-- File: CourierImplU.mesa - last edit: -- AOF 27-Oct-87 21:15:13 -- Copyright (C) 1984, 1985, 1986, 1987 by Xerox Corporation. All rights reserved. DIRECTORY Courier USING [ Arguments, Description, Error, ErrorCode, Handle, InvalidArguments, LocalSystemElement, Parameters, RemoteErrorSignalled, VersionMismatch, VersionRange], CourierInternal USING [ activeTimeout, AugmentedStream, Closed, CreateDefaultStream, doStats, ExchWords, inputOptions, RegisterTransport, seal, VersExchProcType, SetBulkStream, SetMessageProtocolVersion, stats, streamDefaultWaitTime, ttDefault, UserConnection], CourierOps USING [ DeleteStream, Fetch, FlushToEndOfMessage, GetBlock, PutBlock, SetIdleWatcher, Store], CourierProtocol USING [ dataSST, Protocol, Protocol3Body, ProtocolRange, pvHigh, RejectCode], Environment USING [bytesPerWord], Process USING [CancelAbort, GetCurrent], Stream USING [Handle, TimeOut], System USING [GetGreenwichMeanTime, nullNetworkNumber]; CourierImplU: PROGRAM IMPORTS Courier, CourierInternal, CourierOps, Process, Stream, System EXPORTS Courier = BEGIN --Implementation of the Courier User. --LOCAL VARIABLES/CONSTANTS uniqueTransaction: CARDINAL = 0; bpw: CARDINAL = Environment.bytesPerWord; maxSecondsWaitable: LONG CARDINAL = LAST[LONG CARDINAL] / 1000; pvEqual: CourierProtocol.Protocol = CourierProtocol.pvHigh; Call: PUBLIC PROC[ cH: Courier.Handle, procedureNumber: CARDINAL, arguments, results: Courier.Parameters, timeoutInSeconds: LONG CARDINAL, requestDataStream: BOOLEAN, streamCheckoutProc: PROC[cH: Courier.Handle]] RETURNS[sH: Stream.Handle] = BEGIN versExchDone: BOOLEAN Ź TRUE; error: Courier.ErrorCode Ź noError; ch: CourierInternal.UserConnection Ź LOOPHOLE[cH]; connectionless: BOOLEAN Ź FALSE; --delete stream after call? SELECT TRUE FROM (ch = NIL), (ch.seal # CourierInternal.seal) => RETURN WITH ERROR Courier.Error[invalidHandle]; (ch.streamState = busy), (ch.streamState = out) => RETURN WITH ERROR Courier.Error[streamNotYours]; ENDCASE; BEGIN ENABLE BEGIN UNWIND => CourierOps.SetIdleWatcher[ch]; --start clocking the stream Courier.Error => --delete the stream on those errors that leave a broken stream around SELECT errorCode FROM transportTimeout => CourierOps.DeleteStream[ch]; noRouteToSystemElement => CourierOps.DeleteStream[ch]; ENDCASE; Stream.TimeOut => --timeout waiting for results or processing same BEGIN error Ź IF (System.GetGreenwichMeanTime[] < ch.clock) THEN transportTimeout ELSE returnTimedOut; GOTO delete; --gun the stream in any case END; --signal raised locally; translate to Error Courier.InvalidArguments => {error Ź invalidArguments; GOTO delete}; --cases where server closed stream | pseudo-version mismatch CourierInternal.Closed => {CourierOps.DeleteStream[ch]; RETRY}; END; ch.owner Ź Process.GetCurrent[]; --record current owner ch.streamState Ź busy; --and lock the stream IF (ch.transFilter = NIL) THEN BEGIN --set up default transport if nobody has registered one for this connection. IF ch.createTransport = NIL THEN CourierInternal.RegisterTransport[ cH, CourierInternal.CreateDefaultStream, CourierInternal.ttDefault]; [ch.transFilter, ch.protocolRange, connectionless] Ź ch.createTransport[ch]; << Protocol version arbitration. The transport filter tells us what our low and high is, because transports that are not connection-oriented need to piggyback the version numbers (which can only be done if low = high). >> CourierOps.PutBlock[ ch, [@ch.protocolRange, 0, SIZE[CourierProtocol.ProtocolRange] * bpw]]; CourierInternal.SetMessageProtocolVersion[ch, pvEqual]; --has to be CourierInternal.SetBulkStream[ch]; --build up the bulk stream ch.versExchProc Ź VersExchProc; --proc to deal with version exchanges END; sH Ź @ch.transFilter.object; --Transmit call message WITH ch.message SELECT FROM protocol3 => BEGIN protocol3Body Ź [call[ transaction: uniqueTransaction, program: CourierInternal.ExchWords[ch.object.programNumber], version: ch.object.versionNumber, procedure: procedureNumber]]; CourierOps.PutBlock[ch, [@protocol3Body, 0, SIZE[call CourierProtocol.Protocol3Body] * bpw]]; END; ENDCASE; --Append client arguments IF (arguments.location # NIL) AND (arguments.description # NIL) THEN CourierOps.Fetch[ch, arguments.location, arguments.description]; sH.sendNow[sH, TRUE]; --transmit and set endRecord IF CourierInternal.doStats THEN BEGIN CourierInternal.stats[callsTransmitted] Ź CourierInternal.stats[callsTransmitted] + 1; IF (ch.object.remote.net = System.nullNetworkNumber) OR (ch.object.remote.net = Courier.LocalSystemElement[].net) THEN CourierInternal.stats[localCallsTransmitted] Ź CourierInternal.stats[localCallsTransmitted] + 1; END; --Bulk data, version 2 IF streamCheckoutProc # NIL THEN BEGIN << Bulk stream is already set in the object, here we are just allowing client to use it. This is really a crock! >> ch.streamState Ź out; ch.lastSST Ź CourierProtocol.dataSST; sH.setTimeout[sH, CourierInternal.streamDefaultWaitTime]; streamCheckoutProc[cH]; Process.CancelAbort[Process.GetCurrent[]]; ch.streamState Ź busy; sH.setSST[sH, CourierProtocol.dataSST]; END; sH.options Ź CourierInternal.inputOptions; IF timeoutInSeconds > maxSecondsWaitable THEN BEGIN ch.clock Ź [LAST[LONG CARDINAL]]; sH.setTimeout[sH, LAST[LONG CARDINAL]]; END ELSE BEGIN ch.clock Ź [System.GetGreenwichMeanTime[] + timeoutInSeconds]; sH.setTimeout[sH, timeoutInSeconds * 1000]; END; << IF ch.versExchProc is NIL then the version exchange is complete. If it isn't then we still have to deal with this situation. >> SELECT TRUE FROM (ch.versExchProc = NIL) => NULL; --this has already been done ((error Ź ch.versExchProc[ch]) # noError) => GOTO delete; ENDCASE; --if it endcased then it passed the version test BEGIN ENABLE ABORTED => GOTO aborted; --Wait for return message to arrive ch.endRecord Ź FALSE; --just in case it was left over WITH ch.message SELECT FROM protocol3 => BEGIN CourierOps.GetBlock[ch, [@protocol3Body, 0, 4]]; ch.clock Ź [LAST[LONG CARDINAL]]; --disallow 'returnTimedOut' sH.setTimeout[sH, CourierInternal.activeTimeout]; WITH p3b: protocol3Body SELECT FROM return => NULL; abort => P3Abort[ch, @p3b]; reject => P3Reject[ch, @p3b]; ENDCASE => ERROR Courier.Error[invalidMessage]; END; ENDCASE; END; --enable aborted --only return message types get here...all others signal and never return IF CourierInternal.doStats THEN CourierInternal.stats[returnsReceived] Ź CourierInternal.stats[returnsReceived] + 1; --now receive and store the client's results IF (results.location # NIL) AND (results.description # NIL) THEN CourierOps.Store[ch, results.location, results.description ! UNWIND => [] Ź CourierOps.FlushToEndOfMessage[ch]]; IF CourierOps.FlushToEndOfMessage[ch] THEN ERROR Courier.Error[parameterInconsistency]; --Bulk data, version 1 IF requestDataStream THEN BEGIN --the bulkFilter.object has already been set. ch.streamState Ź out; sH.setTimeout[sH, CourierInternal.streamDefaultWaitTime]; ch.object.sH Ź sH; END ELSE BEGIN --transport is not connection oriented, delete stream now. IF connectionless THEN CourierOps.DeleteStream[ch] ELSE CourierOps.SetIdleWatcher[ch]; --idles the stream sH Ź NIL; --client gets nothing if he doesn't ask END; EXITS delete => {CourierOps.DeleteStream[ch]; ERROR Courier.Error[error]}; aborted => {CourierOps.DeleteStream[ch]; ERROR ABORTED}; END; --encompasses entire module END; --Call VersExchProc: CourierInternal.VersExchProcType = BEGIN hisRange: CourierProtocol.ProtocolRange; ch.endRecord Ź FALSE; --just like starting out fresh CourierOps.GetBlock[ ch, [@hisRange, 0, SIZE[CourierProtocol.ProtocolRange] * bpw]]; code Ź IF pvEqual IN[hisRange.low..hisRange.high] THEN noError ELSE protocolMismatch; ch.endRecord Ź FALSE; --just in case he sent it with the version #s NARROW[ch, CourierInternal.UserConnection].versExchProc Ź NIL; --fini END; --VersExchProc P3Abort: PROC [ ch: CourierInternal.UserConnection, abort: LONG POINTER TO abort CourierProtocol.Protocol3Body] = BEGIN << We have received an "abort" response from the remote procedure. We have to translate that to an ERROR RemoteErrorSignalled and allow the client to extract the data from the error. Once the parameters are set up, it looks just like a normal return. >> AbortDescription: Courier.Arguments = --PROC[argumentsRecord: Courier.Parameters]; BEGIN IF (argumentsRecord.location # NIL) AND (argumentsRecord.description # NIL) THEN CourierOps.Store[ ch, argumentsRecord.location, argumentsRecord.description]; IF CourierOps.FlushToEndOfMessage[ch] THEN ERROR Courier.Error[parameterInconsistency]; END; --Get the remainder of the abort message. CourierOps.GetBlock[ch, [@abort.abort, 0, SIZE[CARDINAL]*bpw]]; IF CourierInternal.doStats THEN CourierInternal.stats[abortsReceived] Ź CourierInternal.stats[abortsReceived] + 1; ERROR Courier.RemoteErrorSignalled[abort.abort, AbortDescription]; END; P3Reject: PROC[ ch: CourierInternal.UserConnection, reject: LONG POINTER TO reject CourierProtocol.Protocol3Body] = BEGIN CourierOps.GetBlock[ch, [@reject.rejectBody, 0, (SIZE[CourierProtocol.RejectCode] * bpw)]]; WITH v: reject SELECT FROM --just how ugly can we make this? noSuchVersionNumber => --how many times would we like to test these bits? CourierOps.GetBlock[ch, --and fill in a couple more bytes of data [@v.range, 0, (SIZE[Courier.VersionRange] * bpw)]]; ENDCASE; [] Ź CourierOps.FlushToEndOfMessage[ch]; --was there anything left? IF CourierInternal.doStats THEN CourierInternal.stats[rejectsReceived] Ź CourierInternal.stats[rejectsReceived] + 1; WITH rb: reject SELECT FROM --finally raise the error noSuchProgramNumber => ERROR Courier.Error[noSuchProgramNumber]; noSuchVersionNumber => ERROR Courier.VersionMismatch[rb.range]; noSuchProcedureValue => ERROR Courier.Error[noSuchProcedureNumber]; invalidArguments => ERROR Courier.Error[invalidArguments]; ENDCASE => ERROR Courier.Error[unknownErrorInRemoteProcedure]; END; END..... -- of CourierImplU.mesa LOG 30-Jan-85 19:55:55 AOF Post Klamath. 29-Jun-84 10:23:39 SMA Factor Courier from NetworkStreams. 2-Jul-84 16:33:35 SMA Get rid of ch.sH. 9-Oct-84 12:59:06 SMA Remove dependency on NSTypes.WaitTime. 26-Nov-84 15:08:21 SMA Version arbitration back into Courier. 29-Nov-84 9:32:57 SMA Delete stream after call if transport is connectionless. 21-Dec-84 13:08:06 SMA AugmentedStreams and new interfaces. 31-Dec-84 8:29:12 AOF SetSST before placing call on old transport. 7-Jan-85 17:05:04 SMA No more callerAborted translating. 10-Jan-85 14:36:21 SMA bulkFilter set when transport created. 30-Jan-85 19:56:07 AOF Code byte squeezing. 5-Feb-85 18:06:48 SMA Don't try to delete stream when error is invalidHandle. 12-Mar-85 10:57:28 AOF Moved createTimeout and hopWeight to CourierImplM. 8-Apr-85 16:59:47 AOF Delete stream when client aborts waiting for results. 31-May-85 16:50:14 AOF Check Courier.errorCode for parmInc before delete sH. 12-Nov-86 15:30:23 AOF P3.Abort: First get the error code, then test it 16-Jan-87 10:14:10 AOF Removal of Courier Version 2.0 23-Oct-87 19:03:14 AOF And then try to figure out a way to support vers exch.