;*****************************************************************************
;*
;* 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: WHEN YOU FIGURE OUT WHAT THIS FILE DOES, PLEASE
;* DESCRIBE IT HERE!
;*
;*****************************************************************************
include mdef.inc
include struct.inc
include xinit.inc
include exitwmsg.inc
modstart stk
datasegment
extrn "C",_STACKLOW : dword
msg db "Stack Overflow!", 0dh, 0ah, 0
enddata
xinit _init_stk,DEF_PRIORITY
assume ds:DGROUP
defp _init_stk
ret ; return
endproc _init_stk
xdefp __CHK
defpe __CHK ; new style stack check
xchg eax,4[esp] ; get parm in eax
call __STK ; call stack checker
mov eax,4[esp] ; restore eax
ret 4
endproc __CHK
xdefp __STK
defpe __STK
push eax ; save parm for __GRO routine
_guess ; guess: no overflow
cmp eax,esp ; - quit if user asking for too much
_quif ae ; - ...
sub eax,esp ; - calculate new low point
neg eax ; - calc what new SP would be
cmp eax,[_STACKLOW] ; - quit if too much
_quif be ; - ...
call __GRO ; - return
ret
_endguess ; endguess
__STKOVERFLOW:
xdefp "C",__STKOVERFLOW
pop eax ; pop the stack
ifdef __STACK__
push 1 ; ...
push offset msg ; print the error message
else
mov eax,offset msg ; print the error message
mov edx,1 ; ...
endif
call __fatal_runtime_error ; ...
endproc __STK
xdefp __GRO
defpe __GRO ; dummy function to resolve symbol
push eax ; save regs
push ebx ; ...
mov eax,12[esp] ; get size to grow by
mov ebx,-4 ; initialiaze index
lup: ; do {
mov [esp+ebx],ebx ; - touch that stack page
sub ebx,1000H ; - decrement by 4k
sub eax,1000H ; - decrement by 4k
jg lup ; } while stack left to go
pop ebx ; restore regs
pop eax ; ...
ret 4 ; return to caller
endproc __GRO
xdefp __alloca_probe
; on entry eax is size of stack to grow
; on exit esp has been advanced to new size
defpe __alloca_probe ; ms compatible function
push eax ; size parm to __GRO
call __GRO
push eax ; save size
lea eax,8[esp] ; get esp value to adjust
sub eax,[esp] ; carve off piece of stack
xchg eax,esp ; set new esp
mov eax,4[eax] ; snag return address
jmp eax ; return to caller
endproc __alloca_probe
endmod
end