Merge #16443: refactor: have CCoins* data managed under CChainState

582d2cd74754d6b9a2394616a9c82a89d2d71976 Cover UTXO set access with lock annotations (James O'Beirne)
569353068568444a25b301bbd6513bb510157dc9 refactor: have CCoins* data managed under CChainState (James O'Beirne)
fae6ab6aed3b9fdc9201bb19a307dfc3d9b89891 refactor: pcoinsTip -> CChainState::CoinsTip() (James O'Beirne)

Pull request description:

  This is part of the [assumeutxo project](https://github.com/bitcoin/bitcoin/projects/11):

  Parent PR: #15606
  Issue: #15605
  Specification: https://github.com/jamesob/assumeutxo-docs/tree/2019-04-proposal/proposal

  ---

  This change encapsulates UTXO set data within CChainState instances, removing global data `pcoinsTip` and `pcoinsviewdb`. This is necessary if we want to maintain multiple chainstates with their own rendering of the UTXO set.

  We introduce a class CoinsViews which consolidates the construction of a CCoins* hierarchy.

  This commit could be broken into smaller pieces, but it would require more ephemeral diffs to, e.g., temporarily change CCoinsViewDB's constructor invocations.

ACKs for top commit:
  Sjors:
    reACK 582d2cd74754d6b9a2394616a9c82a89d2d71976
  MarcoFalke:
    ACK 582d2cd747

Tree-SHA512: ec9d904fe5dca8cd2dc4b7916daa5d8bab30856dd4645987300f905e0a19f9919fce4f9d1ff03eda982943ca73e6e9a746be6cf53b46510de36e8c81a1eafba1

3 files changed, 21 insertions, 18 deletions

diff --git a/src/test/miner_tests.cpp b/src/test/miner_tests.cpp
index 05d7f76983..c9661b730d 100644
--- a/src/test/miner_tests.cpp
+++ b/src/test/miner_tests.cpp
@@ -372,7 +372,7 @@ BOOST_AUTO_TEST_CASE(CreateNewBlock_validity)
         CBlockIndex* prev = ::ChainActive().Tip();
         CBlockIndex* next = new CBlockIndex();
         next->phashBlock = new uint256(InsecureRand256());
-        pcoinsTip->SetBestBlock(next->GetBlockHash());
+        ::ChainstateActive().CoinsTip().SetBestBlock(next->GetBlockHash());
         next->pprev = prev;
         next->nHeight = prev->nHeight + 1;
         next->BuildSkip();
@@ -384,7 +384,7 @@ BOOST_AUTO_TEST_CASE(CreateNewBlock_validity)
         CBlockIndex* prev = ::ChainActive().Tip();
         CBlockIndex* next = new CBlockIndex();
         next->phashBlock = new uint256(InsecureRand256());
-        pcoinsTip->SetBestBlock(next->GetBlockHash());
+        ::ChainstateActive().CoinsTip().SetBestBlock(next->GetBlockHash());
         next->pprev = prev;
         next->nHeight = prev->nHeight + 1;
         next->BuildSkip();
@@ -414,7 +414,7 @@ BOOST_AUTO_TEST_CASE(CreateNewBlock_validity)
     while (::ChainActive().Tip()->nHeight > nHeight) {
         CBlockIndex* del = ::ChainActive().Tip();
         ::ChainActive().SetTip(del->pprev);
-        pcoinsTip->SetBestBlock(del->pprev->GetBlockHash());
+        ::ChainstateActive().CoinsTip().SetBestBlock(del->pprev->GetBlockHash());
         delete del->phashBlock;
         delete del;
     }
diff --git a/src/test/setup_common.cpp b/src/test/setup_common.cpp
index de877fd167..0ff081e472 100644
--- a/src/test/setup_common.cpp
+++ b/src/test/setup_common.cpp
@@ -85,8 +85,12 @@ TestingSetup::TestingSetup(const std::string& chainName) : BasicTestingSetup(cha
 
     mempool.setSanityCheck(1.0);
     pblocktree.reset(new CBlockTreeDB(1 << 20, true));
-    pcoinsdbview.reset(new CCoinsViewDB(1 << 23, true));
-    pcoinsTip.reset(new CCoinsViewCache(pcoinsdbview.get()));
+    g_chainstate = MakeUnique<CChainState>();
+    ::ChainstateActive().InitCoinsDB(
+        /* cache_size_bytes */ 1 << 23, /* in_memory */ true, /* should_wipe */ false);
+    assert(!::ChainstateActive().CanFlushToDisk());
+    ::ChainstateActive().InitCoinsCache();
+    assert(::ChainstateActive().CanFlushToDisk());
     if (!LoadGenesisBlock(chainparams)) {
         throw std::runtime_error("LoadGenesisBlock failed.");
     }
@@ -113,8 +117,7 @@ TestingSetup::~TestingSetup()
     g_connman.reset();
     g_banman.reset();
     UnloadBlockIndex();
-    pcoinsTip.reset();
-    pcoinsdbview.reset();
+    g_chainstate.reset();
     pblocktree.reset();
 }
 
diff --git a/src/test/txvalidationcache_tests.cpp b/src/test/txvalidationcache_tests.cpp
index f99a3748c9..e69ebcc2c3 100644
--- a/src/test/txvalidationcache_tests.cpp
+++ b/src/test/txvalidationcache_tests.cpp
@@ -97,7 +97,7 @@ BOOST_FIXTURE_TEST_CASE(tx_mempool_block_doublespend, TestChain100Setup)
     BOOST_CHECK_EQUAL(mempool.size(), 0U);
 }
 
-// Run CheckInputs (using pcoinsTip) on the given transaction, for all script
+// Run CheckInputs (using CoinsTip()) on the given transaction, for all script
 // flags.  Test that CheckInputs passes for all flags that don't overlap with
 // the failing_flags argument, but otherwise fails.
 // CHECKLOCKTIMEVERIFY and CHECKSEQUENCEVERIFY (and future NOP codes that may
@@ -125,7 +125,7 @@ static void ValidateCheckInputsForAllFlags(const CTransaction &tx, uint32_t fail
             // WITNESS requires P2SH
             test_flags |= SCRIPT_VERIFY_P2SH;
         }
-        bool ret = CheckInputs(tx, state, pcoinsTip.get(), true, test_flags, true, add_to_cache, txdata, nullptr);
+        bool ret = CheckInputs(tx, state, &::ChainstateActive().CoinsTip(), true, test_flags, true, add_to_cache, txdata, nullptr);
         // CheckInputs should succeed iff test_flags doesn't intersect with
         // failing_flags
         bool expected_return_value = !(test_flags & failing_flags);
@@ -135,13 +135,13 @@ static void ValidateCheckInputsForAllFlags(const CTransaction &tx, uint32_t fail
         if (ret && add_to_cache) {
             // Check that we get a cache hit if the tx was valid
             std::vector<CScriptCheck> scriptchecks;
-            BOOST_CHECK(CheckInputs(tx, state, pcoinsTip.get(), true, test_flags, true, add_to_cache, txdata, &scriptchecks));
+            BOOST_CHECK(CheckInputs(tx, state, &::ChainstateActive().CoinsTip(), true, test_flags, true, add_to_cache, txdata, &scriptchecks));
             BOOST_CHECK(scriptchecks.empty());
         } else {
             // Check that we get script executions to check, if the transaction
             // was invalid, or we didn't add to cache.
             std::vector<CScriptCheck> scriptchecks;
-            BOOST_CHECK(CheckInputs(tx, state, pcoinsTip.get(), true, test_flags, true, add_to_cache, txdata, &scriptchecks));
+            BOOST_CHECK(CheckInputs(tx, state, &::ChainstateActive().CoinsTip(), true, test_flags, true, add_to_cache, txdata, &scriptchecks));
             BOOST_CHECK_EQUAL(scriptchecks.size(), tx.vin.size());
         }
     }
@@ -204,13 +204,13 @@ BOOST_FIXTURE_TEST_CASE(checkinputs_test, TestChain100Setup)
         CValidationState state;
         PrecomputedTransactionData ptd_spend_tx(spend_tx);
 
-        BOOST_CHECK(!CheckInputs(CTransaction(spend_tx), state, pcoinsTip.get(), true, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_DERSIG, true, true, ptd_spend_tx, nullptr));
+        BOOST_CHECK(!CheckInputs(CTransaction(spend_tx), state, &::ChainstateActive().CoinsTip(), true, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_DERSIG, true, true, ptd_spend_tx, nullptr));
 
         // If we call again asking for scriptchecks (as happens in
         // ConnectBlock), we should add a script check object for this -- we're
         // not caching invalidity (if that changes, delete this test case).
         std::vector<CScriptCheck> scriptchecks;
-        BOOST_CHECK(CheckInputs(CTransaction(spend_tx), state, pcoinsTip.get(), true, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_DERSIG, true, true, ptd_spend_tx, &scriptchecks));
+        BOOST_CHECK(CheckInputs(CTransaction(spend_tx), state, &::ChainstateActive().CoinsTip(), true, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_DERSIG, true, true, ptd_spend_tx, &scriptchecks));
         BOOST_CHECK_EQUAL(scriptchecks.size(), 1U);
 
         // Test that CheckInputs returns true iff DERSIG-enforcing flags are
@@ -227,7 +227,7 @@ BOOST_FIXTURE_TEST_CASE(checkinputs_test, TestChain100Setup)
     block = CreateAndProcessBlock({spend_tx}, p2pk_scriptPubKey);
     LOCK(cs_main);
     BOOST_CHECK(::ChainActive().Tip()->GetBlockHash() == block.GetHash());
-    BOOST_CHECK(pcoinsTip->GetBestBlock() == block.GetHash());
+    BOOST_CHECK(::ChainstateActive().CoinsTip().GetBestBlock() == block.GetHash());
 
     // Test P2SH: construct a transaction that is valid without P2SH, and
     // then test validity with P2SH.
@@ -272,7 +272,7 @@ BOOST_FIXTURE_TEST_CASE(checkinputs_test, TestChain100Setup)
         invalid_with_cltv_tx.vin[0].scriptSig = CScript() << vchSig << 100;
         CValidationState state;
         PrecomputedTransactionData txdata(invalid_with_cltv_tx);
-        BOOST_CHECK(CheckInputs(CTransaction(invalid_with_cltv_tx), state, pcoinsTip.get(), true, SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY, true, true, txdata, nullptr));
+        BOOST_CHECK(CheckInputs(CTransaction(invalid_with_cltv_tx), state, ::ChainstateActive().CoinsTip(), true, SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY, true, true, txdata, nullptr));
     }
 
     // TEST CHECKSEQUENCEVERIFY
@@ -300,7 +300,7 @@ BOOST_FIXTURE_TEST_CASE(checkinputs_test, TestChain100Setup)
         invalid_with_csv_tx.vin[0].scriptSig = CScript() << vchSig << 100;
         CValidationState state;
         PrecomputedTransactionData txdata(invalid_with_csv_tx);
-        BOOST_CHECK(CheckInputs(CTransaction(invalid_with_csv_tx), state, pcoinsTip.get(), true, SCRIPT_VERIFY_CHECKSEQUENCEVERIFY, true, true, txdata, nullptr));
+        BOOST_CHECK(CheckInputs(CTransaction(invalid_with_csv_tx), state, &::ChainstateActive().CoinsTip(), true, SCRIPT_VERIFY_CHECKSEQUENCEVERIFY, true, true, txdata, nullptr));
     }
 
     // TODO: add tests for remaining script flags
@@ -362,12 +362,12 @@ BOOST_FIXTURE_TEST_CASE(checkinputs_test, TestChain100Setup)
         CValidationState state;
         PrecomputedTransactionData txdata(tx);
         // This transaction is now invalid under segwit, because of the second input.
-        BOOST_CHECK(!CheckInputs(CTransaction(tx), state, pcoinsTip.get(), true, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_WITNESS, true, true, txdata, nullptr));
+        BOOST_CHECK(!CheckInputs(CTransaction(tx), state, &::ChainstateActive().CoinsTip(), true, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_WITNESS, true, true, txdata, nullptr));
 
         std::vector<CScriptCheck> scriptchecks;
         // Make sure this transaction was not cached (ie because the first
         // input was valid)
-        BOOST_CHECK(CheckInputs(CTransaction(tx), state, pcoinsTip.get(), true, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_WITNESS, true, true, txdata, &scriptchecks));
+        BOOST_CHECK(CheckInputs(CTransaction(tx), state, &::ChainstateActive().CoinsTip(), true, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_WITNESS, true, true, txdata, &scriptchecks));
         // Should get 2 script checks back -- caching is on a whole-transaction basis.
         BOOST_CHECK_EQUAL(scriptchecks.size(), 2U);
     }