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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server340 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.

15,441 bytes · SHA-256 3ecd43525a45dbf0… · View upstream ↗

1// Copyright (c) 2012-present 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 <dbwrapper.h>
6
7#include <leveldb/cache.h>
8#include <leveldb/db.h>
9#include <leveldb/env.h>
10#include <leveldb/filter_policy.h>
11#include <leveldb/helpers/memenv/memenv.h>
12#include <leveldb/iterator.h>
13#include <leveldb/options.h>
14#include <leveldb/slice.h>
15#include <leveldb/status.h>
16#include <leveldb/write_batch.h>
17#include <random.h>
18#include <serialize.h>
19#include <span.h>
20#include <streams.h>
21#include <util/byte_units.h>
22#include <util/fs.h>
23#include <util/fs_helpers.h>
24#include <util/log.h>
25#include <util/obfuscation.h>
26#include <util/strencodings.h>
27
28#include <algorithm>
29#include <cassert>
30#include <cstdarg>
31#include <cstdint>
32#include <cstdio>
33#include <memory>
34#include <optional>
35#include <utility>
36
37static auto CharCast(const std::byte* data) { return reinterpret_cast<const char*>(data); }
38
39bool DestroyDB(const std::string& path_str)
40{
41    return leveldb::DestroyDB(path_str, {}).ok();
42}
43
44/** Handle database error by throwing dbwrapper_error exception.
45 */
46static void HandleError(const leveldb::Status& status)
47{
48    if (status.ok())
49        return;
50    const std::string errmsg = "Fatal LevelDB error: " + status.ToString();
51    LogError("%s", errmsg);
52    LogInfo("You can use -debug=leveldb to get more complete diagnostic messages");
53    throw dbwrapper_error(errmsg);
54}
55
56class CBitcoinLevelDBLogger : public leveldb::Logger {
57public:
58    // This code is adapted from posix_logger.h, which is why it is using vsprintf.
59    // Please do not do this in normal code
60    void Logv(const char * format, va_list ap) override {
61            if (!util::log::ShouldDebugLog(BCLog::LEVELDB)) {
62                return;
63            }
64            char buffer[500];
65            for (int iter = 0; iter < 2; iter++) {
66                char* base;
67                int bufsize;
68                if (iter == 0) {
69                    bufsize = sizeof(buffer);
70                    base = buffer;
71                }
72                else {
73                    bufsize = 30000;
74                    base = new char[bufsize];
75                }
76                char* p = base;
77                char* limit = base + bufsize;
78
79                // Print the message
80                if (p < limit) {
81                    va_list backup_ap;
82                    va_copy(backup_ap, ap);
83                    // Do not use vsnprintf elsewhere in bitcoin source code, see above.
84                    p += vsnprintf(p, limit - p, format, backup_ap);
85                    va_end(backup_ap);
86                }
87
88                // Truncate to available space if necessary
89                if (p >= limit) {
90                    if (iter == 0) {
91                        continue;       // Try again with larger buffer
92                    }
93                    else {
94                        p = limit - 1;
95                    }
96                }
97
98                // Add newline if necessary
99                if (p == base || p[-1] != '\n') {
100                    *p++ = '\n';
101                }
102
103                assert(p <= limit);
104                base[std::min(bufsize - 1, (int)(p - base))] = '\0';
105                LogDebug(BCLog::LEVELDB, "%s\n", util::RemoveSuffixView(base, "\n"));
106                if (base != buffer) {
107                    delete[] base;
108                }
109                break;
110            }
111    }
112};
113
114static void SetMaxOpenFiles(leveldb::Options *options) {
115    // On most platforms the default setting of max_open_files (which is 1000)
116    // is optimal. On Windows using a large file count is OK because the handles
117    // do not interfere with select() loops. On 64-bit Unix hosts this value is
118    // also OK, because up to that amount LevelDB will use an mmap
119    // implementation that does not use extra file descriptors (the fds are
120    // closed after being mmap'ed).
121    //
122    // Increasing the value beyond the default is dangerous because LevelDB will
123    // fall back to a non-mmap implementation when the file count is too large.
124    // On 32-bit Unix host we should decrease the value because the handles use
125    // up real fds, and we want to avoid fd exhaustion issues.
126    //
127    // See PR #12495 for further discussion.
128
129    int default_open_files = options->max_open_files;
130#ifndef WIN32
131    if (sizeof(void*) < 8) {
132        options->max_open_files = 64;
133    }
134#endif
135    LogDebug(BCLog::LEVELDB, "LevelDB using max_open_files=%d (default=%d)\n",
136             options->max_open_files, default_open_files);
137}
138
139static leveldb::Options GetOptions(size_t nCacheSize, bool bloom_filter)
140{
141    leveldb::Options options;
142    options.block_cache = leveldb::NewLRUCache(nCacheSize / 2);
143    options.write_buffer_size = nCacheSize / 4; // up to two write buffers may be held in memory simultaneously
144    options.filter_policy = bloom_filter ? leveldb::NewBloomFilterPolicy(10) : nullptr;
145    options.compression = leveldb::kNoCompression;
146    options.info_log = new CBitcoinLevelDBLogger();
147    if (leveldb::kMajorVersion > 1 || (leveldb::kMajorVersion == 1 && leveldb::kMinorVersion >= 16)) {
148        // LevelDB versions before 1.16 consider short writes to be corruption. Only trigger error
149        // on corruption in later versions.
150        options.paranoid_checks = true;
151    }
152    SetMaxOpenFiles(&options);
153    return options;
154}
155
156bool CDBWrapper::HasKeyStartingWith(const fs::path& path, uint8_t prefix)
157{
158    if (!fs::exists(path / "CURRENT")) return false;
159
160    CBitcoinLevelDBLogger logger;
161    leveldb::Options options;
162    options.paranoid_checks = true;
163    // Avoid creating or rotating LevelDB's LOG files during this probe.
164    options.info_log = &logger;
165
166    leveldb::DB* raw_db;
167    HandleError(leveldb::DB::Open(options, fs::PathToString(path), &raw_db));
168    const std::unique_ptr<leveldb::DB> db{raw_db};
169
170    leveldb::ReadOptions iteroptions;
171    iteroptions.verify_checksums = true;
172    iteroptions.fill_cache = false;
173    const std::unique_ptr<leveldb::Iterator> it{db->NewIterator(iteroptions)};
174    const leveldb::Slice prefix_slice{reinterpret_cast<const char*>(&prefix), sizeof(prefix)};
175    it->Seek(prefix_slice);
176    HandleError(it->status());
177    return it->Valid() && it->key().starts_with(prefix_slice);
178}
179
180struct CDBBatch::WriteBatchImpl {
181    leveldb::WriteBatch batch;
182};
183
184CDBBatch::CDBBatch(const CDBWrapper& _parent)
185    : parent{_parent},
186      m_impl_batch{std::make_unique<CDBBatch::WriteBatchImpl>()}
187{
188    m_key_scratch.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
189    m_value_scratch.reserve(DBWRAPPER_PREALLOC_VALUE_SIZE);
190    Clear();
191};
192
193CDBBatch::~CDBBatch() = default;
194
195void CDBBatch::Clear()
196{
197    m_impl_batch->batch.Clear();
198    assert(m_key_scratch.empty());
199    assert(m_value_scratch.empty());
200}
201
202void CDBBatch::WriteImpl(std::span<const std::byte> key, DataStream& value)
203{
204    leveldb::Slice slKey(CharCast(key.data()), key.size());
205    dbwrapper_private::GetObfuscation(parent)(value);
206    leveldb::Slice slValue(CharCast(value.data()), value.size());
207    m_impl_batch->batch.Put(slKey, slValue);
208}
209
210void CDBBatch::EraseImpl(std::span<const std::byte> key)
211{
212    leveldb::Slice slKey(CharCast(key.data()), key.size());
213    m_impl_batch->batch.Delete(slKey);
214}
215
216size_t CDBBatch::ApproximateSize() const
217{
218    return m_impl_batch->batch.ApproximateSize();
219}
220
221struct LevelDBContext {
222    //! custom environment this database is using (may be nullptr in case of default environment)
223    leveldb::Env* penv;
224
225    //! database options used
226    leveldb::Options options;
227
228    //! options used when reading from the database
229    leveldb::ReadOptions readoptions;
230
231    //! options used when iterating over values of the database
232    leveldb::ReadOptions iteroptions;
233
234    //! options used when writing to the database
235    leveldb::WriteOptions writeoptions;
236
237    //! options used when sync writing to the database
238    leveldb::WriteOptions syncoptions;
239
240    //! the database itself
241    leveldb::DB* pdb;
242};
243
244CDBWrapper::CDBWrapper(const DBParams& params)
245    : m_db_context{std::make_unique<LevelDBContext>()}, m_name{fs::PathToString(params.path.stem())}
246{
247    DBContext().penv = nullptr;
248    DBContext().readoptions.verify_checksums = true;
249    DBContext().iteroptions.verify_checksums = true;
250    DBContext().iteroptions.fill_cache = false;

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

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