message: Add more logging statements
diff: @@ -176,31 +176,36 @@ public:
  template <class LowerLayerPtr>
  ptrdiff_t consume(LowerLayerPtr down, byte_span input, byte_span) {
  + CAF_LOG_TRACE("got" << input.size() << "bytes");
  auto this_layer = this_layer_ptr(down);
  if (input.size() < sizeof(uint32_t)) {
  auto err = make_error(sec::runtime_error,
  "received too few bytes from underlying transport");
  down->abort_reason(std::move(err));
  return -1;
  - } else if (input.size() == sizeof(uint32_t)) {
  + } else if (input.size() == hdr_size) {
  auto u32_size = uint32_t{0};
  memcpy(&u32_size, input.data(), sizeof(uint32_t));
  auto msg_size = static_cast<size_t>(detail::from_network_order(u32_size));
  if (msg_size == 0) {
  // Ignore empty messages.
  + CAF_LOG_DEBUG("received empty message");
  return static_cast<ptrdiff_t>(input.size());
  } else if (msg_size > max_message_length) {
  + CAF_LOG_DEBUG("maximum message size exceeded");
  auto err = make_error(sec::runtime_error,
  "maximum message size exceeded");
  down->abort_reason(std::move(err));
  return -1;
  } else {
  + CAF_LOG_DEBUG("wait for payload of size" << msg_size);
  down->configure_read(receive_policy::exactly(hdr_size + msg_size));
  return 0;
  }
  } else {
  auto [msg_size, msg] = split(input);
  if (msg_size == msg.size() && msg_size + hdr_size == input.size()) {
  + CAF_LOG_DEBUG("got message of size" << msg_size);
  if (upper_layer_.consume(this_layer, msg) >= 0) {
  if (!down->stopped())
  down->configure_read(receive_policy::exactly(hdr_size));
  @@ -209,6 +214,7 @@ public:
  return -1;
  }
  } else {
  + CAF_LOG_DEBUG("received malformed message");
  auto err = make_error(sec::runtime_error, "received malformed message");
  down->abort_reason(std::move(err));
  return -1;
  