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Line 17... |
| 17 |
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17 |
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| 18 |
; offset
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18 |
; offset
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| 19 |
SIG1 dw 0x1983 ; +0
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19 |
SIG1 dw 0x1983 ; +0
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| 20 |
SIG2 dw 0x1985 ; +2
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20 |
SIG2 dw 0x1985 ; +2
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| 21 |
SIG3 dw 0x2017 ; +4
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21 |
SIG3 dw 0x2017 ; +4
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| 22 |
SIG4 dw 0x2019 ; +6 this acts also as a guardval to detect stack overflows
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22 |
SIG4 dw 0x2019 ; +6 acts also as a guardval to detect severe stack overflows
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23 |
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24 |
; Buffer used to remember previous command, when SvarCOM calls the buffered
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25 |
; input service at INT 21h,AH=0x0A.
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26 |
; This buffer is right before the stack, so in case of a stack overflow event
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27 |
; (for example because of a "too ambitious" TSR) only this buffer is damaged,
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28 |
; and can be invalidated without much harm.
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29 |
INPUTBUF: times 130 db 0
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30 |
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31 |
; This stack sig is a guardian value that is checked by the transient part of
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32 |
; SvarCOM to detect possible stack overflows. If a stack overflow occurs, then
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33 |
; the INPUTBUFF area above is invalidated and stack signature reverted.
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34 |
STACKSIG dw 0xCAFE
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| 23 |
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35 |
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| 24 |
; DOS int 21h functions that I use require at least 40 bytes of stack under
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36 |
; DOS int 21h functions that I use require at least 40 bytes of stack under
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| 25 |
; DOS-C (FreeDOS) kernel, so here I reserve 64 bytes juste to be sure
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37 |
; DOS-C (FreeDOS) kernel, so here I reserve 64 bytes juste to be sure
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| 26 |
STACKBUF db "XXX SVARCOM RMOD BY MATEUSZ VISTE XXXXXXXXXXXXXXXXXXXXXXXXXXXX"
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38 |
STACKBUF db "XXX SVARCOM RMOD BY MATEUSZ VISTE XXXXXXXXXXXXXXXXXXXXXXXXXXXX"
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| 27 |
STACKPTR dw 0
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39 |
STACKPTR dw 0
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