The serial parser will now allow specifying a custom user-provided filter, which
is applied before even trying to match successful/error responses. This filter
provides a very early barrier to detect strings that are clearly not going to
match.
E.g. this filter may be used during port probing to early detect non-AT ports.
Given that we now perform our own built-in echo removal in the v1 parser, we no
longer need the v1_e1 parser.
The v0 parser was also unused from long ago.
Instead of vague "send something, wait something" the responses are now
analyzed by (overridable) parsers. Makes all the modem implementations much
easier since each caller knows without any code whether the call succeeded
or failed.
Another thing that makes modem code simpler (and the whole thing more robust),
is the queueing of sent commands. Each queued command has a command and a
callback which is quaranteed to get called, even if sending failed.
Define and implement error reporting.
Aleksander Morgado
Alexander Sack
Tambet Ingo