C++ CBlockIndex::MintedDenomination方法代码示例

bool GenerateAccumulatorWitness(const PublicCoin &coin, Accumulator& accumulator, AccumulatorWitness& witness, int nSecurityLevel, int& nMintsAdded, string& strError)
{
    uint256 txid;
    if (!zerocoinDB->ReadCoinMint(coin.getValue(), txid)) {
        LogPrint("zero","%s failed to read mint from db\n", __func__);
        return false;
    }

    CTransaction txMinted;
    uint256 hashBlock;
    if (!GetTransaction(txid, txMinted, hashBlock)) {
        LogPrint("zero","%s failed to read tx\n", __func__);
        return false;
    }

    int nHeightMintAdded= mapBlockIndex[hashBlock]->nHeight;
    uint256 nCheckpointBeforeMint = 0;
    CBlockIndex* pindex = chainActive[nHeightMintAdded];
    int nChanges = 0;

    //find the checksum when this was added to the accumulator officially, which will be two checksum changes later
    //reminder that checksums are generated when the block height is a multiple of 10
    while (pindex->nHeight < chainActive.Tip()->nHeight - 1) {
        if (pindex->nHeight == nHeightMintAdded) {
            pindex = chainActive[pindex->nHeight + 1];
            continue;
        }

        //check if the next checksum was generated
        if (pindex->nHeight % 10 == 0) {
            nChanges++;

            if (nChanges == 1) {
                nCheckpointBeforeMint = pindex->nAccumulatorCheckpoint;
                break;
            }
        }
        pindex = chainActive.Next(pindex);
    }

    //the height to start accumulating coins to add to witness
    int nAccStartHeight = nHeightMintAdded - (nHeightMintAdded % 10);

    //If the checkpoint is from the recalculated checkpoint period, then adjust it
    int nHeight_LastGoodCheckpoint = Params().Zerocoin_Block_LastGoodCheckpoint();
    int nHeight_Recalculate = Params().Zerocoin_Block_RecalculateAccumulators();
    if (pindex->nHeight < nHeight_Recalculate - 10 && pindex->nHeight > nHeight_LastGoodCheckpoint) {
        //The checkpoint before the mint will be the last good checkpoint
        nCheckpointBeforeMint = chainActive[nHeight_LastGoodCheckpoint]->nAccumulatorCheckpoint;
        nAccStartHeight = nHeight_LastGoodCheckpoint - 10;
    }

    //Get the accumulator that is right before the cluster of blocks containing our mint was added to the accumulator
    CBigNum bnAccValue = 0;
    if (GetAccumulatorValueFromDB(nCheckpointBeforeMint, coin.getDenomination(), bnAccValue)) {
        if (bnAccValue > 0) {
            accumulator.setValue(bnAccValue);
            witness.resetValue(accumulator, coin);
        }
    }

    //security level: this is an important prevention of tracing the coins via timing. Security level represents how many checkpoints
    //of accumulated coins are added *beyond* the checkpoint that the mint being spent was added too. If each spend added the exact same
    //amounts of checkpoints after the mint was accumulated, then you could know the range of blocks that the mint originated from.
    if (nSecurityLevel < 100) {
        //add some randomness to the user's selection so that it is not always the same
        nSecurityLevel += CBigNum::randBignum(10).getint();

        //security level 100 represents adding all available coins that have been accumulated - user did not select this
        if (nSecurityLevel >= 100)
            nSecurityLevel = 99;
    }

    //add the pubcoins (zerocoinmints that have been published to the chain) up to the next checksum starting from the block
    pindex = chainActive[nAccStartHeight];
    int nChainHeight = chainActive.Height();
    int nHeightStop = nChainHeight % 10;
    nHeightStop = nChainHeight - nHeightStop - 20; // at least two checkpoints deep
    int nCheckpointsAdded = 0;
    nMintsAdded = 0;
    while (pindex->nHeight < nHeightStop + 1) {
        if (pindex->nHeight != nAccStartHeight && pindex->pprev->nAccumulatorCheckpoint != pindex->nAccumulatorCheckpoint)
            ++nCheckpointsAdded;

        //if a new checkpoint was generated on this block, and we have added the specified amount of checkpointed accumulators,
        //then initialize the accumulator at this point and break
        if (!InvalidCheckpointRange(pindex->nHeight) && (pindex->nHeight >= nHeightStop || (nSecurityLevel != 100 && nCheckpointsAdded >= nSecurityLevel))) {
            uint32_t nChecksum = ParseChecksum(chainActive[pindex->nHeight + 10]->nAccumulatorCheckpoint, coin.getDenomination());
            CBigNum bnAccValue = 0;
            if (!zerocoinDB->ReadAccumulatorValue(nChecksum, bnAccValue)) {
                LogPrintf("%s : failed to find checksum in database for accumulator\n", __func__);
                return false;
            }
            accumulator.setValue(bnAccValue);
            break;
        }

        // if this block contains mints of the denomination that is being spent, then add them to the witness
        if (pindex->MintedDenomination(coin.getDenomination())) {
            //grab mints from this block
//.........这里部分代码省略.........