The indexer was creating a packfile object separately from the
code in pack.c which was a problem since I put a call to
git_mutex_init into just pack.c. This commit updates the pack
function for creating a new pack object (i.e. git_packfile_check())
so that it can be used in both places and then makes indexer.c
use the shared initialization routine.
There are also a few minor formatting and warning message fixes.
This adds some basic tests for the oidmap just to make sure that
collisions, etc. are dealt with correctly.
This also adds some tests for the new caching that check if items
are inserted (or not inserted) properly into the cache, and that
the cache can hold up in a multithreaded environment without error.
