81 lines
1.8 KiB
Go
81 lines
1.8 KiB
Go
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package quic
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import (
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"sync"
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"github.com/lucas-clemente/quic-go/internal/protocol"
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)
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type packetBuffer struct {
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Data []byte
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// refCount counts how many packets Data is used in.
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// It doesn't support concurrent use.
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// It is > 1 when used for coalesced packet.
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refCount int
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}
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// Split increases the refCount.
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// It must be called when a packet buffer is used for more than one packet,
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// e.g. when splitting coalesced packets.
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func (b *packetBuffer) Split() {
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b.refCount++
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}
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// Decrement decrements the reference counter.
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// It doesn't put the buffer back into the pool.
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func (b *packetBuffer) Decrement() {
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b.refCount--
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if b.refCount < 0 {
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panic("negative packetBuffer refCount")
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}
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}
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// MaybeRelease puts the packet buffer back into the pool,
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// if the reference counter already reached 0.
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func (b *packetBuffer) MaybeRelease() {
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// only put the packetBuffer back if it's not used any more
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if b.refCount == 0 {
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b.putBack()
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}
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}
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// Release puts back the packet buffer into the pool.
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// It should be called when processing is definitely finished.
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func (b *packetBuffer) Release() {
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b.Decrement()
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if b.refCount != 0 {
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panic("packetBuffer refCount not zero")
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}
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b.putBack()
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}
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// Len returns the length of Data
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func (b *packetBuffer) Len() protocol.ByteCount {
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return protocol.ByteCount(len(b.Data))
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}
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func (b *packetBuffer) putBack() {
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if cap(b.Data) != int(protocol.MaxPacketBufferSize) {
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panic("putPacketBuffer called with packet of wrong size!")
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}
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bufferPool.Put(b)
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}
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var bufferPool sync.Pool
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func getPacketBuffer() *packetBuffer {
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buf := bufferPool.Get().(*packetBuffer)
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buf.refCount = 1
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buf.Data = buf.Data[:0]
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return buf
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}
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func init() {
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bufferPool.New = func() interface{} {
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return &packetBuffer{
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Data: make([]byte, 0, protocol.MaxPacketBufferSize),
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}
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}
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}
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