561 lines
18 KiB
C
561 lines
18 KiB
C
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/****************************************************************************
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*
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* Open Watcom Project
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*
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* Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
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*
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* ========================================================================
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*
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* This file contains Original Code and/or Modifications of Original
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* Code as defined in and that are subject to the Sybase Open Watcom
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* Public License version 1.0 (the 'License'). You may not use this file
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* except in compliance with the License. BY USING THIS FILE YOU AGREE TO
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* ALL TERMS AND CONDITIONS OF THE LICENSE. A copy of the License is
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* provided with the Original Code and Modifications, and is also
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* available at www.sybase.com/developer/opensource.
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*
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* The Original Code and all software distributed under the License are
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* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
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* EXPRESS OR IMPLIED, AND SYBASE AND ALL CONTRIBUTORS HEREBY DISCLAIM
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* ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR
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* NON-INFRINGEMENT. Please see the License for the specific language
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* governing rights and limitations under the License.
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*
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* ========================================================================
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*
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* Description: Heap growing routines - allocate near heap memory from OS.
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*
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****************************************************************************/
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//#include "dll.h" // needs to be first
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#include "variety.h"
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#include <stddef.h>
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#include <stdlib.h>
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#include <malloc.h>
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#include "heapacc.h"
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#include "heap.h"
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#include <errno.h>
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#if defined(__DOS_EXT__)
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// #include "extender.h"
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// #include "tinyio.h"
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#endif
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#if defined(__CALL21__)
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// #include "tinyio.h"
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#endif
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#if defined(__WINDOWS_286__) || defined(__NT__)
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void* _stdcall UserAlloc(int size);
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// #include "windows.h"
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#endif
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#if defined(__OS2__)
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// #include <wos2.h>
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#endif
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#if defined(__WINDOWS_386__)
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// extern void * pascal DPMIAlloc(unsigned long);
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#endif
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static frlptr __LinkUpNewMHeap( mheapptr );
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#if defined(__DOS_EXT__)
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extern int SegmentLimit();
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#pragma aux SegmentLimit = \
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"xor eax,eax" \
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"mov ax,ds" \
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"lsl eax,ax" \
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"inc eax" \
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value [eax] \
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modify exact [eax];
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static void __unlink( mheapptr miniheapptr )
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{
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mheapptr prev_link;
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mheapptr next_link;
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if( __nheapbeg == miniheapptr ) {
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__nheapbeg = miniheapptr->next;
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}
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if( miniheapptr == __MiniHeapRover ) {
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__MiniHeapRover = miniheapptr->prev;
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if( __MiniHeapRover == NULL ) {
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__MiniHeapRover = __nheapbeg;
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__LargestSizeB4MiniHeapRover = 0;
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}
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}
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if( miniheapptr == __MiniHeapFreeRover ) {
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__MiniHeapFreeRover = 0;
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}
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prev_link = miniheapptr->prev;
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next_link = miniheapptr->next;
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if( prev_link != NULL ) prev_link->next = next_link;
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if( next_link != NULL ) next_link->prev = prev_link;
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}
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void __FreeDPMIBlocks()
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{
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mheapptr mhp;
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struct dpmi_hdr *dpmi;
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mhp = __nheapbeg;
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while( mhp != NULL ) {
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// see if the last free entry has the full size of
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// the DPMI block ( - overhead). If it is then we can give this
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// DPMI block back to the DPMI host.
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if( (mhp->freehead.prev)->len + sizeof(struct miniheapblkp) ==
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mhp->len ) {
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mheapptr pnext;
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dpmi = ((struct dpmi_hdr *)mhp) - 1;
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pnext = mhp->next;
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__unlink( mhp );
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mhp = pnext;
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if( dpmi->dos_seg_value == 0 ) { // if DPMI block
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TinyDPMIFree( dpmi->dpmi_handle );
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} else { // else DOS block below 1MB
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TinyFreeBlock( dpmi->dos_seg_value );
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}
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} else {
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mhp = mhp->next;
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}
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}
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}
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void *__ReAllocDPMIBlock( frlptr p1, unsigned req_size )
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{
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mheapptr mhp;
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struct dpmi_hdr *dpmi;
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struct dpmi_hdr *prev_dpmi;
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unsigned size;
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frlptr flp, flp2;
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if( !__heap_enabled ) return( 0 );
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__FreeDPMIBlocks();
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prev_dpmi = NULL;
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for( mhp = __nheapbeg; mhp; mhp = mhp->next ) {
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if( ((PTR)mhp + sizeof(struct miniheapblkp) == (PTR)p1)
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&& (mhp->numalloc == 1) ) {
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// The mini-heap contains only this memblk
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__unlink( mhp );
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dpmi = ((struct dpmi_hdr *)mhp) - 1;
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if( dpmi->dos_seg_value != 0 ) return( NULL );
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size = mhp->len + sizeof(struct dpmi_hdr) + TAG_SIZE;
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size += ( req_size - (p1->len-TAG_SIZE) );
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size += 0x0fff;
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size &= ~0x0fff;
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prev_dpmi = dpmi;
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dpmi = TinyDPMIRealloc( dpmi, size );
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if( dpmi == NULL ) {
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dpmi = prev_dpmi;
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return( NULL ); // indicate resize failed
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}
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dpmi->dos_seg_value = 0;
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mhp = (mheapptr)( dpmi + 1 );
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mhp->len = size - sizeof(struct dpmi_hdr) - TAG_SIZE;
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flp = __LinkUpNewMHeap( mhp );
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mhp->numalloc = 1;
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// round up to even number
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req_size = (req_size + 1) & ~1;
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size = flp->len - req_size;
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if( size >= FRL_SIZE ) { // Enough to spare a free block
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flp->len = req_size | 1;// adjust size and set allocated bit
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// Make up a free block at the end
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flp2 = (frlptr)((PTR)flp + req_size);
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flp2->len = size | 1;
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++mhp->numalloc;
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mhp->largest_blk = 0;
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_nfree( (PTR)flp2 + TAG_SIZE );
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} else {
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flp->len |= 1; // set allocated bit
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}
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return( flp );
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}
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}
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return( NULL );
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}
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#endif
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static frlptr __LinkUpNewMHeap( mheapptr p1 ) // originally __AddNewHeap()
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{
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mheapptr p2;
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mheapptr p2_prev;
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tag *last_tag;
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unsigned amount;
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/* insert into ordered heap list (14-jun-91 AFS) */
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/* logic wasn't inserting heaps in proper ascending order */
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/* (09-nov-93 Fred) */
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p2_prev = NULL;
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for( p2 = __nheapbeg; p2 != NULL; p2 = p2->next ) {
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if( p1 < p2 ) break;
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p2_prev = p2;
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}
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/* ascending order should be: p2_prev < p1 < p2 */
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/* except for special cases when p2_prev and/or p2 are NULL */
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p1->prev = p2_prev;
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p1->next = p2;
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if( p2_prev != NULL ) {
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p2_prev->next = p1;
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} else { /* add p1 to beginning of heap */
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__nheapbeg = p1;
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}
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if( p2 != NULL ) {
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/* insert before 'p2' (list is non-empty) */
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p2->prev = p1;
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}
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amount = p1->len - sizeof( struct miniheapblkp );
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/* Fill out the new miniheap descriptor */
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p1->freehead.len = 0;
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p1->freehead.prev = &p1->freehead;
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p1->freehead.next = &p1->freehead;
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p1->rover = &p1->freehead;
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p1->b4rover = 0;
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p1->numalloc = 0;
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p1->numfree = 0;
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p1++;
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((frlptr)p1)->len = amount;
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/* fix up end of heap links */
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last_tag = (tag *) ( (PTR)p1 + amount );
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*last_tag = END_TAG;
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return( (frlptr) p1 );
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}
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#if ! ( defined(__WINDOWS_286__) || \
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defined(__WINDOWS_386__) || \
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defined(__WARP__) || \
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defined(__NT__) \
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)
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size_t __LastFree( void ) /* used by nheapgrow to know about adjustment */
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{
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frlptr p1;
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unsigned brk_value;
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if( __nheapbeg == NULL ) { /* no heap? can't have free blocks */
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return( 0 );
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}
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p1 = __nheapbeg->freehead.prev; /* point to last free block */
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brk_value = (unsigned)((PTR)p1 + p1->len + TAG_SIZE );
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#if defined(__DOS_EXT__)
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if( _IsPharLap() && !__X32VM) _curbrk = SegmentLimit(); /*19-feb-94*/
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#endif
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if( brk_value == _curbrk ) { /* if last free block is at the end */
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return( p1->len );
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}
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return( 0 );
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}
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#endif
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#if ! defined(__CALL21__)
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#if defined(__DOS_EXT__)
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static void *RationalAlloc( size_t size )
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{
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struct dpmi_hdr *dpmi;
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mheapptr mhp;
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tiny_ret_t save_DOS_block;
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tiny_ret_t DOS_block;
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__FreeDPMIBlocks();
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/* size is a multiple of 4k */
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dpmi = TinyDPMIAlloc( size );
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if( dpmi != NULL ) {
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mhp = (mheapptr)( dpmi + 1 );
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mhp->len = size - sizeof( struct dpmi_hdr );
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dpmi->dos_seg_value = 0; // indicate DPMI block
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return( (void *)mhp );
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}
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if( __minreal & 0xfff00000 ) {
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/* checks for users that want >1M real memory saved */
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__minreal = 0xfffff;
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}
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if( size > 0x00010000 ) {
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/* cannot allocate more than 64k from DOS real memory */
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return( NULL );
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}
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save_DOS_block = TinyAllocBlock(( __minreal >> 4 ) | 1 );
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if( TINY_OK( save_DOS_block ) ) {
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DOS_block = TinyAllocBlock( size >> 4 );
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TinyFreeBlock( save_DOS_block );
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if( TINY_OK( DOS_block ) ) {
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dpmi = (struct dpmi_hdr *) TinyDPMIBase( DOS_block );
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dpmi->dos_seg_value = DOS_block;
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mhp = (mheapptr)( dpmi + 1 );
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mhp->len = size - sizeof( struct dpmi_hdr );
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return( (void *)mhp );
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}
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}
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return( NULL );
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}
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#endif
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#endif
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static int __AdjustAmount( unsigned *amount )
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{
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unsigned old_amount = *amount;
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unsigned amt;
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#if ! ( defined(__WINDOWS_286__) || \
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defined(__WINDOWS_386__) || \
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defined(__WARP__) || \
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defined(__NT__) \
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)
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unsigned last_free_amt;
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#endif
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amt = old_amount;
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amt = ( amt + TAG_SIZE + ROUND_SIZE) & ~ROUND_SIZE;
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if( amt < old_amount ) {
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return( 0 );
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}
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#if ! ( defined(__WINDOWS_286__) || \
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defined(__WINDOWS_386__) || \
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defined(__WARP__) || \
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defined(__NT__) \
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)
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#if defined(__DOS_EXT__)
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if( _IsRationalZeroBase() || _IsCodeBuilder() ) {
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// Allocating extra to identify the dpmi block
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amt += sizeof(struct dpmi_hdr);
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} else {
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#else
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{
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#endif
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last_free_amt = __LastFree(); /* adjust for last free block */
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if( last_free_amt >= amt ) {
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amt = 0;
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} else {
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amt -= last_free_amt;
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}
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}
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#endif
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/* amount is even here */
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/*
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extra amounts (22-feb-91 AFS)
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(1) adding a new heap needs:
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frl free block req'd for _nmalloc request
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(frl is the MINIMUM because the block
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may be freed)
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tag end of miniheap descriptor
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struct miniheapblkp start of miniheap descriptor
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(2) extending heap needs:
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tag free block req'd for _nmalloc request
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*/
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*amount = amt;
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amt += ( (TAG_SIZE) + sizeof(frl) + sizeof(struct miniheapblkp) );
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if( amt < *amount ) return( 0 );
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if( amt < _amblksiz ) {
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/*
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_amblksiz may not be even so round down to an even number
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nb. pathological case: where _amblksiz == 0xffff, we don't
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want the usual round up to even
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*/
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amt = _amblksiz & ~1u;
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}
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#if defined(__WINDOWS_386__) || \
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defined(__WARP__) || \
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defined(__NT__) || \
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defined(__CALL21__) || \
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defined(__DOS_EXT__)
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/* make sure amount is a multiple of 4k */
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*amount = amt;
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amt += 0x0fff;
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if( amt < *amount ) return( 0 );
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amt &= ~0x0fff;
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#endif
|
||
|
|
*amount = amt;
|
||
|
|
return( *amount != 0 );
|
||
|
|
}
|
||
|
|
|
||
|
|
#if defined(__WINDOWS_286__) || \
|
||
|
|
defined(__WINDOWS_386__) || \
|
||
|
|
defined(__WARP__) || \
|
||
|
|
defined(__NT__) || \
|
||
|
|
defined(__CALL21__) || \
|
||
|
|
defined(__DOS_EXT__)
|
||
|
|
static int __CreateNewNHeap( unsigned amount )
|
||
|
|
{
|
||
|
|
mheapptr p1;
|
||
|
|
frlptr flp;
|
||
|
|
unsigned brk_value;
|
||
|
|
|
||
|
|
if( !__heap_enabled ) return( 0 );
|
||
|
|
if( _curbrk == ~1u ) return( 0 );
|
||
|
|
if( __AdjustAmount( &amount ) == 0 ) return( 0 );
|
||
|
|
#if defined(__WINDOWS_286__)
|
||
|
|
brk_value = (unsigned) LocalAlloc( LMEM_FIXED, amount );
|
||
|
|
if( brk_value == 0 ) {
|
||
|
|
return( 0 );
|
||
|
|
}
|
||
|
|
#elif defined(__WINDOWS_386__)
|
||
|
|
brk_value = (unsigned) DPMIAlloc( amount );
|
||
|
|
if( brk_value == 0 ) {
|
||
|
|
return( 0 );
|
||
|
|
}
|
||
|
|
#elif defined(__WARP__)
|
||
|
|
{
|
||
|
|
PBYTE p;
|
||
|
|
|
||
|
|
if( DosAllocMem( &p, amount, PAG_COMMIT|PAG_READ|PAG_WRITE ) ) {
|
||
|
|
return( 0 );
|
||
|
|
}
|
||
|
|
brk_value = (unsigned)p;
|
||
|
|
}
|
||
|
|
#elif defined(__NT__)
|
||
|
|
// brk_value = (unsigned) VirtualAlloc( NULL, amount, MEM_COMMIT,
|
||
|
|
// PAGE_EXECUTE_READWRITE );
|
||
|
|
brk_value = (unsigned) UserAlloc (amount );
|
||
|
|
|
||
|
|
//brk_value = (unsigned) LocalAlloc( LMEM_FIXED, amount );
|
||
|
|
if( brk_value == 0 ) {
|
||
|
|
return( 0 );
|
||
|
|
}
|
||
|
|
#elif defined(__CALL21__)
|
||
|
|
{
|
||
|
|
tag _WCNEAR *tmp_tag;
|
||
|
|
|
||
|
|
tmp_tag = (tag _WCNEAR *)TinyMemAlloc( amount );
|
||
|
|
if( tmp_tag == NULL ) {
|
||
|
|
return( 0 );
|
||
|
|
}
|
||
|
|
/* make sure it will not look like the end of a heap */
|
||
|
|
tmp_tag[0] = ! END_TAG;
|
||
|
|
brk_value = (unsigned) &tmp_tag[2];
|
||
|
|
amount -= 2 * TAG_SIZE; // 11-jun-95, subtract extra tag
|
||
|
|
}
|
||
|
|
#elif defined(__DOS_EXT__)
|
||
|
|
// if( _IsRationalZeroBase() || _IsCodeBuilder() ) {
|
||
|
|
{
|
||
|
|
tag *tmp_tag;
|
||
|
|
|
||
|
|
if( _IsRational() ) {
|
||
|
|
tmp_tag = RationalAlloc( amount );
|
||
|
|
if( tmp_tag ) amount = *tmp_tag;
|
||
|
|
} else { /* CodeBuilder */
|
||
|
|
tmp_tag = TinyCBAlloc( amount );
|
||
|
|
amount -= TAG_SIZE;
|
||
|
|
}
|
||
|
|
if( tmp_tag == NULL ) {
|
||
|
|
return( 0 );
|
||
|
|
}
|
||
|
|
brk_value = (unsigned) tmp_tag;
|
||
|
|
}
|
||
|
|
// Pharlap, RSI/non-zero can never call this function
|
||
|
|
#endif
|
||
|
|
if( amount - TAG_SIZE > amount ) {
|
||
|
|
return( 0 );
|
||
|
|
} else {
|
||
|
|
amount -= TAG_SIZE;
|
||
|
|
}
|
||
|
|
if( amount < sizeof( struct miniheapblkp ) + sizeof( frl ) ) {
|
||
|
|
/* there isn't enough for a heap block (struct miniheapblkp) and
|
||
|
|
one free block (frl) */
|
||
|
|
return( 0 );
|
||
|
|
}
|
||
|
|
/* we've got a new heap block */
|
||
|
|
p1 = (mheapptr) brk_value;
|
||
|
|
p1->len = amount;
|
||
|
|
// Now link it up
|
||
|
|
flp = __LinkUpNewMHeap( p1 );
|
||
|
|
amount = flp->len;
|
||
|
|
/* build a block for _nfree() */
|
||
|
|
flp->len = amount | 1;
|
||
|
|
++p1->numalloc; /* 28-dec-90 */
|
||
|
|
p1->largest_blk = 0;
|
||
|
|
_nfree( (PTR)flp + TAG_SIZE );
|
||
|
|
return( 1 );
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
int __ExpandDGROUP( unsigned amount )
|
||
|
|
{
|
||
|
|
#if defined(__WINDOWS_286__) || \
|
||
|
|
defined(__WINDOWS_386__) || \
|
||
|
|
defined(__WARP__) || \
|
||
|
|
defined(__NT__) || \
|
||
|
|
defined(__CALL21__)
|
||
|
|
// first try to free any available storage
|
||
|
|
_nheapshrink();
|
||
|
|
return( __CreateNewNHeap( amount ) );
|
||
|
|
#else
|
||
|
|
mheapptr p1;
|
||
|
|
frlptr flp;
|
||
|
|
unsigned brk_value;
|
||
|
|
tag *last_tag;
|
||
|
|
unsigned new_brk_value;
|
||
|
|
void _WCNEAR *brk_ret;
|
||
|
|
|
||
|
|
#if defined(__DOS_EXT__)
|
||
|
|
if( ( _IsRationalZeroBase() || _IsCodeBuilder() ) ) {
|
||
|
|
return( __CreateNewNHeap( amount ) ); // Won't slice either
|
||
|
|
}
|
||
|
|
// Rational non-zero based system should go through.
|
||
|
|
#endif
|
||
|
|
if( !__heap_enabled ) return( 0 );
|
||
|
|
if( _curbrk == ~1u ) return( 0 );
|
||
|
|
if( __AdjustAmount( &amount ) == 0 ) return( 0 );
|
||
|
|
#if defined(__DOS_EXT__)
|
||
|
|
if( _IsPharLap() && !__X32VM ) { /* 19-feb-94 */
|
||
|
|
_curbrk = SegmentLimit();
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
new_brk_value = amount + _curbrk;
|
||
|
|
if( new_brk_value < _curbrk ) {
|
||
|
|
new_brk_value = ~1u;
|
||
|
|
}
|
||
|
|
brk_ret = __brk( new_brk_value );
|
||
|
|
if( brk_ret == (void _WCNEAR *) -1 ) {
|
||
|
|
return( 0 );
|
||
|
|
}
|
||
|
|
brk_value = (unsigned) brk_ret;
|
||
|
|
if( brk_value > /*0xfff8*/ ~7u ) {
|
||
|
|
return( 0 );
|
||
|
|
}
|
||
|
|
if( new_brk_value <= brk_value ) {
|
||
|
|
return( 0 );
|
||
|
|
}
|
||
|
|
amount = new_brk_value - brk_value;
|
||
|
|
if( amount - TAG_SIZE > amount ) {
|
||
|
|
return( 0 );
|
||
|
|
} else {
|
||
|
|
amount -= TAG_SIZE;
|
||
|
|
}
|
||
|
|
for( p1 = __nheapbeg; p1 != NULL; p1 = p1->next ) {
|
||
|
|
if( p1->next == NULL ) break;
|
||
|
|
if( (unsigned)p1 <= brk_value &&
|
||
|
|
((unsigned)p1)+p1->len+TAG_SIZE >= brk_value ) break;
|
||
|
|
}
|
||
|
|
if( (p1 != NULL) &&
|
||
|
|
((brk_value - TAG_SIZE) == (unsigned)( (PTR)p1 + p1->len) ) ) {
|
||
|
|
/* we are extending the previous heap block (slicing) */
|
||
|
|
/* nb. account for the end-of-heap tag */
|
||
|
|
brk_value -= TAG_SIZE;
|
||
|
|
amount += TAG_SIZE;
|
||
|
|
flp = (frlptr) brk_value;
|
||
|
|
/* adjust current entry in heap list */
|
||
|
|
p1->len += amount;
|
||
|
|
/* fix up end of heap links */
|
||
|
|
last_tag = (tag *) ( (PTR)flp + amount );
|
||
|
|
last_tag[0] = END_TAG;
|
||
|
|
} else {
|
||
|
|
if( amount < sizeof( struct miniheapblkp ) + sizeof( frl ) ) {
|
||
|
|
/* there isn't enough for a heap block (struct miniheapblkp) and
|
||
|
|
one free block (frl) */
|
||
|
|
return( 0 );
|
||
|
|
}
|
||
|
|
// Initializing the near heap if __nheapbeg == NULL,
|
||
|
|
// otherwise, a new mini-heap is getting linked up
|
||
|
|
p1 = (mheapptr) brk_value;
|
||
|
|
p1->len = amount;
|
||
|
|
flp = __LinkUpNewMHeap( p1 );
|
||
|
|
amount = flp->len;
|
||
|
|
}
|
||
|
|
/* build a block for _nfree() */
|
||
|
|
flp->len = amount | 1;
|
||
|
|
++p1->numalloc; /* 28-dec-90 */
|
||
|
|
p1->largest_blk = ~0; /* set to largest value to be safe */
|
||
|
|
_nfree( (PTR)flp + TAG_SIZE );
|
||
|
|
return( 1 );
|
||
|
|
#endif
|
||
|
|
}
|