uart_non_blocking.h

// Copyright 2024 The Pigweed 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
//
//     https://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 <cstdint>
 
#include "pw_bytes/span.h"
#include "pw_function/function.h"
#include "pw_status/status.h"
#include "pw_status/status_with_size.h"
#include "pw_uart/uart_base.h"
 
namespace pw::uart {
 
 
class UartNonBlocking : public UartBase {
 public:
  ~UartNonBlocking() override = default;
 
  Status ReadExactly(
      ByteSpan rx_buffer,
      Function<void(Status status, ConstByteSpan buffer)>&& callback) {
    return DoRead(rx_buffer, rx_buffer.size(), std::move(callback));
  }
 
  Status ReadAtLeast(
      ByteSpan rx_buffer,
      size_t min_bytes,
      Function<void(Status status, ConstByteSpan buffer)>&& callback) {
    return DoRead(rx_buffer, min_bytes, std::move(callback));
  }
 
  bool CancelRead() { return DoCancelRead(); }
 
  Status Write(ConstByteSpan tx_buffer,
               Function<void(StatusWithSize status)>&& callback) {
    return DoWrite(tx_buffer, std::move(callback));
  }
 
  bool CancelWrite() { return DoCancelWrite(); }
 
  Status FlushOutput(Function<void(Status status)>&& callback) {
    return DoFlushOutput(std::move(callback));
  }
 
  bool CancelFlushOutput() { return DoCancelFlushOutput(); }
 
 private:
  virtual Status DoRead(
      ByteSpan rx_buffer,
      size_t min_bytes,
      Function<void(Status status, ConstByteSpan buffer)>&& callback) = 0;
 
  virtual bool DoCancelRead() = 0;
 
  virtual Status DoWrite(ConstByteSpan tx_buffer,
                         Function<void(StatusWithSize status)>&& callback) = 0;
 
  virtual bool DoCancelWrite() = 0;
 
  virtual Status DoFlushOutput(Function<void(Status status)>&& /*callback*/) {
    return Status::Unimplemented();
  }
 
  virtual bool DoCancelFlushOutput() { return false; }
};
 
}  // namespace pw::uart