[Cyan]<Cedar6.1>GrapevineUser>GVProtocol.mesa!1

GVProtocol.mesa - subroutines for mail and reg server protocols

Andrew Birrell June 22, 1983 6:02 pm

Levin, September 22, 1983 10:38 am

Hal Murray, May 12, 1986 9:57:44 pm PDT

DIRECTORY

Endian USING [HWORD],

GVBasics USING [Connect, ItemHeader, GVString, oldestTime, Password, Remark, RName, Timestamp],

GVNames USING [RSOperation],

IO USING [STREAM, UnsafeBlock],

Pup USING [Address, Socket],

Rope USING [ROPE];

GVProtocol: CEDAR DEFINITIONS = {

SetTestingMode: PROC;

set sockets for test-only mode

GVSocket: TYPE = { -- socket numbers are hidden, because they differ in testing mode

none, -- use socket number in host address

RSEnquiry, -- database operations

RSPoll, -- "are you there" probes

Lily, -- Lily terminal service

MSPoll, -- "are you there" probes

MSForward, -- internal forwarding protocol

MSSend, -- mail submission protocol

MSRetrieve -- mail retrieval

};

GetSocket: PROC [gv: GVSocket] RETURNS [Pup.Socket];

endSST: [0..256) = 1;

BSP "mark" byte used in Server-Server and ReadMail protocols

IsLocal: PROC [addr: Pup.Address] RETURNS [BOOLEAN ];

Whether the address is on this host

Handle: TYPE = IO.STREAM;

FailureReason: TYPE = { communicationError, noData, protocolError, clientError };

"communicationError" means some error pup arrived; "noData" means the stream is still there, but no data; "protocolError" means we cant understand him

Failed: SIGNAL [why: FailureReason, text: Rope.ROPE];

may be raised by any of the following procedures,

except DestroyStream.

CreateStream: PROC [host: Pup.Address, socket: GVSocket, secs: INT ← 120 ]

RETURNS[ Handle ];

Create stream, with given timeout for data

SendNow: PROC [str: Handle];

Close: PROC [str: Handle];

The following procedures provide type-safe access to the communication protocols. Note that sending characters directly on the stream is not always correct if they have one of these types. These procedures implement any conversion needed between Cedar internal representation and the Grapevine protocols.

SendAck: PROC [str: Handle];

ReceiveAck: PROC [str: Handle];

SendBoolean: PROC [str: Handle, bool: BOOL];

ReceiveBoolean: PROC [str: Handle] RETURNS [BOOL];

Byte: TYPE = [0..256);

SendByte: PROC [str: GVProtocol.Handle, byte: Byte];

ReceiveByte: PROC [str: GVProtocol.Handle] RETURNS [byte: Byte];

SendCount: PROC [str: Handle, count: Endian.HWORD];

ReceiveCount: PROC [str: Handle] RETURNS [count: Endian.HWORD];

SendItemHeader: PROC [str: Handle, header: GVBasics.ItemHeader];

transmits the header.

ReceiveItemHeader: PROC [str: Handle] RETURNS [header: GVBasics.ItemHeader];

receive header of item from stream.

SendTimestamp: PROC [str: Handle, stamp: GVBasics.Timestamp];

sends a Timestamp value over the stream.

ReceiveTimestamp: PROC [str: Handle] RETURNS [stamp: GVBasics.Timestamp];

receives a timestamp from the stream.

SendPassword: PROC [str: Handle, pw: GVBasics.Password];

ReceivePassword: PROC [str: Handle] RETURNS[pw: GVBasics.Password];

SendRC: PROC [str: Handle, rc: ReturnCode];

sends a return code value over the stream.

ReceiveRC: PROC [str: Handle] RETURNS [rc: ReturnCode];

receives a return code value from the stream.

SendMSOperation: PROC [str: Handle, op: MSOperation];

ReceiveMSOperation: PROC [str: Handle] RETURNS [op: MSOperation];

SendRSOperation: PROC [str: Handle, op: GVNames.RSOperation];

ReceiveRSOperation: PROC [str: Handle] RETURNS [op: GVNames.RSOperation];

SendBytes: PROC [str: GVProtocol.Handle, block: IO.UnsafeBlock];

ReceiveBytes: UNSAFE PROC [str: GVProtocol.Handle, block: IO.UnsafeBlock];

StringSize: PROC [str: GVBasics.GVString] RETURNS [INT];

the number of words occupied by protocol representation of a string

SendRName: PROC [str: Handle, name: GVBasics.RName];

transmits the contents of the R-Name.

ReceiveRName: PROC [str: Handle] RETURNS [GVBasics.RName];

SendConnect: PROC [str: Handle, connect: GVBasics.Connect];

sends the connect-site name as a Mesa string. "connect.length" should be < maxConnectLength

ReceiveConnect: PROC [str: Handle] RETURNS [GVBasics.Connect];

SendRemark: PROC [str: Handle, remark: GVBasics.Remark];

-- sends the remark as a Mesa string. "remark.length" should be < maxRemarkLength --

ReceiveRemark: PROC [str: Handle] RETURNS[GVBasics.Remark];

ReceiveGVString: PROC [str: GVProtocol.Handle] RETURNS[GVBasics.GVString];

Receive a string in GV protocol format

ReceiveFunnyString: PROC [str: Handle] RETURNS [GVBasics.RName];

Skip maxLength when sent in the middle of a bigger thing.

This is only used by GVNamesImpl to get the Remark and Connect fields.

SendGVString: PROC [str: GVProtocol.Handle, rope: GVBasics.GVString];

Send a string in GV protocol format.

SendRope: PROC [str: GVProtocol.Handle, rope: Rope.ROPE];

Send the characters of the rope with no extra protocol information

Enquire: PROC [

str: Handle,

op: GVNames.RSOperation,

name: GVBasics.RName,

oldStamp: GVBasics.Timestamp ← GVBasics.oldestTime]

RETURNS [rc: ReturnCode, stamp: GVBasics.Timestamp];

Sends an enquiry on the stream

ReceiveRList: PROC [str: Handle, work: PROC [GVBasics.RName] ];

receives a sequence of R-Names from the stream, calling "work" for each R-Name.

MSOperation: TYPE = MACHINE DEPENDENT {

openMBX(0),

nextMessage(1),

readTOC(2),

readMessage(3),

writeTOC(4),

deleteMessage(5),

flushMBX(6),

restartMBX(7),

startSend(20),

addRecipient(21),

checkValidity(22),

startItem(23),

addToItem(24),

send(26),

expand(27),

getStamp(28),

(255)

};

RNameType: TYPE = MACHINE DEPENDENT {

status of an RName, given in an R-Server reply.

group(0), -- group of names

individual(1), -- person or machine

notFound(2), -- the R-Name does not exist

dead(3), -- the R-Name has been deleted from the database

(255) };

Code: TYPE = MACHINE DEPENDENT {

result of an R-Server operation.

done(0), -- operation succeeded

noChange(1), -- enquiry: given stamp was still valid

update: operation wouldn't change the database

outOfDate(2), -- update: more recent info was in database (!)

NotAllowed(3), -- update: operation prevented by access controls

BadOperation(4), -- unknown operation number

BadProtocol(5), -- protocol violation (e.g. list out of order)

BadRName(6), -- R-Name does not exist or has wrong type

BadPassword(7), -- what it says

WrongServer(8), -- the R-Name's registry is not in this R-Server

AllDown(9), -- remote R-Server was down for ACL enquiry

(255) };

ReturnCode: TYPE = MACHINE DEPENDENT RECORD [

code: Code, type: RNameType];