finding the string before a special character

Suppose i have an xml file.
i have to write an xsl file so that it should allow characters from
a-z and A-Z and numbers and '_' and '/'.
if the string is having any other character then it should display the string before the special character.
if the string is not having any other special characters then it should display normally.

my xml file is:

<?xml version="1.0"?>
<emp>
<name>srini$sdg</name>
<name>rama</name>
<name>rameshs@dg</name>
<name>r)amki</name>
<name>ragi</name>
</emp>

in this case the output should be :
srini
rama
rameshs
r
ragi
pease give a solution to this.
thanks
srini.