// ---------------------------------------------------------------
// File: Check_Memory_Demo.cpp
// Purpose: Demonstrate how to:
//			- Access Debug heap's state	
//			- Have the DCRT check memory functionality
//          to track memory leakks & overwrites. 
// Author: Divyanand Kutagulla, dkutagulla@hotmail.com 
// Source: Run-time library reference VS.NET 2003 help system
// Course: Software Testing Seminar,  Spring 2004
// ---------------------------------------------------------------


// 1 ---------------------------------------------------------
// Define _CRTDBG_MAP_ALLOC symbol before everything.
// This Symbol MUST be the first line in the file so that
// first during preprocessing even before any header files 
// (specified in the include directives) are processed.
// This define sets up the mapping of the 
// memory allocation and deallocation routines (malloc/new/
// free/delete) to the special debug versions that record 
// the file name and line number within the file where the 
// memory request was made
#define _CRTDBG_MAP_ALLOC
//---------------------------------------------------------


// 2 ------------------------------------------------------
// all the include files that we want to include go here
// after the _CRTDBG_MAP_ALLOC has been #defined above
#include "..\Common\myclass.h"
#include "..\Common\dcrt_setup.h"
#include <iostream>
//------------------------------------------------------

// 3 -----------------------------------------------------
// finally include the Debug C runtime header
#include <crtdbg.h>
//-----------------------------------------------------

#include <crtdbg.h>

// crt_set_security_error_handler.c
// compile with: /GS
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

void __cdecl report_failure(int code, void * unused)
{
   if(code == _SECERR_BUFFER_OVERRUN)
      printf("Buffer overrun detected! Program will end.\n");
   exit(1);
}

void vulnerable(const char *str)
{
   char buffer[10];
   strcpy(buffer, str); // overrun buffer !!!
}

void uninit_locals()
{
	int i;	//int i is uninitializecd and will be set to OxCCCC 
			//by compiler when the /RTCu is set...
	int j =i; //throw an exception during program execution
}

void truncate()
{
	int i  = 0xFFFF;
	char c = (i & 0xFF);  //correct way to initialize a char from an int without truncation
	
	//truncation is happening here.. when /RTCc is set up, 
	//a runtime error will be thrown when both these staments are executed...
	char w0 = (char)i;
	char w1 = i; 
	
}


int main()
{
	char large_buffer[] = "This string is longer than 10 characters!!!";
	//produce uninitialized  local variable runtime failure
	uninit_locals();
	//produce Datavalue truncation error
	truncate();
#ifdef CUSTOM_BUFFER_OVERRUN_HANLDER
	_set_security_error_handler(report_failure);
#endif
	vulnerable(large_buffer);
}