Commit Graph

1810 Commits

Author SHA1 Message Date
Junio C Hamano
30cf1911e2 Merge branch 'js/vscode'
Add a script (in contrib/) to help users of VSCode work better with
our codebase.

* js/vscode:
  vscode: let cSpell work on commit messages, too
  vscode: add a dictionary for cSpell
  vscode: use 8-space tabs, no trailing ws, etc for Git's source code
  vscode: wrap commit messages at column 72 by default
  vscode: only overwrite C/C++ settings
  mingw: define WIN32 explicitly
  cache.h: extract enum declaration from inside a struct declaration
  vscode: hard-code a couple defines
  contrib: add a script to initialize VS Code configuration
2018-08-15 15:08:26 -07:00
Junio C Hamano
1689c22c1c Merge branch 'jk/core-use-replace-refs'
A new configuration variable core.usereplacerefs has been added,
primarily to help server installations that want to ignore the
replace mechanism altogether.

* jk/core-use-replace-refs:
  add core.usereplacerefs config option
  check_replace_refs: rename to read_replace_refs
  check_replace_refs: fix outdated comment
2018-08-15 15:08:23 -07:00
Junio C Hamano
78a72ad4f8 Merge branch 'jt/commit-graph-per-object-store'
The singleton commit-graph in-core instance is made per in-core
repository instance.

* jt/commit-graph-per-object-store:
  commit-graph: add repo arg to graph readers
  commit-graph: store graph in struct object_store
  commit-graph: add free_commit_graph
  commit-graph: add missing forward declaration
  object-store: add missing include
  commit-graph: refactor preparing commit graph
2018-08-02 15:30:47 -07:00
Junio C Hamano
c18ac30e9e Merge branch 'en/dirty-merge-fixes'
The recursive merge strategy did not properly ensure there was no
change between HEAD and the index before performing its operation,
which has been corrected.

* en/dirty-merge-fixes:
  merge: fix misleading pre-merge check documentation
  merge-recursive: enforce rule that index matches head before merging
  t6044: add more testcases with staged changes before a merge is invoked
  merge-recursive: fix assumption that head tree being merged is HEAD
  merge-recursive: make sure when we say we abort that we actually abort
  t6044: add a testcase for index matching head, when head doesn't match HEAD
  t6044: verify that merges expected to abort actually abort
  index_has_changes(): avoid assuming operating on the_index
  read-cache.c: move index_has_changes() from merge.c
2018-08-02 15:30:45 -07:00
Junio C Hamano
ae533c4a92 Merge branch 'jm/cache-entry-from-mem-pool'
For a large tree, the index needs to hold many cache entries
allocated on heap.  These cache entries are now allocated out of a
dedicated memory pool to amortize malloc(3) overhead.

* jm/cache-entry-from-mem-pool:
  block alloc: add validations around cache_entry lifecyle
  block alloc: allocate cache entries from mem_pool
  mem-pool: fill out functionality
  mem-pool: add life cycle management functions
  mem-pool: only search head block for available space
  block alloc: add lifecycle APIs for cache_entry structs
  read-cache: teach make_cache_entry to take object_id
  read-cache: teach refresh_cache_entry to take istate
2018-08-02 15:30:43 -07:00
Junio C Hamano
37aac3e408 Merge branch 'bc/object-id'
Conversion from uchar[40] to struct object_id continues.

* bc/object-id:
  pretty: switch hard-coded constants to the_hash_algo
  sha1-file: convert constants to uses of the_hash_algo
  log-tree: switch GIT_SHA1_HEXSZ to the_hash_algo->hexsz
  diff: switch GIT_SHA1_HEXSZ to use the_hash_algo
  builtin/merge-recursive: make hash independent
  builtin/merge: switch to use the_hash_algo
  builtin/fmt-merge-msg: make hash independent
  builtin/update-index: simplify parsing of cacheinfo
  builtin/update-index: convert to using the_hash_algo
  refs/files-backend: use the_hash_algo for writing refs
  sha1-name: use the_hash_algo when parsing object names
  strbuf: allocate space with GIT_MAX_HEXSZ
  commit: express tree entry constants in terms of the_hash_algo
  hex: switch to using the_hash_algo
  tree-walk: replace hard-coded constants with the_hash_algo
  cache: update object ID functions for the_hash_algo
2018-08-02 15:30:39 -07:00
Johannes Schindelin
58930fdb19 cache.h: extract enum declaration from inside a struct declaration
While it is technically possible, it is confusing. Not only the user,
but also VS Code's intellisense.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-30 13:14:38 -07:00
Jeff King
6ebd1cafe2 check_replace_refs: rename to read_replace_refs
This was added as a NEEDSWORK in c3c36d7de2 (replace-object:
check_replace_refs is safe in multi repo environment, 2018-04-11),
waiting for a calmer period. Since doing so now doesn't conflict
with anything in 'pu', it seems as good a time as any.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-18 15:45:14 -07:00
Jeff King
72470aa38a check_replace_refs: fix outdated comment
Commit afc711b8e1 (rename read_replace_refs to
check_replace_refs, 2014-02-18) added a comment mentioning
that check_replace_refs is set in two ways:

  - from user intent via --no-replace-objects, etc

  - after seeing there are no replace refs to respect

Since c3c36d7de2 (replace-object: check_replace_refs is safe
in multi repo environment, 2018-04-11) the second is no
longer true. Let's drop that part of the comment.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-18 15:45:06 -07:00
Junio C Hamano
00624d608c Merge branch 'sb/object-store-grafts'
The conversion to pass "the_repository" and then "a_repository"
throughout the object access API continues.

* 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
2018-07-18 12:20:28 -07:00
Jonathan Tan
dade47c06c commit-graph: add repo arg to graph readers
Add a struct repository argument to the functions in commit-graph.h that
read the commit graph. (This commit does not affect functions that write
commit graphs.)

Because the commit graph functions can now read the commit graph of any
repository, the global variable core_commit_graph has been removed.
Instead, the config option core.commitGraph is now read on the first
time in a repository that a commit is attempted to be parsed using its
commit graph.

This commit includes a test that exercises the functionality on an
arbitrary repository that is not the_repository.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-17 15:47:48 -07:00
brian m. carlson
509f6f62a4 cache: update object ID functions for the_hash_algo
Most of our code has been converted to use struct object_id for object
IDs.  However, there are some places that still have not, and there are
a variety of places that compare equivalently sized hashes that are not
object IDs.  All of these hashes are artifacts of the internal hash
algorithm in use, and when we switch to NewHash for object storage, all
of these uses will also switch.

Update the hashcpy, hashclr, and hashcmp functions to use the_hash_algo,
since they are used in a variety of places to copy and manipulate
buffers that need to move data into or out of struct object_id.  This
has the effect of making the corresponding oid* functions use
the_hash_algo as well.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-16 14:27:38 -07:00
Elijah Newren
e1f8694f33 merge-recursive: fix assumption that head tree being merged is HEAD
`git merge-recursive` does a three-way merge between user-specified trees
base, head, and remote.  Since the user is allowed to specify head, we can
not necesarily assume that head == HEAD.

Modify index_has_changes() to take an extra argument specifying the tree
to compare against.  If NULL, it will compare to HEAD.  We then use this
from merge-recursive to make sure we compare to the user-specified head.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-11 09:38:36 -07:00
Elijah Newren
1b9fbefbe0 index_has_changes(): avoid assuming operating on the_index
Modify index_has_changes() to take a struct istate* instead of just
operating on the_index.  This is only a partial conversion, though,
because we call do_diff_cache() which implicitly assumes work is to be
done on the_index.  Ongoing work is being done elsewhere to do the
remainder of the conversion, and thus is not duplicated here.  Instead,
a simple check is put in place until that work is complete.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 13:13:18 -07:00
Jameson Miller
8616a2d0cb block alloc: add validations around cache_entry lifecyle
Add an option (controlled by an environment variable) perform extra
validations on mem_pool allocated cache entries. When set:

  1) Invalidate cache_entry memory when discarding cache_entry.

  2) When discarding index_state struct, verify that all cache_entries
     were allocated from expected mem_pool.

  3) When discarding mem_pools, invalidate mem_pool memory.

This should provide extra checks that mem_pools and their allocated
cache_entries are being used as expected.

Signed-off-by: Jameson Miller <jamill@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 10:58:27 -07:00
Jameson Miller
8e72d67529 block alloc: allocate cache entries from mem_pool
When reading large indexes from disk, a portion of the time is
dominated in malloc() calls. This can be mitigated by allocating a
large block of memory and manage it ourselves via memory pools.

This change moves the cache entry allocation to be on top of memory
pools.

Design:

The index_state struct will gain a notion of an associated memory_pool
from which cache_entries will be allocated from. When reading in the
index from disk, we have information on the number of entries and
their size, which can guide us in deciding how large our initial
memory allocation should be. When an index is discarded, the
associated memory_pool will be discarded as well - so the lifetime of
a cache_entry is tied to the lifetime of the index_state that it was
allocated for.

In the case of a Split Index, the following rules are followed. 1st,
some terminology is defined:

Terminology:
  - 'the_index': represents the logical view of the index

  - 'split_index': represents the "base" cache entries. Read from the
    split index file.

'the_index' can reference a single split_index, as well as
cache_entries from the split_index. `the_index` will be discarded
before the `split_index` is.  This means that when we are allocating
cache_entries in the presence of a split index, we need to allocate
the entries from the `split_index`'s memory pool.  This allows us to
follow the pattern that `the_index` can reference cache_entries from
the `split_index`, and that the cache_entries will not be freed while
they are still being referenced.

Managing transient cache_entry structs:
Cache entries are usually allocated for an index, but this is not always
the case. Cache entries are sometimes allocated because this is the
type that the existing checkout_entry function works with. Because of
this, the existing code needs to handle cache entries associated with an
index / memory pool, and those that only exist transiently. Several
strategies were contemplated around how to handle this:

Chosen approach:
An extra field was added to the cache_entry type to track whether the
cache_entry was allocated from a memory pool or not. This is currently
an int field, as there are no more available bits in the existing
ce_flags bit field. If / when more bits are needed, this new field can
be turned into a proper bit field.

Alternatives:

1) Do not include any information about how the cache_entry was
allocated. Calling code would be responsible for tracking whether the
cache_entry needed to be freed or not.
  Pro: No extra memory overhead to track this state
  Con: Extra complexity in callers to handle this correctly.

The extra complexity and burden to not regress this behavior in the
future was more than we wanted.

2) cache_entry would gain knowledge about which mem_pool allocated it
  Pro: Could (potentially) do extra logic to know when a mem_pool no
       longer had references to any cache_entry
  Con: cache_entry would grow heavier by a pointer, instead of int

We didn't see a tangible benefit to this approach

3) Do not add any extra information to a cache_entry, but when freeing a
   cache entry, check if the memory exists in a region managed by existing
   mem_pools.
  Pro: No extra memory overhead to track state
  Con: Extra computation is performed when freeing cache entries

We decided tracking and iterating over known memory pool regions was
less desirable than adding an extra field to track this stae.

Signed-off-by: Jameson Miller <jamill@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 10:58:27 -07:00
Jameson Miller
a849735bfb block alloc: add lifecycle APIs for cache_entry structs
It has been observed that the time spent loading an index with a large
number of entries is partly dominated by malloc() calls. This change
is in preparation for using memory pools to reduce the number of
malloc() calls made to allocate cahce entries when loading an index.

Add an API to allocate and discard cache entries, abstracting the
details of managing the memory backing the cache entries. This commit
does actually change how memory is managed - this will be done in a
later commit in the series.

This change makes the distinction between cache entries that are
associated with an index and cache entries that are not associated with
an index. A main use of cache entries is with an index, and we can
optimize the memory management around this. We still have other cases
where a cache entry is not persisted with an index, and so we need to
handle the "transient" use case as well.

To keep the congnitive overhead of managing the cache entries, there
will only be a single discard function. This means there must be enough
information kept with the cache entry so that we know how to discard
them.

A summary of the main functions in the API is:

make_cache_entry: create cache entry for use in an index. Uses specified
                  parameters to populate cache_entry fields.

make_empty_cache_entry: Create an empty cache entry for use in an index.
                        Returns cache entry with empty fields.

make_transient_cache_entry: create cache entry that is not used in an
                            index. Uses specified parameters to populate
                            cache_entry fields.

make_empty_transient_cache_entry: create cache entry that is not used in
                                  an index. Returns cache entry with
                                  empty fields.

discard_cache_entry: A single function that knows how to discard a cache
                     entry regardless of how it was allocated.

Signed-off-by: Jameson Miller <jamill@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 10:58:27 -07:00
Jameson Miller
825ed4d9a0 read-cache: teach make_cache_entry to take object_id
Teach make_cache_entry function to take object_id instead of a SHA-1.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 10:58:15 -07:00
Jameson Miller
768d796506 read-cache: teach refresh_cache_entry to take istate
Refactor refresh_cache_entry() to work on a specific index, instead of
implicitly using the_index. This is in preparation for making the
make_cache_entry function apply to a specific index.

Signed-off-by: Jameson Miller <jamill@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 10:58:15 -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
2289880f78 Merge branch 'nd/command-list'
The list of commands with their various attributes were spread
across a few places in the build procedure, but it now is getting a
bit more consolidated to allow more automation.

* nd/command-list:
  completion: allow to customize the completable command list
  completion: add and use --list-cmds=alias
  completion: add and use --list-cmds=nohelpers
  Move declaration for alias.c to alias.h
  completion: reduce completable command list
  completion: let git provide the completable command list
  command-list.txt: documentation and guide line
  help: use command-list.txt for the source of guides
  help: add "-a --verbose" to list all commands with synopsis
  git: support --list-cmds=list-<category>
  completion: implement and use --list-cmds=main,others
  git --list-cmds: collect command list in a string_list
  git.c: convert --list-* to --list-cmds=*
  Remove common-cmds.h
  help: use command-list.h for common command list
  generate-cmds.sh: export all commands to command-list.h
  generate-cmds.sh: factor out synopsis extract code
2018-06-01 15:06:37 +09:00
Junio C Hamano
42c8ce1c49 Merge branch 'bc/object-id'
Conversion from uchar[20] to struct object_id continues.

* bc/object-id: (42 commits)
  merge-one-file: compute empty blob object ID
  add--interactive: compute the empty tree value
  Update shell scripts to compute empty tree object ID
  sha1_file: only expose empty object constants through git_hash_algo
  dir: use the_hash_algo for empty blob object ID
  sequencer: use the_hash_algo for empty tree object ID
  cache-tree: use is_empty_tree_oid
  sha1_file: convert cached object code to struct object_id
  builtin/reset: convert use of EMPTY_TREE_SHA1_BIN
  builtin/receive-pack: convert one use of EMPTY_TREE_SHA1_HEX
  wt-status: convert two uses of EMPTY_TREE_SHA1_HEX
  submodule: convert several uses of EMPTY_TREE_SHA1_HEX
  sequencer: convert one use of EMPTY_TREE_SHA1_HEX
  merge: convert empty tree constant to the_hash_algo
  builtin/merge: switch tree functions to use object_id
  builtin/am: convert uses of EMPTY_TREE_SHA1_BIN to the_hash_algo
  sha1-file: add functions for hex empty tree and blob OIDs
  builtin/receive-pack: avoid hard-coded constants for push certs
  diff: specify abbreviation size in terms of the_hash_algo
  upload-pack: replace use of several hard-coded constants
  ...
2018-05-30 14:04:10 +09:00
Junio C Hamano
7913f53b56 Sync with Git 2.17.1
* maint: (25 commits)
  Git 2.17.1
  Git 2.16.4
  Git 2.15.2
  Git 2.14.4
  Git 2.13.7
  fsck: complain when .gitmodules is a symlink
  index-pack: check .gitmodules files with --strict
  unpack-objects: call fsck_finish() after fscking objects
  fsck: call fsck_finish() after fscking objects
  fsck: check .gitmodules content
  fsck: handle promisor objects in .gitmodules check
  fsck: detect gitmodules files
  fsck: actually fsck blob data
  fsck: simplify ".git" check
  index-pack: make fsck error message more specific
  verify_path: disallow symlinks in .gitmodules
  update-index: stat updated files earlier
  verify_dotfile: mention case-insensitivity in comment
  verify_path: drop clever fallthrough
  skip_prefix: add case-insensitive variant
  ...
2018-05-29 17:10:05 +09:00
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
Junio C Hamano
fcb6df3254 Merge branch 'sb/oid-object-info'
The codepath around object-info API has been taught to take the
repository object (which in turn tells the API which object store
the objects are to be located).

* sb/oid-object-info:
  cache.h: allow oid_object_info to handle arbitrary repositories
  packfile: add repository argument to cache_or_unpack_entry
  packfile: add repository argument to unpack_entry
  packfile: add repository argument to read_object
  packfile: add repository argument to packed_object_info
  packfile: add repository argument to packed_to_object_type
  packfile: add repository argument to retry_bad_packed_offset
  cache.h: add repository argument to oid_object_info
  cache.h: add repository argument to oid_object_info_extended
2018-05-23 14:38:16 +09:00
Junio C Hamano
b577198526 Merge branch 'nd/pack-format-doc'
Doc update.

* nd/pack-format-doc:
  pack-format.txt: more details on pack file format
2018-05-23 14:38:11 +09:00
Junio C Hamano
68f95b26e4 Sync with Git 2.16.4
* maint-2.16:
  Git 2.16.4
  Git 2.15.2
  Git 2.14.4
  Git 2.13.7
  verify_path: disallow symlinks in .gitmodules
  update-index: stat updated files earlier
  verify_dotfile: mention case-insensitivity in comment
  verify_path: drop clever fallthrough
  skip_prefix: add case-insensitive variant
  is_{hfs,ntfs}_dotgitmodules: add tests
  is_ntfs_dotgit: match other .git files
  is_hfs_dotgit: match other .git files
  is_ntfs_dotgit: use a size_t for traversing string
  submodule-config: verify submodule names as paths
2018-05-22 14:25:26 +09:00
Junio C Hamano
023020401d Sync with Git 2.15.2
* maint-2.15:
  Git 2.15.2
  Git 2.14.4
  Git 2.13.7
  verify_path: disallow symlinks in .gitmodules
  update-index: stat updated files earlier
  verify_dotfile: mention case-insensitivity in comment
  verify_path: drop clever fallthrough
  skip_prefix: add case-insensitive variant
  is_{hfs,ntfs}_dotgitmodules: add tests
  is_ntfs_dotgit: match other .git files
  is_hfs_dotgit: match other .git files
  is_ntfs_dotgit: use a size_t for traversing string
  submodule-config: verify submodule names as paths
2018-05-22 14:18:06 +09:00
Junio C Hamano
9e0f06d55d Sync with Git 2.14.4
* maint-2.14:
  Git 2.14.4
  Git 2.13.7
  verify_path: disallow symlinks in .gitmodules
  update-index: stat updated files earlier
  verify_dotfile: mention case-insensitivity in comment
  verify_path: drop clever fallthrough
  skip_prefix: add case-insensitive variant
  is_{hfs,ntfs}_dotgitmodules: add tests
  is_ntfs_dotgit: match other .git files
  is_hfs_dotgit: match other .git files
  is_ntfs_dotgit: use a size_t for traversing string
  submodule-config: verify submodule names as paths
2018-05-22 14:15:14 +09:00
Junio C Hamano
7b01c71b64 Sync with Git 2.13.7
* maint-2.13:
  Git 2.13.7
  verify_path: disallow symlinks in .gitmodules
  update-index: stat updated files earlier
  verify_dotfile: mention case-insensitivity in comment
  verify_path: drop clever fallthrough
  skip_prefix: add case-insensitive variant
  is_{hfs,ntfs}_dotgitmodules: add tests
  is_ntfs_dotgit: match other .git files
  is_hfs_dotgit: match other .git files
  is_ntfs_dotgit: use a size_t for traversing string
  submodule-config: verify submodule names as paths
2018-05-22 14:10:49 +09:00
Jeff King
10ecfa7649 verify_path: disallow symlinks in .gitmodules
There are a few reasons it's not a good idea to make
.gitmodules a symlink, including:

  1. It won't be portable to systems without symlinks.

  2. It may behave inconsistently, since Git may look at
     this file in the index or a tree without bothering to
     resolve any symbolic links. We don't do this _yet_, but
     the config infrastructure is there and it's planned for
     the future.

With some clever code, we could make (2) work. And some
people may not care about (1) if they only work on one
platform. But there are a few security reasons to simply
disallow it:

  a. A symlinked .gitmodules file may circumvent any fsck
     checks of the content.

  b. Git may read and write from the on-disk file without
     sanity checking the symlink target. So for example, if
     you link ".gitmodules" to "../oops" and run "git
     submodule add", we'll write to the file "oops" outside
     the repository.

Again, both of those are problems that _could_ be solved
with sufficient code, but given the complications in (1) and
(2), we're better off just outlawing it explicitly.

Note the slightly tricky call to verify_path() in
update-index's update_one(). There we may not have a mode if
we're not updating from the filesystem (e.g., we might just
be removing the file). Passing "0" as the mode there works
fine; since it's not a symlink, we'll just skip the extra
checks.

Signed-off-by: Jeff King <peff@peff.net>
2018-05-21 23:50:11 -04:00
Johannes Schindelin
e7cb0b4455 is_ntfs_dotgit: match other .git files
When we started to catch NTFS short names that clash with .git, we only
looked for GIT~1. This is sufficient because we only ever clone into an
empty directory, so .git is guaranteed to be the first subdirectory or
file in that directory.

However, even with a fresh clone, .gitmodules is *not* necessarily the
first file to be written that would want the NTFS short name GITMOD~1: a
malicious repository can add .gitmodul0000 and friends, which sorts
before `.gitmodules` and is therefore checked out *first*. For that
reason, we have to test not only for ~1 short names, but for others,
too.

It's hard to just adapt the existing checks in is_ntfs_dotgit(): since
Windows 2000 (i.e., in all Windows versions still supported by Git),
NTFS short names are only generated in the <prefix>~<number> form up to
number 4. After that, a *different* prefix is used, calculated from the
long file name using an undocumented, but stable algorithm.

For example, the short name of .gitmodules would be GITMOD~1, but if it
is taken, and all of ~2, ~3 and ~4 are taken, too, the short name
GI7EBA~1 will be used. From there, collisions are handled by
incrementing the number, shortening the prefix as needed (until ~9999999
is reached, in which case NTFS will not allow the file to be created).

We'd also want to handle .gitignore and .gitattributes, which suffer
from a similar problem, using the fall-back short names GI250A~1 and
GI7D29~1, respectively.

To accommodate for that, we could reimplement the hashing algorithm, but
it is just safer and simpler to provide the known prefixes. This
algorithm has been reverse-engineered and described at
https://usn.pw/blog/gen/2015/06/09/filenames/, which is defunct but
still available via https://web.archive.org/.

These can be recomputed by running the following Perl script:

-- snip --
use warnings;
use strict;

sub compute_short_name_hash ($) {
        my $checksum = 0;
        foreach (split('', $_[0])) {
                $checksum = ($checksum * 0x25 + ord($_)) & 0xffff;
        }

        $checksum = ($checksum * 314159269) & 0xffffffff;
        $checksum = 1 + (~$checksum & 0x7fffffff) if ($checksum & 0x80000000);
        $checksum -= (($checksum * 1152921497) >> 60) * 1000000007;

        return scalar reverse sprintf("%x", $checksum & 0xffff);
}

print compute_short_name_hash($ARGV[0]);
-- snap --

E.g., running that with the argument ".gitignore" will
result in "250a" (which then becomes "gi250a" in the code).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Jeff King <peff@peff.net>
2018-05-21 23:50:11 -04:00
Nguyễn Thái Ngọc Duy
65b5f9483e Move declaration for alias.c to alias.h
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-21 13:23:14 +09:00
Stefan Beller
0437a2e365 cache: convert get_graft_file to handle arbitrary repositories
This conversion was done without the #define trick used in the earlier
series refactoring to have better repository access, because this function
is easy to review, as all lines are converted and it has only one caller.

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
cbd53a2193 object-store: move object access functions to object-store.h
This should make these functions easier to find and cache.h less
overwhelming to read.

In particular, this moves:
- read_object_file
- oid_object_info
- write_object_file

As a result, most of the codebase needs to #include object-store.h.
In this patch the #include is only added to files that would fail to
compile otherwise.  It would be better to #include wherever
identifiers from the header are used.  That can happen later
when we have better tooling for it.

Signed-off-by: Stefan Beller <sbeller@google.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
Nguyễn Thái Ngọc Duy
011b648646 pack-format.txt: more details on pack file format
The current document mentions OBJ_* constants without their actual
values. A git developer would know these are from cache.h but that's
not very friendly to a person who wants to read this file to implement
a pack file parser.

Similarly, the deltified representation is not documented at all (the
"document" is basically patch-delta.c). Translate that C code to
English with a bit more about what ofs-delta and ref-delta mean.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-13 10:20:03 +09:00
Stefan Beller
dd5d9deb01 alloc: add repository argument to alloc_commit_index
This is a small mechanical change; it doesn't change the
implementation to handle repositories other than the_repository yet.
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>
2018-05-09 12:12:36 +09:00
Stefan Beller
17bfe87369 alloc: add repository argument to alloc_report
This is a small mechanical change; it doesn't change the
implementation to handle repositories other than the_repository yet.
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>
2018-05-09 12:12:36 +09:00
Stefan Beller
13e3fdcb76 alloc: add repository argument to alloc_object_node
This is a small mechanical change; it doesn't change the
implementation to handle repositories other than the_repository yet.
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>
2018-05-09 12:12:36 +09:00
Stefan Beller
a0bd9086bb alloc: add repository argument to alloc_tag_node
This is a small mechanical change; it doesn't change the
implementation to handle repositories other than the_repository yet.
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>
2018-05-09 12:12:36 +09:00
Stefan Beller
8ba0e5ec57 alloc: add repository argument to alloc_commit_node
This is a small mechanical change; it doesn't change the
implementation to handle repositories other than the_repository yet.
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>
2018-05-09 12:12:36 +09:00
Stefan Beller
cf7203bdc6 alloc: add repository argument to alloc_tree_node
This is a small mechanical change; it doesn't change the
implementation to handle repositories other than the_repository yet.
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>
2018-05-09 12:12:36 +09:00
Stefan Beller
f0de1d62ae alloc: add repository argument to alloc_blob_node
This is a small mechanical change; it doesn't change the
implementation to handle repositories other than the_repository yet.
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>
2018-05-09 12:12:36 +09:00
Junio C Hamano
174774cd51 Merge branch 'sb/object-store-replace'
The effort to pass the repository in-core structure throughout the
API continues.  This round deals with the code that implements the
refs/replace/ mechanism.

* sb/object-store-replace:
  replace-object: allow lookup_replace_object to handle arbitrary repositories
  replace-object: allow do_lookup_replace_object to handle arbitrary repositories
  replace-object: allow prepare_replace_object to handle arbitrary repositories
  refs: allow for_each_replace_ref to handle arbitrary repositories
  refs: store the main ref store inside the repository struct
  replace-object: add repository argument to lookup_replace_object
  replace-object: add repository argument to do_lookup_replace_object
  replace-object: add repository argument to prepare_replace_object
  refs: add repository argument to for_each_replace_ref
  refs: add repository argument to get_main_ref_store
  replace-object: check_replace_refs is safe in multi repo environment
  replace-object: eliminate replace objects prepared flag
  object-store: move lookup_replace_object to replace-object.h
  replace-object: move replace_map to object store
  replace_object: use oidmap
2018-05-08 15:59:21 +09:00
Junio C Hamano
b10edb2df5 Merge branch 'ds/commit-graph'
Precompute and store information necessary for ancestry traversal
in a separate file to optimize graph walking.

* ds/commit-graph:
  commit-graph: implement "--append" option
  commit-graph: build graph from starting commits
  commit-graph: read only from specific pack-indexes
  commit: integrate commit graph with commit parsing
  commit-graph: close under reachability
  commit-graph: add core.commitGraph setting
  commit-graph: implement git commit-graph read
  commit-graph: implement git-commit-graph write
  commit-graph: implement write_commit_graph()
  commit-graph: create git-commit-graph builtin
  graph: add commit graph design document
  commit-graph: add format document
  csum-file: refactor finalize_hashfile() method
  csum-file: rename hashclose() to finalize_hashfile()
2018-05-08 15:59:20 +09:00
Junio C Hamano
92034a9cd5 Merge branch 'dj/runtime-prefix'
A build-time option has been added to allow Git to be told to refer
to its associated files relative to the main binary, in the same
way that has been possible on Windows for quite some time, for
Linux, BSDs and Darwin.

* dj/runtime-prefix:
  Makefile: quote $INSTLIBDIR when passing it to sed
  Makefile: remove unused @@PERLLIBDIR@@ substitution variable
  mingw/msvc: use the new-style RUNTIME_PREFIX helper
  exec_cmd: provide a new-style RUNTIME_PREFIX helper for Windows
  exec_cmd: RUNTIME_PREFIX on some POSIX systems
  Makefile: add Perl runtime prefix support
  Makefile: generate Perl header from template file
2018-05-08 15:59:17 +09:00
brian m. carlson
e1ccd7e2b1 sha1_file: only expose empty object constants through git_hash_algo
There really isn't any case in which we want to expose the constants for
empty trees and blobs outside of using the hash algorithm abstraction.
Make these constants static and stop exposing the defines in cache.h.
Remove the constants which are no longer in use.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-02 13:59:53 +09:00
brian m. carlson
d8a92ced62 sha1-file: add functions for hex empty tree and blob OIDs
Oftentimes, we'll want to refer to an empty tree or empty blob by its
hex name without having to call oid_to_hex or explicitly refer to
the_hash_algo.  Add helper functions that format these values into
static buffers and return them for easy use.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-02 13:59:51 +09:00