[VOL-2538] Logging - Implement dynamic log levels in ofagent
Change-Id: I9582230d9d3c34ea84339fddf2b2f3b3d2804808
diff --git a/vendor/go.etcd.io/etcd/raft/log_unstable.go b/vendor/go.etcd.io/etcd/raft/log_unstable.go
new file mode 100644
index 0000000..1bff5a7
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/raft/log_unstable.go
@@ -0,0 +1,157 @@
+// Copyright 2015 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 raft
+
+import pb "go.etcd.io/etcd/raft/raftpb"
+
+// unstable.entries[i] has raft log position i+unstable.offset.
+// Note that unstable.offset may be less than the highest log
+// position in storage; this means that the next write to storage
+// might need to truncate the log before persisting unstable.entries.
+type unstable struct {
+ // the incoming unstable snapshot, if any.
+ snapshot *pb.Snapshot
+ // all entries that have not yet been written to storage.
+ entries []pb.Entry
+ offset uint64
+
+ logger Logger
+}
+
+// maybeFirstIndex returns the index of the first possible entry in entries
+// if it has a snapshot.
+func (u *unstable) maybeFirstIndex() (uint64, bool) {
+ if u.snapshot != nil {
+ return u.snapshot.Metadata.Index + 1, true
+ }
+ return 0, false
+}
+
+// maybeLastIndex returns the last index if it has at least one
+// unstable entry or snapshot.
+func (u *unstable) maybeLastIndex() (uint64, bool) {
+ if l := len(u.entries); l != 0 {
+ return u.offset + uint64(l) - 1, true
+ }
+ if u.snapshot != nil {
+ return u.snapshot.Metadata.Index, true
+ }
+ return 0, false
+}
+
+// maybeTerm returns the term of the entry at index i, if there
+// is any.
+func (u *unstable) maybeTerm(i uint64) (uint64, bool) {
+ if i < u.offset {
+ if u.snapshot != nil && u.snapshot.Metadata.Index == i {
+ return u.snapshot.Metadata.Term, true
+ }
+ return 0, false
+ }
+
+ last, ok := u.maybeLastIndex()
+ if !ok {
+ return 0, false
+ }
+ if i > last {
+ return 0, false
+ }
+
+ return u.entries[i-u.offset].Term, true
+}
+
+func (u *unstable) stableTo(i, t uint64) {
+ gt, ok := u.maybeTerm(i)
+ if !ok {
+ return
+ }
+ // if i < offset, term is matched with the snapshot
+ // only update the unstable entries if term is matched with
+ // an unstable entry.
+ if gt == t && i >= u.offset {
+ u.entries = u.entries[i+1-u.offset:]
+ u.offset = i + 1
+ u.shrinkEntriesArray()
+ }
+}
+
+// shrinkEntriesArray discards the underlying array used by the entries slice
+// if most of it isn't being used. This avoids holding references to a bunch of
+// potentially large entries that aren't needed anymore. Simply clearing the
+// entries wouldn't be safe because clients might still be using them.
+func (u *unstable) shrinkEntriesArray() {
+ // We replace the array if we're using less than half of the space in
+ // it. This number is fairly arbitrary, chosen as an attempt to balance
+ // memory usage vs number of allocations. It could probably be improved
+ // with some focused tuning.
+ const lenMultiple = 2
+ if len(u.entries) == 0 {
+ u.entries = nil
+ } else if len(u.entries)*lenMultiple < cap(u.entries) {
+ newEntries := make([]pb.Entry, len(u.entries))
+ copy(newEntries, u.entries)
+ u.entries = newEntries
+ }
+}
+
+func (u *unstable) stableSnapTo(i uint64) {
+ if u.snapshot != nil && u.snapshot.Metadata.Index == i {
+ u.snapshot = nil
+ }
+}
+
+func (u *unstable) restore(s pb.Snapshot) {
+ u.offset = s.Metadata.Index + 1
+ u.entries = nil
+ u.snapshot = &s
+}
+
+func (u *unstable) truncateAndAppend(ents []pb.Entry) {
+ after := ents[0].Index
+ switch {
+ case after == u.offset+uint64(len(u.entries)):
+ // after is the next index in the u.entries
+ // directly append
+ u.entries = append(u.entries, ents...)
+ case after <= u.offset:
+ u.logger.Infof("replace the unstable entries from index %d", after)
+ // The log is being truncated to before our current offset
+ // portion, so set the offset and replace the entries
+ u.offset = after
+ u.entries = ents
+ default:
+ // truncate to after and copy to u.entries
+ // then append
+ u.logger.Infof("truncate the unstable entries before index %d", after)
+ u.entries = append([]pb.Entry{}, u.slice(u.offset, after)...)
+ u.entries = append(u.entries, ents...)
+ }
+}
+
+func (u *unstable) slice(lo uint64, hi uint64) []pb.Entry {
+ u.mustCheckOutOfBounds(lo, hi)
+ return u.entries[lo-u.offset : hi-u.offset]
+}
+
+// u.offset <= lo <= hi <= u.offset+len(u.entries)
+func (u *unstable) mustCheckOutOfBounds(lo, hi uint64) {
+ if lo > hi {
+ u.logger.Panicf("invalid unstable.slice %d > %d", lo, hi)
+ }
+ upper := u.offset + uint64(len(u.entries))
+ if lo < u.offset || hi > upper {
+ u.logger.Panicf("unstable.slice[%d,%d) out of bound [%d,%d]", lo, hi, u.offset, upper)
+ }
+}