Lift restriction on json-c <= 0.12.1
ipc-server: Acquire ownership of referenced json_object properly
When adding a referenced json_object with an unknown lifetime to
another json_object, it must be done with a wrapped call to
json_object_get() to acquire the ownership of that json_object.
The default max nesting depth of json-c is 32, which can cause some valid trees to fail to be parsed, so increase that. Also instead of segfaulting, just abort and print the error returned by json-c.
Increase _POSIX_SOURCE value where needed.
Increase _XOPEN_SOURCE value where needed.
Conditionally link to libcap (only on Linux).
Possibly some trailing whitespace fixes (automatic).
