The `block_reader` structure is used to access parsed data of a reftable
block. The structure is currently treated as an internal implementation
detail and not exposed via our public interfaces. The functionality
provided by the structure is useful to external users of the reftable
library though, for example when implementing consistency checks that
need to scan through the blocks manually.
Rename the structure to `reftable_block` now that the name has been made
available in the preceding commit. This name is in line with the naming
schema used for other data structures like `reftable_table` in that it
describes the underlying entity that it provides access to.
The new data structure isn't yet exposed via the public interface, which
is left for a subsequent commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `struct reftable_reader` subsystem encapsulates a table that has
been read from the disk. As such, the current name of that structure is
somewhat hard to understand as it only talks about the fact that we read
something from disk, without really giving an indicator _what_ that is.
Furthermore, this naming schema doesn't really fit well into how the
other structures are named: `reftable_merged_table`, `reftable_stack`,
`reftable_block` and `reftable_record` are all named after what they
encapsulate.
Rename the subsystem to `reftable_table`, which directly gives a hint
that the data structure is about handling the individual tables part of
the stack.
While this change results in a lot of churn, it prepares for us exposing
the APIs to third-party callers now that the reftable library is a
standalone library that can be linked against by other projects.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The license headers used across the reftable library doesn't follow our
typical coding style for multi-line comments. Fix it.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert the reftable library to use the `reftable_buf` interface instead
of the `strbuf` interface. This is mostly a mechanical change via sed(1)
with some manual fixes where functions for `strbuf` and `reftable_buf`
differ. The converted code does not yet handle allocation failures. This
will be handled in subsequent commits.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Handle allocation failures in `new_indexed_table_ref_iter()`. While at
it, rename the function to match our coding style.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `reftable_table` interface provides a generic infrastructure that
can abstract away whether the underlying table is a single table, or a
merged table. This abstraction can make it rather hard to reason about
the code. We didn't ever use it to implement the reftable backend, and
with the preceding patches in this patch series we in fact don't use it
at all anymore. Furthermore, it became somewhat useless with the recent
refactorings that made it possible to seek reftable iterators multiple
times, as these now provide generic access to tables for us. The
interface is thus redundant and only brings unnecessary complexity with
it.
Remove the `struct reftable_table` interface and its associated
functions.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move functions relating to the reftable iterator from "generic.c" into
"iter.c". This prepares for the removal of the former subsystem.
While at it, remove some unneeded braces to conform to our coding style.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The filtering ref iterator can be used to only yield refs which are not
in a specific skip list. This iterator has an option to double-check the
results it returns, which causes us to seek the reference we are about
to yield via a separate table such that we detect whether the reference
that the first iterator has yielded actually exists.
The value of this is somewhat dubious, and I cannot think of any usecase
where this functionality should be required. Furthermore, this option is
never set in our codebase, which means that it is essentially untested.
And last but not least, the `struct reftable_table` that is used to
implement it is about to go away.
So while we could refactor the code to not use a `reftable_table`, it
very much feels like a wasted effort. Let's just drop this code.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Whenever we advance a subiter we first call `iterator_is_null()`. This
is not needed though because we only ever advance subiters which have
entries in the priority queue, and we do not end entries to the priority
queue when the subiter has been exhausted.
Drop the check as well as the now-unused function. This results in a
surprisingly big speedup:
Benchmark 1: show-ref: single matching ref (revision = HEAD~)
Time (mean ± σ): 138.1 ms ± 4.4 ms [User: 135.1 ms, System: 2.8 ms]
Range (min … max): 133.4 ms … 167.3 ms 1000 runs
Benchmark 2: show-ref: single matching ref (revision = HEAD)
Time (mean ± σ): 134.4 ms ± 4.2 ms [User: 131.5 ms, System: 2.8 ms]
Range (min … max): 130.0 ms … 164.0 ms 1000 runs
Summary
show-ref: single matching ref (revision = HEAD) ran
1.03 ± 0.05 times faster than show-ref: single matching ref (revision = HEAD~)
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are a bunch of locations where we initialize members of `struct
block_iter`, which makes it harder than necessary to expand this struct
to have additional members. Unify the logic via a new `BLOCK_ITER_INIT`
macro that initializes all members.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This supports reading a single reftable file.
The commit introduces an abstract iterator type, which captures the usecases
both of reading individual refs, and iterating over a segment of the ref
namespace.
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Patrick Steinhardt