Hook a specific function in a dll

Question

Is it possible to hook all the processes, or find out when a specific function in a dll is called? I want to be able to catch this call and inject my own code / deny access to this function. How can I do this without looping through all the processes and hook each one of them? Is it possible to do so without altering system files? (I'm planning on doing this on an android device and I don't want to require a root)

Answer 1

Simply write a dll with the same ABI.

The idea is to make you dll call the equivalent functions from the original dll, eventually adding a special process, or do nothing or report an unauthorized call if necessary.