BITCOIN MAINNETLive explorer status

Explorer Mempool Feed Forum Visualizer Receipts Tools Learn Code

Inside Bitcoin

Opening the selected file…

₿MyBitcoinExplorer

Bitcoin, in focus.
Explore the network. Understand the connections.

Explore Bitcoin with clarity.

READ THE CODE

Inside Bitcoin

The code behind the network, with room to understand it.

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.

bitcoin / bitcoinstable

Find a file

▤ autocompact_test.cc

▤ fault_injection_test.cc

▤ version_edit_test.cc

▤ version_edit.cc

▤ version_edit.h

▤ version_set_test.cc

▤ version_set.cc

▤ version_set.h

▤ write_batch_internal.h

▤ write_batch_test.cc

▤ arith_uint256.hGuide

▤ bitcoin-chainstate.cpp

▤ bitcoin-cli-res.rc

▤ bitcoin-cli.cppGuide

▤ bitcoin-res.rc

▤ bitcoin-tx-res.rc

▤ bitcoin-tx.cpp

▤ bitcoin-util-res.rc

▤ bitcoin-util.cpp

▤ bitcoin-wallet-res.rc

▤ blockencodings.cppGuide

▤ blockencodings.hGuide

▤ blockfilter.cppGuide

▤ blockfilter.hGuide

▤ chain.cppGuide

▤ chain.h

▤ chainparams.cppGuide

▤ chainparams.hGuide

▤ chainparamsbase.cppGuide

▤ chainparamsbase.hGuide

▤ chainparamsseeds.h

▤ checkqueue.hGuide

▤ clientversion.cppGuide

▤ clientversion.hGuide

▤ cluster_linearize.h

▤ CMakeLists.txt

▤ coins.cppGuide

▤ coins.hGuide

▤ compressor.cppGuide

▤ compressor.hGuide

▤ core_io.cpp

▤ core_io.hGuide

▤ core_memusage.hGuide

▤ cuckoocache.h

▤ dbwrapper.cpp

▤ dbwrapper.hGuide

▤ deploymentinfo.cppGuide

▤ deploymentinfo.hGuide

▤ deploymentstatus.cppGuide

▤ deploymentstatus.hGuide

▤ dummywallet.cppGuide

▤ external_signer.cpp

▤ external_signer.hGuide

▤ merkleblock.cppGuide

▤ merkleblock.hGuide

▤ musig.cpp

▤ musig.hGuide

▤ net_permissions.cppGuide

▤ net_permissions.hGuide

▤ net_processing.cppGuide

▤ netaddress.cppGuide

▤ netmessagemaker.hGuide

▤ noui.cppGuide

▤ noui.hGuide

▤ outputtype.cppGuide

▤ private_broadcast.cpp

▤ private_broadcast.h

▤ semaphore_grant.hGuide

▤ threadsafety.hGuide

▤ tinyformat.h

▤ torcontrol.cppGuide

▤ validation.cppGuide

▤ validation.h

▤ validationinterface.cpp

▤ validationinterface.h

▤ versionbits_impl.hGuide

▤ versionbits.cpp

▤ versionbits.hGuide

▤ walletinitinterface.hGuide

▤ CMakeLists.txtGuide

▤ libbitcoinkernel.pc.in

bitcoin / src / leveldb / db / version_set.cc

Download source ↓

51,207 bytes · SHA-256 c22cd591a0ffa154… · View upstream ↗

751VersionSet::~VersionSet() {
752  current_->Unref();
753  assert(dummy_versions_.next_ == &dummy_versions_);  // List must be empty
754  delete descriptor_log_;
755  delete descriptor_file_;
756}
757
758void VersionSet::AppendVersion(Version* v) {
759  // Make "v" current
760  assert(v->refs_ == 0);
761  assert(v != current_);
762  if (current_ != nullptr) {
763    current_->Unref();
764  }
765  current_ = v;
766  v->Ref();
767
768  // Append to linked list
769  v->prev_ = dummy_versions_.prev_;
770  v->next_ = &dummy_versions_;
771  v->prev_->next_ = v;
772  v->next_->prev_ = v;
773}
774
775Status VersionSet::LogAndApply(VersionEdit* edit, port::Mutex* mu) {
776  if (edit->has_log_number_) {
777    assert(edit->log_number_ >= log_number_);
778    assert(edit->log_number_ < next_file_number_);
779  } else {
780    edit->SetLogNumber(log_number_);
781  }
782
783  if (!edit->has_prev_log_number_) {
784    edit->SetPrevLogNumber(prev_log_number_);
785  }
786
787  edit->SetNextFile(next_file_number_);
788  edit->SetLastSequence(last_sequence_);
789
790  Version* v = new Version(this);
791  {
792    Builder builder(this, current_);
793    builder.Apply(edit);
794    builder.SaveTo(v);
795  }
796  Finalize(v);
797
798  // Initialize new descriptor log file if necessary by creating
799  // a temporary file that contains a snapshot of the current version.
800  std::string new_manifest_file;
801  Status s;
802  if (descriptor_log_ == nullptr) {
803    // No reason to unlock *mu here since we only hit this path in the
804    // first call to LogAndApply (when opening the database).
805    assert(descriptor_file_ == nullptr);
806    new_manifest_file = DescriptorFileName(dbname_, manifest_file_number_);
807    edit->SetNextFile(next_file_number_);
808    s = env_->NewWritableFile(new_manifest_file, &descriptor_file_);
809    if (s.ok()) {
810      descriptor_log_ = new log::Writer(descriptor_file_);
811      s = WriteSnapshot(descriptor_log_);
812    }
813  }
814
815  // Unlock during expensive MANIFEST log write
816  {
817    mu->Unlock();
818
819    // Write new record to MANIFEST log
820    if (s.ok()) {
821      std::string record;
822      edit->EncodeTo(&record);
823      s = descriptor_log_->AddRecord(record);
824      if (s.ok()) {
825        s = descriptor_file_->Sync();
826      }
827      if (!s.ok()) {
828        Log(options_->info_log, "MANIFEST write: %s\n", s.ToString().c_str());
829      }
830    }
831
832    // If we just created a new descriptor file, install it by writing a
833    // new CURRENT file that points to it.
834    if (s.ok() && !new_manifest_file.empty()) {
835      s = SetCurrentFile(env_, dbname_, manifest_file_number_);
836    }
837
838    mu->Lock();
839  }
840
841  // Install the new version
842  if (s.ok()) {
843    AppendVersion(v);
844    log_number_ = edit->log_number_;
845    prev_log_number_ = edit->prev_log_number_;
846  } else {
847    delete v;
848    if (!new_manifest_file.empty()) {
849      delete descriptor_log_;
850      delete descriptor_file_;
851      descriptor_log_ = nullptr;
852      descriptor_file_ = nullptr;
853      env_->DeleteFile(new_manifest_file);
854    }
855  }
856
857  return s;
858}
859
860Status VersionSet::Recover(bool* save_manifest) {
861  struct LogReporter : public log::Reader::Reporter {
862    Status* status;
863    void Corruption(size_t bytes, const Status& s) override {
864      if (this->status->ok()) *this->status = s;
865    }
866  };
867
868  // Read "CURRENT" file, which contains a pointer to the current manifest file
869  std::string current;
870  Status s = ReadFileToString(env_, CurrentFileName(dbname_), &current);
871  if (!s.ok()) {
872    return s;
873  }
874  if (current.empty() || current[current.size() - 1] != '\n') {
875    return Status::Corruption("CURRENT file does not end with newline");
876  }
877  current.resize(current.size() - 1);
878
879  std::string dscname = dbname_ + "/" + current;
880  SequentialFile* file;
881  s = env_->NewSequentialFile(dscname, &file);
882  if (!s.ok()) {
883    if (s.IsNotFound()) {
884      return Status::Corruption("CURRENT points to a non-existent file",
885                                s.ToString());
886    }
887    return s;
888  }
889
890  bool have_log_number = false;
891  bool have_prev_log_number = false;
892  bool have_next_file = false;
893  bool have_last_sequence = false;
894  uint64_t next_file = 0;
895  uint64_t last_sequence = 0;
896  uint64_t log_number = 0;
897  uint64_t prev_log_number = 0;
898  Builder builder(this, current_);
899
900  {
901    LogReporter reporter;
902    reporter.status = &s;
903    log::Reader reader(file, &reporter, true /*checksum*/,
904                       0 /*initial_offset*/);
905    Slice record;
906    std::string scratch;
907    while (reader.ReadRecord(&record, &scratch) && s.ok()) {
908      VersionEdit edit;
909      s = edit.DecodeFrom(record);
910      if (s.ok()) {
911        if (edit.has_comparator_ &&
912            edit.comparator_ != icmp_.user_comparator()->Name()) {
913          s = Status::InvalidArgument(
914              edit.comparator_ + " does not match existing comparator ",
915              icmp_.user_comparator()->Name());
916        }
917      }
918
919      if (s.ok()) {
920        builder.Apply(&edit);
921      }
922
923      if (edit.has_log_number_) {
924        log_number = edit.log_number_;
925        have_log_number = true;
926      }
927
928      if (edit.has_prev_log_number_) {
929        prev_log_number = edit.prev_log_number_;
930        have_prev_log_number = true;
931      }
932
933      if (edit.has_next_file_number_) {
934        next_file = edit.next_file_number_;
935        have_next_file = true;
936      }
937
938      if (edit.has_last_sequence_) {
939        last_sequence = edit.last_sequence_;
940        have_last_sequence = true;
941      }
942    }
943  }
944  delete file;
945  file = nullptr;
946
947  if (s.ok()) {
948    if (!have_next_file) {
949      s = Status::Corruption("no meta-nextfile entry in descriptor");
950    } else if (!have_log_number) {
951      s = Status::Corruption("no meta-lognumber entry in descriptor");
952    } else if (!have_last_sequence) {
953      s = Status::Corruption("no last-sequence-number entry in descriptor");
954    }
955
956    if (!have_prev_log_number) {
957      prev_log_number = 0;
958    }
959
960    MarkFileNumberUsed(prev_log_number);
961    MarkFileNumberUsed(log_number);
962  }
963
964  if (s.ok()) {
965    Version* v = new Version(this);
966    builder.SaveTo(v);
967    // Install recovered version
968    Finalize(v);
969    AppendVersion(v);
970    manifest_file_number_ = next_file;
971    next_file_number_ = next_file + 1;
972    last_sequence_ = last_sequence;
973    log_number_ = log_number;
974    prev_log_number_ = prev_log_number;
975
976    // See if we can reuse the existing MANIFEST file.
977    if (ReuseManifest(dscname, current)) {
978      // No need to save new manifest
979    } else {
980      *save_manifest = true;
981    }
982  }
983
984  return s;
985}
986
987bool VersionSet::ReuseManifest(const std::string& dscname,
988                               const std::string& dscbase) {
989  if (!options_->reuse_logs) {
990    return false;
991  }
992  FileType manifest_type;
993  uint64_t manifest_number;
994  uint64_t manifest_size = 0;
995  if (!ParseFileName(dscbase, &manifest_number, &manifest_type) ||
996      manifest_type != kDescriptorFile ||
997      !env_->GetFileSize(dscname, &manifest_size).ok() ||
998      // Make new compacted MANIFEST if old one is too big
999      manifest_size >= TargetFileSize(options_)) {
1000    return false;

A READING COMPANION

Source available. Guide coming next.

This file is included in the stable source snapshot. A file-specific guide has not been published yet.

440 guided files · 2,580 pending. Guides cover key sections, not every line.

cmake/bitcoin-build-config.h.in src/consensus/amount.h src/consensus/consensus.h src/primitives/block.h src/primitives/transaction.h src/crypto/sha256.h src/util/moneystr.h src/clientversion.h src/uint256.h src/script/script.h src/policy/policy.h CMakeLists.txt README.md COPYING src/consensus/tx_check.cpp src/consensus/tx_verify.cpp src/consensus/merkle.cpp src/pow.cpp src/validation.cpp src/script/interpreter.cpp src/script/solver.cpp src/script/sign.cpp src/key_io.cpp src/net.cpp src/net_processing.cpp src/netaddress.cpp src/protocol.h src/wallet/wallet.cpp src/wallet/spend.cpp

← Previous 250 linesCode page 4Next 250 lines →

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

Independent explanations by MyBitcoinExplorer. Not affiliated with or endorsed by Bitcoin Core. Guides are educational and do not replace the source or its tests.

Bitcoin Core source © its contributors, distributed under the MIT license. Original notices and bundled third-party licenses are retained in the source tree.