// Copyright (c) 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef LIBRARIES_NACL_IO_FIFO_CHAR_H_
#define LIBRARIES_NACL_IO_FIFO_CHAR_H_
#include <vector>
#include "nacl_io/fifo_interface.h"
#include "sdk_util/macros.h"
namespace nacl_io {
// FIFOChar
//
// A FIFOChar is a circular buffer, signalling FULL and EMPTY as appropriate.
class FIFOChar : public FIFOInterface {
public:
explicit FIFOChar(size_t size);
virtual ~FIFOChar();
virtual bool IsEmpty();
virtual bool IsFull();
virtual bool Resize(size_t len);
size_t ReadAvailable();
size_t WriteAvailable();
// Reads out no more than the requested len without updating the tail.
// Returns actual amount read.
size_t Peek(void* buf, size_t len);
// Reads out the data making room in the FIFO. Returns actual amount
// read.
size_t Read(void* buf, size_t len);
// Writes into the FIFO no more than len bytes, returns actual amount
// written.
size_t Write(const void* buf, size_t len);
private:
char* buffer_;
size_t size_; // Size of the FIFO
size_t avail_; // How much data is currently available
size_t tail_; // Next read location
DISALLOW_COPY_AND_ASSIGN(FIFOChar);
};
} // namespace nacl_io
#endif // LIBRARIES_NACL_IO_FIFO_CHAR_H_