf, bufsize, devnode);
+ target = buf;
+ }
+ }
+ udev_device_unref(dev_db);
+ }
}
- closedir(dir);
-out:
- return count;
+ return target;
}
-static int update_link(struct udev_device *dev, const char *slink)
+/* manage "stack of names" with possibly specified device priorities */
+static void link_update(struct udev_device *dev, const char *slink, bool add)
{
struct udev *udev = udev_device_get_udev(dev);
- struct udev_list_node dev_list;
- struct udev_list_entry *dev_entry;
- char target[UTIL_PATH_SIZE];
- int count;
- int priority = 0;
- int rc = 0;
+ char name_enc[UTIL_PATH_SIZE];
+ char filename[UTIL_PATH_SIZE * 2];
+ char dirname[UTIL_PATH_SIZE];
+ const char *target;
+ char buf[UTIL_PATH_SIZE];
dbg(udev, "update symlink '%s' of '%s'\n", slink, udev_device_get_syspath(dev));
- udev_list_init(&dev_list);
- count = name_index_get_devices(udev, slink, &dev_list);
- if (count > 1)
- info(udev, "found %i devices with name '%s'\n", count, slink);
+ util_path_encode(&slink[strlen(udev_get_dev_path(udev))+1], name_enc, sizeof(name_enc));
+ snprintf(dirname, sizeof(dirname), "%s/.udev/links/%s", udev_get_dev_path(udev), name_enc);
+ snprintf(filename, sizeof(filename), "%s/%c%u:%u", dirname,
+ strcmp(udev_device_get_subsystem(dev), "block") == 0 ? 'b' : 'c',
+ major(udev_device_get_devnum(dev)), minor(udev_device_get_devnum(dev)));
+
+ if (!add) {
+ dbg(udev, "removing index: '%s'\n", filename);
+ unlink(filename);
+ util_delete_path(udev, filename);
+ }
- /* if we don't have a reference, delete it */
- if (count <= 0) {
+ target = link_find_prioritized(dev, add, dirname, buf, sizeof(buf));
+ if (target == NULL) {
info(udev, "no reference left, remove '%s'\n", slink);
unlink(slink);
util_delete_path(udev, slink);
- goto out;
- }
-
- /* find the device with the highest priority */
- target[0] = '\0';
- udev_list_entry_foreach(dev_entry, udev_list_get_entry(&dev_list)) {
- const char *syspath;
- struct udev_device *dev_db;
- const char *devnode;
-
- syspath = udev_list_entry_get_name(dev_entry);
- dbg(udev, "found '%s' for '%s'\n", syspath, slink);
-
- /* did we find ourself? we win, if we have the same priority */
- if (strcmp(udev_device_get_syspath(dev), syspath) == 0) {
- dbg(udev, "compare (our own) priority of '%s' %i >= %i\n",
- udev_device_get_devpath(dev), udev_device_get_devlink_priority(dev), priority);
- if (strcmp(udev_device_get_devnode(dev), slink) == 0) {
- info(udev, "'%s' is our device node, database inconsistent, skip link update\n",
- udev_device_get_devnode(dev));
- } else if (target[0] == '\0' || udev_device_get_devlink_priority(dev) >= priority) {
- priority = udev_device_get_devlink_priority(dev);
- util_strscpy(target, sizeof(target), udev_device_get_devnode(dev));
- }
- continue;
- }
-
- /* another device, read priority from database */
- dev_db = udev_device_new_from_syspath(udev, syspath);
- if (dev_db == NULL)
- continue;
- devnode = udev_device_get_devnode(dev_db);
- if (devnode != NULL) {
- if (strcmp(devnode, slink) == 0) {
- info(udev, "'%s' is a device node of '%s', skip link update\n",
- devnode, syspath);
- } else {
- dbg(udev, "compare priority of '%s' %i > %i\n",
- udev_device_get_devpath(dev_db),
- udev_device_get_devlink_priority(dev_db),
- priority);
- if (target[0] == '\0' || udev_device_get_devlink_priority(dev_db) > priority) {
- priority = udev_device_get_devlink_priority(dev_db);
- util_strscpy(target, sizeof(target), devnode);
- }
- }
- }
- udev_device_unref(dev_db);
+ } else {
+ util_create_path(udev, slink);
+ info(udev, "creating link '%s' to '%s'\n", slink, target);
+ node_symlink(udev, target, slink);
}
- udev_list_cleanup_entries(udev, &dev_list);
- if (target[0] == '\0') {
- info(udev, "no current target for '%s' found\n", slink);
- rc = 1;
- goto out;
+ if (add) {
+ dbg(udev, "creating index: '%s'\n", filename);
+ util_create_path(udev, filename);
+ symlink(udev_device_get_devpath(dev), filename);
}
-
- /* create symlink to the target with the highest priority */
- info(udev, "'%s' with target '%s' has the highest priority %i, create it\n", slink, target, priority);
- util_create_path(udev, slink);
- node_symlink(udev, target, slink);
-out:
- return rc;
}
void udev_node_update_old_links(struct udev_device *dev, struct udev_device *dev_old)
{
struct udev *udev = udev_device_get_udev(dev);
struct udev_list_entry *list_entry;
- const char *devnode_old;
/* update possible left-over symlinks */
udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev_old)) {
@@ -366,10 +316,6 @@ void udev_node_update_old_links(struct udev_device *dev, struct udev_device *dev
struct udev_list_entry *list_entry_current;
int found;
- /* check if old link name is now our node name */
- if (strcmp(name, udev_device_get_devnode(dev)) == 0)
- continue;
-
/* check if old link name still belongs to this device */
found = 0;
udev_list_entry_foreach(list_entry_current, udev_device_get_devlinks_list_entry(dev)) {
@@ -385,23 +331,7 @@ void udev_node_update_old_links(struct udev_device *dev, struct udev_device *dev
info(udev, "update old name, '%s' no longer belonging to '%s'\n",
name, udev_device_get_devpath(dev));
- name_index(dev, name, 0);
- update_link(dev, name);
- }
-
- /*
- * if the node name has changed, delete the node,
- * and possibly restore a symlink of a different device
- */
- devnode_old = udev_device_get_devnode(dev_old);
- if (devnode_old != NULL) {
- const char *devnode = udev_device_get_devnode(dev);
-
- if (devnode != NULL && strcmp(devnode_old, devnode) != 0) {
- info(udev, "node has changed from '%s' to '%s'\n", devnode_old, devnode);
- name_index(dev, devnode_old, 0);
- update_link(dev, devnode_old);
- }
+ link_update(dev, name, 0);
}
}
@@ -441,13 +371,15 @@ int udev_node_add(struct udev_device *dev, mode_t mode, uid_t uid, gid_t gid)
}
}
- /* add node to name index */
- name_index(dev, udev_device_get_devnode(dev), 1);
-
/* create/update symlinks, add symlinks to name index */
udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev)) {
- name_index(dev, udev_list_entry_get_name(list_entry), 1);
- update_link(dev, udev_list_entry_get_name(list_entry));
+ if (udev_list_entry_get_flag(list_entry)) {
+ /* simple unmanaged link name */
+ util_create_path(udev, udev_list_entry_get_name(list_entry));
+ node_symlink(udev, udev_device_get_devnode(dev), udev_list_entry_get_name(list_entry));
+ } else {
+ link_update(dev, udev_list_entry_get_name(list_entry), 1);
+ }
}
exit:
return err;
@@ -463,14 +395,9 @@ int udev_node_remove(struct udev_device *dev)
int err = 0;
int num;
- /* remove node from name index */
- name_index(dev, udev_device_get_devnode(dev), 0);
-
/* remove,update symlinks, remove symlinks from name index */
- udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev)) {
- name_index(dev, udev_list_entry_get_name(list_entry), 0);
- update_link(dev, udev_list_entry_get_name(list_entry));
- }
+ udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev))
+ link_update(dev, udev_list_entry_get_name(list_entry), 0);
devnode = udev_device_get_devnode(dev);
if (devnode == NULL)