At GitLab, we have a system that creates ephemeral internal refs that
don't live long before getting deleted. Having an option to exclude
certain refs from a packed-refs file allows these internal references to
be deleted much more efficiently.
Add an --exclude option to the pack-refs builtin, and use the ref
exclusions API to exclude certain refs from being packed into the final
packed-refs file
Signed-off-by: John Cai <johncai86@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Dozens of files made use of advice functions, without explicitly
including advice.h. This made it more difficult to find which files
could remove a dependence on cache.h. Make C files explicitly include
advice.h if they are using it.
Signed-off-by: Elijah Newren <newren@gmail.com>
Acked-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* ab/remove-implicit-use-of-the-repository:
libs: use "struct repository *" argument, not "the_repository"
post-cocci: adjust comments for recent repo_* migration
cocci: apply the "revision.h" part of "the_repository.pending"
cocci: apply the "rerere.h" part of "the_repository.pending"
cocci: apply the "refs.h" part of "the_repository.pending"
cocci: apply the "promisor-remote.h" part of "the_repository.pending"
cocci: apply the "packfile.h" part of "the_repository.pending"
cocci: apply the "pretty.h" part of "the_repository.pending"
cocci: apply the "object-store.h" part of "the_repository.pending"
cocci: apply the "diff.h" part of "the_repository.pending"
cocci: apply the "commit.h" part of "the_repository.pending"
cocci: apply the "commit-reach.h" part of "the_repository.pending"
cocci: apply the "cache.h" part of "the_repository.pending"
cocci: add missing "the_repository" macros to "pending"
cocci: sort "the_repository" rules by header
cocci: fix incorrect & verbose "the_repository" rules
cocci: remove dead rule from "the_repository.pending.cocci"
In preceding commits we changed many calls to macros that were
providing a "the_repository" argument to invoke corresponding repo_*()
function instead. Let's follow-up and adjust references to those in
comments, which coccinelle didn't (and inherently can't) catch.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Dozens of files made use of gettext functions, without explicitly
including gettext.h. This made it more difficult to find which files
could remove a dependence on cache.h. Make C files explicitly include
gettext.h if they are using it.
However, while compat/fsmonitor/fsm-ipc-darwin.c should also gain an
include of gettext.h, it was left out to avoid conflicting with an
in-flight topic.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Ever since a64215b6cd ("object.h: stop depending on cache.h; make
cache.h depend on object.h", 2023-02-24), we have a few headers that
could have replaced their include of cache.h with an include of
object.h. Make that change now.
Some C files had to start including cache.h after this change (or some
smaller header it had brought in), because the C files were depending
on things from cache.h but were only formerly implicitly getting
cache.h through one of these headers being modified in this patch.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Code clean-up to clarify the rule that "git-compat-util.h" must be
the first to be included.
* en/header-cleanup:
diff.h: remove unnecessary include of object.h
Remove unnecessary includes of builtin.h
treewide: replace cache.h with more direct headers, where possible
replace-object.h: move read_replace_refs declaration from cache.h to here
object-store.h: move struct object_info from cache.h
dir.h: refactor to no longer need to include cache.h
object.h: stop depending on cache.h; make cache.h depend on object.h
ident.h: move ident-related declarations out of cache.h
pretty.h: move has_non_ascii() declaration from commit.h
cache.h: remove dependence on hex.h; make other files include it explicitly
hex.h: move some hex-related declarations from cache.h
hash.h: move some oid-related declarations from cache.h
alloc.h: move ALLOC_GROW() functions from cache.h
treewide: remove unnecessary cache.h includes in source files
treewide: remove unnecessary cache.h includes
treewide: remove unnecessary git-compat-util.h includes in headers
treewide: ensure one of the appropriate headers is sourced first
sscanf(3) used in "git symbolic-ref --short" implementation found
to be not working reliably on macOS in UTF-8 locales. Rewrite the
code to avoid sscanf() altogether to work it around.
* jk/shorten-unambiguous-ref-wo-sscanf:
shorten_unambiguous_ref(): avoid sscanf()
shorten_unambiguous_ref(): use NUM_REV_PARSE_RULES constant
shorten_unambiguous_ref(): avoid integer truncation
This allows us to replace includes of cache.h with includes of the much
smaller alloc.h in many places. It does mean that we also need to add
includes of alloc.h in a number of C files.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To shorten a fully qualified ref (e.g., taking "refs/heads/foo" to just
"foo"), we munge the usual lookup rules ("refs/heads/%.*s", etc) to drop
the ".*" modifier (so "refs/heads/%s"), and then use sscanf() to match
that against the refname, pulling the "%s" content into a separate
buffer.
This has a few downsides:
- sscanf("%s") reportedly misbehaves on macOS with some input and
locale combinations, returning a partial or garbled string. See
this thread:
https://lore.kernel.org/git/CAGF3oAcCi+fG12j-1U0hcrWwkF5K_9WhOi6ZPHBzUUzfkrZDxA@mail.gmail.com/
- scanf's matching of "%s" is greedy. So the "refs/remotes/%s/HEAD"
rule would never pull "origin" out of "refs/remotes/origin/HEAD".
Instead it always produced "origin/HEAD", which is redundant with
the "refs/remotes/%s" rule.
- scanf in general is an error-prone interface. For example, scanning
for "%s" will copy bytes into a destination string, which must have
been correctly sized ahead of time to avoid a buffer overflow. In
this case, the code is OK (the buffer is pessimistically sized to
match the original string, which should give us a maximum). But in
general, we do not want to encourage people to use scanf at all.
So instead, let's note that our lookup rules are not arbitrary format
strings, but all contain exactly one "%.*s" placeholder. We already rely
on this, both for lookup (we feed the lookup format along with exactly
one int/ptr combo to snprintf, etc) and for shortening (we munge "%.*s"
to "%s", and then insist that sscanf() finds exactly one result).
We can parse this manually by just matching the bytes that occur before
and after the "%.*s" placeholder. While we have a few extra lines of
parsing code, the result is arguably simpler, as can skip the
preprocessing step and its tricky memory management entirely.
The in-code comments should explain the parsing strategy, but there's
one subtle change here. The original code allocated a single buffer, and
then overwrote it in each loop iteration, since that's the only option
sscanf() gives us. But our parser can actually return a ptr/len combo
for the matched string, which is all we need (since we just feed it back
to the lookup rules with "%.*s"), and then copy it only when returning
to the caller.
There are a few new tests here, all using symbolic-ref (the code can be
triggered in many ways, but symrefs are convenient in that we don't need
to create a real ref, which avoids any complications from the filesystem
munging the name):
- the first covers the real-world case which misbehaved on macOS.
Setting LC_ALL is required to trigger the problem there (since
otherwise our tests use LC_ALL=C), and hopefully is at worst simply
ignored on other systems (and doesn't cause libc to complain, etc,
on systems without that locale).
- the second covers the "origin/HEAD" case as discussed above, which
is now fixed
- the remainder are for "weird" cases that work both before and after
this patch, but would be easy to get wrong with off-by-one problems
in the parsing (and came out of discussions and earlier iterations
of the patch that did get them wrong).
- absent here are tests of boring, expected-to-work cases like
"refs/heads/foo", etc. Those are covered all over the test suite
both explicitly (for-each-ref's refname:short) and implicitly (in
the output of git-status, etc).
Reported-by: 孟子易 <mengziyi540841@gmail.com>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The ref_rev_parse_rules[] array is terminated with a NULL entry, and we
count it and store the result in the local nr_rules variable. But we
don't need to do so; since the array is a constant, we can compute its
size directly. The original code probably didn't do that because it was
written as part of for-each-ref, and saw the array only as a pointer. It
was migrated in 7c2b3029df (make get_short_ref a public function,
2009-04-07) and could have been updated then, but that subtlety was not
noticed.
We even have a constant that represents this value already, courtesy of
60650a48c0 (remote: make refspec follow the same disambiguation rule as
local refs, 2018-08-01), though again, nobody noticed at the time that
it could be used here, too.
The current count-up isn't a big deal, as we need to preprocess that
array anyway. But it will become more cumbersome as we refactor the
shortening code. So let's get rid of it and just use the constant
everywhere.
Note that there are two things here that aren't just simple text
replacements:
1. We also use nr_rules to see if a previous call has initialized the
static pre-processing variables. We can just use the scanf_fmts
pointer to do the same thing, as it is non-NULL only after we've
done that initialization.
2. If nr_rules is zero after we've counted it up, we bail from the
function. This code is unreachable, though, as the set of rules is
hard-coded and non-empty. And that becomes even more apparent now
that we are using the constant. So we can drop this conditional
completely (and ironically, the code would have the same output if
it _did_ trigger, as we'd simply skip the loop entirely and return
the whole refname).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We parse the shortened name "foo" out of the full refname
"refs/heads/foo", and then assign the result of strlen(short_name) to an
int, which may truncate or wrap to negative.
In practice, this should never happen, as it requires a 2GB refname. And
even somebody trying to do something malicious should at worst end up
with a confused answer (we use the size only to feed back as a
placeholder length to strbuf_addf() to see if there are any collisions
in the lookup rules).
And it may even be impossible to trigger this, as we parse the string
with sscanf(), and stdio formatting functions are not known for handling
large strings well. I didn't test, but I wouldn't be surprised if
sscanf() on many platforms simply reports no match here.
But even if it is not a problem in practice so far, it is worth fixing
for two reasons:
1. We'll shortly be replacing the sscanf() call with a real parser
which will handle arbitrary-sized strings.
2. Assigning strlen() to an int is an anti-pattern that requires
people to look twice when auditing for real overflow problems.
So we'll make this a size_t. Unfortunately we still have to cast to int
eventually for the strbuf_addf() call, but at least we can localize the
cast there, and check that it will be valid. I used our new cast helper
here, which will just bail completely. That should be OK, as anybody
with a 2GB refname is up to no good, but if we really wanted to, we
could detect it manually and just refuse to shorten the refname.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The ls_refs() function (for the v2 protocol command of the same name)
takes a repository parameter (like all v2 commands), but ignores it. It
should use it to access the refs.
This isn't a bug in practice, since we only call this function when
serving upload-pack from the main repository. But it's an awkward
gotcha, and it causes -Wunused-parameter to complain.
The main reason we don't use the repository parameter is that the ref
iteration interface we call doesn't have a "refs_" variant that takes a
ref_store. However we can easily add one. In fact, since there is only
one other caller (in ref-filter.c), there is no need to maintain the
non-repository wrapper; that caller can just use the_repository. It's
still a long way from consistently using a repository object, but it's
one small step in the right direction.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We're about to add a new argument to git-rev-list(1) that allows it to
add all references that are visible when taking `transfer.hideRefs` et
al into account. This will require us to potentially parse multiple sets
of hidden refs, which is not easily possible right now as there is only
a single, global instance of the list of parsed hidden refs.
Refactor `parse_hide_refs_config()` and `ref_is_hidden()` so that both
take the list of hidden references as input and adjust callers to keep a
local list, instead. This allows us to easily use multiple hidden-ref
lists. Furthermore, it allows us to properly free this list before we
exit.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
When parsing the hideRefs configuration, we first duplicate the config
value so that we can modify it. We then subsequently append it to the
`hide_refs` string list, which is initialized with `strdup_strings`
enabled. As a consequence we again reallocate the string, but never
free the first duplicate and thus have a memory leak.
While we never clean up the static `hide_refs` variable anyway, this is
no excuse to make the leak worse by leaking every value twice. We are
also about to change the way this variable will be handled so that we do
indeed start to clean it up. So let's fix the memory leak by using the
`string_list_append_nodup()` so that we pass ownership of the allocated
string to `hide_refs`.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
The logic to handle worktree refs (worktrees/NAME/REF and
main-worktree/REF) existed in two places:
* ref_type() in refs.c
* parse_worktree_ref() in worktree.c
Collapse this logic together in one function parse_worktree_ref():
this avoids having to cross-check the result of parse_worktree_ref()
and ref_type().
Introduce enum ref_worktree_type, which is slightly different from
enum ref_type. The latter is a misleading name (one would think that
'ref_type' would have the symref option).
Instead, enum ref_worktree_type only makes explicit how a refname
relates to a worktree. From this point of view, HEAD and
refs/bisect/abc are the same: they specify the current worktree
implicitly.
The files-backend must avoid packing refs/bisect/* and friends into
packed-refs, so expose is_per_worktree_ref() separately.
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Undoes 'jk/unused-annotation' topic and redoes it to work around
Coccinelle rules misfiring false positives in unrelated codepaths.
* ab/unused-annotation:
git-compat-util.h: use "deprecated" for UNUSED variables
git-compat-util.h: use "UNUSED", not "UNUSED(var)"
Annotate function parameters that are not used (but cannot be
removed for structural reasons), to prepare us to later compile
with -Wunused warning turned on.
* jk/unused-annotation:
is_path_owned_by_current_uid(): mark "report" parameter as unused
run-command: mark unused async callback parameters
mark unused read_tree_recursive() callback parameters
hashmap: mark unused callback parameters
config: mark unused callback parameters
streaming: mark unused virtual method parameters
transport: mark bundle transport_options as unused
refs: mark unused virtual method parameters
refs: mark unused reflog callback parameters
refs: mark unused each_ref_fn parameters
git-compat-util: add UNUSED macro
As reported in [1] the "UNUSED(var)" macro introduced in
2174b8c75d (Merge branch 'jk/unused-annotation' into next,
2022-08-24) breaks coccinelle's parsing of our sources in files where
it occurs.
Let's instead partially go with the approach suggested in [2] of
making this not take an argument. As noted in [1] "coccinelle" will
ignore such tokens in argument lists that it doesn't know about, and
it's less of a surprise to syntax highlighters.
This undoes the "help us notice when a parameter marked as unused is
actually use" part of 9b24034754 (git-compat-util: add UNUSED macro,
2022-08-19), a subsequent commit will further tweak the macro to
implement a replacement for that functionality.
1. https://lore.kernel.org/git/220825.86ilmg4mil.gmgdl@evledraar.gmail.com/
2. https://lore.kernel.org/git/220819.868rnk54ju.gmgdl@evledraar.gmail.com/
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Hashmap comparison functions must conform to a particular callback
interface, but many don't use all of their parameters. Especially the
void cmp_data pointer, but some do not use keydata either (because they
can easily form a full struct to pass when doing lookups). Let's mark
these to make -Wunused-parameter happy.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Functions used with for_each_reflog_ent() need to conform to a
particular interface, but not every function needs all of the
parameters. Mark the unused ones to make -Wunused-parameter happy.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Functions used with for_each_ref(), etc, need to conform to the
each_ref_fn interface. But most of them don't need every parameter;
let's annotate the unused ones to quiet -Wunused-parameter.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The git_replace_ref_base global is used to store the value of the
GIT_REPLACE_REF_BASE environment variable or the default of
"refs/replace/". This is initialized within setup_git_env().
The ref_namespaces array is a new centralized location for information
such as the ref namespace used for replace refs. Instead of having this
namespace stored in two places, use the ref_namespaces array instead.
For simplicity, create a local git_replace_ref_base variable wherever
the global was previously used.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git interprets different meanings to different refs based on their
names. Some meanings are cosmetic, like how refs in 'refs/remotes/*'
are colored differently from refs in 'refs/heads/*'. Others are more
critical, such as how replace refs are interpreted.
Before making behavior changes based on ref namespaces, collect all
known ref namespaces into a array of ref_namespace_info structs. This
array is indexed by the new ref_namespace enum for quick access.
As of this change, this array is purely documentation. Future changes
will add dependencies on this array.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The normalize_glob_ref() method was introduced in 65516f586b (log:
add option to choose which refs to decorate, 2017-11-21) to help with
decoration filters such as --decorate-refs=<filter> and
--decorate-refs-exclude=<filter>. The method has not been used anywhere
else.
At the moment, it is impossible to specify HEAD as a decoration filter
since normalize_glob_ref() prepends "refs/" to the filter if it isn't
already there.
Allow adding HEAD as a decoration filter by allowing the exact string
"HEAD" to not be prepended with "refs/". Add a test in t4202-log.sh that
would previously fail since the HEAD decoration would exist in the
output.
It is sufficient to only cover "HEAD" here and not include other special
refs like REBASE_HEAD. This is because HEAD is the only ref outside of
refs/* that is added to the list of decorations. However, we may want to
special-case these other refs in normalize_glob_ref() in the future.
Leave a NEEDSWORK comment for now.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When cloning directly from a local repository, we load a list of refs
based on scanning the $GIT_DIR/refs/ directory of the "server"
repository. If files exist in that directory that do not parse as
hexadecimal hashes, then the ref array used by write_remote_refs()
ends up with some entries with null OIDs. This causes us to hit a BUG()
statement in ref_transaction_create():
BUG: create called without valid new_oid
This BUG() call used to be a die() until 033abf97f (Replace all
die("BUG: ...") calls by BUG() ones, 2018-05-02). Before that, the die()
was added by f04c5b552 (ref_transaction_create(): check that new_sha1 is
valid, 2015-02-17).
The original report for this bug [1] mentioned that this problem did not
exist in Git 2.27.0. The failure bisects unsurprisingly to 968f12fda
(refs: turn on GIT_REF_PARANOIA by default, 2021-09-24). When
GIT_REF_PARANOIA is enabled, this case always fails as far back as I am
able to successfully compile and test the Git codebase.
[1] https://github.com/git-for-windows/git/issues/3781
There are two approaches to consider here. One would be to remove this
BUG() statement in favor of returning with an error. There are only two
callers to ref_transaction_create(), so this would have a limited
impact.
The other approach would be to add special casing in 'git clone' to
avoid this faulty input to the method.
While I originally started with changing 'git clone', I decided that
modifying ref_transaction_create() was a more complete solution. This
prevents failing with a BUG() statement when we already have a good way
to report an error (including a reason for that error) within the
method. Both callers properly check the return value and die() with the
error message, so this is an appropriate direction.
The added test helps check against a regression, but does check that our
intended error message is handled correctly.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In cd475b3b03 (refs: add ability for backends to special-case reading
of symbolic refs, 2022-03-01) when the "read_symbolic_ref" callback
was added we'd fall back on "refs_read_raw_ref" if there wasn't any
backend implementation of "read_symbolic_ref".
As discussed in the preceding commit this would only happen if we were
running the "debug" backend, e.g. in the "setup for ref completion"
test in t9902-completion.sh with:
GIT_TRACE_REFS=1 git fetch --no-tags other
Let's improve the trace output, but and also eliminate the
now-redundant refs_read_raw_ref() fallback case. As noted in the
preceding commit the "packed" backend will never call
refs_read_symbolic_ref() (nor is it ever going to). For any future
backend such as reftable it's OK to ask that they either implement
this (or a wrapper) themselves.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Various optimization for "git fetch".
* ps/fetch-mirror-optim:
refs/files-backend: optimize reading of symbolic refs
remote: read symbolic refs via `refs_read_symbolic_ref()`
refs: add ability for backends to special-case reading of symbolic refs
fetch: avoid lookup of commits when not appending to FETCH_HEAD
upload-pack: look up "want" lines via commit-graph
"git fetch" can make two separate fetches, but ref updates coming
from them were in two separate ref transactions under "--atomic",
which has been corrected.
* ps/fetch-atomic:
fetch: make `--atomic` flag cover pruning of refs
fetch: make `--atomic` flag cover backfilling of tags
refs: add interface to iterate over queued transactional updates
fetch: report errors when backfilling tags fails
fetch: control lifecycle of FETCH_HEAD in a single place
fetch: backfill tags before setting upstream
fetch: increase test coverage of fetches
Reading of symbolic and non-symbolic references is currently treated the
same in reference backends: we always call `refs_read_raw_ref()` and
then decide based on the returned flags what type it is. This has one
downside though: symbolic references may be treated different from
normal references in a backend from normal references. The packed-refs
backend for example doesn't even know about symbolic references, and as
a result it is pointless to even ask it for one.
There are cases where we really only care about whether a reference is
symbolic or not, but don't care about whether it exists at all or may be
a non-symbolic reference. But it is not possible to optimize for this
case right now, and as a consequence we will always first check for a
loose reference to exist, and if it doesn't, we'll query the packed-refs
backend for a known-to-not-be-symbolic reference. This is inefficient
and requires us to search all packed references even though we know to
not care for the result at all.
Introduce a new function `refs_read_symbolic_ref()` which allows us to
fix this case. This function will only ever return symbolic references
and can thus optimize for the scenario layed out above. By default, if
the backend doesn't provide an implementation for it, we just use the
old code path and fall back to `read_raw_ref()`. But in case the backend
provides its own, more efficient implementation, we will use that one
instead.
Note that this function is explicitly designed to not distinguish
between missing references and non-symbolic references. If it did, we'd
be forced to always search the packed-refs backend to see whether the
symbolic reference the user asked for really doesn't exist, or if it
exists as a non-symbolic reference.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* ps/fetch-atomic:
fetch: make `--atomic` flag cover pruning of refs
fetch: make `--atomic` flag cover backfilling of tags
refs: add interface to iterate over queued transactional updates
fetch: report errors when backfilling tags fails
fetch: control lifecycle of FETCH_HEAD in a single place
fetch: backfill tags before setting upstream
fetch: increase test coverage of fetches
Plug (some) memory leaks around parse_date_format().
* ab/date-mode-release:
date API: add and use a date_mode_release()
date API: add basic API docs
date API: provide and use a DATE_MODE_INIT
date API: create a date.h, split from cache.h
cache.h: remove always unused show_date_human() declaration
Because a deletion of ref would need to remove it from both the
loose ref store and the packed ref store, a delete-ref operation
that logically removes one ref may end up invoking ref-transaction
hook twice, which has been corrected.
* ps/avoid-unnecessary-hook-invocation-with-packed-refs:
refs: skip hooks when deleting uncovered packed refs
refs: do not execute reference-transaction hook on packing refs
refs: demonstrate excessive execution of the reference-transaction hook
refs: allow skipping the reference-transaction hook
refs: allow passing flags when beginning transactions
refs: extract packed_refs_delete_refs() to allow control of transaction
There is no way for a caller to see whether a reference update has
already been queued up for a given reference transaction. There are
multiple alternatives to provide this functionality:
- We may add a function that simply tells us whether a specific
reference has already been queued. If implemented naively then
this would potentially be quadratic in runtime behaviour if this
question is asked repeatedly because we have to iterate over all
references every time. The alternative would be to add a hashmap
of all queued reference updates to speed up the lookup, but this
adds overhead to all callers.
- We may add a flag to `ref_transaction_add_update()` that causes it
to skip duplicates, but this has the same runtime concerns as the
first alternative.
- We may add an interface which lets callers collect all updates
which have already been queued such that he can avoid re-adding
them. This is the most flexible approach and puts the burden on
the caller, but also allows us to not impact any of the existing
callsites which don't need this information.
This commit implements the last approach: it allows us to compute the
map of already-queued updates once up front such that we can then skip
all subsequent references which are already part of this map.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move the declaration of the date.c functions from cache.h, and adjust
the relevant users to include the new date.h header.
The show_ident_date() function belonged in pretty.h (it's defined in
pretty.c), its two users outside of pretty.c didn't strictly need to
include pretty.h, as they get it indirectly, but let's add it to them
anyway.
Similarly, the change to "builtin/{fast-import,show-branch,tag}.c"
isn't needed as far as the compiler is concerned, but since they all
use the "DATE_MODE()" macro we now define in date.h, let's have them
include it.
We could simply include this new header in "cache.h", but as this
change shows these functions weren't common enough to warrant
including in it in the first place. By moving them out of cache.h
changes to this API will no longer cause a (mostly) full re-build of
the project when "make" is run.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remove the now-unused "failure_errno" parameter from the
refs_resolve_ref_unsafe() signature. In my recent 96f6623ada (Merge
branch 'ab/refs-errno-cleanup', 2021-11-29) series we made all of its
callers explicitly request the errno via an output parameter.
As that series shows all but one caller ended up passing in a
boilerplate "ignore_errno", since they only cared about whether the
return value was NULL or not, i.e. if the ref could be resolved.
There was one small issue with that series fixed with a follow-up in
31e3912369 (Merge branch 'ab/refs-errno-cleanup', 2022-01-14) a small
bug in that series was fixed.
After those two there was one caller left in sequencer.c that used the
"failure_errno', but as of the preceding commit it uses a boilerplate
"ignore_errno" instead.
This leaves the public refs API without any use of "failure_errno" at
all. We could still do with a bit of cleanup and generalization
between refs.c and refs/files-backend.c before the "reftable"
integration lands, but that's all internal to the reference code
itself.
So let's remove this output parameter. Not only isn't it used now, but
it's unlikely that we'll want it again in the future. We'd like to
slowly move the refs API to a more file-backend independent way of
communicating error codes, having it use a "failure_errno" was only
the first step in that direction. If this or any other function needs
to communicate what specifically is wrong with the requested "refname"
it'll be better to have the function set some output enum of
well-defined error states than piggy-backend on "errno".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The reference-transaction hook is executing whenever we prepare, commit
or abort a reference transaction. While this is mostly intentional, in
case of the files backend we're leaking the implementation detail that
the store is in fact a composite store with one loose and one packed
backend to the caller. So while we want to execute the hook for all
logical updates, executing it for such implementation details is
unexpected.
Prepare for a fix by adding a new flag which allows to skip execution of
the hook.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We do not currently have any flags when creating reference transactions,
but we'll add one to disable execution of the reference transaction hook
in some cases.
Allow passing flags to `ref_store_transaction_begin()` to prepare for
this change.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix a logic error in refs_resolve_ref_unsafe() introduced in a recent
series of mine to abstract the refs API away from errno. See
96f6623ada (Merge branch 'ab/refs-errno-cleanup', 2021-11-29)for that
series.
In that series introduction of "failure_errno" to
refs_resolve_ref_unsafe came in ef18119dec (refs API: add a version
of refs_resolve_ref_unsafe() with "errno", 2021-10-16). There we'd set
"errno = 0" immediately before refs_read_raw_ref(), and then set
"failure_errno" to "errno" if errno was non-zero afterwards.
Then in the next commit 8b72fea7e9 (refs API: make
refs_read_raw_ref() not set errno, 2021-10-16) we started expecting
"refs_read_raw_ref()" to set "failure_errno". It would do that if
refs_read_raw_ref() failed, but it wouldn't be the same errno.
So we might set the "errno" here to any arbitrary bad value, and end
up e.g. returning NULL when we meant to return the refname from
refs_resolve_ref_unsafe(), or the other way around. Instrumenting this
code will reveal cases where refs_read_raw_ref() will fail, and
"errno" and "failure_errno" will be set to different values.
In practice I haven't found a case where this scary bug changed
anything in practice. The reason for that is that we'll not care about
the actual value of "errno" here per-se, but only whether:
1. We have an errno
2. If it's one of ENOENT, EISDIR or ENOTDIR. See the adjacent code
added in a1c1d8170d (refs_resolve_ref_unsafe: handle d/f
conflicts for writes, 2017-10-06)
I.e. if we clobber "failure_errno" with "errno", but it happened to be
one of those three, and we'll clobber it with another one of the three
we were OK.
Perhaps there are cases where the difference ended up mattering, but I
haven't found them. Instrumenting the test suite to fail if "errno"
and "failure_errno" are different shows a lot of failures, checking if
they're different *and* one is but not the other is outside that list
of three "errno" values yields no failures.
But let's fix the obvious bug. We should just stop paying attention to
"errno" in refs_resolve_ref_unsafe(). In addition let's change the
partial resetting of "errno" in files_read_raw_ref() to happen just
before the "return", to ensure that any such bug will be more easily
spotted in the future.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Debugging support for refs API.
* hn/refs-debug-update:
refs: centralize initialization of the base ref_store.
refs: print error message in debug output
refs: pass gitdir to packed_ref_store_create
New interface into the tmp-objdir API to help in-core use of the
quarantine feature.
* ns/tmp-objdir:
tmp-objdir: disable ref updates when replacing the primary odb
tmp-objdir: new API for creating temporary writable databases
John Cai
Elijah Newren
Junio C Hamano
Ævar Arnfjörð Bjarmason
Jeff King
Patrick Steinhardt
Han-Wen Nienhuys
Derrick Stolee