tweak_key_file

Emitted from load_file just prior to instantiating an ServerSideSource.

Signal handlers can tweak the key_file content as necessary and return true to write the modified content back to disk.

For the purposes of tweaking, it's easier to deal with a plain KeyFile than an Source instance. An Source, for example, does not allow key file groups to be removed.

The return value is cumulative. If any signal handler returns true, the key_file content is written back to disk.

Parameters:

key_file	a KeyFile
uid	a unique identifier string for key_file

Returns:

true if key_file was modified, false otherwise