1 /* 2 * Copyright (c) 2021 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 #ifndef NET_DCSCTP_SOCKET_CONTEXT_H_ 11 #define NET_DCSCTP_SOCKET_CONTEXT_H_ 12 13 #include <cstdint> 14 15 #include "absl/strings/string_view.h" 16 #include "net/dcsctp/common/internal_types.h" 17 #include "net/dcsctp/packet/sctp_packet.h" 18 #include "net/dcsctp/public/dcsctp_socket.h" 19 #include "net/dcsctp/public/types.h" 20 21 namespace dcsctp { 22 23 // A set of helper methods used by handlers to e.g. send packets. 24 // 25 // Implemented by the TransmissionControlBlock. 26 class Context { 27 public: 28 virtual ~Context() = default; 29 30 // Indicates if a connection has been established. 31 virtual bool is_connection_established() const = 0; 32 33 // Returns this side's initial TSN value. 34 virtual TSN my_initial_tsn() const = 0; 35 36 // Returns the peer's initial TSN value. 37 virtual TSN peer_initial_tsn() const = 0; 38 39 // Returns the socket callbacks. 40 virtual DcSctpSocketCallbacks& callbacks() const = 0; 41 42 // Observes a measured RTT value, in milliseconds. 43 virtual void ObserveRTT(DurationMs rtt_ms) = 0; 44 45 // Returns the current Retransmission Timeout (rto) value, in milliseconds. 46 virtual DurationMs current_rto() const = 0; 47 48 // Increments the transmission error counter, given a human readable reason. 49 virtual bool IncrementTxErrorCounter(absl::string_view reason) = 0; 50 51 // Clears the transmission error counter. 52 virtual void ClearTxErrorCounter() = 0; 53 54 // Returns true if there have been too many retransmission errors. 55 virtual bool HasTooManyTxErrors() const = 0; 56 57 // Returns a PacketBuilder, filled in with the correct verification tag. 58 virtual SctpPacket::Builder PacketBuilder() const = 0; 59 60 // Builds the packet from `builder` and sends it. 61 virtual void Send(SctpPacket::Builder& builder) = 0; 62 }; 63 64 } // namespace dcsctp 65 66 #endif // NET_DCSCTP_SOCKET_CONTEXT_H_ 67