My compiler shuts down when I run this program...

I am using Turbo c++ 4.5, and everytime I run this program weird errors happen and sometimes it shuts down. Im going to replace the compiler but in the meantime I wanted to know if this program works for anyone else.

Code:

#include <iostream.h>
#include <string.h>

#ifndef BUFFER_H
#define BUFFER_H

//class Buffer
class Buffer {
public:
	Buffer();
	~Buffer();

	void Add(int Pos, char *b);
	void ClearBuff();
	void DisplayBuff();

private:
	char *a;
};

#endif

Buffer::Buffer()
{
	a = new char[1999];
}

Buffer::~Buffer()
{
	delete[] a;
}

void Buffer::Add(int Pos, char *b)
{
	int i = 0;

	for (i = 0; i < strlen(b); i++)
	{
		if (Pos+i > 1999 || Pos+i < 0)
			return;
		a[Pos+i] = b[i];
	}
}

void Buffer::ClearBuff()
{
	int i = 0;

	for (i = 0; i < 1999; i++)
		a[i] = ' ';
}

void Buffer::DisplayBuff()
{
	int i = 0;

	for (i = 0; i < 1999; i++)
		cout << a[i];
}

/******************************************************************************/

#ifndef ITEM_H
#define ITEM_H

// class Item
class Item {
public:
	Item();
	Item(char *a, float b);
	~Item();

	float GetPrice() { return Price; }
	char *GetName() { return Name; }

	void operator = (char *a);
	void operator = (float a) { Price = a; }

private:
	float Price;
	char *Name;
};

#endif

Item::Item(): Price(0.0f), Name(NULL)
{
}

Item::Item(char *a, float b): Price(b), Name(NULL)
{
	int i = 0;

	if (Name != NULL)
	{
		if (strlen(Name) == 1)
			delete Name;
		else
			delete[] Name;
	}

	Name = new char[ strlen(a) + 1 ];

	for (i = 0; i < strlen(a); i++)
		Name[i] = a[i];
}

Item::~Item()
{
	if (Name != NULL)
	{
		if (strlen(Name) == 1)
			delete Name;
		else
			delete[] Name;
	}
}

void Item::operator = (char *a)
{
	int i = 0;

	if (Name != NULL)
	{
		if (strlen(Name) == 1)
			delete Name;
		else
			delete[] Name;
	}

	Name = new char[ strlen(a) + 1];

	for (i = 0; i < strlen(a); i++)
		Name[i] = a[i];
}

/******************************************************************************/

int xytobuff(int x, int y);
void AddtoBuff(Buffer a, Item *b);

int main()
{
	Buffer a;
	Item b[5];

	b[0] = "Zanahoria";
	b[0] = 16.00;
	b[1] = "Papa";
	b[1] = 19.90;
	b[2] = "Cebolla";
	b[2] = 9.00;
	b[3] = "Pepino";
	b[3] = 12.50;
	b[4] = "Papaya";
	b[4] = 16.00;
	b[5] = "Sandia";
	b[5] = 26.90;

	a.ClearBuff();
	AddtoBuff(a, b);
	a.DisplayBuff();

	return 0;
}

int xytobuff(int x, int y)
{
	return x + y * 80;
}

void AddtoBuff(Buffer a, Item *b)
{
	int x = 5, y = 1;
	int i = 0;

	while (i < 5)
	{
		a.Add(xytobuff(x, y), b[i].GetName());
		y++;
		i++;
	}
}

I know somethings look stupid but I was just messing around triying to fix it, maybe sometimes I dont free the memory or something like that.

Sounds like there is invalid memory access issue and the OS is set to reboot upon such an application error.

Kuphryn

Your deletes are wrong for starters
Even if you do new char[1], you still need to do delete[ ]

Basically, you don't need all those if tests in front of all you deletes


> b[5] = "Sandia";
> b[5] = 26.90;
You only have b[5], so these are off the end of the array.
Delete them, or say Item b[6]

Thanks very much for the help, I corrected those mistakes and now it runs, but there still seems to be some kind of memory miss reading/writing because I get this kind of output:

Papa(WeirdCharacters)
Zanahoria(Weird Characters)

and so on, The characters are totally random and sometimes they dont appear. Too bad I dont understand the debugger for this compiler.

Code:

void Buffer::Add(int Pos, char *b)
{
	int i = 0;

	for (i = 0; i < strlen(b); i++)
	{
		if (Pos+i > 1999 || Pos+i < 0)
			return;
		a[Pos+i] = b[i];
	}
}

You're off by one here. That should be:

Code:

if (Pos+i >= 1999 || Pos+i < 0)

Worse, you are not null terminating the name string:

Code:

void Item::operator = (char *a)
{
	int i;

	delete[] Name;

	Name = new char[ strlen(a) + 1];

	for (i = 0; i < strlen(a); i++)
		Name[i] = a[i];
}

You never add a null terminator so the name string is not correctly null terminated. Therefore, the name string continues into random memory. This may crash your program or it may simply continue into random memory until it finds a null terminator.

Oh man really thanks a lot, that corrected it all.