/// <summary>
/// Begins a catch block for the given exception type in the given exception block.
///
/// The given exception block must still be open.
/// </summary>
public CatchBlock BeginCatchBlock(ExceptionBlock forTry, Type exceptionType)
{
if (exceptionType == null)
{
throw new ArgumentNullException("exceptionType");
}
if (forTry == null)
{
throw new ArgumentNullException("forTry");
}
if (((IOwned)forTry).Owner != this)
{
FailOwnership(forTry);
}
if (CurrentExceptionBlock.Count > 0 && forTry != CurrentExceptionBlock.Peek())
{
throw new InvalidOperationException("Cannot start CatchBlock on " + forTry + " while inner ExceptionBlock is still open");
}
if (!typeof(Exception).IsAssignableFrom(exceptionType))
{
throw new ArgumentException("BeginCatchBlock expects a type descending from Exception, found " + exceptionType, "exceptionType");
}
var currentlyOpen = CatchBlocks.Where(c => c.Key.ExceptionBlock == forTry && c.Value.Item2 == -1).Select(s => s.Key).SingleOrDefault();
if (currentlyOpen != null)
{
throw new InvalidOperationException("Cannot start a new catch block, " + currentlyOpen + " has not been ended");
}
if (MustMark)
{
MarkLabel(DefineLabel(AutoNamer.Next(this, "__autolabel")));
}
UpdateState(Wrap(new[] { new StackTransition(0) }, "BeginCatchBlock"));
var tryBlock = TryBlocks[forTry];
if (tryBlock.Item2 != -1)
{
throw new SigilVerificationException("BeginCatchBlock expects an unclosed exception block, but " + forTry + " is already closed", IL.Instructions(AllLocals));
}
IL.BeginCatchBlock(exceptionType);
UpdateState(Wrap(StackTransition.Push(exceptionType), "BeginCatchBlock"));
var ret = new CatchBlock(exceptionType, forTry);
CatchBlocks[ret] = SigilTuple.Create(IL.Index, -1);
return(ret);
}
private void ValidateTryCatchFinallyBranches()
{
foreach (var branch in Branches.AsEnumerable())
{
var instr = BranchPatches[branch.Item3];
var toLabel = branch.Item2;
var fromIndex = branch.Item3;
var toIndex = Marks[toLabel];
var fromTryBlocks = TryBlocks.Where(t => fromIndex >= t.Value.Item1 && fromIndex <= t.Value.Item2).ToList();
var fromCatchBlocks = CatchBlocks.Where(c => fromIndex >= c.Value.Item1 && fromIndex <= c.Value.Item2).ToList();
var fromFinallyBlocks = FinallyBlocks.Where(f => fromIndex >= f.Value.Item1 && fromIndex <= f.Value.Item2).ToList();
var toTryBlocks = TryBlocks.Where(t => toIndex >= t.Value.Item1 && toIndex <= t.Value.Item2).ToList();
var toCatchBlocks = CatchBlocks.Where(c => toIndex >= c.Value.Item1 && toIndex <= c.Value.Item2).ToList();
var toFinallyBlocks = FinallyBlocks.Where(f => toIndex >= f.Value.Item1 && toIndex <= f.Value.Item2).ToList();
var fromTryBlock = fromTryBlocks.OrderByDescending(t => t.Value.Item1).Select(t => t.Key).FirstOrDefault();
var fromCatchBlock = fromCatchBlocks.OrderByDescending(c => c.Value.Item1).Select(c => c.Key).FirstOrDefault();
var fromFinallyBlock = fromFinallyBlocks.OrderByDescending(f => f.Value.Item1).Select(f => f.Key).FirstOrDefault();
var toTryBlock = toTryBlocks.OrderByDescending(t => t.Value.Item1).Select(t => t.Key).FirstOrDefault();
var toCatchBlock = toCatchBlocks.OrderByDescending(c => c.Value.Item1).Select(c => c.Key).FirstOrDefault();
var toFinallyBlock = toFinallyBlocks.OrderByDescending(f => f.Value.Item1).Select(f => f.Key).FirstOrDefault();
// Nothing funky going on, carry on
if (fromTryBlock == null && fromCatchBlock == null && fromFinallyBlock == null && toTryBlock == null && toCatchBlock == null && toFinallyBlock == null)
{
continue;
}
if (fromCatchBlock != null && toCatchBlock != fromCatchBlock)
{
if (instr.Item3 != OpCodes.Leave)
{
throw
new SigilVerificationException(
"Cannot branch from inside " + fromCatchBlock + " to outside, exit the ExceptionBlock first",
IL.Instructions(AllLocals)
);
}
}
if (fromFinallyBlock != null && toFinallyBlock != fromFinallyBlock)
{
throw
new SigilVerificationException(
"Cannot branch from inside " + fromFinallyBlock + " to outside, exit the ExceptionBlock first",
IL.Instructions(AllLocals)
);
}
if (toFinallyBlock != null && fromFinallyBlock != toFinallyBlock)
{
throw
new SigilVerificationException(
"Cannot branch into a FinallyBlock",
IL.Instructions(AllLocals)
);
}
if (fromTryBlock != null && toTryBlock != fromTryBlock)
{
if (instr.Item3 != OpCodes.Leave)
{
throw
new SigilVerificationException(
"Cannot branch from inside " + fromTryBlock + " to outside, exit the ExceptionBlock first",
IL.Instructions(AllLocals)
);
}
}
}
}
