mirror of
https://github.com/systemd/systemd.git
synced 2026-08-09 01:20:53 +00:00
libudev: cache the errno for a failed parent lookup
udev_device_get_parent() caches the result of device_new_from_parent() in udev_device->parent on first call. device_new_from_parent() sets errno correctly via return_with_errno() when it fails, so a caller gets the right errno on the first invocation. But on any subsequent call for the same object, the cached NULL is returned directly without recomputing anything, so errno reflects whatever happened in between rather than the original failure reason. Cache the errno alongside the parent pointer (new parent_errno field, zero-initialized like the rest of the struct via udev_device_new()'s compound literal) and restore it whenever the cached parent is NULL.
This commit is contained in:
committed by
Yu Watanabe
parent
9d4019b9b7
commit
b2cd050073
@@ -38,6 +38,7 @@ struct udev_device {
|
||||
|
||||
struct udev_device *parent;
|
||||
bool parent_set;
|
||||
int parent_errno;
|
||||
|
||||
struct udev_list *properties;
|
||||
uint64_t properties_generation;
|
||||
@@ -393,9 +394,12 @@ _public_ struct udev_device* udev_device_get_parent(struct udev_device *udev_dev
|
||||
if (!udev_device->parent_set) {
|
||||
udev_device->parent_set = true;
|
||||
udev_device->parent = device_new_from_parent(udev_device);
|
||||
udev_device->parent_errno = udev_device->parent ? 0 : errno;
|
||||
}
|
||||
|
||||
/* TODO: errno will differ here in case parent == NULL */
|
||||
if (!udev_device->parent)
|
||||
errno = udev_device->parent_errno;
|
||||
|
||||
return udev_device->parent;
|
||||
}
|
||||
|
||||
|
||||
Reference in New Issue
Block a user