diff options
author | Wim <wim@42.be> | 2018-03-04 23:46:13 +0100 |
---|---|---|
committer | Wim <wim@42.be> | 2018-03-04 23:46:13 +0100 |
commit | 25a72113b122f984c904b24c4af23a1cba1eff45 (patch) | |
tree | f0fb7067d7c958d60ac964afa5b8d5fb79ebc339 /vendor/github.com/pkg/sftp/packet-manager.go | |
parent | 79c4ad5015bd2be47b32141c6d53f0d128bf865b (diff) | |
download | matterbridge-msglm-25a72113b122f984c904b24c4af23a1cba1eff45.tar.gz matterbridge-msglm-25a72113b122f984c904b24c4af23a1cba1eff45.tar.bz2 matterbridge-msglm-25a72113b122f984c904b24c4af23a1cba1eff45.zip |
Add vendor files for spf13/viper
Diffstat (limited to 'vendor/github.com/pkg/sftp/packet-manager.go')
-rw-r--r-- | vendor/github.com/pkg/sftp/packet-manager.go | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/vendor/github.com/pkg/sftp/packet-manager.go b/vendor/github.com/pkg/sftp/packet-manager.go new file mode 100644 index 00000000..bf822e67 --- /dev/null +++ b/vendor/github.com/pkg/sftp/packet-manager.go @@ -0,0 +1,173 @@ +package sftp + +import ( + "encoding" + "sort" + "sync" +) + +// The goal of the packetManager is to keep the outgoing packets in the same +// order as the incoming. This is due to some sftp clients requiring this +// behavior (eg. winscp). + +type packetSender interface { + sendPacket(encoding.BinaryMarshaler) error +} + +type packetManager struct { + requests chan requestPacket + responses chan responsePacket + fini chan struct{} + incoming requestPacketIDs + outgoing responsePackets + sender packetSender // connection object + working *sync.WaitGroup +} + +func newPktMgr(sender packetSender) *packetManager { + s := &packetManager{ + requests: make(chan requestPacket, SftpServerWorkerCount), + responses: make(chan responsePacket, SftpServerWorkerCount), + fini: make(chan struct{}), + incoming: make([]uint32, 0, SftpServerWorkerCount), + outgoing: make([]responsePacket, 0, SftpServerWorkerCount), + sender: sender, + working: &sync.WaitGroup{}, + } + go s.controller() + return s +} + +type responsePackets []responsePacket + +func (r responsePackets) Sort() { + sort.Slice(r, func(i, j int) bool { + return r[i].id() < r[j].id() + }) +} + +type requestPacketIDs []uint32 + +func (r requestPacketIDs) Sort() { + sort.Slice(r, func(i, j int) bool { + return r[i] < r[j] + }) +} + +// register incoming packets to be handled +// send id of 0 for packets without id +func (s *packetManager) incomingPacket(pkt requestPacket) { + s.working.Add(1) + s.requests <- pkt // buffer == SftpServerWorkerCount +} + +// register outgoing packets as being ready +func (s *packetManager) readyPacket(pkt responsePacket) { + s.responses <- pkt + s.working.Done() +} + +// shut down packetManager controller +func (s *packetManager) close() { + // pause until current packets are processed + s.working.Wait() + close(s.fini) +} + +// Passed a worker function, returns a channel for incoming packets. +// The goal is to process packets in the order they are received as is +// requires by section 7 of the RFC, while maximizing throughput of file +// transfers. +func (s *packetManager) workerChan(runWorker func(requestChan)) requestChan { + + rwChan := make(chan requestPacket, SftpServerWorkerCount) + for i := 0; i < SftpServerWorkerCount; i++ { + runWorker(rwChan) + } + + cmdChan := make(chan requestPacket) + runWorker(cmdChan) + + pktChan := make(chan requestPacket, SftpServerWorkerCount) + go func() { + // start with cmdChan + curChan := cmdChan + for pkt := range pktChan { + // on file open packet, switch to rwChan + switch pkt.(type) { + case *sshFxpOpenPacket: + curChan = rwChan + // on file close packet, switch back to cmdChan + // after waiting for any reads/writes to finish + case *sshFxpClosePacket: + // wait for rwChan to finish + s.working.Wait() + // stop using rwChan + curChan = cmdChan + } + s.incomingPacket(pkt) + curChan <- pkt + } + close(rwChan) + close(cmdChan) + s.close() + }() + + return pktChan +} + +// process packets +func (s *packetManager) controller() { + for { + select { + case pkt := <-s.requests: + debug("incoming id: %v", pkt.id()) + s.incoming = append(s.incoming, pkt.id()) + if len(s.incoming) > 1 { + s.incoming.Sort() + } + case pkt := <-s.responses: + debug("outgoing pkt: %v", pkt.id()) + s.outgoing = append(s.outgoing, pkt) + if len(s.outgoing) > 1 { + s.outgoing.Sort() + } + case <-s.fini: + return + } + s.maybeSendPackets() + } +} + +// send as many packets as are ready +func (s *packetManager) maybeSendPackets() { + for { + if len(s.outgoing) == 0 || len(s.incoming) == 0 { + debug("break! -- outgoing: %v; incoming: %v", + len(s.outgoing), len(s.incoming)) + break + } + out := s.outgoing[0] + in := s.incoming[0] + // debug("incoming: %v", s.incoming) + // debug("outgoing: %v", outfilter(s.outgoing)) + if in == out.id() { + s.sender.sendPacket(out) + // pop off heads + copy(s.incoming, s.incoming[1:]) // shift left + s.incoming = s.incoming[:len(s.incoming)-1] // remove last + copy(s.outgoing, s.outgoing[1:]) // shift left + s.outgoing = s.outgoing[:len(s.outgoing)-1] // remove last + } else { + break + } + } +} + +//func outfilter(o []responsePacket) []uint32 { +// res := make([]uint32, 0, len(o)) +// for _, v := range o { +// res = append(res, v.id()) +// } +// return res +//} |