Replace single quote with two quotes in XSLT

I know most of the people will not need it as very rare this requirement comes and because of it we have to waste hours and hours. In net there are plenty of articles, posts says about how to do replace in XSLT. But, most of them has some requirements like the replace() built in method needs XSLT 2.0 version, or some thing something.... But, if you need simple replace method regardless of the version you have, then you are at right place. There are lot of custom functions written on this already. But, no one of them works for the requirement I have. That is replacing the single quote with two quotes in XSLT. 

The main requirement here is, I am more of SharePoint guy, I use infopath forms for collecting data from users and save them to backend[database]. In the process of it, I have comments fields in the form. There are chances that user may enter single quotes['] in their comments. But, while saving them to the database, the single quote ['] giving problems. Everyone knows that this is the basic problem. So, I have to replace single quote with two single quotes so that the problem will go away.