params.cpp

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//--------------------------------------------------------------------
//   params.cpp
//   ----------    
//   A simple processor of parameter files
//   Implemented: TParams
//
//   Moving point workload generator v 1.1 
//   Copyright(c) 1999-2001, Aalborg University
//

#include "params.h"
#include <iostream.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>

#define isnamechar(a) (isalnum(a) || (a) == '_')

//------------------------------------------------
TParams::TParams (const char* fname) : 
         error(false), silent(false)
{
   FILE* pf;
   int   len;

   if ((pf = fopen (fname, "rt")) == NULL)
   {
      cout << endl <<
      "GENERATOR Error: Unable to open the parameters file " << fname << endl;
      exit (1);
   }
   fseek (pf, 0L, SEEK_END);
   len = (int) ftell (pf);
   rewind (pf);
   buffer = new char[len+1];
   fread (buffer, len, 1, pf);
   buffer[len] = '\x0';
   fclose (pf);
}

//------------------------------------------------
TParams::~TParams()
{
   delete buffer;
}

//------------------------------------------------
//   strname -  Function for locating the name in the string,
//              name being defind the same way as identifier is defined
//              in most programming languages
//

static char* strname (char* buffer, const char* name)
{
   char* p   = buffer;
   int   len = strlen (name);

   do
   {
      p = strstr (++p, name);
   } while (p && (p[-1] != '\n' || isnamechar(p[len])));

   return p;
}

//------------------------------------------------
//   getRaw - returned string is internal buffer and
//            is valid only until the subsequent call to getRaw.
//            If end != NULL then pointer to the ending semicolon of
//            parameter is returned in end.
//            Returns NULL if parameter cannot be found.
//

char* TParams::getRaw (const char* pname, char** end)
{
   static char ret[50];
   int   l;
   char* e;
   char* p = strname (buffer, pname);
   
   if (p) p = strchr(p, ':');
   if (!p)
   {
      if (!silent) 
         cout << endl << "GENERATOR Warning: Cannot find the parameter " 
              << pname << endl;
      return NULL;
   }
   e = strchr (++p, ';');
   if (!e) e = strchr(p, '\n');
   l = e - p < 50 ? e - p : 49;
   memcpy (ret, p, l);
   ret[l] = '\x0';
   if (end) *end = e;
   return ret;
}

//------------------------------------------------
long TParams::getInt (const char* pname)
{
   char* tmp = getRaw (pname);
   
   error = !tmp; 
   return tmp ? atol (tmp) : 0;
}

//------------------------------------------------
double TParams::getFloat (const char* pname)
{
   char* tmp = getRaw (pname);

   error = !tmp; 
   return tmp ? atof (tmp) : 0;
}

//------------------------------------------------
char* TParams::getString (const char* pname)
{
   char* tmp = getRaw (pname);
   
   error = !tmp;
   return tmp; 
}