fhpd user interaction (and corefiles)

[Phil Muldoon <pmuldoon@redhat.com>]

In fhpd, there are several scenarios where guessing a user's intentions 
with the data available becomes difficult. Right now the core file code 
makes the decision for you. This is wrong and I would like to change 
that. Consider the scenarios below.

No executable specified:

- The user specifies a corefile, but no executable. The code finds a 
named executable as described in the corefile in 'pwd', does it use it? 
Yes in the current code.
- The user specifies a corefile, but no executable. The code does not 
find a named executable as described in the corefile in 'pwd', but does 
in /usr/bin or /bin, does it use it? Yes in the current code.
- The user specifies a corefile, but no executable. The code does not 
find a named executable in either of the top two scenarios, and just 
builds basic metadata. Yes in the current code.

Executable specified:

- The user specifies a corefile, and an executable, but the executable 
name does not match the name that the corefile has on record, does it 
use this executable, warn the user, or abort? No, it blindly uses the 
executable.
- The user specifies a corefile, and an executable. Both match and the 
corefile code builds rich metadata. Yes in the current code.
- The user specifies a corefile, and an executable. Both match, but 
there are permission issues. How should the core continue here? Right 
now it ignores the executable and builds basic metadata.

One of the sticking points is the dead/LinuxHost.java code does not let 
the hpd/CoreCommand.java know what it is doing. In fact, unless it 
throws an exception in building the corefile metadata ,it does not 
communicate anything at all.  It is even further compounded by fstack 
where beyond current initial bootstrapping there is no bandwidth to ask 
the user anything.

 The question here then: if the LinuxHost code has a question for the 
user, how does it ask that user the question via CoreCommand? As far as 
I can tell, none of the fhpd commands are interactive.

Possible solutions:

- Do exactly as the user instructs. Abandon all attempts at executable 
auto-location. If the user does not specify an executable, no executable 
is loaded or searched for. Only basic meta data is built.
- Allow the user to specify data to the corefile via another command 
later. Like a file command which specifies an executable and allows the 
corefile code to reboot and rebuild itself at a later time.
- Continue with existing plan above, but allows callbacks and active 
user interaction with the fhpd
- Something else?

Regards

Phil