/// <summary> /// Get the import strings for a given method, following forward pointers as necessary. /// </summary> /// <returns> /// For each namespace enclosing the method, a list of import strings, innermost to outermost. /// There should always be at least one entry, for the global namespace. /// </returns> public static ImmutableArray <ImmutableArray <string> > GetCSharpGroupedImportStrings(this ISymUnmanagedReader reader, int methodToken, int methodVersion, out ImmutableArray <string> externAliasStrings) { externAliasStrings = default(ImmutableArray <string>); ImmutableArray <short> groupSizes = default(ImmutableArray <short>); bool seenForward = false; RETRY: byte[] bytes = reader.GetCustomDebugInfoBytes(methodToken, methodVersion); if (bytes == null) { return(default(ImmutableArray <ImmutableArray <string> >)); } foreach (var record in GetCustomDebugInfoRecords(bytes)) { switch (record.Kind) { case CustomDebugInfoKind.UsingInfo: if (!groupSizes.IsDefault) { throw new InvalidOperationException(string.Format("Expected at most one Using record for method {0}", FormatMethodToken(methodToken))); } groupSizes = DecodeUsingRecord(record.Data); break; case CustomDebugInfoKind.ForwardInfo: if (!externAliasStrings.IsDefault) { throw new InvalidOperationException(string.Format("Did not expect both Forward and ForwardToModule records for method {0}", FormatMethodToken(methodToken))); } methodToken = DecodeForwardRecord(record.Data); // Follow at most one forward link (as in FUNCBRECEE::ensureNamespaces). // NOTE: Dev11 may produce chains of forward links (e.g. for System.Collections.Immutable). if (!seenForward) { seenForward = true; goto RETRY; } break; case CustomDebugInfoKind.ForwardToModuleInfo: if (!externAliasStrings.IsDefault) { throw new InvalidOperationException(string.Format("Expected at most one ForwardToModule record for method {0}", FormatMethodToken(methodToken))); } int moduleInfoMethodToken = DecodeForwardToModuleRecord(record.Data); ImmutableArray <string> allModuleInfoImportStrings = reader.GetMethodByVersion(moduleInfoMethodToken, methodVersion).GetImportStrings(); ArrayBuilder <string> externAliasBuilder = ArrayBuilder <string> .GetInstance(); foreach (string importString in allModuleInfoImportStrings) { if (IsCSharpExternAliasInfo(importString)) { externAliasBuilder.Add(importString); } } externAliasStrings = externAliasBuilder.ToImmutableAndFree(); break; } } if (groupSizes.IsDefault) { // This can happen in malformed PDBs (e.g. chains of forwards). return(default(ImmutableArray <ImmutableArray <string> >)); } var method = reader.GetMethodByVersion(methodToken, methodVersion); if (method == null) { return(default(ImmutableArray <ImmutableArray <string> >)); } ImmutableArray <string> importStrings = method.GetImportStrings(); int numImportStrings = importStrings.Length; ArrayBuilder <ImmutableArray <string> > resultBuilder = ArrayBuilder <ImmutableArray <string> > .GetInstance(groupSizes.Length); ArrayBuilder <string> groupBuilder = ArrayBuilder <string> .GetInstance(); int pos = 0; foreach (short groupSize in groupSizes) { for (int i = 0; i < groupSize; i++, pos++) { if (pos >= numImportStrings) { throw new InvalidOperationException(string.Format("Group size indicates more imports than there are import strings (method {0}).", FormatMethodToken(methodToken))); } string importString = importStrings[pos]; if (IsCSharpExternAliasInfo(importString)) { throw new InvalidOperationException(string.Format("Encountered extern alias info before all import strings were consumed (method {0}).", FormatMethodToken(methodToken))); } groupBuilder.Add(importString); } resultBuilder.Add(groupBuilder.ToImmutable()); groupBuilder.Clear(); } if (externAliasStrings.IsDefault) { Debug.Assert(groupBuilder.Count == 0); // Extern alias detail strings (prefix "Z") are not included in the group counts. for (; pos < numImportStrings; pos++) { string importString = importStrings[pos]; if (!IsCSharpExternAliasInfo(importString)) { throw new InvalidOperationException(string.Format("Expected only extern alias info strings after consuming the indicated number of imports (method {0}).", FormatMethodToken(methodToken))); } groupBuilder.Add(importString); } externAliasStrings = groupBuilder.ToImmutableAndFree(); } else { groupBuilder.Free(); if (pos < numImportStrings) { throw new InvalidOperationException(string.Format("Group size indicates fewer imports than there are import strings (method {0}).", FormatMethodToken(methodToken))); } } return(resultBuilder.ToImmutableAndFree()); }