2 files changed, 45 insertions, 1 deletions
diff --git a/src/pugixml.cpp b/src/pugixml.cpp
index 06bd0ba..4ea08a9 100644
--- a/src/pugixml.cpp
+++ b/src/pugixml.cpp
@@ -203,11 +203,12 @@ namespace pugi
 
 	struct xml_document_struct: public xml_node_struct
 	{
-		xml_document_struct(): xml_node_struct(node_document), allocator(0)
+		xml_document_struct(): xml_node_struct(node_document), allocator(0), buffer(0)
 		{
 		}
 
 		xml_allocator allocator;
+		const char* buffer;
 	};
 
 	xml_document_struct* xml_allocator::allocate_document()
@@ -2620,6 +2621,36 @@ namespace pugi
 		node_output(buffered_writer, *this, indent, flags, depth);
 	}
 
+	int xml_node::offset_debug() const
+	{
+		xml_node_struct* r = root()._root;
+
+		if (!r) return -1;
+
+		const char* buffer = static_cast<xml_document_struct*>(r)->buffer;
+
+		if (!buffer) return -1;
+
+		switch (type())
+		{
+		case node_document:
+			return 0;
+
+		case node_element:
+		case node_declaration:
+			return _root->name_insitu ? _root->name - buffer : -1;
+
+		case node_pcdata:
+		case node_cdata:
+		case node_comment:
+		case node_pi:
+			return _root->value_insitu ? _root->value - buffer : -1;
+
+		default:
+			return -1;
+		}
+	}
+
 #ifdef __BORLANDC__
 	bool operator&&(const xml_node& lhs, bool rhs)
 	{
@@ -2891,6 +2922,9 @@ namespace pugi
 	{
 		destroy();
 
+		// for offset_debug
+		static_cast<xml_document_struct*>(_root)->buffer = xmlstr;
+
 		xml_allocator& alloc = static_cast<xml_document_struct*>(_root)->allocator;
 		
 		xml_parser parser(alloc);
diff --git a/src/pugixml.hpp b/src/pugixml.hpp
index 3e6aa3d..5b9b5c7 100644
--- a/src/pugixml.hpp
+++ b/src/pugixml.hpp
@@ -1210,6 +1210,16 @@ namespace pugi
 		 * \param depth - starting depth (used for indentation)
 		 */
 		void print(xml_writer& writer, const char* indent = "\t", unsigned int flags = format_default, unsigned int depth = 0);
+
+		/**
+		 * Get node offset in parsed file/string (in bytes) for debugging purposes
+		 *
+		 * \return offset in bytes to start of node data, or -1 in case of error
+		 * \note This will return -1 if node information changed to the extent that it's no longer possible to calculate offset, for example
+		 * if element node name has significantly changed; this is guaranteed to return correct offset only for nodes that have not changed
+		 * since parsing.
+		 */
+		int offset_debug() const;
 	};
 
 #ifdef __BORLANDC__