public static MetadataPRDefinitionStruct* GetProtectedRegionEntryByAddress(uint address, MetadataTypeStruct* exceptionType, MetadataMethodStruct* methodDef)
{
var protectedRegionTable = methodDef->ProtectedRegionTable;
if (protectedRegionTable == null)
return null;
uint method = (uint)methodDef->Method;
if (method == 0)
return null;
uint offset = address - method;
int entries = protectedRegionTable->NumberOfRegions;
int entry = 0;
MetadataPRDefinitionStruct* protectedRegionDef = null;
uint currentStart = uint.MinValue;
uint currentEnd = uint.MaxValue;
while (entry < entries)
{
var prDef = MetadataPRTableStruct.GetProtectedRegionDefinitionAddress(protectedRegionTable, (uint)entry);
uint start = prDef->StartOffset;
uint end = prDef->EndOffset;
if ((offset >= start) && (offset < end) && (start >= currentStart) && (end < currentEnd))
{
var handlerType = prDef->HandlerType;
var exType = prDef->ExceptionType;
// If the handler is a finally clause, accept without testing
// If the handler is a exception clause, accept if the exception type is in the is within the inhertiance chain of the exception object
if ((handlerType == ExceptionHandlerType.Finally) ||
(handlerType == ExceptionHandlerType.Exception && IsTypeInInheritanceChain(exType, exceptionType)))
{
protectedRegionDef = prDef;
currentStart = start;
currentEnd = end;
}
}
entry++;
}
return protectedRegionDef;
}
public static bool IsTypeInInheritanceChain(MetadataTypeStruct* typeDefinition, MetadataTypeStruct* chain)
{
while (chain != null)
{
if (chain == typeDefinition)
return true;
chain = chain->ParentType;
}
return false;
}
public static MetadataMethodStruct* GetMethodDefinitionAddress(MetadataTypeStruct* data, uint slot)
{
return (MetadataMethodStruct*)*((uint*)data + MetadataTypeStruct.MethodsOffset + slot);
}