tyler.durden/kernel
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This commit is contained in:
Kenneth J Davis 2024-08-05 09:41:13 -04:00
parent db43a4b343
commit b9440c7e0e
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GPG Key ID: 59D5F216C38F11FD
1 changed files with 30 additions and 8 deletions

38
kernel/kernel.asm

@ -848,16 +848,23 @@ int24_esbp times 2 dw 0 ;260 - pointer to criticalerr DPB
global _user_r, int21regs_off, int21regs_seg
_user_r:
int21regs_off dw 0 ;264 - pointer to int21h stack frame
int21regs_seg dw 0
int21regs_seg dw 0 ; i.e. points stack frame (SS:SP) with user registers when int21h called
global critical_sp
critical_sp dw 0 ;268 - critical error internal stack
critical_sp dw 0 ;268 - critical error internal stack, store SP during int24h
global current_ddsc
current_ddsc times 2 dw 0
current_ddsc times 2 dw 0 ;26A - pointer to DPB for ???
diskbuf_seg dw 0 ;26E - segment of disk buffer
dd 0 ;270 - saving partial cluster number??? - see https://faydoc.tripod.com/structures/16/1690.htm
dw 0
dw 0 ;276 - temp word
db 0 ;278 - media id returned by AH=1Bh,1Ch
db 0 ;279 - unused
; Pad to 059ah
times (27ah - ($ - _internal_data)) db 0
global current_device
current_device times 2 dw 0 ;27A - 0??
current_device times 2 dw 0 ;27A - point to device header if filename is character device
global _lpCurSft
_lpCurSft times 2 dw 0 ;27e - Current SFT
global _current_ldt
@ -867,11 +874,14 @@ _sda_lpFcb times 2 dw 0 ;286 - pointer to callers FCB
global _current_sft_idx
_current_sft_idx dw 0 ;28A - SFT index for next open
; used by MS NET
dw 0 ;28C - temp file handler
dd 0 ;28E - pointer to JFT entry (for file being opened) in process handle table
; Pad to 05b2h
times (292h - ($ - _internal_data)) db 0
dw __PriPathBuffer ; 292 - "sda_WFP_START" offset in DOS DS of first filename argument
dw __SecPathBuffer ; 294 - "sda_REN_WFP" offset in DOS DS of second filename argument
dw ffffh ; 296 - 0xffff or offset of last component in filename
; Pad to 05ceh
times (2aeh - ($ - _internal_data)) db 0
@ -884,15 +894,15 @@ _current_filepos times 2 dw 0 ;2AE - current offset in file
;global _save_DS
save_BX dw 0 ;2CA - unused by FreeDOS, for Win3.x
save_DS dw 0 ; compatibility, match MS's positions
dw 0
dw 0 ; store DS,BX on entry to int21h (ie caller's values)
global _prev_user_r
global prev_int21regs_off
global prev_int21regs_seg
_prev_user_r:
prev_int21regs_off dw 0 ;2D0 - pointer to prev int 21 frame
prev_int21regs_off dw 0 ;2D0 - pointer to prev int 21 frame (see offset 264h)
prev_int21regs_seg dw 0
; Pad to 05fdh
; Pad to 05fdh, 2D4 through 2E4 used for int21h/ax=6C00h
times (2ddh - ($ - _internal_data)) db 0
global _ext_open_action
global _ext_open_attrib
@ -900,6 +910,7 @@ prev_int21regs_seg dw 0
_ext_open_action dw 0 ;2DD - extended open action
_ext_open_attrib dw 0 ;2DF - extended open attrib
_ext_open_mode dw 0 ;2E1 - extended open mode
open_filename dd 0 ;2E3 pointer to filename to open (see ax=6C00h)
; Pad to 0620h
times (300h - ($ - _internal_data)) db 0
@ -916,6 +927,7 @@ _SearchDir_ren: times 32 db 0x90 ;315 - 32 byte dir entry for rename
; stacks are made to initialize to no-ops so that high-water
; testing can be performed
times STACK_SIZE*2-($-apistk_bottom) db 0x90
; critical error stack 331 bytes?, disk stack 384 bytes, character i/o 384 bytes
;300 - Error Processing Stack
global _error_tos
_error_tos:
@ -926,13 +938,23 @@ _disk_api_tos:
global _char_api_tos
_char_api_tos:
apistk_top:
db 0 ; 780 ???
db 0 ;780 device driver look-ahead (printer), see ah=64h
_VolChange db 0 ;781 - volume change
_VirtOpen db 0 ;782 - virtual open flag
; 783h to 788h are fastseek drive, 1st cluster, logical cluster, returned logical cluster
; 78Ah dw ? temp location of SYSINIT
; controlled variables end at offset 78Ch so pad to end
times (78ch - ($ - _internal_data)) db 0
; MSDOS 7.1+ with FAT32 SDA extended
;78Ch - 47 bytes of ???
times (7bbh - ($ - _internal_data)) db 0
absrdwrflg db 0 ;7bbh - 0=int 25h/26h absolute read/write, 1=int 21h/ax=7305h
times 12 dw 0 ;7bch to 7d2h, high word of 32bit values, see offsets 0x 2a2, 29c, 2bc, 29a, 276, 244, & registers ebx,edx,edi,ecx
times 3 dw 0 ; ???
;
; end of controlled variables
;