sgsn: Add SGSN_ERROR_CAUSE_NONE and use it instead of 0

Currently an error_cause of 0 is being used to indicate normal
operation. Albeit this is not a defined GMM cause, the value is not
explicitly reserved.

This commit adds the macro SGSN_ERROR_CAUSE_NONE and uses it for
initialisation (instead of relying on talloc_zero) and comparisons.
The value is set to -1 to be on the safe side. The VTY code is
updated to set the error_cause when using the
'update-subscriber imsi IMSI update-location-result CAUSE' command.

Sponsored-by: On-Waves ehf
5 files changed
tree: 99156a4e36f626b965c72d59476bae95dfc70a63
  1. debian/
  2. hlrsync/
  3. linux-kernel/
  4. openbsc/
  5. wireshark/
  6. README