homework-jianmu/source/libs/sync/src/syncReplication.c

99 lines
3.6 KiB
C

/*
* Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
*
* This program is free software: you can use, redistribute, and/or modify
* it under the terms of the GNU Affero General Public License, version 3
* or later ("AGPL"), as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "syncReplication.h"
#include "syncIndexMgr.h"
#include "syncMessage.h"
#include "syncRaftEntry.h"
#include "syncRaftLog.h"
#include "syncUtil.h"
// TLA+ Spec
// AppendEntries(i, j) ==
// /\ i /= j
// /\ state[i] = Leader
// /\ LET prevLogIndex == nextIndex[i][j] - 1
// prevLogTerm == IF prevLogIndex > 0 THEN
// log[i][prevLogIndex].term
// ELSE
// 0
// \* Send up to 1 entry, constrained by the end of the log.
// lastEntry == Min({Len(log[i]), nextIndex[i][j]})
// entries == SubSeq(log[i], nextIndex[i][j], lastEntry)
// IN Send([mtype |-> AppendEntriesRequest,
// mterm |-> currentTerm[i],
// mprevLogIndex |-> prevLogIndex,
// mprevLogTerm |-> prevLogTerm,
// mentries |-> entries,
// \* mlog is used as a history variable for the proof.
// \* It would not exist in a real implementation.
// mlog |-> log[i],
// mcommitIndex |-> Min({commitIndex[i], lastEntry}),
// msource |-> i,
// mdest |-> j])
// /\ UNCHANGED <<serverVars, candidateVars, leaderVars, logVars>>
//
int32_t syncNodeAppendEntriesPeers(SSyncNode* pSyncNode) {
assert(pSyncNode->state == TAOS_SYNC_STATE_LEADER);
int32_t ret = 0;
for (int i = 0; i < pSyncNode->peersNum; ++i) {
SRaftId* pDestId = &(pSyncNode->peersId[i]);
SyncIndex nextIndex = syncIndexMgrGetIndex(pSyncNode->pNextIndex, pDestId);
SyncIndex preLogIndex = nextIndex - 1;
SyncTerm preLogTerm = 0;
if (preLogIndex >= SYNC_INDEX_BEGIN) {
SSyncRaftEntry* pPreEntry = pSyncNode->pLogStore->getEntry(pSyncNode->pLogStore, preLogIndex);
preLogTerm = pPreEntry->term;
}
SyncIndex lastIndex = syncUtilMinIndex(pSyncNode->pLogStore->getLastIndex(pSyncNode->pLogStore), nextIndex);
assert(nextIndex == lastIndex);
SSyncRaftEntry* pEntry = logStoreGetEntry(pSyncNode->pLogStore, nextIndex);
assert(pEntry != NULL);
SyncAppendEntries* pMsg = syncAppendEntriesBuild(pEntry->bytes);
pMsg->srcId = pSyncNode->myRaftId;
pMsg->destId = *pDestId;
pMsg->prevLogIndex = preLogIndex;
pMsg->prevLogTerm = preLogTerm;
pMsg->commitIndex = pSyncNode->commitIndex;
pMsg->dataLen = pEntry->bytes;
// add pEntry into msg
syncNodeAppendEntries(pSyncNode, pDestId, pMsg);
}
return ret;
}
int32_t syncNodeReplicate(SSyncNode* pSyncNode) {
// start replicate
int32_t ret = syncNodeAppendEntriesPeers(pSyncNode);
return ret;
}
int32_t syncNodeAppendEntries(SSyncNode* pSyncNode, const SRaftId* destRaftId, const SyncAppendEntries* pMsg) {
sTrace("syncNodeAppendEntries pSyncNode:%p ", pSyncNode);
int32_t ret = 0;
SRpcMsg rpcMsg;
syncAppendEntries2RpcMsg(pMsg, &rpcMsg);
syncNodeSendMsgById(destRaftId, pSyncNode, &rpcMsg);
return ret;
}