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2016-10-26Merge branch 'jc/cocci-xstrdup-or-null'Libravatar Junio C Hamano1-2/+1
Code cleanup. * jc/cocci-xstrdup-or-null: cocci: refactor common patterns to use xstrdup_or_null()
2016-10-12cocci: refactor common patterns to use xstrdup_or_null()Libravatar Junio C Hamano1-2/+1
d64ea0f83b ("git-compat-util: add xstrdup_or_null helper", 2015-01-12) added a handy wrapper that allows us to get a duplicate of a string or NULL if the original is NULL, but a handful of codepath predate its introduction or just weren't aware of it. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-10Merge branch 'nd/shallow-deepen'Libravatar Junio C Hamano1-1/+7
The existing "git fetch --depth=<n>" option was hard to use correctly when making the history of an existing shallow clone deeper. A new option, "--deepen=<n>", has been added to make this easier to use. "git clone" also learned "--shallow-since=<date>" and "--shallow-exclude=<tag>" options to make it easier to specify "I am interested only in the recent N months worth of history" and "Give me only the history since that version". * nd/shallow-deepen: (27 commits) fetch, upload-pack: --deepen=N extends shallow boundary by N commits upload-pack: add get_reachable_list() upload-pack: split check_unreachable() in two, prep for get_reachable_list() t5500, t5539: tests for shallow depth excluding a ref clone: define shallow clone boundary with --shallow-exclude fetch: define shallow boundary with --shallow-exclude upload-pack: support define shallow boundary by excluding revisions refs: add expand_ref() t5500, t5539: tests for shallow depth since a specific date clone: define shallow clone boundary based on time with --shallow-since fetch: define shallow boundary with --shallow-since upload-pack: add deepen-since to cut shallow repos based on time shallow.c: implement a generic shallow boundary finder based on rev-list fetch-pack: use a separate flag for fetch in deepening mode fetch-pack.c: mark strings for translating fetch-pack: use a common function for verbose printing fetch-pack: use skip_prefix() instead of starts_with() upload-pack: move rev-list code out of check_non_tip() upload-pack: make check_non_tip() clean things up on error upload-pack: tighten number parsing at "deepen" lines ...
2016-09-19Merge branch 'bc/object-id'Libravatar Junio C Hamano1-0/+8
The "unsigned char sha1[20]" to "struct object_id" conversion continues. Notable changes in this round includes that ce->sha1, i.e. the object name recorded in the cache_entry, turns into an object_id. It had merge conflicts with a few topics in flight (Christian's "apply.c split", Dscho's "cat-file --filters" and Jeff Hostetler's "status --porcelain-v2"). Extra sets of eyes double-checking for mismerges are highly appreciated. * bc/object-id: builtin/reset: convert to use struct object_id builtin/commit-tree: convert to struct object_id builtin/am: convert to struct object_id refs: add an update_ref_oid function. sha1_name: convert get_sha1_mb to struct object_id builtin/update-index: convert file to struct object_id notes: convert init_notes to use struct object_id builtin/rm: convert to use struct object_id builtin/blame: convert file to use struct object_id Convert read_mmblob to take struct object_id. notes-merge: convert struct notes_merge_pair to struct object_id builtin/checkout: convert some static functions to struct object_id streaming: make stream_blob_to_fd take struct object_id builtin: convert textconv_object to use struct object_id builtin/cat-file: convert some static functions to struct object_id builtin/cat-file: convert struct expand_data to use struct object_id builtin/log: convert some static functions to use struct object_id builtin/blame: convert struct origin to use struct object_id builtin/apply: convert static functions to struct object_id cache: convert struct cache_entry to use struct object_id
2016-09-19Merge branch 'mh/ref-store'Libravatar Junio C Hamano1-10/+299
The ref-store abstraction was introduced to the refs API so that we can plug in different backends to store references. * mh/ref-store: (38 commits) refs: implement iteration over only per-worktree refs refs: make lock generic refs: add method to rename refs refs: add methods to init refs db refs: make delete_refs() virtual refs: add method for initial ref transaction commit refs: add methods for reflog refs: add method iterator_begin files_ref_iterator_begin(): take a ref_store argument split_symref_update(): add a files_ref_store argument lock_ref_sha1_basic(): add a files_ref_store argument lock_ref_for_update(): add a files_ref_store argument commit_ref_update(): add a files_ref_store argument lock_raw_ref(): add a files_ref_store argument repack_without_refs(): add a files_ref_store argument refs: make peel_ref() virtual refs: make create_symref() virtual refs: make pack_refs() virtual refs: make verify_refname_available() virtual refs: make read_raw_ref() virtual ...
2016-09-09refs: add method to rename refsLibravatar David Turner1-0/+7
This removes the last caller of function get_files_ref_store(), so remove it. Signed-off-by: David Turner <dturner@twopensource.com> Signed-off-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09refs: add methods to init refs dbLibravatar David Turner1-0/+8
Alternate refs backends might not need the refs/heads directory and so on, so we make ref db initialization part of the backend. Signed-off-by: David Turner <dturner@twopensource.com> Signed-off-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09refs: make delete_refs() virtualLibravatar David Turner1-0/+7
In the file-based backend, delete_refs has some special optimization to deal with packed refs. In other backends, we might be able to make ref deletion faster by putting all deletions into a single transaction. So we need a special backend function for this. Signed-off-by: David Turner <dturner@twopensource.com> Signed-off-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09refs: add method for initial ref transaction commitLibravatar David Turner1-0/+8
Signed-off-by: Ronnie Sahlberg <rsahlberg@google.com> Signed-off-by: David Turner <dturner@twopensource.com> Signed-off-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09refs: add methods for reflogLibravatar David Turner1-0/+63
In the file-based backend, the reflog piggybacks on the ref lock. Since other backends won't have the same sort of ref lock, ref backends must also handle reflogs. Signed-off-by: Ronnie Sahlberg <rsahlberg@google.com> Signed-off-by: David Turner <dturner@twopensource.com> Signed-off-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09refs: add method iterator_beginLibravatar Michael Haggerty1-1/+1
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09files_ref_iterator_begin(): take a ref_store argumentLibravatar Michael Haggerty1-1/+1
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09refs: make peel_ref() virtualLibravatar Michael Haggerty1-0/+7
For now it only supports the main reference store. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09refs: make create_symref() virtualLibravatar Michael Haggerty1-0/+9
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09refs: make pack_refs() virtualLibravatar Michael Haggerty1-0/+7
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09refs: make verify_refname_available() virtualLibravatar Michael Haggerty1-0/+10
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09refs: make read_raw_ref() virtualLibravatar Michael Haggerty1-2/+2
Reference backends will be able to customize this function to implement reference reading. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09resolve_gitlink_ref(): rename path parameter to submoduleLibravatar Michael Haggerty1-6/+7
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09resolve_gitlink_ref(): avoid memory allocation in many casesLibravatar Michael Haggerty1-6/+13
If we don't have to strip trailing '/' from the submodule path, then don't allocate and copy the submodule name. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09resolve_gitlink_ref(): implement using resolve_ref_recursively()Libravatar Michael Haggerty1-0/+24
resolve_ref_recursively() can handle references in arbitrary files reference stores, so use it to resolve "gitlink" (i.e., submodule) references. Aside from removing redundant code, this allows submodule lookups to benefit from the much more robust code that we use for reading non-submodule references. And, since the code is now agnostic about reference backends, it will work for any future references backend (so move its definition to refs.c). Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09resolve_ref_recursively(): new functionLibravatar Michael Haggerty1-3/+11
Add a new function, resolve_ref_recursively(), which is basically like the old resolve_ref_unsafe() except that it takes a (ref_store *) argument and also works for submodules. Re-implement resolve_ref_unsafe() as a thin wrapper around resolve_ref_recursively(). Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09read_raw_ref(): take a (struct ref_store *) argumentLibravatar Michael Haggerty1-1/+3
And make the function work for submodules. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09refs: add a transaction_commit() methodLibravatar Ronnie Sahlberg1-0/+9
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com> Signed-off-by: David Turner <dturner@twopensource.com> Signed-off-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09refs: create a base class "ref_store" for files_ref_storeLibravatar Michael Haggerty1-0/+93
We want ref_stores to be polymorphic, so invent a base class of which files_ref_store is a derived class. For now there is exactly one ref_store for the main repository and one for any submodules whose references have been accessed. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09refs: add a backend method structureLibravatar Ronnie Sahlberg1-0/+19
Add a `struct ref_storage_be` to represent types of reference stores. In OO notation, this is the class, and will soon hold some class methods (e.g., a factory to create new ref_store instances) and will also serve as the vtable for ref_store instances of that type. As yet, the backends cannot do anything. Signed-off-by: Ronnie Sahlberg <sahlberg@google.com> Signed-off-by: David Turner <dturner@twopensource.com> Signed-off-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-09rename_ref_available(): add docstringLibravatar David Turner1-6/+6
And improve the internal variable names. Signed-off-by: David Turner <dturner@twopensource.com> Signed-off-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-07refs: add an update_ref_oid function.Libravatar brian m. carlson1-0/+8
Several places around the codebase want to pass update_ref data from struct object_id, but update_ref may also be passed NULL pointers. Instead of checking and dereferencing in every caller, create an update_ref_oid which wraps update_ref and provides this functionality. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-08-01pass constants as first argument to st_mult()Libravatar René Scharfe1-1/+1
The result of st_mult() is the same no matter the order of its arguments. It invokes the macro unsigned_mult_overflows(), which divides the second parameter by the first one. Pass constants first to allow that division to be done already at compile time. Signed-off-by: Rene Scharfe <l.s.r@web.de> Reviewed-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-20do_for_each_ref(): reimplement using reference iterationLibravatar Michael Haggerty1-0/+20
Use the reference iterator interface to implement do_for_each_ref(). Delete a bunch of code supporting the old for_each_ref() implementation. And now that do_for_each_ref() is generic code (it is no longer tied to the files backend), move it to refs.c. The implementation is via a new function, do_for_each_ref_iterator(), which takes a reference iterator as argument and calls a callback function for each of the references in the iterator. This change requires the current_ref performance hack for peel_ref() to be implemented via ref_iterator_peel() rather than peel_entry() because we don't have a ref_entry handy (it is hidden under three layers: file_ref_iterator, merge_ref_iterator, and cache_ref_iterator). So: * do_for_each_ref_iterator() records the active iterator in current_ref_iter while it is running. * peel_ref() checks whether current_ref_iter is pointing at the requested reference. If so, it asks the iterator to peel the reference (which it can do efficiently via its "peel" virtual function). For extra safety, we do the optimization only if the refname *addresses* are the same, not only if the refname *strings* are the same, to forestall possible mixups between refnames that come from different ref_iterators. Please note that this optimization of peel_ref() is only available when iterating via do_for_each_ref_iterator() (including all of the for_each_ref() functions, which call it indirectly). It would be complicated to implement a similar optimization when iterating directly using a reference iterator, because multiple reference iterators can be in use at the same time, with interleaved calls to ref_iterator_advance(). (In fact we do exactly that in merge_ref_iterator.) But that is not necessary. peel_ref() is only called while iterating over references. Callers who iterate using the for_each_ref() functions benefit from the optimization described above. Callers who iterate using reference iterators directly have access to the ref_iterator, so they can call ref_iterator_peel() themselves to get an analogous optimization in a more straightforward manner. If we rewrite all callers to use the reference iteration API, then we can remove the current_ref_iter hack permanently. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-13refs: add expand_ref()Libravatar Nguyễn Thái Ngọc Duy1-1/+7
This is basically dwim_ref() without @{} support. To be used on the server side where we want to expand abbreviated to full ref names and nothing else. The first user is "git clone/fetch --shallow-exclude". Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-13ref_transaction_update(): check refname_is_safe() at a minimumLibravatar Michael Haggerty1-2/+3
If the user has asked that a new value be set for a reference, we use check_refname_format() to verify that the reference name satisfies all of the rules. But in other cases, at least check that refname_is_safe(). Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
2016-06-13add_update(): initialize the whole ref_updateLibravatar Michael Haggerty1-22/+26
Change add_update() to initialize all of the fields in the new ref_update object. Rename the function to ref_transaction_add_update(), and increase its visibility to all of the refs-related code. All of this makes the function more useful for other future callers. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
2016-06-13ref_transaction_create(): disallow recursive pruningLibravatar Michael Haggerty1-0/+3
It is nonsensical (and a little bit dangerous) to use REF_ISPRUNING without REF_NODEREF. Forbid it explicitly. Change the one REF_ISPRUNING caller to pass REF_NODEREF too. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
2016-06-13refs: make error messages more consistentLibravatar Michael Haggerty1-4/+4
* Always start error messages with a lower-case letter. * Always enclose reference names in single quotes. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
2016-05-05refname_is_safe(): insist that the refname already be normalizedLibravatar Michael Haggerty1-2/+7
The reference name is going to be compared to other reference names, so it should be in its normalized form. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
2016-05-05refname_is_safe(): don't allow the empty stringLibravatar Michael Haggerty1-2/+3
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
2016-05-05refname_is_safe(): use skip_prefix()Libravatar Michael Haggerty1-3/+5
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
2016-04-10refs: move resolve_ref_unsafe into common codeLibravatar David Turner1-0/+74
Now that resolve_ref_unsafe's only interaction with the backend is through read_raw_ref, we can move it into the common code. Later, we'll replace read_raw_ref with a backend function. Signed-off-by: David Turner <dturner@twopensource.com> Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-04-10refs: move for_each_*ref* functions into common codeLibravatar David Turner1-0/+52
Make do_for_each_ref take a submodule as an argument instead of a ref_cache. Since all for_each_*ref* functions are defined in terms of do_for_each_ref, we can then move them into the common code. Later, we can simply make do_for_each_ref into a backend function. Signed-off-by: David Turner <dturner@twopensource.com> Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-04-10refs: move head_ref{,_submodule} to the common codeLibravatar David Turner1-0/+23
These don't use any backend-specific functions. These were previously defined in terms of the do_head_ref helper function, but since they are otherwise identical, we don't need that function. Signed-off-by: David Turner <dturner@twopensource.com> Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22use st_add and st_mult for allocation size computationLibravatar Jeff King1-1/+1
If our size computation overflows size_t, we may allocate a much smaller buffer than we expected and overflow it. It's probably impossible to trigger an overflow in most of these sites in practice, but it is easy enough convert their additions and multiplications into overflow-checking variants. This may be fixing real bugs, and it makes auditing the code easier. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22convert trivial cases to FLEX_ARRAY macrosLibravatar Jeff King1-4/+2
Using FLEX_ARRAY macros reduces the amount of manual computation size we have to do. It also ensures we don't overflow size_t, and it makes sure we write the same number of bytes that we allocated. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22use xmallocz to avoid size arithmeticLibravatar Jeff King1-1/+1
We frequently allocate strings as xmalloc(len + 1), where the extra 1 is for the NUL terminator. This can be done more simply with xmallocz, which also checks for integer overflow. There's no case where switching xmalloc(n+1) to xmallocz(n) is wrong; the result is the same length, and malloc made no guarantees about what was in the buffer anyway. But in some cases, we can stop manually placing NUL at the end of the allocated buffer. But that's only safe if it's clear that the contents will always fill the buffer. In each case where this patch does so, I manually examined the control flow, and I tried to err on the side of caution. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-12-10Merge branch 'bc/object-id'Libravatar Junio C Hamano1-1/+1
More transition from "unsigned char[40]" to "struct object_id". This needed a few merge fixups, but is mostly disentangled from other topics. * bc/object-id: remote: convert functions to struct object_id Remove get_object_hash. Convert struct object to object_id Add several uses of get_object_hash. object: introduce get_object_hash macro. ref_newer: convert to use struct object_id push_refs_with_export: convert to struct object_id get_remote_heads: convert to struct object_id parse_fetch: convert to use struct object_id add_sought_entry_mem: convert to struct object_id Convert struct ref to use object_id. sha1_file: introduce has_object_file helper.
2015-12-08Merge branch 'dt/refs-backend-pre-vtable'Libravatar Junio C Hamano1-3669/+42
Code preparation for pluggable ref backends. * dt/refs-backend-pre-vtable: refs: break out ref conflict checks files_log_ref_write: new function initdb: make safe_create_dir public refs: split filesystem-based refs code into a new file refs/refs-internal.h: new header file refname_is_safe(): improve docstring pack_if_possible_fn(): use ref_type() instead of is_per_worktree_ref() copy_msg(): rename to copy_reflog_msg() verify_refname_available(): new function verify_refname_available(): rename function
2015-11-20Remove get_object_hash.Libravatar brian m. carlson1-1/+1
Convert all instances of get_object_hash to use an appropriate reference to the hash member of the oid member of struct object. This provides no functional change, as it is essentially a macro substitution. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Jeff King <peff@peff.net>
2015-11-20Add several uses of get_object_hash.Libravatar brian m. carlson1-1/+1
Convert most instances where the sha1 member of struct object is dereferenced to use get_object_hash. Most instances that are passed to functions that have versions taking struct object_id, such as get_sha1_hex/get_oid_hex, or instances that can be trivially converted to use struct object_id instead, are not converted. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Jeff King <peff@peff.net>
2015-11-20refs: break out ref conflict checksLibravatar David Turner1-0/+44
Create new function find_descendant_ref, to hold one of the ref conflict checks used in verify_refname_available. Multiple backends will need this function, so move it to the common code. Also move rename_ref_available to the common code, because alternate backends might need it and it has no files-backend-specific code. Signed-off-by: David Turner <dturner@twopensource.com> Signed-off-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Jeff King <peff@peff.net>
2015-11-20refs: split filesystem-based refs code into a new fileLibravatar Michael Haggerty1-3535/+4
As another step in the move to pluggable reference backends, move the code that is specific to the filesystem-based reference backend (i.e., the current system of storing references as loose and packed files) into a separate file, refs/files-backend.c. Aside from a tiny bit of file header boilerplate, this commit only moves a subset of the code verbatim from refs.c to the new file, as can easily be verified using patience diff: git diff --patience $commit^:refs.c $commit:refs.c git diff --patience $commit^:refs.c $commit:refs/files-backend.c Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Jeff King <peff@peff.net>
2015-11-20refs/refs-internal.h: new header fileLibravatar Michael Haggerty1-165/+9
There are a number of constants, structs, and static functions defined in refs.c and treated as private to the references module. But we want to support multiple reference backends within the reference module, and those backends will need access to some heretofore private declarations. We don't want those declarations to be visible to non-refs code, so we don't want to move them to refs.h. Instead, add a new header file, refs/refs-internal.h, that is intended to be included only from within the refs module. Make some functions non-static and move some declarations (and their corresponding docstrings) from refs.c to this file. In a moment we will add more content to the "refs" subdirectory. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Jeff King <peff@peff.net>