Initial work by Bartek Szatkowski in https://github.com/ARMmbed/mbed-os/pull/4079,
reworked following review of https://github.com/ARMmbed/mbed-os/pull/5202 to
transform the entire system into C++, retaining the basic functionality.
Bartek's summary:
* Porting ethernet to EMAC
* Updating EMAC to enable multiple interfaces
* Untangling networking classes, making the abstractions a bit clearer to follow, etc
* General refactoring
* Removal of DEVICE_EMAC flag and introducing DEVICE_ETH and DEVICE_WIFI
Revisions since initial branch:
* Remove lwip depencies
* Correct doxygen warnings
* Remove emac_api.h, replace with C++ EMAC abstract class.
* Create OnboardNetworkInterface, and LWIP implementation.
* Mappings since #4079
lwip-interface/nsapi_stack_lwip.c -> LWIPStack.cpp
lwip-interface/ipstack_lwip.c -> LWIPInterface.cpp
netsocket/mbed_ipstack.h -> OnboardNetworkStack.h
hal/emac_api.h -> EMAC.h
* Reinstate use of EthInterface abstraction
* Correct and clarify HW address EMAC ops
* Restore MBED_MAC_ADDR implementation
* Integrate PPP support with LWIP::Interface.
* Convert K64F lwIP driver to K64F_EMAC.
To do:
* Convert emac_stack_mem.h to follow this pattern.
* Figure out DEVICE_ETH/EMAC
* Update all drivers to use EMAC
To allow a network stack to support both NSAPI and its own options, try to make
sure the NSAPI levels don't collide with level numbers likely to be used by
network stacks.
Distinguish between socket and stack options, and tighten up documentation. Add
IP MRU stack options as an example (implementation not immediately planned for
any stack, but could be useful).
nsapi_error_t - enum of errors or 0 for NSAPI_ERROR_OK
nsapi_size_t - unsigned size of data that could be sent
nsapi_size_or_error_t - either a non-negative size or negative error