// FIXME it's very dangerous because replacing Id means
// ALL blocks (referenced by MineBlock(), etc.) will be changed.
// we need to add a synchronization mechanism to handle this correctly.
internal void Swap(BlockChain <T> other)
{
// Finds the branch point.
Block <T> topmostCommon = null;
long shorterHeight =
Math.Min(this.LongCount(), other.LongCount()) - 1;
for (
Block <T> t = this[shorterHeight], o = other[shorterHeight];
t.PreviousHash is HashDigest <SHA256> tp &&
o.PreviousHash is HashDigest <SHA256> op;
t = Blocks[tp], o = other.Blocks[op]
)
{
if (t.Equals(o))
{
topmostCommon = t;
break;
}
}
// Unrender stale actions.
for (
Block <T> b = Tip;
!(b is null) && b.Index > (topmostCommon?.Index ?? -1) &&
b.PreviousHash is HashDigest <SHA256> ph;
b = Blocks[ph]
)
{
var actions = b.EvaluateActionsPerTx(a =>
GetStates(new[] { a }, b.PreviousHash).GetValueOrDefault(a)
).Reverse();
foreach (var(_, evaluation) in actions)
{
evaluation.Action.Unrender(
evaluation.InputContext,
evaluation.OutputStates
);
}
}
try
{
_rwlock.EnterWriteLock();
Id = other.Id;
Blocks = new BlockSet <T>(Store);
Transactions = new TransactionSet <T>(Store);
}
finally
{
_rwlock.ExitWriteLock();
}
// Render actions that had been behind.
IEnumerable <Block <T> > blocksToRender =
topmostCommon is Block <T> branchPoint
? this.SkipWhile(b => b.Index <= branchPoint.Index)
: this;
foreach (Block <T> b in blocksToRender)
{
var actions = b.EvaluateActionsPerTx(a =>
GetStates(new[] { a }, b.PreviousHash).GetValueOrDefault(a)
);
foreach (var(_, evaluation) in actions)
{
evaluation.Action.Render(
evaluation.InputContext,
evaluation.OutputStates
);
}
}
}
// FIXME it's very dangerous because replacing Id means
// ALL blocks (referenced by MineBlock(), etc.) will be changed.
// we need to add a synchronization mechanism to handle this correctly.
internal void Swap(BlockChain <T> other, bool render)
{
// Finds the branch point.
Block <T> topmostCommon = null;
if (render && !(Tip is null || other.Tip is null))
{
long shorterHeight =
Math.Min(this.LongCount(), other.LongCount()) - 1;
for (
Block <T> t = this[shorterHeight], o = other[shorterHeight];
t.PreviousHash is HashDigest <SHA256> tp &&
o.PreviousHash is HashDigest <SHA256> op;
t = Blocks[tp], o = other.Blocks[op]
)
{
if (t.Equals(o))
{
topmostCommon = t;
break;
}
}
}
if (render)
{
// Unrender stale actions.
for (
Block <T> b = Tip;
!(b is null) && b.Index > (topmostCommon?.Index ?? -1) &&
b.PreviousHash is HashDigest <SHA256> ph;
b = Blocks[ph]
)
{
List <ActionEvaluation> evaluations = b.EvaluateActionsPerTx(a =>
GetStates(new[] { a }, b.PreviousHash).GetValueOrDefault(a))
.Select(te => te.Item2).ToList();
if (Policy.BlockAction is IAction)
{
evaluations.Add(EvaluateBlockAction(b, evaluations));
}
evaluations.Reverse();
foreach (var evaluation in evaluations)
{
evaluation.Action.Unrender(
evaluation.InputContext,
evaluation.OutputStates
);
}
}
}
try
{
_rwlock.EnterWriteLock();
var tipChangedEventArgs = new TipChangedEventArgs
{
PreviousHash = Tip?.Hash,
PreviousIndex = Tip?.Index,
Hash = other.Tip.Hash,
Index = other.Tip.Index,
};
Guid obsoleteId = Id;
Id = other.Id;
Store.SetCanonicalChainId(Id);
Blocks = new BlockSet <T>(Store);
TipChanged?.Invoke(this, tipChangedEventArgs);
Transactions = new TransactionSet <T>(Store);
Store.DeleteChainId(obsoleteId);
}
finally
{
_rwlock.ExitWriteLock();
}
if (render)
{
// Render actions that had been behind.
IEnumerable <Block <T> > blocksToRender =
topmostCommon is Block <T> branchPoint
? this.SkipWhile(b => b.Index <= branchPoint.Index)
: this;
foreach (Block <T> b in blocksToRender)
{
List <ActionEvaluation> evaluations = b.EvaluateActionsPerTx(a =>
GetStates(new[] { a }, b.PreviousHash).GetValueOrDefault(a))
.Select(te => te.Item2).ToList();
if (Policy.BlockAction is IAction)
{
evaluations.Add(EvaluateBlockAction(b, evaluations));
}
foreach (var evaluation in evaluations)
{
evaluation.Action.Render(
evaluation.InputContext,
evaluation.OutputStates
);
}
}
}
}
// FIXME it's very dangerous because replacing Id means
// ALL blocks (referenced by MineBlock(), etc.) will be changed.
// we need to add a synchronization mechanism to handle this correctly.
internal void Swap(BlockChain <T> other, bool render)
{
_logger.Debug(
"Swaping block chain. (from: {fromChainId}) (to: {toChainId})", Id, other.Id);
// Finds the branch point.
Block <T> topmostCommon = null;
if (render && !(Tip is null || other.Tip is null))
{
long shorterHeight =
Math.Min(LongCount(), other.LongCount()) - 1;
for (
Block <T> t = this[shorterHeight], o = other[shorterHeight];
t.PreviousHash is HashDigest <SHA256> tp &&
o.PreviousHash is HashDigest <SHA256> op;
t = this[tp], o = other[op]
)
{
if (t.Equals(o))
{
topmostCommon = t;
break;
}
}
}
_logger.Debug(
"Branchpoint is {branchPoint} (at {index})", topmostCommon, topmostCommon?.Index);
if (render)
{
_logger.Debug("Unrendering abandoned actions...");
// Unrender stale actions.
for (
Block <T> b = Tip;
!(b is null) && b.Index > (topmostCommon?.Index ?? -1) &&
b.PreviousHash is HashDigest <SHA256> ph;
b = this[ph]
)
{
List <ActionEvaluation> evaluations = b.EvaluateActionsPerTx(a =>
GetState(a, b.PreviousHash).GetValueOrDefault(a))
.Select(te => te.Item2).ToList();
if (Policy.BlockAction is IAction)
{
evaluations.Add(EvaluateBlockAction(b, evaluations));
}
evaluations.Reverse();
foreach (var evaluation in evaluations)
{
_logger.Debug("Unrender action {action}", evaluation.Action);
evaluation.Action.Unrender(
evaluation.InputContext,
evaluation.OutputStates
);
}
}
_logger.Debug($"Unrender for {nameof(Swap)}() is completed.");
}
try
{
_rwlock.EnterWriteLock();
var tipChangedEventArgs = new TipChangedEventArgs
{
PreviousHash = Tip?.Hash,
PreviousIndex = Tip?.Index,
Hash = other.Tip.Hash,
Index = other.Tip.Index,
};
Guid obsoleteId = Id;
Id = other.Id;
Store.SetCanonicalChainId(Id);
_blocks = new BlockSet <T>(Store);
TipChanged?.Invoke(this, tipChangedEventArgs);
_transactions = new TransactionSet <T>(Store);
Store.DeleteChainId(obsoleteId);
}
finally
{
_rwlock.ExitWriteLock();
}
if (render)
{
_logger.Debug("Rendering actions in new chain");
// Render actions that had been behind.
long startToRenderIndex = topmostCommon is Block <T> branchPoint
? branchPoint.Index + 1
: 0;
RenderBlocks(startToRenderIndex);
_logger.Debug($"Render for {nameof(Swap)}() is completed.");
}
}