Merge #11043: Use std::unique_ptr (C++11) where possible

a357293 Use MakeUnique<Db>(...) (practicalswift)
3e09b39 Use MakeUnique<T>(...) instead of std::unique_ptr<T>(new T(...)) (practicalswift)
8617989 Add MakeUnique (substitute for C++14 std::make_unique) (practicalswift)
d223bc9 Use unique_ptr for pcoinscatcher/pcoinsdbview/pcoinsTip/pblocktree (practicalswift)
b45c597 Use unique_ptr for pdbCopy (Db) and fix potential memory leak (practicalswift)
29ab96d Use unique_ptr for dbenv (DbEnv) (practicalswift)
f72cbf9 Use unique_ptr for pfilter (CBloomFilter) (practicalswift)
8ccf1bb Use unique_ptr for sem{Addnode,Outbound} (CSemaphore) (practicalswift)
73db063 Use unique_ptr for upnp_thread (boost::thread) (practicalswift)
0024531 Use unique_ptr for dbw (CDBWrapper) (practicalswift)
fa6d122 Use unique_ptr:s for {fee,short,long}Stats (TxConfirmStats) (practicalswift)
5a6f768 Use unique_ptr for httpRPCTimerInterface (HTTPRPCTimerInterface) (practicalswift)
860e912 Use unique_ptr for pwalletMain (CWallet) (practicalswift)

Pull request description:

  Use `std::unique_ptr` (C++11) where possible.

  Rationale:
  1. Avoid resource leaks (specifically: forgetting to `delete` an object created using `new`)
  2. Avoid undefined behaviour (specifically: double `delete`:s)

  **Note to reviewers:** Please let me know if I've missed any obvious `std::unique_ptr` candidates. Hopefully this PR should cover all the trivial cases.

Tree-SHA512: 9fbeb47b800ab8ff4e0be9f2a22ab63c23d5c613a0c6716d9183db8d22ddbbce592fb8384a8b7874bf7375c8161efb13ca2197ad6f24b75967148037f0f7b20c

1 files changed, 10 insertions, 10 deletions

diff --git a/src/validation.cpp b/src/validation.cpp
index efabe6293..e7b6fc52a 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -201,9 +201,9 @@ CBlockIndex* FindForkInGlobalIndex(const CChain& chain, const CBlockLocator& loc
     return chain.Genesis();
 }
 
-CCoinsViewDB *pcoinsdbview = nullptr;
-CCoinsViewCache *pcoinsTip = nullptr;
-CBlockTreeDB *pblocktree = nullptr;
+std::unique_ptr<CCoinsViewDB> pcoinsdbview;
+std::unique_ptr<CCoinsViewCache> pcoinsTip;
+std::unique_ptr<CBlockTreeDB> pblocktree;
 
 enum FlushStateMode {
     FLUSH_STATE_NONE,
@@ -295,7 +295,7 @@ bool CheckSequenceLocks(const CTransaction &tx, int flags, LockPoints* lp, bool
     }
     else {
         // pcoinsTip contains the UTXO set for chainActive.Tip()
-        CCoinsViewMemPool viewMemPool(pcoinsTip, mempool);
+        CCoinsViewMemPool viewMemPool(pcoinsTip.get(), mempool);
         std::vector<int> prevheights;
         prevheights.resize(tx.vin.size());
         for (size_t txinIndex = 0; txinIndex < tx.vin.size(); txinIndex++) {
@@ -424,7 +424,7 @@ void UpdateMempoolForReorg(DisconnectedBlockTransactions &disconnectpool, bool f
     mempool.UpdateTransactionsFromBlock(vHashUpdate);
 
     // We also need to remove any now-immature transactions
-    mempool.removeForReorg(pcoinsTip, chainActive.Tip()->nHeight + 1, STANDARD_LOCKTIME_VERIFY_FLAGS);
+    mempool.removeForReorg(pcoinsTip.get(), chainActive.Tip()->nHeight + 1, STANDARD_LOCKTIME_VERIFY_FLAGS);
     // Re-limit mempool size, in case we added any transactions
     LimitMempoolSize(mempool, gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000, gArgs.GetArg("-mempoolexpiry", DEFAULT_MEMPOOL_EXPIRY) * 60 * 60);
 }
@@ -557,7 +557,7 @@ static bool AcceptToMemoryPoolWorker(const CChainParams& chainparams, CTxMemPool
         LockPoints lp;
         {
         LOCK(pool.cs);
-        CCoinsViewMemPool viewMemPool(pcoinsTip, pool);
+        CCoinsViewMemPool viewMemPool(pcoinsTip.get(), pool);
         view.SetBackend(viewMemPool);
 
         // do all inputs exist?
@@ -2105,7 +2105,7 @@ bool static DisconnectTip(CValidationState& state, const CChainParams& chainpara
     // Apply the block atomically to the chain state.
     int64_t nStart = GetTimeMicros();
     {
-        CCoinsViewCache view(pcoinsTip);
+        CCoinsViewCache view(pcoinsTip.get());
         assert(view.GetBestBlock() == pindexDelete->GetBlockHash());
         if (DisconnectBlock(block, pindexDelete, view) != DISCONNECT_OK)
             return error("DisconnectTip(): DisconnectBlock %s failed", pindexDelete->GetBlockHash().ToString());
@@ -2235,7 +2235,7 @@ bool static ConnectTip(CValidationState& state, const CChainParams& chainparams,
     int64_t nTime3;
     LogPrint(BCLog::BENCH, "  - Load block from disk: %.2fms [%.2fs]\n", (nTime2 - nTime1) * MILLI, nTimeReadFromDisk * MICRO);
     {
-        CCoinsViewCache view(pcoinsTip);
+        CCoinsViewCache view(pcoinsTip.get());
         bool rv = ConnectBlock(blockConnecting, state, pindexNew, view, chainparams);
         GetMainSignals().BlockChecked(blockConnecting, state);
         if (!rv) {
@@ -2413,7 +2413,7 @@ static bool ActivateBestChainStep(CValidationState& state, const CChainParams& c
         // any disconnected transactions back to the mempool.
         UpdateMempoolForReorg(disconnectpool, true);
     }
-    mempool.check(pcoinsTip);
+    mempool.check(pcoinsTip.get());
 
     // Callbacks/notifications for a new best chain.
     if (fInvalidFound)
@@ -3275,7 +3275,7 @@ bool TestBlockValidity(CValidationState& state, const CChainParams& chainparams,
 {
     AssertLockHeld(cs_main);
     assert(pindexPrev && pindexPrev == chainActive.Tip());
-    CCoinsViewCache viewNew(pcoinsTip);
+    CCoinsViewCache viewNew(pcoinsTip.get());
     CBlockIndex indexDummy(block);
     indexDummy.pprev = pindexPrev;
     indexDummy.nHeight = pindexPrev->nHeight + 1;