net/datagram_socket.h

/*
Copyright 2022 The Photon Authors

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

#pragma once

#include <photon/common/message.h>
#include <photon/net/socket.h>

namespace photon {
namespace net {

class IDatagramSocket : public IMessage,
                        public ISocketBase,
                        public ISocketName {
protected:
    virtual int connect(const Addr* addr, size_t addr_len) = 0;
    virtual int bind(const Addr* addr, size_t addr_len) = 0;

    IMessage* cast() { return (IMessage*)this; }

    template <typename B, typename S>
    ssize_t sendto(B* buf, S count, const Addr* to_addr, size_t addr_len,
                   int flags = 0) {
        return cast()->send(buf, count, to_addr, addr_len, flags);
    }
    template <typename B, typename S>
    ssize_t recvfrom(B* buf, S count, Addr* from_addr, size_t* addr_len,
                     int flags = 0) {
        return cast()->recv(buf, count, from_addr, addr_len, flags);
    }

    template <typename B, typename S>
    ssize_t send(B* buf, S count, int flags = 0) {
        return cast()->send(buf, count, nullptr, 0, flags);
    }
    template <typename B, typename S>
    ssize_t recv(B* buf, S count, int flags = 0) {
        return cast()->recv(buf, count, nullptr, nullptr, flags);
    }
    using IMessage::recv;
    using IMessage::send;

    virtual uint64_t timeout() const = 0;
    virtual void timeout(uint64_t) = 0;
};

class UDPSocket : public IDatagramSocket {
protected:
    using base = IDatagramSocket;
    using base::bind;
    using base::connect;

public:
    using base::recv;
    using base::send;
    int connect(const EndPoint& ep)   { return connect((Addr*)&ep, sizeof(ep)); }
    int bind(const EndPoint& ep)      { return bind((Addr*)&ep, sizeof(ep)); }
    int bind(uint16_t port = 0)       { return bind_v4any(0); }
    int bind(uint16_t port, IPAddr a) { return bind(EndPoint(a, port)); }
    int bind_v4any(uint16_t port = 0) { return bind(EndPoint(IPAddr::V4Any(), port)); }
    int bind_v6any(uint16_t port = 0) { return bind(EndPoint(IPAddr::V6Any(), port)); }
    int bind_v4localhost(uint16_t port = 0) { return bind(EndPoint(IPAddr::V4Loopback(), port)); }
    int bind_v6localhost(uint16_t port = 0) { return bind(EndPoint(IPAddr::V6Loopback(), port)); }

    template <typename B, typename S>
    ssize_t sendto(B* buf, S count, const EndPoint& ep, int flags = 0) {
        return base::sendto(buf, count, (Addr*)&ep, sizeof(ep), flags);
    }
    template <typename B, typename S>
    ssize_t recvfrom(B* buf, S count, EndPoint* from, int flags = 0) {
        size_t addr_len = sizeof(*from);
        return base::recvfrom(buf, count, (Addr*)from, &addr_len, flags);
    }
};

class UDS_DatagramSocket : public IDatagramSocket {
protected:
    using base = IDatagramSocket;
    using base::bind;
    using base::connect;

public:
    using base::recv;
    using base::send;
    int connect(const char* path) { return connect((Addr*)path, 0); }
    int bind(const char* path) { return bind((Addr*)path, 0); }
    template <typename B, typename S>
    ssize_t sendto(B* buf, S count, const char* path, int flags = 0) {
        return base::sendto(buf, count, (Addr*)path, 0, flags);
    }
    // Unix Domain Socket can not detect recvfrom address
    // just ignore it, and forward to `recv` method
    template <typename B, typename S>
    ssize_t recvfrom(B* buf, S count, char* from, size_t len, int flags = 0) {
        return base::recv(buf, count, flags);
    }
};

UDPSocket* new_udp_socket(int fd = -1);

UDS_DatagramSocket* new_uds_datagram_socket(int fd = -1);

}  // namespace net
}  // namespace photon