Now that all callbacks of the loose source operate on `struct
odb_source_loose` directly we no longer have to reach into the "files"
source at all.
Drop this field and update `odb_source_loose_new()` to instead accept
all parameters required to initialize itself. This ensures that the
"loose" backend is a fully standalone source.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Wire up the `write_object_stream()` callback.
Note that we don't move the implementation into "odb/source-loose.c".
This is because most of the logic to write loose objects is still
contained in "object-file.c", and detangling that requires us to do some
refactorings as explained in the preceding commit. So for now, the
implementation of writing an object stream is still located in
"object-file.c".
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "object-file" subsystem still hosts the majority of logic used to
write loose objects. Eventually, we'll want to move this logic into
"odb/source-loose.c", but this isn't yet easily possible because a lot
of the writing logic is still being shared with `force_object_loose()`.
We will eventually detangle this logic so that we can indeed move all of
it into the "loose" source. Meanwhile though, refactor the code so that
it operates on a `struct odb_source_loose` directly to already make the
dependency explicit.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move `odb_source_loose_write_object()` from "object-file.c" into
"odb/source-loose.c" and wire it up as the `write_object()` callback of
the loose source.
As in preceding commits, this requires us to expose a couple of generic
functions from "object-file.c" as they are used in both subsystems now.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move `odb_source_loose_freshen_object()` from "object-file.c" into
"odb/source-loose.c" and wire it up as the `freshen_object()` callback
of the loose source.
As part of the move, `check_and_freshen_source()` is inlined into the
callback function, as it has no other callers anymore.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move `odb_source_loose_count_objects()` and its associated helpers from
"object-file.c" into "odb/source-loose.c" and wire it up as the
`count_objects()` callback of the loose source.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move `odb_source_loose_find_abbrev_len()` and its associated helpers
from "object-file.c" into "odb/source-loose.c" and wire it up as the
`find_abbrev_len` callback of the loose source.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move `odb_source_loose_for_each_object()` and its associated helpers
from "object-file.c" into "odb/source-loose.c" and wire it up as the
`for_each_object()` callback of the loose source.
Again, as in the preceding commit, we are forced to expose a couple of
functions from "object-file.c" that are now used by both subsystems.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move `odb_source_loose_read_object_stream()` and its associated helpers
from "object-file.c" into "odb/source-loose.c" and wire it up as the
`read_object_stream()` callback of the loose source.
As part of the move we are also forced to expose a couple of functions
from "object-file.h" that parse object headers in a somewhat-generic
way, as those functions are now used by both subsystems.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move `odb_source_loose_read_object_info()` from "object-file.c" into
"odb/source-loose.c" and wire it up as the `read_object_info()` callback
of the loose source. Callers that previously invoked it directly now go
through the generic `odb_source_read_object_info()` interface instead.
The function `read_object_info_from_path()` cannot be moved along with
it because it is still called by `for_each_object_wrapper_cb()`. It is
therefore kept in place, but adjusted to take a loose source to clarify
that it's always operating on this structure.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Wire up a new `close()` callback for the loose source and call it from
the "files" source via the generic `odb_source_close()` interface. The
callback itself is a no-op as the loose source has no resources that
need to be released on close.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move `odb_source_loose_reprepare()` from "object-file.c" into
"odb/source-loose.c" and wire it up as the `reprepare()` callback of the
loose source.
While at it, make `odb_source_loose_clear_cache()` static, as it is no
longer needed outside of its file.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Start converting `struct odb_source_loose` into a proper pluggable
`struct odb_source` by embedding the base struct and assigning it the
new `ODB_SOURCE_LOOSE` type. Furthermore, wire up lifecycle management
of this source by implementing the `free` callback and taking ownership
of the chdir notifications.
Note that the loose source is not yet functional as a standalone `struct
odb_source`, as it's missing all of the callback implementations. These
will be wired up in subsequent commits.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `struct odb_source_loose` holds a pointer to its owning parent
source. The way that Git is currently structured, this parent is always
the "files" source. In subsequent commits we're going to detangle that
so that the "loose" source doesn't have any owning parent source at all
so that it can be used as a completely standalone source.
Detangling this mess is somewhat intricate though, and is made even more
intricate because it's not always clear which kind of source one is
holding at a specific point in time -- either the parent "files" source,
or the child "loose" source.
Make this relationship more explicit by storing a pointer to the "files"
source instead of storing a pointer to a generic `struct odb_source`.
This will help make subsequent steps a bit clearer.
Note that this is a temporary step, only. At the end of this series
we will have dropped the parent pointer completely.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We've got a couple of functions that accept `odb_write_object()` flags,
but all of them accept the flags as an `unsigned` integer. In fact, we
don't even have an `enum` for the flags field.
Introduce this `enum` and adapt functions accordingly according to our
coding style.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new generic `odb_find_abbrev_len()` function as well as
source-specific callback functions. This makes the logic to compute the
required prefix length to make a given object unique fully pluggable.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `odb_for_each_object()` function only accepts a bitset of flags. In
a subsequent commit we'll want to change object iteration to also
support iterating over only those objects that have a specific prefix.
While we could of course add the prefix to the function signature, or
alternatively introduce a new function, both of these options don't
really seem to be that sensible.
Instead, introduce a new `struct odb_for_each_object_options` that can
be passed to a new `odb_for_each_object_ext()` function. Splice through
the options structure into the respective object database sources.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce generic object counting on the object database source level
with a new backend-specific callback function.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new callback function in `struct odb_source` to make the
function pluggable.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new callback function in `struct odb_source` to make the
function pluggable.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new callback function in `struct odb_source` to make the
function pluggable.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new callback function in `struct odb_source` to make the
function pluggable.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new callback function in `struct odb_source` to make the
function pluggable.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new callback function in `struct odb_source` to make the
function pluggable.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new callback function in `struct odb_source` to make the
function pluggable.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new callback function in `struct odb_source` to make the
function pluggable.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new callback function in `struct odb_source` to make the
function pluggable.
Note that this function is a bit less straight-forward to convert
compared to the other functions. The reason here is that the logic to
read an object is:
1. We try to read the object. If it exists we return it.
2. If the object does not exist we reprepare the object database
source.
3. We then try reading the object info a second time in case the
reprepare caused it to appear.
The second read is only supposed to happen for the packfile store
though, as reading loose objects is not impacted by repreparing the
object database.
Ideally, we'd just move this whole logic into the ODB source. But that's
not easily possible because we try to avoid the reprepare unless really
required, which is after we have found out that no other ODB source
contains the object, either. So the logic spans across multiple ODB
sources, and consequently we cannot move it into an individual source.
Instead, introduce a new flag `OBJECT_INFO_SECOND_READ` that tells the
backend that we already tried to look up the object once, and that this
time around the ODB source should try to find any new objects that may
have surfaced due to an on-disk change.
With this flag, the "files" backend can trivially skip trying to re-read
the object as a loose object. Furthermore, as we know that we only try
the second read via the packfile store, we can skip repreparing loose
objects and only reprepare the packfile store.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new callback function in `struct odb_source` to make the
function pluggable.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new callback function in `struct odb_source` to make the
function pluggable.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new callback function in `struct odb_source` to make the
function pluggable.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a caller holds a `struct odb_source`, they have no way of telling
what type the source is. This doesn't really cause any problems in the
current status quo as we only have a single type anyway, "files". But
going forward we expect to add more types, and if so it will become
necessary to tell the sources apart.
Introduce a new enum to cover this use case and assert that the given
source actually matches the target source when performing the downcast.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The primary object database source may be initialized with a relative
path. When the process changes its current working directory we thus
have to update this path and have it point to the same path, but
relative to the new working directory.
This logic is handled in the object database layer. It consists of three
steps:
1. We undo any potential temporary object directory, which are used
for transactions. This is done so that we don't end up modifying
the temporary object database source that got applied for the
transaction.
2. We then iterate through the non-transactional sources and reparent
their respective paths.
3. We reapply the temporary object directory, but update its path.
All of this logic is heavily tied to how the object database source
handles paths in the first place. It's an internal implementation
detail, and as sources may not even use an on-disk path at all it is not
a mechanism that applies to all potential sources.
Refactor the code so that the logic to reparent the sources is hosted by
the "files" source and the temporary object directory subsystems,
respectively. This logic is easier to reason about, but it also ensures
that this logic is handled at the correct level.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "files" backend is implemented as a pointer in the `struct
odb_source`. This contradicts our typical pattern for pluggable backends
like we use it for example in the ref store or for object database
streams, where we typically embed the generic base structure in the
specialized implementation. This pattern has a couple of small benefits:
- We avoid an extra allocation.
- We hide implementation details in the generic structure.
- We can easily downcast from a generic backend to the specialized
structure and vice versa because the offsets are known at compile
time.
- It becomes trivial to identify locations where we depend on backend
specific logic because the cast needs to be explicit.
Refactor our "files" object database source to do the same and embed the
`struct odb_source` in the `struct odb_source_files`.
There are still a bunch of sites in our code base where we do have to
access internals of the "files" backend. The intent is that those will
go away over time, but this will certainly take a while. Meanwhile,
provide a `odb_source_files_downcast()` function that can convert a
generic source into a "files" source.
As we only have a single source the downcast succeeds unconditionally
for now. Eventually though the intent is to make the cast `BUG()` in
case the caller requests to downcast a non-"files" backend to a "files"
backend.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new "files" object database source. This source encapsulates
access to both loose object files and the packfile store, similar to how
the "files" backend for refs encapsulates access to loose refs and the
packed-refs file.
Note that for now the "files" source is still a direct member of a
`struct odb_source`. This architecture will be reversed in the next
commit so that the files source contains a `struct odb_source`.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
