File: DBIconsImpl.mesa
-- Edited by Teitelman on July 18, 1984 9:12:44 am PDT
-- Edited by: Donahue, August 15, 1984 9:10:47 am PDT
-- Last Edited by: Widom, August 8, 1984 9:14:17 pm PDT
DIRECTORY
FS USING [Error, StreamOpen],
Booting USING [CheckpointProc, RegisterProcs, RollbackProc],
Convert USING [RopeFromCard],
DB,
DBIcons,
IO,
Basics USING[LowHalf],
IOClasses USING [CreateCommentFilterStream ],
DBNames USING[ EntityToName, MakeName],
Icons USING [NewIconFromFile, IconFlavor],
List USING[ DotCons, DottedPair, AList ],
MessageWindow USING [Append, Blink],
Process USING[Ticks, SecondsToTicks, Detach, Pause],
VM USING [AddressFault],
Rope USING [Cat, Equal, ROPE],
UserProfile USING [ Token ]
;
DBIconsImpl: CEDAR MONITOR
IMPORTS Basics, Booting, DBNames, FS, Convert, IO, MessageWindow, VM, Process,
Rope, Icons, DB, List, UserProfile, IOClasses
EXPORTS DBIcons
= BEGIN
OPEN DB, Rope;
Types
Failed: PUBLIC ERROR [why: DBIcons.Failure, reason: Rope.ROPE] = CODE;
ROPE: TYPE = Rope.ROPE;
Global variables for accessing the database
IconRelation: DB.Relation; -- the relation giving the properties of an icon
The tuples in the relation have the structure
IconRelation[ IconNameAttr: ROPE, IconFileAttr: ROPE, IconIndexAttr: INT ]
IconFileAttr: DB.Attribute; -- the name of the file for an icon
IconIndexAttr: DB.Attribute; -- the index in the file
IconNameAttr: DB.Attribute; -- the icon itself (the other attributes are treated as properties)
iconCache: List.AList ← NIL; -- the internal cache of mappings from icon names to flavors
IconDB: PUBLIC ROPE ← NIL;
readOnly: PUBLIC BOOLEAN ← TRUE; -- true if the segment is readonly
activity: BOOLEAN ← FALSE; -- true if a database operation has been performed recently
ticksToWait: Process.Ticks ← Process.SecondsToTicks[5*60];
schemaSet: CONDITION;
Establishing the database
EstablishIconDB: PUBLIC PROC [file: Rope.ROPE ← NIL] = {
IconDB ← IF file = NIL THEN
UserProfile.Token[key: "Icons.Segment", default: "[Luther.Alpine]<CedarDoc>Icons.Segment"] ELSE file;
ResetSchema[];
iconCache ← NIL };
WatchDBActivity: PROC[] = {
WHILE TRUE DO
Process.Pause[ticksToWait];
CheckConnection[]
ENDLOOP
};
CheckConnection: ENTRY PROC[] = {
IF NOT activity THEN
{ trans: DB.Transaction = DB.TransactionOf[$Icons];
IF trans # NIL THEN DB.CloseTransaction[trans]
}; -- don't keep the connection open too long
activity ← FALSE;
};
Accessing Icons
RegisterIcon: PUBLIC ENTRY PROC [iconName: Rope.ROPE, fileName: Rope.ROPE, index: CARDINAL] = {
Changes RegisteredIcons.Catalogue to reflect the indicated association. This definition will replace any previous definition. comments are for inclusion in the catalogue to help the user figure out what the icon looks like.
ENABLE UNWIND => NULL;
[] ← InternalRegisterIcon[iconName, fileName, index]
};
GetIcon: PUBLIC ENTRY PROC [iconName: Rope.ROPE, default: Icons.IconFlavor ← unInit] RETURNS [Icons.IconFlavor] = {
ENABLE UNWIND => NULL;
RETURN[InternalGetIcon[iconName, default]];
};
InternalGetIcon: INTERNAL PROC[iconName: Rope.ROPE, default: Icons.IconFlavor ← unInit] RETURNS [Icons.IconFlavor] = {
Obtain an icon flavor for the icon associated with iconName. Create a new icon flavor if one has not previously been created.
If for some reason it could not obtain the icon, and default # unInit, returns the default. Otherwise, raises Error (defined below) with appropriate parameters.
cachedFlavor: REF ANY = CheckCache[iconName, iconCache];
flavor: Icons.IconFlavor ← unInit;
success: BOOL;
DoGetIcon: PROC[] = {
attributeValue: DB.AttributeValue = [attribute: IconNameAttr, lo: S2V[iconName]];
iconRelship: DB.Relship = DeclareRelship[IconRelation, LIST[attributeValue], OldOnly];
IF iconRelship = NIL THEN {flavor ← default; RETURN};
{ fileName: ROPE = V2S[ GetF[iconRelship, IconFileAttr] ];
index: CARDINAL = Basics.LowHalf[LOOPHOLE[V2I[GetF[iconRelship, IconIndexAttr]]]];
flavor ← Icons.NewIconFromFile[fileName, index !
    FS.Error =>
     IF default # unInit THEN flavor ← default
     ELSE ERROR Failed[fileNotFound, fileName];
   VM.AddressFault =>
     IF default # unInit THEN flavor ← default
     ELSE ERROR
     Failed[invalidIndex, Convert.RopeFromCard[index]]]; -- NewIconFromFile raises this if given badindex.
} };
IF cachedFlavor # NIL THEN RETURN[NARROW[cachedFlavor, REF Icons.IconFlavor]^];
IF IconDB = NIL THEN RETURN[default];
success ← CarefullyApply[DoGetIcon];
IF NOT success THEN RETURN[default];
IF flavor # unInit THEN
{ iconCache ← Cache[ List.DotCons[iconName, NEW[Icons.IconFlavor ← flavor]],
       iconCache ];
RETURN[flavor] };
IF default # unInit THEN RETURN[default];
ERROR Failed[noSuchIcon, iconName]
};
****************** setting/getting icons for entities ****************

-- works for Entities or Domains
SetIcon: PUBLIC PROCEDURE[e: Entity, iconFile: ROPE, fileIndex: CARDINAL] =
BEGIN
name: ROPE = IF DB.IsSystemEntity[e] THEN DB.NameOf[e]
     ELSE DBNames.EntityToName[e, DB.SegmentOf[e]];
  IF IsRegistered[name].file = NIL THEN
  RegisterIcon[ name, iconFile, fileIndex ]
END;
acorn: Icons.IconFlavor = Icons.NewIconFromFile["///Commands/DB.Icons", 0];
GetIconForEntity: PUBLIC ENTRY PROC[eName, domain: ROPE, segment: DB.Segment] RETURNS [Icons.IconFlavor] = {
ENABLE UNWIND => NULL;
IF eName = NIL OR domain = NIL OR segment = NIL THEN RETURN[acorn];
IF Rope.Equal[domain, "Domain"] THEN RETURN[InternalGetIcon[eName, acorn]];
BEGIN
icon: Icons.IconFlavor ← unInit;
fullName: ROPE = DBNames.MakeName[segment, domain, eName];
icon ← InternalGetIcon[fullName ! Failed => CONTINUE];
IF icon # unInit THEN RETURN[icon];
now try the name of the domain of the entity
RETURN[InternalGetIcon[domain, acorn]]
END
};
Cache: INTERNAL PROC[ pair: List.DottedPair, aList: List.AList ] RETURNS[ List.AList ] = {
x, x1: List.AList ← NIL;
x ← aList;
UNTIL x = NIL DO
IF Rope.Equal[NARROW[x.first.key, ROPE], NARROW[pair.key, ROPE]] THEN
BEGIN
x.first.val ← pair.val;
RETURN[aList];
END;
x1←x;
x ← x.rest;
ENDLOOP;
key not found on x
x ← CONS[pair, NIL];
IF x1 = NIL THEN RETURN[x]
ELSE IF x1.rest = NIL THEN x1.rest ← x -- add at end
ELSE ERROR ; -- defensive programming
RETURN[aList];
};
CheckCache: INTERNAL PROC[ name: Rope.ROPE, in: List.AList ] RETURNS[ val: REF ANY ] = {
UNTIL in = NIL DO
IF Rope.Equal[NARROW[in.first.key, Rope.ROPE], name] THEN RETURN[in.first.val];
in ← in.rest;
ENDLOOP;
RETURN[NIL]};
IsRegistered: PUBLIC ENTRY PROC[iconName: Rope.ROPE ← NIL, fileName: Rope.ROPE ← NIL, index: CARDINAL ← LAST[CARDINAL]] RETURNS[name: Rope.ROPE, file: Rope.ROPE, i: CARDINAL] = {
Can be called with either iconName, or (fileName and index); does not force creation of icon flavor (only GetIcon does that).
ENABLE UNWIND => NULL;
DoRegisterCheck: PROC[] =
{ IF iconName # NIL THEN
{ attributeValue: DB.AttributeValue = [attribute: IconNameAttr, lo: S2V[iconName]];
iconRelship: DB.Relship = DeclareRelship[IconRelation, LIST[attributeValue], OldOnly];
IF iconRelship = NIL THEN { file ← NIL; name ← NIL; i ← 0 }
ELSE
{ file ← V2S[ GetF[ iconRelship, IconFileAttr ] ];
i ← Basics.LowHalf[LOOPHOLE[V2I[GetF[iconRelship, IconIndexAttr]]]];
name ← iconName } }
ELSE {
iconRels: RelshipSet = RelationSubset[IconRelation,
       LIST[AttributeValue[IconFileAttr, S2V[fileName]],
         AttributeValue[IconIndexAttr, U2V[index]]]];
iconRel: Relship = NextRelship[iconRels];
ReleaseRelshipSet[iconRels];
IF iconRel = NIL THEN{ file ← NIL; name ← NIL; i ← 0 }
ELSE
{ name ← V2S[GetF[iconRel, IconNameAttr]]; file ← fileName; i ← index } } };
IF NOT CarefullyApply[DoRegisterCheck] THEN RETURN[NIL, NIL, 0]
};
InvalidateCache: PUBLIC ENTRY PROC [iconName: Rope.ROPE ← NIL] = {
If an iconFlavor was previous created for this icon, discard the flavor, i.e. the next call to GetIcon will create a new flavor. If iconName = NIL, do this for all registered icons. For use by iconeditor.
ENABLE UNWIND => NULL;
IF iconName = NIL THEN iconCache ← NIL
ELSE iconCache ← Cache[ List.DotCons[iconName, NIL], iconCache ]
};
InternalRegisterIcon: INTERNAL PROC[iconName: Rope.ROPE, fileName: Rope.ROPE, index: CARDINAL] RETURNS[success: BOOLEAN] = {
DoRegisterIcon: PROC[] = {
attributeValue: DB.AttributeValue = [IconNameAttr, iconName];
iconRel: Relship = DeclareRelship[IconRelation, LIST[attributeValue]];
SetF[iconRel, IconFileAttr, S2V[fileName]];
SetF[iconRel, IconIndexAttr, U2V[index]] };
IF readOnly OR IconDB = NIL THEN RETURN; -- can't register things in this segment
success ← CarefullyApply[DoRegisterIcon]
};
Parsing Icon Catalogues
Parse: INTERNAL PROCEDURE[ stream: IO.STREAM, errlog: IO.STREAM ] = {
OPEN IO;
error: BOOLEAN ← FALSE;
{ ENABLE IO.EndOfStream => GOTO Out;
DO
DBNameProc: IO.BreakProc = {
just scan to a right paren (or be prepared to quit at a CR if you don't find one)
IF char = ') THEN RETURN[break];
RETURN[IF char = CR THEN break ELSE other] };
whiteSpace: IO.BreakProc = {
RETURN[
SELECT char FROM
CR => break,
IO.SP, IO.ESC, IO.LF, IO.TAB, ',, ':, '; => sepr,
ENDCASE => other ]
};
isACR: IO.BreakProc = {
RETURN[IF char = CR THEN break ELSE other]
};
tokenProc: IO.BreakProc = {
RETURN[SELECT char FROM
IO.SP, IO.TAB, ', => sepr,
IO.CR => break,
ENDCASE => other
];
};
iconName, fileName: Rope.ROPE;
index: CARDINAL;
[] ← IO.SkipWhitespace[stream];
IF stream.GetChar[] # '( THEN
{ error ← TRUE;
Report[msg: Rope.Cat["Transaction Aborted at: ",
Convert.RopeFromCard[stream.GetIndex[]]], errLog: errlog];
GOTO Out };
iconName ← IO.GetTokenRope[stream, DBNameProc].token;
IF stream.GetChar[] # ') THEN
{ error ← TRUE;
Report[msg: Rope.Cat["Transaction Aborted at: ",
Convert.RopeFromCard[stream.GetIndex[]]], errLog: errlog];
GOTO Out };
[] ← IO.SkipWhitespace[stream]; -- skip any intervening whitespace
fileName ← IO.GetTokenRope[stream, whiteSpace].token;
index ← IO.GetCard[stream];
IF NOT InternalRegisterIcon[iconName, fileName, index] THEN
{ error ← TRUE;
Report[msg: Rope.Cat["Transaction Aborted at: ",
Convert.RopeFromCard[stream.GetIndex[]]], errLog: errlog];
GOTO Out }
ENDLOOP;
EXITS
Out => NULL;
};
IF error THEN {
MessageWindow.Append["problems encountered in reading icon file."];
MessageWindow.Blink[];
IF errlog # NIL THEN errlog.Close[];
};
};
WriteCatalogue: PUBLIC ENTRY PROC [file: Rope.ROPE] = {
ENABLE UNWIND => NULL;
stream: IO.STREAM;
InternalWrite: PROC[] = {
OPEN IO;
iconRels: RelshipSet = RelationSubset[IconRelation];
FOR r: Relship ← NextRelship[iconRels], NextRelship[iconRels] UNTIL r = NIL DO
fileName: ROPE = V2S[ GetF[IconFileAttr, IconFileAttr] ];
iconName: ROPE = V2S[ GetF[IconFileAttr, IconNameAttr] ];
index: CARDINAL = Basics.LowHalf[LOOPHOLE[V2I[GetF[r, IconIndexAttr]]]];
stream.PutF["\n(%g) %g %d", rope[iconName], rope[fileName], int[index]];
ENDLOOP;
stream.Close[] };
stream ← FS.StreamOpen[file, $append ! FS.Error => {stream ← NIL; CONTINUE}];
IF stream # NIL THEN [] ← CarefullyApply[InternalWrite]
};
Reporting errors
Report: INTERNAL PROCEDURE [msg: Rope.ROPE, errLog: IO.STREAM] = {
OPEN IO;
IF errLog # NIL THEN errLog.PutF["\n\n%g", rope[msg]];
};
Opening, closing segment, making/reading catalogue
OpenUp: Booting.RollbackProc = {
DB.Initialize[nCachePages: 256];
InvalidateCache[] };
CloseTrans: Booting.CheckpointProc = {
DB.CloseTransaction[trans: DB.TransactionOf[segment: $Icons]] };
ResetSchema: ENTRY PROC[] = {
ENABLE UNWIND => NULL;
success: BOOLEAN;
activity ← TRUE;
IF DB.TransactionOf[$Icons] # NIL THEN RETURN;
[success, readOnly] ← SetUpSegment[];
IF NOT success THEN RETURN;
IF NOT DB.Null[IconRelation] THEN
{ BROADCAST schemaSet; RETURN }; -- all is well, don't bother flushing cache
IconRelation ← DeclareRelation[ "IconInfo", $Icons ];
IconFileAttr ← DeclareAttribute[IconRelation, "file", RopeType];
IconIndexAttr ← DeclareAttribute[IconRelation, "index", IntType];
IconNameAttr ← DeclareAttribute[IconRelation, "name", RopeType, Key];
[] ← DeclareIndex[IconRelation, LIST[IconNameAttr]];
iconCache ← NIL;
BROADCAST schemaSet };
ReadCatalogue: PUBLIC ENTRY PROC[file: Rope.ROPE, errlog: IO.STREAM ← NIL] = TRUSTED {
ENABLE UNWIND => NULL;
stream: IO.STREAM;
stream ← FS.StreamOpen[file ! FS.Error => { stream ← NIL; CONTINUE }];
IF stream = NIL THEN RETURN;
stream ← IOClasses.CreateCommentFilterStream[stream];
Parse[ stream, errlog ];
DB.MarkTransaction[DB.TransactionOf[$Icons]] };
CarefullyApply: INTERNAL PROC [proc: PROC[]] RETURNS [succeeded: BOOL] ~ {
ENABLE DB.Error, DB.Failure, DB.Aborted => {succeeded ← FALSE; GOTO Quit};
transactionToBeAborted: DB.Transaction ← NIL;
succeeded ← TRUE;
proc[ ! DB.Aborted => { transactionToBeAborted ← trans; succeeded ← FALSE; CONTINUE };
DB.Error => {IF code # TransactionNotOpen THEN REJECT; succeeded ← FALSE; CONTINUE} ];
IF succeeded THEN RETURN; -- no aborted occurred
IF transactionToBeAborted # NIL THEN DB.AbortTransaction[transactionToBeAborted];
TRUSTED {Process.Detach[ FORK ResetSchema[] ]};
WAIT schemaSet; -- ResetSchema is doing its job since we forked it
proc[]; -- don't bother trying to restart here --
succeeded ← TRUE;
EXITS
Quit => NULL;
};
SetUpSegment: INTERNAL PROC [] RETURNS [success: BOOL, readOnly: BOOL] ~ {
ENABLE DB.Aborted, DB.Failure, DB.Error => {success ← FALSE; CONTINUE};
segment: ATOM = $Icons;
readOnly ← FALSE;
success ← TRUE;
DB.Initialize[nCachePages: 256];
IF DB.TransactionOf[segment] # NIL THEN
{readOnly← DB.GetSegmentInfo[segment].readOnly; RETURN};
DB.DeclareSegment[IconDB, segment, 140B, FALSE];
DB.OpenTransaction[segment !
DB.Error => TRUSTED {
success← FALSE;
SELECT code FROM
ProtectionViolation => {readOnly ← TRUE; CONTINUE};
ENDCASE => GOTO AlreadyDone} ];
IF success THEN GOTO AlreadyDone;
readOnly must be true to get here; try opening the segment for reading
DB.CloseTransaction[DB.TransactionOf[segment]];
DB.DeclareSegment[IconDB, segment, 140B, TRUE];
DB.OpenTransaction[segment];
IF NOT success THEN DB.CloseTransaction[DB.TransactionOf[segment]]
EXITS
AlreadyDone => NULL
};
Initialization
TRUSTED {
Booting.RegisterProcs[c: CloseTrans, r: OpenUp];
EstablishIconDB[];
Process.Detach[ FORK WatchDBActivity[] ] };
END.