nested functions search

I want to write a shell script which traverses a cpp file.

Suppose there is function fncn_name6 .. which is called by fncn_name5
which in turn called by fncn_name4 and so on .. in a single cpp class.

ie

fncn_name1
{
fncn_name2
{
fncn_name3
}
{
fncn_name4
}
}

so fncn_name1 is calling function for fncn_name2, fncn_name2 for fncn_name 3 and so on ..

I need to get this flow ... which fncn calls whom....

Please help me wid ur suggestions