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if( (p = (char *)malloc(0)) == NULL)
{
puts("NULL");
}
else
{
//printf("%d\n",sizeof(p));
printf("%d\n",strlen(p));
}
/***
*malloc.c - Get a block of memory from the heap
*
* Copyright (c) Microsoft Corporation. All rights reserved.
*
*Purpose:
* Defines the malloc() function.
*
*******************************************************************************/
#include <cruntime.h>
#include <malloc.h>
#include <internal.h>
#include <mtdll.h>
#include <dbgint.h>
#include <rterr.h>
#include <windows.h>
#include <winheap.h>
#include <rtcsup.h>
extern int _newmode; /* malloc new() handler mode */
#ifdef _DEBUG
#define _heap_alloc _heap_alloc_base
#endif /* _DEBUG */
/***
*void *_heap_alloc_base(size_t size) - does actual allocation
*
*Purpose:
* Same as malloc() except the new handler is not called.
*
*Entry:
* See malloc
*
*Exit:
* See malloc
*
*Exceptions:
*
*******************************************************************************/
__forceinline void * __cdecl _heap_alloc (size_t size)
{
if (_crtheap == 0) {
_FF_MSGBANNER(); /* write run-time error banner */
_NMSG_WRITE(_RT_CRT_NOTINIT); /* write message */
__crtExitProcess(255); /* normally _exit(255) */
}
return HeapAlloc(_crtheap, 0, size ? size : 1);
}
/***
*void *malloc(size_t size) - Get a block of memory from the heap
*
*Purpose:
* Allocate of block of memory of at least size bytes from the heap and
* return a pointer to it.
*
* Calls the new appropriate new handler (if installed).
*
*Entry:
* size_t size - size of block requested
*
*Exit:
* Success: Pointer to memory block
* Failure: NULL (or some error value)
*
*Uses:
*
*Exceptions:
*
*******************************************************************************/
void * __cdecl _malloc_base (size_t size)
{
void *res = NULL;
// validate size
if (size <= _HEAP_MAXREQ) {
for (;;) {
// allocate memory block
res = _heap_alloc(size);
// if successful allocation, return pointer to memory
// if new handling turned off altogether, return NULL
if (res != NULL)
{
break;
}
if (_newmode == 0)
{
errno = ENOMEM;
break;
}
// call installed new handler
if (!_callnewh(size))
break;
// new handler was successful -- try to allocate again
}
} else {
_callnewh(size);
errno = ENOMEM;
return NULL;
}
RTCCALLBACK(_RTC_Allocate_hook, (res, size, 0));
if (res == NULL)
{
errno = ENOMEM;
}
return res;
}