Merged emitter branch into trunk, changes r105:r151

src/emitterutils.cpp

@@ -0,0 +1,143 @@
+#include "emitterutils.h"
+#include "exp.h"
+#include "indentation.h"
+#include "exceptions.h"
+#include <sstream>
+
+namespace YAML
+{
+	namespace Utils
+	{
+		namespace {
+			bool IsPrintable(char ch) {
+				return (0x20 <= ch && ch <= 0x7E);
+			}
+			
+			bool IsValidPlainScalar(const std::string& str, bool inFlow) {
+				// first check the start
+				const RegEx& start = (inFlow ? Exp::PlainScalarInFlow : Exp::PlainScalar);
+				if(!start.Matches(str))
+					return false;
+				
+				// and check the end for plain whitespace (which can't be faithfully kept in a plain scalar)
+				if(!str.empty() && *str.rbegin() == ' ')
+					return false;
+
+				// then check until something is disallowed
+				const RegEx& disallowed = (inFlow ? Exp::EndScalarInFlow : Exp::EndScalar)
+				                          || (Exp::BlankOrBreak + Exp::Comment)
+				                          || (!Exp::Printable)
+				                          || Exp::Break
+				                          || Exp::Tab;
+				Buffer buffer(&str[0], str.size());
+				while(buffer.size) {
+					if(disallowed.Matches(buffer))
+						return false;
+					++buffer;
+				}
+				
+				return true;
+			}
+		}
+		
+		bool WriteString(ostream& out, const std::string& str, bool inFlow)
+		{
+			if(IsValidPlainScalar(str, inFlow)) {
+				out << str;
+				return true;
+			} else
+				return WriteDoubleQuotedString(out, str);
+		}
+		
+		bool WriteSingleQuotedString(ostream& out, const std::string& str)
+		{
+			out << "'";
+			for(unsigned i=0;i<str.size();i++) {
+				char ch = str[i];
+				if(!IsPrintable(ch))
+					return false;
+				
+				if(ch == '\'')
+					out << "''";
+				else
+					out << ch;
+			}
+			out << "'";
+			return true;
+		}
+		
+		bool WriteDoubleQuotedString(ostream& out, const std::string& str)
+		{
+			out << "\"";
+			for(unsigned i=0;i<str.size();i++) {
+				char ch = str[i];
+				if(IsPrintable(ch)) {
+					if(ch == '\"')
+						out << "\\\"";
+					else if(ch == '\\')
+						out << "\\\\";
+					else
+						out << ch;
+				} else {
+					// TODO: for the common escaped characters, give their usual symbol
+					std::stringstream str;
+					str << "\\x" << std::hex << static_cast <int>(ch);
+					out << str.str();
+				}
+			}
+			out << "\"";
+			return true;
+		}
+
+		bool WriteLiteralString(ostream& out, const std::string& str, int indent)
+		{
+			out << "|\n";
+			out << IndentTo(indent);
+			for(unsigned i=0;i<str.size();i++) {
+				if(str[i] == '\n')
+					out << "\n" << IndentTo(indent);
+				else
+					out << str[i];
+			}
+			return true;
+		}
+		
+		bool WriteComment(ostream& out, const std::string& str, int postCommentIndent)
+		{
+			unsigned curIndent = out.col();
+			out << "#" << Indentation(postCommentIndent);
+			for(unsigned i=0;i<str.size();i++) {
+				if(str[i] == '\n')
+					out << "\n" << IndentTo(curIndent) << "#" << Indentation(postCommentIndent);
+				else
+					out << str[i];
+			}
+			return true;
+		}
+
+		bool WriteAlias(ostream& out, const std::string& str)
+		{
+			out << "*";
+			for(unsigned i=0;i<str.size();i++) {
+				if(!IsPrintable(str[i]) || str[i] == ' ' || str[i] == '\t' || str[i] == '\n' || str[i] == '\r')
+					return false;
+				
+				out << str[i];
+			}
+			return true;
+		}
+		
+		bool WriteAnchor(ostream& out, const std::string& str)
+		{
+			out << "&";
+			for(unsigned i=0;i<str.size();i++) {
+				if(!IsPrintable(str[i]) || str[i] == ' ' || str[i] == '\t' || str[i] == '\n' || str[i] == '\r')
+					return false;
+				
+				out << str[i];
+			}
+			return true;
+		}
+	}
+}
+