/// <summary>
/// Decodes PermissionSetAttribute applied in source to determine if it needs any fixup during codegen.
/// </summary>
/// <remarks>
/// PermissionSetAttribute needs fixup when it contains an assignment to the 'File' property as a single named attribute argument.
/// Fixup performed is ported from SecurityAttributes::FixUpPermissionSetAttribute.
/// It involves following steps:
/// 1) Verifying that the specified file name resolves to a valid path.
/// 2) Reading the contents of the file into a byte array.
/// 3) Convert each byte in the file content into two bytes containing hexadecimal characters.
/// 4) Replacing the 'File = fileName' named argument with 'Hex = hexFileContent' argument, where hexFileContent is the converted output from step 3) above.
///
/// Step 1) is performed in this method, i.e. during binding.
/// Remaining steps are performed during serialization as we want to avoid retaining the entire file contents throughout the binding/codegen pass.
/// See <see cref="StarkPlatform.Compiler.CodeGen.PermissionSetAttributeWithFileReference"/> for remaining fixup steps.
/// </remarks>
/// <returns>String containing the resolved file path if PermissionSetAttribute needs fixup during codegen, null otherwise.</returns>
private string DecodePermissionSetAttribute(CSharpCompilation compilation, AttributeSyntax nodeOpt, DiagnosticBag diagnostics)
{
Debug.Assert(!this.HasErrors);
string resolvedFilePath = null;
var namedArgs = this.CommonNamedArguments;
if (namedArgs.Length == 1)
{
var namedArg = namedArgs[0];
NamedTypeSymbol attrType = this.AttributeClass;
string filePropName = PermissionSetAttributeWithFileReference.FilePropertyName;
string hexPropName = PermissionSetAttributeWithFileReference.HexPropertyName;
if (namedArg.Key == filePropName &&
PermissionSetAttributeTypeHasRequiredProperty(attrType, filePropName))
{
// resolve file prop path
var fileName = (string)namedArg.Value.Value;
var resolver = compilation.Options.XmlReferenceResolver;
resolvedFilePath = (resolver != null) ? resolver.ResolveReference(fileName, baseFilePath: null) : null;
if (resolvedFilePath == null)
{
// CS7053: Unable to resolve file path '{0}' specified for the named argument '{1}' for PermissionSet attribute
Location argSyntaxLocation = nodeOpt != null?nodeOpt.GetNamedArgumentSyntax(filePropName).Location : NoLocation.Singleton;
diagnostics.Add(ErrorCode.ERR_PermissionSetAttributeInvalidFile, argSyntaxLocation, fileName ?? "<null>", filePropName);
}
else if (!PermissionSetAttributeTypeHasRequiredProperty(attrType, hexPropName))
{
// PermissionSetAttribute was defined in user source, but doesn't have the required Hex property.
// Native compiler still emits the file content as named assignment to 'Hex' property, but this leads to a runtime exception.
// We instead skip the fixup and emit the file property.
// CONSIDER: We may want to consider taking a breaking change and generating an error here.
return(null);
}
}
}
return(resolvedFilePath);
}