CPP/Common/NewHandler.h


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// Common/NewHandler.h

#ifndef __COMMON_NEW_HANDLER_H
#define __COMMON_NEW_HANDLER_H

/*
NewHandler.h and NewHandler.cpp allows to solve problem with compilers that
don't throw exception in operator new().

This file must be included before any code that uses operators new() or delete()
and you must compile and link "NewHandler.cpp", if you use some old MSVC compiler.

The operator new() in some MSVC versions doesn't throw exception std::bad_alloc.
MSVC 6.0 (_MSC_VER == 1200) doesn't throw exception.
The code produced by some another MSVC compilers also can be linked
to library that doesn't throw exception.
We suppose that code compiled with VS2015+ (_MSC_VER >= 1900) throws exception std::bad_alloc.
For older _MSC_VER versions we redefine operator new() and operator delete().
Our version of operator new() throws CNewException() exception on failure.

It's still allowed to use redefined version of operator new() from "NewHandler.cpp"
with any compiler. 7-Zip's code can work with std::bad_alloc and CNewException() exceptions.
But if you use some additional code (outside of 7-Zip's code), you must check
that redefined version of operator new() is not problem for your code.
*/

#include <stddef.h>

#ifdef _WIN32
// We can compile my_new and my_delete with _fastcall
/*
void * my_new(size_t size);
void my_delete(void *p) throw();
// void * my_Realloc(void *p, size_t newSize, size_t oldSize);
*/
#endif


#if defined(_MSC_VER) && (_MSC_VER < 1900)
  // If you want to use default operator new(), you can disable the following line
  #define _7ZIP_REDEFINE_OPERATOR_NEW
#endif


#ifdef _7ZIP_REDEFINE_OPERATOR_NEW

// std::bad_alloc can require additional DLL dependency.
// So we don't define CNewException as std::bad_alloc here.

class CNewException {};

void *
#ifdef _MSC_VER
__cdecl
#endif
operator new(size_t size);

void
#ifdef _MSC_VER
__cdecl
#endif
operator delete(void *p) throw();

#else

#include <new>

#define CNewException std::bad_alloc

#endif

/*
#ifdef _WIN32
void *
#ifdef _MSC_VER
__cdecl
#endif
operator new[](size_t size);

void
#ifdef _MSC_VER
__cdecl
#endif
operator delete[](void *p) throw();
#endif
*/

#endif