
<<PlayNoiseImpl.mesa>>
<<Last Edited by: Swinehart, April 28, 1986 2:11:48 pm PDT>>
<<>>
DIRECTORY
Atom USING [ GetProp, MakeAtom, PutProp ],
Booting USING [ CallBootingProcs, Deregister, RegisterProcs, CheckpointProc ],
Commander USING [ CommandProc, Register ],
FinchSmarts USING [ PlayNoise ],
Process USING [ Detach, MsecToTicks, Pause ],
UserProfile USING [ Token ]
;

PlayNoiseImpl: CEDAR PROGRAM 
IMPORTS
Atom, Booting, Commander, FinchSmarts, Process, UserProfile
= {

reallyBoot: BOOL_TRUE;
didOurBest: BOOL;
maxTime: CARDINAL _ 4000;

PlayTheRollbackButton: Booting.CheckpointProc = TRUSTED {
PlayAButton[$rollback];
IF ~reallyBoot THEN rejection _ "Just pretending";
};

PlayAButton: PROC[name: ATOM] = TRUSTED {
didOurBest _ FALSE;
Process.Detach[FORK ReallyPlayAButton[name]];
FOR i: NAT IN [0..100) DO
Process.Pause[Process.MsecToTicks[maxTime/100]];
IF didOurBest THEN EXIT;
ENDLOOP;
};

ReallyPlayAButton: PROC[name: ATOM] = {
[]_FinchSmarts.PlayNoise[noiseName: name, wait: TRUE];
didOurBest _ TRUE;
};

    Register: PROC [newPlayTheRollbackButton: Booting.CheckpointProc] ~ {
        vo: REF=Atom.GetProp[$Interfaces, $PlayTheRollback];
        oldPlayTheRollbackButton: REF Booting.CheckpointProc _
            NARROW[vo, REF Booting.CheckpointProc];
        IF oldPlayTheRollbackButton # NIL THEN
            Booting.Deregister[c: oldPlayTheRollbackButton^, r: NIL, b: oldPlayTheRollbackButton^];
        IF newPlayTheRollbackButton = NIL THEN RETURN;
        Booting.RegisterProcs[c: PlayTheRollbackButton, r: NIL, b: PlayTheRollbackButton];
        Atom.PutProp[$Interfaces, $PlayTheRollback, NEW[Booting.CheckpointProc_PlayTheRollbackButton]];
        };

    DoNoisyBoot: Commander.CommandProc = {
        Register[PlayTheRollbackButton];
        };

    NoNoisyBoot: Commander.CommandProc = {
        Register[NIL];
        };

    TestNoisyBoot: Commander.CommandProc = {
        []_Booting.CallBootingProcs[];
        };

IF Atom.MakeAtom[UserProfile.Token["Finch.NoisyBoot", "FALSE"]] = $TRUE
THEN Register[PlayTheRollbackButton];
Commander.Register["NoisyBoot", DoNoisyBoot, "Pleasant surprise on rollback or boot"];
Commander.Register["TestNoisyBoot", TestNoisyBoot];
Commander.Register["NoNoisyBoot", NoNoisyBoot, "No pleasant surprise on rollback or boot"];
}.