Update all the SDR implementation to use it.
This was getting pretty ugly with code getting copy&pasted in all the SDR
implementations. Unify it all and give it a simpler API. Linked list works out
much simpler than the circular buffer. Also, simplify copying the overlap region
around by just using a separate buffer (it's only a few hundred bytes long, so
the double copy is not a big deal).
The commit provides a basic implementation of support for LimeSDR USB
receivers based on LMS7002 chip. The solution has several limitations:
- passing parameters for tune LimeSDR receiver via command-line
options is not implemented;
- only hardcoded configuration is used (channel 0 of lower band LNA,
LMS_FMT_I16 format, gain, bandwidth and timeout);
- only one device is supported and it is not possible to select a
desired one in case if several devices are connected to the host.
Test: compare the output of the program for RTL and LimeSDR receivers.
Environment:
- RTL2832SDR dongle;
- LMS7002M based USB LimeSDR board;
- 800MHz-2200MHz omnidirectional antenna with SMA connector.
Procedure:
- connect RTL dongle to the host and start the program with the
following parameters:
$ ./dump1090 --device-type rtlsdr --interactive
- wait until several planes will be detected;
- stop the program, connect the LimeSDR board to the host and restart
the program with the following parameters:
$ ./dump1090 --device-type limesdr --interactive
- ensure that the same planes are detected.
Acceptance criteria: the same planes are detected using both receivers
and track information matches with information from the
FlightRadar24 application.
Signed-off-by: Gluttton <gluttton@ukr.net>
Reattach the licenses for the compat stuff to the source.
Only build/link the compat stuff when it's needed.
Rename compat/util.h so it's not confused with util.h.
Move all the platform specific defines inside compat/compat.h.
Move ModeA/C demodulator to demod_2000 (decoding stays in mode_ac.c)
Remove dependency on interactive.c in stats.c
faup1090 then doesn't need interactive.c at all.
This is a from-scratch reimplementation that should be functionally
equivalent to the Flightaware version that was based on dump1090_mr
and had its fingers deep in the network code. This version should be
a little less invasive / fragile..