Eliminate a theoretical risk of integer overflow if the two types have
different sizes.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

It will soon have some other users.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

In the future, compound reference stores will sometimes need to modify
references in two different reference stores at the same time, meaning
that a single logical reference transaction might have to be
implemented as two internal sub-transactions. They won't want to call
`ref_transaction_commit()` for the two sub-transactions one after the
other, because that wouldn't be atomic (the first commit could succeed
and the second one fail). Instead, they will want to prepare both
sub-transactions (i.e., obtain any necessary locks and do any
pre-checks), and only if both prepare steps succeed, then commit both
sub-transactions.

Start preparing for that day by adding a new, optional
`ref_transaction_prepare()` step to the reference transaction
sequence, which obtains the locks and does any prechecks, reporting
any errors that occur. Also add a `ref_transaction_abort()` function
that can be used to abort a sub-transaction even if it has already
been prepared.

That is on the side of the public-facing API. On the side of the
`ref_store` VTABLE, get rid of `transaction_commit` and instead add
methods `transaction_prepare`, `transaction_finish`, and
`transaction_abort`. A `ref_transaction_commit()` now basically calls
methods `transaction_prepare` then `transaction_finish`.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Move the check that `transaction->state` is valid from
`files_transaction_commit()` to `ref_transaction_commit()`, where
other future reference backends can benefit from it as well.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Extract the cleanup functionality from `files_transaction_commit()`
into a new function. It will soon have another caller.

Use the common cleanup code even on early exit if the transaction is
empty, to reduce code duplication.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Instead of using a global `lock_file` instance for the main
"packed-refs" file and using a pointer in `files_ref_store` to keep
track of whether it is locked, embed the `lock_file` instance directly
in the `files_ref_store` struct and use the new
`is_lock_file_locked()` function to keep track of whether it is
locked. This keeps related data together and makes the main reference
store less of a special case.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Move the `lock` member from `packed_ref_cache` to `files_ref_store`,
since at most one cache can have a locked "packed-refs" file
associated with it. Rename it to `packed_refs_lock` to make its
purpose clearer in its new home. More changes are coming here shortly.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

It will soon prove useful.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Just because the files backend can't retain reflogs for deleted
references is no reason that they shouldn't be supported by the
virtual method interface. Also, `delete_ref()` and `refs_delete_ref()`
have already gained `msg` parameters. Now let's add them to
`delete_refs()` and `refs_delete_refs()`.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Eliminate any chance of integer overflow on platforms where the two
types have different sizes.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The backend already correctly restricts its output to references whose
names start with the prefix. By passing the prefix again to
`prefix_ref_iterator`, we were forcing that iterator to do redundant
prefix comparisons. So set it to the empty string.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The `trim` parameter can be set independently of `prefix`. So if some
caller were to set `trim` to be greater than `strlen(prefix)`, we
could end up pointing the `refname` field of the iterator past the NUL
of the actual reference name string.

That can't happen currently, because `trim` is always set either to
zero or to `strlen(prefix)`. But even the latter could lead to
confusion, if a refname is exactly equal to the prefix, because then
we would set the outgoing `refname` to the empty string.

And we're about to decouple the `prefix` and `trim` arguments even
more, so let's be cautious here. Report a bug if ever asked to trim a
reference whose name is not longer than `trim`.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The former is by far more common in our codebase.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The iterator returned by this function only includes references whose
names start with the whole prefix, not all of those in
`find_containing_dir(prefix)` as the old docstring claimed. This
docstring was probably copy-pasted from old ref-cache code, which had
the old specification. But now, `cache_ref_iterator_begin()`
(from which the files reference iterator gets its values)
automatically wraps its output using `prefix_ref_iterator_begin()`
when necessary, so it has the stricter behavior.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

In particular, make it clear that they make copies of the sha1
arguments.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The test of failing `git rm -f` removes the write permissions on the
test directory, but fails to restore them if the test fails. This
means that the test temporary directory cannot be cleaned up, which
means that subsequent attempts to run the test fail mysteriously.

Instead, do the cleanup in a `test_when_finished` block so that it
can't be skipped.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

* bc/object-id: (53 commits)
  object: convert parse_object* to take struct object_id
  tree: convert parse_tree_indirect to struct object_id
  sequencer: convert do_recursive_merge to struct object_id
  diff-lib: convert do_diff_cache to struct object_id
  builtin/ls-tree: convert to struct object_id
  merge: convert checkout_fast_forward to struct object_id
  sequencer: convert fast_forward_to to struct object_id
  builtin/ls-files: convert overlay_tree_on_cache to object_id
  builtin/read-tree: convert to struct object_id
  sha1_name: convert internals of peel_onion to object_id
  upload-pack: convert remaining parse_object callers to object_id
  revision: convert remaining parse_object callers to object_id
  revision: rename add_pending_sha1 to add_pending_oid
  http-push: convert process_ls_object and descendants to object_id
  refs/files-backend: convert many internals to struct object_id
  refs: convert struct ref_update to use struct object_id
  ref-filter: convert some static functions to struct object_id
  Convert struct ref_array_item to struct object_id
  Convert the verify_pack callback to struct object_id
  Convert lookup_tag to struct object_id
  ...

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Update tests to pass under GETTEXT_POISON (a mechanism to ensure
that output strings that should not be translated are not
translated by mistake), and tell TravisCI to run them.

* ab/fix-poison-tests:
  travis-ci: add job to run tests with GETTEXT_POISON
  travis-ci: setup "prove cache" in "script" step
  tests: fix tests broken under GETTEXT_POISON=YesPlease

* tb/dedup-crlf-tests:
  t0027: tests are not expensive; remove t0025

The receive-pack program now makes sure that the push certificate
records the same set of push options used for pushing.

* jt/push-options-doc:
  receive-pack: verify push options in cert
  docs: correct receive.advertisePushOptions default

The Web interface to gmane news archive is long gone, even though
the articles are still accessible via NTTP.  Replace the links with
ones to public-inbox.org.  Because their message identification is
based on the actual message-id, it is likely that it will be easier
to migrate away from it if/when necessary.

* ab/doc-replace-gmane-links:
  doc: replace more gmane links
  doc: replace a couple of broken gmane links

A few codepaths in "checkout" and "am" working on an unborn branch
tried to access an uninitialized piece of memory.

* rs/checkout-am-fix-unborn:
  am: check return value of resolve_refdup before using hash
  checkout: check return value of resolve_refdup before using hash

* ls/travis-relays-for-windows-ci:
  travis-ci: retry if Git for Windows CI returns HTTP error 502 or 503
  travis-ci: handle Git for Windows CI status "failed" explicitly

Setting "log.decorate=false" in the configuration file did not take
effect in v2.13, which has been corrected.

* ah/log-decorate-default-to-auto:
  builtin/log: honor log.decorate

A hotfix to a topic that is already in v2.13.

* bw/submodule-with-bs-path:
  t7400: add !CYGWIN prerequisite to 'add with \\ in path'

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Some platforms have ulong that is smaller than time_t, and our
historical use of ulong for timestamp would mean they cannot
represent some timestamp that the platform allows.  Invent a
separate and dedicated timestamp_t (so that we can distingiuish
timestamps and a vanilla ulongs, which along is already a good
move), and then declare uintmax_t is the type to be used as the
timestamp_t.

* js/larger-timestamps:
  archive-tar: fix a sparse 'constant too large' warning
  use uintmax_t for timestamps
  date.c: abort if the system time cannot handle one of our timestamps
  timestamp_t: a new data type for timestamps
  PRItime: introduce a new "printf format" for timestamps
  parse_timestamp(): specify explicitly where we parse timestamps
  t0006 & t5000: skip "far in the future" test when time_t is too limited
  t0006 & t5000: prepare for 64-bit timestamps
  ref-filter: avoid using `unsigned long` for catch-all data type

* jc/apply-fix-mismerge:
  apply.c: fix whitespace-only mismerge

Build fix.

* ab/aix-needs-compat-regex:
  config.mak.uname: set NO_REGEX=NeedsStartEnd on AIX

Doc update.

* jn/credential-doc-on-clear:
  credential doc: make multiple-helper behavior more prominent

"git clone --config var=val" is a way to populate the
per-repository configuration file of the new repository, but it did
not work well when val is an empty string.  This has been fixed.

* jn/clone-add-empty-config-from-command-line:
  clone: handle empty config values in -c

Code clean-up and duplicate removal.

* bw/submodule-has-commits-update:
  submodule: refactor logic to determine changed submodules
  submodule: improve submodule_has_commits()
  submodule: change string_list changed_submodule_paths
  submodule: remove add_oid_to_argv()
  submodule: rename free_submodules_sha1s()
  submodule: rename add_sha1_to_array()

Travis CI gained a task to format the documentation with both
AsciiDoc and AsciiDoctor.

* ls/travis-doc-asciidoctor:
  travis-ci: check AsciiDoc/AsciiDoctor stderr output
  travis-ci: unset compiler for jobs that do not need one
  travis-ci: parallelize documentation build
  travis-ci: build documentation with AsciiDoc and Asciidoctor

"git archive --format=zip" learned to use zip64 extension when
necessary to go beyond the 4GB limit.

* rs/large-zip:
  t5004: require 64-bit support for big ZIP tests
  archive-zip: set version field for big files correctly
  archive-zip: support files bigger than 4GB
  archive-zip: support archives bigger than 4GB
  archive-zip: write ZIP dir entry directly to strbuf
  archive-zip: use strbuf for ZIP directory
  archive-zip: add tests for big ZIP archives

"git clone" learned the "--no-tags" option not to fetch all tags
initially, and also set up the tagopt not to follow any tags in
subsequent fetches.

* ab/clone-no-tags:
  tests: rename a test having to do with shallow submodules
  clone: add a --no-tags option to clone without tags
  tests: change "cd ... && git fetch" to "cd &&\n\tgit fetch"

The colors in which "git status --short --branch" showed the names
of the current branch and its remote-tracking branch are now
configurable.

* sk/status-short-branch-color-config:
  status: add color config slots for branch info in "--short --branch"
  status: fix missing newline when comment chars are disabled

The codepath in "git am" that is used when running "git rebase"
leaked memory held for the log message of the commits being rebased.

* jk/am-leakfix:
  am: shorten ident_split variable name in get_commit_info()
  am: simplify allocations in get_commit_info()
  am: fix commit buffer leak in get_commit_info()

"git cherry-pick" and other uses of the sequencer machinery
mishandled a trailer block whose last line is an incomplete line.
This has been fixed so that an additional sign-off etc. are added
after completing the existing incomplete line.

* jt/use-trailer-api-in-commands:
  sequencer: add newline before adding footers

"git gc" did not interact well with "git worktree"-managed
per-worktree refs.

* nd/worktree-kill-parse-ref:
  refs: kill set_worktree_head_symref()
  worktree.c: kill parse_ref() in favor of refs_resolve_ref_unsafe()
  refs: introduce get_worktree_ref_store()
  refs: add REFS_STORE_ALL_CAPS
  refs.c: make submodule ref store hashmap generic
  environment.c: fix potential segfault by get_git_common_dir()