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2025-11-04refs: drop infrastructure to peel via iteratorsPatrick Steinhardt1-9/+0
Now that the peeled object ID gets propagated via the `struct reference` there is no need anymore to call into the reference iterator itself to dereference an object. Remove this infrastructure. Most of the changes are straight-forward deletions of code. There is one exception though in `refs/packed-backend.c::write_with_updates()`. Here we stop peeling the iterator and instead just pass the peeled object ID of that iterator directly. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-11-04refs: fully reset `struct ref_iterator::ref` on iterationPatrick Steinhardt1-0/+1
With the introduction of the `struct ref_iterator::ref` field it now is a whole lot easier to introduce new fields that become accessible to the caller without having to adapt every single callsite. But there's a downside: when a new field is introduced we always have to adapt all backends to set that field. This isn't something we can avoid in the general case: when the new field is expected to be populated by all backends we of course cannot avoid doing so. But new fields may be entirely optional, in which case we'd still have such churn. And furthermore, it is very easy right now to leak state from a previous iteration into the next iteration. Address this issue by ensuring that the reference backends all fully reset the field on every single iteration. This ensures that no state from previous iterations can leak into the next one. And it ensures that any newly introduced fields will be zeroed out by default. Note that we don't have to explicitly adapt the "files" backend, as it uses the `cache_ref_iterator` internally. Furthermore, other "wrapping" iterators like for example the `prefix_ref_iterator` copy around the whole reference, so these don't need to be adapted either. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-11-04refs: introduce `.ref` field for the base iteratorPatrick Steinhardt1-5/+5
The base iterator has a couple of fields that tracks the name, target, object ID and flags for the current reference. Due to this design we have to create a new `struct reference` whenever we want to hand over that reference to the callback function, which is tedious and not very efficient. Convert the structure to instead contain a `struct reference` as member. This member is expected to be populated by the implementations of the iterator and is handed over to the callback directly. While at it, simplify `should_pack_ref()` to take a `struct reference` directly instead of passing its respective fields. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-10-01refs/ref-cache: fix SEGFAULT when seeking in empty directoriesKarthik Nayak1-1/+1
The 'cache_ref_iterator_seek()' function is used to seek the `ref_iterator` to the desired reference in the ref-cache mechanism. We use the seeking functionality to implement the '--start-after' flag in 'git-for-each-ref(1)'. When using the files-backend with packed-refs, it is possible that some of the refs directories are empty. For e.g. just after repacking, the 'refs/heads' directory would be empty. The ref-cache seek mechanism, doesn't take this into consideration when descending into a subdirectory, and makes an out of bounds access, causing SEGFAULT as we try to access entries within the directory. Fix this by breaking out of the loop when we enter an empty directory. Since we start with the base directory of 'refs/' which is never empty, it is okay to perform this check after the first iteration in the `do..while` clause. Add tests which simulate this behavior and also provide coverage over using the feature over packed-refs. Helped-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Karthik Nayak <karthik.188@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-07-28ref-cache: use 'size_t' instead of int for lengthKarthik Nayak1-2/+3
The commit 090eb5336c (refs: selectively set prefix in the seek functions, 2025-07-15) modified the ref-cache iterator to support seeking to a specified marker without setting the prefix. The commit adds and uses an integer 'len' to capture the length of the seek marker to compare with the entries of a given directory. Since the type of the variable is 'int', this is met with a typecast of converting a `strlen` to 'int' so it can be assigned to the 'len' variable. This is whole operation is a bit wrong: 1. Since the 'len' variable is eventually used in a 'strncmp', it should have been of type 'size_t'. 2. This also truncates the value provided from 'strlen' to an int, which could cause a large refname to produce a negative number. Let's do the correct thing here and simply use 'size_t' for `len`. Signed-off-by: Karthik Nayak <karthik.188@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-07-24ref-cache: set prefix_state when seekingKarthik Nayak1-0/+1
In 090eb5336c (refs: selectively set prefix in the seek functions, 2025-07-15) we separated the seeking functionality of reference iterators from the functionality to set prefix to an iterator. This allows users of ref iterators to seek to a particular reference to provide pagination support. The files-backend, uses the ref-cache iterator to iterate over loose refs. The iterator tracks directories and entries already processed via a stack of levels. Each level corresponds to a directory under the files backend. New levels are added to the stack, and when all entries from a level is yielded, the corresponding level is popped from the stack. To accommodate seeking, we need to populate and traverse the levels to stop the requested seek marker at the appropriate level and its entry index. Each level also contains a 'prefix_state' which is used for prefix matching, this allows the iterator to skip levels/entries which don't match a prefix. The default value of 'prefix_state' is PREFIX_CONTAINS_DIR, which yields all entries within a level. When purely seeking without prefix matching, we want to yield all entries. The commit however, skips setting the value explicitly. This causes the MemorySanitizer to issue a 'use-of-uninitialized-value' error when running 't/t6302-for-each-ref-filter'. Set the value explicitly to avoid to fix the issue. Reported-by: Kyle Lippincott <spectral@google.com> Helped-by: Kyle Lippincott <spectral@google.com> Helped-by: Jeff King <peff@peff.net> Signed-off-by: Karthik Nayak <karthik.188@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-07-15refs: selectively set prefix in the seek functionsKarthik Nayak1-5/+80
The ref iterator exposes a `ref_iterator_seek()` function. The name suggests that this would seek the iterator to a specific reference in some ways similar to how `fseek()` works for the filesystem. However, the function actually sets the prefix for refs iteration. So further iteration would only yield references which match the particular prefix. This is a bit confusing. Let's add a 'flags' field to the function, which when set with the 'REF_ITERATOR_SEEK_SET_PREFIX' flag, will set the prefix for the iteration in-line with the existing behavior. Otherwise, the reference backends will simply seek to the specified reference and clears any previously set prefix. This allows users to start iteration from a specific reference. In the packed and reftable backend, since references are available in a sorted list, the changes are simply setting the prefix if needed. The changes on the files-backend are a little more involved, since the files backend uses the 'ref-cache' mechanism. We move out the existing logic within `cache_ref_iterator_seek()` to `cache_ref_iterator_set_prefix()` which is called when the 'REF_ITERATOR_SEEK_SET_PREFIX' flag is set. We then parse the provided seek string and set the required levels and their indexes to ensure that seeking is possible. Helped-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Karthik Nayak <karthik.188@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-07-15ref-cache: remove unused function 'find_ref_entry()'Karthik Nayak1-14/+0
The 'find_ref_entry' function is no longer used, so remove it. Signed-off-by: Karthik Nayak <karthik.188@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-03-12refs/iterator: implement seeking for ref-cache iteratorsPatrick Steinhardt1-28/+51
Implement seeking of ref-cache iterators. This is done by splitting most of the logic to seek iterators out of `cache_ref_iterator_begin()` and putting it into `cache_ref_iterator_seek()` so that we can reuse the logic. Note that we cannot use the optimization anymore where we return an empty ref iterator when there aren't any references, as otherwise it wouldn't be possible to reseek the iterator to a different prefix that may exist. This shouldn't be much of a performance concern though as we now start to bail out early in case `advance()` sees that there are no more directories to be searched. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-03-12refs/iterator: separate lifecycle from iterationPatrick Steinhardt1-6/+3
The ref and reflog iterators have their lifecycle attached to iteration: once the iterator reaches its end, it is automatically released and the caller doesn't have to care about that anymore. When the iterator should be released before it has been exhausted, callers must explicitly abort the iterator via `ref_iterator_abort()`. This lifecycle is somewhat unusual in the Git codebase and creates two problems: - Callsites need to be very careful about when exactly they call `ref_iterator_abort()`, as calling the function is only valid when the iterator itself still is. This leads to somewhat awkward calling patterns in some situations. - It is impossible to reuse iterators and re-seek them to a different prefix. This feature isn't supported by any iterator implementation except for the reftable iterators anyway, but if it was implemented it would allow us to optimize cases where we need to search for specific references repeatedly by reusing internal state. Detangle the lifecycle from iteration so that we don't deallocate the iterator anymore once it is exhausted. Instead, callers are now expected to always call a newly introduce `ref_iterator_free()` function that deallocates the iterator and its internal state. Note that the `dir_iterator` is somewhat special because it does not implement the `ref_iterator` interface, but is only used to implement other iterators. Consequently, we have to provide `dir_iterator_free()` instead of `dir_iterator_release()` as the allocated structure itself is managed by the `dir_iterator` interfaces, as well, and not freed by `ref_iterator_free()` like in all the other cases. While at it, drop the return value of `ref_iterator_abort()`, which wasn't really required by any of the iterator implementations anyway. Furthermore, stop calling `base_ref_iterator_free()` in any of the backends, but instead call it in `ref_iterator_free()`. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-27ref-cache: fix invalid free operation in `free_ref_entry`shejialuo1-1/+2
In cfd971520e (refs: keep track of unresolved reference value in iterators, 2024-08-09), we added a new field "referent" into the "struct ref" structure. In order to free the "referent", we unconditionally freed the "referent" by simply adding a "free" statement. However, this is a bad usage. Because when ref entry is either directory or loose ref, we will always execute the following statement: free(entry->u.value.referent); This does not make sense. We should never access the "entry->u.value" field when "entry" is a directory. However, the change obviously doesn't break the tests. Let's analysis why. The anonymous union in the "ref_entry" has two members: one is "struct ref_value", another is "struct ref_dir". On a 64-bit machine, the size of "struct ref_dir" is 32 bytes, which is smaller than the 48-byte size of "struct ref_value". And the offset of "referent" field in "struct ref_value" is 40 bytes. So, whenever we create a new "ref_entry" for a directory, we will leave the offset from 40 bytes to 48 bytes untouched, which means the value for this memory is zero (NULL). It's OK to free a NULL pointer, but this is merely a coincidence of memory layout. To fix this issue, we now ensure that "free(entry->u.value.referent)" is only called when "entry->flag" indicates that it represents a loose reference and not a directory to avoid the invalid memory operation. Signed-off-by: shejialuo <shejialuo@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-09refs: keep track of unresolved reference value in iteratorsJohn Cai1-0/+5
Since ref iterators do not hold onto the direct value of a reference without resolving it, the only way to get ahold of a direct value of a symbolic ref is to make a separate call to refs_read_symbolic_ref. To make accessing the direct value of a symbolic ref more efficient, let's save the direct value of the ref in the iterators for both the files backend and the reftable backend. Signed-off-by: John Cai <johncai86@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06refs/files: fix NULL pointer deref when releasing ref storePatrick Steinhardt1-0/+2
The `free_ref_cache()` function is not `NULL` safe and will thus segfault when being passed such a pointer. This can easily happen when trying to release a partially initialized "files" ref store. Fix this. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-17refs: pass repo when peeling objectsPatrick Steinhardt1-4/+1
Both `peel_object()` and `peel_iterated_oid()` implicitly rely on `the_repository` to look up objects. Despite the fact that we want to get rid of `the_repository`, it also leads to some restrictions in our ref iterators when trying to retrieve the peeled value for a repository other than `the_repository`. Refactor these functions such that both take a repository as argument and remove the now-unnecessary restrictions. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-02-21refs: always treat iterators as orderedPatrick Steinhardt1-1/+1
In the preceding commit we have converted the reflog iterator of the "files" backend to be ordered, which was the only remaining ref iterator that wasn't ordered. Refactor the ref iterator infrastructure so that we always assume iterators to be ordered, thus simplifying the code. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-26treewide: remove unnecessary includes in source filesElijah Newren1-1/+0
Each of these were checked with gcc -E -I. ${SOURCE_FILE} | grep ${HEADER_FILE} to ensure that removing the direct inclusion of the header actually resulted in that header no longer being included at all (i.e. that no other header pulled it in transitively). ...except for a few cases where we verified that although the header was brought in transitively, nothing from it was directly used in that source file. These cases were: * builtin/credential-cache.c * builtin/pull.c * builtin/send-pack.c Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-10-09ref-cache.c: fix prefix matching in ref iterationVictoria Dye1-1/+2
Update 'cache_ref_iterator_advance' to skip over refs that are not matched by the given prefix. Currently, a ref entry is considered "matched" if the entry name is fully contained within the prefix: * prefix: "refs/heads/v1" * entry: "refs/heads/v1.0" OR if the prefix is fully contained in the entry name: * prefix: "refs/heads/v1.0" * entry: "refs/heads/v1" The first case is always correct, but the second is only correct if the ref cache entry is a directory, for example: * prefix: "refs/heads/example" * entry: "refs/heads/" Modify the logic in 'cache_ref_iterator_advance' to reflect these expectations: 1. If 'overlaps_prefix' returns 'PREFIX_EXCLUDES_DIR', then the prefix and ref cache entry do not overlap at all. Skip this entry. 2. If 'overlaps_prefix' returns 'PREFIX_WITHIN_DIR', then the prefix matches inside this entry if it is a directory. Skip if the entry is not a directory, otherwise iterate over it. 3. Otherwise, 'overlaps_prefix' returned 'PREFIX_CONTAINS_DIR', indicating that the cache entry (directory or not) is fully contained by or equal to the prefix. Iterate over this entry. Note that condition 2 relies on the names of directory entries having the appropriate trailing slash. The existing function documentation of 'create_dir_entry' explicitly calls out the trailing slash requirement, so this is a safe assumption to make. This bug generally doesn't have any user-facing impact, since it requires: 1. using a non-empty prefix without a trailing slash in an iteration like 'for_each_fullref_in', 2. the callback to said iteration not reapplying the original filter (as for-each-ref does) to ensure unmatched refs are skipped, and 3. the repository having one or more refs that match part of, but not all of, the prefix. However, there are some niche scenarios that meet those criteria (specifically, 'rev-parse --bisect' and '(log|show|shortlog) --bisect'). Add tests covering those cases to demonstrate the fix in this patch. Signed-off-by: Victoria Dye <vdye@github.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-04-24hash-ll.h: split out of hash.h to remove dependency on repository.hElijah Newren1-0/+2
hash.h depends upon and includes repository.h, due to the definition and use of the_hash_algo (defined as the_repository->hash_algo). However, most headers trying to include hash.h are only interested in the layout of the structs like object_id. Move the parts of hash.h that do not depend upon repository.h into a new file hash-ll.h (the "low level" parts of hash.h), and adjust other files to use this new header where the convenience inline functions aren't needed. This allows hash.h and object.h to be fairly small, minimal headers. It also exposes a lot of hidden dependencies on both path.h (which was brought in by repository.h) and repository.h (which was previously implicitly brought in by object.h), so also adjust other files to be more explicit about what they depend upon. Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-23alloc.h: move ALLOC_GROW() functions from cache.hElijah Newren1-1/+2
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>
2022-05-20Merge branch 'ep/maint-equals-null-cocci'Junio C Hamano1-1/+1
Introduce and apply coccinelle rule to discourage an explicit comparison between a pointer and NULL, and applies the clean-up to the maintenance track. * ep/maint-equals-null-cocci: tree-wide: apply equals-null.cocci tree-wide: apply equals-null.cocci contrib/coccinnelle: add equals-null.cocci
2022-05-02tree-wide: apply equals-null.cocciJunio C Hamano1-1/+1
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-17refs: use designated initializers for "struct ref_iterator_vtable"Ævar Arnfjörð Bjarmason1-3/+3
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-25Merge branch 'jt/no-abuse-alternate-odb-for-submodules'Junio C Hamano1-0/+10
Follow through the work to use the repo interface to access submodule objects in-process, instead of abusing the alternate object database interface. * jt/no-abuse-alternate-odb-for-submodules: submodule: trace adding submodule ODB as alternate submodule: pass repo to check_has_commit() object-file: only register submodule ODB if needed merge-{ort,recursive}: remove add_submodule_odb() refs: peeling non-the_repository iterators is BUG refs: teach arbitrary repo support to iterators refs: plumb repo into ref stores
2021-10-08refs: peeling non-the_repository iterators is BUGJonathan Tan1-0/+10
There is currently no support for peeling the current ref of an iterator iterating over a non-the_repository ref store, and none is needed. Thus, for now, BUG() if that happens. Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28refs/ref-cache.[ch]: remove "incomplete" from create_dir_entry()Ævar Arnfjörð Bjarmason1-4/+3
Remove the now-unused "incomplete" parameter from create_dir_entry(), all its callers specify it as "1", so let's drop the "incomplete=0" case. The last caller to use it was search_for_subdir(), but that code was removed in the preceding commit. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28refs/ref-cache.c: remove "mkdir" parameter from find_containing_dir()Ævar Arnfjörð Bjarmason1-24/+12
Remove the "mkdir" parameter from the find_containing_dir() function, the add_ref_entry() function removed in the preceding commit was its last user. Since "mkdir" is always "0" we can also remove the parameter from search_for_subdir(), which in turn means that we can delete most of that function. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28refs/ref-cache.[ch]: remove unused add_ref_entry()Ævar Arnfjörð Bjarmason1-9/+0
This function has not been used since 9dd389f3d8d (packed_ref_store: get rid of the `ref_cache` entirely, 2017-09-25). Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28refs/ref-cache.[ch]: remove unused remove_entry_from_dir()Ævar Arnfjörð Bjarmason1-35/+0
This function was missed in 9939b33d6a3 (packed-backend: rip out some now-unused code, 2017-09-08), and has been orphaned since then. Let's delete it. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-20refs: make explicit that ref_iterator_peel returns booleanHan-Wen Nienhuys1-1/+1
Use -1 as error return value throughout. This removes spurious differences in the GIT_TRACE_REFS output, depending on the ref storage backend active. Before, the cached ref_iterator (but only that iterator!) would return peel_object() output directly. No callers relied on the peel_status values beyond success/failure. All calls to these functions go through peel_iterated_oid(), which returns peel_object() as a fallback, but also squashing the error values. The iteration interface already passes REF_ISSYMREF and REF_ISBROKEN through the flags argument, so the additional error values in enum peel_status provide no value. The ref iteration interface provides a separate peel() function because certain formats (eg. packed-refs and reftable) can store the peeled object next to the tag SHA1. Passing the peeled SHA1 as an optional argument to each_ref_fn maps more naturally to the implementation of ref databases. Changing the code in this way is left for a future refactoring. Signed-off-by: Han-Wen Nienhuys <hanwen@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-13use CALLOC_ARRAYRené Scharfe1-1/+1
Add and apply a semantic patch for converting code that open-codes CALLOC_ARRAY to use it instead. It shortens the code and infers the element size automatically. Signed-off-by: René Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-29convert "oidcmp() != 0" to "!oideq()"Jeff King1-1/+1
This is the flip side of the previous two patches: checking for a non-zero oidcmp() can be more strictly expressed as inequality. Like those patches, we write "!= 0" in the coccinelle transformation, which covers by isomorphism the more common: if (oidcmp(E1, E2)) As with the previous two patches, this patch can be achieved almost entirely by running "make coccicheck"; the only differences are manual line-wrap fixes to match the original code. There is one thing to note for anybody replicating this, though: coccinelle 1.0.4 seems to miss the case in builtin/tag.c, even though it's basically the same as all the others. Running with 1.0.7 does catch this, so presumably it's just a coccinelle bug that was fixed in the interim. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-06Replace all die("BUG: ...") calls by BUG() onesJohannes Schindelin1-1/+1
In d8193743e08 (usage.c: add BUG() function, 2017-05-12), a new macro was introduced to use for reporting bugs instead of die(). It was then subsequently used to convert one single caller in 588a538ae55 (setup_git_env: convert die("BUG") to BUG(), 2017-05-12). The cover letter of the patch series containing this patch (cf 20170513032414.mfrwabt4hovujde2@sigill.intra.peff.net) is not terribly clear why only one call site was converted, or what the plan is for other, similar calls to die() to report bugs. Let's just convert all remaining ones in one fell swoop. This trick was performed by this invocation: sed -i 's/die("BUG: /BUG("/g' $(git grep -l 'die("BUG' \*.c) Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-01-22Use MOVE_ARRAYSZEDER Gábor1-4/+2
Use the helper macro MOVE_ARRAY to move arrays. This is shorter and safer, as it automatically infers the size of elements. Patch generated by Coccinelle and contrib/coccinelle/array.cocci in Travis CI's static analysis build job. Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-11-06refs: update some more docs to use "oid" rather than "sha1"Michael Haggerty1-2/+2
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-16refs: convert peel_object to struct object_idbrian m. carlson1-1/+1
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-09-25ref_cache: remove support for storing peeled valuesMichael Haggerty1-41/+1
Now that the `packed-refs` backend doesn't use `ref_cache`, there is nobody left who might want to store peeled values of references in `ref_cache`. So remove that feature. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-09-14ref_iterator: keep track of whether the iterator output is orderedMichael Haggerty1-1/+1
References are iterated over in order by refname, but reflogs are not. Some consumers of reference iteration care about the difference. Teach each `ref_iterator` to keep track of whether its output is ordered. `overlay_ref_iterator` is one of the picky consumers. Add a sanity check in `overlay_ref_iterator_begin()` to verify that its inputs are ordered. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-16*.[ch] refactoring: make use of the FREE_AND_NULL() macroÆvar Arnfjörð Bjarmason1-2/+1
Replace occurrences of `free(ptr); ptr = NULL` which weren't caught by the coccinelle rule. These fall into two categories: - free/NULL assignments one after the other which coccinelle all put on one line, which is functionally equivalent code, but very ugly. - manually spotted occurrences where the NULL assignment isn't right after the free() call. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-24cache_ref_iterator_begin(): avoid priming unneeded directoriesMichael Haggerty1-10/+85
When iterating over references, reference priming is used to make sure that loose references are read into the ref-cache before packed references, to avoid races. It used to be that the prefix passed to reference iterators almost always ended in `/`, for example `refs/heads/`. In that case, the priming code would read all loose references under `find_containing_dir("refs/heads/")`, which is "refs/heads/". That's just what we want. But now that `ref-filter` knows how to pass refname prefixes to `for_each_fullref_in()`, the prefix might come from user input; for example, git for-each-ref refs/heads Since the argument doesn't include a trailing slash, the reference iteration code would prime all of the loose references under `find_containing_dir("refs/heads")`, which is "refs/". Thus we would unnecessarily read tags, remote-tracking references, etc., when the user is only interested in branches. It is a bit awkward to get around this problem. We can't just append a slash to the argument, because we don't know ab initio whether an argument like `refs/tags/release` corresponds to a single tag or to a directory containing tags. Moreover, until now a `prefix_ref_iterator` was used to make the final decision about which references fall within the prefix (the `cache_ref_iterator` only did a rough cut). This is also inefficient, because the `prefix_ref_iterator` can't know, for example, that while you are in a subdirectory that is completely within the prefix, you don't have to do the prefix check. So: * Move the responsibility for doing the prefix check directly to `cache_ref_iterator`. This means that `cache_ref_iterator_begin()` never has to wrap its return value in a `prefix_ref_iterator`. * Teach `cache_ref_iterator_begin()` (and `prime_ref_dir()`) to be stricter about what they iterate over and what directories they prime. * Teach `cache_ref_iterator` to keep track of whether the current `cache_ref_iterator_level` is fully within the prefix. If so, skip the prefix checks entirely. The main benefit of these optimizations is for loose references, since packed references are always read all at once. Note that after this change, `prefix_ref_iterator` is only ever used for its trimming feature and not for its "prefix" feature. But I'm not ripping out the latter yet, because it might be useful for another patch series that I'm working on. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-23create_ref_entry(): remove `check_name` optionMichael Haggerty1-5/+1
Only one caller was using it, so move the check to that caller. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-08refs/files-backend: convert many internals to struct object_idbrian m. carlson1-2/+2
Convert many of the internals of the files backend to use struct object_id. Avoid converting public APIs (except one change to refs/ref-cache.c) to limit the scope of the changes. Convert one use of get_sha1_hex to parse_oid_hex, and rely on the fact that a strbuf will be NUL-terminated and that parse_oid_hex will fail on truncated input to avoid the need to check the length. This is a requirement to convert parse_object later on. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-16do_for_each_entry_in_dir(): delete functionMichael Haggerty1-21/+0
Its only remaining caller was itself. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-16cache_ref_iterator_begin(): make function smarterMichael Haggerty1-4/+34
Change `cache_ref_iterator_begin()` to take two new arguments: * `prefix` -- to iterate only over references with the specified prefix. * `prime_dir` -- to "prime" (i.e., pre-load) the cache before starting the iteration. The new functionality makes it possible for `files_ref_iterator_begin()` to be made more ignorant of the internals of `ref_cache`, and `find_containing_dir()` and `prime_ref_dir()` to be made private. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-16do_for_each_entry_in_dir(): eliminate `offset` argumentMichael Haggerty1-3/+3
It was never used. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-16refs: handle "refs/bisect/" in `loose_fill_ref_dir()`Michael Haggerty1-16/+0
That "refs/bisect/" has to be handled specially when filling the ref_cache for loose references is a peculiarity of the files backend, and the ref-cache code shouldn't need to know about it. So move this code to the callback function, `loose_fill_ref_dir()`. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-16ref-cache: use a callback function to fill the cacheMichael Haggerty1-5/+7
It is a leveling violation for `ref_cache` to know about `files_ref_store` or that it should call `read_loose_refs()` to lazily fill cache directories. So instead, have its constructor take as an argument a callback function that it should use for lazy-filling, and change `files_ref_store` to supply a pointer to function `read_loose_refs` (renamed to `loose_fill_ref_dir`) when creating the ref cache for its loose refs. This means that we can generify the type of the back-pointer in `struct ref_cache` from `files_ref_store` to `ref_store`. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-16refs: record the ref_store in ref_cache, not ref_dirMichael Haggerty1-5/+7
Instead of keeping a pointer to the `ref_store` in every `ref_dir` entry, store it once in `struct ref_cache`, and change `struct ref_dir` to include a pointer to its containing `ref_cache` instead. This makes it easier to add to the information that is accessible from a `ref_dir` without increasing the size of every `ref_dir` instance. Note that previously, every `ref_dir` pointed at the containing `files_ref_store` regardless of whether it was a part of the loose or packed reference cache. Now we have to be sure to initialize the instances to point at the correct containing `ref_cache`. So change `create_dir_entry()` to take a `ref_cache` parameter, and change its callers to pass the correct `ref_cache` depending on the purpose of the new `dir_entry`. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-16ref-cache: introduce a new type, ref_cacheMichael Haggerty1-1/+15
For now, it just wraps a `ref_entry *` that points at the root of the tree. Soon it will hold more information. Add two new functions, `create_ref_cache()` and `free_ref_cache()`. Make `free_ref_entry()` private. Change files-backend to use this type to hold its caches. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-16refs: split `ref_cache` code into separate filesMichael Haggerty1-0/+512
The `ref_cache` code is currently too tightly coupled to `files-backend`, making the code harder to understand and making it awkward for new code to use `ref_cache` (as we indeed have planned). Start loosening that coupling by splitting `ref_cache` into a separate module. This commit moves code, adds declarations, and changes the visibility of some functions, but doesn't change any code. The modules are still too tightly coupled, but the situation will be improved in subsequent commits. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>