Introduce serialization and deserialization of diagnostic information

so that CIndex can report diagnostics through the normal mechanisms
even when executing Clang in a separate process. This applies both
when performing code completion and when using ASTs as an intermediary
for clang_createTranslationUnitFromSourceFile().

The serialized format is not perfect at the moment, because it does
not encapsulate macro-instantiation information. Instead, it maps all
source locations back to the instantiation location. However, it does
maintain source-range and fix-it information. To get perfect fidelity
from the serialized format would require serializing a large chunk of
the source manager; at present, it isn't clear if this code will live
long enough for that to matter.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@94740 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 24 insertions, 0 deletions

diff --git a/include/clang/Basic/Diagnostic.h b/include/clang/Basic/Diagnostic.h
index c5d6d7c713..1f7cd07c60 100644
--- a/include/clang/Basic/Diagnostic.h
+++ b/include/clang/Basic/Diagnostic.h
@@ -23,16 +23,19 @@
 
 namespace llvm {
   template <typename T> class SmallVectorImpl;
+  class raw_ostream;
 }
 
 namespace clang {
   class DeclContext;
   class DiagnosticBuilder;
   class DiagnosticClient;
+  class FileManager;
   class IdentifierInfo;
   class LangOptions;
   class PartialDiagnostic;
   class Preprocessor;
+  class SourceManager;
   class SourceRange;
 
   // Import the diagnostic enums themselves.
@@ -400,6 +403,13 @@ public:
   /// \brief Clear out the current diagnostic.
   void Clear() { CurDiagID = ~0U; }
 
+  /// Deserialize - Deserialize the first diagnostic within the memory
+  /// [Memory, MemoryEnd), producing a new diagnostic builder describing the
+  /// deserialized diagnostic. If the memory does not contain a
+  /// diagnostic, returns a diagnostic builder with no diagnostic ID.
+  DiagnosticBuilder Deserialize(FileManager &FM, SourceManager &SM, 
+                                const char *&Memory, const char *MemoryEnd);
+
 private:
   /// getDiagnosticMappingInfo - Return the mapping info currently set for the
   /// specified builtin diagnostic.  This returns the high bit encoding, or zero
@@ -568,6 +578,9 @@ public:
   /// been emitted.
   ~DiagnosticBuilder() { Emit(); }
 
+  /// isActive - Determine whether this diagnostic is still active.
+  bool isActive() const { return DiagObj != 0; }
+
   /// Operator bool: conversion of DiagnosticBuilder to bool always returns
   /// true.  This allows is to be used in boolean error contexts like:
   /// return Diag(...);
@@ -786,6 +799,12 @@ public:
   /// output buffer using the arguments stored in this diagnostic.
   void FormatDiagnostic(const char *DiagStr, const char *DiagEnd,
                         llvm::SmallVectorImpl<char> &OutStr) const;
+
+  /// Serialize - Serialize the given diagnostic (with its diagnostic
+  /// level) to the given stream. Serialization is a lossy operation,
+  /// since the specific diagnostic ID and any macro-instantiation
+  /// information is lost.
+  void Serialize(Diagnostic::Level DiagLevel, llvm::raw_ostream &OS) const;
 };
 
 /// DiagnosticClient - This is an abstract interface implemented by clients of
diff --git a/include/clang/Basic/DiagnosticFrontendKinds.td b/include/clang/Basic/DiagnosticFrontendKinds.td
index 59287b3def..01104fc543 100644
--- a/include/clang/Basic/DiagnosticFrontendKinds.td
+++ b/include/clang/Basic/DiagnosticFrontendKinds.td
@@ -19,6 +19,8 @@ def err_fe_invalid_code_complete_file : Error<
     "cannot locate code-completion file %0">, DefaultFatal;
 def err_fe_stdout_binary : Error<"unable to change standard output to binary">,
   DefaultFatal;
+def err_fe_stderr_binary : Error<"unable to change standard error to binary">,
+  DefaultFatal;
 def err_fe_dependency_file_requires_MT : Error<
     "-dependency-file requires at least one -MT option">;
 def err_fe_incompatible_options : Error<
diff --git a/include/clang/Basic/SourceManager.h b/include/clang/Basic/SourceManager.h
index 59984e7ee8..15ece68510 100644
--- a/include/clang/Basic/SourceManager.h
+++ b/include/clang/Basic/SourceManager.h
@@ -669,6 +669,9 @@ public:
       ::const_iterator fileinfo_iterator;
   fileinfo_iterator fileinfo_begin() const { return FileInfos.begin(); }
   fileinfo_iterator fileinfo_end() const { return FileInfos.end(); }
+  bool hasFileInfo(const FileEntry *File) const {
+    return FileInfos.find(File) != FileInfos.end();
+  }
 
   /// PrintStats - Print statistics to stderr.
   ///