Refactor FML|HS to use state machine

Instead of responding based on the packet type received, maintain a
local state and ensure the correct packets are received. Should help
avoid unexpected states/behavior. See:
https://github.com/ORelio/Minecraft-Console-Client/pull/100/files#diff-65b97c02a9736311374109e22d30ca9cR297
This commit is contained in:
deathcap 2016-01-23 19:26:50 -08:00
parent 8fd30f6af9
commit 6c33ec2856

View file

@ -1,5 +1,6 @@
var mc = require('minecraft-protocol'); var mc = require('minecraft-protocol');
var ProtoDef = require('protodef').ProtoDef; var ProtoDef = require('protodef').ProtoDef;
var assert = require('assert');
if(process.argv.length < 4 || process.argv.length > 6) { if(process.argv.length < 4 || process.argv.length > 6) {
console.log("Usage : node echo.js <host> <port> [<name>] [<password>]"); console.log("Usage : node echo.js <host> <port> [<name>] [<password>]");
@ -200,12 +201,25 @@ function writeAck(client, phase) {
}); });
} }
var FMLHandshakeClientState = {
START: 1,
WAITINGSERVERDATA: 2,
WAITINGSERVERCOMPLETE: 3,
PENDINGCOMPLETE: 4,
COMPLETE: 5,
};
function fmlHandshakeStep(client, data) function fmlHandshakeStep(client, data)
{ {
var parsed = proto.parsePacketBuffer('FML|HS', data); var parsed = proto.parsePacketBuffer('FML|HS', data);
console.log('FML|HS',parsed); console.log('FML|HS',parsed);
if (parsed.data.discriminator === 'ServerHello') { var fmlHandshakeState = client.fmlHandshakeState || FMLHandshakeClientState.START;
switch(fmlHandshakeState) {
case FMLHandshakeClientState.START:
{
assert.ok(parsed.data.discriminator === 'ServerHello', `expected ServerHello in START state, got ${parsed.data.discriminator}`);
if (parsed.data.fmlProtocolVersion > 2) { if (parsed.data.fmlProtocolVersion > 2) {
// TODO: support higher protocols, if they change // TODO: support higher protocols, if they change
} }
@ -235,24 +249,53 @@ function fmlHandshakeStep(client, data)
data: modList data: modList
}); });
writeAck(client, 2); // WAITINGSERVERDATA writeAck(client, 2); // WAITINGSERVERDATA
} else if (parsed.data.discriminator === 'ModList') { client.fmlHandshakeState = FMLHandshakeClientState.WAITINGSERVERDATA;
break;
}
case FMLHandshakeClientState.WAITINGSERVERDATA:
{
assert.ok(parsed.data.discriminator === 'ModList', `expected ModList in WAITINGSERVERDATA state, got ${parsed.data.discriminator}`);
console.log('Server ModList:',parsed.data.mods); console.log('Server ModList:',parsed.data.mods);
// TODO: client/server check if mods compatible // TODO: client/server check if mods compatible
client.fmlHandshakeState = FMLHandshakeClientState.WAITINGSERVERCOMPLETE;
break;
}
} else if (parsed.data.discriminator === 'RegistryData') { case FMLHandshakeClientState.WAITINGSERVERCOMPLETE:
{
assert.ok(parsed.data.discriminator === 'RegistryData', `expected RegistryData in WAITINGSERVERCOMPLETE, got ${parsed.data.discriminator}`);
console.log('RegistryData',parsed.data); console.log('RegistryData',parsed.data);
// TODO: support <=1.7.10 single registry, https://github.com/ORelio/Minecraft-Console-Client/pull/100/files#diff-65b97c02a9736311374109e22d30ca9cR297
if (parsed.data.hasMore === false) { if (parsed.data.hasMore === false) {
console.log('LAST RegistryData'); console.log('LAST RegistryData');
writeAck(client, 3); // WAITINGSERVERCOMPLETE writeAck(client, 3); // WAITINGSERVERCOMPLETE
client.fmlHandshakeState = FMLHandshakeClientState.PENDINGCOMPLETE;
} }
} else if (parsed.data.discriminator === 'HandshakeAck') { break;
if (parsed.data.phase === 2) { // WAITINGCACK }
case FMLHandshakeClientState.PENDINGCOMPLETE:
{
assert.ok(parsed.data.discriminator === 'HandshakeAck', `expected HandshakeAck in PENDINGCOMPLETE, got ${parsed.data.discrimnator}`);
assert.ok(parsed.data.phase === 2, `expected HandshakeAck phase WAITINGACK, got ${parsed.data.phase}`);
writeAck(client, 4); // PENDINGCOMPLETE writeAck(client, 4); // PENDINGCOMPLETE
} else if (parsed.data.phase === 3) { // COMPLETE client.fmlHandshakeState = FMLHandshakeClientState.COMPLETE
break;
}
case FMLHandshakeClientState.COMPLETE:
{
assert.ok(parsed.data.phase === 3, `expected HandshakeAck phase COMPLETE, got ${parsed.data.phase}`);
writeAck(client, 5); // COMPLETE writeAck(client, 5); // COMPLETE
console.log('HandshakeAck Complete!'); console.log('HandshakeAck Complete!');
break;
} }
default:
console.error(`unexpected FML state ${fmlHandshakeState}`);
} }
} }