fix: better exit behavior with plugin sources

[ldegio]

When using a source plugin, force an exit only if the plugin is actually stuck on a next(), not if it's working on the close()

Signed-off-by: Loris Degioanni loris@sysdig.com

[FedeDP]

If i undestand the code correctly:

• if signal_callback is called while a plugin is inside next, we set g_terminate to true, and wait 3 more seconds

• then, if the plugin is still frozen inside next, we will exit the program (because g_terminating will still be false)

• If, instead, during those 3 seconds, we are now in g_terminating mode (ie: we are closing the live capture), what is supposed to happen here?
  We will have both g_terminate and g_terminating true, and we will loop on alarm(3); forever, right?

Perhaps i am missing some pieces here :)

[ldegio]

correct. The idea is:

• if g_terminating doesn't get set, it means a plugin (or, more generally, the reader) is stuck on open() or next(). We assume such behavior is not good and in that case we exit
• if g_terminating is set, it means that the plugin is working on close(). We assume it's well behaved and it will eventually return (cleanup can take time) and we just let it go forever

[FedeDP]

I see now, thanks!

[FedeDP]

/approve