1 files changed, 179 insertions, 0 deletions
diff --git a/vendor/github.com/pion/sctp/payload_queue.go b/vendor/github.com/pion/sctp/payload_queue.go
new file mode 100644
index 0000000..2d1a35a
--- /dev/null
+++ b/vendor/github.com/pion/sctp/payload_queue.go
@@ -0,0 +1,179 @@
+package sctp
+
+import (
+	"fmt"
+	"sort"
+)
+
+type payloadQueue struct {
+	chunkMap map[uint32]*chunkPayloadData
+	sorted   []uint32
+	dupTSN   []uint32
+	nBytes   int
+}
+
+func newPayloadQueue() *payloadQueue {
+	return &payloadQueue{chunkMap: map[uint32]*chunkPayloadData{}}
+}
+
+func (q *payloadQueue) updateSortedKeys() {
+	if q.sorted != nil {
+		return
+	}
+
+	q.sorted = make([]uint32, len(q.chunkMap))
+	i := 0
+	for k := range q.chunkMap {
+		q.sorted[i] = k
+		i++
+	}
+
+	sort.Slice(q.sorted, func(i, j int) bool {
+		return sna32LT(q.sorted[i], q.sorted[j])
+	})
+}
+
+func (q *payloadQueue) canPush(p *chunkPayloadData, cumulativeTSN uint32) bool {
+	_, ok := q.chunkMap[p.tsn]
+	if ok || sna32LTE(p.tsn, cumulativeTSN) {
+		return false
+	}
+	return true
+}
+
+func (q *payloadQueue) pushNoCheck(p *chunkPayloadData) {
+	q.chunkMap[p.tsn] = p
+	q.nBytes += len(p.userData)
+	q.sorted = nil
+}
+
+// push pushes a payload data. If the payload data is already in our queue or
+// older than our cumulativeTSN marker, it will be recored as duplications,
+// which can later be retrieved using popDuplicates.
+func (q *payloadQueue) push(p *chunkPayloadData, cumulativeTSN uint32) bool {
+	_, ok := q.chunkMap[p.tsn]
+	if ok || sna32LTE(p.tsn, cumulativeTSN) {
+		// Found the packet, log in dups
+		q.dupTSN = append(q.dupTSN, p.tsn)
+		return false
+	}
+
+	q.chunkMap[p.tsn] = p
+	q.nBytes += len(p.userData)
+	q.sorted = nil
+	return true
+}
+
+// pop pops only if the oldest chunk's TSN matches the given TSN.
+func (q *payloadQueue) pop(tsn uint32) (*chunkPayloadData, bool) {
+	q.updateSortedKeys()
+
+	if len(q.chunkMap) > 0 && tsn == q.sorted[0] {
+		q.sorted = q.sorted[1:]
+		if c, ok := q.chunkMap[tsn]; ok {
+			delete(q.chunkMap, tsn)
+			q.nBytes -= len(c.userData)
+			return c, true
+		}
+	}
+
+	return nil, false
+}
+
+// get returns reference to chunkPayloadData with the given TSN value.
+func (q *payloadQueue) get(tsn uint32) (*chunkPayloadData, bool) {
+	c, ok := q.chunkMap[tsn]
+	return c, ok
+}
+
+// popDuplicates returns an array of TSN values that were found duplicate.
+func (q *payloadQueue) popDuplicates() []uint32 {
+	dups := q.dupTSN
+	q.dupTSN = []uint32{}
+	return dups
+}
+
+func (q *payloadQueue) getGapAckBlocks(cumulativeTSN uint32) (gapAckBlocks []gapAckBlock) {
+	var b gapAckBlock
+
+	if len(q.chunkMap) == 0 {
+		return []gapAckBlock{}
+	}
+
+	q.updateSortedKeys()
+
+	for i, tsn := range q.sorted {
+		if i == 0 {
+			b.start = uint16(tsn - cumulativeTSN)
+			b.end = b.start
+			continue
+		}
+		diff := uint16(tsn - cumulativeTSN)
+		if b.end+1 == diff {
+			b.end++
+		} else {
+			gapAckBlocks = append(gapAckBlocks, gapAckBlock{
+				start: b.start,
+				end:   b.end,
+			})
+			b.start = diff
+			b.end = diff
+		}
+	}
+
+	gapAckBlocks = append(gapAckBlocks, gapAckBlock{
+		start: b.start,
+		end:   b.end,
+	})
+
+	return gapAckBlocks
+}
+
+func (q *payloadQueue) getGapAckBlocksString(cumulativeTSN uint32) string {
+	gapAckBlocks := q.getGapAckBlocks(cumulativeTSN)
+	str := fmt.Sprintf("cumTSN=%d", cumulativeTSN)
+	for _, b := range gapAckBlocks {
+		str += fmt.Sprintf(",%d-%d", b.start, b.end)
+	}
+	return str
+}
+
+func (q *payloadQueue) markAsAcked(tsn uint32) int {
+	var nBytesAcked int
+	if c, ok := q.chunkMap[tsn]; ok {
+		c.acked = true
+		c.retransmit = false
+		nBytesAcked = len(c.userData)
+		q.nBytes -= nBytesAcked
+		c.userData = []byte{}
+	}
+
+	return nBytesAcked
+}
+
+func (q *payloadQueue) getLastTSNReceived() (uint32, bool) {
+	q.updateSortedKeys()
+
+	qlen := len(q.sorted)
+	if qlen == 0 {
+		return 0, false
+	}
+	return q.sorted[qlen-1], true
+}
+
+func (q *payloadQueue) markAllToRetrasmit() {
+	for _, c := range q.chunkMap {
+		if c.acked || c.abandoned() {
+			continue
+		}
+		c.retransmit = true
+	}
+}
+
+func (q *payloadQueue) getNumBytes() int {
+	return q.nBytes
+}
+
+func (q *payloadQueue) size() int {
+	return len(q.chunkMap)
+}