echo_server.cpp

#include "rio/buffer.hpp"
#include "rio/io_context.hpp"
#include "rio/net/listener.hpp"
#include "rio/net/protocol.hpp"
#include "rio/net/socket.hpp"
#include "rio/task.hpp"

#include <cstdio>

using namespace rio;
using namespace rio::net;

static Task<void> HandleConnection(IoContext& ctx, Socket<Tcp> conn) {
  Buffer buf;
  while (true) {
    auto n = co_await conn.AsyncRead(buf);
    if (!n) {
      std::printf("[echo] fd=%d closed\n", conn.Fd());
      co_return;
    }
    while (buf.readableBytes() > 0) {
      auto w = co_await conn.AsyncWrite(buf);
      if (!w)
        co_return;
    }
  }
}

static Task<void> AcceptLoop(IoContext& ctx, Listener<Tcp>& listener) {
  while (true) {
    auto result = co_await listener.AsyncAccept();
    if (!result)
      continue;
    std::printf("[echo] accepted fd=%d\n", result->Fd());
    Spawn(ctx, HandleConnection(ctx, std::move(*result)));
  }
}

// echo server: 监听 8080，原样返回收到的数据
// 测试: echo "hello" | nc localhost 8080
int main() {
  auto ctx = std::move(*IoContext::Create());
  auto listener = std::move(
      *Listener<Tcp>::Create(ctx, Endpoint<Tcp>(AddressV4::Any(), 8080)));

  std::printf("[echo] listening on 0.0.0.0:8080\n");
  Spawn(ctx, AcceptLoop(ctx, listener));
  ctx.Run();
}