status-go/vendor/github.com/libp2p/go-libp2p-peerstore/pstoremem/protobook.go

146 lines
2.7 KiB
Go

package pstoremem
import (
"sync"
peer "github.com/libp2p/go-libp2p-core/peer"
pstore "github.com/libp2p/go-libp2p-core/peerstore"
)
type protoSegment struct {
sync.RWMutex
protocols map[peer.ID]map[string]struct{}
}
type protoSegments [256]*protoSegment
func (s *protoSegments) get(p peer.ID) *protoSegment {
return s[byte(p[len(p)-1])]
}
type memoryProtoBook struct {
segments protoSegments
lk sync.RWMutex
interned map[string]string
}
var _ pstore.ProtoBook = (*memoryProtoBook)(nil)
func NewProtoBook() pstore.ProtoBook {
return &memoryProtoBook{
interned: make(map[string]string, 256),
segments: func() (ret protoSegments) {
for i := range ret {
ret[i] = &protoSegment{
protocols: make(map[peer.ID]map[string]struct{}),
}
}
return ret
}(),
}
}
func (pb *memoryProtoBook) internProtocol(proto string) string {
// check if it is interned with the read lock
pb.lk.RLock()
interned, ok := pb.interned[proto]
pb.lk.RUnlock()
if ok {
return interned
}
// intern with the write lock
pb.lk.Lock()
defer pb.lk.Unlock()
// check again in case it got interned in between locks
interned, ok = pb.interned[proto]
if ok {
return interned
}
pb.interned[proto] = proto
return proto
}
func (pb *memoryProtoBook) SetProtocols(p peer.ID, protos ...string) error {
s := pb.segments.get(p)
s.Lock()
defer s.Unlock()
newprotos := make(map[string]struct{}, len(protos))
for _, proto := range protos {
newprotos[pb.internProtocol(proto)] = struct{}{}
}
s.protocols[p] = newprotos
return nil
}
func (pb *memoryProtoBook) AddProtocols(p peer.ID, protos ...string) error {
s := pb.segments.get(p)
s.Lock()
defer s.Unlock()
protomap, ok := s.protocols[p]
if !ok {
protomap = make(map[string]struct{})
s.protocols[p] = protomap
}
for _, proto := range protos {
protomap[pb.internProtocol(proto)] = struct{}{}
}
return nil
}
func (pb *memoryProtoBook) GetProtocols(p peer.ID) ([]string, error) {
s := pb.segments.get(p)
s.RLock()
defer s.RUnlock()
out := make([]string, 0, len(s.protocols))
for k := range s.protocols[p] {
out = append(out, k)
}
return out, nil
}
func (pb *memoryProtoBook) RemoveProtocols(p peer.ID, protos ...string) error {
s := pb.segments.get(p)
s.Lock()
defer s.Unlock()
protomap, ok := s.protocols[p]
if !ok {
// nothing to remove.
return nil
}
for _, proto := range protos {
delete(protomap, pb.internProtocol(proto))
}
return nil
}
func (pb *memoryProtoBook) SupportsProtocols(p peer.ID, protos ...string) ([]string, error) {
s := pb.segments.get(p)
s.RLock()
defer s.RUnlock()
out := make([]string, 0, len(protos))
for _, proto := range protos {
if _, ok := s.protocols[p][proto]; ok {
out = append(out, proto)
}
}
return out, nil
}