rewire/example

Example Wire Kit

The wire kit implemented in main.cpp hooks into all entries to open and openat system calls and logs the filenames given to them. In wirekit_command_exit, it prints the compiled list of all opened files. An important note is the reason to not print in the system call entry hooks themselves: the hosted commands use the same shell as the wire kit, by default. If you run e.g. vim but have a wire kit print in the middle of it, the output messes with vim's own control of the console. To prevent this, either accumulate all output until the command has finished executing or spawn a separate shell from within the wire kit, either when it is prepared or a command is started.