[VOL-1386] This commit add "dep" as the package management tool
for voltha-go.
Change-Id: I52bc4911dd00a441756ec7c30f46d45091f3f90e
diff --git a/vendor/github.com/golang-collections/go-datastructures/LICENSE b/vendor/github.com/golang-collections/go-datastructures/LICENSE
new file mode 100644
index 0000000..7a4a3ea
--- /dev/null
+++ b/vendor/github.com/golang-collections/go-datastructures/LICENSE
@@ -0,0 +1,202 @@
+
+ Apache License
+ Version 2.0, January 2004
+ http://www.apache.org/licenses/
+
+ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+ 1. Definitions.
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+ any Contribution intentionally submitted for inclusion in the Work
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+ the terms of any separate license agreement you may have executed
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diff --git a/vendor/github.com/golang-collections/go-datastructures/queue/error.go b/vendor/github.com/golang-collections/go-datastructures/queue/error.go
new file mode 100644
index 0000000..29c062c
--- /dev/null
+++ b/vendor/github.com/golang-collections/go-datastructures/queue/error.go
@@ -0,0 +1,21 @@
+/*
+Copyright 2014 Workiva, LLC
+
+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 queue
+
+import "errors"
+
+var disposedError = errors.New(`Queue has been disposed.`)
diff --git a/vendor/github.com/golang-collections/go-datastructures/queue/priority_queue.go b/vendor/github.com/golang-collections/go-datastructures/queue/priority_queue.go
new file mode 100644
index 0000000..3ccfd57
--- /dev/null
+++ b/vendor/github.com/golang-collections/go-datastructures/queue/priority_queue.go
@@ -0,0 +1,235 @@
+/*
+Copyright 2014 Workiva, LLC
+
+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.
+*/
+
+/*
+The priority queue is almost a spitting image of the logic
+used for a regular queue. In order to keep the logic fast,
+this code is repeated instead of using casts to cast to interface{}
+back and forth. If Go had inheritance and generics, this problem
+would be easier to solve.
+*/
+package queue
+
+import (
+ "sort"
+ "sync"
+)
+
+// Item is an item that can be added to the priority queue.
+type Item interface {
+ // Compare returns a bool that can be used to determine
+ // ordering in the priority queue. Assuming the queue
+ // is in ascending order, this should return > logic.
+ // Return 1 to indicate this object is greater than the
+ // the other logic, 0 to indicate equality, and -1 to indicate
+ // less than other.
+ Compare(other Item) int
+}
+
+type priorityItems []Item
+
+func (items *priorityItems) get(number int) []Item {
+ returnItems := make([]Item, 0, number)
+ index := 0
+ for i := 0; i < number; i++ {
+ if i >= len(*items) {
+ break
+ }
+
+ returnItems = append(returnItems, (*items)[i])
+ (*items)[i] = nil
+ index++
+ }
+
+ *items = (*items)[index:]
+ return returnItems
+}
+
+func (items *priorityItems) insert(item Item) {
+ if len(*items) == 0 {
+ *items = append(*items, item)
+ return
+ }
+
+ equalFound := false
+ i := sort.Search(len(*items), func(i int) bool {
+ result := (*items)[i].Compare(item)
+ if result == 0 {
+ equalFound = true
+ }
+ return result >= 0
+ })
+
+ if equalFound {
+ return
+ }
+
+ if i == len(*items) {
+ *items = append(*items, item)
+ return
+ }
+
+ *items = append(*items, nil)
+ copy((*items)[i+1:], (*items)[i:])
+ (*items)[i] = item
+}
+
+// PriorityQueue is similar to queue except that it takes
+// items that implement the Item interface and adds them
+// to the queue in priority order.
+type PriorityQueue struct {
+ waiters waiters
+ items priorityItems
+ lock sync.Mutex
+ disposeLock sync.Mutex
+ disposed bool
+}
+
+// Put adds items to the queue.
+func (pq *PriorityQueue) Put(items ...Item) error {
+ if len(items) == 0 {
+ return nil
+ }
+
+ pq.lock.Lock()
+ if pq.disposed {
+ pq.lock.Unlock()
+ return disposedError
+ }
+
+ for _, item := range items {
+ pq.items.insert(item)
+ }
+
+ for {
+ sema := pq.waiters.get()
+ if sema == nil {
+ break
+ }
+
+ sema.response.Add(1)
+ sema.wg.Done()
+ sema.response.Wait()
+ if len(pq.items) == 0 {
+ break
+ }
+ }
+
+ pq.lock.Unlock()
+ return nil
+}
+
+// Get retrieves items from the queue. If the queue is empty,
+// this call blocks until the next item is added to the queue. This
+// will attempt to retrieve number of items.
+func (pq *PriorityQueue) Get(number int) ([]Item, error) {
+ if number < 1 {
+ return nil, nil
+ }
+
+ pq.lock.Lock()
+
+ if pq.disposed {
+ pq.lock.Unlock()
+ return nil, disposedError
+ }
+
+ var items []Item
+
+ if len(pq.items) == 0 {
+ sema := newSema()
+ pq.waiters.put(sema)
+ sema.wg.Add(1)
+ pq.lock.Unlock()
+
+ sema.wg.Wait()
+ pq.disposeLock.Lock()
+ if pq.disposed {
+ pq.disposeLock.Unlock()
+ return nil, disposedError
+ }
+ pq.disposeLock.Unlock()
+
+ items = pq.items.get(number)
+ sema.response.Done()
+ return items, nil
+ }
+
+ items = pq.items.get(number)
+ pq.lock.Unlock()
+ return items, nil
+}
+
+// Peek will look at the next item without removing it from the queue.
+func (pq *PriorityQueue) Peek() Item {
+ pq.lock.Lock()
+ defer pq.lock.Unlock()
+ if len(pq.items) > 0 {
+ return pq.items[0]
+ }
+ return nil
+}
+
+// Empty returns a bool indicating if there are any items left
+// in the queue.
+func (pq *PriorityQueue) Empty() bool {
+ pq.lock.Lock()
+ defer pq.lock.Unlock()
+
+ return len(pq.items) == 0
+}
+
+// Len returns a number indicating how many items are in the queue.
+func (pq *PriorityQueue) Len() int {
+ pq.lock.Lock()
+ defer pq.lock.Unlock()
+
+ return len(pq.items)
+}
+
+// Disposed returns a bool indicating if this queue has been disposed.
+func (pq *PriorityQueue) Disposed() bool {
+ pq.lock.Lock()
+ defer pq.lock.Unlock()
+
+ return pq.disposed
+}
+
+// Dispose will prevent any further reads/writes to this queue
+// and frees available resources.
+func (pq *PriorityQueue) Dispose() {
+ pq.lock.Lock()
+ defer pq.lock.Unlock()
+
+ pq.disposeLock.Lock()
+ defer pq.disposeLock.Unlock()
+
+ pq.disposed = true
+ for _, waiter := range pq.waiters {
+ waiter.response.Add(1)
+ waiter.wg.Done()
+ }
+
+ pq.items = nil
+ pq.waiters = nil
+}
+
+// NewPriorityQueue is the constructor for a priority queue.
+func NewPriorityQueue(hint int) *PriorityQueue {
+ return &PriorityQueue{
+ items: make(priorityItems, 0, hint),
+ }
+}
diff --git a/vendor/github.com/golang-collections/go-datastructures/queue/queue.go b/vendor/github.com/golang-collections/go-datastructures/queue/queue.go
new file mode 100644
index 0000000..856ae3e
--- /dev/null
+++ b/vendor/github.com/golang-collections/go-datastructures/queue/queue.go
@@ -0,0 +1,324 @@
+/*
+Copyright 2014 Workiva, LLC
+
+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 queue includes a regular queue and a priority queue.
+These queues rely on waitgroups to pause listening threads
+on empty queues until a message is received. If any thread
+calls Dispose on the queue, any listeners are immediately returned
+with an error. Any subsequent put to the queue will return an error
+as opposed to panicking as with channels. Queues will grow with unbounded
+behavior as opposed to channels which can be buffered but will pause
+while a thread attempts to put to a full channel.
+
+Recently added is a lockless ring buffer using the same basic C design as
+found here:
+
+http://www.1024cores.net/home/lock-free-algorithms/queues/bounded-mpmc-queue
+
+Modified for use with Go with the addition of some dispose semantics providing
+the capability to release blocked threads. This works for both puts
+and gets, either will return an error if they are blocked and the buffer
+is disposed. This could serve as a signal to kill a goroutine. All threadsafety
+is acheived using CAS operations, making this buffer pretty quick.
+
+Benchmarks:
+BenchmarkPriorityQueue-8 2000000 782 ns/op
+BenchmarkQueue-8 2000000 671 ns/op
+BenchmarkChannel-8 1000000 2083 ns/op
+BenchmarkQueuePut-8 20000 84299 ns/op
+BenchmarkQueueGet-8 20000 80753 ns/op
+BenchmarkExecuteInParallel-8 20000 68891 ns/op
+BenchmarkRBLifeCycle-8 10000000 177 ns/op
+BenchmarkRBPut-8 30000000 58.1 ns/op
+BenchmarkRBGet-8 50000000 26.8 ns/op
+
+TODO: We really need a Fibonacci heap for the priority queue.
+TODO: Unify the types of queue to the same interface.
+*/
+package queue
+
+import (
+ "runtime"
+ "sync"
+ "sync/atomic"
+)
+
+type waiters []*sema
+
+func (w *waiters) get() *sema {
+ if len(*w) == 0 {
+ return nil
+ }
+
+ sema := (*w)[0]
+ copy((*w)[0:], (*w)[1:])
+ (*w)[len(*w)-1] = nil // or the zero value of T
+ *w = (*w)[:len(*w)-1]
+ return sema
+}
+
+func (w *waiters) put(sema *sema) {
+ *w = append(*w, sema)
+}
+
+type items []interface{}
+
+func (items *items) get(number int64) []interface{} {
+ returnItems := make([]interface{}, 0, number)
+ index := int64(0)
+ for i := int64(0); i < number; i++ {
+ if i >= int64(len(*items)) {
+ break
+ }
+
+ returnItems = append(returnItems, (*items)[i])
+ (*items)[i] = nil
+ index++
+ }
+
+ *items = (*items)[index:]
+ return returnItems
+}
+
+func (items *items) getUntil(checker func(item interface{}) bool) []interface{} {
+ length := len(*items)
+
+ if len(*items) == 0 {
+ // returning nil here actually wraps that nil in a list
+ // of interfaces... thanks go
+ return []interface{}{}
+ }
+
+ returnItems := make([]interface{}, 0, length)
+ index := 0
+ for i, item := range *items {
+ if !checker(item) {
+ break
+ }
+
+ returnItems = append(returnItems, item)
+ index = i
+ }
+
+ *items = (*items)[index:]
+ return returnItems
+}
+
+type sema struct {
+ wg *sync.WaitGroup
+ response *sync.WaitGroup
+}
+
+func newSema() *sema {
+ return &sema{
+ wg: &sync.WaitGroup{},
+ response: &sync.WaitGroup{},
+ }
+}
+
+// Queue is the struct responsible for tracking the state
+// of the queue.
+type Queue struct {
+ waiters waiters
+ items items
+ lock sync.Mutex
+ disposed bool
+}
+
+// Put will add the specified items to the queue.
+func (q *Queue) Put(items ...interface{}) error {
+ if len(items) == 0 {
+ return nil
+ }
+
+ q.lock.Lock()
+
+ if q.disposed {
+ q.lock.Unlock()
+ return disposedError
+ }
+
+ q.items = append(q.items, items...)
+ for {
+ sema := q.waiters.get()
+ if sema == nil {
+ break
+ }
+ sema.response.Add(1)
+ sema.wg.Done()
+ sema.response.Wait()
+ if len(q.items) == 0 {
+ break
+ }
+ }
+
+ q.lock.Unlock()
+ return nil
+}
+
+// Get will add an item to the queue. If there are some items in the
+// queue, get will return a number UP TO the number passed in as a
+// parameter. If no items are in the queue, this method will pause
+// until items are added to the queue.
+func (q *Queue) Get(number int64) ([]interface{}, error) {
+ if number < 1 {
+ // thanks again go
+ return []interface{}{}, nil
+ }
+
+ q.lock.Lock()
+
+ if q.disposed {
+ q.lock.Unlock()
+ return nil, disposedError
+ }
+
+ var items []interface{}
+
+ if len(q.items) == 0 {
+ sema := newSema()
+ q.waiters.put(sema)
+ sema.wg.Add(1)
+ q.lock.Unlock()
+
+ sema.wg.Wait()
+ // we are now inside the put's lock
+ if q.disposed {
+ return nil, disposedError
+ }
+ items = q.items.get(number)
+ sema.response.Done()
+ return items, nil
+ }
+
+ items = q.items.get(number)
+ q.lock.Unlock()
+ return items, nil
+}
+
+// TakeUntil takes a function and returns a list of items that
+// match the checker until the checker returns false. This does not
+// wait if there are no items in the queue.
+func (q *Queue) TakeUntil(checker func(item interface{}) bool) ([]interface{}, error) {
+ if checker == nil {
+ return nil, nil
+ }
+
+ q.lock.Lock()
+
+ if q.disposed {
+ q.lock.Unlock()
+ return nil, disposedError
+ }
+
+ result := q.items.getUntil(checker)
+ q.lock.Unlock()
+ return result, nil
+}
+
+// Empty returns a bool indicating if this bool is empty.
+func (q *Queue) Empty() bool {
+ q.lock.Lock()
+ defer q.lock.Unlock()
+
+ return len(q.items) == 0
+}
+
+// Len returns the number of items in this queue.
+func (q *Queue) Len() int64 {
+ q.lock.Lock()
+ defer q.lock.Unlock()
+
+ return int64(len(q.items))
+}
+
+// Disposed returns a bool indicating if this queue
+// has had disposed called on it.
+func (q *Queue) Disposed() bool {
+ q.lock.Lock()
+ defer q.lock.Unlock()
+
+ return q.disposed
+}
+
+// Dispose will dispose of this queue. Any subsequent
+// calls to Get or Put will return an error.
+func (q *Queue) Dispose() {
+ q.lock.Lock()
+ defer q.lock.Unlock()
+
+ q.disposed = true
+ for _, waiter := range q.waiters {
+ waiter.response.Add(1)
+ waiter.wg.Done()
+ }
+
+ q.items = nil
+ q.waiters = nil
+}
+
+// New is a constructor for a new threadsafe queue.
+func New(hint int64) *Queue {
+ return &Queue{
+ items: make([]interface{}, 0, hint),
+ }
+}
+
+// ExecuteInParallel will (in parallel) call the provided function
+// with each item in the queue until the queue is exhausted. When the queue
+// is exhausted execution is complete and all goroutines will be killed.
+// This means that the queue will be disposed so cannot be used again.
+func ExecuteInParallel(q *Queue, fn func(interface{})) {
+ if q == nil {
+ return
+ }
+
+ q.lock.Lock() // so no one touches anything in the middle
+ // of this process
+ todo, done := uint64(len(q.items)), int64(-1)
+ // this is important or we might face an infinite loop
+ if todo == 0 {
+ return
+ }
+
+ numCPU := 1
+ if runtime.NumCPU() > 1 {
+ numCPU = runtime.NumCPU() - 1
+ }
+
+ var wg sync.WaitGroup
+ wg.Add(numCPU)
+ items := q.items
+
+ for i := 0; i < numCPU; i++ {
+ go func() {
+ for {
+ index := atomic.AddInt64(&done, 1)
+ if index >= int64(todo) {
+ wg.Done()
+ break
+ }
+
+ fn(items[index])
+ items[index] = 0
+ }
+ }()
+ }
+ wg.Wait()
+ q.lock.Unlock()
+ q.Dispose()
+}
diff --git a/vendor/github.com/golang-collections/go-datastructures/queue/ring.go b/vendor/github.com/golang-collections/go-datastructures/queue/ring.go
new file mode 100644
index 0000000..9c137a9
--- /dev/null
+++ b/vendor/github.com/golang-collections/go-datastructures/queue/ring.go
@@ -0,0 +1,158 @@
+/*
+Copyright 2014 Workiva, LLC
+
+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 queue
+
+import (
+ "runtime"
+ "sync/atomic"
+)
+
+// roundUp takes a uint64 greater than 0 and rounds it up to the next
+// power of 2.
+func roundUp(v uint64) uint64 {
+ v--
+ v |= v >> 1
+ v |= v >> 2
+ v |= v >> 4
+ v |= v >> 8
+ v |= v >> 16
+ v |= v >> 32
+ v++
+ return v
+}
+
+type node struct {
+ position uint64
+ data interface{}
+}
+
+type nodes []*node
+
+// RingBuffer is a MPMC buffer that achieves threadsafety with CAS operations
+// only. A put on full or get on empty call will block until an item
+// is put or retrieved. Calling Dispose on the RingBuffer will unblock
+// any blocked threads with an error. This buffer is similar to the buffer
+// described here: http://www.1024cores.net/home/lock-free-algorithms/queues/bounded-mpmc-queue
+// with some minor additions.
+type RingBuffer struct {
+ nodes nodes
+ queue, dequeue, mask, disposed uint64
+}
+
+func (rb *RingBuffer) init(size uint64) {
+ size = roundUp(size)
+ rb.nodes = make(nodes, size)
+ for i := uint64(0); i < size; i++ {
+ rb.nodes[i] = &node{position: i}
+ }
+ rb.mask = size - 1 // so we don't have to do this with every put/get operation
+}
+
+// Put adds the provided item to the queue. If the queue is full, this
+// call will block until an item is added to the queue or Dispose is called
+// on the queue. An error will be returned if the queue is disposed.
+func (rb *RingBuffer) Put(item interface{}) error {
+ var n *node
+ pos := atomic.LoadUint64(&rb.queue)
+L:
+ for {
+ if atomic.LoadUint64(&rb.disposed) == 1 {
+ return disposedError
+ }
+
+ n = rb.nodes[pos&rb.mask]
+ seq := atomic.LoadUint64(&n.position)
+ switch dif := seq - pos; {
+ case dif == 0:
+ if atomic.CompareAndSwapUint64(&rb.queue, pos, pos+1) {
+ break L
+ }
+ case dif < 0:
+ panic(`Ring buffer in a compromised state during a put operation.`)
+ default:
+ pos = atomic.LoadUint64(&rb.queue)
+ }
+ runtime.Gosched() // free up the cpu before the next iteration
+ }
+
+ n.data = item
+ atomic.StoreUint64(&n.position, pos+1)
+ return nil
+}
+
+// Get will return the next item in the queue. This call will block
+// if the queue is empty. This call will unblock when an item is added
+// to the queue or Dispose is called on the queue. An error will be returned
+// if the queue is disposed.
+func (rb *RingBuffer) Get() (interface{}, error) {
+ var n *node
+ pos := atomic.LoadUint64(&rb.dequeue)
+L:
+ for {
+ if atomic.LoadUint64(&rb.disposed) == 1 {
+ return nil, disposedError
+ }
+
+ n = rb.nodes[pos&rb.mask]
+ seq := atomic.LoadUint64(&n.position)
+ switch dif := seq - (pos + 1); {
+ case dif == 0:
+ if atomic.CompareAndSwapUint64(&rb.dequeue, pos, pos+1) {
+ break L
+ }
+ case dif < 0:
+ panic(`Ring buffer in compromised state during a get operation.`)
+ default:
+ pos = atomic.LoadUint64(&rb.dequeue)
+ }
+ runtime.Gosched() // free up cpu before next iteration
+ }
+ data := n.data
+ n.data = nil
+ atomic.StoreUint64(&n.position, pos+rb.mask+1)
+ return data, nil
+}
+
+// Len returns the number of items in the queue.
+func (rb *RingBuffer) Len() uint64 {
+ return atomic.LoadUint64(&rb.queue) - atomic.LoadUint64(&rb.dequeue)
+}
+
+// Cap returns the capacity of this ring buffer.
+func (rb *RingBuffer) Cap() uint64 {
+ return uint64(len(rb.nodes))
+}
+
+// Dispose will dispose of this queue and free any blocked threads
+// in the Put and/or Get methods. Calling those methods on a disposed
+// queue will return an error.
+func (rb *RingBuffer) Dispose() {
+ atomic.CompareAndSwapUint64(&rb.disposed, 0, 1)
+}
+
+// IsDisposed will return a bool indicating if this queue has been
+// disposed.
+func (rb *RingBuffer) IsDisposed() bool {
+ return atomic.LoadUint64(&rb.disposed) == 1
+}
+
+// NewRingBuffer will allocate, initialize, and return a ring buffer
+// with the specified size.
+func NewRingBuffer(size uint64) *RingBuffer {
+ rb := &RingBuffer{}
+ rb.init(size)
+ return rb
+}