Add codecs for EF_SPN and GSM strings via construct
This will replace the hand-crafted codec for EF_SPN
by a struct definition using the construct library.
Old encoders are updated and kept for API compatibility
but are not used internally anymore.
New data structures:
* Rpad(Adapter): Right-padded bytestring (0xff, adjustable)
* GsmStringAdapter(Adapter): Codec for "SMS default 7-bit
coded alphabet as defined int TS 23.038" using
the gsm0338 library.
* GsmString(n): Convenient wrapper of both above
Adjustments:
* utils: update+deprecate old dec_spn(), enc_spn()
* remove refs to deprecated functions
Change-Id: Ia1d3a3835933bac0002b7c52511481dd8094b994
diff --git a/requirements.txt b/requirements.txt
index 6e8336c..10e9667 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -5,3 +5,4 @@
jsonpath-ng
construct
bidict
+gsm0338