66 lines
1.8 KiB
Go
66 lines
1.8 KiB
Go
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package chanacceptor
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import (
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"sync"
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"sync/atomic"
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)
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// ChainedAcceptor represents a conjunction of ChannelAcceptor results.
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type ChainedAcceptor struct {
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// acceptors is a map of ChannelAcceptors that will be evaluated when
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// the ChainedAcceptor's Accept method is called.
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acceptors map[uint64]ChannelAcceptor
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acceptorsMtx sync.RWMutex
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acceptorID uint64 // To be used atomically.
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}
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// NewChainedAcceptor initializes a ChainedAcceptor.
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func NewChainedAcceptor() *ChainedAcceptor {
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return &ChainedAcceptor{
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acceptors: make(map[uint64]ChannelAcceptor),
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}
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}
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// AddAcceptor adds a ChannelAcceptor to this ChainedAcceptor.
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func (c *ChainedAcceptor) AddAcceptor(acceptor ChannelAcceptor) uint64 {
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id := atomic.AddUint64(&c.acceptorID, 1)
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c.acceptorsMtx.Lock()
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c.acceptors[id] = acceptor
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c.acceptorsMtx.Unlock()
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// Return the id so that a caller can call RemoveAcceptor.
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return id
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}
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// RemoveAcceptor removes a ChannelAcceptor from this ChainedAcceptor given
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// an ID.
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func (c *ChainedAcceptor) RemoveAcceptor(id uint64) {
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c.acceptorsMtx.Lock()
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delete(c.acceptors, id)
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c.acceptorsMtx.Unlock()
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}
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// Accept evaluates the results of all ChannelAcceptors in the acceptors map
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// and returns the conjunction of all these predicates.
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//
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// NOTE: Part of the ChannelAcceptor interface.
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func (c *ChainedAcceptor) Accept(req *ChannelAcceptRequest) bool {
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result := true
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c.acceptorsMtx.RLock()
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for _, acceptor := range c.acceptors {
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// We call Accept first in case any acceptor (perhaps an RPCAcceptor)
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// wishes to be notified about ChannelAcceptRequest.
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result = acceptor.Accept(req) && result
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}
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c.acceptorsMtx.RUnlock()
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return result
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}
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// A compile-time constraint to ensure ChainedAcceptor implements the
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// ChannelAcceptor interface.
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var _ ChannelAcceptor = (*ChainedAcceptor)(nil)
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