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

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1// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file. See the AUTHORS file for names of contributors.
4
5#ifndef STORAGE_LEVELDB_DB_DBFORMAT_H_
6#define STORAGE_LEVELDB_DB_DBFORMAT_H_
7
8#include <cstddef>
9#include <cstdint>
10#include <string>
11
12#include "leveldb/comparator.h"
13#include "leveldb/db.h"
14#include "leveldb/filter_policy.h"
15#include "leveldb/slice.h"
16#include "leveldb/table_builder.h"
17#include "util/coding.h"
18#include "util/logging.h"
19
20namespace leveldb {
21
22// Grouping of constants.  We may want to make some of these
23// parameters set via options.
24namespace config {
25static const int kNumLevels = 7;
26
27// Level-0 compaction is started when we hit this many files.
28static const int kL0_CompactionTrigger = 4;
29
30// Soft limit on number of level-0 files.  We slow down writes at this point.
31static const int kL0_SlowdownWritesTrigger = 8;
32
33// Maximum number of level-0 files.  We stop writes at this point.
34static const int kL0_StopWritesTrigger = 12;
35
36// Maximum level to which a new compacted memtable is pushed if it
37// does not create overlap.  We try to push to level 2 to avoid the
38// relatively expensive level 0=>1 compactions and to avoid some
39// expensive manifest file operations.  We do not push all the way to
40// the largest level since that can generate a lot of wasted disk
41// space if the same key space is being repeatedly overwritten.
42static const int kMaxMemCompactLevel = 2;
43
44// Approximate gap in bytes between samples of data read during iteration.
45static const int kReadBytesPeriod = 1048576;
46
47}  // namespace config
48
49class InternalKey;
50
51// Value types encoded as the last component of internal keys.
52// DO NOT CHANGE THESE ENUM VALUES: they are embedded in the on-disk
53// data structures.
54enum ValueType { kTypeDeletion = 0x0, kTypeValue = 0x1 };
55// kValueTypeForSeek defines the ValueType that should be passed when
56// constructing a ParsedInternalKey object for seeking to a particular
57// sequence number (since we sort sequence numbers in decreasing order
58// and the value type is embedded as the low 8 bits in the sequence
59// number in internal keys, we need to use the highest-numbered
60// ValueType, not the lowest).
61static const ValueType kValueTypeForSeek = kTypeValue;
62
63typedef uint64_t SequenceNumber;
64
65// We leave eight bits empty at the bottom so a type and sequence#
66// can be packed together into 64-bits.
67static const SequenceNumber kMaxSequenceNumber = ((0x1ull << 56) - 1);
68
69struct ParsedInternalKey {
70  Slice user_key;
71  SequenceNumber sequence;
72  ValueType type;
73
74  ParsedInternalKey() {}  // Intentionally left uninitialized (for speed)
75  ParsedInternalKey(const Slice& u, const SequenceNumber& seq, ValueType t)
76      : user_key(u), sequence(seq), type(t) {}
77  std::string DebugString() const;
78};
79
80// Return the length of the encoding of "key".
81inline size_t InternalKeyEncodingLength(const ParsedInternalKey& key) {
82  return key.user_key.size() + 8;
83}
84
85// Append the serialization of "key" to *result.
86void AppendInternalKey(std::string* result, const ParsedInternalKey& key);
87
88// Attempt to parse an internal key from "internal_key".  On success,
89// stores the parsed data in "*result", and returns true.
90//
91// On error, returns false, leaves "*result" in an undefined state.
92bool ParseInternalKey(const Slice& internal_key, ParsedInternalKey* result);
93
94// Returns the user key portion of an internal key.
95inline Slice ExtractUserKey(const Slice& internal_key) {
96  assert(internal_key.size() >= 8);
97  return Slice(internal_key.data(), internal_key.size() - 8);
98}
99
100// A comparator for internal keys that uses a specified comparator for
101// the user key portion and breaks ties by decreasing sequence number.
102class InternalKeyComparator : public Comparator {
103 private:
104  const Comparator* user_comparator_;
105
106 public:
107  explicit InternalKeyComparator(const Comparator* c) : user_comparator_(c) {}
108  const char* Name() const override;
109  int Compare(const Slice& a, const Slice& b) const override;
110  void FindShortestSeparator(std::string* start,
111                             const Slice& limit) const override;
112  void FindShortSuccessor(std::string* key) const override;
113
114  const Comparator* user_comparator() const { return user_comparator_; }
115
116  int Compare(const InternalKey& a, const InternalKey& b) const;
117};
118
119// Filter policy wrapper that converts from internal keys to user keys
120class InternalFilterPolicy : public FilterPolicy {
121 private:
122  const FilterPolicy* const user_policy_;
123
124 public:
125  explicit InternalFilterPolicy(const FilterPolicy* p) : user_policy_(p) {}
126  const char* Name() const override;
127  void CreateFilter(const Slice* keys, int n, std::string* dst) const override;
128  bool KeyMayMatch(const Slice& key, const Slice& filter) const override;
129};
130
131// Modules in this directory should keep internal keys wrapped inside
132// the following class instead of plain strings so that we do not
133// incorrectly use string comparisons instead of an InternalKeyComparator.
134class InternalKey {
135 private:
136  std::string rep_;
137
138 public:
139  InternalKey() {}  // Leave rep_ as empty to indicate it is invalid
140  InternalKey(const Slice& user_key, SequenceNumber s, ValueType t) {
141    AppendInternalKey(&rep_, ParsedInternalKey(user_key, s, t));
142  }
143
144  bool DecodeFrom(const Slice& s) {
145    rep_.assign(s.data(), s.size());
146    return !rep_.empty();
147  }
148
149  Slice Encode() const {
150    assert(!rep_.empty());
151    return rep_;
152  }
153
154  Slice user_key() const { return ExtractUserKey(rep_); }
155
156  void SetFrom(const ParsedInternalKey& p) {
157    rep_.clear();
158    AppendInternalKey(&rep_, p);
159  }
160
161  void Clear() { rep_.clear(); }
162
163  std::string DebugString() const;
164};
165
166inline int InternalKeyComparator::Compare(const InternalKey& a,
167                                          const InternalKey& b) const {
168  return Compare(a.Encode(), b.Encode());
169}
170
171inline bool ParseInternalKey(const Slice& internal_key,
172                             ParsedInternalKey* result) {
173  const size_t n = internal_key.size();
174  if (n < 8) return false;
175  uint64_t num = DecodeFixed64(internal_key.data() + n - 8);
176  uint8_t c = num & 0xff;
177  result->sequence = num >> 8;
178  result->type = static_cast<ValueType>(c);
179  result->user_key = Slice(internal_key.data(), n - 8);
180  return (c <= static_cast<uint8_t>(kTypeValue));
181}
182
183// A helper class useful for DBImpl::Get()
184class LookupKey {
185 public:
186  // Initialize *this for looking up user_key at a snapshot with
187  // the specified sequence number.
188  LookupKey(const Slice& user_key, SequenceNumber sequence);
189
190  LookupKey(const LookupKey&) = delete;
191  LookupKey& operator=(const LookupKey&) = delete;
192
193  ~LookupKey();
194
195  // Return a key suitable for lookup in a MemTable.
196  Slice memtable_key() const { return Slice(start_, end_ - start_); }
197
198  // Return an internal key (suitable for passing to an internal iterator)
199  Slice internal_key() const { return Slice(kstart_, end_ - kstart_); }
200
201  // Return the user key
202  Slice user_key() const { return Slice(kstart_, end_ - kstart_ - 8); }
203
204 private:
205  // We construct a char array of the form:
206  //    klength  varint32               <-- start_
207  //    userkey  char[klength]          <-- kstart_
208  //    tag      uint64
209  //                                    <-- end_
210  // The array is a suitable MemTable key.
211  // The suffix starting with "userkey" can be used as an InternalKey.
212  const char* start_;
213  const char* kstart_;
214  const char* end_;
215  char space_[200];  // Avoid allocation for short keys
216};
217
218inline LookupKey::~LookupKey() {
219  if (start_ != space_) delete[] start_;
220}
221
222}  // namespace leveldb
223
224#endif  // STORAGE_LEVELDB_DB_DBFORMAT_H_
225

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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