Contributor: JON JASIUNAS
{
From: JON JASIUNAS
Subj: Share Multi-tasking
}
{**************************
* SHARE.PAS v1.0 *
* *
* General purpose file *
* sharing routines *
**************************
1992-93 HyperDrive Software
Released into the public domain.}
{$S-,R-,D-}
{$IFOPT O+}
{$F+}
{$ENDIF}
unit Share;
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interface
{/////////////////////////////////////////////////////////////////////////////}
const
MaxLockRetries : Byte = 10;
NormalMode = 02ドル; { ---- 0010 }
ReadOnly = 00ドル; { ---- 0000 }
WriteOnly = 01ドル; { ---- 0001 }
ReadWrite = 02ドル; { ---- 0010 }
DenyAll = 10ドル; { 0001 ---- }
DenyWrite = 20ドル; { 0010 ---- }
DenyRead = 30ドル; { 0011 ---- }
DenyNone = 40ドル; { 0100 ---- }
NoInherit = 70ドル; { 1000 ---- }
type
Taskers = (NoTasker, DesqView, DoubleDOS, Windows, OS2, NetWare);
var
MultiTasking: Boolean;
MultiTasker : Taskers;
VideoSeg : Word;
VideoOfs : Word;
procedure SetFileMode(Mode: Word);
{- Set filemode for typed/untyped files }
procedure ResetFileMode;
{- Reset filemode to ReadWrite (02h) }
procedure LockFile(var F);
{- Lock file F }
procedure UnLockFile(var F);
{- Unlock file F }
procedure LockBytes(var F; Start, Bytes: LongInt);
{- Lock Bytes bytes of file F, starting with Start }
procedure UnLockBytes(var F; Start, Bytes: LongInt);
{- Unlock Bytes bytes of file F, starting with Start }
procedure LockRecords(var F; Start, Records: LongInt);
{- Lock Records records of file F, starting with Start }
procedure UnLockRecords(var F; Start, Records: LongInt);
{- Unlock Records records of file F, starting with Start }
function TimeOut: Boolean;
{- Check for LockRetry timeout }
procedure TimeOutReset;
{- Reset internal LockRetry counter }
function InDos: Boolean;
{- Is DOS busy? }
procedure GiveTimeSlice;
{- Give up remaining CPU time slice }
procedure BeginCrit;
{- Enter critical region }
procedure EndCrit;
{- End critical region }
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implementation
{/////////////////////////////////////////////////////////////////////////////}
uses
Dos;
var
InDosFlag: ^Word;
LockRetry: Byte;
{=============================================================================}
procedure FLock(Handle: Word; Pos, Len: LongInt);
Inline(
$B8/00ドル/5ドルC/ { mov AX,5ドルC00 ;DOS FLOCK, Lock subfunction}
8ドルB/5ドルE/04ドル/ { mov BX,[BP + 04] ;Place file handle in Bx register}
$C4/56ドル/06ドル/ { les DX,[BP + 06] ;Load position in ES:DX}
8ドルC/$C1/ { mov CX,ES ;Move ES pointer to CX register}
$C4/7ドルE/08ドル/ { les DI,[BP + 08] ;Load length in ES:DI}
8ドルC/$C6/ { mov SI,ES ;Move ES pointer to SI register}
$CD/21ドル); { int 21ドル ;Call DOS}
{-----------------------------------------------------------------------------}
procedure FUnlock(Handle: Word; Pos, Len: LongInt);
Inline(
$B8/01ドル/5ドルC/ { mov AX,5ドルC01 ;DOS FLOCK, Unlock subfunction}
8ドルB/5ドルE/04ドル/ { mov BX,[BP + 04] ;Place file handle in Bx register}
$C4/56ドル/06ドル/ { les DX,[BP + 06] ;Load position in ES:DX}
8ドルC/$C1/ { mov CX,ES ;Move ES pointer to CX register}
$C4/7ドルE/08ドル/ { les DI,[BP + 08] ;Load length in ES:DI}
8ドルC/$C6/ { mov SI,ES ;Move ES pointer to SI register}
$CD/21ドル); { int 21ドル ;Call DOS}
{=============================================================================}
procedure SetFileMode(Mode: Word);
begin
FileMode := Mode;
end; { SetFileMode }
{-----------------------------------------------------------------------------}
procedure ResetFileMode;
begin
FileMode := NormalMode;
end; { ResetFileMode }
{-----------------------------------------------------------------------------}
procedure LockFile(var F);
begin
If not MultiTasking then
Exit;
While InDos do
GiveTimeSlice;
FLock(FileRec(F).Handle, 0, FileSize(File(F)));
end; { LockFile }
{-----------------------------------------------------------------------------}
procedure UnLockFile(var F);
begin
If not MultiTasking then
Exit;
While InDos do
GiveTimeSlice;
FLock(FileRec(F).Handle, 0, FileSize(File(F)));
end; { UnLockFile }
{-----------------------------------------------------------------------------}
procedure LockBytes(var F; Start, Bytes: LongInt);
begin
If not MultiTasking then
Exit;
While InDos do
GiveTimeSlice;
FLock(FileRec(F).Handle, Start, Bytes);
end; { LockBytes }
{-----------------------------------------------------------------------------}
procedure UnLockBytes(var F; Start, Bytes: LongInt);
begin
If not MultiTasking then
Exit;
While InDos do
GiveTimeSlice;
FLock(FileRec(F).Handle, Start, Bytes);
end; { UnLockBytes }
{-----------------------------------------------------------------------------}
procedure LockRecords(var F; Start, Records: LongInt);
begin
If not MultiTasking then
Exit;
While InDos do
GiveTimeSlice;
FLock(FileRec(F).Handle, Start * FileRec(F).RecSize, Records * FileRec(F).Rec
end; { LockBytes }
{-----------------------------------------------------------------------------}
procedure UnLockRecords(var F; Start, Records: LongInt);
begin
If not MultiTasking then
Exit;
While InDos do
GiveTimeSlice;
FLock(FileRec(F).Handle, Start * FileRec(F).RecSize, Records * FileRec(F).Rec
end; { UnLockBytes }
{-----------------------------------------------------------------------------}
function TimeOut: Boolean;
begin
GiveTimeSlice;
TimeOut := True;
If MultiTasking and (LockRetry < MaxLockRetries) then begin TimeOut := False; Inc(LockRetry); end; { If } end; { TimeOut } {-----------------------------------------------------------------------------} procedure TimeOutReset; begin LockRetry := 0; end; { TimeOutReset } {-----------------------------------------------------------------------------} function InDos: Boolean; begin { InDos } InDos := InDosFlag^> 0;
end; { InDos }
{-----------------------------------------------------------------------------}
procedure GiveTimeSlice; ASSEMBLER;
asm { GiveTimeSlice }
cmp MultiTasker, DesqView
je @DVwait
cmp MultiTasker, DoubleDOS
je @DoubleDOSwait
cmp MultiTasker, Windows
je @WinOS2wait
cmp MultiTasker, OS2
je @WinOS2wait
cmp MultiTasker, NetWare
je @Netwarewait
@Doswait:
int 28ドル
jmp @WaitDone
@DVwait:
mov AX,1000ドル
int 15ドル
jmp @WaitDone
@DoubleDOSwait:
mov AX,$EE01
int 21ドル
jmp @WaitDone
@WinOS2wait:
mov AX,1680ドル
int 2ドルF
jmp @WaitDone
@Netwarewait:
mov BX,000ドルA
int 7ドルA
jmp @WaitDone
@WaitDone:
end; { TimeSlice }
{----------------------------------------------------------------------------}
procedure BeginCrit; ASSEMBLER;
asm { BeginCrit }
cmp MultiTasker, DesqView
je @DVCrit
cmp MultiTasker, DoubleDOS
je @DoubleDOSCrit
cmp MultiTasker, Windows
je @WinCrit
jmp @EndCrit
@DVCrit:
mov AX,101ドルB
int 15ドル
jmp @EndCrit
@DoubleDOSCrit:
mov AX,$EA00
int 21ドル
jmp @EndCrit
@WinCrit:
mov AX,1681ドル
int 2ドルF
jmp @EndCrit
@EndCrit:
end; { BeginCrit }
{----------------------------------------------------------------------------}
procedure EndCrit; ASSEMBLER;
asm { EndCrit }
cmp MultiTasker, DesqView
je @DVCrit
cmp MultiTasker, DoubleDOS
je @DoubleDOSCrit
cmp MultiTasker, Windows
je @WinCrit
jmp @EndCrit
@DVCrit:
mov AX,101ドルC
int 15ドル
jmp @EndCrit
@DoubleDOSCrit:
mov AX,$EB00
int 21ドル
jmp @EndCrit
@WinCrit:
mov AX,1682ドル
int 2ドルF
jmp @EndCrit
@EndCrit:
end; { EndCrit }
{============================================================================}
begin { Share }
{- Init }
LockRetry:= 0;
asm
@CheckDV:
mov AX, 2ドルB01
mov CX, 4445ドル
mov DX, 5351ドル
int 21ドル
cmp AL, $FF
je @CheckDoubleDOS
mov MultiTasker, DesqView
jmp @CheckDone
@CheckDoubleDOS:
mov AX, $E400
int 21ドル
cmp AL, 00ドル
je @CheckWindows
mov MultiTasker, DoubleDOS
jmp @CheckDone
@CheckWindows:
mov AX, 1600ドル
int 2ドルF
cmp AL, 00ドル
je @CheckOS2
cmp AL, 80ドル
je @CheckOS2
mov MultiTasker, Windows
jmp @CheckDone
@CheckOS2:
mov AX, 3001ドル
int 21ドル
cmp AL, 0ドルA
je @InOS2
cmp AL, 14ドル
jne @CheckNetware
@InOS2:
mov MultiTasker, OS2
jmp @CheckDone
@CheckNetware:
mov AX,7ドルA00
int 2ドルF
cmp AL,$FF
jne @NoTasker
mov MultiTasker, NetWare
jmp @CheckDone
@NoTasker:
mov MultiTasker, NoTasker
@CheckDone:
{-Set MultiTasking }
cmp MultiTasker, NoTasker
mov VideoSeg, $B800
mov VideoOfs, 0000ドル
je @NoMultiTasker
mov MultiTasking, 01ドル
{-Get video address }
mov AH, $FE
les DI, [$B8000000]
int 10ドル
mov VideoSeg, ES
mov VideoOfs, DI
jmp @Done
@NoMultiTasker:
mov MultiTasking, 00ドル
@Done:
{-Get InDos flag }
mov AH, 34ドル
int 21ドル
mov WORD PTR InDosFlag, BX
mov WORD PTR InDosFlag + 2, ES
end; { asm }
end. { Share }