To allow switching between transmit and receive mode within a single
flow graph, I've followed the model used by the BladeRF: I factored
common code into hackrf_common.cc and hackrf_common.h, and created a
"_devs" map there to keep track of which devices have been previously
opened. Shared pointers are used to track how many source & sink blocks
are using a particular device.
Because some properties (center frequency, sample rate, bandwidth, RF
amplifier state, bias tee) are shared between receive and transmit, the
blocks defer setting these until receiving or transmitting is started.
That way a source and sink can safely use different values for these
properties, and the correct values are set during T/R switching.
Because the HackRF driver and/or hardware does not seem to fully
transmit all samples sent to it, the code adds some silence to the end
of transmissions to ensure all samples are transmitted.
I've also replaced boost with C++11 code where possible.
From: Clayton Smith <argilo@gmail.com>
Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
