TLeconte#116

TLeconte#107

TLeconte#106

TLeconte#111

TLeconte#111

- avoid special-casing IPv6 (AF_UNSPEC already handles it)
- avoid keeping multiple copies of the Rawaddr parameter
- avoid redundant (and useless) error checks
- avoid redundant checks in Netout*()
- avoid running strlen() over buffer when snprintf() is guaranteed to
  return the buffer size
- avoid duplicating the prepared JSON buffer, send it natively instead
  (tested working with airframes.io)
- use static buffers for Netoutpp() and Netoutsv() to reduce stack pressure

Fixes: TLeconte#112

This fixes the following problem:

Found 3 device(s):
  0:  Realtek, RTL2838UHIDIR, SN: 00000003
  1:  Realtek, RTL2838UHIDIR, SN: 00000002
  2:  Realtek, RTL2838UHIDIR, SN: 00000001

`acarsdec -r 00000002` would select the device with serial 00000001
`acarsdec -r 00000001` would select the device with serial 00000002

This patch disambiguates explicit serials by skipping matching device ID
number when the passed argument is exactly 8 characters long, like a
fully qualified serial.

This patch is designed to be as short a diff as possible while preserving
existing behaviour for all but 8-character long arguments.

- move common global variables out of #define scope
- exit with an error if more than one input is selected
- reformat the usage help text
- rename rtlMult -> rateMult (in line with soapy)
- adjust rtl and soapy gain routines to work with floats

cmake -Drtl=ON -Dsoapy=ON -Dairspy=ON works and builds

This reverts commit 22f0c81.

Does this solve an actual problem? dumpvdl2 doesn't have similar code.
This runs an extraneous thread and uses nonportable pthread API.
-Drtl=ON now builds on macOS

Does this solve an actual problem? Neither dumpvdl2 nor common examples
have similar code. This runs an extraneous thread and uses nonportable
pthread API. -Dsoapy=ON now builds on macOS

Additionally:
- add some error checking
- retry on SOAPY_SDR_OVERFLOW (previous code wouldn't work either without it)
- gracefully retry on zero-reads
- don't free in buffer while read() may still be in-flight
- remove unnecessary global variables

PS: this needs so much more work :/

- No functional change.
- Some unused vars have been removed.

- No functional change.
- Some unused vars have been removed.

- Simplify the logic (use the median value of min and max frequency)
- Switch all Fc/minFc/maxFc references to unsigned int

This also "fixes" the following warning:
warning: taking the absolute value of unsigned type 'unsigned int' has no effect [-Wabsolute-value]

First pass at cleaning the mess, using Linux kernel clang-format rules
(without ColumnLimit) and a handful of manual adjustements.

No code change.

don't explicitly zero R initializers (zeroing is implicit)

allows decoding an arbitrary number of channels, limited only by CPU
and memory.

channels.Fr is now unsigned int, adjust casts accordingly until further
cleanup.

Remove malloc() casts.
No code change.

find it through pkg-config since we're already using that for libacars
and make it a hard dependency for now.

We no longer need the various -D<radio>=On since we can build them all
simultaneously. Instead, print an informative message when the
corresponding library is or isn't found.

also make MQTT support depend on it.

This commit enables the use of multiple concurrent outputs, using the
following syntax:

acarsdec --output format:destination:parameters [--output ...]

Where "format" is one of:
- "oneline" for single line text decoding
- "full" for full text decoding
- "monitor" for live decoding
- "pp" for PlanePlotter
- "native" for Acarsdec native format
With CJSON support enabled:
- "json" for JSON output
- "routejson" for flight route output in JSON format

and "destination" is one of:
- "file" for file (including stdout) output
- "udp" for network output over UDP
With MQTT support enabled:
- "mqtt" for MQTT output

Not all combinations of format and destination are valid, acarsdec will
complain if an invalid combination is chosen.

params are described in respective source file (TODO: update usage())

Fixes: TLeconte#76

No functional change

this is completely redundant with the check in blk_thread() and adds
extra processing time in the sample processing path.

This reduces memory pressure and cache trashing and speeds up execution.
outputmsg() no longers allocates memory unnecessarily and operates on
the data passed on from acars blk_thread(), which it only modifies once
(nul-termination at suffix position - necessary as cJSON doesn't have
primitives to limit string length).

This is faster, especially considering that the source will typically be
all-but-last non-nulls.

msg is zeroed on initialization

Use memcpy() instead of for loops and entirely skip parsing if text_len
is too short. Avoids redundant tests.

This speeds up execution by not trying each if() in sequence and makes
the function operation clearer. Using immediate returns instead of a
function pointer and single return point allows aggressive auto-inlining

'bs' is only used once locally in outputmsg()

use explicit size relationships for null-terminated copies

'msn_seq' is only used once locally in outputmsg()

Move one member outside of #ifdef since it's a standard type and this
makes packing deterministic.

use sf_readf_float() and close input file on exit

This partly addresses TLeconte#109
until a proper raw IQ input is added, and replaces
TLeconte#110 as a more generic
implementation

use '--sndfile <file>' as previously for all containers supported by
libsndfile.
use '--sndfile <file>,subtype=<N>' for raw audio processing with <N>
being a supported subtype value as specified in sndfile.h. Optionally,
'channels=<M>,endian=<end>' can be added to decode <M> channels (default
1 if not specified) using <end> endianness, where <end> is one of 'big',
'little' or 'cpu' (default 'cpu' if not specified).

use '-m' to change the multiplier from the default '1'

GCC is apparently not as smart as clang to identify uninitialized uses

Fixes: d6b48ae