A single-word "unsigned flags" in the diff options is being split
into a structure with many bitfields.
* bw/diff-opt-impl-to-bitfields:
diff: make struct diff_flags members lowercase
diff: remove DIFF_OPT_CLR macro
diff: remove DIFF_OPT_SET macro
diff: remove DIFF_OPT_TST macro
diff: remove touched flags
diff: add flag to indicate textconv was set via cmdline
diff: convert flags to be stored in bitfields
add, reset: use DIFF_OPT_SET macro to set a diff flag
Pathspec-limited revision traversal was taught not to keep finding
unneeded differences once it knows two trees are different inside
given pathspec.
* jk/revision-pruning-optim:
revision: quit pruning diff more quickly when possible
Remove the `DIFF_OPT_CLR` macro and instead set the flags directly.
This conversion is done using the following semantic patch:
@@
expression E;
identifier fld;
@@
- DIFF_OPT_CLR(&E, fld)
+ E.flags.fld = 0
@@
type T;
T *ptr;
identifier fld;
@@
- DIFF_OPT_CLR(ptr, fld)
+ ptr->flags.fld = 0
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remove the `DIFF_OPT_SET` macro and instead set the flags directly.
This conversion is done using the following semantic patch:
@@
expression E;
identifier fld;
@@
- DIFF_OPT_SET(&E, fld)
+ E.flags.fld = 1
@@
type T;
T *ptr;
identifier fld;
@@
- DIFF_OPT_SET(ptr, fld)
+ ptr->flags.fld = 1
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remove the `DIFF_OPT_TST` macro and instead access the flags directly.
This conversion is done using the following semantic patch:
@@
expression E;
identifier fld;
@@
- DIFF_OPT_TST(&E, fld)
+ E.flags.fld
@@
type T;
T *ptr;
identifier fld;
@@
- DIFF_OPT_TST(ptr, fld)
+ ptr->flags.fld
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the revision traversal machinery is given a pathspec,
we must compute the parent-diff for each commit to determine
which ones are TREESAME. We set the QUICK diff flag to avoid
looking at more entries than we need; we really just care
whether there are any changes at all.
But there is one case where we want to know a bit more: if
--remove-empty is set, we care about finding cases where the
change consists only of added entries (in which case we may
prune the parent in try_to_simplify_commit()). To cover that
case, our file_add_remove() callback does not quit the diff
upon seeing an added entry; it keeps looking for other types
of entries.
But this means when --remove-empty is not set (and it is not
by default), we compute more of the diff than is necessary.
You can see this in a pathological case where a commit adds
a very large number of entries, and we limit based on a
broad pathspec. E.g.:
perl -e '
chomp(my $blob = `git hash-object -w --stdin </dev/null`);
for my $a (1..1000) {
for my $b (1..1000) {
print "100644 $blob\t$a/$b\n";
}
}
' | git update-index --index-info
git commit -qm add
git rev-list HEAD -- .
This case takes about 100ms now, but after this patch only
needs 6ms. That's not a huge improvement, but it's easy to
get and it protects us against even more pathological cases
(e.g., going from 1 million to 10 million files would take
ten times as long with the current code, but not increase at
all after this patch).
This is reported to minorly speed-up pathspec limiting in
real world repositories (like the 100-million-file Windows
repository), but probably won't make a noticeable difference
outside of pathological setups.
This patch actually covers the case without --remove-empty,
and the case where we see only deletions. See the in-code
comment for details.
Note that we have to add a new member to the diff_options
struct so that our callback can see the value of
revs->remove_empty_trees. This callback parameter could be
passed to the "add_remove" and "change" callbacks, but
there's not much point. They already receive the
diff_options struct, and doing it this way avoids having to
update the function signature of the other callbacks
(arguably the format_callback and output_prefix functions
could benefit from the same simplification).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Code clean-up.
* rs/resolve-ref-optional-result:
refs: pass NULL to resolve_ref_unsafe() if hash is not needed
refs: pass NULL to refs_resolve_ref_unsafe() if hash is not needed
refs: make sha1 output parameter of refs_resolve_ref_unsafe() optional
This allows us to get rid of some write-only variables, among them seven
SHA1 buffers.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We assemble an array of strings in a custom struct,
NULL-terminate the result, and then pass it to
parse_pathspec().
But then we never free the array or the individual strings
(nor can we do the latter, as they are heap-allocated when
they come from stdin but not when they come from the
passed-in argv).
Let's swap this out for an argv_array. It does the same
thing with fewer lines of code, and it's safe to call
argv_array_clear() at the end to avoid a memory leak.
Reported-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git gc" and friends when multiple worktrees are used off of a
single repository did not consider the index and per-worktree refs
of other worktrees as the root for reachability traversal, making
objects that are in use only in other worktrees to be subject to
garbage collection.
* nd/prune-in-worktree:
refs.c: reindent get_submodule_ref_store()
refs.c: remove fallback-to-main-store code get_submodule_ref_store()
rev-list: expose and document --single-worktree
revision.c: --reflog add HEAD reflog from all worktrees
files-backend: make reflog iterator go through per-worktree reflog
revision.c: --all adds HEAD from all worktrees
refs: remove dead for_each_*_submodule()
refs.c: move for_each_remote_ref_submodule() to submodule.c
revision.c: use refs_for_each*() instead of for_each_*_submodule()
refs: add refs_head_ref()
refs: move submodule slash stripping code to get_submodule_ref_store
refs.c: refactor get_submodule_ref_store(), share common free block
revision.c: --indexed-objects add objects from all worktrees
revision.c: refactor add_index_objects_to_pending()
refs.c: use is_dir_sep() in resolve_gitlink_ref()
revision.h: new flag in struct rev_info wrt. worktree-related refs
"git log --tag=no-such-tag" showed log starting from HEAD, which
has been fixed---it now shows nothing.
* jk/rev-list-empty-input:
revision: do not fallback to default when rev_input_given is set
rev-list: don't show usage when we see empty ref patterns
revision: add rev_input_given flag
t6018: flesh out empty input/output rev-list tests
Note that add_other_reflogs_to_pending() is a bit inefficient, since
it scans reflog for all refs of each worktree, including shared refs,
so the shared ref's reflog is scanned over and over again.
We could update refs API to pass "per-worktree only" flag to avoid
that. But long term we should be able to obtain a "per-worktree only"
ref store and would need to revert the changes in reflog iteration
API. So let's just wait until then.
add_reflogs_to_pending() is called by reachable.c so by default "git
prune" will examine reflog from all worktrees.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Unless single_worktree is set, --all now adds HEAD from all worktrees.
Since reachable.c code does not use setup_revisions(), we need to call
other_head_refs_submodule() explicitly there to have the same effect on
"git prune", so that we won't accidentally delete objects needed by some
other HEADs.
A new FIXME is added because we would need something like
int refs_other_head_refs(struct ref_store *, each_ref_fn, cb_data);
in addition to other_head_refs() to handle it, which might require
int get_submodule_worktrees(const char *submodule, int flags);
It could be a separate topic to reduce the scope of this one.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is the result of single_worktree flag never being set (no way to up
until now). To get objects from current index only, set single_worktree.
The other add_index_objects_to_pending's caller is mark_reachable_objects()
(e.g. "git prune") which also mark objects from all indexes.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The core code is factored out and take 'struct index_state *' instead so
that we can reuse it to add objects from index files other than .git/index
in the next patch.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Numerous bugs in walking of reflogs via "log -g" and friends have
been fixed.
* jk/reflog-walk:
reflog-walk: apply --since/--until to reflog dates
reflog-walk: stop using fake parents
rev-list: check reflog_info before showing usage
get_revision_1(): replace do-while with an early return
log: do not free parents when walking reflog
log: clarify comment about reflog cycles
revision: disallow reflog walking with revs->limited
t1414: document some reflog-walk oddities
"git log --tag=no-such-tag" showed log starting from HEAD, which
has been fixed---it now shows nothing.
* jk/rev-list-empty-input:
revision: do not fallback to default when rev_input_given is set
rev-list: don't show usage when we see empty ref patterns
revision: add rev_input_given flag
t6018: flesh out empty input/output rev-list tests
Numerous bugs in walking of reflogs via "log -g" and friends have
been fixed.
* jk/reflog-walk:
reflog-walk: apply --since/--until to reflog dates
reflog-walk: stop using fake parents
rev-list: check reflog_info before showing usage
get_revision_1(): replace do-while with an early return
log: do not free parents when walking reflog
log: clarify comment about reflog cycles
revision: disallow reflog walking with revs->limited
t1414: document some reflog-walk oddities
Conversion from uchar[20] to struct object_id continues.
* bc/object-id:
sha1_name: convert uses of 40 to GIT_SHA1_HEXSZ
sha1_name: convert GET_SHA1* flags to GET_OID*
sha1_name: convert get_sha1* to get_oid*
Convert remaining callers of get_sha1 to get_oid.
builtin/unpack-file: convert to struct object_id
bisect: convert bisect_checkout to struct object_id
builtin/update_ref: convert to struct object_id
sequencer: convert to struct object_id
remote: convert struct push_cas to struct object_id
submodule: convert submodule config lookup to use object_id
builtin/merge-tree: convert remaining caller of get_sha1 to object_id
builtin/fsck: convert remaining caller of get_sha1 to object_id
If revs->def is set (as it is in "git log") and there are no
pending objects after parsing the user's input, then we show
whatever is in "def". But if the user _did_ ask for some
input that just happened to be empty (e.g., "--glob" that
does not match anything), showing the default revision is
confusing. We should just show nothing, as that is what the
user's request yielded.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Normally a caller that invokes setup_revisions() has to
check rev.pending to see if anything was actually queued for
the traversal. But they can't tell the difference between
two cases:
1. The user gave us no tip from which to start a
traversal.
2. The user tried to give us tips via --glob, --all, etc,
but their patterns ended up being empty.
Let's set a flag in the rev_info struct that callers can use
to tell the difference. We can set this from the
init_all_refs_cb() function. That's a little funny because
it's not exactly about initializing the "cb" struct itself.
But that function is the common setup place for doing
pattern traversals that is used by --glob, --all, etc.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Convert the flags for get_oid_with_context and friends to use "OID"
instead of "SHA1" in their names.
This transform was made by running the following one-liner on the
affected files:
perl -pi -e 's/GET_SHA1/GET_OID/g'
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Code cleanup.
* ab/grep-lose-opt-regflags:
grep: remove redundant REG_NEWLINE when compiling fixed regex
grep: remove regflags from the public grep_opt API
grep: remove redundant and verbose re-assignments to 0
grep: remove redundant "fixed" field re-assignment to 0
grep: adjust a redundant grep pattern type assignment
grep: remove redundant double assignment to 0
When doing a reflog walk, we use the commit's date to
do any date limiting. In earlier versions of Git, this could
lead to nonsense results, since a skipped commit would
truncate the traversal. So a sequence like:
git commit ...
git checkout week-old-branch
git checkout -
git log -g --since=1.day.ago
would stop at the week-old-branch, even though the "git
commit" entry further back is still interesting.
As of the prior commit, which uses a parent-less traversal
of the reflog, you get the whole reflog minus any commits
whose dates do not match the specified options. This is
arguably useful, as you could scan the reflogs for commits
that originated in a certain range.
But more likely a user doing a reflog walk wants to limit
based on the reflog entries themselves. You can simulate
--until with:
git log -g @{1.day.ago}
but there's no way to ask Git to traverse only back to a
certain date. E.g.:
# show me reflog entries from the past day
git log -g --since=1.day.ago
This patch teaches the revision machinery to prefer the
reflog entry dates to the commit dates when doing a reflog
walk. Technically this is a change in behavior that affects
plumbing, but the previous behavior was so buggy that it's
unlikely anyone was relying on it.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The reflog-walk system works by putting a ref's tip into the
pending queue, and then "traversing" the reflog by
pretending that the parent of each commit is the previous
reflog entry.
This causes a number of user-visible oddities, as documented
in t1414 (and the commit message which introduced it). We
can fix all of them in one go by replacing the fake-reflog
system with a much simpler one: just keeping a list of
reflogs to show, and walking through them entry by entry.
The implementation is fairly straight-forward, but there are
a few items to note:
1. We obviously must skip calling add_parents_to_list()
when we are traversing reflogs, since we do not want to
walk the original parents at all. As a result, we must call
try_to_simplify_commit() ourselves.
There are other parts of add_parents_to_list() we skip,
as well, but none of them should matter for a reflog
traversal:
- We do not allow UNINTERESTING commits, nor
symmetric ranges (and we bail when these are used
with "-g").
- Using --source makes no sense, since we aren't
traversing. The reflog selector shows the same
information with more detail.
- Using --first-parent is still sensible, since you
may want to see the first-parent diff for each
entry. But since we're not traversing, we don't
need to cull the parent list here.
2. Since we now just walk the reflog entries themselves,
rather than starting with the ref tip, we now look at
the "new" field of each entry rather than the "old"
(i.e., we are showing entries, not faking parents).
This removes all of the tricky logic around skipping
past root commits.
But note that we have no way to show an entry with the
null sha1 in its "new" field (because such a commit
obviously does not exist). Normally this would not
happen, since we delete reflogs along with refs, but
there is one special case. When we rename the currently
checked out branch, we write two reflog entries into
the HEAD log: one where the commit goes away, and
another where it comes back.
Prior to this commit, we show both entries with
identical reflog messages. After this commit, we show
only the "comes back" entry. See the update in t3200
which demonstrates this.
Arguably either is fine, as the whole double-entry
thing is a bit hacky in the first place. And until a
recent fix, we truncated the traversal in such a case
anyway, which was _definitely_ wrong.
3. We show individual reflogs in order, but choose which
reflog to show at each stage based on which has the
most recent timestamp. This interleaves the output
from multiple reflogs based on date order, which is
probably what you'd want with limiting like "-n 30".
Note that the implementation aims for simplicity. It
does a linear walk over the reflog queue for each
commit it pulls, which may perform badly if you
interleave an enormous number of reflogs. That seems
like an unlikely use case; if we did want to handle it,
we could probably keep a priority queue of reflogs,
ordered by the timestamp of their current tip entry.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The get_revision_1() function tries to avoid entering its
main loop at all when there are no commits to look at. But
it's perfectly safe to call pop_commit() on an empty list
(in which case it will return NULL). Switching to an early
return from the loop lets us skip repeating the loop
condition before we enter the do-while. That will get more
important when we start pulling reflog-walk commits from a
source besides the revs->commits queue, as that condition
will get much more complicated.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The reflog-walk code doesn't work with limit_list(). That
function traverses down the real history graph, not the fake
reflog history that get_revision() returns. So it's not
going to actually examine all of the commits we're going to
show, because we'd add them to the pending list only during
the actual traversal.
In practice this limitation doesn't really matter, because
the options that require list-limiting generally need
UNINTERESTING endpoints or symmetric ranges, which already
are forbidden for reflog walks. Still, there are likely some
corner cases that would behave oddly. We're better off to
warn the user that we can't fulfill their request than to
generate potentially wrong output.
This will also make it easier to refactor the reflog-walking
code, because it eliminates a whole area of corner cases
we'd have to consider (that already don't work anyway).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Refactor calls to the grep machinery to always pass opt.ignore_case &
opt.extended_regexp_option instead of setting the equivalent regflags
bits.
The bug fixed when making -i work with -P in commit 9e3cbc59d5 ("log:
make --regexp-ignore-case work with --perl-regexp", 2017-05-20) was
really just plastering over the code smell which this change fixes.
The reason for adding the extensive commentary here is that I
discovered some subtle complexity in implementing this that really
should be called out explicitly to future readers.
Before this change we'd rely on the difference between
`extended_regexp_option` and `regflags` to serve as a membrane between
our preliminary parsing of grep.extendedRegexp and grep.patternType,
and what we decided to do internally.
Now that those two are the same thing, it's necessary to unset
`extended_regexp_option` just before we commit in cases where both of
those config variables are set. See 84befcd0a4 ("grep: add a
grep.patternType configuration setting", 2012-08-03) for the code and
documentation related to that.
The explanation of why the if/else branches in
grep_commit_pattern_type() are ordered the way they are exists in that
commit message, but I think it's worth calling this subtlety out
explicitly with a comment for future readers.
Even though grep_commit_pattern_type() is the only caller of
grep_set_pattern_type_option() it's simpler to reset the
extended_regexp_option flag in the latter, since 2/3 branches in the
former would otherwise need to reset it, this way we can do it in one
place.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Bugfix for a topic that is (only) in 'master'.
* mh/packed-ref-store-prep:
for_each_bisect_ref(): don't trim refnames
lock_packed_refs(): fix cache validity check
Remove the unused wildopts placeholder struct from being passed to all
wildmatch() invocations, or rather remove all the boilerplate NULL
parameters.
This parameter was added back in commit 9b3497cab9 ("wildmatch: rename
constants and update prototype", 2013-01-01) as a placeholder for
future use. Over 4 years later nothing has made use of it, let's just
remove it. It can be added in the future if we find some reason to
start using such a parameter.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Code clean-up.
* sg/revision-parser-skip-prefix:
revision.c: use skip_prefix() in handle_revision_pseudo_opt()
revision.c: use skip_prefix() in handle_revision_opt()
revision.c: stricter parsing of '--early-output'
revision.c: stricter parsing of '--no-{min,max}-parents'
revision.h: turn rev_info.early_output back into an unsigned int
Update "perl-compatible regular expression" support to enable JIT
and also allow linking with the newer PCRE v2 library.
* ab/pcre-v2:
grep: add support for PCRE v2
grep: un-break building with PCRE >= 8.32 without --enable-jit
grep: un-break building with PCRE < 8.20
grep: un-break building with PCRE < 8.32
grep: add support for the PCRE v1 JIT API
log: add -P as a synonym for --perl-regexp
grep: skip pthreads overhead when using one thread
grep: don't redundantly compile throwaway patterns under threading
`for_each_bisect_ref()` is called by `for_each_bad_bisect_ref()` with
a term "bad". This used to make it call `for_each_ref_in_submodule()`
with a prefix "refs/bisect/bad". But the latter is the name of the
reference that is being sought, so the empty string was being passed
to the callback as the trimmed refname. Moreover, this questionable
practice was turned into an error by
b9c8e7f2fb prefix_ref_iterator: don't trim too much, 2017-05-22
It makes more sense (and agrees better with the documentation of
`--bisect`) for the callers to receive the full reference names. So
* Add a new function, `for_each_fullref_in_submodule()`, to the refs
API. This plugs a gap in the existing functionality, analogous to
`for_each_fullref_in()` but accepting a `submodule` argument.
* Change `for_each_bad_bisect_ref()` to call the new function rather
than `for_each_ref_in_submodule()`.
* Add a test.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of starts_with() and a bunch of magic numbers.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of starts_with() and a bunch of magic numbers.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The parsing of '--early-output' with or without its optional integer
argument allowed bogus options like '--early-output-foobarbaz' to slip
through and be ignored.
Fix it by parsing '--early-output' in the same way as other options
with an optional argument are parsed. Furthermore, use strtoul_ui()
to parse the optional integer argument and to refuse negative numbers.
While at it, use skip_prefix() instead of starts_with() and magic
numbers.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These two options are parsed using starts_with(), allowing things like
'git log --no-min-parents-foobarbaz' to succeed.
Use strcmp() instead.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The internal implementation of "git grep" has seen some clean-up.
* ab/grep-preparatory-cleanup: (31 commits)
grep: assert that threading is enabled when calling grep_{lock,unlock}
grep: given --threads with NO_PTHREADS=YesPlease, warn
pack-objects: fix buggy warning about threads
pack-objects & index-pack: add test for --threads warning
test-lib: add a PTHREADS prerequisite
grep: move is_fixed() earlier to avoid forward declaration
grep: change internal *pcre* variable & function names to be *pcre1*
grep: change the internal PCRE macro names to be PCRE1
grep: factor test for \0 in grep patterns into a function
grep: remove redundant regflags assignments
grep: catch a missing enum in switch statement
perf: add a comparison test of log --grep regex engines with -F
perf: add a comparison test of log --grep regex engines
perf: add a comparison test of grep regex engines with -F
perf: add a comparison test of grep regex engines
perf: emit progress output when unpacking & building
perf: add a GIT_PERF_MAKE_COMMAND for when *_MAKE_OPTS won't do
grep: add tests to fix blind spots with \0 patterns
grep: prepare for testing binary regexes containing rx metacharacters
grep: add a test helper function for less verbose -f \0 tests
...
The result from "git diff" that compares two blobs, e.g. "git diff
$commit1:$path $commit2:$path", used to be shown with the full
object name as given on the command line, but it is more natural to
use the $path in the output and use it to look up .gitattributes.
* jk/diff-blob:
diff: use blob path for blob/file diffs
diff: use pending "path" if it is available
diff: use the word "path" instead of "name" for blobs
diff: pass whole pending entry in blobinfo
handle_revision_arg: record paths for pending objects
handle_revision_arg: record modes for "a..b" endpoints
t4063: add tests of direct blob diffs
get_sha1_with_context: dynamically allocate oc->path
get_sha1_with_context: always initialize oc->symlink_path
sha1_name: consistently refer to object_context as "oc"
handle_revision_arg: add handle_dotdot() helper
handle_revision_arg: hoist ".." check out of range parsing
handle_revision_arg: stop using "dotdot" as a generic pointer
handle_revision_arg: simplify commit reference lookups
handle_revision_arg: reset "dotdot" consistently
Convert diff_change to take a struct object_id. In addition convert the
function pointer type 'change_fn_t' to also take a struct object_id.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>