@ -1,6 +1,6 @@
// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2013 The Bitcoin developers
// Distributed under the MIT/X11 software license, see the accompanying
// Copyright (c) 2009-2014 The Bitcoin developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
# ifndef BITCOIN_COINS_H
@ -17,7 +17,8 @@
# include <boost/foreach.hpp>
# include <boost/unordered_map.hpp>
/** pruned version of CTransaction: only retains metadata and unspent transaction outputs
/**
* Pruned version of CTransaction : only retains metadata and unspent transaction outputs
*
* Serialized format :
* - VARINT ( nVersion )
@ -71,17 +72,17 @@
class CCoins
{
public :
// whether transaction is a coinbase
//! whether transaction is a coinbase
bool fCoinBase ;
// unspent transaction outputs; spent outputs are .IsNull(); spent outputs at the end of the array are dropped
//! unspent transaction outputs; spent outputs are .IsNull(); spent outputs at the end of the array are dropped
std : : vector < CTxOut > vout ;
// at which height this transaction was included in the active block chain
//! at which height this transaction was included in the active block chain
int nHeight ;
// version of the CTransaction; accesses to this value should probably check for nHeight as well,
// as new tx version will probably only be introduced at certain heights
//! version of the CTransaction; accesses to this value should probably check for nHeight as well,
//! as new tx version will probably only be introduced at certain heights
int nVersion ;
void FromTx ( const CTransaction & tx , int nHeightIn ) {
@ -92,7 +93,7 @@ public:
ClearUnspendable ( ) ;
}
// construct a CCoins from a CTransaction, at a given height
//! construct a CCoins from a CTransaction, at a given height
CCoins ( const CTransaction & tx , int nHeightIn ) {
FromTx ( tx , nHeightIn ) ;
}
@ -104,10 +105,10 @@ public:
nVersion = 0 ;
}
// empty constructor
//! empty constructor
CCoins ( ) : fCoinBase ( false ) , vout ( 0 ) , nHeight ( 0 ) , nVersion ( 0 ) { }
// remove spent outputs at the end of vout
//! remove spent outputs at the end of vout
void Cleanup ( ) {
while ( vout . size ( ) > 0 & & vout . back ( ) . IsNull ( ) )
vout . pop_back ( ) ;
@ -130,7 +131,7 @@ public:
std : : swap ( to . nVersion , nVersion ) ;
}
// equality test
//! equality test
friend bool operator = = ( const CCoins & a , const CCoins & b ) {
// Empty CCoins objects are always equal.
if ( a . IsPruned ( ) & & b . IsPruned ( ) )
@ -236,19 +237,19 @@ public:
Cleanup ( ) ;
}
// mark an outpoint spent, and construct undo information
//! mark an outpoint spent, and construct undo information
bool Spend ( const COutPoint & out , CTxInUndo & undo ) ;
// mark a vout spent
//! mark a vout spent
bool Spend ( int nPos ) ;
// check whether a particular output is still available
//! check whether a particular output is still available
bool IsAvailable ( unsigned int nPos ) const {
return ( nPos < vout . size ( ) & & ! vout [ nPos ] . IsNull ( ) ) ;
}
// check whether the entire CCoins is spent
// note that only !IsPruned() CCoins can be serialized
//! check whether the entire CCoins is spent
//! note that only !IsPruned() CCoins can be serialized
bool IsPruned ( ) const {
BOOST_FOREACH ( const CTxOut & out , vout )
if ( ! out . IsNull ( ) )
@ -264,9 +265,12 @@ private:
public :
CCoinsKeyHasher ( ) ;
// This *must* return size_t. With Boost 1.46 on 32-bit systems the
// unordered_map will behave unpredictably if the custom hasher returns a
// uint64_t, resulting in failures when syncing the chain (#4634).
/**
* This * must * return size_t . With Boost 1.46 on 32 - bit systems the
* unordered_map will behave unpredictably if the custom hasher returns a
* uint64_t , resulting in failures when syncing the chain ( # 4634 ) .
*/
size_t operator ( ) ( const uint256 & key ) const {
return key . GetHash ( salt ) ;
}
@ -305,24 +309,24 @@ struct CCoinsStats
class CCoinsView
{
public :
// Retrieve the CCoins (unspent transaction outputs) for a given txid
//! Retrieve the CCoins (unspent transaction outputs) for a given txid
virtual bool GetCoins ( const uint256 & txid , CCoins & coins ) const ;
// Just check whether we have data for a given txid.
// This may (but cannot always) return true for fully spent transactions
//! 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 ) const ;
// Retrieve the block hash whose state this CCoinsView currently represents
//! Retrieve the block hash whose state this CCoinsView currently represents
virtual uint256 GetBestBlock ( ) const ;
// Do a bulk modification (multiple CCoins changes + BestBlock change).
// The passed mapCoins can be modified.
//! Do a bulk modification (multiple CCoins changes + BestBlock change).
//! The passed mapCoins can be modified.
virtual bool BatchWrite ( CCoinsMap & mapCoins , const uint256 & hashBlock ) ;
// Calculate statistics about the unspent transaction output set
//! Calculate statistics about the unspent transaction output set
virtual bool GetStats ( CCoinsStats & stats ) const ;
// As we use CCoinsViews polymorphically, have a virtual destructor
//! As we use CCoinsViews polymorphically, have a virtual destructor
virtual ~ CCoinsView ( ) { }
} ;
@ -346,9 +350,11 @@ public:
class CCoinsViewCache ;
/** A reference to a mutable cache entry. Encapsulating it allows us to run
/**
* A reference to a mutable cache entry . Encapsulating it allows us to run
* cleanup code after the modification is finished , and keeping track of
* concurrent modifications . */
* concurrent modifications .
*/
class CCoinsModifier
{
private :
@ -370,8 +376,10 @@ protected:
/* Whether this cache has an active modifier. */
bool hasModifier ;
/* Make mutable so that we can "fill the cache" even from Get-methods
declared as " const " . */
/**
* Make mutable so that we can " fill the cache " even from Get - methods
* declared as " const " .
*/
mutable uint256 hashBlock ;
mutable CCoinsMap cacheCoins ;
@ -386,37 +394,44 @@ public:
void SetBestBlock ( const uint256 & hashBlock ) ;
bool BatchWrite ( CCoinsMap & mapCoins , const uint256 & hashBlock ) ;
// Return a pointer to CCoins in the cache, or NULL if not found. This is
// more efficient than GetCoins. Modifications to other cache entries are
// allowed while accessing the returned pointer.
/**
* Return a pointer to CCoins in the cache , or NULL if not found . This is
* more efficient than GetCoins . Modifications to other cache entries are
* allowed while accessing the returned pointer .
*/
const CCoins * AccessCoins ( const uint256 & txid ) const ;
// Return a modifiable reference to a CCoins. If no entry with the given
// txid exists, a new one is created. Simultaneous modifications are not
// allowed.
/**
* Return a modifiable reference to a CCoins . If no entry with the given
* txid exists , a new one is created . Simultaneous modifications are not
* allowed .
*/
CCoinsModifier ModifyCoins ( const uint256 & txid ) ;
// Push the modifications applied to this cache to its base.
// Failure to call this method before destruction will cause the changes to be forgotten.
// If false is returned, the state of this cache (and its backing view) will be undefined.
/**
* Push the modifications applied to this cache to its base .
* Failure to call this method before destruction will cause the changes to be forgotten .
* If false is returned , the state of this cache ( and its backing view ) will be undefined .
*/
bool Flush ( ) ;
// Calculate the size of the cache (in number of transactions)
//! Calculate the size of the cache (in number of transactions)
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 ,
so may not be able to calculate this .
@ param [ in ] tx transaction for which we are checking input total
@ return Sum of value of all inputs ( scriptSigs )
/**
* Amount of bitcoins coming in to a transaction
* Note that lightweight clients may not know anything besides the hash of previous transactions ,
* so may not be able to calculate this .
*
* @ param [ in ] tx transaction for which we are checking input total
* @ return Sum of value of all inputs ( scriptSigs )
*/
CAmount GetValueIn ( const CTransaction & tx ) const ;
// Check whether all prevouts of the transaction are present in the UTXO set represented by this view
//! Check whether all prevouts of the transaction are present in the UTXO set represented by this view
bool HaveInputs ( const CTransaction & tx ) const ;
// Return priority of tx at height nHeight
//! Return priority of tx at height nHeight
double GetPriority ( const CTransaction & tx , int nHeight ) const ;
const CTxOut & GetOutputFor ( const CTxIn & input ) const ;
Michael Ford
10 years ago