_WCRTLINK void _nheapgrow( void )
{
#if defined( __WINDOWS_286__ ) || !defined( _M_I86 )
_nfree( _nmalloc( 1 ) ); /* get something into the heap */
#else
unsigned max_paras;
unsigned curr_paras;
unsigned diff_paras;
unsigned expand;
_AccessNHeap();
/* calculate # pages which always has extra slack space (ie. 0x10) */
curr_paras = (( _curbrk + 0x10 ) & ~0x0f ) >> 4;
if( curr_paras == 0 ) {
/* we're already at 64k */
_ReleaseNHeap();
return;
}
#if defined(__QNX__)
if( qnx_segment_realloc( _DGroup(), 65536L ) == -1 ) {
_ReleaseNHeap();
return;
}
max_paras = PARAS_IN_64K;
#elif defined(__OS2__)
if( DosReallocSeg( 0, _DGroup() ) ) {
_ReleaseNHeap();
return;
}
max_paras = PARAS_IN_64K;
#else
if( _RWD_osmode != DOS_MODE ) { /* 23-apr-91 */
max_paras = PARAS_IN_64K;
} else {
max_paras = TinyMaxSet( _RWD_psp );
/* subtract off code size */
max_paras -= _DGroup() - _RWD_psp;
if( max_paras > PARAS_IN_64K ) {
max_paras = PARAS_IN_64K;
}
}
#endif
if( max_paras <= curr_paras ) {
/* '<' -> something is wrong, '==' -> can't change size */
_ReleaseNHeap();
return;
}
diff_paras = max_paras - curr_paras;
expand = (( diff_paras + 1 ) << 4 ) - ( _curbrk & 0x0f );
expand += __LastFree(); /* compensate for _expand's adjustment */
_ReleaseNHeap();
_nfree( _nmalloc( expand - ( sizeof( size_t ) + sizeof(frl) ) ) );
#endif
}
static int __AdjustAmount( unsigned *amount )
{
unsigned old_amount = *amount;
unsigned amt;
#if !( defined(__WINDOWS__) || defined(__WARP__) || defined(__NT__) )
unsigned last_free_amt;
#endif
amt = old_amount;
amt = __ROUND_UP_SIZE( amt + TAG_SIZE, ROUND_SIZE );
if( amt < old_amount ) {
return( 0 );
}
#if !( defined(__WINDOWS__) || defined(__WARP__) || defined(__NT__) )
#if defined(__DOS_EXT__)
if( !__IsCtsNHeap() ) {
// Allocating extra to identify the dpmi block
amt += sizeof( dpmi_hdr );
} else {
#endif
last_free_amt = __LastFree(); /* adjust for last free block */
if( last_free_amt >= amt ) {
amt = 0;
} else {
amt -= last_free_amt;
}
#if defined(__DOS_EXT__)
}
#endif
#endif
/* amount is even here */
/*
extra amounts (22-feb-91 AFS)
(1) adding a new heap needs:
frl free block req'd for _nmalloc request
(frl is the MINIMUM because the block
may be freed)
tag end of miniheap descriptor
struct miniheapblkp start of miniheap descriptor
(2) extending heap needs:
tag free block req'd for _nmalloc request
*/
*amount = amt;
amt += ( (TAG_SIZE) + sizeof( frl ) + sizeof( miniheapblkp ) );
if( amt < *amount )
return( 0 ); // Report request too large
if( amt < _amblksiz ) {
/*
_amblksiz may not be even so round down to an even number
nb. pathological case: where _amblksiz == 0xffff, we don't
want the usual round up to even
*/
amt = __ROUND_DOWN_SIZE( _amblksiz, 2 );
}
#if defined(__WINDOWS_386__) || defined(__WARP__) || defined(__NT__) \
|| defined(__CALL21__) || defined(__DOS_EXT__) || defined(__RDOS__)
/* make sure amount is a multiple of 4k/64k */
*amount = amt;
amt = __ROUND_UP_SIZE( amt, BLKSIZE_ALIGN );
if( amt < *amount )
return( 0 );
#endif
*amount = amt;
return( *amount != 0 );
}
static int __AdjustAmount( unsigned *amount )
{
unsigned old_amount = *amount;
unsigned amt;
#if ! ( defined(__WINDOWS_286__) || \
defined(__WINDOWS_386__) || \
defined(__WARP__) || \
defined(__NT__) \
)
unsigned last_free_amt;
#endif
amt = old_amount;
amt = ( amt + TAG_SIZE + ROUND_SIZE) & ~ROUND_SIZE;
if( amt < old_amount ) {
return( 0 );
}
#if ! ( defined(__WINDOWS_286__) || \
defined(__WINDOWS_386__) || \
defined(__WARP__) || \
defined(__NT__) \
)
#if defined(__DOS_EXT__)
if( _IsRationalZeroBase() || _IsCodeBuilder() ) {
// Allocating extra to identify the dpmi block
amt += sizeof(struct dpmi_hdr);
} else {
#else
{
#endif
last_free_amt = __LastFree(); /* adjust for last free block */
if( last_free_amt >= amt ) {
amt = 0;
} else {
amt -= last_free_amt;
}
}
#endif
/* amount is even here */
/*
extra amounts (22-feb-91 AFS)
(1) adding a new heap needs:
frl free block req'd for _nmalloc request
(frl is the MINIMUM because the block
may be freed)
tag end of miniheap descriptor
struct miniheapblkp start of miniheap descriptor
(2) extending heap needs:
tag free block req'd for _nmalloc request
*/
*amount = amt;
amt += ( (TAG_SIZE) + sizeof(frl) + sizeof(struct miniheapblkp) );
if( amt < *amount ) return( 0 );
if( amt < _amblksiz ) {
/*
_amblksiz may not be even so round down to an even number
nb. pathological case: where _amblksiz == 0xffff, we don't
want the usual round up to even
*/
amt = _amblksiz & ~1u;
}
#if defined(__WINDOWS_386__) || \
defined(__WARP__) || \
defined(__NT__) || \
defined(__CALL21__) || \
defined(__DOS_EXT__) || \
defined(__RDOS__)
/* make sure amount is a multiple of 4k */
*amount = amt;
amt += 0x0fff;
if( amt < *amount ) return( 0 );
amt &= ~0x0fff;
#endif
*amount = amt;
return( *amount != 0 );
}
#if defined(__WINDOWS_286__) || \
defined(__WINDOWS_386__) || \
defined(__WARP__) || \
defined(__NT__) || \
defined(__CALL21__) || \
defined(__DOS_EXT__) || \
defined(__RDOS__)
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( (PPVOID)&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) 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
#elif defined(__RDOS__)
brk_value = (unsigned) RdosAllocateMem( amount );
if( brk_value == 0 ) {
return( 0 );
}
#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 );
}
