Changed: Implement escapeArgument function

--HG--
branch : develop

code/nel/include/nel/misc/common.h

@@ -394,6 +394,9 @@ std::string expandEnvironmentVariables(const std::string &s);
 bool explodeArguments(const std::string &str, std::vector<std::string> &args);
 std::string joinArguments(const std::vector<std::string> &args);
 
+/// Escape an argument to not evaluate environment variables or special cases
+std::string escapeArgument(const std::string &arg);
+
 /// This function kills a program using his pid (on unix, it uses the kill() POSIX function)
 bool killProgram(uint32 pid);
 

code/nel/src/misc/common.cpp

@@ -1247,6 +1247,41 @@ std::string joinArguments(const std::vector<std::string> &args)
 	return res;
 }
 
+std::string escapeArgument(const std::string &arg)
+{
+#ifdef NL_OS_WINDOWS
+	// we can't escape %VARIABLE% on command-line under Windows
+	return arg;
+#else
+	// characters to escapce, only " and $ (to prevent a $something replaced by an environment variable)
+	static const char s_charsToEscape[] = "\"$";
+
+	std::string res;
+	std::string::size_type pos = 0, lastPos = 0;
+
+	// to avoid reallocations
+	res.reserve(arg.size() * 2);
+
+	while ((pos = arg.find_first_of(s_charsToEscape, lastPos)) != std::string::npos)
+	{
+		// add previous part
+		res += arg.substr(lastPos, pos - lastPos);
+		
+		// not already escaped
+		if (!pos || arg[pos - 1] != '\\') res += '\\';
+
+		// add escaped character
+		res += arg[pos];
+
+		lastPos = pos+1;
+	}
+
+	res += arg.substr(lastPos);
+
+	return res;
+#endif
+}
+
 /*
  * Display the bits (with 0 and 1) composing a byte (from right to left)
  */