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92 Commits

Author SHA1 Message Date
Stefan Beller 108ed1a3d8 object.c: allow parse_object_buffer to handle arbitrary repositories
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-29 10:43:40 -07:00
Stefan Beller 65ea9d4bec commit.c: migrate the commit buffer to the parsed object store
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-29 10:43:40 -07:00
Stefan Beller 94c09a7197 object: allow lookup_object to handle arbitrary repositories
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-29 10:43:39 -07:00
Stefan Beller a962da1ef5 object: allow object_as_type to handle arbitrary repositories
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-29 10:43:39 -07:00
Stefan Beller 1268dfac1e object: add repository argument to object_as_type
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-29 10:43:38 -07:00
Stefan Beller 1ec5bfd24e object: add repository argument to parse_object_buffer
Add a repository argument to allow the callers of parse_object_buffer
to be more specific about which repository to act on. This is a small
mechanical change; it doesn't change the implementation to handle
repositories other than the_repository yet.

As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-29 10:43:38 -07:00
Stefan Beller 5abddd1eb7 object: add repository argument to lookup_object
Add a repository argument to allow callers of lookup_object to be more
specific about which repository to handle. This is a small mechanical
change; it doesn't change the implementation to handle repositories
other than the_repository yet.

As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-29 10:43:38 -07:00
Stefan Beller 109cd76dd3 object: add repository argument to parse_object
Add a repository argument to allow the callers of parse_object
to be more specific about which repository to act on. This is a small
mechanical change; it doesn't change the implementation to handle
repositories other than the_repository yet.

As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-29 10:43:38 -07:00
Junio C Hamano b16b60f71b Merge branch 'sb/object-store-grafts' into sb/object-store-lookup
* sb/object-store-grafts:
  commit: allow lookup_commit_graft to handle arbitrary repositories
  commit: allow prepare_commit_graft to handle arbitrary repositories
  shallow: migrate shallow information into the object parser
  path.c: migrate global git_path_* to take a repository argument
  cache: convert get_graft_file to handle arbitrary repositories
  commit: convert read_graft_file to handle arbitrary repositories
  commit: convert register_commit_graft to handle arbitrary repositories
  commit: convert commit_graft_pos() to handle arbitrary repositories
  shallow: add repository argument to is_repository_shallow
  shallow: add repository argument to check_shallow_file_for_update
  shallow: add repository argument to register_shallow
  shallow: add repository argument to set_alternate_shallow_file
  commit: add repository argument to lookup_commit_graft
  commit: add repository argument to prepare_commit_graft
  commit: add repository argument to read_graft_file
  commit: add repository argument to register_commit_graft
  commit: add repository argument to commit_graft_pos
  object: move grafts to object parser
  object-store: move object access functions to object-store.h
2018-06-29 10:43:28 -07:00
Junio C Hamano 110240588d Merge branch 'sb/object-store-alloc'
The conversion to pass "the_repository" and then "a_repository"
throughout the object access API continues.

* sb/object-store-alloc:
  alloc: allow arbitrary repositories for alloc functions
  object: allow create_object to handle arbitrary repositories
  object: allow grow_object_hash to handle arbitrary repositories
  alloc: add repository argument to alloc_commit_index
  alloc: add repository argument to alloc_report
  alloc: add repository argument to alloc_object_node
  alloc: add repository argument to alloc_tag_node
  alloc: add repository argument to alloc_commit_node
  alloc: add repository argument to alloc_tree_node
  alloc: add repository argument to alloc_blob_node
  object: add repository argument to grow_object_hash
  object: add repository argument to create_object
  repository: introduce parsed objects field
2018-06-25 13:22:38 -07:00
Junio C Hamano b3b2aaf0fd Merge branch 'nd/commit-util-to-slab'
The in-core "commit" object had an all-purpose "void *util" field,
which was tricky to use especially in library-ish part of the
code.  All of the existing uses of the field has been migrated to a
more dedicated "commit-slab" mechanism and the field is eliminated.

* nd/commit-util-to-slab:
  commit.h: delete 'util' field in struct commit
  merge: use commit-slab in merge remote desc instead of commit->util
  log: use commit-slab in prepare_bases() instead of commit->util
  show-branch: note about its object flags usage
  show-branch: use commit-slab for commit-name instead of commit->util
  name-rev: use commit-slab for rev-name instead of commit->util
  bisect.c: use commit-slab for commit weight instead of commit->util
  revision.c: use commit-slab for show_source
  sequencer.c: use commit-slab to associate todo items to commits
  sequencer.c: use commit-slab to mark seen commits
  shallow.c: use commit-slab for commit depth instead of commit->util
  describe: use commit-slab for commit names instead of commit->util
  blame: use commit-slab for blame suspects instead of commit->util
  commit-slab: support shared commit-slab
  commit-slab.h: code split
2018-06-25 13:22:35 -07:00
Junio C Hamano ad635e82d6 Merge branch 'nd/pack-objects-pack-struct'
"git pack-objects" needs to allocate tons of "struct object_entry"
while doing its work, and shrinking its size helps the performance
quite a bit.

* nd/pack-objects-pack-struct:
  ci: exercise the whole test suite with uncommon code in pack-objects
  pack-objects: reorder members to shrink struct object_entry
  pack-objects: shrink delta_size field in struct object_entry
  pack-objects: shrink size field in struct object_entry
  pack-objects: clarify the use of object_entry::size
  pack-objects: don't check size when the object is bad
  pack-objects: shrink z_delta_size field in struct object_entry
  pack-objects: refer to delta objects by index instead of pointer
  pack-objects: move in_pack out of struct object_entry
  pack-objects: move in_pack_pos out of struct object_entry
  pack-objects: use bitfield for object_entry::depth
  pack-objects: use bitfield for object_entry::dfs_state
  pack-objects: turn type and in_pack_type to bitfields
  pack-objects: a bit of document about struct object_entry
  read-cache.c: make $GIT_TEST_SPLIT_INDEX boolean
2018-05-23 14:38:19 +09:00
Nguyễn Thái Ngọc Duy 44cecbf8a0 show-branch: note about its object flags usage
This is another candidate for commit-slab. Keep Junio's observation in
code so we can search it later on when somebody wants to improve the
code.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-21 14:07:20 +09:00
Stefan Beller 2f6c767fd4 commit: allow prepare_commit_graft to handle arbitrary repositories
Move the global variable 'commit_graft_prepared' into the object
pool and convert the function prepare_commit_graft to work
an arbitrary repositories.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-18 08:13:10 +09:00
Stefan Beller eee4502baa shallow: migrate shallow information into the object parser
We need to convert the shallow functions all at the same time
as we move the data structures they operate on into the repository.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-18 08:13:10 +09:00
Jonathan Nieder 6a1a79fd14 object: move grafts to object parser
Grafts are only meaningful in the context of a single repository.
Therefore they cannot be global.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-16 11:42:03 +09:00
Stefan Beller 14ba97f81c alloc: allow arbitrary repositories for alloc functions
We have to convert all of the alloc functions at once, because alloc_report
uses a funky macro for reporting. It is better for the sake of mechanical
conversion to convert multiple functions at once rather than changing the
structure of the reporting function.

We record all memory allocation in alloc.c, and free them in
clear_alloc_state, which is called for all repositories except
the_repository.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-16 11:16:50 +09:00
Stefan Beller 341e45e46b object: allow create_object to handle arbitrary repositories
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-09 12:12:37 +09:00
Stefan Beller 68f95d382b object: add repository argument to create_object
Add a repository argument to allow the callers of create_object
to be more specific about which repository to act on. This is a small
mechanical change; it doesn't change the implementation to handle
repositories other than the_repository yet.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-09 12:12:36 +09:00
Stefan Beller 99bf115c87 repository: introduce parsed objects field
Convert the existing global cache for parsed objects (obj_hash) into
repository-specific parsed object caches. Existing code that uses
obj_hash are modified to use the parsed object cache of
the_repository; future patches will use the parsed object caches of
other repositories.

Another future use case for a pool of objects is ease of memory management
in revision walking: If we can free the rev-list related memory early in
pack-objects (e.g. part of repack operation) then it could lower memory
pressure significantly when running on large repos. While this has been
discussed on the mailing list lately, this series doesn't implement this.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-09 12:12:36 +09:00
Nguyễn Thái Ngọc Duy fd9b1baef8 pack-objects: turn type and in_pack_type to bitfields
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>
2018-04-16 12:38:58 +09:00
Stefan Beller e5e5e08832 sha1_name.c: rename to use dash in file name
This is more consistent with the project style. The majority of Git's
source files use dashes in preference to underscores in their file names.

Signed-off-by: Stefan Beller <sbeller@google.com>
2018-04-11 18:11:00 +09:00
Junio C Hamano 99321e327b Merge branch 'nd/object-allocation-comments'
Code doc update.

* nd/object-allocation-comments:
  object.h: realign object flag allocation comment
  object.h: update flag allocation comment
2018-03-14 12:01:06 -07:00
Nguyễn Thái Ngọc Duy 3d1cf1e8e1 object.h: realign object flag allocation comment
Some new path names are too long and eat into the graph part. Move the
graph 9 columns to the right to avoid this.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-03-06 11:41:22 -08:00
Nguyễn Thái Ngọc Duy 95308d64ce object.h: update flag allocation comment
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>
2018-03-06 11:41:21 -08:00
Junio C Hamano e17cec27d1 Merge branch 'rs/lose-leak-pending' into maint
API clean-up around revision traversal.

* rs/lose-leak-pending:
  commit: remove unused function clear_commit_marks_for_object_array()
  revision: remove the unused flag leak_pending
  checkout: avoid using the rev_info flag leak_pending
  bundle: avoid using the rev_info flag leak_pending
  bisect: avoid using the rev_info flag leak_pending
  object: add clear_commit_marks_all()
  ref-filter: use clear_commit_marks_many() in do_merge_filter()
  commit: use clear_commit_marks_many() in remove_redundant()
  commit: avoid allocation in clear_commit_marks_many()
2018-02-15 15:18:11 -08:00
Brandon Williams debca9d2fe object: rename function 'typename' to 'type_name'
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>
2018-02-14 13:10:05 -08:00
Junio C Hamano 0bbab7d2ab Merge branch 'rs/lose-leak-pending'
API clean-up around revision traversal.

* rs/lose-leak-pending:
  commit: remove unused function clear_commit_marks_for_object_array()
  revision: remove the unused flag leak_pending
  checkout: avoid using the rev_info flag leak_pending
  bundle: avoid using the rev_info flag leak_pending
  bisect: avoid using the rev_info flag leak_pending
  object: add clear_commit_marks_all()
  ref-filter: use clear_commit_marks_many() in do_merge_filter()
  commit: use clear_commit_marks_many() in remove_redundant()
  commit: avoid allocation in clear_commit_marks_many()
2018-01-23 13:16:36 -08:00
René Scharfe 4ad315fc99 object: add clear_commit_marks_all()
Add a function for clearing the commit marks of all in-core commit
objects.  It's similar to clear_object_flags(), but more precise, since
it leaves the other object types alone.  It still has to iterate through
them, though.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-28 13:50:05 -08:00
Jeff Hostetler 25ec7bcac0 list-objects: filter objects in traverse_commit_list
Create traverse_commit_list_filtered() and add filtering
interface to allow certain objects to be omitted from the
traversal.

Update traverse_commit_list() to be a wrapper for the above
with a null filter to minimize the number of callers that
needed to be changed.

Object filtering will be used in a future commit by rev-list
and pack-objects for partial clone and fetch to omit unwanted
objects from the result.

traverse_bitmap_commit_list() does not work with filtering.
If a packfile bitmap is present, it will not be used.  It
should be possible to extend such support in the future (at
least to simple filters that do not require object pathnames),
but that is beyond the scope of this patch series.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-11-22 14:11:57 +09:00
Martin Ågren 7199203937 object_array: add and use `object_array_pop()`
In a couple of places, we pop objects off an object array `foo` by
decreasing `foo.nr`. We access `foo.nr` in many places, but most if not
all other times we do so read-only, e.g., as we iterate over the array.
But when we change `foo.nr` behind the array's back, it feels a bit
nasty and looks like it might leak memory.

Leaks happen if the popped element has an allocated `name` or `path`.
At the moment, that is not the case. Still, 1) the object array might
gain more fields that want to be freed, 2) a code path where we pop
might start using names or paths, 3) one of these code paths might be
copied to somewhere where we do, and 4) using a dedicated function for
popping is conceptually cleaner.

Introduce and use `object_array_pop()` instead. Release memory in the
new function. Document that popping an object leaves the associated
elements in limbo.

The converted places were identified by grepping for "\.nr\>" and
looking for "--".

Make the new function return NULL on an empty array. This is consistent
with `pop_commit()` and allows the following:

	while ((o = object_array_pop(&foo)) != NULL) {
		// do something
	}

But as noted above, we don't need to go out of our way to avoid reading
`foo.nr`. This is probably more readable:

	while (foo.nr) {
		... o = object_array_pop(&foo);
		// do something
	}

The name of `object_array_pop()` does not quite align with
`add_object_array()`. That is unfortunate. On the other hand, it matches
`object_array_clear()`. Arguably it's `add_...` that is the odd one out,
since it reads like it's used to "add" an "object array". For that
reason, side with `object_array_clear()`.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-09-24 10:06:04 +09:00
Jonathan Tan 092c55d094 object: remove "used" field from struct object
The "used" field in struct object is only used by builtin/fsck. Remove
that field and modify builtin/fsck to use a flag instead.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-20 14:54:08 -07:00
brian m. carlson c251c83df2 object: convert parse_object* to take struct object_id
Make parse_object, parse_object_or_die, and parse_object_buffer take a
pointer to struct object_id.  Remove the temporary variables inserted
earlier, since they are no longer necessary.  Transform all of the
callers using the following semantic patch:

@@
expression E1;
@@
- parse_object(E1.hash)
+ parse_object(&E1)

@@
expression E1;
@@
- parse_object(E1->hash)
+ parse_object(E1)

@@
expression E1, E2;
@@
- parse_object_or_die(E1.hash, E2)
+ parse_object_or_die(&E1, E2)

@@
expression E1, E2;
@@
- parse_object_or_die(E1->hash, E2)
+ parse_object_or_die(E1, E2)

@@
expression E1, E2, E3, E4, E5;
@@
- parse_object_buffer(E1.hash, E2, E3, E4, E5)
+ parse_object_buffer(&E1, E2, E3, E4, E5)

@@
expression E1, E2, E3, E4, E5;
@@
- parse_object_buffer(E1->hash, E2, E3, E4, E5)
+ parse_object_buffer(E1, E2, E3, E4, E5)

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-08 15:12:58 +09:00
Jeff King 41a078c60b fetch-pack: cache results of for_each_alternate_ref
We may run for_each_alternate_ref() twice, once in
find_common() and once in everything_local(). This operation
can be expensive, because it involves running a sub-process
which must freshly load all of the alternate's refs from
disk.

Let's cache and reuse the results between the two calls. We
can make some optimizations based on the particular use
pattern in fetch-pack to keep our memory usage down.

The first is that we only care about the sha1s, not the refs
themselves. So it's OK to store only the sha1s, and to
suppress duplicates. The natural fit would therefore be a
sha1_array.

However, sha1_array's de-duplication happens only after it
has read and sorted all entries. It still stores each
duplicate. For an alternate with a large number of refs
pointing to the same commits, this is a needless expense.

Instead, we'd prefer to eliminate duplicates before putting
them in the cache, which implies using a hash. We can
further note that fetch-pack will call parse_object() on
each alternate sha1. We can therefore keep our cache as a
set of pointers to "struct object". That gives us a place to
put our "already seen" bit with an optimized hash lookup.
And as a bonus, the object stores the sha1 for us, so
pointer-to-object is all we need.

There are two extra optimizations I didn't do here:

  - we actually store an array of pointer-to-object.
    Technically we could just walk the obj_hash table
    looking for entries with the ALTERNATE flag set (because
    our use case doesn't care about the order here).

    But that hash table may be mostly composed of
    non-ALTERNATE entries, so we'd waste time walking over
    them. So it would be a slight win in memory use, but a
    loss in CPU.

  - the items we pull out of the cache are actual "struct
    object"s, but then we feed "obj->sha1" to our
    sub-functions, which promptly call parse_object().

    This second parse is cheap, because it starts with
    lookup_object() and will bail immediately when it sees
    we've already parsed the object. We could save the extra
    hash lookup, but it would involve refactoring the
    functions we call. It may or may not be worth the
    trouble.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-08 15:39:55 -08:00
Nguyễn Thái Ngọc Duy 079aa97e24 upload-pack: add get_reachable_list()
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-13 14:38:16 -07:00
brian m. carlson ed1c9977cb Remove get_object_hash.
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>
2015-11-20 08:02:05 -05:00
brian m. carlson f2fd0760f6 Convert struct object to object_id
struct object is one of the major data structures dealing with object
IDs.  Convert it to use struct object_id instead of an unsigned char
array.  Convert get_object_hash to refer to the new member as well.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Jeff King <peff@peff.net>
2015-11-20 08:02:05 -05:00
brian m. carlson 3c4270107f object: introduce get_object_hash macro.
This macro is a temporary change to ease the transition of struct object
to use struct object_id.  It takes an argument of struct object and
returns the object's hash.  Provide this hash next to struct object for
easier conversion.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Jeff King <peff@peff.net>
2015-11-20 08:02:05 -05:00
Jeff King 189a122249 drop add_object_array_with_mode
This is a thin compatibility wrapper around
add_pending_object_with_path. But the only caller is
add_object_array, which is itself just a thin compatibility
wrapper. There are no external callers, so we can just
remove this middle wrapper.

Noticed-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-19 15:28:30 -07:00
Jeff King 9e0c3c4fcd make add_object_array_with_context interface more sane
When you resolve a sha1, you can optionally keep any context
found during the resolution, including the path and mode of
a tree entry (e.g., when looking up "HEAD:subdir/file.c").

The add_object_array_with_context function lets you then
attach that context to an entry in a list. Unfortunately,
the interface for doing so is horrible. The object_context
structure is large and most object_array users do not use
it. Therefore we keep a pointer to the structure to avoid
burdening other users too much. But that means when we do
use it that we must allocate the struct ourselves. And the
struct contains a fixed PATH_MAX-sized buffer, which makes
this wholly unsuitable for any large arrays.

We can observe that there is only a single user of the
"with_context" variant: builtin/grep.c. And in that use
case, the only element we care about is the path. We can
therefore store only the path as a pointer (the context's
mode field was redundant with the object_array_entry itself,
and nobody actually cared about the surrounding tree). This
still requires a strdup of the pathname, but at least we are
only consuming the minimum amount of memory for each string.

We can also handle the copying ourselves in
add_object_array_*, and free it as appropriate in
object_array_release_entry.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-16 10:10:44 -07:00
Jeff King 46be823124 object_array: add a "clear" function
There's currently no easy way to free the memory associated
with an object_array (and in most cases, we simply leak the
memory in a rev_info's pending array). Let's provide a
helper to make this easier to handle.

We can make use of it in list-objects.c, which does the same
thing by hand (but fails to free the "name" field of each
entry, potentially leaking memory).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-10-16 10:10:37 -07:00
Johannes Schindelin fe8e3b7180 Refactor type_from_string() to allow continuing after detecting an error
In the next commits, we will enhance the fsck_tag() function to check
tag objects more thoroughly. To this end, we need a function to verify
that a given string is a valid object type, but that does not die() in
the negative case.

While at it, prepare type_from_string() for counted strings, i.e. strings
with an explicitly specified length rather than a NUL termination.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-09-10 13:52:13 -07:00
Jeff King 8ff226a9d5 add object_as_type helper for casting objects
When we call lookup_commit, lookup_tree, etc, the logic goes
something like:

  1. Look for an existing object struct. If we don't have
     one, allocate and return a new one.

  2. Double check that any object we have is the expected
     type (and complain and return NULL otherwise).

  3. Convert an object with type OBJ_NONE (from a prior
     call to lookup_unknown_object) to the expected type.

We can encapsulate steps 2 and 3 in a helper function which
checks whether we have the expected object type, converts
OBJ_NONE as appropriate, and returns the object.

Not only does this shorten the code, but it also provides
one central location for converting OBJ_NONE objects into
objects of other types. Future patches will use that to
enforce type-specific invariants.

Since this is a refactoring, we would want it to behave
exactly as the current code. It takes a little reasoning to
see that this is the case:

  - for lookup_{commit,tree,etc} functions, we are just
    pulling steps 2 and 3 into a function that does the same
    thing.

  - for the call in peel_object, we currently only do step 3
    (but we want to consolidate it with the others, as
    mentioned above). However, step 2 is a noop here, as the
    surrounding conditional makes sure we have OBJ_NONE
    (which we want to keep to avoid an extraneous call to
    sha1_object_info).

  - for the call in lookup_commit_reference_gently, we are
    currently doing step 2 but not step 3. However, step 3
    is a noop here. The object we got will have just come
    from deref_tag, which must have figured out the type for
    each object in order to know when to stop peeling.
    Therefore the type will never be OBJ_NONE.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-13 18:59:05 -07:00
Jeff King d36f51c13b move setting of object->type to alloc_* functions
The "struct object" type implements basic object
polymorphism.  Individual instances are allocated as
concrete types (or as a union type that can store any
object), and a "struct object *" can be cast into its real
type after examining its "type" enum.  This means it is
dangerous to have a type field that does not match the
allocation (e.g., setting the type field of a "struct blob"
to "OBJ_COMMIT" would mean that a reader might read past the
allocated memory).

In most of the current code this is not a problem; the first
thing we do after allocating an object is usually to set its
type field by passing it to create_object. However, the
virtual commits we create in merge-recursive.c do not ever
get their type set. This does not seem to have caused
problems in practice, though (presumably because we always
pass around a "struct commit" pointer and never even look at
the type).

We can fix this oversight and also make it harder for future
code to get it wrong by setting the type directly in the
object allocation functions.

This will also make it easier to fix problems with commit
index allocation, as we know that any object allocated by
alloc_commit_node will meet the invariant that an object
with an OBJ_COMMIT type field will have a unique index
number.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-13 18:59:05 -07:00
Junio C Hamano b407d40933 Merge branch 'nd/log-show-linear-break'
Attempts to show where a single-strand-of-pearls break in "git log"
output.

* nd/log-show-linear-break:
  log: add --show-linear-break to help see non-linear history
  object.h: centralize object flag allocation
2014-04-03 12:38:11 -07:00
Nguyễn Thái Ngọc Duy 1b32decefd log: add --show-linear-break to help see non-linear history
Option explanation is in rev-list-options.txt. The interaction with -z
is left undecided.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-25 15:09:49 -07:00
Nguyễn Thái Ngọc Duy 208acbfb82 object.h: centralize object flag allocation
While the field "flags" is mainly used by the revision walker, it is
also used in many other places. Centralize the whole flag allocation to
one place for a better overview (and easier to move flags if we have
too).

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-25 15:09:24 -07:00
Michael Haggerty 33bef7ea25 Document some functions defined in object.c
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-02-28 13:18:09 -08:00
Junio C Hamano 4197361e39 Merge branch 'mg/more-textconv'
Make "git grep" and "git show" pay attention to --textconv when
dealing with blob objects.

* mg/more-textconv:
  grep: honor --textconv for the case rev:path
  grep: allow to use textconv filters
  t7008: demonstrate behavior of grep with textconv
  cat-file: do not die on --textconv without textconv filters
  show: honor --textconv for blobs
  diff_opt: track whether flags have been set explicitly
  t4030: demonstrate behavior of show with textconv
2013-10-23 13:21:31 -07:00
Michael Haggerty 31faeb2088 object_array_entry: fix memory handling of the name field
Previously, the memory management of the object_array_entry::name
field was inconsistent and undocumented.  object_array_entries are
ultimately created by a single function, add_object_array_with_mode(),
which has an argument "const char *name".  This function used to
simply set the name field to reference the string pointed to by the
name parameter, and nobody on the object_array side ever freed the
memory.  Thus, it assumed that the memory for the name field would be
managed by the caller, and that the lifetime of that string would be
at least as long as the lifetime of the object_array_entry.  But
callers were inconsistent:

* Some passed pointers to constant strings or argv entries, which was
  OK.

* Some passed pointers to newly-allocated memory, but didn't arrange
  for the memory ever to be freed.

* Some passed the return value of sha1_to_hex(), which is a pointer to
  a statically-allocated buffer that can be overwritten at any time.

* Some passed pointers to refnames that they received from a
  for_each_ref()-type iteration, but the lifetimes of such refnames is
  not guaranteed by the refs API.

Bring consistency to this mess by changing object_array to make its
own copy for the object_array_entry::name field and free this memory
when an object_array_entry is deleted from the array.

Many callers were passing the empty string as the name parameter, so
as a performance optimization, treat the empty string specially.
Instead of making a copy, store a pointer to a statically-allocated
empty string to object_array_entry::name.  When deleting such an
entry, skip the free().

Change the callers that were already passing copies to
add_object_array_with_mode() to either skip the copy, or (if the
memory needed to be allocated anyway) freeing the memory itself.

A part of this commit effectively reverts

    70d26c6e76 read_revisions_from_stdin: make copies for handle_revision_arg

because the copying introduced by that commit (which is still
necessary) is now done at a deeper level.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-06-02 15:28:46 -07:00