In order to give advanced control over a processing queue,
it would be better to have the checking function separated from
the osmo_gapk_pq_prepare(). Moreover, this change introduces an
additional 'strict' checking mode that requires a queue to have
a source item first and a sink item in the last position.
This change adds two meta-information fields to the processing
queue item structure. Both of them will be used for more
detailed logging and for the human-readable processing
queue description.
Since this change, every processing queue may optionally have
an associated human-readable name. If name is not required,
NULL should be passed to the osmo_gapk_pq_create().
In order to simplify memory leak debugging, this change introduces
the library's internal talloc context that may be changed by
external application by calling the osmo_gapk_set_talloc_ctx().
Since this change, the libosmogapk uses the Osmocom logging
framework. By default, logging is disabled and could be enabled
by the external applications calling the osmo_gapk_log_init()
with a desired log target as an argument.
The usage of linuxlist is more flexible than having a limited
array of pointers. This approach allows to have as much items
in a processing queue as required.
To avoid a naming conflict between libosmogapk and other projects
during linkage, all the exposed symbols should have an unique
prefix. Let's use 'osmo_gapk' for that.
To be able to use the library, external applications need to know,
which symbols are exposed. This information is provided by header
files, which are being installed to a system's ${includedir}
since this change.