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Diffstat (limited to 'udev_node.c')
-rw-r--r--udev_node.c235
1 files changed, 133 insertions, 102 deletions
diff --git a/udev_node.c b/udev_node.c
index 1558df849c..526d713516 100644
--- a/udev_node.c
+++ b/udev_node.c
@@ -25,6 +25,7 @@
#include <unistd.h>
#include <errno.h>
#include <grp.h>
+#include <dirent.h>
#include <sys/stat.h>
#include <sys/types.h>
@@ -114,7 +115,7 @@ static int node_symlink(const char *node, const char *slink)
if (len > 0) {
buf[len] = '\0';
if (strcmp(target, buf) == 0) {
- info("preserving symlink '%s' to '%s'", slink, target);
+ info("preserve already existing symlink '%s' to '%s'", slink, target);
selinux_setfilecon(slink, NULL, S_IFLNK);
goto exit;
}
@@ -133,7 +134,131 @@ exit:
return 0;
}
-int udev_node_add(struct udevice *udev, struct udevice *udev_old)
+static int update_link(struct udevice *udev, const char *name)
+{
+ LIST_HEAD(name_list);
+ char slink[PATH_SIZE];
+ char node[PATH_SIZE];
+ struct udevice *udev_db;
+ struct name_entry *device;
+ char target[PATH_MAX] = "";
+ int count;
+ int priority = 0;
+ int rc = 0;
+
+ strlcpy(slink, udev_root, sizeof(slink));
+ strlcat(slink, "/", sizeof(slink));
+ strlcat(slink, name, sizeof(slink));
+
+ count = udev_db_get_devices_by_name(name, &name_list);
+ info("found %i devices with name '%s'", count, name);
+
+ /* if we don't have any reference, we can delete the link */
+ if (count <= 0) {
+ info("no reference left, remove '%s'", name);
+ if (!udev->test_run) {
+ unlink(slink);
+ delete_path(slink);
+ }
+ goto out;
+ }
+
+ /* find the device with the highest priority */
+ list_for_each_entry(device, &name_list, node) {
+ info("found '%s' for '%s'", device->name, name);
+
+ /* did we find ourself? we win, if we have the same priority */
+ if (strcmp(udev->dev->devpath, device->name) == 0) {
+ info("compare (our own) priority of '%s' %i >= %i",
+ udev->dev->devpath, udev->link_priority, priority);
+ if (target[0] == '\0' || udev->link_priority >= priority) {
+ priority = udev->link_priority;
+ strlcpy(target, udev->name, sizeof(target));
+ }
+ continue;
+ }
+
+ /* or something else, then read priority from database */
+ udev_db = udev_device_init(NULL);
+ if (udev_db == NULL)
+ continue;
+ if (udev_db_get_device(udev_db, device->name) == 0) {
+ info("compare priority of '%s' %i > %i",
+ udev_db->dev->devpath, udev_db->link_priority, priority);
+ if (target[0] == '\0' || udev_db->link_priority > priority) {
+ priority = udev_db->link_priority;
+ strlcpy(target, udev_db->name, sizeof(target));
+ }
+ }
+ udev_device_cleanup(udev_db);
+ }
+ name_list_cleanup(&name_list);
+
+ if (target[0] == '\0') {
+ err("missing target for '%s'", name);
+ rc = -1;
+ goto out;
+ }
+
+ /* create symlink to the target with the highest priority */
+ strlcpy(node, udev_root, sizeof(node));
+ strlcat(node, "/", sizeof(node));
+ strlcat(node, target, sizeof(node));
+ info("'%s' with target '%s' has the highest priority %i, create it", name, target, priority);
+ if (!udev->test_run) {
+ create_path(slink);
+ node_symlink(node, slink);
+ }
+out:
+ return rc;
+}
+
+void udev_node_update_symlinks(struct udevice *udev, struct udevice *udev_old)
+{
+ struct name_entry *name_loop;
+ char symlinks[PATH_SIZE] = "";
+
+ list_for_each_entry(name_loop, &udev->symlink_list, node) {
+ info("update symlink '%s' of '%s'", name_loop->name, udev->dev->devpath);
+ update_link(udev, name_loop->name);
+ strlcat(symlinks, udev_root, sizeof(symlinks));
+ strlcat(symlinks, "/", sizeof(symlinks));
+ strlcat(symlinks, name_loop->name, sizeof(symlinks));
+ strlcat(symlinks, " ", sizeof(symlinks));
+ }
+
+ /* export symlinks to environment */
+ remove_trailing_chars(symlinks, ' ');
+ if (symlinks[0] != '\0')
+ setenv("DEVLINKS", symlinks, 1);
+
+ /* update possible left-over symlinks (device metadata changed) */
+ if (udev_old != NULL) {
+ struct name_entry *link_loop;
+ struct name_entry *link_old_loop;
+ struct name_entry *link_old_tmp_loop;
+ int found;
+
+ /* remove current symlinks from old list */
+ list_for_each_entry_safe(link_old_loop, link_old_tmp_loop, &udev_old->symlink_list, node) {
+ found = 0;
+ list_for_each_entry(link_loop, &udev->symlink_list, node) {
+ if (strcmp(link_old_loop->name, link_loop->name) == 0) {
+ found = 1;
+ break;
+ }
+ }
+ if (!found) {
+ /* link does no longer belong to this device */
+ info("update old symlink '%s' no longer belonging to '%s'",
+ link_old_loop->name, udev->dev->devpath);
+ update_link(udev, link_old_loop->name);
+ }
+ }
+ }
+}
+
+int udev_node_add(struct udevice *udev)
{
char filename[PATH_SIZE];
uid_t uid;
@@ -141,10 +266,9 @@ int udev_node_add(struct udevice *udev, struct udevice *udev_old)
int i;
int retval = 0;
- snprintf(filename, sizeof(filename), "%s/%s", udev_root, udev->name);
- filename[sizeof(filename)-1] = '\0';
-
- /* create parent directories if needed */
+ strlcpy(filename, udev_root, sizeof(filename));
+ strlcat(filename, "/", sizeof(filename));
+ strlcat(filename, udev->name, sizeof(filename));
create_path(filename);
if (strcmp(udev->owner, "root") == 0)
@@ -209,102 +333,10 @@ int udev_node_add(struct udevice *udev, struct udevice *udev_old)
}
}
}
-
- /* create symlink(s) if requested */
- if (!list_empty(&udev->symlink_list)) {
- struct name_entry *name_loop;
- char symlinks[PATH_SIZE] = "";
-
- list_for_each_entry(name_loop, &udev->symlink_list, node) {
- char slink[PATH_SIZE];
-
- strlcpy(slink, udev_root, sizeof(slink));
- strlcat(slink, "/", sizeof(slink));
- strlcat(slink, name_loop->name, sizeof(slink));
-
- info("creating symlink '%s' to node '%s'", slink, filename);
- if (!udev->test_run) {
- create_path(slink);
- node_symlink(filename, slink);
- }
-
- strlcat(symlinks, slink, sizeof(symlinks));
- strlcat(symlinks, " ", sizeof(symlinks));
- }
-
- remove_trailing_chars(symlinks, ' ');
- setenv("DEVLINKS", symlinks, 1);
- }
-
exit:
return retval;
}
-void udev_node_remove_symlinks(struct udevice *udev)
-{
- char filename[PATH_SIZE];
- struct name_entry *name_loop;
- struct stat stats;
-
- if (!list_empty(&udev->symlink_list)) {
- char symlinks[PATH_SIZE] = "";
-
- list_for_each_entry(name_loop, &udev->symlink_list, node) {
- char devpath[PATH_SIZE];
-
- snprintf(filename, sizeof(filename), "%s/%s", udev_root, name_loop->name);
- filename[sizeof(filename)-1] = '\0';
-
- if (stat(filename, &stats) != 0) {
- dbg("symlink '%s' not found", filename);
- continue;
- }
- if (udev->devt && stats.st_rdev != udev->devt) {
- info("symlink '%s' points to a different device, skip removal", filename);
- continue;
- }
-
- info("removing symlink '%s'", filename);
- if (!udev->test_run) {
- unlink(filename);
- delete_path(filename);
- }
-
- /* see if another device wants this symlink */
- if (udev_db_lookup_name(name_loop->name, devpath, sizeof(devpath)) == 0) {
- struct udevice *old;
-
- info("found overwritten symlink '%s' of '%s'", name_loop->name, devpath);
- old = udev_device_init(NULL);
- if (old != NULL) {
- if (udev_db_get_device(old, devpath) == 0) {
- char slink[PATH_SIZE];
- char node[PATH_SIZE];
-
- strlcpy(slink, udev_root, sizeof(slink));
- strlcat(slink, "/", sizeof(slink));
- strlcat(slink, name_loop->name, sizeof(slink));
- strlcpy(node, udev_root, sizeof(node));
- strlcat(node, "/", sizeof(node));
- strlcat(node, old->name, sizeof(node));
- info("restore symlink '%s' to '%s'", slink, node);
- if (!udev->test_run)
- node_symlink(node, slink);
- }
- udev_device_cleanup(old);
- }
- }
-
- strlcat(symlinks, filename, sizeof(symlinks));
- strlcat(symlinks, " ", sizeof(symlinks));
- }
-
- remove_trailing_chars(symlinks, ' ');
- if (symlinks[0] != '\0')
- setenv("DEVLINKS", symlinks, 1);
- }
-}
-
int udev_node_remove(struct udevice *udev)
{
char filename[PATH_SIZE];
@@ -313,10 +345,9 @@ int udev_node_remove(struct udevice *udev)
int retval;
int num;
- udev_node_remove_symlinks(udev);
-
- snprintf(filename, sizeof(filename), "%s/%s", udev_root, udev->name);
- filename[sizeof(filename)-1] = '\0';
+ strlcpy(filename, udev_root, sizeof(filename));
+ strlcat(filename, "/", sizeof(filename));
+ strlcat(filename, udev->name, sizeof(filename));
if (stat(filename, &stats) != 0) {
dbg("device node '%s' not found", filename);
return -1;
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-12-29 14:40:00 +0000