0,0 → 1,256 |
/**************************************************************************** |
* |
* Open Watcom Project |
* |
* Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved. |
* |
* ======================================================================== |
* |
* This file contains Original Code and/or Modifications of Original |
* Code as defined in and that are subject to the Sybase Open Watcom |
* Public License version 1.0 (the 'License'). You may not use this file |
* except in compliance with the License. BY USING THIS FILE YOU AGREE TO |
* ALL TERMS AND CONDITIONS OF THE LICENSE. A copy of the License is |
* provided with the Original Code and Modifications, and is also |
* available at www.sybase.com/developer/opensource. |
* |
* The Original Code and all software distributed under the License are |
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER |
* EXPRESS OR IMPLIED, AND SYBASE AND ALL CONTRIBUTORS HEREBY DISCLAIM |
* ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF |
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR |
* NON-INFRINGEMENT. Please see the License for the specific language |
* governing rights and limitations under the License. |
* |
* ======================================================================== |
* |
* Description: Implementation of near _heapmin() and _nheapmin(). |
* |
****************************************************************************/ |
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//#include "dll.h" // needs to be first |
#include "variety.h" |
#include <stddef.h> |
#include <stdlib.h> |
#include <malloc.h> |
#include "heap.h" |
#include "heapacc.h" |
#if defined(__DOS_EXT__) |
// #include "extender.h" |
#endif |
#if defined(__WINDOWS_286__) || defined(__NT__) |
int _stdcall UserFree(void* p); |
// #include "windows.h" |
#endif |
#if defined(__OS2__) |
// #include <wos2.h> |
#endif |
#if defined(__WINDOWS_386__) |
// extern int __pascal DPMIFree(unsigned long); // windows extender function |
#endif |
#if defined(__CALL21__) |
// #include "tinyio.h" |
#endif |
|
#if defined(__SMALL_DATA__) |
|
_WCRTLINK int _heapshrink( void ) |
{ |
return( _nheapshrink() ); |
} |
|
_WCRTLINK int _heapmin( void ) |
{ |
return( _nheapshrink() ); |
} |
|
#endif |
|
_WCRTLINK int _nheapmin( void ) |
{ |
return( _nheapshrink() ); |
} |
|
#if defined(__WARP__) || \ |
defined(__WINDOWS_286__) || \ |
defined(__WINDOWS_386__) || \ |
defined(__NT__) || \ |
defined(__CALL21__) |
static int __ReturnMemToSystem( mheapptr mhp ) |
{ |
mheapptr pnext; |
|
pnext = mhp->next; |
#if defined(__WARP__) |
if( DosFreeMem( (PBYTE)mhp ) ) return( -1 ); |
#elif defined(__NT__) |
//if( LocalFree( (HLOCAL)mhp ) != NULL ) return( -1 ); |
// if (!VirtualFree(mhp, 0, MEM_RELEASE)) |
// return -1; |
if(!UserFree(mhp)) |
return -1; |
|
#elif defined(__WINDOWS_386__) |
if( DPMIFree( (unsigned long)mhp ) != 0 ) return( -1 ); |
#elif defined(__WINDOWS_286__) |
if( LocalFree( (HLOCAL)mhp ) != NULL ) return( -1 ); |
#elif defined(__CALL21__) |
// No way to free storage under OSI |
if( mhp ) return( -1 ); |
#endif |
if( __MiniHeapRover == mhp ) { // Update rovers |
if( pnext ) { |
__MiniHeapRover = pnext; |
} else { |
__MiniHeapRover = __nheapbeg; |
__LargestSizeB4MiniHeapRover = 0; |
} |
} |
if( __MiniHeapFreeRover == mhp ) { |
__MiniHeapFreeRover = 0; |
} |
return( 0 ); // success |
} |
|
static void __ReleaseMiniHeap( mheapptr mhp ) |
{ |
mheapptr pprev; |
mheapptr pnext; |
|
pprev = mhp->prev; |
pnext = mhp->next; |
if( __ReturnMemToSystem( mhp ) == 0 ) { |
if( pprev == NULL ) { |
__nheapbeg = pnext; |
} else { |
pprev->next = pnext; |
} |
if( pnext != NULL ) pnext->prev = pprev; |
} //else: do not unlink if the memory cannot be freed successfully |
} |
|
#endif |
|
_WCRTLINK int _nheapshrink( void ) |
{ |
mheapptr mhp; |
#if !defined(__WARP__) && \ |
!defined(__WINDOWS_286__) && \ |
!defined(__WINDOWS_386__) && \ |
!defined(__NT__) && \ |
!defined(__CALL21__) |
// Shrink by adjusting _curbrk |
|
frlptr last_free; |
frlptr end_tag; |
unsigned new_brk; |
|
_AccessNHeap(); |
#if defined(__DOS_EXT__) |
if( !_IsRationalZeroBase() && !_IsCodeBuilder() ) { |
#endif |
if( __nheapbeg == NULL ) { |
_ReleaseNHeap(); |
return( 0 ); // No near heap, can't shrink |
} |
/* Goto the end of miniheaplist (if there's more than 1 blk) */ |
for( mhp = __nheapbeg; mhp->next; mhp = mhp->next ); |
/* check that last free block is at end of heap */ |
last_free = mhp->freehead.prev; |
end_tag = (frlptr) ( (PTR)last_free + last_free->len ); |
if( end_tag->len != END_TAG ) { |
_ReleaseNHeap(); |
return( 0 ); |
} |
if( end_tag != (frlptr) ((PTR)mhp + mhp->len ) ) { |
_ReleaseNHeap(); |
return( 0 ); |
} |
#if defined(__DOS_EXT__) |
// only shrink if we can shave off at least 4k |
if( last_free->len < 0x1000 ) { |
_ReleaseNHeap(); |
return( 0 ); |
} |
#else |
if( last_free->len <= sizeof( frl ) ) { |
_ReleaseNHeap(); |
return( 0 ); |
} |
#endif |
/* make sure there hasn't been an external change in _curbrk */ |
if( sbrk( 0 ) != &(end_tag->prev) ) { |
_ReleaseNHeap(); |
return( 0 ); |
} |
/* calculate adjustment factor */ |
if( mhp->len-last_free->len > sizeof( struct miniheapblkp ) ) { |
// this miniheapblk is still being used |
#if defined(__DOS_EXT__) |
frlptr new_last_free; |
new_last_free = (frlptr)((((unsigned)last_free + 0xfff) & ~0xfff) - TAG_SIZE); |
if( new_last_free == last_free ) { |
#endif |
// remove entire entry |
mhp->len -= last_free->len; |
--mhp->numfree; |
// Relink the freelist entries, and update the rover |
mhp->freehead.prev = last_free->prev; |
last_free->prev->next = &mhp->freehead; |
if( mhp->rover == last_free ) mhp->rover = last_free->prev; |
#if defined(__DOS_EXT__) |
} else { |
// just shrink the last free entry |
mhp->len -= last_free->len; |
last_free->len = (PTR)new_last_free - (PTR)last_free; |
mhp->len += last_free->len; |
last_free = new_last_free; |
} |
#endif |
last_free->len = END_TAG; |
new_brk = (unsigned) ((PTR)last_free + TAG_SIZE ); |
} else { |
// we can remove this miniheapblk |
if( mhp->prev ) { // Not the first miniheapblk |
mhp->prev->next = NULL; |
new_brk = (unsigned)mhp;//->prev + (unsigned)mhp->prev->len; |
} else { // Is the first miniheapblk |
new_brk = (unsigned)__nheapbeg; |
__nheapbeg = NULL; |
} |
// Update rover info |
if( __MiniHeapRover == mhp ) { |
__MiniHeapRover = __nheapbeg; |
__LargestSizeB4MiniHeapRover = 0; |
} |
} |
|
if( __brk( new_brk ) == (void _WCNEAR *) -1 ) { |
_ReleaseNHeap(); |
return( -1 ); |
} |
_ReleaseNHeap(); |
return( 0 ); |
#if defined(__DOS_EXT__) |
} |
__FreeDPMIBlocks(); // For RSI/zero-base and Intel CB |
_ReleaseNHeap(); |
return( 0 ); |
#endif |
#else |
// Shrink by releasing mini-heaps |
{ |
mheapptr pnext; |
|
_AccessNHeap(); |
for( mhp = __nheapbeg; mhp; mhp = pnext ) { |
pnext = mhp->next; |
if( mhp->len - sizeof(struct miniheapblkp) == |
(mhp->freehead.prev)->len ) __ReleaseMiniHeap( mhp ); |
} |
_ReleaseNHeap(); |
return( 0 ); |
} |
#endif |
} |