| 0,0 → 1,256 |
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| /**************************************************************************** |
| * |
| * 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(). |
| * |
| ****************************************************************************/ |
| |
| |
| //#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 |
| } |