Category : Modula II Source Code
Archive   : FIOASM.ZIP
Filename : FIOASM.A

module FioAsm

(*
File input-output routines for JPI Modula-2
by Carl Neiburger
169 N. 25th St.
San Jose, Calif. 95116

CompuServe No. 72336,2257

These routines are intended to replace low-level routines in JPI's FIO.MOD.
FioAsm's routines are optimized through assembly language.
*)

segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

public @path: org 65

public @ToPath: (* on entry, ds:si are string to copy *)
push es; push di (* and cx is length *)
cmp cx, 64 (* is string too long? *)
jb ToPath1
mov cx, 64 (* then truncate *)
ToPath1:
push cs
pop es
mov di,@path
xor al,al (* search for 0 *)
repne
movsb (* move it *)
push cs
pop ds
mov dx,@path
mov byte [di],0 (* add zero *)
ToPath2:
pop di; pop es
ret near 0

segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

public @IOR: dw 0

public @SetIorBool :
jnc SetOK
mov cs:[@IOR],ax
xor ax, ax
ret near 0
SetOK:
mov word cs:[@IOR],0
mov ax, 1
ret near 0

public FioAsm$IOresult:
mov ax, cs:[@IOR]
mov word cs:[@IOR],0
ret far 0

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @IOR
extrn @ToPath

public FioAsm$Create : CrNamLen = 10; CrNamSeg = 8; CrNamOfs = 6;
push bp; mov bp,sp
push ds; push si
lds si, [bp][CrNamOfs]
mov cx, [bp][CrNamLen]
call near @ToPath
mov ah, 3CH (* create file *)
xor cx, cx (* no attribute *)
int 21H
jnc CrRet (* handle is in ax *)
mov cs:[@IOR],ax (* error is in ax *)
xor ax,ax
not ax (* return MAX(CARDINAL) *)
CrRet:
pop si; pop ds
pop bp; ret far 6

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @IOR
extrn @ToPath

public FioAsm$Open : OpNamLen = 12; OpNamSeg = 10; OpNamOfs = 8; OpType = 6;
push bp; mov bp,sp
push ds; push si
lds si, [bp][OpNamOfs]
mov cx, [bp][OpNamLen]
call near @ToPath
mov ah, 3DH (* open file *)
mov al, [bp][OpType]
int 21H
jnc OpRet (* handle is in ax *)
mov cs:[@IOR],ax (* error is in ax *)
xor ax,ax
not ax (* return MAX(CARDINAL) *)
OpRet:
pop si; pop ds
pop bp; ret far 8

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @SetIorBool

public FioAsm$Close : ClFile = 6;
push bp; mov bp,sp
mov bx, [bp][ClFile]
mov ah, 3EH (* close file *)
int 21H
call near @SetIorBool
pop bp; ret far 2

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @SetIorBool

public FioAsm$Truncate : TrFile = 6;
push bp; mov bp,sp
mov bx, [bp][TrFile]
mov ah, 40H (* write *)
xor cx, cx
int 21H
call near @SetIorBool
pop bp; ret far 2

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @IOR

public FioAsm$Read : ReFile = 14; ReBufLen = 12;
ReBufSeg = 10; ReBufOfs = 8; ReCount = 6;
push bp; mov bp,sp
push ds;
lds dx, [bp][ReBufOfs]
mov cx, [bp][ReCount]
mov bx, [bp][ReFile]
mov ah, 3FH (* read file *)
int 21H
jnc ReRet (* bytes read are ax *)
mov cs:[@IOR],ax (* error is in ax *)
xor ax,ax (* if error, return zero *)
ReRet:
pop ds
pop bp; ret far 10

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @IOR

public FioAsm$Write : WrFile = 14; WrBufLen = 12;
WrBufSeg = 10; WrBufOfs = 8; WrCount = 6;
push bp; mov bp,sp
push ds;
lds dx, [bp][WrBufOfs]
mov cx, [bp][WrCount]
mov bx, [bp][WrFile]
mov ah, 40H (* write file *)
int 21H
jnc WrRet (* bytes written are in ax *)
mov cs:[@IOR],ax (* error is in ax *)
xor ax,ax (* if error, return zero *)
WrRet:
pop ds
pop bp; ret far 10

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @SetIorBool
extrn @ToPath

public FioAsm$Rename : OldLen = 16; OldSeg = 14; OldOfs = 12;
NewLen = 10; NewSeg = 8; NewOfs = 6;
push bp; mov bp,sp
push ds; push si; push es; push di;
lds si,[bp][NewOfs]
mov cx,[bp][NewLen]
xor ax, ax
push ax (* zero to terminate string *)
sub sp,cx (* make room for string *)
push ss
pop es
mov di,sp
rep
movsb (* move it *)
mov di,sp (* point back to string start *)
lds si, [bp][OldOfs]
mov cx, [bp][OldLen]
call near @ToPath (* point ds:dx to old name *)
mov ah, 56H (* rename *)
int 21H
add sp,[bp][NewLen] (* restore stack pointer *)
pop si (* and zero at end *)
call near @SetIorBool
pop di; pop es; pop si; pop ds
pop bp; ret far 12

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

public FioAsm$GetDrive:
mov ah, 19H (* get drive *)
int 21H
inc al (* bump A up to 1, etc *)
ret far 0

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn FioAsm$GetDrive

public FioAsm$Drives:
call far FioAsm$GetDrive
dec al (* A = 0 in this case *)
mov dl, al
mov ah, 0EH (* number of drives *)
int 21H
ret far 0

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn FioAsm$Drives
extrn @SetIorBool

public FioAsm$SetDrive:
push bp; mov bp,sp
call far FioAsm$Drives (* how many are there? *)
mov dl, [bp][6]
cmp al,dl (* does requested drive exist? *)
jl SDerr (* if so, forget it *)
mov ah, 0EH (* set drive *)
dec dl
int 21H
clc
jmp SDret
SDerr:
mov ax,15
stc
SDret:
call near @SetIorBool
pop bp
ret far 2

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

public FioAsm$SetVerify: SVon = 6
push bp; mov bp,sp
xor dl, dl
mov al, [bp][SVon]
mov ah, 2EH (* number of drives *)
int 21H
pop bp
ret far 2

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

public FioAsm$VerifyIsOn:
mov ah, 54H (* number of drives *)
int 21H
ret far 0

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @SetIorBool
extrn @ToPath

public FioAsm$SetFileAttribute : Attr = 12; FNLen = 10; FNSeg = 8; FNOfs = 6;
push bp; mov bp,sp
push ds; push si
lds si, [bp][FNOfs]
mov cx, [bp][FNLen]
call near @ToPath
mov cx, [bp][Attr]
mov ax, 4301H
int 21H
call near @SetIorBool
pop si; pop ds
pop bp; ret far 8

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @IOR
extrn @ToPath

public FioAsm$GetFileAttribute : FNLen = 10; FNSeg = 8; FNOfs = 6;
push bp; mov bp,sp
push ds; push si
lds si, [bp][FNOfs]
mov cx, [bp][FNLen]
call near @ToPath
mov ax, 4300H
int 21H
jnc GAtOK
mov cs:[@IOR],ax (* error is in ax *)
mov ax, 40H (* attribute = ioerror *)
jmp GAtRet
GAtOK:
mov ax, cx (* return attributes *)
GAtRet:
pop si; pop ds
pop bp; ret far 6

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @IOR

public FioAsm$FileTime : Fi = 6;
push bp; mov bp,sp
mov bx, [bp][Fi]
mov ax, 5700H
int 21H
jnc TimeOK
xor ax, ax (* we goofed; no time *)
xor dx, dx

mov cs:[@IOR],ax (* error is in ax *)
jmp TimeRet
TimeOK:
mov ax, cx (* return low byte in ax; high is in dx already *)
TimeRet:
pop bp; ret far 2

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @SetIorBool

public FioAsm$SetFileTime : Fi = 10; HiTime = 8; LoTime = 6;
push bp; mov bp,sp
mov ax, 5701H
mov bx, [bp][Fi]
mov cx, [bp][LoTime]
mov dx, [bp][HiTime]
int 21H
call near @SetIorBool
pop bp; ret far 6

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

public FioAsm$DecodeFileTime : PackedDate = 12; PackedTime = 10;
DTSeg = 8; DTOfs = 6;
DYear = 0; DMonth = 2; DDay = 4; DHours = 6; DMins = 8; DSecs = 10;
push bp; mov bp,sp
push ds; push di
lds di, [bp][DTOfs]
mov ax, [bp][PackedDate]
push ax
and ax, 1FH
mov [di][DDay], ax
pop ax
mov cx, 5
shr ax, cx
push ax
and ax, 0FH
mov [di][DMonth], ax
pop ax
mov cx, 4
shr ax, cx
add ax, 1980
mov [di][DYear], ax

mov ax, [bp][PackedTime]
push ax
and ax, 1FH
shl ax, 1
mov [di][DSecs], ax
pop ax
mov cx, 5
shr ax, cx
push ax
and ax, 3FH
mov [di][DMins], ax
pop ax
mov cx, 6
shr ax, cx
mov [di][DHours], ax
pop di; pop ds
pop bp; ret far 8

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

public FioAsm$EncodeFileTime :
Year = 6; Month = 8; Day = 10; Hours = 12; Mins = 14; Secs = 16;
push bp; mov bp,sp
mov ax, [bp][Year]
sub ax, 1980
mov cx, 4
shl ax, cx
add al, [bp][Month]
mov cx, 5
shl ax, cx
add al, [bp][Day]
mov dx, ax
mov ax, [bp][Hours]
mov cx, 6
shl ax, cx
add al, [bp][Mins]
mov cx, 5
shl ax, cx
mov bx, ax
mov ax, [bp][Secs]
shr ax, 1
add ax, bx
pop bp; ret far 12

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

public FioAsm$GetDir : GDrive = 12; GDLen = 10; GDSeg = 8; GDOfs = 6;
push bp; mov bp,sp
push ds; push si;
lds si, [bp][GDOfs]
mov dl, [bp][GDrive]
mov ah, 47H (* getdir *)
int 21H
jnc GDRet
mov byte [si], 0 (* set string = 0C *)
GDRet:
pop si; pop ds
pop bp; ret far 8

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @SetIorBool
extrn @ToPath

public FioAsm$Erase :
mov ah, 41H (* erase file *)
jmp Act

public FioAsm$RmDir :
mov ah, 3AH (* rmDir *)
jmp Act

public FioAsm$MkDir :
mov ah, 39H (* mkDir *)
jmp Act

public FioAsm$ChDir :
mov ah, 3BH (* chDir *)

Act: ActLen = 10; ActNamSeg = 8; ActNamOfs = 6;
push bp; mov bp,sp
push ds; push si
lds si, [bp][ActNamOfs]
mov cx, [bp][ActLen]
call near @ToPath
int 21H
call near @SetIorBool
pop si; pop ds
pop bp; ret far 6

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @IOR

public FioAsm$Seek : SeekFile = 14; SeekHi = 12; SeekLo = 10;
SeekOKSeg = 8; SeekOKOfs = 6
push bp; mov bp,sp
push ds; push di;
lds di, [bp][SeekOKOfs]
mov dx, [bp][SeekLo]
mov cx, [bp][SeekHi]
mov bx, [bp][SeekFile]
mov ax, 4200H (* seek absolute *)
int 21H
jnc SeekGood
mov cs:[@IOR],ax (* error is in ax *)
mov byte [di],0 (* OK false *)
jmp SeekRet
SeekGood:
mov byte [di],1
SeekRet:
pop di; pop ds
pop bp; ret far 10

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @IOR

public FioAsm$SeekRel : SeekFile = 14; SeekHi = 12; SeekLo = 10;
SeekOKSeg = 8; SeekOKOfs = 6
push bp; mov bp,sp
push ds; push di;
lds di, [bp][SeekOKOfs]
mov dx, [bp][SeekLo]
mov cx, [bp][SeekHi]
mov bx, [bp][SeekFile]
mov ax, 4201H (* seek relativee *)
int 21H
jnc SeekRelGood
mov cs:[@IOR],ax (* error is in ax *)
mov byte [di],0 (* OK false *)
jmp SeekRelRet
SeekRelGood:
mov byte [di],1
SeekRelRet:
pop di; pop ds
pop bp; ret far 10

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @IOR

public FioAsm$GetPos : GetFile = 10; GetOKSeg = 8; GetOKOfs = 6
push bp; mov bp,sp
push ds; push di;
lds di, [bp][GetOKOfs]
xor dx,dx (* no offset *)
xor cx,cx
mov bx, [bp][GetFile]
mov ax, 4201H (* seek relative *)
int 21H
jnc GetGood
mov cs:[@IOR],ax (* error is in ax *)
mov byte [di],0 (* OK false *)
jmp GetRet
GetGood:
mov byte [di],1
GetRet:
pop di; pop ds
pop bp; ret far 6

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @IOR

public FioAsm$SeekEOF : SEOFFile = 10; SEOFokSeg = 8; SEOFokOfs = 6
push bp; mov bp,sp
push ds; push di;
lds di, [bp][SEOFokOfs]
xor dx,dx
xor cx,cx
mov bx, [bp][SEOFFile]
mov ax, 4202H (* seek EOF *)
int 21H
jnc SEOFgood
mov cs:[@IOR],ax (* error is in ax *)
mov byte [di],0 (* OK false *)
jmp SEOFRet
SEOFgood:
mov byte [di],1
SEOFRet:
pop di; pop ds
pop bp; ret far 6

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @IOR

public FioAsm$EOF : EOFFile = 10; EOFokSeg = 8; EOFokOfs = 6
push bp; mov bp,sp
push ds; push di;
lds di, [bp][EOFokOfs]
mov bx, [bp][EOFFile]
mov ax, 4406H (* device status, input *)
int 21H
jnc EOFgood
mov cs:[@IOR],ax (* error is in ax *)
mov ax,1 (* set TRUE, just in case *)
mov byte ds:[di],0 (* OK false *)
jmp EofRet
EOFgood:
not al (* reverse TRUE, FALSE *)
and ax,1 (* reset all but last bit *)
mov byte ds:[di],1 (* OK true *)
EofRet:
pop di; pop ds;
pop bp; ret far 6

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

extrn @ToPath

public FioAsm$ReadFirstEntry : R1Len = 16; R1Seg = 14; R1Ofs = 12;
R1Attr = 10; D1Seg = 8; D1Ofs = 6;
push bp; mov bp,sp
push ds; push es; push di; push si
lds dx, [bp][D1Ofs]
mov ah, 1AH (* set DTA to D *)
int 21H
mov cx,[bp][R1Len] (* get buffer length *)
lds si,[bp][R1Ofs]
call near @ToPath
mov ah, 4EH (* read first *)
mov cx, [bp][R1Attr]
int 21H
jnc R1OK
xor ax,ax (* false *)
jmp R1Ret
R1OK:
mov ax, 1
R1Ret:
pop si; pop di; pop es; pop ds
pop bp; ret far 12

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

public FioAsm$ReadNextEntry : D2Seg = 8; D2Ofs = 6;
push bp; mov bp,sp
push ds;
lds dx, [bp][D2Ofs]
mov ah, 1AH (* set DTA to D *)
int 21H
mov ah, 4FH (* read next *)
int 21H
jnc R2OK
xor ax,ax (* false *)
jmp R2Ret
R2OK:
mov ax, 1
R2Ret:
pop ds
pop bp; ret far 4

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

public FioAsm$SetDTA: DTASeg = 8; DTAOfs = 6;
push bp; mov bp,sp
push ds;
lds dx, [bp][DTAOfs]
mov ah, 1AH (* set DTA to D *)
int 21H
pop ds
pop bp; ret far 4

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

public FioAsm$GetDTA:
push bp; mov bp,sp
push ds; push es
mov ah, 2FH
int 21H
mov dx,es
mov ax, bx
pop es; pop ds
pop bp; ret far 0

section ; segment C_CODE(CODE,28H); group G_CODE(C_CODE); select C_CODE

public FioAsm$DiskFree: dr = 10; BPCseg = 8; BPCofs = 6;
push bp; mov bp,sp
push ds; push si;
lds si,[bp][BPCofs]
mov dl, [bp][dr] (* load drive *)
mov ah, 36H (* get disk data *)
int 21H
cmp ax, 0FFFFH
jne OKdr
xor ax, ax
OKdr:
mul cx
mov [si],ax
mul bx
pop si; pop ds
pop bp; ret far 6

end