Somebody help me to find where is source code(file) to capture following information in samba4

[KS Tan]

Hi all,

Due to I don't have much knowledge in samba source code and I don't want
to mess up the development. So I want to do my own testing inside the
samba 4 source code. So, anybody can tell me which file I should edit to
achive following task:-

1. After user logon, I want to know who is the user and I want to
perform some action inside the source code.
2. After user logout, I want to know who is the user  and I want to
perform some action inside the source code.
3. After user logon, I want to choose a script and ask the user to run
the script.

I don't mind to open up 10-20 pages of source code to achieve my goal,
but the problem is I totally don't know where to start.

Any help is appreciated
Ks