DIRECTORYBasics USING [LongNumber],Process USING [Detach],SafeStorage USING [CantEstablishFinalization, EnableFinalization, EstablishFinalization, FinalizationQueue, FQNext, NewFQ],YggDID USING [DID, EqualDIDs, HashDID],YggDIDMap USING [RunList],YggFile USING [FileHandle],YggFileInternal USING [FileHandleRep],YggInternal USING [FileHandle];YggFileTableImpl: CEDAR MONITORIMPORTS Process, SafeStorage, YggDIDEXPORTS YggInternal, YggFileInternal = {FileHandle: TYPE =  YggInternal.FileHandle;FileHandleRep: PUBLIC TYPE = YggFileInternal.FileHandleRep;HashValue: TYPE = [0..256);TableEntry: TYPE = LIST OF RECORD[fh: YggFile.FileHandle,reissued: BOOL _ FALSE];Table: TYPE = ARRAY HashValue OF TableEntry;table: REF Table = NEW[Table _ ALL[NIL]];lastInsert: CARD _ 0;lastRemove: CARD _ 0;contents: INT _ 0;debug: BOOL _ FALSE;Hash: PROC [did: YggDID.DID, fileUse: ATOM] RETURNS [HashValue] = TRUSTED {atomAddress: CARD32 = LOOPHOLE[fileUse];didHash: CARD32 = YggDID.HashDID[did];ah: Basics.LongNumber;dh: Basics.LongNumber;bh: CARD32;l: Basics.LongNumber;ah _ LOOPHOLE[atomAddress, Basics.LongNumber];dh _ LOOPHOLE[didHash, Basics.LongNumber];bh _ ah.hi + dh.lo;l _ [li[LOOPHOLE[bh]]];RETURN[l.ll];};CountContents: INTERNAL PROC RETURNS [total: INT _ 0] = {FOR h: HashValue IN HashValue DOFOR fileList: TableEntry _ table[h], fileList.rest UNTIL fileList = NIL DOtotal _ total+1;ENDLOOP;ENDLOOP;};CheckContents: INTERNAL PROC = {found: INT = CountContents[];IF found # contents THEN ERROR ConfusedHash[];};Lookup: PUBLIC ENTRY PROC [runList: YggDIDMap.RunList, did: YggDID.DID, fileUse: ATOM] RETURNS [file: YggFile.FileHandle] = {ENABLE UNWIND => NULL;fileList: TableEntry;h: HashValue = Hash[did, fileUse];FOR fileList _ table[h], fileList.rest UNTIL fileList = NIL DOIF YggDID.EqualDIDs[fileList.first.fh.did, did] AND fileList.first.fh.fileUse = fileUse THEN {fileList.first.reissued _ TRUE;file _ fileList.first.fh;EXIT;};REPEAT FINISHED => {file _ InternalCreate[];file.did _ did;file.fileUse _ fileUse;file.runList _ runList;FOR rl: YggDIDMap.RunList _ runList, rl.rest UNTIL rl = NIL DOfile.sizeInPages _ MAX [rl.first.firstPage+rl.first.pages, file.sizeInPages];ENDLOOP;InternalInsert[file];}ENDLOOP;};ConfusedHash: ERROR = CODE;allocNotInserted: INT _ 0;insertion: CONDITION;AllocForCreate: PUBLIC ENTRY PROC RETURNS [YggFile.FileHandle] = {ENABLE UNWIND => NULL;allocNotInserted _ allocNotInserted+1;RETURN[ InternalCreate[] ]};Insert: PUBLIC ENTRY PROC [new: YggFile.FileHandle] = {ENABLE UNWIND => NULL;allocNotInserted _ allocNotInserted-1; BROADCAST insertion;InternalInsert[new];};DontInsert: PUBLIC ENTRY PROC = {allocNotInserted _ allocNotInserted-1; BROADCAST insertion;};InternalInsert: INTERNAL PROC [new: YggFile.FileHandle] = {h: HashValue _ Hash[new.did, new.fileUse];prev: TableEntry _ NIL;fileList: TableEntry _ table[h];IF debug THEN CheckContents[];DOIF fileList = NIL THEN {  -- stick new at the end of this hash chainlastInsert _ LOOPHOLE[new, LONG CARDINAL];  -- for debuggingcontents _ contents+1;IF prev = NIL THEN table[h] _ LIST[[new, FALSE]] ELSE prev.rest _ CONS[[new, FALSE], NIL]--prev.rest = NIL--;  SafeStorage.EnableFinalization[new];EXIT};prev _ fileList;fileList _ fileList.rest;ENDLOOP;IF debug THEN CheckContents[];};MyQueue: SafeStorage.FinalizationQueue = SafeStorage.NewFQ[length: 50];Remove: INTERNAL PROC [old: YggFile.FileHandle] = {h: HashValue = Hash[old.did, old.fileUse];prev: TableEntry _ NIL;fileList: TableEntry _ table[h];IF debug THEN CheckContents[];DOIF fileList = NIL THEN EXIT --ERROR--;  -- old was not found in table.  IF fileList.first.fh = old THEN {contents _ contents-1;IF prev = NIL THEN table[h] _ fileList.rest ELSE prev.rest _ fileList.rest;EXIT};prev _ fileList;fileList _ fileList.rest;ENDLOOP;lastRemove _ LOOPHOLE[old, LONG CARDINAL];IF debug THEN CheckContents[];};DuplicateHashTableEntry: ERROR = CODE;InternalCreate: INTERNAL PROC RETURNS [YggFile.FileHandle] = {RETURN[NEW[YggFileInternal.FileHandleRep _ []]]};FileTableFinalizationProcess: PROC = {DOinnerFileTableFinalizationProcess: ENTRY PROC [] = {ENABLE UNWIND => NULL;fileList: TableEntry _ NIL;h: HashValue = Hash[file.did, file.fileUse];FOR fileList _ table[h], fileList.rest UNTIL fileList = NIL DOIF YggDID.EqualDIDs[fileList.first.fh.did, file.did] AND fileList.first.fh.fileUse = file.fileUse THEN {fileList.first.reissued _ TRUE;IF file # fileList.first.fh THEN ERROR;EXIT;};REPEAT FINISHED => {  -- not found!  OK while testing in PrincOps, but ERROR in PCedar};ENDLOOP;IF fileList # NIL THEN {IF fileList.first.reissued THEN {IF debug THEN {fh: TableEntry _ table[Hash[fileList.first.fh.did, fileList.first.fh.fileUse]];UNTIL fh = NIL DO IF fh = fileList THEN EXIT ELSE fh _ fh.rest ENDLOOP;};fileList.first.reissued _ FALSE;SafeStorage.EnableFinalization[fileList];} ELSE {Remove[fileList.first.fh];};};};file: REF FileHandleRep _ NIL;file _ NARROW[SafeStorage.FQNext[MyQueue]];innerFileTableFinalizationProcess[];file _ NIL;ENDLOOP;};SafeStorage.EstablishFinalization[type: CODE[YggFileInternal.FileHandleRep], npr: 1, fq: MyQueue ! SafeStorage.CantEstablishFinalization => CONTINUE;];TRUSTED {Process.Detach[FORK FileTableFinalizationProcess[] ];};}.   V  YggFileTableImpl.mesa - global table of open files (to cause sharing of handles)Copyright ╙ 1985, 1986, 1988 by Xerox Corporation.  All rights reserved.Andrew Birrell  November 15, 1983 3:05 pmLevin, August 8, 1983 6:00 pmSchroeder, June 10, 1983 5:20 pmRovner, November 9, 1983 11:19 amRuss Atkinson (RRA) May 14, 1985 12:35:48 pm PDTBob Hagmann March 14, 1989 7:46:13 am PSTCalled by Lookup and by InsertCalled only by InternalCreate and FileTableFinalizationProcessCalled by Lookup and by AllocForCreateUncomment the next line for non-PrincOps testingIF fh = NIL THEN ERROR; Э╩t  Ш codeЪЬPЩPKЪЬHЩHKЪЬ)Щ)KЩKЩ KЩ!JЩ0KЩ)ЧKЩ Ъ╧k	Ш	KЪЬЭЬШKЪЬЭЬ
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