Report errors in string escape sequences more verbosely

src/ifcparse/IfcCharacterDecoder.cpp

@@ -218,7 +218,7 @@ IfcCharacterDecoder::operator std::string() {
 			(current_char == '\'' && parse_state == APOSTROPHE)
 			) ) {
 				if ( parse_state == APOSTROPHE && current_char != '\'' ) break;
-				throw IfcException("Invalid character encountered");
+				throw IfcInvalidTokenException(file->Tell(), current_char);
 		} else {
 			parse_state = hex = hex_count = 0;
 			// NOTE: this is in fact wrong, this ought to be the representation of the character.
@@ -286,7 +286,7 @@ void IfcCharacterDecoder::dryRun() {
 			(current_char == '\'' && parse_state == APOSTROPHE)
 			) ) {
 				if ( parse_state == APOSTROPHE && current_char != '\'' ) break;
-				throw IfcException("Invalid character encountered");
+				throw IfcInvalidTokenException(file->Tell(), current_char);
 		} else {
 			parse_state = hex_count = 0;
 		}

src/ifcparse/IfcException.h

@@ -67,8 +67,18 @@ namespace IfcParse {
 				" invalid " + expected_type
 			)
 		{}
+		IfcInvalidTokenException(
+			int token_start,
+			char c
+		)
+			: IfcException(
+				std::string("Unexpected '") + std::string(1, c) + "' at " +
+				boost::lexical_cast<std::string>(token_start)
+			)
+		{}
 		~IfcInvalidTokenException() throw () {}
 	};
+
 }
 
 #ifdef _MSC_VER

src/ifcparse/IfcParse.cpp

@@ -1098,8 +1098,15 @@ bool IfcFile::Init(IfcParse::IfcSpfStream* s) {
 			MaxId = (std::max)(MaxId,currentId);
 			currentId = 0;
 		} else {
-			try { token = tokens->Next(); }
-			catch (... ) { token = NoneTokenPtr(); }
+			try {
+				token = tokens->Next();
+			} catch (const IfcException& e) {
+				Logger::Message(Logger::LOG_ERROR, std::string(e.what()) + ". Parsing terminated");
+				token = NoneTokenPtr();
+			} catch (...) {
+				Logger::Message(Logger::LOG_ERROR, "Parsing terminated");
+				token = NoneTokenPtr();
+			}
 		}
 
 		if ( ! (token.startPos || token.lexer) ) break;