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.
This modem is a special case. It uses a given socket ID value rather
than providing one. A naive solution here would be to directly map the
index of a CellularSocket object in the CellularSocket container. But
considering the case where there are multiple sockets being opened (some
sockets being already created at the modem and some yet not created), direct mapping
to indices will not work. As it can happen that the CellularSocket
object is allocated but the socket id is not assigned yet as it is not
actually created on the modem.
In such a case, we check the container and assign the socket id from the
pool if an empty slot was found.
Local modem ip stacks vary in their implementations and the way of
working. Some of the modems may not open a socket until an IP context is
assigned. That's why we came up with a container that stores addresses of
any CellularSocket instances created on-demand by the application. When
the application requests opening a socket we store allocate and store the
premitive in the container however actual socket creation at the modem
may happen at a later stage, e.g., a call to send_to() may result in
actual opening of a socket.
That's why we must not assign socket ids in the CellularSocket object
during construction. It must happen when actual socket is opened and is
alive.
Another implication of the previous model is that we may have multiple
sockets created in our container but the actual socket ids are not
assigned yet, so we cannot directly map the socket id to the container
indices which has been happening previously.
To solve this issue we have promoted the AT_CellularStac::find_socket_index(...) method
to be a protected method rather than being private so that the children
can use the method to determine if the given index in the container
corrsponds to the assigned socket id or not.
We have given up on the socket->created flag and the whole decision
making to actually open a socket on the modem happens on the basis of a
valid socket being assigned or not.
Anna Bridge
Chris Trowbridge
Kimmo Vaisanen
Antti Kauppila
mudassar-ublox
Teppo Järvelin
Martin Kojtal
Mirela Chirica
Ari Parkkila
Kevin Bracey
Bilal Qamar
Hasnain Virk
Daniel Lee