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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

Release published 2026-10-28 · Snapshot fetched 2026-11-01. Latest stable release at fetch time; development branches and Git history are excluded. Only the selected code window and visible folders load here.

10,963 bytes · SHA-256 c2a0453fe6894737… · View upstream ↗

1// Copyright (c) The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#include <coins.h>
6#include <kernel/chainstatemanager_opts.h>
7#include <primitives/block.h>
8#include <primitives/transaction.h>
9#include <primitives/transaction_identifier.h>
10#include <txdb.h>
11#include <uint256.h>
12#include <util/byte_units.h>
13#include <util/threadpool.h>
14
15#include <boost/test/unit_test.hpp>
16
17#include <cstdint>
18#include <cstring>
19#include <memory>
20#include <ranges>
21#include <unordered_set>
22#include <vector>
23
24namespace {
25
26std::shared_ptr<ThreadPool> MakeStartedThreadPool()
27{
28    auto pool{std::make_shared<ThreadPool>("fetch_test")};
29    pool->Start(DEFAULT_PREVOUTFETCH_THREADS);
30    return pool;
31}
32
33CBlock CreateBlock() noexcept
34{
35    static constexpr auto NUM_TXS{100};
36    CBlock block;
37    CMutableTransaction coinbase;
38    coinbase.vin.emplace_back();
39    block.vtx.push_back(MakeTransactionRef(coinbase));
40
41    Txid prevhash{Txid::FromUint256(uint256{1})};
42
43    for (const auto i : std::views::iota(1, NUM_TXS)) {
44        CMutableTransaction tx;
45        const Txid txid{i % 20 == 0 ? prevhash : Txid::FromUint256(uint256(i))};
46        tx.vin.emplace_back(txid, 0);
47        prevhash = tx.GetHash();
48        block.vtx.push_back(MakeTransactionRef(tx));
49    }
50
51    return block;
52}
53
54void PopulateView(const CBlock& block, CCoinsView& view, bool spent = false)
55{
56    CCoinsViewCache cache{&view};
57    cache.SetBestBlock(uint256::ONE);
58
59    std::unordered_set<Txid, SaltedCoinsCacheHasher> txids{};
60    txids.reserve(block.vtx.size() - 1);
61    for (const auto& tx : block.vtx | std::views::drop(1)) {
62        for (const auto& in : tx->vin) {
63            if (txids.contains(in.prevout.hash)) continue;
64            Coin coin{};
65            if (!spent) coin.out.nValue = 1;
66            cache.EmplaceCoinInternalDANGER(in.prevout, std::move(coin));
67        }
68        txids.emplace(tx->GetHash());
69    }
70
71    cache.Flush();
72}
73
74void CheckCache(const CBlock& block, const CCoinsViewCache& cache)
75{
76    uint32_t counter{0};
77    std::unordered_set<Txid, SaltedCoinsCacheHasher> txids{};
78    txids.reserve(block.vtx.size() - 1);
79
80    for (const auto& tx : block.vtx) {
81        if (tx->IsCoinBase()) {
82            BOOST_CHECK(!cache.HaveCoinInCache(tx->vin[0].prevout));
83        } else {
84            for (const auto& in : tx->vin) {
85                const auto& outpoint{in.prevout};
86                const auto& first{cache.AccessCoin(outpoint)};
87                const auto& second{cache.AccessCoin(outpoint)};
88                BOOST_CHECK_EQUAL(&first, &second);
89                const auto have{cache.HaveCoinInCache(outpoint)};
90                BOOST_CHECK_NE(txids.contains(outpoint.hash), have);
91                counter += have;
92            }
93            txids.emplace(tx->GetHash());
94        }
95    }
96    BOOST_CHECK_EQUAL(cache.GetCacheSize(), counter);
97}
98
99} // namespace
100
101BOOST_AUTO_TEST_SUITE(coinsviewoverlay_tests)
102
103BOOST_AUTO_TEST_CASE(fetch_inputs_from_db)
104{
105    const auto block{CreateBlock()};
106    CCoinsViewDB db{{.path = "", .cache_bytes = 1_MiB, .memory_only = true}, {}};
107    PopulateView(block, db);
108    CCoinsViewCache main_cache{&db};
109    CoinsViewOverlay view{&main_cache, MakeStartedThreadPool()};
110    const auto reset_guard{view.StartFetching(block)};
111    const auto& outpoint{block.vtx[1]->vin[0].prevout};
112
113    BOOST_CHECK(view.HaveCoin(outpoint));
114    BOOST_CHECK(view.GetCoin(outpoint).has_value());
115    BOOST_CHECK(!main_cache.HaveCoinInCache(outpoint));
116
117    CheckCache(block, view);
118    // Check that no coins have been moved up to main cache from db
119    for (const auto& tx : block.vtx) {
120        for (const auto& in : tx->vin) {
121            BOOST_CHECK(!main_cache.HaveCoinInCache(in.prevout));
122        }
123    }
124
125    view.SetBestBlock(uint256::ONE);
126    BOOST_CHECK(view.SpendCoin(outpoint));
127    view.Flush();
128    BOOST_CHECK(!main_cache.PeekCoin(outpoint).has_value());
129}
130
131BOOST_AUTO_TEST_CASE(fetch_inputs_from_cache)
132{
133    const auto block{CreateBlock()};
134    CCoinsViewDB db{{.path = "", .cache_bytes = 1_MiB, .memory_only = true}, {}};
135    CCoinsViewCache main_cache{&db};
136    PopulateView(block, main_cache);
137    CoinsViewOverlay view{&main_cache, MakeStartedThreadPool()};
138    const auto reset_guard{view.StartFetching(block)};
139    CheckCache(block, view);
140
141    const auto& outpoint{block.vtx[1]->vin[0].prevout};
142    view.SetBestBlock(uint256::ONE);
143    BOOST_CHECK(view.SpendCoin(outpoint));
144    view.Flush();
145    BOOST_CHECK(!main_cache.PeekCoin(outpoint).has_value());
146}
147
148// Test for the case where a block spends coins that are spent in the cache, but
149// the spentness has not been flushed to the db.
150BOOST_AUTO_TEST_CASE(fetch_no_double_spend)
151{
152    const auto block{CreateBlock()};
153    CCoinsViewDB db{{.path = "", .cache_bytes = 1_MiB, .memory_only = true}, {}};
154    PopulateView(block, db);
155    CCoinsViewCache main_cache{&db};
156    // Add all inputs as spent already in cache
157    PopulateView(block, main_cache, /*spent=*/true);
158    CoinsViewOverlay view{&main_cache, MakeStartedThreadPool()};
159    const auto reset_guard{view.StartFetching(block)};
160    for (const auto& tx : block.vtx) {
161        for (const auto& in : tx->vin) {
162            const auto& c{view.AccessCoin(in.prevout)};
163            BOOST_CHECK(c.IsSpent());
164            BOOST_CHECK(!view.HaveCoin(in.prevout));
165            BOOST_CHECK(!view.GetCoin(in.prevout));
166        }
167    }
168    // Coins are not added to the view, even though they exist unspent in the parent db
169    BOOST_CHECK_EQUAL(view.GetCacheSize(), 0);
170}
171
172BOOST_AUTO_TEST_CASE(fetch_no_inputs)
173{
174    const auto block{CreateBlock()};
175    CCoinsViewDB db{{.path = "", .cache_bytes = 1_MiB, .memory_only = true}, {}};
176    CCoinsViewCache main_cache{&db};
177    CoinsViewOverlay view{&main_cache, MakeStartedThreadPool()};
178    const auto reset_guard{view.StartFetching(block)};
179    for (const auto& tx : block.vtx) {
180        for (const auto& in : tx->vin) {
181            const auto& c{view.AccessCoin(in.prevout)};
182            BOOST_CHECK(c.IsSpent());
183            BOOST_CHECK(!view.HaveCoin(in.prevout));
184            BOOST_CHECK(!view.GetCoin(in.prevout));
185        }
186    }
187    BOOST_CHECK_EQUAL(view.GetCacheSize(), 0);
188}
189
190// Access coins that are not block inputs
191BOOST_AUTO_TEST_CASE(access_non_input_coins)
192{
193    CBlock block;
194    CMutableTransaction coinbase;
195    coinbase.vin.emplace_back();
196    block.vtx.push_back(MakeTransactionRef(coinbase));
197    CCoinsViewDB db{{.path = "", .cache_bytes = 1_MiB, .memory_only = true}, {}};
198    CCoinsViewCache main_cache{&db};
199    Coin coin{};
200    coin.out.nValue = 1;
201    const COutPoint outpoint{Txid::FromUint256(uint256::ZERO), 0};
202    main_cache.EmplaceCoinInternalDANGER(COutPoint{outpoint}, std::move(coin));
203
204    CoinsViewOverlay view{&main_cache, MakeStartedThreadPool()};
205    // The block has no non-coinbase transactions, so this fetches nothing and only creates the
206    // reset guard. All lookups below use the fallback path.
207    const auto reset_guard{view.StartFetching(block)};
208
209    // Non-input fallback hit.
210    BOOST_CHECK(!view.AccessCoin(outpoint).IsSpent());
211
212    // Non-input fallback miss.
213    const COutPoint missing_outpoint{Txid::FromUint256(uint256::ONE), 0};
214    BOOST_CHECK(view.AccessCoin(missing_outpoint).IsSpent());
215    BOOST_CHECK(!view.HaveCoinInCache(missing_outpoint));
216}
217
218// Access a fetched input out of order (i.e. not the next one in m_inputs).
219// FetchCoinFromBase must fall back to base->PeekCoin, and the coin must still
220// be inserted into the cache.
221BOOST_AUTO_TEST_CASE(fetch_out_of_order_input_uses_normal_lookup)
222{
223    const auto block{CreateBlock()};
224    CCoinsViewDB db{{.path = "", .cache_bytes = 1_MiB, .memory_only = true}, {}};
225    CCoinsViewCache main_cache{&db};
226    PopulateView(block, main_cache);
227
228    std::vector<COutPoint> fetched_inputs;
229    std::unordered_set<Txid, SaltedCoinsCacheHasher> txids;
230    txids.reserve(block.vtx.size() - 1);
231    for (const auto& tx : block.vtx | std::views::drop(1)) {
232        for (const auto& input : tx->vin) {
233            if (!txids.contains(input.prevout.hash)) fetched_inputs.push_back(input.prevout);
234        }
235        txids.emplace(tx->GetHash());
236    }
237    BOOST_REQUIRE_GE(fetched_inputs.size(), 2U);
238
239    CoinsViewOverlay view{&main_cache, MakeStartedThreadPool()};
240    const auto reset_guard{view.StartFetching(block)};
241
242    const auto& out_of_order_input{fetched_inputs[1]};
243    BOOST_CHECK(!view.HaveCoinInCache(out_of_order_input));
244    BOOST_CHECK(!view.AccessCoin(out_of_order_input).IsSpent());
245    BOOST_CHECK(view.HaveCoinInCache(out_of_order_input));
246
247    CheckCache(block, view);
248}
249
250// The ResetGuard returned by StartFetching must clear all per-block state when

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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