If a process exits and has a controlling terminal, everything under
it gets a SIGHUP by the kernel. That's the case for instance when
running a srsUE over ssh with some specific parameters. As a result,
when the ssh client is killed, SIGHUP is sent to srsUE, which will be
killed immediatelly without proper release, which means in turn that log
buffers are not flushed.
Let's do proper shutdown when SIGHUP is received so that everyone can
get log files.
SIGKILL cannot be intercepted by apps, so it's useless adding a signal
handler for them. I'm pretty sure the signal() function is erroring in
this scenarios. From signal() man page:
"The signals SIGKILL and SIGSTOP cannot be caught or ignored."
* first step towards moving MAC timers to stack. Mac is still using its own timers. srslte::timers class can be restructured.
* moved timers out of the UE MAC
this will also extend all classes that use srslte::thread
to specify the name of the thread in the ctor as well
as to set the name of the worker threads in the thread pool
the thread name will be displayed in gdb.
This entails:
* Adding S1AP paging messaging to the MME.
* Adding the Downlink Data Notification, Donlink Data Notification Acknoledgment, and Downlink Data Notification Failure Messages.
* Adding the logic at the GTP-U to detect that Downlink Data notification needs to be sent.
* Proper handling of the new GTP-C messages at the MME GTPC and SPGW GTPC classes
* Add queuing mechanisms at the GTP-U while waiting for paging response. Queue is flushed when paging fails (timeout or other).
* Make sure eNB's SCTP information is properly stored.
* Make sure UE's GUTI information is properly stored.
* Adding timer creation at NAS using timerfd_create
* Adding the ability to add and remove the timer file descriptor to the MME main select loop
* Adding the ability to the MME for the NAS to check if a timer is running
* Adding the timer expiry handling functionality at the MME