[O] Open an org-mode file from C++ source code and automatically create an item

[Lex Fridman]

I'm working on a C++ project. Suppose I have the following directory structure:

project/
project/src

And I have the following files:

project/ChangeLog
project/todo.org
project/src/foo.cpp

I can work on the C++ source code in `foo.cpp` and then add a line
into the ChangeLog file just with `C-x 4 a` as the following
describes: http://bit.ly/kpcDSp

How can I achieve that same kind of functionality with org-mode on the
file `todo.org`. I would like to keep a to do list relative to the
source code. So if in `foo.cpp` I need to finish a function `void
Foo::bla()` I would like an entry to be added to `todo.org` that
mentions this function and the file it resides in much like `C-x 4 a`
does for ChangeLog.

I would also like to be able to have the backward link from the org
file to the `foo.cpp` file in which the to-do task is.

There is so much documentation, tutorials, information available on
org-mode, so I'm sorry if I'm asking a dumb question that's already
been covered extensively elsewhere. I tried searching Google and this
mailing list, but found nothing that addresses this.

Thanks!