All Hashring public functions use the mutex if needed (9b9adb9b) · Commits · The Tor Project / Anti-censorship / rdsys

pkg/core/hashring.go

+19 −0

Original line number	Diff line number	Diff line
		@@ -88,16 +88,19 @@ func (m *ResourceDiff) String() string {
		}

		// Len implements the sort interface.
		// This function is unsafe and needs a mutex lock before being used
		func (h *Hashring) Len() int {
		return len(h.hashnodes)
		}

		// Less implements the sort interface.
		// This function is unsafe and needs a mutex lock before being used
		func (h *Hashring) Less(i, j int) bool {
		return h.hashnodes[i].hashkey < h.hashnodes[j].hashkey
		}

		// Swap implements the sort interface.
		// This function is unsafe and needs a mutex lock before being used
		func (h *Hashring) Swap(i, j int) {
		h.hashnodes[i], h.hashnodes[j] = h.hashnodes[j], h.hashnodes[i]
		}
		@@ -203,7 +206,11 @@ func (h *Hashring) AddOrUpdate(r Resource) (event int) {
		func (h *Hashring) Remove(r Resource) error {
		h.Lock()
		defer h.Unlock()
		return h.remove(r)
		}

		// remove without locking the mutex
		func (h *Hashring) remove(r Resource) error {
		i, err := h.getIndex(r.Uid())
		if err != nil {
		return err
		@@ -247,6 +254,8 @@ func (h *Hashring) getIndex(k Hashkey) (int, error) {
		// the given hash key, we return the element whose hash key is the closest to
		// the given hash key in descending direction.
		func (h *Hashring) Get(k Hashkey) (Resource, error) {
		h.RLock()
		defer h.RUnlock()

		i, err := h.getIndex(k)
		if err != nil && i == -1 {
		@@ -258,6 +267,8 @@ func (h *Hashring) Get(k Hashkey) (Resource, error) {
		// GetExact attempts to retrieve the element identified by the given hash key.
		// If we cannot find the element, an error is returned.
		func (h *Hashring) GetExact(k Hashkey) (Resource, error) {
		h.RLock()
		defer h.RUnlock()

		i, err := h.getIndex(k)
		if err != nil {
		@@ -270,6 +281,8 @@ func (h *Hashring) GetExact(k Hashkey) (Resource, error) {
		// given number of elements. If the number of desired elements exceeds the
		// number of elements in the hashring, an error is returned.
		func (h *Hashring) GetMany(k Hashkey, num int) ([]Resource, error) {
		h.RLock()
		defer h.RUnlock()

		if num > h.Len() {
		return nil, errors.New("requested more elements than hashring has")
		@@ -295,6 +308,8 @@ func (h *Hashring) GetMany(k Hashkey, num int) ([]Resource, error) {

		// GetAll returns all of the hashring's resources.
		func (h *Hashring) GetAll() []Resource {
		h.RLock()
		defer h.RUnlock()

		var elems []Resource
		for _, node := range h.hashnodes {
		@@ -306,6 +321,8 @@ func (h *Hashring) GetAll() []Resource {
		// Filter filters the resources of this hashring with the given filter function
		// and returns the remaining resources as another hashring.
		func (h Hashring) Filter(f FilterFunc) Hashring {
		h.RLock()
		defer h.RUnlock()

		r := &Hashring{}
		for _, n := range h.hashnodes {
		@@ -318,6 +335,8 @@ func (h Hashring) Filter(f FilterFunc) Hashring {

		// Prune prunes and returns expired resources from the hashring.
		func (h *Hashring) Prune() []Resource {
		h.Lock()
		defer h.Unlock()

		now := time.Now().UTC()
		pruned := []Resource{}