public ChainedHeader FindMaxTotalWork()
{
using (var handle = this.cursorCache.TakeItem())
{
var cursor = handle.Item;
Api.JetSetCurrentIndex(cursor.jetSession, cursor.blockHeadersTableId, "IX_TotalWork");
// IX_TotalWork is in reverse order, so higher total work comes first
if (Api.TryMoveFirst(cursor.jetSession, cursor.blockHeadersTableId))
{
do
{
// check if this block is valid
var valid = Api.RetrieveColumnAsBoolean(cursor.jetSession, cursor.blockHeadersTableId, cursor.blockHeaderValidColumnId);
if (valid == null || valid.Value)
{
// decode chained header with most work and return
var chainedHeader = DataEncoder.DecodeChainedHeader(Api.RetrieveColumn(cursor.jetSession, cursor.blockHeadersTableId, cursor.blockHeaderBytesColumnId));
return(chainedHeader);
}
} while (Api.TryMoveNext(cursor.jetSession, cursor.blockHeadersTableId));
}
// no valid chained header found
return(null);
}
}
public IEnumerable <ChainedHeader> ReadChain()
{
Api.JetSetCurrentIndex(this.jetSession, this.chainTableId, "IX_BlockHeight");
if (Api.TryMoveFirst(this.jetSession, this.chainTableId))
{
do
{
var chainedHeader = DataEncoder.DecodeChainedHeader(Api.RetrieveColumn(this.jetSession, this.chainTableId, this.chainedHeaderBytesColumnId));
yield return(chainedHeader);
} while (Api.TryMoveNext(this.jetSession, this.chainTableId));
}
}
public ChainedHeader GetChainTip()
{
Api.JetSetCurrentIndex(this.jetSession, this.chainTableId, "IX_BlockHeight");
if (Api.TryMoveLast(this.jetSession, this.chainTableId))
{
var chainedHeader = DataEncoder.DecodeChainedHeader(Api.RetrieveColumn(this.jetSession, this.chainTableId, this.chainedHeaderBytesColumnId));
return(chainedHeader);
}
else
{
return(null);
}
}
public IEnumerable <ChainedHeader> ReadChainedHeaders()
{
using (var handle = this.cursorCache.TakeItem())
{
var cursor = handle.Item;
Api.JetSetCurrentIndex(cursor.jetSession, cursor.blockHeadersTableId, null);
if (Api.TryMoveFirst(cursor.jetSession, cursor.blockHeadersTableId))
{
do
{
// decode chained header and return
var chainedHeader = DataEncoder.DecodeChainedHeader(Api.RetrieveColumn(cursor.jetSession, cursor.blockHeadersTableId, cursor.blockHeaderBytesColumnId));
yield return(chainedHeader);
} while (Api.TryMoveNext(cursor.jetSession, cursor.blockHeadersTableId));
}
}
}
public bool TryGetChainedHeader(UInt256 blockHash, out ChainedHeader chainedHeader)
{
using (var handle = this.cursorCache.TakeItem())
{
var cursor = handle.Item;
Api.JetSetCurrentIndex(cursor.jetSession, cursor.blockHeadersTableId, "IX_BlockHash");
Api.MakeKey(cursor.jetSession, cursor.blockHeadersTableId, DbEncoder.EncodeUInt256(blockHash), MakeKeyGrbit.NewKey);
if (Api.TrySeek(cursor.jetSession, cursor.blockHeadersTableId, SeekGrbit.SeekEQ))
{
chainedHeader = DataEncoder.DecodeChainedHeader(Api.RetrieveColumn(cursor.jetSession, cursor.blockHeadersTableId, cursor.blockHeaderBytesColumnId));
return(true);
}
else
{
chainedHeader = default(ChainedHeader);
return(false);
}
}
}
public ChainedHeaderStorage(string baseDirectory)
: base(baseDirectory, "ChainedHeaders",
chainedHeader => DataEncoder.EncodeChainedHeader(chainedHeader),
(blockHash, bytes) => DataEncoder.DecodeChainedHeader(bytes))
{
}
