Nobody should ever be using anything other than ALL at this level, so
remove the option altogether.
As part of this, git_reference_foreach_glob is now implemented in the
frontend using an iterator. Backends will later regain the ability of
doing the glob filtering in the backend.
We use p->index_map.data to check whether the struct has been set up
and all the information about the index is stored there. This variable
gets set up halfway through the setup process, however, and a thread
can come along and use fields that haven't been written to yet.
Crucially, pack_entry_find_offset() needs to read the index version
(which is written after index_map) to know the offset and stride
length to pass to sha1_entry_pos(). If these values are wrong,
assertions in it will fail, as it will be reading bogus data.
Make index_version the last field to be written and switch from using
p->index_map.data to p->index_version as "git_pack_file is ready" flag
as we can use it to know if every field has been written.
Older versions of git would only write peeled entries for
items under refs/tags/. Newer versions will write them for
all refs, and we should be prepared to handle that.
There is an occasional assertion failure in sha1_entry_pos from
pack_entry_find_index when running threaded. Holding the mutex
around the code that grabs the index_map data and processes it
makes this assertion failure go away.
When diff encounters an untracked directory, there was a shortcut
that it took which is not compatible with core git. This makes
the default behavior no longer take that shortcut and instead look
inside the untracked directory to see if there are any untracked
files within it. If there are not, then the directory is treated
as an ignore directory instead of an untracked directory. This
has implications for the git_status APIs.
In preparation for more changes to the internal diff logic, it
seemed wise to split the very large git_diff__from_iterators into
separate functions that handle the four main cases (unmatched old
item, unmatched new item, unmatched new directory, and matched
old and new items). Hopefully this will keep the logic easier to
follow even as more cases have to be added to this code.
