Message-Id: <200212310422.gBV4MijQ025653@chac.its.uow.edu.au>
Date: Tue, 31 Dec 2002 15:26:51 +1000
From: Y Chen <yc12 AT uow DOT edu DOT au>
To: "djgpp AT delorie DOT com" <djgpp AT delorie DOT com>
Subject: open() in c++
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Reply-To: djgpp AT delorie DOT com

Dear Sir,

I don't know why djgpp cannot compile the following sentences(the files are at the bottom):

  char cFilename[101];
  pFile->open(cFilename, aiMode);

I used:
	gxx -c IOBase.cpp

It gives the following errors:

IOBase.cpp: In member function `char TIOBase::OpenFile(char*, int)':
IOBase.cpp:45: no matching function for call to `std::basic_fstream<char,
   std::char_traits<char> >::open(char[101], int&)'
d:/djgpp/lang/cxx-v3/bits/std_fstream.h:409: candidates are: void
   std::basic_fstream<_CharT, _Traits>::open(const char*, std::_Ios_Openmode =
   (std::ios_base::in | std::ios_base::out)) [with _CharT = char, _Traits =
   std::char_traits<char>]
IOBase.cpp: In member function `char TIOBase::OpenFile(std::fstream*, char*,
   int)':
IOBase.cpp:123: no matching function for call to `std::basic_fstream<char,
   std::char_traits<char> >::open(char*&, int&)'
d:/djgpp/lang/cxx-v3/bits/std_fstream.h:409: candidates are: void
   std::basic_fstream<_CharT, _Traits>::open(const char*, std::_Ios_Openmode =
   (std::ios_base::in | std::ios_base::out)) [with _CharT = char, _Traits =
   std::char_traits<char>]

Thanks a lot for your help.

Regards,
Y Chen

 //IOBase.cpp

#include <stdlib.h>
#include <stdio.h>
#include <iostream.h>
#include <iomanip.h>
#include <string.h>
#include <dirent.h>
#include <unistd.h> // e.g. sleep 
#include <termios.h> // struct termios
//#include <fcntl.h>
//#include <sys/param.h>
#include "IOBase.h"

///////////////////TIOBase
TIOBase::TIOBase() {
  pFile = new fstream();
}

TIOBase::~TIOBase() {
  delete pFile; // callls fstream::close
}

char TIOBase::OpenFile(char* acFilename, int aiMode) {
  // The calling function should  take care of closing  pFile, e.g
  // with CloseFile(). But we check if it is open.
#ifdef DEBUG
  cerr << " opening... " << acFilename
       << " rdstate: " << pFile->rdstate() << endl;
#endif
  if(!pFile) cerr << "pFile doesn't exist!" << endl;
  pFile->tellg(); // try to access it and wait for error.
#ifdef  DEBUG
  cerr << " Check if " << acFilename << " is already in use." << endl;
#endif
  if(!pFile->fail()) {
    cerr << "Warning: A file was already open (old file): " 
	 << acFilename << " (new file): " << acFilename;
    // So we clear and close it.
    pFile->clear(); pFile->close();
  }
  // keep the actual filename for messages
  strcpy(cFilename, acFilename); 
  // open the file. One can add an other parameter for the file-rights
  pFile->open(cFilename, aiMode);
  if(!pFile->good()) {
    cerr << " File not good : " << cFilename << " !\n";
    pFile->clear(); pFile->close();
    return 1;
  }
#ifdef DEBUG
  cerr << cFilename << " open.\n";
#endif
  return 0;
}

char TIOBase::CloseFile() {
  // check file. We use the ios statefalgs.
  iFileRdState = pFile->rdstate();
  // Also a EOF should not happen, it indicates that a file is not complete.
  if(!pFile->good()) { // && !pFile->eof()) { // !pFile->fail
    cerr << "File error before closing in " << cFilename << "\n"; 
    iFileRdState = 1;
  }
  // Clear in case of error and close file
  pFile->close();
#ifdef DEBUG
  cerr << "\n" << cFilename << " closed regularly.\n"; 
#endif
  strcpy(cFilename,"");
  if(iFileRdState) return 1; else return 0;
}

char TIOBase::ReadComment() {
  // skip comment (normally at the beginning of a file)
  if(!pFile) {
    cerr << "No File " << cFilename << " to read comment from.\n";
    return 1;
  }
  *pFile >> c;
  while((c == '#' || c == ' ' || c == '\n') && pFile->good()) {
#ifdef DEBUG
    cerr << c;
#endif    
    if(c == '#')
      if(c == '#') pFile->ignore(1000, '\n');
    *pFile >> c;
  }
  pFile->putback(c);
  if(pFile->eof()) { 
    cerr << "EOF while reading comment from " << cFilename << "\n"; 
    return 1; 
  }
  if(pFile->fail()) { 
    cerr << "FAIL while reading comment from " << cFilename << "\n"; 
    return 1; 
  }
#ifdef DEBUG 
  cerr << "\nComment read.\n";
#endif
  return 0;
}

char TIOBase::OpenFile(fstream *apFile, char* acFilename, int aiMode) {
  // The calling function should  take care of closing  apFile, e.g
  // with CloseFile(). But we check if it is open.
#ifdef DEBUG
  cerr << " opening... " << acFilename
       << " rdstate: " << apFile->rdstate() << endl;
#endif
  if(!apFile) cerr << "apFile doesn't exist!" << endl;
  apFile->tellg(); // try to access it and wait for error.
#ifdef  DEBUG
  cerr << " Check if " << acFilename << " is already in use." << endl;
#endif
  if(apFile->fail()) {
    cerr << "Warning: A file was already open (old file): " 
	 << acFilename << " (new file): " << acFilename;
    // So we clear and close it.
    apFile->clear(); apFile->close();
  }
  // open the file. One can add an other parameter for the file-rights
  apFile->open(acFilename, aiMode);
  if(!apFile->good()) {
    cerr << " File not good : " << acFilename << " !\n";
    apFile->clear(); apFile->close();
    return 1;
  }
#ifdef DEBUG
  cerr << acFilename << " open.\n";
#endif
  return 0;
}

char TIOBase::CloseFile(fstream *apFile) {
  // check file. We use the ios statefalgs.
  iFileRdState = apFile->rdstate();
  // Also a EOF should not happen, it indicates that a file is not complete.
  if(!apFile->good()) { // && !apFile->eof()) { // !apFile->fail
    cerr << "File error before closing in " << "\n"; 
    iFileRdState = 1;
  }
  // Clear in case of error and close file
  apFile->close();
#ifdef DEBUG
  cerr << "\n" << " closed regularly.\n"; 
#endif
  if(iFileRdState) return 1; else return 0;
}

bool TIOBase::DirContainsFile(bool SubSearch, char *fn) {
  DIR *dir;
  struct dirent *dr;
  dir = opendir(".");
  while(dr = readdir(dir)) {
    if(SubSearch) {
      if(strstr(dr->d_name, fn)) {
	closedir(dir); return 1; 
      }
    } else
      if(!strcmp(fn, dr->d_name)) {
	closedir(dir); return 1;
    }
  }
  closedir(dir);
  return 0;
}


int TIOBase::Keypressed(char &ac) {
  struct termios term, termsave;
  // We are not always in noncanonical mode without local echo, so if
  // a key is pressed "outside" this function (which is likely)
  // it will be echoed.
  // tty_noncanonical(STDIN_FILENO);
  if (tcgetattr(STDIN_FILENO, &termsave) < 0) cerr << "get error" << endl;
  term = termsave;
  term.c_lflag &= ~(ICANON | ECHO ); // noncanonical and no echo
  term.c_cc[VMIN] = 0; // buffer size
  term.c_cc[VTIME] = 0;
  if (tcsetattr(STDIN_FILENO, TCSANOW, &term) < 0) 
    cerr << "set error" << endl;  
  // Check for keypressed
  int iReturnValue = read(STDIN_FILENO, &ac, 1);
  // tty_reset(STDIN_FILENO);
  if (tcsetattr(STDIN_FILENO, TCSANOW, &termsave) < 0) 
    cerr << "set error" << endl;
  // Done. Return nuber of chars read.
  return iReturnValue;
}



//IOBase.h
#include <fstream.h>

/*** defines ***/
// switch for all debugging info
//#define DEBUG

/*** classes in this header ***/
class TIOBase; 

///////////////////TTIOBase
// a container class for trival common variables and functions.
// Handle the fileIO.
class TIOBase
{
public:
  // We leave the standart constructor empty, and do all the initializations
  // in the other one. The empty one is necessairy for TTopoCreator and
  // TPatternManager, becase their constructors are empty too. But as thier
  // classes exist only virtually for TRNN, the empty constructor of 
  // TIOBase will never be called. So no one will realize that it doesn't
  // do its work properly.
  TIOBase();
  ~TIOBase();
protected:
  // possible Mode parameters are defined in clsss ios (ios::out,in,...)
  // The childs are responsible closing and deleting the file again. 
  char OpenFile(char* acFilename, int aiMode);
  char OpenFile(fstream *apFile, char* acFilename, int aiMode);
  char CloseFile();
  char CloseFile(fstream *apFile);
  char ReadComment();
  bool DirContainsFile(bool SubSearch, char *fn);
  int Keypressed(char &ac);
  // Double to stream and the other way round.
  static void d2s(iostream *s, double &d) { *s << d; }
  static void s2d(iostream *s, double &d) { *s >> d; }
  // For long doubles.
  static void ld2s(iostream *s, long double &d) {
    double dd; dd=(double)d; *s << dd; } 
  static void s2ld(iostream *s, long double &d) {
    double dd; *s >> dd; d=dd; } 
  // We keep only one fstream object alive and open - close the files
  // instead of new - delete an fstream object every time we read a file.
  fstream *pFile; // common stream pointer for all childs
  long lFilePos; // to rescan the file begining after the global section
  char c;  // to read comments
private:
  char cFilename[101];
  int iFileRdState; // the status of the file.
};