While this field most of the time contains the canonical object size,
there is one case it does not: when we have found that the base object
of the delta in question is also to be packed, we will very happily
reuse the delta by copying it over instead of regenerating the new
delta.
"size" in this case will record the delta size, not canonical object
size. Later on in write_reuse_object(), we reconstruct the delta
header and "size" is used for this purpose. When this happens, the
"type" field contains a delta type instead of a canonical type.
Highlight this in the code since it could be tricky to see.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
sha1_object_info() in check_objects() may fail to locate an object in
the pack and return type OBJ_BAD. In that case, it will likely leave
the "size" field untouched. We delay error handling until later in
prepare_pack() though. Until then, do not touch "size" field.
This field should contain the default value zero, but we can't say
sha1_object_info() cannot damage it. This becomes more important later
when the object size may have to be retrieved back from the
(non-existing) pack.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We only cache deltas when it's smaller than a certain limit. This limit
defaults to 1000 but save its compressed length in a 64-bit field.
Shrink that field down to 20 bits, so you can only cache 1MB deltas.
Larger deltas must be recomputed at when the pack is written down.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These delta pointers always point to elements in the objects[] array
in packing_data struct. We can only hold maximum 4G of those objects
because the array size in nr_objects is uint32_t. We could use
uint32_t indexes to address these elements instead of pointers. On
64-bit architecture (8 bytes per pointer) this would save 4 bytes per
pointer.
Convert these delta pointers to indexes. Since we need to handle NULL
pointers as well, the index is shifted by one [1].
[1] This means we can only index 2^32-2 objects even though nr_objects
could contain 2^32-1 objects. It should not be a problem in
practice because when we grow objects[], nr_alloc would probably
blow up long before nr_objects hits the wall.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of using 8 bytes (on 64 bit arch) to store a pointer to a
pack. Use an index instead since the number of packs should be
relatively small.
This limits the number of packs we can handle to 1k. Since we can't be
sure people can never run into the situation where they have more than
1k pack files. Provide a fall back route for it.
If we find out they have too many packs, the new in_pack_by_idx[]
array (which has at most 1k elements) will not be used. Instead we
allocate in_pack[] array that holds nr_objects elements. This is
similar to how the optional in_pack_pos field is handled.
The new simple test is just to make sure the too-many-packs code path
is at least executed. The true test is running
make test GIT_TEST_FULL_IN_PACK_ARRAY=1
to take advantage of other special case tests.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This field is only need for pack-bitmap, which is an optional
feature. Move it to a separate array that is only allocated when
pack-bitmap is used (like objects[], it is not freed, since we need it
until the end of the process)
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Because of struct packing from now on we can only handle max depth
4095 (or even lower when new booleans are added in this struct). This
should be ok since long delta chain will cause significant slow down
anyway.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
An extra field type_valid is added to carry the equivalent of OBJ_BAD
in the original "type" field. in_pack_type always contains a valid
type so we only need 3 bits for it.
A note about accepting OBJ_NONE as "valid" type. The function
read_object_list_from_stdin() can pass this value [1] and it
eventually calls create_object_entry() where current code skip setting
"type" field if the incoming type is zero. This does not have any bad
side effects because "type" field should be memset()'d anyway.
But since we also need to set type_valid now, skipping oe_set_type()
leaves type_valid zero/false, which will make oe_type() return
OBJ_BAD, not OBJ_NONE anymore. Apparently we do care about OBJ_NONE in
prepare_pack(). This switch from OBJ_NONE to OBJ_BAD may trigger
fatal: unable to get type of object ...
Accepting OBJ_NONE [2] does sound wrong, but this is how it is has
been for a very long time and I haven't time to dig in further.
[1] See 5c49c11686 (pack-objects: better check_object() performances -
2007-04-16)
[2] 21666f1aae (convert object type handling from a string to a number
- 2007-02-26)
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Refactoring the internal global data structure to make it possible
to open multiple repositories, work with and then close them.
Rerolled by Duy on top of a separate preliminary clean-up topic.
The resulting structure of the topics looked very sensible.
* sb/object-store: (27 commits)
sha1_file: allow sha1_loose_object_info to handle arbitrary repositories
sha1_file: allow map_sha1_file to handle arbitrary repositories
sha1_file: allow map_sha1_file_1 to handle arbitrary repositories
sha1_file: allow open_sha1_file to handle arbitrary repositories
sha1_file: allow stat_sha1_file to handle arbitrary repositories
sha1_file: allow sha1_file_name to handle arbitrary repositories
sha1_file: add repository argument to sha1_loose_object_info
sha1_file: add repository argument to map_sha1_file
sha1_file: add repository argument to map_sha1_file_1
sha1_file: add repository argument to open_sha1_file
sha1_file: add repository argument to stat_sha1_file
sha1_file: add repository argument to sha1_file_name
sha1_file: allow prepare_alt_odb to handle arbitrary repositories
sha1_file: allow link_alt_odb_entries to handle arbitrary repositories
sha1_file: add repository argument to prepare_alt_odb
sha1_file: add repository argument to link_alt_odb_entries
sha1_file: add repository argument to read_info_alternates
sha1_file: add repository argument to link_alt_odb_entry
sha1_file: add raw_object_store argument to alt_odb_usable
pack: move approximate object count to object store
...
Conversion from uchar[20] to struct object_id continues.
* bc/object-id: (36 commits)
convert: convert to struct object_id
sha1_file: introduce a constant for max header length
Convert lookup_replace_object to struct object_id
sha1_file: convert read_sha1_file to struct object_id
sha1_file: convert read_object_with_reference to object_id
tree-walk: convert tree entry functions to object_id
streaming: convert istream internals to struct object_id
tree-walk: convert get_tree_entry_follow_symlinks internals to object_id
builtin/notes: convert static functions to object_id
builtin/fmt-merge-msg: convert remaining code to object_id
sha1_file: convert sha1_object_info* to object_id
Convert remaining callers of sha1_object_info_extended to object_id
packfile: convert unpack_entry to struct object_id
sha1_file: convert retry_bad_packed_offset to struct object_id
sha1_file: convert assert_sha1_type to object_id
builtin/mktree: convert to struct object_id
streaming: convert open_istream to use struct object_id
sha1_file: convert check_sha1_signature to struct object_id
sha1_file: convert read_loose_object to use struct object_id
builtin/index-pack: convert struct ref_delta_entry to object_id
...
The reason callers have to call this is to make sure either packed_git
or packed_git_mru pointers are initialized since we don't do that by
default. Sometimes it's hard to see this connection between where the
function is called and where packed_git pointer is used (sometimes in
separate functions).
Keep this dependency internal because now all access to packed_git and
packed_git_mru must go through get_xxx() wrappers.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a repository argument to allow prepare_packed_git callers to be
more specific about which repository to handle. See commit "sha1_file:
add repository argument to link_alt_odb_entry" for an explanation of
the #define trick.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a process with multiple repositories open, packfile accessors
should be associated to a single repository and not shared globally.
Move packed_git and packed_git_mru into the_repository and adjust
callers to reflect this.
[nd: while at there, wrap access to these two fields in get_packed_git()
and get_packed_git_mru(). This allows us to lazily initialize these
fields without caller doing that explicitly]
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert read_sha1_file to take a pointer to struct object_id and rename
it read_object_file. Do the same for read_sha1_file_extended.
Convert one use in grep.c to use the new function without any other code
change, since the pointer being passed is a void pointer that is already
initialized with a pointer to struct object_id. Update the declaration
and definitions of the modified functions, and apply the following
semantic patch to convert the remaining callers:
@@
expression E1, E2, E3;
@@
- read_sha1_file(E1.hash, E2, E3)
+ read_object_file(&E1, E2, E3)
@@
expression E1, E2, E3;
@@
- read_sha1_file(E1->hash, E2, E3)
+ read_object_file(E1, E2, E3)
@@
expression E1, E2, E3, E4;
@@
- read_sha1_file_extended(E1.hash, E2, E3, E4)
+ read_object_file_extended(&E1, E2, E3, E4)
@@
expression E1, E2, E3, E4;
@@
- read_sha1_file_extended(E1->hash, E2, E3, E4)
+ read_object_file_extended(E1, E2, E3, E4)
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert read_object_with_reference to take pointers to struct object_id.
Update the internals of the function accordingly.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert sha1_object_info and sha1_object_info_extended to take pointers
to struct object_id and rename them to use "oid" instead of "sha1" in
their names. Update the declaration and definition and apply the
following semantic patch, plus the standard object_id transforms:
@@
expression E1, E2;
@@
- sha1_object_info(E1.hash, E2)
+ oid_object_info(&E1, E2)
@@
expression E1, E2;
@@
- sha1_object_info(E1->hash, E2)
+ oid_object_info(E1, E2)
@@
expression E1, E2, E3;
@@
- sha1_object_info_extended(E1.hash, E2, E3)
+ oid_object_info_extended(&E1, E2, E3)
@@
expression E1, E2, E3;
@@
- sha1_object_info_extended(E1->hash, E2, E3)
+ oid_object_info_extended(E1, E2, E3)
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since the "flags" is shared, it's a good idea to keep track of who
uses what bit. When we need to use more flags in library code, we can
be sure it won't be re-used for another purpose by some caller.
While at there, fix the location of "5" (should be in a different
column than "4" two lines down)
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
More abstraction of hash function from the codepath.
* bc/hash-algo:
hash: update obsolete reference to SHA1_HEADER
bulk-checkin: abstract SHA-1 usage
csum-file: abstract uses of SHA-1
csum-file: rename sha1file to hashfile
read-cache: abstract away uses of SHA-1
pack-write: switch various SHA-1 values to abstract forms
pack-check: convert various uses of SHA-1 to abstract forms
fast-import: switch various uses of SHA-1 to the_hash_algo
sha1_file: switch uses of SHA-1 to the_hash_algo
builtin/unpack-objects: switch uses of SHA-1 to the_hash_algo
builtin/index-pack: improve hash function abstraction
hash: create union for hash context allocation
hash: move SHA-1 macros to hash.h
Rename C++ keyword in order to bring the codebase closer to being able
to be compiled with a C++ compiler.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Retire mru API as it does not give enough abstraction over
underlying list API to be worth it.
* gs/retire-mru:
mru: Replace mru.[ch] with list.h implementation
The first step to getting rid of mru API and using the
doubly-linked list API directly instead.
* ot/mru-on-list:
mru: use double-linked list from list.h
In preparation for implementing narrow/partial clone, the machinery
for checking object connectivity used by gc and fsck has been
taught that a missing object is OK when it is referenced by a
packfile specially marked as coming from trusted repository that
promises to make them available on-demand and lazily.
* jh/fsck-promisors:
gc: do not repack promisor packfiles
rev-list: support termination at promisor objects
sha1_file: support lazily fetching missing objects
introduce fetch-object: fetch one promisor object
index-pack: refactor writing of .keep files
fsck: support promisor objects as CLI argument
fsck: support referenced promisor objects
fsck: support refs pointing to promisor objects
fsck: introduce partialclone extension
extension.partialclone: introduce partial clone extension
Rename struct sha1file to struct hashfile, along with all of its related
functions.
The transformation in this commit was made by global search-and-replace.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert the definition and declaration of force_object_loose to
struct object_id and adjust usage of this function.
Signed-off-by: Patryk Obara <patryk.obara@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Replace the custom calls to mru.[ch] with calls to list.h. This patch is
the final step in removing the mru API completely and inlining the logic.
This patch leads to significant code reduction and the mru API hence, is
not a useful abstraction anymore.
Signed-off-by: Gargi Sharma <gs051095@gmail.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In preparation for implementing narrow/partial clone, the object
walking machinery has been taught a way to tell it to "filter" some
objects from enumeration.
* jh/object-filtering:
rev-list: support --no-filter argument
list-objects-filter-options: support --no-filter
list-objects-filter-options: fix 'keword' typo in comment
pack-objects: add list-objects filtering
rev-list: add list-objects filtering support
list-objects: filter objects in traverse_commit_list
oidset: add iterator methods to oidset
oidmap: add oidmap iterator methods
dir: allow exclusions from blob in addition to file
Teach gc to stop traversal at promisor objects, and to leave promisor
packfiles alone. This has the effect of only repacking non-promisor
packfiles, and preserves the distinction between promisor packfiles and
non-promisor packfiles.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach pack-objects to use the filtering provided by the
traverse_commit_list_filtered() interface to omit unwanted
objects from the resulting packfile.
Filtering requires the use of the "--stdout" option.
Add t5317 test.
In the future, we will introduce a "partial clone" mechanism
wherein an object in a repo, obtained from a remote, may
reference a missing object that can be dynamically fetched from
that remote once needed. This "partial clone" mechanism will
have a way, sometimes slow, of determining if a missing link
is one of the links expected to be produced by this mechanism.
This patch introduces handling of missing objects to help
debugging and development of the "partial clone" mechanism,
and once the mechanism is implemented, for a power user to
perform operations that are missing-object aware without
incurring the cost of checking if a missing link is expected.
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert peel_ref (and its corresponding backend) to struct object_id.
This transformation was done with an update to the declaration,
definition, comments, and test helper and the following semantic patch:
@@
expression E1, E2;
@@
- peel_ref(E1, E2.hash)
+ peel_ref(E1, &E2)
@@
expression E1, E2;
@@
- peel_ref(E1, E2->hash)
+ peel_ref(E1, E2)
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is one of the last unconverted callers to peel_ref. While we're
fixing that, convert the rest of the file, since it will need to be
converted at some point anyway.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert traverse_bitmap_commit_list and the callbacks it takes to use a
pointer to struct object_id.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A common mistake when writing binary search is to allow possible
integer overflow by using the simple average:
mid = (min + max) / 2;
Instead, use the overflow-safe version:
mid = min + (max - min) / 2;
This translation is safe since the operation occurs inside a loop
conditioned on "min < max". The included changes were found using
the following git grep:
git grep '/ *2;' '*.c'
Making this cleanup will prevent future review friction when a new
binary search is contructed based on existing code.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Simplify mru.[ch] and related code by reusing the double-linked list
implementation from list.h instead of a custom one.
This commit is an intermediate step. Our final goal is to get rid of
mru.[ch] at all and inline all logic.
Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored by: Jeff King <peff@peff.net>
Signed-off-by: Olga Telezhnaia <olyatelezhnaya@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The MRU cache that keeps track of recently used packs is represented
using two global variables:
struct mru packed_git_mru_storage;
struct mru *packed_git_mru = &packed_git_mru_storage;
Callers never assign to the packed_git_mru pointer, though, so we can
simplify by eliminating it and using &packed_git_mru_storage (renamed
to &packed_git_mru) directly. This variable is only used by the
packfile subsystem, making this a relatively uninvasive change (and
any new unadapted callers would trigger a compile error).
Noticed while moving these globals to the object_store struct.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
alloc_packed_git() in packfile.c is duplicated from sha1_file.c. In a
subsequent commit, alloc_packed_git() will be removed from sha1_file.c.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When checking the conditional of "while (me->remaining)", we did not
hold the lock. Calling find_deltas would still be safe, since it checks
"remaining" (after taking the lock) and is able to handle all values. In
fact, this could (currently) not trigger any bug: a bug could happen if
`remaining` transitioning from zero to non-zero races with the evaluation
of the while-condition, but these are always separated by the
data_ready-mechanism.
Make sure we have the lock when we read `remaining`. This does mean we
release it just so that find_deltas can take it immediately again. We
could tweak the contract so that the lock should be taken before calling
find_deltas, but let's defer that until someone can actually show that
"unlock+lock" has a measurable negative impact.
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If done_pbase_paths is NULL then done_pbase_paths_num must be zero and
done_pbase_path_pos() returns -1 without accessing the array, so the
check is not necessary.
If the invariant was violated then the check would make sure we keep
on going and allocate the necessary amount of memory in the next
ALLOC_GROW call. That sounds nice, but all array entries except for
one would contain garbage data.
If the invariant was violated without the check we'd get a segfault in
done_pbase_path_pos(), i.e. an observable crash, alerting us of the
presence of a bug.
Currently there is no such bug: Only the functions check_pbase_path()
and cleanup_preferred_base() change pointer and counter, and both make
sure to keep them in sync. Get rid of the check anyway to allow us to
see if later changes introduce such a defect, and to simplify the code.
Detected by Coverity Scan.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Simplify the code for moving members inside of an array and make it more
robust by using the helper macro MOVE_ARRAY. It calculates the size
based on the specified number of elements for us and supports NULL
pointers when that number is zero. Raw memmove(3) calls with NULL can
cause the compiler to (over-eagerly) optimize out later NULL checks.
This patch was generated with contrib/coccinelle/array.cocci and spatch
(Coccinelle).
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A common pattern to free a piece of memory and assign NULL to the
pointer that used to point at it has been replaced with a new
FREE_AND_NULL() macro.
* ab/free-and-null:
*.[ch] refactoring: make use of the FREE_AND_NULL() macro
coccinelle: make use of the "expression" FREE_AND_NULL() rule
coccinelle: add a rule to make "expression" code use FREE_AND_NULL()
coccinelle: make use of the "type" FREE_AND_NULL() rule
coccinelle: add a rule to make "type" code use FREE_AND_NULL()
git-compat-util: add a FREE_AND_NULL() wrapper around free(ptr); ptr = NULL
