/// <summary>
/// Writes information about metadata references to the pdb so the same
/// reference can be found on sourcelink to create the compilation again
/// </summary>
private void EmbedMetadataReferenceInformation(CommonPEModuleBuilder module)
{
var builder = new BlobBuilder();
// Order of information
// File name (null terminated string): A.exe
// Extern Alias (null terminated string): a1,a2,a3
// MetadataImageKind (byte)
// EmbedInteropTypes (boolean)
// COFF header Timestamp field (4 byte int)
// COFF header SizeOfImage field (4 byte int)
// MVID (Guid, 24 bytes)
foreach (var metadataReference in module.CommonCompilation.ExternalReferences)
{
if (metadataReference is PortableExecutableReference portableReference && portableReference.FilePath is object)
{
var fileName = PathUtilities.GetFileName(portableReference.FilePath);
var reference = module.CommonCompilation.GetAssemblyOrModuleSymbol(portableReference);
var peReader = GetReader(reference);
// Don't write before checking that we can get a peReader for the metadata reference
if (peReader is null)
{
continue;
}
// Write file name first
builder.WriteUTF8(fileName);
// Make sure to add null terminator
builder.WriteByte(0);
// Extern alias
if (portableReference.Properties.Aliases.Any())
{
builder.WriteUTF8(string.Join(",", portableReference.Properties.Aliases));
}
// Always null terminate the extern alias list
builder.WriteByte(0);
byte kindAndEmbedInteropTypes = (byte)(portableReference.Properties.EmbedInteropTypes
? 0b10
: 0b0);
kindAndEmbedInteropTypes |= portableReference.Properties.Kind switch
{
MetadataImageKind.Assembly => 1,
MetadataImageKind.Module => 0,
_ => throw ExceptionUtilities.UnexpectedValue(portableReference.Properties.Kind)
};
builder.WriteByte(kindAndEmbedInteropTypes);
builder.WriteInt32(peReader.PEHeaders.CoffHeader.TimeDateStamp);
builder.WriteInt32(peReader.PEHeaders.PEHeader.SizeOfImage);
var metadataReader = peReader.GetMetadataReader();
var moduleDefinition = metadataReader.GetModuleDefinition();
builder.WriteGuid(metadataReader.GetGuid(moduleDefinition.Mvid));
}
}
_debugMetadataOpt.AddCustomDebugInformation(
parent: EntityHandle.ModuleDefinition,
kind: _debugMetadataOpt.GetOrAddGuid(PortableCustomDebugInfoKinds.CompilationMetadataReferences),
value: _debugMetadataOpt.GetOrAddBlob(builder));