[VOL-2312] Logging - Integrate voltctl with new etcd-based dynamic loglevel mechanism. Testing is in progress
Change-Id: I2e13bb79008c9a49ebb6f58e575f51efebe6dbfd
diff --git a/vendor/go.etcd.io/etcd/raft/tracker/inflights.go b/vendor/go.etcd.io/etcd/raft/tracker/inflights.go
new file mode 100644
index 0000000..1a05634
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/raft/tracker/inflights.go
@@ -0,0 +1,132 @@
+// Copyright 2019 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package tracker
+
+// Inflights limits the number of MsgApp (represented by the largest index
+// contained within) sent to followers but not yet acknowledged by them. Callers
+// use Full() to check whether more messages can be sent, call Add() whenever
+// they are sending a new append, and release "quota" via FreeLE() whenever an
+// ack is received.
+type Inflights struct {
+ // the starting index in the buffer
+ start int
+ // number of inflights in the buffer
+ count int
+
+ // the size of the buffer
+ size int
+
+ // buffer contains the index of the last entry
+ // inside one message.
+ buffer []uint64
+}
+
+// NewInflights sets up an Inflights that allows up to 'size' inflight messages.
+func NewInflights(size int) *Inflights {
+ return &Inflights{
+ size: size,
+ }
+}
+
+// Clone returns an *Inflights that is identical to but shares no memory with
+// the receiver.
+func (in *Inflights) Clone() *Inflights {
+ ins := *in
+ ins.buffer = append([]uint64(nil), in.buffer...)
+ return &ins
+}
+
+// Add notifies the Inflights that a new message with the given index is being
+// dispatched. Full() must be called prior to Add() to verify that there is room
+// for one more message, and consecutive calls to add Add() must provide a
+// monotonic sequence of indexes.
+func (in *Inflights) Add(inflight uint64) {
+ if in.Full() {
+ panic("cannot add into a Full inflights")
+ }
+ next := in.start + in.count
+ size := in.size
+ if next >= size {
+ next -= size
+ }
+ if next >= len(in.buffer) {
+ in.grow()
+ }
+ in.buffer[next] = inflight
+ in.count++
+}
+
+// grow the inflight buffer by doubling up to inflights.size. We grow on demand
+// instead of preallocating to inflights.size to handle systems which have
+// thousands of Raft groups per process.
+func (in *Inflights) grow() {
+ newSize := len(in.buffer) * 2
+ if newSize == 0 {
+ newSize = 1
+ } else if newSize > in.size {
+ newSize = in.size
+ }
+ newBuffer := make([]uint64, newSize)
+ copy(newBuffer, in.buffer)
+ in.buffer = newBuffer
+}
+
+// FreeLE frees the inflights smaller or equal to the given `to` flight.
+func (in *Inflights) FreeLE(to uint64) {
+ if in.count == 0 || to < in.buffer[in.start] {
+ // out of the left side of the window
+ return
+ }
+
+ idx := in.start
+ var i int
+ for i = 0; i < in.count; i++ {
+ if to < in.buffer[idx] { // found the first large inflight
+ break
+ }
+
+ // increase index and maybe rotate
+ size := in.size
+ if idx++; idx >= size {
+ idx -= size
+ }
+ }
+ // free i inflights and set new start index
+ in.count -= i
+ in.start = idx
+ if in.count == 0 {
+ // inflights is empty, reset the start index so that we don't grow the
+ // buffer unnecessarily.
+ in.start = 0
+ }
+}
+
+// FreeFirstOne releases the first inflight. This is a no-op if nothing is
+// inflight.
+func (in *Inflights) FreeFirstOne() { in.FreeLE(in.buffer[in.start]) }
+
+// Full returns true if no more messages can be sent at the moment.
+func (in *Inflights) Full() bool {
+ return in.count == in.size
+}
+
+// Count returns the number of inflight messages.
+func (in *Inflights) Count() int { return in.count }
+
+// reset frees all inflights.
+func (in *Inflights) reset() {
+ in.count = 0
+ in.start = 0
+}