text: ﻿/*
   * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
   * All rights reserved. 
   * 
   * Redistribution and use in source and binary forms, with or without modification, 
   * are permitted provided that the following conditions are met:
   *
   * 1. Redistributions of source code must retain the above copyright notice,
   *    this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright notice,
   *    this list of conditions and the following disclaimer in the documentation
   *    and/or other materials provided with the distribution.
   * 3. The name of the author may not be used to endorse or promote products
   *    derived from this software without specific prior written permission. 
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
   * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
   * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
   * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
   * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
   * OF SUCH DAMAGE.
   *
   * This file is part of the lwIP TCP/IP stack.
   */
  
  /*
   * This is the interface to the platform specific serial IO module
   * It needs to be implemented by those platforms which need SLIP or PPP
   */
  
  #ifndef __SIO_H__
  #define __SIO_H__
  
  #include "lwip/arch.h"
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /* If you want to define sio_fd_t elsewhere or differently,
     define this in your cc.h file. */
  #ifndef __sio_fd_t_defined
  typedef void * sio_fd_t;
  #endif
  
  /* The following functions can be defined to something else in your cc.h file
     or be implemented in your custom sio.c file. */
  
  #ifndef sio_open
  /**
   * Opens a serial device for communication.
   * 
   * @param devnum device number
   * @return handle to serial device if successful, NULL otherwise
   */
  sio_fd_t sio_open(u8_t devnum);
  #endif
  
  #ifndef sio_send
  /**
   * Sends a single character to the serial device.
   * 
   * @param c character to send
   * @param fd serial device handle
   * 
   * @note This function will block until the character can be sent.
   */
  void sio_send(u8_t c, sio_fd_t fd);
  #endif
  
  #ifndef sio_recv
  /**
   * Receives a single character from the serial device.
   * 
   * @param fd serial device handle
   * 
   * @note This function will block until a character is received.
   */
  u8_t sio_recv(sio_fd_t fd);
  #endif
  
  #ifndef sio_read
  /**
   * Reads from the serial device.
   * 
   * @param fd serial device handle
   * @param data pointer to data buffer for receiving
   * @param len maximum length (in bytes) of data to receive
   * @return number of bytes actually received - may be 0 if aborted by sio_read_abort
   * 
   * @note This function will block until data can be received. The blocking
   * can be cancelled by calling sio_read_abort().
   */
  u32_t sio_read(sio_fd_t fd, u8_t *data, u32_t len);
  #endif
  
  #ifndef sio_tryread
  /**
   * Tries to read from the serial device. Same as sio_read but returns
   * immediately if no data is available and never blocks.
   * 
   * @param fd serial device handle
   * @param data pointer to data buffer for receiving
   * @param len maximum length (in bytes) of data to receive
   * @return number of bytes actually received
   */
  u32_t sio_tryread(sio_fd_t fd, u8_t *data, u32_t len);
  #endif
  
  #ifndef sio_write
  /**
   * Writes to the serial device.
   * 
   * @param fd serial device handle
   * @param data pointer to data to send
   * @param len length (in bytes) of data to send
   * @return number of bytes actually sent
   * 
   * @note This function will block until all data can be sent.
   */
  u32_t sio_write(sio_fd_t fd, u8_t *data, u32_t len);
  #endif
  
  #ifndef sio_read_abort
  /**
   * Aborts a blocking sio_read() call.
   * 
   * @param fd serial device handle
   */
  void sio_read_abort(sio_fd_t fd);
  #endif
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* __SIO_H__ */
  