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/***
*expand.c - Win32 expand heap routine** Copyright (c) 1991-2001, Microsoft Corporation. All rights reserved.**Purpose:**Revision History:* 01-15-92 JCR Module created.* 02-04-92 GJF Replaced windows.h with oscalls.h.* 05-06-92 DJM ifndef out of POSIX build.* 09-23-92 SRW Change winheap code to call NT directly always* 10-15-92 SKS Removed the ill-named HEAP_GROWTH_ALLOWED flag* which was causing a bug: _expand was behaving like* realloc(), by moving the block when it could not be* grown in place. _expand() must NEVER move the block.* Also added a safety check to work around a bug in* HeapReAlloc, where it returns success even* when it fails to grow the block in place.* 10-28-92 SRW Change winheap code to call Heap????Ex calls* 11-05-92 SKS Change name of variable "CrtHeap" to "_crtheap"* 11-07-92 SRW _NTIDW340 replaced by linkopts\betacmp.c* 11-16-92 SRW Heap???Ex functions renamed to Heap???* 10-21-93 GJF Replace _CALLTYPE1 with _cdecl. Cleaned up format.* 04-06-95 GJF Added support for debug heap.* 04-29-95 GJF Copied over from winheap and made conditional on* WINHEAP.* 05-22-95 GJF Test against _HEAP_MAXREQ before calling API. Also,* removed workaround for long-ago NT problem.* 05-24-95 CFW Official ANSI C++ new handler added.* 05-23-95 GJF Really removed workaround this time...* 03-04-96 GJF Added support for small-block heap. Moved heaphook* invocation to the very start of the function.* 04-10-96 GJF Return type of __sbh_find_block and __sbh_resize_block* changed to __map_t *.* 05-30-96 GJF Minor changes for latest version of small-block heap.* 05-22-97 RDK New small-block heap scheme implemented.* 09-26-97 BWT Fix POSIX* 11-05-97 GJF Small POSIX fix from Roger Lanser.* 12-17-97 GJF Exception-safe locking.* 07-28-98 JWM RTC update.* 09-29-98 GJF Bypass all small-block heap code when __sbh_initialized* is 0.* 11-16-98 GJF Merged in VC++ 5.0 version of small-block heap.* 12-02-98 GJF One too many munlocks!* 12-18-98 GJF Changes for 64-bit size_t.* 05-01-99 PML Disable small-block heap for Win64.* 05-26-99 KBF Updated RTC hook func params* 06-21-99 GJF Removed old small-block heap from static libs.* 08-04-00 PML Don't round allocation sizes when using system* heap (VS7#131005).********************************************************************************/
#ifdef WINHEAP
#include <cruntime.h>
#include <malloc.h>
#include <winheap.h>
#include <windows.h>
#include <mtdll.h>
#include <dbgint.h>
#include <rtcsup.h>
/***
*void *_expand(void *pblck, size_t newsize) - expand/contract a block of memory* in the heap**Purpose:* Resizes a block in the heap to newsize bytes. newsize may be either* greater (expansion) or less (contraction) than the original size of* the block. The block is NOT moved.** NOTES:** (1) In this implementation, if the block cannot be grown to the* desired size, the resulting block will NOT be grown to the max* possible size. (That is, either it works or it doesn't.)** (2) Unlike other implementations, you can NOT pass a previously* freed block to this routine and expect it to work.**Entry:* void *pblck - pointer to block in the heap previously allocated* by a call to malloc(), realloc() or _expand().** size_t newsize - requested size for the resized block**Exit:* Success: Pointer to the resized memory block (i.e., pblck)* Failure: NULL**Uses:**Exceptions:* If pblck does not point to a valid allocation block in the heap,* _expand() will behave unpredictably and probably corrupt the heap.********************************************************************************/
void * __cdecl _expand_base (void * pBlock, size_t newsize){#ifdef _POSIX_
return (HeapReAlloc( _crtheap, HEAP_REALLOC_IN_PLACE_ONLY, pBlock, (DWORD)newsize ));#else
void * pvReturn;
#ifdef HEAPHOOK
/* call heap hook if installed */ if (_heaphook) { void * pvReturn; if ((*_heaphook)(_HEAP_EXPAND, newsize, pBlock, (void *)&pvReturn)) return pvReturn; }#endif /* HEAPHOOK */
/* validate size */ if ( newsize > _HEAP_MAXREQ ) return NULL;
#ifndef _WIN64
if ( __active_heap == __V6_HEAP ) { PHEADER pHeader;
#ifdef _MT
_mlock( _HEAP_LOCK ); __try {#endif
// if allocation block lies within the small-block heap,
// try to resize it there
if ((pHeader = __sbh_find_block(pBlock)) != NULL) { pvReturn = NULL; if ( (newsize <= __sbh_threshold) && __sbh_resize_block(pHeader, pBlock, (int)newsize) ) pvReturn = pBlock; }
#ifdef _MT
} __finally { _munlock( _HEAP_LOCK ); }#endif
if ( pHeader == NULL ) { // force nonzero size and round up to next paragraph
if (newsize == 0) newsize = 1; newsize = (newsize + BYTES_PER_PARA - 1) & ~(BYTES_PER_PARA - 1);
pvReturn = HeapReAlloc(_crtheap, HEAP_REALLOC_IN_PLACE_ONLY, pBlock, newsize); } }#ifdef CRTDLL
else if ( __active_heap == __V5_HEAP ) { __old_sbh_region_t *preg; __old_sbh_page_t * ppage; __old_page_map_t * pmap;
// force nonzero size and round up to next paragraph
if (newsize == 0) newsize = 1; newsize = (newsize + _OLD_PARASIZE - 1) & ~(_OLD_PARASIZE - 1);#ifdef _MT
_mlock(_HEAP_LOCK); __try {#endif
pmap = __old_sbh_find_block(pBlock, &preg, &ppage);
// allocation block lies within the small-block heap, try to resize
// it there.
if ( pmap != NULL ) { // *pBlock lies within the small-block heap, try to resize it
// there
pvReturn = NULL; if ( (newsize <= __old_sbh_threshold) && __old_sbh_resize_block(preg, ppage, pmap, newsize >> _OLD_PARASHIFT) ) pvReturn = pBlock;
RTCCALLBACK(_RTC_Free_hook, (pBlock, 0)); RTCCALLBACK(_RTC_Allocate_hook, (pvReturn, newsize, 0)); return pvReturn; }
#ifdef _MT
} __finally { _munlock(_HEAP_LOCK); }#endif
if ( pmap == NULL ) pvReturn = HeapReAlloc(_crtheap, HEAP_REALLOC_IN_PLACE_ONLY, pBlock, newsize); }#endif /* CRTDLL */
else // __active_heap == __SYSTEM_HEAP
#endif /* ndef _WIN64 */
{ // force nonzero size
if (newsize == 0) newsize = 1;
pvReturn = HeapReAlloc(_crtheap, HEAP_REALLOC_IN_PLACE_ONLY, pBlock, newsize);
}
if (pvReturn) { RTCCALLBACK(_RTC_Free_hook, (pBlock, 0)); RTCCALLBACK(_RTC_Allocate_hook, (pvReturn, newsize, 0)); }
return pvReturn;#endif /* _POSIX_ */
}
#endif /* WINHEAP */
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