libclang API for comment-to-xml conversion.

The implementation also includes a Relax NG schema and tests for the schema
itself.  The schema is used in c-index-test to verify that XML documents we
produce are valid.  In order to do the validation, we add an optional libxml2
dependency for c-index-test.

Credits for CMake part go to Doug Gregor.  Credits for Autoconf part go to Eric
Christopher.  Thanks!

llvm-svn: 161431

1 files changed, 15 insertions, 0 deletions

diff --git a/clang/include/clang-c/Index.h b/clang/include/clang-c/Index.h
index c725bcfad1c..edd3cbb4a7f 100644
--- a/clang/include/clang-c/Index.h
+++ b/clang/include/clang-c/Index.h
@@ -3687,6 +3687,21 @@ CINDEX_LINKAGE CXString clang_HTMLTagComment_getAsString(CXComment Comment);
 CINDEX_LINKAGE CXString clang_FullComment_getAsHTML(CXComment Comment);
 
 /**
+ * \brief Convert a given full parsed comment to an XML document.
+ *
+ * A Relax NG schema for the XML can be found in comment-xml-schema.rng file
+ * inside clang source tree.
+ *
+ * \param TU the translation unit \c Comment belongs to.
+ *
+ * \param Comment a \c CXComment_FullComment AST node.
+ *
+ * \returns string containing an XML document.
+ */
+CINDEX_LINKAGE CXString clang_FullComment_getAsXML(CXTranslationUnit TU,
+                                                   CXComment Comment);
+
+/**
  * @}
  */