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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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8,952 bytes · SHA-256 8f5dbf61cfff8811… · View upstream ↗

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#include "db/db_iter.h"
6
7#include "db/db_impl.h"
8#include "db/dbformat.h"
9#include "db/filename.h"
10#include "leveldb/env.h"
11#include "leveldb/iterator.h"
12#include "port/port.h"
13#include "util/logging.h"
14#include "util/mutexlock.h"
15#include "util/random.h"
16
17namespace leveldb {
18
19#if 0
20static void DumpInternalIter(Iterator* iter) {
21  for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
22    ParsedInternalKey k;
23    if (!ParseInternalKey(iter->key(), &k)) {
24      fprintf(stderr, "Corrupt '%s'\n", EscapeString(iter->key()).c_str());
25    } else {
26      fprintf(stderr, "@ '%s'\n", k.DebugString().c_str());
27    }
28  }
29}
30#endif
31
32namespace {
33
34// Memtables and sstables that make the DB representation contain
35// (userkey,seq,type) => uservalue entries.  DBIter
36// combines multiple entries for the same userkey found in the DB
37// representation into a single entry while accounting for sequence
38// numbers, deletion markers, overwrites, etc.
39class DBIter : public Iterator {
40 public:
41  // Which direction is the iterator currently moving?
42  // (1) When moving forward, the internal iterator is positioned at
43  //     the exact entry that yields this->key(), this->value()
44  // (2) When moving backwards, the internal iterator is positioned
45  //     just before all entries whose user key == this->key().
46  enum Direction { kForward, kReverse };
47
48  DBIter(DBImpl* db, const Comparator* cmp, Iterator* iter, SequenceNumber s,
49         uint32_t seed)
50      : db_(db),
51        user_comparator_(cmp),
52        iter_(iter),
53        sequence_(s),
54        direction_(kForward),
55        valid_(false),
56        rnd_(seed),
57        bytes_until_read_sampling_(RandomCompactionPeriod()) {}
58
59  DBIter(const DBIter&) = delete;
60  DBIter& operator=(const DBIter&) = delete;
61
62  ~DBIter() override { delete iter_; }
63  bool Valid() const override { return valid_; }
64  Slice key() const override {
65    assert(valid_);
66    return (direction_ == kForward) ? ExtractUserKey(iter_->key()) : saved_key_;
67  }
68  Slice value() const override {
69    assert(valid_);
70    return (direction_ == kForward) ? iter_->value() : saved_value_;
71  }
72  Status status() const override {
73    if (status_.ok()) {
74      return iter_->status();
75    } else {
76      return status_;
77    }
78  }
79
80  void Next() override;
81  void Prev() override;
82  void Seek(const Slice& target) override;
83  void SeekToFirst() override;
84  void SeekToLast() override;
85
86 private:
87  void FindNextUserEntry(bool skipping, std::string* skip);
88  void FindPrevUserEntry();
89  bool ParseKey(ParsedInternalKey* key);
90
91  inline void SaveKey(const Slice& k, std::string* dst) {
92    dst->assign(k.data(), k.size());
93  }
94
95  inline void ClearSavedValue() {
96    if (saved_value_.capacity() > 1048576) {
97      std::string empty;
98      swap(empty, saved_value_);
99    } else {
100      saved_value_.clear();
101    }
102  }
103
104  // Picks the number of bytes that can be read until a compaction is scheduled.
105  size_t RandomCompactionPeriod() {
106    return rnd_.Uniform(2 * config::kReadBytesPeriod);
107  }
108
109  DBImpl* db_;
110  const Comparator* const user_comparator_;
111  Iterator* const iter_;
112  SequenceNumber const sequence_;
113  Status status_;
114  std::string saved_key_;    // == current key when direction_==kReverse
115  std::string saved_value_;  // == current raw value when direction_==kReverse
116  Direction direction_;
117  bool valid_;
118  Random rnd_;
119  size_t bytes_until_read_sampling_;
120};
121
122inline bool DBIter::ParseKey(ParsedInternalKey* ikey) {
123  Slice k = iter_->key();
124
125  size_t bytes_read = k.size() + iter_->value().size();
126  while (bytes_until_read_sampling_ < bytes_read) {
127    bytes_until_read_sampling_ += RandomCompactionPeriod();
128    db_->RecordReadSample(k);
129  }
130  assert(bytes_until_read_sampling_ >= bytes_read);
131  bytes_until_read_sampling_ -= bytes_read;
132
133  if (!ParseInternalKey(k, ikey)) {
134    status_ = Status::Corruption("corrupted internal key in DBIter");
135    return false;
136  } else {
137    return true;
138  }
139}
140
141void DBIter::Next() {
142  assert(valid_);
143
144  if (direction_ == kReverse) {  // Switch directions?
145    direction_ = kForward;
146    // iter_ is pointing just before the entries for this->key(),
147    // so advance into the range of entries for this->key() and then
148    // use the normal skipping code below.
149    if (!iter_->Valid()) {
150      iter_->SeekToFirst();
151    } else {
152      iter_->Next();
153    }
154    if (!iter_->Valid()) {
155      valid_ = false;
156      saved_key_.clear();
157      return;
158    }
159    // saved_key_ already contains the key to skip past.
160  } else {
161    // Store in saved_key_ the current key so we skip it below.
162    SaveKey(ExtractUserKey(iter_->key()), &saved_key_);
163
164    // iter_ is pointing to current key. We can now safely move to the next to
165    // avoid checking current key.
166    iter_->Next();
167    if (!iter_->Valid()) {
168      valid_ = false;
169      saved_key_.clear();
170      return;
171    }
172  }
173
174  FindNextUserEntry(true, &saved_key_);
175}
176
177void DBIter::FindNextUserEntry(bool skipping, std::string* skip) {
178  // Loop until we hit an acceptable entry to yield
179  assert(iter_->Valid());
180  assert(direction_ == kForward);
181  do {
182    ParsedInternalKey ikey;
183    if (ParseKey(&ikey) && ikey.sequence <= sequence_) {
184      switch (ikey.type) {
185        case kTypeDeletion:
186          // Arrange to skip all upcoming entries for this key since
187          // they are hidden by this deletion.
188          SaveKey(ikey.user_key, skip);
189          skipping = true;
190          break;
191        case kTypeValue:
192          if (skipping &&
193              user_comparator_->Compare(ikey.user_key, *skip) <= 0) {
194            // Entry hidden
195          } else {
196            valid_ = true;
197            saved_key_.clear();
198            return;
199          }
200          break;
201      }
202    }
203    iter_->Next();
204  } while (iter_->Valid());
205  saved_key_.clear();
206  valid_ = false;
207}
208
209void DBIter::Prev() {
210  assert(valid_);
211
212  if (direction_ == kForward) {  // Switch directions?
213    // iter_ is pointing at the current entry.  Scan backwards until
214    // the key changes so we can use the normal reverse scanning code.
215    assert(iter_->Valid());  // Otherwise valid_ would have been false
216    SaveKey(ExtractUserKey(iter_->key()), &saved_key_);
217    while (true) {
218      iter_->Prev();
219      if (!iter_->Valid()) {
220        valid_ = false;
221        saved_key_.clear();
222        ClearSavedValue();
223        return;
224      }
225      if (user_comparator_->Compare(ExtractUserKey(iter_->key()), saved_key_) <
226          0) {
227        break;
228      }
229    }
230    direction_ = kReverse;
231  }
232
233  FindPrevUserEntry();
234}
235
236void DBIter::FindPrevUserEntry() {
237  assert(direction_ == kReverse);
238
239  ValueType value_type = kTypeDeletion;
240  if (iter_->Valid()) {
241    do {
242      ParsedInternalKey ikey;
243      if (ParseKey(&ikey) && ikey.sequence <= sequence_) {
244        if ((value_type != kTypeDeletion) &&
245            user_comparator_->Compare(ikey.user_key, saved_key_) < 0) {
246          // We encountered a non-deleted value in entries for previous keys,
247          break;
248        }
249        value_type = ikey.type;
250        if (value_type == kTypeDeletion) {

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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