parser.cpp

linux下的CAN BUS驱动代码。适合在arm平台使用。

//****************************************************************************
// Copyright (C) 2001-2006  PEAK System-Technik GmbH
//
// [e-mail] 
// www.peak-system.com
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
//
// Maintainer(s): Klaus Hitschler ([e-mail])
//****************************************************************************

//****************************************************************************
//
// parser.cpp - parses the input file and put the messages into a list
//
// $Id: parser.cpp 517 2007-07-09 09:40:42Z edouard $
//
//****************************************************************************

//****************************************************************************
// INCLUDES
#include <cstdio>
#include <cstdlib>
#include <cerrno>
#include <string>

#include <iostream>
#include <fstream>

#include <ctype.h>
#include <libpcan.h>
#include <src/parser.h>

//****************************************************************************
// DEFINES

//****************************************************************************
// GLOBALS

//****************************************************************************
// LOCALS

//****************************************************************************
// CODE 

//----------------------------------------------------------------------------
// construct and destruct
parser::parser(void)
{
  m_szFileName = NULL;
  m_nLastError = 0;
}

parser::parser(const char *filename)
{
  m_szFileName = filename;
  m_nLastError = 0;
}

parser::~parser(void)
{
}

//----------------------------------------------------------------------------
// skip blanks and tabs
void parser::skip_blanks(char **ptr)
{
  // remove blanks or tabs
  while ((**ptr == ' ') || (**ptr == '\t')) 
    (*ptr)++; 
}

//----------------------------------------------------------------------------
// skip blanks, return 0 if the 1st non-blank char is not '\n'
int parser::skip_blanks_and_test_for_CR(char **ptr)
{
  // remove blanks or tabs
  skip_blanks(ptr);
  
  if (**ptr == '\n')
    return -1;
  else
    return 0;
}

//----------------------------------------------------------------------------
// extract a number, either hex or decimal from a string
int parser::scan_unsigned_number(char **ptr, __u32 *dwResult)
{
  char *p = *ptr;
  
  *dwResult = strtoul(p, ptr, 0); 
  
  if (p != *ptr)
    return 0;
    
  return ERANGE;
}

//----------------------------------------------------------------------------
// extract a char from a string
char parser::scan_char(char **ptr)
{
  return *(*ptr)++;
}
  
//----------------------------------------------------------------------------
// parses a message command
int parser::parse_input_message(char *buffer, TPCANMsg *Message)
{
  char *ptr = buffer;
  __u32 dwLen;
  __u32 dwDat;
  uint i;
  int err = EINVAL;
  
  // remove leading blanks
  skip_blanks(&ptr);
  
  // search for 'm' or 'r' to distinguish between message or remote transmit requests
  Message->MSGTYPE  = 0; 
  switch (scan_char(&ptr))
  {
    case 'm':  break; // normal message
    case 'r':  Message->MSGTYPE |= MSGTYPE_RTR; break; // rtr message

    default:   goto reject;
  }
  if (skip_blanks_and_test_for_CR(&ptr)) // no CR allowed here
    goto reject;
   
  // read message type
  switch (scan_char(&ptr))
  {
    case 's': break;
    case 'e': Message->MSGTYPE |= MSGTYPE_EXTENDED; break;
    
    default:  goto reject;
  }
  if (skip_blanks_and_test_for_CR(&ptr))
    goto reject;
  
  // read CAN-ID
  if ((err = scan_unsigned_number(&ptr, &Message->ID)))
    goto reject;
  if (Message->MSGTYPE & MSGTYPE_EXTENDED)
  {
    if (Message->ID > 0x3fffffff)
      goto reject;
  }
  else
  {
    if (Message->ID > 2047)
      goto reject;
  }
  if (skip_blanks_and_test_for_CR(&ptr))
    goto reject;
  
  //read datalength
  if ((err = scan_unsigned_number(&ptr, &dwLen)))
    goto reject;
  if (dwLen > 8)
    goto reject;  
  Message->LEN = (__u8)dwLen;  
    
  // read data elements up to message len
  i = 0;
  while (i < dwLen)
  {
    if (skip_blanks_and_test_for_CR(&ptr))
    goto reject;
    
    if ((err = scan_unsigned_number(&ptr, &dwDat)))
      goto reject;
    if (dwDat > 255)
      goto reject;    
	  Message->DATA[i] = (__u8)dwDat;
    	  
	  i++; 
  }   
  return 0; 
  
  reject:
  return err;
}

//----------------------------------------------------------------------------
// returns the last error
int parser::nGetLastError(void)
{
  int error = m_nLastError;
  
  m_nLastError = 0;
  return error;
}

//----------------------------------------------------------------------------
// set the filename
void parser::setFileName(const char *filename)
{
  m_szFileName = filename;
}
  
//----------------------------------------------------------------------------
// returns the list of messages
std::list<TPCANMsg> *parser::Messages(void)
{
  std::list<TPCANMsg> *_local = &m_List;
  std::string    str;  
  std::ifstream  input(m_szFileName);
  TPCANMsg       Message;
 
  if (!input)
  {
    m_nLastError = errno;
    return NULL;
  }
      
  while (!input.eof() && !input.fail())
  {
    getline(input, str);
    
    if (!parse_input_message(const_cast<char *>(str.c_str()), &Message))
      m_List.push_back(Message);
  }
  
  if (!input.eof() && input.fail())
  {
    m_nLastError = errno;
    _local = NULL;
  }
  
  input.close();  
  
	#if 0 //------------- print out message, begin ----------------
  {
    list<TPCANMsg>::iterator iter;
    int i;
    
    for (iter = m_List.begin(); iter != m_List.end(); iter++)
    {   
      i = 0; 
       
	    printf("%s: 0x%08x 0x%02x %d . ",
	      "transmitest", iter->ID, iter->MSGTYPE, iter->LEN);
	    
	    while (i++ < iter->LEN)
	      printf("0x%02x ", iter->DATA[i]);
	    
		  printf("\n");  
		}
  }
	#endif //------------- print out message, end -----------------    
   
    
  return _local; 
}