Changes:
* Make patty_ax25_sock_ack() take a N(R) argument directly, rather
than having the caller specify N(R)-1
* Only perform acknowledgement of frames within the range between
V(A) and N(R)-1
Implement patty_timer_init() to allow the caller to specify a timer
value to use each time patty_timer_start() is called, obviating the need
to pass the same argument redundantly; if the timer value must be
changed, then another call to patty_timer_init() may be used
Implement frame segmentation/reassembly state machine as per AX.25 v2.2
specifications, as per Section 6.6 "Disassembler/Reassembler" and
associated appendices
Reduced default I frame info field to 127 bytes so as to hopefully
better coincide with common TNC firmware; it is suspected (but not
confirmed that they do include the protocol identifier as part of the
info field length
Use default I frame lengths for common TNCs per version; for AX.25
prior to 2.2, use 128, otherwise, use 255, the maximum for Kenwood and
possibly other Kantronics-style TNCs
When a remote station wishes to connect by sending an XID frame, use
Timer T1 to send an XID response up to the retry count before closing
the socket pending negotiation
Changes:
* Add validation to accept() to ensure file descriptors provided
refer to SOCK_STREAM sockets in the SOCK_LISTENING state
* Rather than writing a reply to the patty client socket when
accepting a SABM or SABME request, write a message to the
remote end of the listening socket; this avoids issues wherein
a client receives an unexpected accept() response that may be
unrelated to another pending request; this also allows client
code to use select(2) on listening sockets
* In patty_client_accept(), send the initial request to validate
that the local socket can accept connections, and then wait for
a connection to be made, reading a message written to the
listening socket from the patty server
* Allow select(2) to notify on accepted connections
Changes:
* Don't clear socket from an interface's promiscuous socket table if
the socket state is not SOCK_PROMISC
* Destroy socket TNC if socket type is SOCK_RAW
* Only attempt to close socket file descriptors >0
Changes:
* Replace usage of gettimeofday() with clock_gettime() in the main
event loop, patty_ax25_server_run(), as gettimeofday() apparently
goes backwards in time occasionally, as per:
https://bugzilla.redhat.com/show_bug.cgi?id=174390
Thanks Iain MM0ROR!
* Fix patty_timer_expired() to properly return true if the
remaining number of seconds is zero, but the remaining higher
precision time is less than zero
* Implement patty_timer_sub() to subtract two struct timespec
values, as glibc lacks timespecsub()
Changes:
* Implement handle_sock_dgram() to specifically handle datagram
(UI frame-only) sockets; this fixes issues wherein logic
specific to SOCK_STREAM timers would be erroneously applied
to datagram sockets
* Always tick Timers T1, T2 and T3
* Some slight code reorganization for improved readability of
control flow
Fix select() portability issues in src/server.c by using gettimeofday()
immediately prior to and after calling select() to calculate elapsed
time since blocking on select()
Implement PATTY_AX25_SOCK_DGRAM type sockets as a means of exchanging UI
frames between stations without requiring calling code to encode and
decode UI frames explicitly
