printfp.nc

tinyos-2.x.rar

/*
 * "Copyright (c) 2006 Washington University in St. Louis.
 * All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software and its
 * documentation for any purpose, without fee, and without written agreement is
 * hereby granted, provided that the above copyright notice, the following
 * two paragraphs and the author appear in all copies of this software.
 *
 * IN NO EVENT SHALL WASHINGTON UNIVERSITY IN ST. LOUIS BE LIABLE TO ANY PARTY
 * FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING
 * OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF WASHINGTON
 * UNIVERSITY IN ST. LOUIS HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * WASHINGTON UNIVERSITY IN ST. LOUIS SPECIFICALLY DISCLAIMS ANY WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
 * ON AN "AS IS" BASIS, AND WASHINGTON UNIVERSITY IN ST. LOUIS HAS NO
 * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR
 * MODIFICATIONS."
 */

/**
 * This is the PrintfP component.  It provides the printf service for printing
 * data over the serial interface using the standard c-style printf command.  
 * It must be started via the SplitControl interface it provides.  Data
 * printed using printf are buffered and only sent over the serial line after
 * making a call to PrintfFlush.flush().  This buffer has a maximum size of 
 * 250 bytes at present.  After calling start on this component, printf
 * statements can be made anywhere throughout your code, so long as you include
 * the "printf.h" header file in every file you wish to use it.  Standard
 * practice is to start the printf service in the main application, and set up 
 * a timer to periodically flush the printf buffer (500ms should do).  In future
 * versions, user defined buffer sizes as well as well as automatic flushing at 
 * user defined intervals will be supported.  
 *
 * The printf service is currently only available for msp430 based motes 
 * (i.e. telos, eyes) and atmega128 based motes (i.e. mica2, micaz).  On the
 * atmega platforms, avr-libc version 1.4 or above mus tbe used.
 * 
 *
 * @author Kevin Klues ([e-mail])
 * @version $Revision: 1.1 $
 * @date $Date: 2008/06/12 12:33:47 $
 */

#include "printf.h"

#ifdef _H_atmega128hardware_H
static int uart_putchar(char c, FILE *stream);
static FILE atm128_stdout = FDEV_SETUP_STREAM(uart_putchar, NULL, _FDEV_SETUP_WRITE);
#endif

module PrintfP {
  provides {
    interface SplitControl as PrintfControl;
    interface PrintfFlush;
  }
  uses {
    interface SplitControl as SerialControl;
    interface AMSend;
    interface Packet;
  }
}
implementation {
  
  enum {
    S_STARTED,
    S_STOPPED,
    S_FLUSHING,
  };

  message_t printfMsg;
  nx_uint8_t buffer[PRINTF_BUFFER_SIZE];
  norace nx_uint8_t* next_byte;
  uint8_t state = S_STOPPED;
  uint32_t bytes_left_to_flush;
  uint8_t length_to_send;
  
  task void retrySend() {
    if(call AMSend.send(AM_BROADCAST_ADDR, &printfMsg, sizeof(printf_msg_t)) != SUCCESS)
      post retrySend();
  }
  
  void sendNext() {
    printf_msg_t* m = (printf_msg_t*)call Packet.getPayload(&printfMsg, sizeof(printf_msg_t));
    length_to_send = (bytes_left_to_flush < sizeof(printf_msg_t)) ? bytes_left_to_flush : sizeof(printf_msg_t);
    memset(m->buffer, 0, sizeof(printf_msg_t));
    memcpy(m->buffer, (nx_uint8_t*)next_byte, length_to_send);
    if(call AMSend.send(AM_BROADCAST_ADDR, &printfMsg, sizeof(printf_msg_t)) != SUCCESS)
      post retrySend();  
    else {
      bytes_left_to_flush -= length_to_send;
      next_byte += length_to_send;
    }
  }

  command error_t PrintfControl.start() {
    if(state == S_STOPPED)
      return call SerialControl.start();
    return FAIL;
  }
  
  command error_t PrintfControl.stop() {
    if(state == S_STARTED)
      return call SerialControl.stop();
    return FAIL;
  }

  event void SerialControl.startDone(error_t error) {
    if(error != SUCCESS) {
      signal PrintfControl.startDone(error);
      return;
    }
#ifdef _H_atmega128hardware_H
    stdout = &atm128_stdout;
#endif
    atomic {
      memset(buffer, 0, sizeof(buffer));
      next_byte = buffer;
      bytes_left_to_flush = 0; 
      length_to_send = 0;
      state = S_STARTED;
    }
    signal PrintfControl.startDone(error); 
  }

  event void SerialControl.stopDone(error_t error) {
    if(error != SUCCESS) {
      signal PrintfControl.stopDone(error);
      return;
    }
    atomic state = S_STOPPED;
    signal PrintfControl.stopDone(error); 
  }
  
  command error_t PrintfFlush.flush() {
    atomic {
      if(state == S_STARTED && (next_byte > buffer)) {
        state = S_FLUSHING;
        bytes_left_to_flush = next_byte - buffer;
        next_byte = buffer;
      }
      else return FAIL;
    }
    sendNext();
    return SUCCESS;
  }
    
  event void AMSend.sendDone(message_t* msg, error_t error) {    
    if(error == SUCCESS) {
      if(bytes_left_to_flush > 0)
        sendNext();
      else {
        next_byte = buffer;
        bytes_left_to_flush = 0; 
        length_to_send = 0;
        atomic state = S_STARTED;
      signal PrintfFlush.flushDone(error);
    }
  }
  else post retrySend();
  }
  
#ifdef _H_msp430hardware_h
  int putchar(int c) __attribute__((noinline)) @C() @spontaneous() {
#endif
#ifdef _H_atmega128hardware_H
  int uart_putchar(char c, FILE *stream) __attribute__((noinline)) @C() @spontaneous() {
#endif
    atomic {
      if(state == S_STARTED && ((next_byte-buffer) < PRINTF_BUFFER_SIZE)) {
        *(next_byte++) = c;
        return 0;
      }
      else return -1;
    }
  }
}