def _bibfiles(cls, directory, config, endwith):
"""Read the INI-file, yield bibfile instances for sections."""
cfg = INI(interpolation=None)
cfg.read(os.path.join(directory, '..', config))
for s in cfg.sections():
if not s.endswith(endwith):
continue
filepath = os.path.join(directory, s)
assert os.path.exists(filepath)
sortkey = cfg.get(s, 'sortkey')
if sortkey.lower() == 'none':
sortkey = None
yield BibFile(
filepath=filepath,
encoding=cfg.get(s, 'encoding'), sortkey=sortkey,
use_pybtex=cfg.getboolean(s, 'use_pybtex'),
priority=cfg.getint(s, 'priority'),
name=cfg.get(s, 'name'), title=cfg.get(s, 'title'),
description=cfg.get(s, 'description'),
abbr=cfg.get(s, 'abbr'))
