Problem Statement:
During multicast join sequence, InternetSocket::join_multicast_group() calls InternetSocket::modify_multicast_group(). modify_multicast_group() sets up the multicast group address (i.e., mreq.imr_multiaddr) to be joined and the interface address (i.e., mreq.imr_interface) to be used for the multicast join request. The interface address is initialized with the default value, which sets the version of interface address to NSAPI_UNSPEC. This results in LWIP::setsockopt() API to attempt IPv6 multicast join on the IPv4 interface address, hence IPv6 multicast join always fails with the protocol error.
Fix:
Initialize interface address version based on the multicast address version in LWIP::setsockopt(), before attempting multicast join operation.
Created (a new) PPP interface for PPP service. Removed lwip
dependencies to PPP (memory allocations etc.). Moved PPP
configuration options away from lwIP mbed_lib.json to new
PPP service. For backwards compatibility, using the old
options is also currently supported.
If "lwip.tcp-enabled" is set to false, ARMC6 compilation fails to error
Error: L6218E: Undefined symbol netconn_recv_tcp_pbuf
LWIP::socket_recv() is TCP socket specific method so implementation can be
enabled only when LWIP_TCP flag is set.
Slight RAM+speed efficiency improvement - read the TCP implementation's
native pbufs, rather than forcing netconn_recv to generate netbuf
wrappers for us. Saves one small lwIP heap allocation per TCP packet
received.
Deprecate wait() in favour of acquire(), try_acquire(),
try_acquire_for() and try_acquire_until().
Brings Semaphore more into line with CMSIS-RTOS 2 (which uses "acquire"),
itself (as it has "release"), and other classes having "try", "try for"
and "try until".
Also steps away from vague "wait" term - the primary operation here is
to acquire the semaphore, and this will of course sleep.
If TCP FSM is in ESTABLISHED state, waits for TCP close handshaking until TIME_WAIT
The purpose is to prevent eth/wifi driver stop and FIN ACK corrupt.
This may happend if network interface disconnect follows immediately after socket_close.
Added Multihoming feature to LWIP (ability to use more than one network interfaces) for increasing networking reliability.
This involves:
LWIP interface
LWIP IP routing
DNS storage
Sockets (bind to interface name possibility)
possibility to add non default network interface
cellular middleware modifications if cellular connection is used