Make appropriate getter-routines "const" in CCoinsView.

Mark the "Get"/"Have" routines in CCoinsView and subclasses as "const".
This commit is contained in:
Daniel Kraft 2014-07-19 16:42:48 +02:00
parent ffb4c210bc
commit a3dc587a62
6 changed files with 66 additions and 48 deletions

View File

@ -52,30 +52,30 @@ bool CCoins::Spend(int nPos) {
}
bool CCoinsView::GetCoins(const uint256 &txid, CCoins &coins) { return false; }
bool CCoinsView::GetCoins(const uint256 &txid, CCoins &coins) const { return false; }
bool CCoinsView::SetCoins(const uint256 &txid, const CCoins &coins) { return false; }
bool CCoinsView::HaveCoins(const uint256 &txid) { return false; }
uint256 CCoinsView::GetBestBlock() { return uint256(0); }
bool CCoinsView::HaveCoins(const uint256 &txid) const { return false; }
uint256 CCoinsView::GetBestBlock() const { return uint256(0); }
bool CCoinsView::SetBestBlock(const uint256 &hashBlock) { return false; }
bool CCoinsView::BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock) { return false; }
bool CCoinsView::GetStats(CCoinsStats &stats) { return false; }
bool CCoinsView::GetStats(CCoinsStats &stats) const { return false; }
CCoinsViewBacked::CCoinsViewBacked(CCoinsView &viewIn) : base(&viewIn) { }
bool CCoinsViewBacked::GetCoins(const uint256 &txid, CCoins &coins) { return base->GetCoins(txid, coins); }
bool CCoinsViewBacked::GetCoins(const uint256 &txid, CCoins &coins) const { return base->GetCoins(txid, coins); }
bool CCoinsViewBacked::SetCoins(const uint256 &txid, const CCoins &coins) { return base->SetCoins(txid, coins); }
bool CCoinsViewBacked::HaveCoins(const uint256 &txid) { return base->HaveCoins(txid); }
uint256 CCoinsViewBacked::GetBestBlock() { return base->GetBestBlock(); }
bool CCoinsViewBacked::HaveCoins(const uint256 &txid) const { return base->HaveCoins(txid); }
uint256 CCoinsViewBacked::GetBestBlock() const { return base->GetBestBlock(); }
bool CCoinsViewBacked::SetBestBlock(const uint256 &hashBlock) { return base->SetBestBlock(hashBlock); }
void CCoinsViewBacked::SetBackend(CCoinsView &viewIn) { base = &viewIn; }
bool CCoinsViewBacked::BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock) { return base->BatchWrite(mapCoins, hashBlock); }
bool CCoinsViewBacked::GetStats(CCoinsStats &stats) { return base->GetStats(stats); }
bool CCoinsViewBacked::GetStats(CCoinsStats &stats) const { return base->GetStats(stats); }
CCoinsKeyHasher::CCoinsKeyHasher() : salt(GetRandHash()) {}
CCoinsViewCache::CCoinsViewCache(CCoinsView &baseIn, bool fDummy) : CCoinsViewBacked(baseIn), hashBlock(0) { }
bool CCoinsViewCache::GetCoins(const uint256 &txid, CCoins &coins) {
bool CCoinsViewCache::GetCoins(const uint256 &txid, CCoins &coins) const {
if (cacheCoins.count(txid)) {
coins = cacheCoins[txid];
return true;
@ -99,19 +99,29 @@ CCoinsMap::iterator CCoinsViewCache::FetchCoins(const uint256 &txid) {
return ret;
}
CCoinsMap::const_iterator CCoinsViewCache::FetchCoins(const uint256 &txid) const {
/* Avoid redundant implementation with the const-cast. */
return const_cast<CCoinsViewCache*>(this)->FetchCoins(txid);
}
CCoins &CCoinsViewCache::GetCoins(const uint256 &txid) {
CCoinsMap::iterator it = FetchCoins(txid);
assert(it != cacheCoins.end());
return it->second;
}
const CCoins &CCoinsViewCache::GetCoins(const uint256 &txid) const {
/* Avoid redundant implementation with the const-cast. */
return const_cast<CCoinsViewCache*>(this)->GetCoins(txid);
}
bool CCoinsViewCache::SetCoins(const uint256 &txid, const CCoins &coins) {
cacheCoins[txid] = coins;
return true;
}
bool CCoinsViewCache::HaveCoins(const uint256 &txid) {
CCoinsMap::iterator it = FetchCoins(txid);
bool CCoinsViewCache::HaveCoins(const uint256 &txid) const {
CCoinsMap::const_iterator it = FetchCoins(txid);
// We're using vtx.empty() instead of IsPruned here for performance reasons,
// as we only care about the case where an transaction was replaced entirely
// in a reorganization (which wipes vout entirely, as opposed to spending
@ -119,7 +129,7 @@ bool CCoinsViewCache::HaveCoins(const uint256 &txid) {
return (it != cacheCoins.end() && !it->second.vout.empty());
}
uint256 CCoinsViewCache::GetBestBlock() {
uint256 CCoinsViewCache::GetBestBlock() const {
if (hashBlock == uint256(0))
hashBlock = base->GetBestBlock();
return hashBlock;
@ -146,18 +156,18 @@ bool CCoinsViewCache::Flush() {
return fOk;
}
unsigned int CCoinsViewCache::GetCacheSize() {
unsigned int CCoinsViewCache::GetCacheSize() const {
return cacheCoins.size();
}
const CTxOut &CCoinsViewCache::GetOutputFor(const CTxIn& input)
const CTxOut &CCoinsViewCache::GetOutputFor(const CTxIn& input) const
{
const CCoins &coins = GetCoins(input.prevout.hash);
assert(coins.IsAvailable(input.prevout.n));
return coins.vout[input.prevout.n];
}
int64_t CCoinsViewCache::GetValueIn(const CTransaction& tx)
int64_t CCoinsViewCache::GetValueIn(const CTransaction& tx) const
{
if (tx.IsCoinBase())
return 0;
@ -169,7 +179,7 @@ int64_t CCoinsViewCache::GetValueIn(const CTransaction& tx)
return nResult;
}
bool CCoinsViewCache::HaveInputs(const CTransaction& tx)
bool CCoinsViewCache::HaveInputs(const CTransaction& tx) const
{
if (!tx.IsCoinBase()) {
// first check whether information about the prevout hash is available
@ -190,7 +200,7 @@ bool CCoinsViewCache::HaveInputs(const CTransaction& tx)
return true;
}
double CCoinsViewCache::GetPriority(const CTransaction &tx, int nHeight)
double CCoinsViewCache::GetPriority(const CTransaction &tx, int nHeight) const
{
if (tx.IsCoinBase())
return 0.0;

View File

@ -276,17 +276,17 @@ class CCoinsView
{
public:
// Retrieve the CCoins (unspent transaction outputs) for a given txid
virtual bool GetCoins(const uint256 &txid, CCoins &coins);
virtual bool GetCoins(const uint256 &txid, CCoins &coins) const;
// Modify the CCoins for a given txid
virtual bool SetCoins(const uint256 &txid, const CCoins &coins);
// Just check whether we have data for a given txid.
// This may (but cannot always) return true for fully spent transactions
virtual bool HaveCoins(const uint256 &txid);
virtual bool HaveCoins(const uint256 &txid) const;
// Retrieve the block hash whose state this CCoinsView currently represents
virtual uint256 GetBestBlock();
virtual uint256 GetBestBlock() const;
// Modify the currently active block hash
virtual bool SetBestBlock(const uint256 &hashBlock);
@ -296,7 +296,7 @@ public:
virtual bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock);
// Calculate statistics about the unspent transaction output set
virtual bool GetStats(CCoinsStats &stats);
virtual bool GetStats(CCoinsStats &stats) const;
// As we use CCoinsViews polymorphically, have a virtual destructor
virtual ~CCoinsView() {}
@ -311,14 +311,14 @@ protected:
public:
CCoinsViewBacked(CCoinsView &viewIn);
bool GetCoins(const uint256 &txid, CCoins &coins);
bool GetCoins(const uint256 &txid, CCoins &coins) const;
bool SetCoins(const uint256 &txid, const CCoins &coins);
bool HaveCoins(const uint256 &txid);
uint256 GetBestBlock();
bool HaveCoins(const uint256 &txid) const;
uint256 GetBestBlock() const;
bool SetBestBlock(const uint256 &hashBlock);
void SetBackend(CCoinsView &viewIn);
bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock);
bool GetStats(CCoinsStats &stats);
bool GetStats(CCoinsStats &stats) const;
};
@ -326,17 +326,20 @@ public:
class CCoinsViewCache : public CCoinsViewBacked
{
protected:
uint256 hashBlock;
CCoinsMap cacheCoins;
/* Make mutable so that we can "fill the cache" even from Get-methods
declared as "const". */
mutable uint256 hashBlock;
mutable CCoinsMap cacheCoins;
public:
CCoinsViewCache(CCoinsView &baseIn, bool fDummy = false);
// Standard CCoinsView methods
bool GetCoins(const uint256 &txid, CCoins &coins);
bool GetCoins(const uint256 &txid, CCoins &coins) const;
bool SetCoins(const uint256 &txid, const CCoins &coins);
bool HaveCoins(const uint256 &txid);
uint256 GetBestBlock();
bool HaveCoins(const uint256 &txid) const;
uint256 GetBestBlock() const;
bool SetBestBlock(const uint256 &hashBlock);
bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock);
@ -344,6 +347,7 @@ public:
// Many methods explicitly require a CCoinsViewCache because of this method, to reduce
// copying.
CCoins &GetCoins(const uint256 &txid);
const CCoins &GetCoins(const uint256 &txid) const;
// Push the modifications applied to this cache to its base.
// Failure to call this method before destruction will cause the changes to be forgotten.
@ -351,7 +355,7 @@ public:
bool Flush();
// Calculate the size of the cache (in number of transactions)
unsigned int GetCacheSize();
unsigned int GetCacheSize() const;
/** Amount of bitcoins coming in to a transaction
Note that lightweight clients may not know anything besides the hash of previous transactions,
@ -360,18 +364,19 @@ public:
@param[in] tx transaction for which we are checking input total
@return Sum of value of all inputs (scriptSigs)
*/
int64_t GetValueIn(const CTransaction& tx);
int64_t GetValueIn(const CTransaction& tx) const;
// Check whether all prevouts of the transaction are present in the UTXO set represented by this view
bool HaveInputs(const CTransaction& tx);
bool HaveInputs(const CTransaction& tx) const;
// Return priority of tx at height nHeight
double GetPriority(const CTransaction &tx, int nHeight);
double GetPriority(const CTransaction &tx, int nHeight) const;
const CTxOut &GetOutputFor(const CTxIn& input);
const CTxOut &GetOutputFor(const CTxIn& input) const;
private:
CCoinsMap::iterator FetchCoins(const uint256 &txid);
CCoinsMap::const_iterator FetchCoins(const uint256 &txid) const;
};
#endif

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@ -27,7 +27,7 @@ void static BatchWriteHashBestChain(CLevelDBBatch &batch, const uint256 &hash) {
CCoinsViewDB::CCoinsViewDB(size_t nCacheSize, bool fMemory, bool fWipe) : db(GetDataDir() / "chainstate", nCacheSize, fMemory, fWipe) {
}
bool CCoinsViewDB::GetCoins(const uint256 &txid, CCoins &coins) {
bool CCoinsViewDB::GetCoins(const uint256 &txid, CCoins &coins) const {
return db.Read(make_pair('c', txid), coins);
}
@ -37,11 +37,11 @@ bool CCoinsViewDB::SetCoins(const uint256 &txid, const CCoins &coins) {
return db.WriteBatch(batch);
}
bool CCoinsViewDB::HaveCoins(const uint256 &txid) {
bool CCoinsViewDB::HaveCoins(const uint256 &txid) const {
return db.Exists(make_pair('c', txid));
}
uint256 CCoinsViewDB::GetBestBlock() {
uint256 CCoinsViewDB::GetBestBlock() const {
uint256 hashBestChain;
if (!db.Read('B', hashBestChain))
return uint256(0);
@ -105,8 +105,11 @@ bool CBlockTreeDB::ReadLastBlockFile(int &nFile) {
return Read('l', nFile);
}
bool CCoinsViewDB::GetStats(CCoinsStats &stats) {
boost::scoped_ptr<leveldb::Iterator> pcursor(db.NewIterator());
bool CCoinsViewDB::GetStats(CCoinsStats &stats) const {
/* It seems that there are no "const iterators" for LevelDB. Since we
only need read operations on it, use a const-cast to get around
that restriction. */
leveldb::Iterator *pcursor = const_cast<CLevelDBWrapper*>(&db)->NewIterator();
pcursor->SeekToFirst();
CHashWriter ss(SER_GETHASH, PROTOCOL_VERSION);

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@ -32,13 +32,13 @@ protected:
public:
CCoinsViewDB(size_t nCacheSize, bool fMemory = false, bool fWipe = false);
bool GetCoins(const uint256 &txid, CCoins &coins);
bool GetCoins(const uint256 &txid, CCoins &coins) const;
bool SetCoins(const uint256 &txid, const CCoins &coins);
bool HaveCoins(const uint256 &txid);
uint256 GetBestBlock();
bool HaveCoins(const uint256 &txid) const;
uint256 GetBestBlock() const;
bool SetBestBlock(const uint256 &hashBlock);
bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock);
bool GetStats(CCoinsStats &stats);
bool GetStats(CCoinsStats &stats) const;
};
/** Access to the block database (blocks/index/) */

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@ -625,7 +625,7 @@ void CTxMemPool::ClearPrioritisation(const uint256 hash)
CCoinsViewMemPool::CCoinsViewMemPool(CCoinsView &baseIn, CTxMemPool &mempoolIn) : CCoinsViewBacked(baseIn), mempool(mempoolIn) { }
bool CCoinsViewMemPool::GetCoins(const uint256 &txid, CCoins &coins) {
bool CCoinsViewMemPool::GetCoins(const uint256 &txid, CCoins &coins) const {
// If an entry in the mempool exists, always return that one, as it's guaranteed to never
// conflict with the underlying cache, and it cannot have pruned entries (as it contains full)
// transactions. First checking the underlying cache risks returning a pruned entry instead.
@ -637,7 +637,7 @@ bool CCoinsViewMemPool::GetCoins(const uint256 &txid, CCoins &coins) {
return (base->GetCoins(txid, coins) && !coins.IsPruned());
}
bool CCoinsViewMemPool::HaveCoins(const uint256 &txid) {
bool CCoinsViewMemPool::HaveCoins(const uint256 &txid) const {
return mempool.exists(txid) || base->HaveCoins(txid);
}

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@ -143,8 +143,8 @@ protected:
public:
CCoinsViewMemPool(CCoinsView &baseIn, CTxMemPool &mempoolIn);
bool GetCoins(const uint256 &txid, CCoins &coins);
bool HaveCoins(const uint256 &txid);
bool GetCoins(const uint256 &txid, CCoins &coins) const;
bool HaveCoins(const uint256 &txid) const;
};
#endif /* BITCOIN_TXMEMPOOL_H */