RBBS in a Box Volume 1 #3.1/RBBSIABOX31.cdr/craz/commod.txt

Text File | 1985-03-16 | 7KB | 325 lines

a 1ed
;this file contains the code to modify command.com in several ways
; 1) increases command.com's size by 1k and intercepts the command processor
;               (see PC August 7,1984 "Get SET for Speed")
;
; 2) adds 4 Resident commands to command.com
;       these commands are:
;               i) a utility to switch from 80col. mono to 40
;                  col. color.  This command is invoked by
;                  type s <space> <return> at the Dos prompt.
;                  Note that there must be a space following
;                  the letter s.  After this command is entered
;                  the active screen will change over to the unactive
;                  one.
;
;              ii) a modified file deletion routine similar to
;                  VDEL.COM.  The command is invoked by typing
;                  d <space> drive id. (not neccessary) file
;                  deliminators <return> at the Dos prompt.
;                  For example d b:*.bas  Files which have the
;                  attribute Read Only will generate the error
;                  message 'Access Denied' and will not be deleted.
;
;             iii) a utility to change the attribute of files
;                  between Read/Write and Read Only, or Hidden
;                  and Unhidden, or System and Non-System.  The
;                  command is invoked by typing a <space> 'x' filespec
;                  at the Dos prompt.  The 'x' must be replaced by
;                  one of the following valid commands.
;                       c - current attributes of file
;                       r - toggle Read/Write / Read Only
;                       h - toggle Hidden/Unhidden
;                       s - toggle System/Non-System
;
;                  For example.  a c command.com
;                    will display the current attributes of command.com
;
;              iv) a utility to beep the speaker.  Invoked by typing
;                  b <space> <return>.  For use in batch files
;                  the b <space> must be followed by any character.
;                  This is to keep the <space> after the b from
;                  being truncated.
;
; ****  To add these commands to command.com type the following at the
;       Dos prompt
;                       DEBUG COMMAND.COM < COMMOD.TXT <return>
;
; At the current time I have not documented this modification.  If anyone
;has any questions drop me a message.  If anyone has any specs. on making
;this modification DOS 2.1 compatible please let me know!  This shouldn't
;be too hard - all that is required is the addresses for making command.com
;larger.
;
;NOTE: For anyone examining the code they will note that all references to
;data areas are smaller by hex 10C0.  This is not a bug - it is like this due
;the way command.com loads.
;
; Mike Cumming
; 94 Aldershot Blvd
; Wpg, Man.
; Compuserve 70376,466
;
add dx,3270  ; this set of code increases command.com's size

a 3ad
cmp bx,3b0

a 3cd
sub bx,390

a 691
mov cx,37be

a 6a9
cmp cx,37be

a c9d
sub ax,390

a 140b
call 4030

m 4030 4580 4430
f 4030 442f 0
r cx
4900
a 4030
MOV     SI,2B8B         ; This section of code intercepts the command
CLD                     ; processor and decides whether any action
LODSB                   ; should be taken
PUSH    AX
LODSB
CMP     AL,20
POP     AX
JNZ     405F
AND     AL,DF
CMP     AL,53
JZ      4077
CMP     AL,44
JZ      40A3
CMP     AL,41
JZ      4066
CMP     AL,42
JZ      4070
CMP     AL,FF
JZ      406D
CMP     AL,FF
JZ      4072
JMP     405E
MOV     DI,2B8B
MOV     AX,0D0D
STOSW
PUSH    CS
POP     ES
MOV     CX,0886
JMP     CX
JMP     4160
NOP
NOP
NOP
NOP
NOP
NOP
NOP
JMP     425E
NOP
NOP
NOP
NOP

a 4077
PUSH    DS              ; this section of code switches screens
MOV     AX,0040
MOV     DS,AX
MOV     AL,[0010]
PUSH    AX
AND     AL,30
CMP     AL,30
POP     AX
JZ      4094
OR      AL,30
MOV     [0010],AL
MOV     AX,0007
INT     10
JMP     40A0
AND     AL,CF
OR      AL,20
MOV     [0010],AL
MOV     AX,0001
INT     10
POP     DS
JMP     4058

a 40a3
MOV     DX,2C4F         ; this is the random delete code
MOV     AH,1A
INT     21
MOV     SI,2B8D
LODSB
CMP     AL,0D
JNZ     40AD
MOV     DI,SI
SUB     DI,01
MOV     AL,00
STOSB
MOV     DX,2B8D
MOV     AH,4E
INT     21
JB      40F1
MOV     DX,305B
MOV     AH,09
INT     21
MOV     SI,2C6D
LODSB
CMP     AL,00
JZ      40DA
MOV     DL,AL
MOV     AH,02
INT     21
JMP     40CD
MOV     DX,3066
MOV     AH,09
INT     21
MOV     AH,01
INT     21
AND     AL,DF
CMP     AL,59
JZ      40FB
MOV     AH,4F
INT     21
JMP     40C1
MOV     DX,3070
MOV     AH,09
INT     21
JMP     4058
MOV     SI,2C6D
MOV     DI,2B8F
LODSB
STOSB
CMP     AL,00
JNZ     4101
JMP     424E
MOV     AH,41
INT     21
JB      4112
JMP     40EB
MOV     AH,09
MOV     DX,308E
INT     21
JMP     40EB

a 4160
MOV     SI,2B8F         ; this code alters attribute bytes of files
LODSB
CMP     AL,0D
JNZ     4163
MOV     AL,00
MOV     [SI-01],AL
MOV     DX,2B8F
MOV     AH,43
INT     21
JB      41DE
MOV     AL,[2B8D]
AND     AL,DF
CMP     AL,43
JZ      419D
CMP     AL,52
JNZ     4187
XOR     CX,0001
CMP     AL,53
JNZ     418F
XOR     CX,0004
CMP     AL,48
JNZ     4197
XOR     CX,0002
MOV     AL,01
MOV     AH,43
INT     21
MOV     AH,09
MOV     BX,CX
AND     BX,00FE
CMP     BX,CX
JZ      41AE
MOV     DX,313E
JMP     41B1
MOV     DX,314B
INT     21
MOV     BX,CX
AND     BX,00FD
CMP     BX,CX
JZ      41C2
MOV     DX,315A
JMP     41C5
MOV     DX,3165
INT     21
MOV     BX,CX
AND     BX,00FB
CMP     BX,CX
JZ      41D6
MOV     DX,3172
JMP     41D9
MOV     DX,317E
INT     21
JMP     4058
MOV     DX,3128
MOV     AH,09
INT     21
JMP     4058

a 424e
MOV     DX,2B8D         ; these few lines are to fix a small bug that
MOV     AL,[2B8E]       ; was in the random delete.  It was placed here
CMP     AL,3A           ; because of the difficulty of moving all the
JZ      425B            ; code that was above it
MOV     DX,2B8F
JMP     410A

a 425e
MOV     BX,05DC         ; this code beeps the speaker
IN      AL,61
PUSH    AX
AND     AL,FC
OUT     61,AL
MOV     CX,0032
LOOP    426B
OR      AL,02
OUT     61,AL
MOV     CX,0032
LOOP    4274
DEC     BX
JNZ     4264
POP     AX
OUT     61,AL
JMP     4058

;the following data is for error messages etc.

e 411B
0D 0A 0A 44 65
e 4120
6C 65 74 65 20 24 20 28 79 2F 6E 29 20 3F 20 24
e 4130
0D 0A 0A 4E 6F 20 6D 6F 72 65 20 6D 61 74 63 68
e 4140
69 6E 67 20 66 69 6C 65 73 2E 0D 0A 0A 24 20 20
e 4150
07 41 63 63 65 73 73 20 44 65 6E 69 65 64 2E 24
e 41E8
0A 0A 0D 46 69 6C 65 20
e 41F0
6E 6F 74 20 66 6F 75 6E 64 0D 0A 0A 24 0D 0A 52
e 4200
65 61 64 20 4F 6E 6C 79 20 20 24 0D 0A 52 65 61
e 4210
64 2F 57 72 69 74 65 20 20 24 0D 0A 48 69 64 64
e 4220
65 6E 20 20 24 0D 0A 55 6E 48 69 64 64 65 6E 20
e 4230
20 24 0D 0A 53 79 73 74 65 6D 0D 0A 0A 24 0D 0A
e 4240
4E 6F 6E 2D 53 79 73 74 65 6D 0D 0A 0A 24

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