diskfile.cpp

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// DiskFile.cpp: implementation of the DiskFile class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "DiskFile.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

DiskFile::DiskFile(const char *fname=NULL,const char *mode=NULL):FileDescriptor(PFILE)
{
	/*
	char modestr[4]={0};
	if(mode&READ&&mode&~WRITE&&mode&~APPEND)
		strcat(modestr,"r");
	else if(mode&~READ&&mode&WRITE&&mode&~APPEND)
		strcat(modestr,"w");
	else if(mode&~READ&&mode&~WRITE&&mode&APPEND)
		strcat(modestr,"a");
	else
		strcat(modestr,"r"); //default is read only
	if(mode&~BITFORMAT)
		strcat(modestr,"")
		*/
	f = NULL;
	this->open(fname,mode);
}

DiskFile::~DiskFile()
{
	close();
}

bool DiskFile::open(const char *fname,const char *mode)
{
	status = CLOSED;
	f = fopen(fname,mode);
	if(!f)
		return false;
	status = OPEN;
	return true;
}

int DiskFile::write(const void* aBuffer, int aLen)
{
	int i = -1;
	if(f&&aLen>0&&aBuffer)
	{
		i = fwrite(aBuffer,sizeof(char),aLen,f);
        if(i!=aLen&&ferror(f)!=0)
		{
			i = FILE_ERROR;
			setLastError(ferror(f));
		}
	}
	return i;
}

int DiskFile::read(void* aBuffer, int aBufLen)
{
	int i = -1;
		
	if(f&&aBuffer&&aBufLen>0)
	{
		i = fread(aBuffer,sizeof(char),aBufLen,f);
		if(i==0&&feof(f))
			i = FILE_EOF;
		else if(i!=aBufLen&&ferror(f)!=0)
		{
			i = FILE_ERROR;
			setLastError(ferror(f));
		}
	}
	return i;
}


void DiskFile::close()
{
	status = CLOSED;
	if(f)
		fclose(f);
	f = NULL;
}


int DiskFile::getLastError()
{
	return err;
}


void DiskFile::setLastError(int errCode)
{
	err =  errCode;
}

long DiskFile::size()
{
	if(f)
	{
		fseek(f,0L,SEEK_SET);
		long start = ftell(f);
		fseek(f,0L,SEEK_END);
		long end = ftell(f);
		return end-start+1;
	}
	return -1;
}