{

// Help messages

private const string Param_TargetCSharpFilePath = "TargetCSharpFilePath";

private const string Param_ReferenceListPath = "ReferenceListPath";

private const string Param_PrintDebugMessage = "-debug";

private const string HelpMessage = @"

// Error messages

private const string TargetSourceDirNotFound = "Cannot find the target source directory. The path '{0}' doesn't exist.";

private const string ReferenceListFileNotFound = "Cannot find the file that contains the reference list. The path '{0}' doesn't exist.";

private const string RefAssemblyNotFound = "Reference assembly '{0}' is declared in the reference list file '{1}', but the assembly doesn't exist.";

private const string UnexpectedFileExtension = "Cannot process '{0}' because its extension is neither '.DLL' nor '.METADATA_DLL'. Please make sure the file is an reference assembly.";

// Format strings for constructing type names

private const string Format_RegularType = "{0}.{1}";

private const string Format_SingleLevelNestedType = "{0}.{1}+{2}";

private const string Format_MultiLevelNestedType = "{0}+{1}";

/*

public static void Main(string[] args)

{

if (args.Length < 2 || args.Length > 3)

{

string message = string.Format(CultureInfo.CurrentCulture, HelpMessage,

Param_TargetCSharpFilePath,

Param_ReferenceListPath,

Param_PrintDebugMessage);

Console.WriteLine(message);

return;

}

bool printDebugMessage = args.Length == 3 && string.Equals(Param_PrintDebugMessage, args[2], StringComparison.OrdinalIgnoreCase);

string targetFilePath = ResolveTargetFilePath(args[0]);

List<string> refAssemblyFiles = ResolveReferenceAssemblies(args[1]);

Dictionary<string, TypeMetadata> typeNameToAssemblyMap = new Dictionary<string, TypeMetadata>(StringComparer.OrdinalIgnoreCase);

// mscorlib.metadata_dll doesn't contain any type definition.

foreach (string filePath in refAssemblyFiles)

{

if (!filePath.EndsWith(".METADATA_DLL", StringComparison.OrdinalIgnoreCase) &&

!filePath.EndsWith(".DLL", StringComparison.OrdinalIgnoreCase))

{

string message = string.Format(CultureInfo.CurrentCulture, UnexpectedFileExtension, filePath);

throw new InvalidOperationException(message);

}

using (Stream stream = File.OpenRead(filePath))

using (PEReader peReader = new PEReader(stream))

{

MetadataReader metadataReader = peReader.GetMetadataReader();

string strongAssemblyName = GetAssemblyStrongName(metadataReader);

foreach (TypeDefinitionHandle typeHandle in metadataReader.TypeDefinitions)

{

// We only care about public types

TypeDefinition typeDefinition = metadataReader.GetTypeDefinition(typeHandle);

// The visibility mask is used to mask out the bits that contain the visibility.

// The visibilities are not combinable, e.g. you can't be both public and private, which is why these aren't independent powers of two.

TypeAttributes visibilityBits = typeDefinition.Attributes & TypeAttributes.VisibilityMask;

if (visibilityBits != TypeAttributes.Public && visibilityBits != TypeAttributes.NestedPublic)

{

continue;

}

string fullName = GetTypeFullName(metadataReader, typeDefinition);

bool isTypeObsolete = IsTypeObsolete(metadataReader, typeDefinition);

if (!typeNameToAssemblyMap.ContainsKey(fullName))

{

// Add unique type.

typeNameToAssemblyMap.Add(fullName, new TypeMetadata(strongAssemblyName, isTypeObsolete));

}

else if (typeNameToAssemblyMap[fullName].IsObsolete && !isTypeObsolete)

{

// Duplicate types found defined in different assemblies, but the previous one is obsolete while the current one is not.

// Replace the existing type with the current one.

if (printDebugMessage)

{

var existingTypeMetadata = typeNameToAssemblyMap[fullName];

Console.WriteLine($@"

}

typeNameToAssemblyMap[fullName] = new TypeMetadata(strongAssemblyName, isTypeObsolete);

}

else if (printDebugMessage)

{

// Duplicate types found defined in different assemblies, and fall into one of the following conditions:

// - both are obsolete

// - both are not obsolete

// - the existing type is not obsolete while the new one is obsolete

var existingTypeMetadata = typeNameToAssemblyMap[fullName];

Console.WriteLine($@"

}

}

}

}

WritePowerShellAssemblyLoadContextPartialClass(targetFilePath, typeNameToAssemblyMap);

}

/// <summary>

/// Check if the type is obsolete.

/// </summary>

private static bool IsTypeObsolete(MetadataReader reader, TypeDefinition typeDefinition)

{

const string obsoleteFullTypeName = "System.ObsoleteAttribute";

foreach (var customAttributeHandle in typeDefinition.GetCustomAttributes())

{

var customAttribute = reader.GetCustomAttribute(customAttributeHandle);

if (IsAttributeOfType(reader, customAttribute, obsoleteFullTypeName))

{

return true;

}

}

return false;

}

/// <summary>

/// Check if the attribute type name is what we expected.

/// </summary>

private static bool IsAttributeOfType(MetadataReader reader, CustomAttribute customAttribute, string expectedTypeName)

{

string attributeFullName = null;

switch (customAttribute.Constructor.Kind)

{

case HandleKind.MethodDefinition:

// Attribute is defined in the same module

MethodDefinition methodDef = reader.GetMethodDefinition((MethodDefinitionHandle)customAttribute.Constructor);

TypeDefinitionHandle declaringTypeDefHandle = methodDef.GetDeclaringType();

if (declaringTypeDefHandle.IsNil)

{

// Global method

return false;

}

TypeDefinition declaringTypeDef = reader.GetTypeDefinition(declaringTypeDefHandle);

attributeFullName = GetTypeFullName(reader, declaringTypeDef);

break;

case HandleKind.MemberReference:

MemberReference memberRef = reader.GetMemberReference((MemberReferenceHandle)customAttribute.Constructor);

switch (memberRef.Parent.Kind)

{

case HandleKind.TypeReference:

TypeReference typeRef = reader.GetTypeReference((TypeReferenceHandle)memberRef.Parent);

attributeFullName = GetTypeFullName(reader, typeRef);

break;

case HandleKind.TypeDefinition:

TypeDefinition typeDef = reader.GetTypeDefinition((TypeDefinitionHandle)memberRef.Parent);

attributeFullName = GetTypeFullName(reader, typeDef);

break;

default:

// constructor is global method, vararg method, or from a generic type.

return false;

}

break;

default:

throw new BadImageFormatException("Invalid custom attribute.");

}

return string.Equals(attributeFullName, expectedTypeName, StringComparison.Ordinal);

}

/// <summary>

/// Get the strong name of a reference assembly represented by the 'metadataReader'

/// </summary>

private static string GetAssemblyStrongName(MetadataReader metadataReader)

{

AssemblyDefinition assemblyDefinition = metadataReader.GetAssemblyDefinition();

string asmName = metadataReader.GetString(assemblyDefinition.Name);

string asmVersion = assemblyDefinition.Version.ToString();

string asmCulture = metadataReader.GetString(assemblyDefinition.Culture);

asmCulture = (asmCulture == string.Empty) ? "neutral" : asmCulture;

AssemblyHashAlgorithm hashAlgorithm = assemblyDefinition.HashAlgorithm;

BlobHandle blobHandle = assemblyDefinition.PublicKey;

BlobReader blobReader = metadataReader.GetBlobReader(blobHandle);

byte[] publickey = blobReader.ReadBytes(blobReader.Length);

HashAlgorithm hashImpl = null;

switch (hashAlgorithm)

{

case AssemblyHashAlgorithm.Sha1:

hashImpl = SHA1.Create();

break;

case AssemblyHashAlgorithm.Sha256:

hashImpl = SHA256.Create();

break;

case AssemblyHashAlgorithm.Sha384:

hashImpl = SHA384.Create();

break;

case AssemblyHashAlgorithm.Sha512:

hashImpl = SHA512.Create();

break;

default:

throw new NotSupportedException();

}

byte[] publicKeyHash = hashImpl.ComputeHash(publickey);

byte[] publicKeyTokenBytes = new byte[8];

// Note that, the low 8 bytes of the hash of public key in reverse order is the public key tokens.

for (int i = 1; i <= 8; i++)

{

publicKeyTokenBytes[i - 1] = publicKeyHash[publicKeyHash.Length - i];

}

// Convert bytes to hex format strings in lower case.

string publicKeyTokenString = Convert.ToHexString(publicKeyTokenBytes).ToLowerInvariant();

string strongAssemblyName = string.Create(CultureInfo.InvariantCulture, $"{asmName}, Version={asmVersion}, Culture={asmCulture}, PublicKeyToken={publicKeyTokenString}");

return strongAssemblyName;

}

/// <summary>

/// Get the full name of a Type reference.

/// </summary>

private static string GetTypeFullName(MetadataReader metadataReader, TypeReference typeReference)

{

string fullName;

string typeName = metadataReader.GetString(typeReference.Name);

string nsName = metadataReader.GetString(typeReference.Namespace);

EntityHandle resolutionScope = typeReference.ResolutionScope;

if (resolutionScope.IsNil || resolutionScope.Kind != HandleKind.TypeReference)

{

fullName = string.Format(CultureInfo.InvariantCulture, Format_RegularType, nsName, typeName);

}

else

{

// It's a nested type.

fullName = typeName;

while (!resolutionScope.IsNil && resolutionScope.Kind == HandleKind.TypeReference)

{

TypeReference declaringTypeRef = metadataReader.GetTypeReference((TypeReferenceHandle)resolutionScope);

resolutionScope = declaringTypeRef.ResolutionScope;

if (resolutionScope.IsNil || resolutionScope.Kind != HandleKind.TypeReference)

{

fullName = string.Format(CultureInfo.InvariantCulture, Format_SingleLevelNestedType,

metadataReader.GetString(declaringTypeRef.Namespace),

metadataReader.GetString(declaringTypeRef.Name),

fullName);

}

else

{

fullName = string.Format(CultureInfo.InvariantCulture, Format_MultiLevelNestedType,

metadataReader.GetString(declaringTypeRef.Name),

fullName);

}

}

}

return fullName;

}

/// <summary>

/// Get the full name of a Type definition.

/// </summary>

private static string GetTypeFullName(MetadataReader metadataReader, TypeDefinition typeDefinition)

{

string fullName;

string typeName = metadataReader.GetString(typeDefinition.Name);

string nsName = metadataReader.GetString(typeDefinition.Namespace);

// Get the enclosing type if the type is nested

TypeDefinitionHandle declaringTypeHandle = typeDefinition.GetDeclaringType();

if (declaringTypeHandle.IsNil)

{

fullName = string.Format(CultureInfo.InvariantCulture, Format_RegularType, nsName, typeName);

}

else

{

fullName = typeName;

while (!declaringTypeHandle.IsNil)

{

TypeDefinition declaringTypeDef = metadataReader.GetTypeDefinition(declaringTypeHandle);

declaringTypeHandle = declaringTypeDef.GetDeclaringType();

if (declaringTypeHandle.IsNil)

{

fullName = string.Format(CultureInfo.InvariantCulture, Format_SingleLevelNestedType,

metadataReader.GetString(declaringTypeDef.Namespace),

metadataReader.GetString(declaringTypeDef.Name),

fullName);

}

else

{

fullName = string.Format(CultureInfo.InvariantCulture, Format_MultiLevelNestedType,

metadataReader.GetString(declaringTypeDef.Name),

fullName);

}

}

}

return fullName;

}

/// <summary>

/// Resolve the target file path.

/// </summary>

private static string ResolveTargetFilePath(string path)

{

if (string.IsNullOrWhiteSpace(path))

{

throw new ArgumentNullException(Param_TargetCSharpFilePath);

}

string targetPath = Path.GetFullPath(path);

string targetParentFolder = Path.GetDirectoryName(targetPath);

if (!Directory.Exists(targetParentFolder))

{

string message = string.Format(CultureInfo.CurrentCulture, TargetSourceDirNotFound, targetParentFolder ?? "null");

throw new ArgumentException(message);

}

return targetPath;

}

/// <summary>

/// Resolve the reference assembly file paths.

/// </summary>

private static List<string> ResolveReferenceAssemblies(string path)

{

if (string.IsNullOrWhiteSpace(path))

{

throw new ArgumentNullException(Param_ReferenceListPath);

}

string referenceListPath = Path.GetFullPath(path);

if (!File.Exists(referenceListPath))

{

string message = string.Format(CultureInfo.CurrentCulture, ReferenceListFileNotFound, referenceListPath ?? "null");

throw new ArgumentException(message);

}

string allText = File.ReadAllText(referenceListPath);

string[] references = allText.Split(';', StringSplitOptions.RemoveEmptyEntries);

List<string> refAssemblyFiles = new List<string>(120);

for (int i = 0; i < references.Length; i++)

{

// Ignore entries that only contain white spaces

if (string.IsNullOrWhiteSpace(references[i]))

{

continue;

}

string refAssemblyPath = references[i].Trim();

if (File.Exists(refAssemblyPath))

{

refAssemblyFiles.Add(refAssemblyPath);

}

else

{

string message = string.Format(CultureInfo.CurrentCulture, RefAssemblyNotFound, refAssemblyPath, referenceListPath);

throw new InvalidDataException(message);

}

}

return refAssemblyFiles;

}

/// <summary>

/// Generate the CSharp source code that initialize the type catalog.

/// </summary>

private static void WritePowerShellAssemblyLoadContextPartialClass(string targetFilePath, Dictionary<string, TypeMetadata> typeNameToAssemblyMap)

{

const string SourceFormat = "{2} {{\"{0}\", \"{1}\"}},";

const string SourceHead = @"//

const string SourceEnd = @"

StringBuilder sourceCode = new StringBuilder(string.Format(CultureInfo.InvariantCulture, SourceHead, typeNameToAssemblyMap.Count));

foreach (KeyValuePair<string, TypeMetadata> pair in typeNameToAssemblyMap)

{

sourceCode.Append(string.Format(CultureInfo.InvariantCulture, SourceFormat, pair.Key, pair.Value.AssemblyName, Environment.NewLine));

}

sourceCode.Append(SourceEnd);

using (FileStream stream = new FileStream(targetFilePath, FileMode.Create, FileAccess.Write))

using (StreamWriter writer = new StreamWriter(stream, Encoding.ASCII))

{

writer.Write(sourceCode.ToString());

}

}

/// <summary>

/// Helper class to keep the metadata of a type.

/// </summary>

private sealed class TypeMetadata

{

internal readonly string AssemblyName;

internal readonly bool IsObsolete;

internal TypeMetadata(string assemblyName, bool isTypeObsolete)

{

this.AssemblyName = assemblyName;

this.IsObsolete = isTypeObsolete;

}

}