/// <summary>
/// Creates or gets metadata for PE reference.
/// </summary>
/// <remarks>
/// If any of the following exceptions: <see cref="BadImageFormatException"/>, <see cref="FileNotFoundException"/>, <see cref="IOException"/>,
/// are thrown while reading the metadata file, the exception is caught and an appropriate diagnostic stored in <paramref name="diagnostics"/>.
/// </remarks>
private Metadata GetMetadata(PortableExecutableReference peReference, CommonMessageProvider messageProvider, Location location, DiagnosticBag diagnostics)
{
Metadata existingMetadata;
lock (ObservedMetadata)
{
if (TryGetObservedMetadata(peReference, diagnostics, out existingMetadata))
{
return(existingMetadata);
}
}
Metadata newMetadata;
Diagnostic newDiagnostic = null;
try
{
newMetadata = peReference.GetMetadataNoCopy();
// make sure basic structure of the PE image is valid:
var assemblyMetadata = newMetadata as AssemblyMetadata;
if (assemblyMetadata != null)
{
bool dummy = assemblyMetadata.IsValidAssembly();
}
else
{
bool dummy = ((ModuleMetadata)newMetadata).Module.IsLinkedModule;
}
}
catch (Exception e) when(e is BadImageFormatException || e is IOException)
{
newDiagnostic = PortableExecutableReference.ExceptionToDiagnostic(e, messageProvider, location, peReference.Display, peReference.Properties.Kind);
newMetadata = null;
}
lock (ObservedMetadata)
{
if (TryGetObservedMetadata(peReference, diagnostics, out existingMetadata))
{
return(existingMetadata);
}
if (newDiagnostic != null)
{
diagnostics.Add(newDiagnostic);
}
ObservedMetadata.Add(peReference, (MetadataOrDiagnostic)newMetadata ?? newDiagnostic);
return(newMetadata);
}
}
private static AssemblyIdentity TryGetIdentity(MetadataReference metadataReference)
{
PortableExecutableReference peReference = metadataReference as PortableExecutableReference;
if (peReference == null || peReference.Properties.Kind != MetadataImageKind.Assembly)
{
return(null);
}
try
{
return(((AssemblyMetadata)peReference.GetMetadataNoCopy()).GetAssembly().Identity);
}
catch (Exception e) when(e is BadImageFormatException || e is IOException)
{
// ignore, metadata reading errors are reported by the complier for the existing references
return(null);
}
}
