Bitcoin Core  0.19.99
P2P Digital Currency
bloom.h
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1 // Copyright (c) 2012-2019 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 #ifndef BITCOIN_BLOOM_H
6 #define BITCOIN_BLOOM_H
7 
8 #include <serialize.h>
9 
10 #include <vector>
11 
12 class COutPoint;
13 class CTransaction;
14 class uint256;
15 
17 static const unsigned int MAX_BLOOM_FILTER_SIZE = 36000; // bytes
18 static const unsigned int MAX_HASH_FUNCS = 50;
19 
25 {
28  // Only adds outpoints to the filter if the output is a pay-to-pubkey/pay-to-multisig script
31 };
32 
45 {
46 private:
47  std::vector<unsigned char> vData;
48  bool isFull;
49  bool isEmpty;
50  unsigned int nHashFuncs;
51  unsigned int nTweak;
52  unsigned char nFlags;
53 
54  unsigned int Hash(unsigned int nHashNum, const std::vector<unsigned char>& vDataToHash) const;
55 
56 public:
66  CBloomFilter(const unsigned int nElements, const double nFPRate, const unsigned int nTweak, unsigned char nFlagsIn);
67  CBloomFilter() : isFull(true), isEmpty(false), nHashFuncs(0), nTweak(0), nFlags(0) {}
68 
70 
71  template <typename Stream, typename Operation>
72  inline void SerializationOp(Stream& s, Operation ser_action) {
73  READWRITE(vData);
74  READWRITE(nHashFuncs);
75  READWRITE(nTweak);
76  READWRITE(nFlags);
77  }
78 
79  void insert(const std::vector<unsigned char>& vKey);
80  void insert(const COutPoint& outpoint);
81  void insert(const uint256& hash);
82 
83  bool contains(const std::vector<unsigned char>& vKey) const;
84  bool contains(const COutPoint& outpoint) const;
85  bool contains(const uint256& hash) const;
86 
87  void clear();
88  void reset(const unsigned int nNewTweak);
89 
92  bool IsWithinSizeConstraints() const;
93 
95  bool IsRelevantAndUpdate(const CTransaction& tx);
96 
98  void UpdateEmptyFull();
99 };
100 
116 {
117 public:
118  CRollingBloomFilter(const unsigned int nElements, const double nFPRate);
119 
120  void insert(const std::vector<unsigned char>& vKey);
121  void insert(const uint256& hash);
122  bool contains(const std::vector<unsigned char>& vKey) const;
123  bool contains(const uint256& hash) const;
124 
125  void reset();
126 
127 private:
131  std::vector<uint64_t> data;
132  unsigned int nTweak;
134 };
135 
136 #endif // BITCOIN_BLOOM_H
bloomflags
First two bits of nFlags control how much IsRelevantAndUpdate actually updates The remaining bits are...
Definition: bloom.h:24
ADD_SERIALIZE_METHODS
Definition: bloom.h:69
unsigned int nTweak
Definition: bloom.h:51
unsigned char nFlags
Definition: bloom.h:52
bool IsRelevantAndUpdate(const CTransaction &tx)
Also adds any outputs which match the filter to the filter (to match their spending txes) ...
Definition: bloom.cpp:123
BloomFilter is a probabilistic filter which SPV clients provide so that we can filter the transaction...
Definition: bloom.h:44
unsigned int nTweak
Definition: bloom.h:132
bool isFull
Definition: bloom.h:48
RollingBloomFilter is a probabilistic "keep track of most recently inserted" set. ...
Definition: bloom.h:115
static const unsigned int MAX_BLOOM_FILTER_SIZE
20,000 items with fp rate < 0.1% or 10,000 items and <0.0001%
Definition: bloom.h:17
std::vector< unsigned char > vData
Definition: bloom.h:47
unsigned int Hash(unsigned int nHashNum, const std::vector< unsigned char > &vDataToHash) const
Definition: bloom.cpp:42
unsigned int nHashFuncs
Definition: bloom.h:50
void reset(const unsigned int nNewTweak)
Definition: bloom.cpp:112
void insert(const std::vector< unsigned char > &vKey)
Definition: bloom.cpp:48
void clear()
Definition: bloom.cpp:105
CBloomFilter()
Definition: bloom.h:67
static const unsigned int MAX_HASH_FUNCS
Definition: bloom.h:18
An outpoint - a combination of a transaction hash and an index n into its vout.
Definition: transaction.h:18
std::vector< uint64_t > data
Definition: bloom.h:131
256-bit opaque blob.
Definition: uint256.h:120
int nEntriesThisGeneration
Definition: bloom.h:129
void UpdateEmptyFull()
Checks for empty and full filters to avoid wasting cpu.
Definition: bloom.cpp:193
The basic transaction that is broadcasted on the network and contained in blocks. ...
Definition: transaction.h:270
#define READWRITE(...)
Definition: serialize.h:186
void SerializationOp(Stream &s, Operation ser_action)
Definition: bloom.h:72
bool isEmpty
Definition: bloom.h:49
bool IsWithinSizeConstraints() const
True if the size is <= MAX_BLOOM_FILTER_SIZE and the number of hash functions is <= MAX_HASH_FUNCS (c...
Definition: bloom.cpp:118
bool contains(const std::vector< unsigned char > &vKey) const
Definition: bloom.cpp:75
int nEntriesPerGeneration
Definition: bloom.h:128