Taylor Blau [Fri, 1 Oct 2021 22:38:10 +0000 (18:38 -0400)]
builtin/repack.c: pass `--refs-snapshot` when writing bitmaps
To prevent the race described in an earlier patch, generate and pass a
reference snapshot to the multi-pack bitmap code, if we are writing one
from `git repack`.
This patch is mostly limited to creating a temporary file, and then
calling for_each_ref(). Except we try to minimize duplicates, since
doing so can drastically reduce the size in network-of-forks style
repositories. In the kernel's fork network (the repository containing
all objects from the kernel and all its forks), deduplicating the
references drops the snapshot size from 934 MB to just 12 MB.
But since we're handling duplicates in this way, we have to make sure
that we preferred references (those listed in pack.preferBitmapTips)
before non-preferred ones (to avoid recording an object which is pointed
at by a preferred tip as non-preferred).
We accomplish this by doing separate passes over the references: first
visiting each prefix in pack.preferBitmapTips, and then over the rest of
the references.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Bagas Sanjaya [Fri, 1 Oct 2021 11:47:45 +0000 (18:47 +0700)]
bisect--helper: add space between colon and following sentence
Add missing space between colon sentence (`bisect-run failed:`) and the
following sentence (`git bisect--helper --bisect-state`).
Fixes: d1bbbe45df (bisect--helper: reimplement `bisect_run` shell
function in C, 2021-09-13) Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Bagas Sanjaya [Fri, 1 Oct 2021 11:37:25 +0000 (18:37 +0700)]
blame: describe default output format
While there is descriptions for porcelain and incremental output
formats, the default format isn't described. Describe that format for
the sake of completeness.
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Improve the error that's emitted in cases where we find a loose object
we parse, but which isn't at the location we expect it to be.
Before this change we'd prefix the error with a not-a-OID derived from
the path at which the object was found, due to an emergent behavior in
how we'd end up with an "OID" in these codepaths.
Now we'll instead say what object we hashed, and what path it was
found at. Before this patch series e.g.:
As noted in an earlier commits we'd simply die early in those cases,
until preceding commits fixed the hard die on invalid object type:
$ git fsck
fatal: invalid object type
Now we'll instead emit sensible error messages:
$ git fsck
error: 8315[...]: hash-path mismatch, found at: ./objects/84/15[...]
error: 8315[...]: object is of unknown type 'garbage': ./objects/84/15[...]
In both fsck.c and object-file.c we're using null_oid as a sentinel
value for checking whether we got far enough to be certain that the
issue was indeed this OID mismatch.
We need to add the "object corrupt or missing" special-case to deal
with cases where read_loose_object() will return an error before
completing check_object_signature(), e.g. if we have an error in
unpack_loose_rest() because we find garbage after the valid gzip
content:
There is currently some weird messaging in the edge case when the two
are combined, i.e. because we're not explicitly passing along an error
state about this specific scenario from check_stream_oid() via
read_loose_object() we'll end up printing the null OID if an object is
of an unknown type *and* it can't be unpacked by zlib, e.g.:
I think it's OK to leave that for future improvements, which would
involve enum-ifying more error state as we've done with "enum
unpack_loose_header_result" in preceding commits. In these
increasingly more obscure cases the worst that can happen is that
we'll get slightly nonsensical or inapplicable error messages.
There's other such potential edge cases, all of which might produce
some confusing messaging, but still be handled correctly as far as
passing along errors goes. E.g. if check_object_signature() returns
and oideq(real_oid, null_oid()) is true, which could happen if it
returns -1 due to the read_istream() call having failed.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
$ git fsck
error: <OID>: object is of unknown type 'garbage': <OID_PATH>
[ other fsck output ]
We'll still exit with non-zero, but now we'll finish the rest of the
traversal. The tests that's being added here asserts that we'll still
complain about other fsck issues (e.g. an unrelated dangling blob).
To do this we need to pass down the "OBJECT_INFO_ALLOW_UNKNOWN_TYPE"
flag from read_loose_object() through to parse_loose_header(). Since
the read_loose_object() function is only used in builtin/fsck.c we can
simply change it to accept a "struct object_info" (which contains the
OBJECT_INFO_ALLOW_UNKNOWN_TYPE in its flags). See f6371f92104 (sha1_file: add read_loose_object() function, 2017-01-13)
for the introduction of read_loose_object().
Since we'll need a "struct strbuf" to hold the "type_name" let's pass
it to the for_each_loose_file_in_objdir() callback to avoid allocating
a new one for each loose object in the iteration. It also makes the
memory management simpler than sticking it in fsck_loose() itself, as
we'll only need to strbuf_reset() it, with no need to do a
strbuf_release() before each "return".
Before this commit we'd never check the "type" if read_loose_object()
failed, but now we do. We therefore need to initialize it to OBJ_NONE
to be able to tell the difference between e.g. its
unpack_loose_header() having failed, and us getting past that and into
parse_loose_header().
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Make parse_loose_header() return error codes and data instead of
invoking die() by itself.
For now we'll move the relevant die() call to loose_object_info() and
read_loose_object() to keep this change smaller. In a subsequent
commit we'll make read_loose_object() return an error code instead of
dying. We should also address the "allow_unknown" case (should be
moved to builtin/cat-file.c), but for now I'll be leaving it.
For making parse_loose_header() not die() change its prototype to
accept a "struct object_info *" instead of the "unsigned long *sizep"
it accepted before. Its callers can now check the populated populated
"oi->typep".
Because of this we don't need to pass in the "unsigned int flags"
which we used for OBJECT_INFO_ALLOW_UNKNOWN_TYPE, we can instead do
that check in loose_object_info().
This also refactors some confusing control flow around the "status"
variable. In some cases we set it to the return value of "error()",
i.e. -1, and later checked if "status < 0" was true.
Since 93cff9a978e (sha1_loose_object_info: return error for corrupted
objects, 2017-04-01) the return value of loose_object_info() (then
named sha1_loose_object_info()) had been a "status" variable that be
any negative value, as we were expecting to return the "enum
object_type".
The only negative type happens to be OBJ_BAD, but the code still
assumed that more might be added. This was then used later in
e.g. c84a1f3ed4d (sha1_file: refactor read_object, 2017-06-21). Now
that parse_loose_header() will return 0 on success instead of the
type (which it'll stick into the "struct object_info") we don't need
to conflate these two cases in its callers.
Since parse_loose_header() doesn't need to return an arbitrary
"status" we only need to treat its "ret < 0" specially, but can
idiomatically overwrite it with our own error() return. This along
with having made unpack_loose_header() return an "enum
unpack_loose_header_result" in an earlier commit means that we can
move the previously nested if/else cases mostly into the "ULHR_OK"
branch of the "switch" statement.
We should be less silent if we reach that "status = -1" branch, which
happens if we've got trailing garbage in loose objects, see f6371f92104 (sha1_file: add read_loose_object() function, 2017-01-13)
for a better way to handle it. For now let's punt on it, a subsequent
commit will address that edge case.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-file.c: return ULHR_TOO_LONG on "header too long"
Split up the return code for "header too long" from the generic
negative return value unpack_loose_header() returns, and report via
error() if we exceed MAX_HEADER_LEN.
As a test added earlier in this series in t1006-cat-file.sh shows
we'll correctly emit zlib errors from zlib.c already in this case, so
we have no need to carry those return codes further down the
stack. Let's instead just return ULHR_TOO_LONG saying we ran into the
MAX_HEADER_LEN limit, or other negative values for "unable to unpack
<OID> header".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-file.c: use "enum" return type for unpack_loose_header()
In a preceding commit we changed and documented unpack_loose_header()
from its previous behavior of returning any negative value or zero, to
only -1 or 0.
Let's add an "enum unpack_loose_header_result" type and use it for
these return values, and have the compiler assert that we're
exhaustively covering all of them.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Combine the unpack_loose_short_header(),
unpack_loose_header_to_strbuf() and unpack_loose_header() functions
into one.
The unpack_loose_header_to_strbuf() function was added in 46f034483eb (sha1_file: support reading from a loose object of unknown
type, 2015-05-03).
Its code was mostly copy/pasted between it and both of
unpack_loose_header() and unpack_loose_short_header(). We now have a
single unpack_loose_header() function which accepts an optional
"struct strbuf *" instead.
I think the remaining unpack_loose_header() function could be further
simplified, we're carrying some complexity just to be able to emit a
garbage type longer than MAX_HEADER_LEN, we could alternatively just
say "we found a garbage type <first 32 bytes>..." instead. But let's
leave the current behavior in place for now.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-file.c: make parse_loose_header_extended() public
Make the parse_loose_header_extended() function public and remove the
parse_loose_header() wrapper. The only direct user of it outside of
object-file.c itself was in streaming.c, that caller can simply pass
the required "struct object-info *" instead.
This change is being done in preparation for teaching
read_loose_object() to accept a flag to pass to
parse_loose_header(). It isn't strictly necessary for that change, we
could simply use parse_loose_header_extended() there, but will leave
the API in a better end state.
It would be a better end-state to have already moved the declaration
of these functions to object-store.h to avoid the forward declaration
of "struct object_info" in cache.h, but let's leave that cleanup for
some other time.
object-file.c: return -1, not "status" from unpack_loose_header()
Return a -1 when git_inflate() fails instead of whatever Z_* status
we'd get from zlib.c. This makes no difference to any error we report,
but makes it more obvious that we don't care about the specific zlib
error codes here.
See d21f8426907 (unpack_sha1_header(): detect malformed object header,
2016-09-25) for the commit that added the "return status" code. As far
as I can tell there was never a real reason (e.g. different reporting)
for carrying down the "status" as opposed to "-1".
At the time that d21f8426907 was written there was a corresponding
"ret < Z_OK" check right after the unpack_sha1_header() call (the
"unpack_sha1_header()" function was later rename to our current
"unpack_loose_header()").
However, that check was removed in c84a1f3ed4d (sha1_file: refactor
read_object, 2017-06-21) without changing the corresponding return
code.
So let's do the minor cleanup of also changing this function to return
a -1.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-file.c: don't set "typep" when returning non-zero
When the loose_object_info() function returns an error stop faking up
the "oi->typep" to OBJ_BAD. Let the return value of the function
itself suffice. This code cleanup simplifies subsequent changes.
That we set this at all is a relic from the past. Before 052fe5eaca9 (sha1_loose_object_info: make type lookup optional,
2013-07-12) we would always return the type_from_string(type) via the
parse_sha1_header() function, or -1 (i.e. OBJ_BAD) if we couldn't
parse it.
Then in a combination of 46f034483eb (sha1_file: support reading from
a loose object of unknown type, 2015-05-03) and b3ea7dd32d6 (sha1_loose_object_info: handle errors from
unpack_sha1_rest, 2017-10-05) our API drifted even further towards
conflating the two again.
Having read the code paths involved carefully I think this is OK. We
are just about to return -1, and we have only one caller:
do_oid_object_info_extended(). That function will in turn go on to
return -1 when we return -1 here.
This might be introducing a subtle bug where a caller of
oid_object_info_extended() would inspect its "typep" and expect a
meaningful value if the function returned -1.
Such a problem would not occur for its simpler oid_object_info()
sister function. That one always returns the "enum object_type", which
in the case of -1 would be the OBJ_BAD.
Having read the code for all the callers of these functions I don't
believe any such bug is being introduced here, and in any case we'd
likely already have such a bug for the "sizep" member (although
blindly checking "typep" first would be a more common case).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
cat-file tests: test for current --allow-unknown-type behavior
Add more tests for the current --allow-unknown-type behavior. As noted
in [1] I don't think much of this makes sense, but let's test for it
as-is so we can see if the behavior changes in the future.
Fix a blindspot in the tests for "cat-file" (and by proxy, the guts of
object-file.c) by testing that when we can't decode a loose object
with zlib we'll emit an error from zlib.c.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
cat-file tests: test for missing/bogus object with -t, -s and -p
When we look up a missing object with cat_one_file() what error we
print out currently depends on whether we'll error out early in
get_oid_with_context(), or if we'll get an error later from
oid_object_info_extended().
The --allow-unknown-type flag then changes whether we pass the
"OBJECT_INFO_ALLOW_UNKNOWN_TYPE" flag to get_oid_with_context() or
not.
The "-p" flag is yet another special-case in printing the same output
on the deadbeef OID as we'd emit on the deadbeef_short OID for the
"-s" and "-t" options, it also doesn't support the
"--allow-unknown-type" flag at all.
Let's test the combination of the two sets of [-t, -s, -p] and
[--{no-}allow-unknown-type] (the --no-allow-unknown-type is implicit
in not supplying it), as well as a [missing,bogus] object pair.
This extends tests added in 3e370f9faf0 (t1006: add tests for git
cat-file --allow-unknown-type, 2015-05-03).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the short/long bogus bogus object type variables into a form
where the two sets can be used concurrently. This'll be used by
subsequently added tests.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
fsck tests: test current hash/type mismatch behavior
If fsck we move an object around between .git/objects/?? directories
to simulate a hash mismatch "git fsck" will currently hard die() in
object-file.c. This behavior will be fixed in subsequent commits, but
let's test for it as-is for now.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Refactor one of the fsck tests to use a throwaway repository. It's a
pervasive pattern in t1450-fsck.sh to spend a lot of effort on the
teardown of a tests so we're not leaving corrupt content for the next
test.
We can instead use the pattern of creating a named sub-repository,
then we don't have to worry about cleaning up after ourselves, nobody
will care what state the broken "hash-mismatch" repository is after
this test runs.
See [1] for related discussion on various "modern" test patterns that
can be used to avoid verbosity and increase reliability.
The init_log_tree_opt() and log_tree_opt_parse() functions were
removed in cd2bdc53094 (Common option parsing for "git log --diff" and
friends, 2006-04-14), but not their corresponding *.h declaration.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
This function was removed in 0579f91dd74 (grep: enable threading with
-p and -W using lazy attribute lookup, 2011-12-12), but not its
corresponding *.h declaration.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the preceding commit we introduced REF_STATES_INIT, but did not
change the "struct show_info" to have a corresponding
initializer. Let's do that, and make it use "REF_STATES_INIT" and
"STRING_LIST_INIT_DUP", doing that requires changing "list" and
"states" away from being pointers.
The resulting end-state is simpler since we omit the local "info_list"
and "states" variables in show() as well as the memset().
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use a new REF_STATES_INIT designated initializer instead of assigning
to the "strdup_strings" member of the previously memzero()'d version
of this struct.
The pattern of assigning to "strdup_strings" dates back to 211c89682ee (Make git-remote a builtin, 2008-02-29) (when it was
"strdup_paths"), i.e. long before we used anything like our current
established *_INIT patterns consistently.
Then in e61e0cc6b70 (builtin-remote: teach show to display remote
HEAD, 2009-02-25) and e5dcbfd9ab7 (builtin-remote: new show output
style for push refspecs, 2009-02-25) we added some more of these.
As it turns out we only initialized this struct three times, all the
other uses were of pointers to those initialized structs. So let's
initialize it in those three places, skip the memset(), and pass those
structs down appropriately.
This would be a behavior change if we had codepaths that relied say on
implicitly having had "new_refs" initialized to STRING_LIST_INIT_NODUP
with the memset(), but only set the "strdup_strings" on some other
struct, but then called string_list_append() on "new_refs". There
isn't any such codepath, all of the late assignments to
"strdup_strings" assigned to those structs that we'd use for those
codepaths.
So just initializing them all up-front makes for easier to understand
code, i.e. in the pre-image it looked as though we had that tricky
edge case, but we didn't.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the initialization pattern of "struct urlmatch_config" to use
an *_INIT macro and designated initializers. Right now there's no
other "struct" member of "struct urlmatch_config" which would require
its own *_INIT, but it's good practice not to assume that. Let's also
change this to a designated initializer while we're at it.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
René Scharfe [Fri, 1 Oct 2021 09:22:39 +0000 (11:22 +0200)]
mergesort: use ranks stack
The bottom-up mergesort implementation needs to skip through sublists a
lot. A recursive version could avoid that, but would require log2(n)
stack frames. Explicitly manage a stack of sorted sublists of various
lengths instead to avoid fast-forwarding while also keeping a lid on
memory usage.
While this patch was developed independently, a ranks stack is also used
in https://github.com/mono/mono/blob/master/mono/eglib/sort.frag.h by
the Mono project.
The idea is to keep slots for log2(n_max) sorted sublists, one for each
power of 2. Such a construct can accommodate lists of any length up to
n_max. Since there is a known maximum number of items (effectively
SIZE_MAX), we can preallocate the whole rank stack.
We add items one by one, which is akin to incrementing a binary number.
Make use of that by keeping track of the number of items and check bits
in it instead of checking for NULL in the rank stack when checking if a
sublist of a certain rank exists, in order to avoid memory accesses.
The first item can go into the empty first slot as a sublist of length
2^0. The second one needs to be merged with the previous sublist and
the result goes into the empty second slot as a sublist of length 2^1.
The third one goes into vacated first slot and so on. At the end we
merge all the sublists to get the result.
The new version still performs a stable sort by making sure to put items
seen earlier first when the compare function indicates equality. That's
done by preferring items from sublists with a higher rank.
The new merge function also tries to minimize the number of operations.
Like blame.c::blame_merge(), the function doesn't set the next pointer
if it already points to the right item, and it exits when it reaches the
end of one of the two sublists that it's given. The old code couldn't
do the latter because it kept all items in a single list.
The number of comparisons stays the same, though. Here's example output
of "test-tool mergesort test" for the rand distributions with the most
number of comparisons with the ranks stack:
$ t/helper/test-tool mergesort test | awk '
NR > 1 && $1 != "rand" {next}
$7 > max[$3] {max[$3] = $7; line[$3] = $0}
END {for (n in line) print line[n]}
'
distribut mode n m get_next set_next compare verdict
rand copy 100 32 669 420 569 OK
rand dither 1023 64 9997 5396 8974 OK
rand dither 1024 512 10007 6159 8983 OK
rand dither 1025 256 10993 5988 9968 OK
Here are the differences to the results without this patch:
The numbers of get_next and set_next calls are reduced significantly.
NB: These winners are different than the ones shown in the patch that
introduced the unriffle mode because the addition of the unriffle_skewed
mode in between changed the consumption of rand() values.
Here are the distributions with the most comparisons overall with the
ranks stack:
$ t/helper/test-tool mergesort test | awk '
$7 > max[$3] {max[$3] = $7; line[$3] = $0}
END {for (n in line) print line[n]}
'
distribut mode n m get_next set_next compare verdict
sawtooth unriffle_skewed 100 128 689 632 589 OK
sawtooth unriffle_skewed 1023 1024 10230 10220 9207 OK
sawtooth unriffle 1024 1024 10241 10240 9217 OK
sawtooth unriffle_skewed 1025 2048 11266 10242 10241 OK
René Scharfe [Fri, 1 Oct 2021 09:19:04 +0000 (11:19 +0200)]
p0071: measure sorting of already sorted and reversed files
Check if sorting takes advantage of already sorted or reversed content,
or if that corner case actually decreases performance, like it would for
a simplistic quicksort implementation.
Signed-off-by: René Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
René Scharfe [Fri, 1 Oct 2021 09:17:57 +0000 (11:17 +0200)]
test-mergesort: add unriffle_skewed mode
Add a mode that turns a sorted list into adversarial input for a
bottom-up mergesort implementation that doubles the length of sorted
sublists at each level -- like our llist_mergesort().
While unriffle mode splits the list in half at each recursion step,
unriffle_skewed splits it into 2^l items and the rest, with 2^l being
the highest power of two smaller than the number of items and thus
2^l >= rest. The rest is unriffled with the tail of the first half to
require a merge to compare the maximum number of elements.
It complements the unriffle mode, which targets balanced merges. If
the number of elements is a power of two then both actually produce the
same result, as 2^l == rest == n/2 at each recursion step in that case.
Here are the results:
$ t/helper/test-tool mergesort test | awk '
$7 > max[$3] {max[$3] = $7; line[$3] = $0}
END {for (n in line) print line[n]}
'
distribut mode n m get_next set_next compare verdict
sawtooth unriffle_skewed 100 128 1184 700 589 OK
sawtooth unriffle_skewed 1023 1024 16373 10230 9207 OK
sawtooth unriffle 1024 1024 16384 10240 9217 OK
sawtooth unriffle_skewed 1025 2048 18454 11275 10241 OK
The sawtooth distribution with m>=n produces a sorted list and
unriffle_skewed mode turns it into adversarial input for unbalanced
merges, which it wins in all cases except for n=1024 -- the resulting
list is the same, but unriffle is tested before unriffle_skewed, so its
result is selected by the AWK script.
Signed-off-by: René Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
René Scharfe [Fri, 1 Oct 2021 09:16:49 +0000 (11:16 +0200)]
test-mergesort: add unriffle mode
Add a mode that turns sorted items into adversarial input for mergesort.
Do that by running mergesort in reverse and rearranging the items in
such a way that each merge needs the maximum number of operations to
undo it.
To riffle is a card shuffling technique and involves splitting a deck
into two and then to interleave them. A perfect riffle takes one card
from each half in turn. That's similar to the most expensive merge,
which has to take one item from each sublist in turn, which requires the
maximum number of comparisons (n-1).
So unriffle does that in reverse, i.e. it generates the first sublist
out of the items at even indexes and the second sublist out of the items
at odd indexes, without changing their order in any other way. Done
recursively until we reach the trivial sublist length of one, this
twists the list into an order that requires the maximum effort for
mergesort to untangle.
As a baseline, here are the rand distributions with the highest number
of comparisons from "test-tool mergesort test":
$ t/helper/test-tool mergesort test | awk '
NR > 1 && $1 != "rand" {next}
$7 > max[$3] {max[$3] = $7; line[$3] = $0}
END {for (n in line) print line[n]}
'
distribut mode n m get_next set_next compare verdict
rand copy 100 32 1184 700 569 OK
rand reverse_1st_half 1023 256 16373 10230 8976 OK
rand reverse_1st_half 1024 512 16384 10240 8993 OK
rand dither 1025 64 18454 11275 9970 OK
And here are the most expensive ones overall:
$ t/helper/test-tool mergesort test | awk '
$7 > max[$3] {max[$3] = $7; line[$3] = $0}
END {for (n in line) print line[n]}
'
distribut mode n m get_next set_next compare verdict
stagger reverse 100 64 1184 700 580 OK
sawtooth unriffle 1023 1024 16373 10230 9179 OK
sawtooth unriffle 1024 1024 16384 10240 9217 OK
stagger unriffle 1025 2048 18454 11275 10241 OK
The sawtooth distribution with m>=n generates a sorted list. The
unriffle mode is designed to turn that into adversarial input for
mergesort, and that checks out for n=1023 and n=1024, where it produces
the list that requires the most comparisons.
Item counts that are not powers of two have other winners, and that's
because unriffle recursively splits lists into equal-sized halves, while
llist_mergesort() splits them into the biggest power of two smaller than
n and the rest, e.g. for n=1025 it sorts the first 1024 separately and
finally merges them to the last item.
So unriffle mode works as designed for the intended use case, but to
consistently generate adversarial input for unbalanced merges we need
something else.
Signed-off-by: René Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
René Scharfe [Fri, 1 Oct 2021 09:14:32 +0000 (11:14 +0200)]
test-mergesort: add generate subcommand
Add a subcommand for printing test data. It can be used to generate
special test cases and feed them into the sort subcommand or sort(1) for
performance measurements. It may also be useful to illustrate the
effect of distributions, modes and their parameters.
It generates n integers with the specified distribution and its
distribution-specific parameter m. E.g. m is the maximum value for
the plateau distribution and the length and height of individual teeth
of the sawtooth distribution.
The generated values are printed as zero-padded eight-digit hexadecimal
numbers to make sure alphabetic and numeric order are the same.
Signed-off-by: René Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
René Scharfe [Fri, 1 Oct 2021 09:12:27 +0000 (11:12 +0200)]
test-mergesort: add test subcommand
Adapt the qsort certification program from "Engineering a Sort Function"
by Bentley and McIlroy for testing our linked list sort function. It
generates several lists with various distribution patterns and counts
the number of operations llist_mergesort() needs to order them. It
compares the result to the output of a trusted sort function (qsort(1))
and also checks if the sort is stable.
Also add a test script that makes use of the new subcommand.
Signed-off-by: René Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
David Aguilar [Fri, 1 Oct 2021 01:37:55 +0000 (18:37 -0700)]
difftool: remove an unnecessary call to strbuf_release()
The `buf` strbuf is reused again later in the same function, so there
is no benefit to calling strbuf_release(). The subsequent usage is
already using strbuf_reset() to reset the buffer, so releasing it
early is only going to lead to a wasteful reallocation.
Remove the early call to strbuf_release(). The same strbuf is already
cleaned up in the "finish:" section so nothing is leaked, either.
Signed-off-by: David Aguilar <davvid@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
David Aguilar [Fri, 1 Oct 2021 01:37:54 +0000 (18:37 -0700)]
difftool: refactor dir-diff to write files using helper functions
Add a helpers function to handle the unlinking and writing
of the dir-diff submodule and symlink stand-in files.
Use the helpers to implement the guts of the hashmap loops.
This eliminate duplicate code and safeguards the submodules
hashmap loop against the symlink-chasing behavior that 5bafb3576a
(difftool: fix symlink-file writing in dir-diff mode, 2021-09-22)
addressed.
The submodules loop should not strictly require the unlink() call that
this is introducing to them, but it does not necessarily hurt them
either beyond the cost of the extra unlink().
Signed-off-by: David Aguilar <davvid@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
David Aguilar [Fri, 1 Oct 2021 01:37:53 +0000 (18:37 -0700)]
difftool: create a tmpdir path without repeated slashes
The paths generated by difftool are passed to user-facing diff tools.
Using paths with repeated slashes in them is a cosmetic blemish that
is exposed to users and can be avoided.
Use a strbuf to create the buffer used for the dir-diff tmpdir.
Strip trailing slashes from the value read from TMPDIR to avoid
repeated slashes in the generated paths.
Adjust the error handling to avoid leaking strbufs and to avoid
returning -1 to cmd_main().
Signed-off-by: David Aguilar <davvid@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Hamza Mahfooz [Wed, 29 Sep 2021 11:57:15 +0000 (07:57 -0400)]
grep: refactor next_match() and match_one_pattern() for external use
These changes are made in preparation of, the colorization support for the
"git log" subcommands that, rely on regex functionality (i.e. "--author",
"--committer" and "--grep"). These changes are necessary primarily because
match_one_pattern() expects header lines to be prefixed, however, in
pretty, the prefixes are stripped from the lines because the name-email
pairs need to go through additional parsing, before they can be printed and
because next_match() doesn't handle the case of
"ctx == GREP_CONTEXT_HEAD" at all. So, teach next_match() how to handle the
new case and move match_one_pattern()'s core logic to
headerless_match_one_pattern() while preserving match_one_pattern()'s uses
that depend on the additional processing.
Signed-off-by: Hamza Mahfooz <someguy@effective-light.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
grep: demonstrate bug with textconv attributes and submodules
In some circumstances, "git grep --textconv --recurse-submodules"
ignores the textconv attributes from the submodules and erroneously
applies the attributes defined in the superproject on the submodules'
files. The textconv cache is also saved on the superproject, even for
submodule objects.
A fix for these problems will probably require at least three changes:
- Some textconv and attributes functions (as well as their callees) will
have to be adjusted to work with arbitrary repositories. Note that
"fill_textconv()", for example, already receives a "struct repository"
but it writes the textconv cache using "write_loose_object()", which
implicitly works on "the_repository".
- grep.c functions will have to call textconv/userdiff routines passing
the "repo" field from "struct grep_source" instead of the one from
"struct grep_opt". The latter always points to "the_repository" on
"git grep" executions (see its initialization in builtin/grep.c), but
the former points to the correct repository that each source (an
object, file, or buffer) comes from.
- "userdiff_find_by_path()" might need to use a different attributes
stack for each repository it works on or reset its internal static
stack when the repository is changed throughout the calls.
For now, let's add some tests to demonstrate these problems, and also
update a NEEDSWORK comment in grep.h that mentions this bug to reference
the added tests.
Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 29 Sep 2021 01:55:20 +0000 (21:55 -0400)]
builtin/repack.c: make largest pack preferred
When repacking into a geometric series and writing a multi-pack bitmap,
it is beneficial to have the largest resulting pack be the preferred
object source in the bitmap's MIDX, since selecting the large packs can
lead to fewer broken delta chains and better compression.
Teach 'git repack' to identify this pack and pass it to the MIDX write
machinery in order to mark it as preferred.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 29 Sep 2021 01:55:18 +0000 (21:55 -0400)]
builtin/repack.c: support writing a MIDX while repacking
Teach `git repack` a new `--write-midx` option for callers that wish to
persist a multi-pack index in their repository while repacking.
There are two existing alternatives to this new flag, but they don't
cover our particular use-case. These alternatives are:
- Call 'git multi-pack-index write' after running 'git repack', or
- Set 'GIT_TEST_MULTI_PACK_INDEX=1' in your environment when running
'git repack'.
The former works, but introduces a gap in bitmap coverage between
repacking and writing a new MIDX (since the repack may have deleted a
pack included in the existing MIDX, invalidating it altogether).
Setting the 'GIT_TEST_' environment variable is obviously unsupported.
In fact, even if it were supported officially, it still wouldn't work,
because it generates the MIDX *after* redundant packs have been dropped,
leading to the same issue as above.
Introduce a new option which eliminates this race by teaching `git
repack` to generate the MIDX at the critical point: after the new packs
have been written and moved into place, but before the redundant packs
have been removed.
This option is compatible with `git repack`'s '--bitmap' option (it
changes the interpretation to be: "write a bitmap corresponding to the
MIDX after one has been generated").
There is a little bit of additional noise in the patch below to avoid
repeating ourselves when selecting which packs to delete. Instead of a
single loop as before (where we iterate over 'existing_packs', decide if
a pack is worth deleting, and if so, delete it), we have two loops (the
first where we decide which ones are worth deleting, and the second
where we actually do the deleting). This makes it so we have a single
check we can make consistently when (1) telling the MIDX which packs we
want to exclude, and (2) actually unlinking the redundant packs.
There is also a tiny change to short-circuit the body of
write_midx_included_packs() when no packs remain in the case of an empty
repository. The MIDX code does not handle this, so avoid trying to
generate a MIDX covering zero packs in the first place.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 29 Sep 2021 01:55:12 +0000 (21:55 -0400)]
builtin/repack.c: rename variables that deal with non-kept packs
The new variable `existing_kept_packs` (and corresponding parameter
`fname_kept_list`) added by the previous patch make it seem like
`existing_packs` and `fname_list` are each subsets of the other two
respectively.
In reality, each pair is disjoint: one stores the packs without .keep
files, and the other stores the packs with .keep files. Rename each to
more clearly reflect this.
Suggested-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 29 Sep 2021 01:55:10 +0000 (21:55 -0400)]
builtin/repack.c: keep track of existing packs unconditionally
In order to be able to write a multi-pack index during repacking, `git
repack` must keep track of which packs it wants to write into the MIDX.
This set is the union of existing packs which will not be deleted,
new pack(s) generated as a result of the repack, and .keep packs.
Prior to this patch, `git repack` populated the list of existing packs
only when repacking all-into-one (i.e., with `-A` or `-a`), but we will
soon need to know this list when repacking when writing a MIDX without
a-i-o.
Populate the list of existing packs unconditionally, and guard removing
packs from that list only when repacking a-i-o.
Additionally, keep track of filenames of kept packs separately, since
this, too, will be used in an upcoming patch.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 29 Sep 2021 01:55:07 +0000 (21:55 -0400)]
midx: preliminary support for `--refs-snapshot`
To figure out which commits we can write a bitmap for, the multi-pack
index/bitmap code does a reachability traversal, marking any commit
which can be found in the MIDX as eligible to receive a bitmap.
This approach will cause a problem when multi-pack bitmaps are able to
be generated from `git repack`, since the reference tips can change
during the repack. Even though we ignore commits that don't exist in
the MIDX (when doing a scan of the ref tips), it's possible that a
commit in the MIDX reaches something that isn't.
This can happen when a multi-pack index contains some pack which refers
to loose objects (e.g., if a pack was pushed after starting the repack
but before generating the MIDX which depends on an object which is
stored as loose in the repository, and by definition isn't included in
the multi-pack index).
By taking a snapshot of the references before we start repacking, we can
close that race window. In the above scenario (where we have a packed
object pointing at a loose one), we'll either (a) take a snapshot of the
references before seeing the packed one, or (b) take it after, at which
point we can guarantee that the loose object will be packed and included
in the MIDX.
This patch does just that. It writes a temporary "reference snapshot",
which is a list of OIDs that are at the ref tips before writing a
multi-pack bitmap. References that are "preferred" (i.e,. are a suffix
of at least one value of the 'pack.preferBitmapTips' configuration) are
marked with a special '+'.
The format is simple: one line per commit at each tip, with an optional
'+' at the beginning (for preferred references, as described above).
When provided, the reference snapshot is used to drive bitmap selection
instead of the MIDX code doing its own traversal. When it isn't
provided, the usual traversal takes place instead.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 29 Sep 2021 01:55:04 +0000 (21:55 -0400)]
builtin/multi-pack-index.c: support `--stdin-packs` mode
To power a new `--write-midx` mode, `git repack` will want to write a
multi-pack index containing a certain set of packs in the repository.
This new option will be used by `git repack` to write a MIDX which
contains only the packs which will survive after the repack (that is, it
will exclude any packs which are about to be deleted).
This patch effectively exposes the function implemented in the previous
commit via the `git multi-pack-index` builtin. An alternative approach
would have been to call that function from the `git repack` builtin
directly, but this introduces awkward problems around closing and
reopening the object store, so the MIDX will be written out-of-process.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 29 Sep 2021 01:55:01 +0000 (21:55 -0400)]
midx: expose `write_midx_file_only()` publicly
Expose a variant of the write_midx_file() function which ignores packs
that aren't included in an explicit "allow" list.
This will be used in an upcoming patch to power a new `--stdin-packs`
mode of `git multi-pack-index write` for callers that only want to
include certain packs in a MIDX (and ignore any packs which may have
happened to enter the repository independently, e.g., from pushes).
Those patches will provide test coverage for this new function.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Makefile: restrict -Wpedantic and -Wno-pedantic-ms-format better
6a8cbc41ba (developer: enable pedantic by default, 2021-09-03)
enables pedantic mode in as many compilers as possible to help gather
feedback on future tightening, so lets do so.
-Wpedantic is missing in some really old gcc 4 versions so lets restrict
it to gcc5 and clang4 (it does work in clang3 AFAIK, but it will be
unlikely that a developer will use such an old compiler anyway).
MinGW gcc is the only one which has -Wno-pedantic-ms-format, and while
that is available also in older compilers, the Windows SDK provides gcc10
so lets aim for that.
Note that in order to target the flag to only Windows, additional changes
were needed in config.mak.uname to propagate the OS detection which also
did some minor refactoring, but which is functionaly equivalent.
Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
parse-options.h: move PARSE_OPT_SHELL_EVAL between enums
Fix a bad landmine of a bug which has been with us ever since
PARSE_OPT_SHELL_EVAL was added in 47e9cd28f8a (parseopt: wrap
rev-parse --parseopt usage for eval consumption, 2010-06-12).
It's an argument to parse_options() and should therefore be in "enum
parse_opt_flags", but it was added to the per-option "enum
parse_opt_option_flags" by mistake.
Therefore as soon as we'd have an enum member in the former that
reached its value of "1 << 8" we'd run into a seemingly bizarre bug
where that new option would turn on the unrelated PARSE_OPT_SHELL_EVAL
in "git rev-parse --parseopt" by proxy.
I manually checked that no other enum members suffered from such
overlap, by setting the values to non-overlapping values, and making
the relevant codepaths BUG() out if the given value was above/below
the expected (excluding flags=0 in the case of "enum
parse_opt_flags").
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Tue, 28 Sep 2021 22:15:42 +0000 (15:15 -0700)]
Merge branch 'jk/ref-paranoia' into jt/no-abuse-alternate-odb-for-submodules
* jk/ref-paranoia: (71 commits)
refs: drop "broken" flag from for_each_fullref_in()
ref-filter: drop broken-ref code entirely
ref-filter: stop setting FILTER_REFS_INCLUDE_BROKEN
repack, prune: drop GIT_REF_PARANOIA settings
refs: turn on GIT_REF_PARANOIA by default
refs: omit dangling symrefs when using GIT_REF_PARANOIA
refs: add DO_FOR_EACH_OMIT_DANGLING_SYMREFS flag
refs-internal.h: reorganize DO_FOR_EACH_* flag documentation
refs-internal.h: move DO_FOR_EACH_* flags next to each other
t5312: be more assertive about command failure
t5312: test non-destructive repack
t5312: create bogus ref as necessary
t5312: drop "verbose" helper
t5600: provide detached HEAD for corruption failures
t5516: don't use HEAD ref for invalid ref-deletion tests
t7900: clean up some more broken refs
The eighth batch
t0000: avoid masking git exit value through pipes
tree-diff: fix leak when not HAVE_ALLOCA_H
pack-revindex.h: correct the time complexity descriptions
...
refs/ref-cache.[ch]: remove "incomplete" from create_dir_entry()
Remove the now-unused "incomplete" parameter from create_dir_entry(),
all its callers specify it as "1", so let's drop the "incomplete=0"
case. The last caller to use it was search_for_subdir(), but that code
was removed in the preceding commit.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
This function was added in 3dce444f178 (refs: add a backend method
structure, 2016-09-04), but has never been used by anything. The only
caller that might care uses find_ref_storage_backend() directly.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The git_config_key_is_valid() function got left behind in a
refactoring in a9bcf6586d1 (alias: use the early config machinery to
expand aliases, 2017-06-14),
It previously had two users when it was added in 9e9de18f1ad (config:
silence warnings for command names with invalid keys, 2015-08-24), and
after 6a1e1bc0a15 (pager: use callbacks instead of configset,
2016-09-12) only one remained.
By removing it we can get rid of the "quiet" branches in this
function, as well as cases where "store_key" is NULL, for which there
are no other users.
Out of the 5 callers of git_config_parse_key() only one needs to pass
a non-NULL "size_t *baselen_", so we could remove the third parameter
from the public interface. I did not find that potential
simplification to be worthwhile.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
string-list.[ch]: remove string_list_init() compatibility function
Remove this function left over to accommodate in-flight changes, see 770fedaf9fb (string-list.[ch]: add a string_list_init_{nodup,dup}(),
2021-07-01) for the recent change to add
"string_list_init_{nodup,dup}()" initializers.
There was only one user of the API left in remote-curl.c. I don't know
why I didn't include this change to remote-curl.c in bc40dfb10a0 (string-list.h users: change to use *_{nodup,dup}(),
2021-07-01), perhaps I just missed it.
In any case, let's change that one user to use the new API, as of
writing this there are no in-flight changes that use, so this seems
like a good time to drop this before we get any new users of this
compatibility API.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Tue, 28 Sep 2021 20:06:53 +0000 (13:06 -0700)]
Merge branch 'jk/reduce-malloc-in-v2-servers'
Code cleanup to limit memory consumption and tighten protocol
message parsing.
* jk/reduce-malloc-in-v2-servers:
ls-refs: reject unknown arguments
serve: reject commands used as capabilities
serve: reject bogus v2 "command=ls-refs=foo"
docs/protocol-v2: clarify some ls-refs ref-prefix details
ls-refs: ignore very long ref-prefix counts
serve: drop "keys" strvec
serve: provide "receive" function for session-id capability
serve: provide "receive" function for object-format capability
serve: add "receive" method for v2 capabilities table
serve: return capability "value" from get_capability()
serve: rename is_command() to parse_command()
The previous changes modified the behavior of 'git add', 'git rm', and
'git mv' to not adjust paths outside the sparse-checkout cone, even if
they exist in the working tree and their cache entries lack the
SKIP_WORKTREE bit. The intention is to warn users that they are doing
something potentially dangerous. The '--sparse' option was added to each
command to allow careful users the same ability they had before.
To improve the discoverability of this new functionality, add a message
to advice.updateSparsePath that mentions the existence of the option.
The previous set of changes also modified the purpose of this message to
include possibly a list of paths instead of only a list of pathspecs.
Make the warning message more clear about this new behavior.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since cmd_mv() does not operate on cache entries and instead directly
checks the filesystem, we can only use path_in_sparse_checkout() as a
mechanism for seeing if a path is sparse or not. Be sure to skip
returning a failure if '-k' is specified.
To ensure that the advice around sparse paths is the only reason a move
failed, be sure to check this as the very last thing before inserting
into the src_for_dst list.
The tests cover a variety of cases such as whether the target is tracked
or untracked, and whether the source or destination are in or outside of
the sparse-checkout definition.
Helped-by: Matheus Tavares Bernardino <matheus.bernardino@usp.br> Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
If a path does not match the sparse-checkout cone but is somehow missing
the SKIP_WORKTREE bit, then 'git rm' currently succeeds in removing the
file. One reason a user might be in this situation is a merge conflict
outside of the sparse-checkout cone. Removing such a file might be
problematic for users who are not sure what they are doing.
Add a check to path_in_sparse_checkout() when 'git rm' is checking if a
path should be considered for deletion. Of course, this check is ignored
if the '--sparse' option is specified, allowing users who accept the
risks to continue with the removal.
This also removes a confusing behavior where a user asks for a directory
to be removed, but only the entries that are within the sparse-checkout
definition are removed. Now, 'git rm <dir>' will fail without '--sparse'
and will succeed in removing all contained paths with '--sparse'.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
As we did previously in 'git add', add a '--sparse' option to 'git rm'
that allows modifying paths outside of the sparse-checkout definition.
The existing checks in 'git rm' are restricted to tracked files that
have the SKIP_WORKTREE bit in the current index. Future changes will
cause 'git rm' to reject removing paths outside of the sparse-checkout
definition, even if they are untracked or do not have the SKIP_WORKTREE
bit.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
We added checks for path_in_sparse_checkout() to portions of 'git add'
that add warnings and prevent stagins a modification, but we skipped the
--renormalize mode. Update renormalize_tracked_files() to ignore cache
entries whose path is outside of the sparse-checkout cone (unless
--sparse is provided). Add a test in t3705.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
We added checks for path_in_sparse_checkout() to portions of 'git add'
that add warnings and prevent staging a modification, but we skipped the
--chmod mode. Update chmod_pathspec() to ignore cache entries whose path
is outside of the sparse-checkout cone (unless --sparse is provided).
Add a test in t3705.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
We previously modified 'git add' to refuse updating index entries
outside of the sparse-checkout cone. This is justified to prevent users
from accidentally getting into a confusing state when Git removes those
files from the working tree at some later point.
Unfortunately, this caused some workflows that were previously possible
to become impossible, especially around merge conflicts outside of the
sparse-checkout cone. These were documented in tests within t1092.
We now re-enable these workflows using a new '--sparse' option to 'git
add'. This allows users to signal "Yes, I do know what I'm doing with
these files," and accept the consequences of the files leaving the
worktree later.
We delay updating the advice message until implementing a similar option
in 'git rm' and 'git mv'.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When 'git add' adds a tracked file that is outside of the
sparse-checkout cone, it checks the SKIP_WORKTREE bit to see if the file
exists outside of the sparse-checkout cone. This is usually correct,
except in the case of a merge conflict outside of the cone.
Modify add_pathspec_matched_against_index() to be more careful about
paths by checking the sparse-checkout patterns in addition to the
SKIP_WORKTREE bit. This causes 'git add' to no longer allow files
outside of the cone that removed the SKIP_WORKTREE bit due to a merge
conflict.
With only this change, users will only be able to add the file after
adding the file to the sparse-checkout cone. A later change will allow
users to force adding even though the file is outside of the
sparse-checkout cone.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The add_files() method in builtin/add.c takes a set of untracked files
that are being added by the input pathspec and inserts them into the
index. If these files are outside of the sparse-checkout cone, then they
gain the SKIP_WORKTREE bit at some point. However, this was not checked
before inserting into the index, so these files are added even though we
want to avoid modifying the index outside of the sparse-checkout cone.
Add a check within add_files() for these files and write the advice
about files outside of the sparse-checkout cone.
This behavior change modifies some existing tests within t1092. These
tests intended to document how a user could interact with the existing
behavior in place. Many of these tests need to be marked as expecting
failure. A future change will allow these tests to pass by adding a flag
to 'git add' that allows users to modify index entries outside of the
sparse-checkout cone.
The 'submodule handling' test is intended to document what happens to
directories that contain a submodule when the sparse index is enabled.
It is not trying to say that users should be able to add submodules
outside of the sparse-checkout cone, so that test can be modified to
avoid that operation.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Within match_pathname(), one successful matching category happens when
the pattern is equal to its non-wildcard prefix. At this point, we have
checked that the input 'pathname' matches the pattern up to the prefix
length, and then we subtraced that length from both 'patternlen' and
'namelen'.
In the case of a directory match, this prefix match should be
sufficient. However, the success condition only cared about _exact_
equality here. Instead, we should allow any path that agrees on this
prefix in the case of PATTERN_FLAG_MUSTBEDIR.
This case was not tested before because of the way unpack_trees() would
match a parent directory before visiting the contained paths. This
approach is changing, so we must change this comparison.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When matching a path against a list of patterns, the ones that require a
directory match previously did not work when a filename is specified.
This was fine when all pattern-matching was done within methods such as
unpack_trees() that check a directory before recursing into the
contained files. However, other commands will start matching individual
files against pattern lists without that recursive approach.
The last_matching_pattern_from_list() logic performs some checks on the
filetype of a path within the index when the PATTERN_FLAG_MUSTBEDIR flag
is set. This works great when setting SKIP_WORKTREE bits within
unpack_trees(), but doesn't work well when passing an arbitrary path
such as a file within a matching directory.
We extract the logic around determining the file type, but attempt to
avoid checking the filesystem if the parent directory already matches
the sparse-checkout patterns. The new path_matches_dir_pattern() method
includes a 'path_parent' parameter that is used to store the parent
directory of 'pathname' between multiple pattern matching tests. This is
loaded lazily, only on the first pattern it finds that has the
PATTERN_FLAG_MUSTBEDIR flag.
If we find that a path has a parent directory, we start by checking to
see if that parent directory matches the pattern. If so, then we do not
need to query the index for the type (which can be expensive). If we
find that the parent does not match, then we still must check the type
from the index for the given pathname.
Note that this does not affect cone mode pattern matching, but instead
the more general -- and slower -- full pattern set. Thus, this does not
affect the sparse index.
Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add some tests to demonstrate the current behavior around adding files
outside of the sparse-checkout cone. Currently, untracked files are
handled differently from tracked files. A future change will make these
cases be handled the same way.
Further expand checking that a failed 'git add' does not stage changes
to the index.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit b681b191 introduced the support of systemd timers for git
maintenance.
A test is leveraging the `systemd-analyze verify` utility to verify the
correctness of the systemd unit files generated by git.
But on some systems, although the `systemd-analyze` tool is installed
and supports the `verify` subcommand, it fails with some permission
errors.
So, instead of only checking if the `verify` subcommand exists, a more
reliable way of detecting whether `systemd-analyze verify` can be used
is to try to use it.
The SYSTEMD_ANALYZE prerequisite is now trying to run `systemd-analyze
verify` on a systemd unit file which is shipped by systemd itself.
We can reasonably think that, on systemd hosts, this file is present and
valid.
Signed-off-by: Lénaïc Huard <lenaic@lhuard.fr> Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/blame.c: refactor commit_info_init() to COMMIT_INFO_INIT macro
Remove the commit_info_init() function addded in ea02ffa3857 (mailmap:
simplify map_user() interface, 2013-01-05) and instead initialize the
"struct commit_info" with a macro.
This is the more idiomatic pattern in the codebase, and doesn't leave
us wondering when we see the *_init() function if this struct needs
more complex initialization than a macro can provide.
The get_commit_info() function is only called by the three callers
being changed here immediately after initializing the struct with the
macros, so by moving the initialization to the callers we don't need
to do it in get_commit_info() anymore.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
daemon.c: refactor hostinfo_init() to HOSTINFO_INIT macro
Remove the hostinfo_init() function added in 01cec54e135 (daemon:
deglobalize hostname information, 2015-03-07) and instead initialize
the "struct hostinfo" with a macro.
This is the more idiomatic pattern in the codebase, and doesn't leave
us wondering when we see the *_init() function if this struct needs
more complex initialization than a macro can provide.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
cbtree.h: define cb_init() in terms of CBTREE_INIT
Use the same pattern for cb_init() as the one established in the
recent refactoring of other such patterns in 5726a6b4012 (*.c *_init(): define in terms of corresponding *_INIT
macro, 2021-07-01).
It has been pointed out[1] that we could perhaps use this C99
replacement of using a compound literal for all of these:
*t = (struct cb_tree){ 0 };
But let's just stick to the existing pattern established in 5726a6b4012 for now, we can leave another weather balloon for some
other time.
Move various *_INIT macros to use designated initializers. This helps
readability. I've only picked those leftover macros that were not
touched by another in-flight series of mine which changed others, but
also how initialization was done.
In the case of SUBMODULE_ALTERNATE_SETUP_INIT I've left an explicit
initialization of "error_mode", even though
SUBMODULE_ALTERNATE_ERROR_IGNORE itself is defined as "0". Let's not
peek under the hood and assume that enum fields we know the value of
will stay at "0".
The change to "TESTSUITE_INIT" in "t/helper/test-run-command.c" was
part of an earlier on-list version[1] of c90be786da9 (test-tool
run-command: fix flip-flop init pattern, 2021-09-11).
Change the initialization of "struct strbuf" changed in cbc0f81d96f (strbuf: use designated initializers in STRBUF_INIT,
2017-07-10) to omit specifying "alloc" and "len", as we do with other
"alloc" and "len" (or "nr") in similar structs.
Let's likewise omit the explicit initialization of all fields in the
"struct ipc_client_connect_option" struct added in 59c7b88198a (simple-ipc: add win32 implementation, 2021-03-15).
Do the same for a few other initializers, e.g. STRVEC_INIT and
CACHE_DEF_INIT.
Finally, start incrementally changing the same pattern in
"t/helper/test-run-command.c". This change was part of an earlier
on-list version[1] of c90be786da9 (test-tool run-command: fix
flip-flop init pattern, 2021-09-11).
*.[ch] *_INIT macros: use { 0 } for a "zero out" idiom
In C it isn't required to specify that all members of a struct are
zero'd out to 0, NULL or '\0', just providing a "{ 0 }" will
accomplish that.
Let's also change code that provided N zero'd fields to just
provide one, and change e.g. "{ NULL }" to "{ 0 }" for
consistency. I.e. even if the first member is a pointer let's use "0"
instead of "NULL". The point of using "0" consistently is to pick one,
and to not have the reader wonder why we're not using the same pattern
everywhere.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
This macro was added and used in c68f8375760 (implement fetching of
moved submodules, 2017-10-16) but its last user went away in be76c212823 (fetch: ensure submodule objects fetched, 2018-12-06).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Makefile: pass -Wno-pendantic under GENERATE_COMPILATION_DATABASE=yes
The same bug fixed in the "COMPUTE_HEADER_DEPENDENCIES=auto" mode in
the preceding commit was also present with
"GENERATE_COMPILATION_DATABASE=yes". Let's fix it so it works again
with "DEVOPTS=1".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Comment important codepaths regarding nuking untracked files/dirs
In the last few commits we focused on code in unpack-trees.c that
mistakenly removed untracked files or directories. There may be more of
those, but in this commit we change our focus: callers of toplevel
commands that are expected to remove untracked files or directories.
As noted previously, we have toplevel commands that are expected to
delete untracked files such as 'read-tree --reset', 'reset --hard', and
'checkout --force'. However, that does not mean that other highlevel
commands that happen to call these other commands thought about or
conveyed to users the possibility that untracked files could be removed.
Audit the code for such callsites, and add comments near existing
callsites to mention whether these are safe or not.
My auditing is somewhat incomplete, though; it skipped several cases:
* git-rebase--preserve-merges.sh: is in the process of being
deprecated/removed, so I won't leave a note that there are
likely more bugs in that script.
* contrib/git-new-workdir: why is the -f flag being used in a new
empty directory?? It shouldn't hurt, but it seems useless.
* git-p4.py: Don't see why -f is needed for a new dir (maybe it's
not and is just superfluous), but I'm not at all familiar with
the p4 stuff
* git-archimport.perl: Don't care; arch is long since dead
* git-cvs*.perl: Don't care; cvs is long since dead
Also, the reset --hard in builtin/worktree.c looks safe, due to only
running in an empty directory.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Traditionally, unpack_trees_options->reset was used to signal that it
was okay to delete any untracked files in the way. This was used by
`git read-tree --reset`, but then started appearing in other places as
well. However, many of the other uses should not be deleting untracked
files in the way. Change this value to an enum so that a value of 1
(i.e. "true") can be split into two:
UNPACK_RESET_PROTECT_UNTRACKED,
UNPACK_RESET_OVERWRITE_UNTRACKED
In order to catch accidental misuses (i.e. where folks call it the way
they traditionally used to), define the special enum value of
UNPACK_RESET_INVALID = 1
which will trigger a BUG().
Modify existing callers so that
read-tree --reset
reset --hard
checkout --force
continue using the UNPACK_RESET_OVERWRITE_UNTRACKED logic, while other
callers, including
am
checkout without --force
stash (though currently dead code; reset always had a value of 0)
numerous callers from rebase/sequencer to reset_head()
will use the new UNPACK_RESET_PROTECT_UNTRACKED value.
Also, note that it has been reported that 'git checkout <treeish>
<pathspec>' currently also allows overwriting untracked files[1]. That
case should also be fixed, but it does not use unpack_trees() and thus
is outside the scope of the current changes.
Remove ignored files by default when they are in the way
Change several commands to remove ignored files by default when they are
in the way. Since some commands (checkout, merge) take a
--no-overwrite-ignore option to allow the user to configure this, and it
may make sense to add that option to more commands (and in the case of
merge, actually plumb that configuration option through to more of the
backends than just the fast-forwarding special case), add little
comments about where such flags would be used.
Incidentally, this fixes a test failure in t7112.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
unpack-trees: introduce preserve_ignored to unpack_trees_options
Currently, every caller of unpack_trees() that wants to ensure ignored
files are overwritten by default needs to:
* allocate unpack_trees_options.dir
* flip the DIR_SHOW_IGNORED flag in unpack_trees_options.dir->flags
* call setup_standard_excludes
AND then after the call to unpack_trees() needs to
* call dir_clear()
* deallocate unpack_trees_options.dir
That's a fair amount of boilerplate, and every caller uses identical
code. Make this easier by instead introducing a new boolean value where
the default value (0) does what we want so that new callers of
unpack_trees() automatically get the appropriate behavior. And move all
the handling of unpack_trees_options.dir into unpack_trees() itself.
While preserve_ignored = 0 is the behavior we feel is the appropriate
default, we defer fixing commands to use the appropriate default until a
later commit. So, this commit introduces several locations where we
manually set preserve_ignored=1. This makes it clear where code paths
were previously preserving ignored files when they should not have been;
a future commit will flip these to instead use a value of 0 to get the
behavior we want.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
read-tree, merge-recursive: overwrite ignored files by default
This fixes a long-standing patchwork of ignored files handling in
read-tree and merge-recursive, called out and suggested by Junio long
ago. Quoting from commit dcf0c16ef1 ("core.excludesfile clean-up"
2007-11-16):
git-read-tree takes --exclude-per-directory=<gitignore>,
not because the flexibility was needed. Again, this was
because the option predates the standardization of the ignore
files.
...
On the other hand, I think it makes perfect sense to fix
git-read-tree, git-merge-recursive and git-clean to follow the
same rule as other commands. I do not think of a valid use case
to give an exclude-per-directory that is nonstandard to
read-tree command, outside a "negative" test in the t1004 test
script.
This patch is the first step to untangle this mess.
The next step would be to teach read-tree, merge-recursive and
clean (in C) to use setup_standard_excludes().
History shows each of these were partially or fully fixed:
* clean was taught the new trick in 1617adc7a0 ("Teach git clean to
use setup_standard_excludes()", 2007-11-14).
* read-tree was primarily used by checkout & merge scripts. checkout
and merge later became builtins and were both fixed to use the new
setup_standard_excludes() handling in fc001b526c ("checkout,merge:
loosen overwriting untracked file check based on info/exclude",
2011-11-27). So the primary users were fixed, though read-tree
itself was not.
* merge-recursive has now been replaced as the default merge backend
by merge-ort. merge-ort fixed this by using
setup_standard_excludes() starting early in its implementation; see
commit 6681ce5cf6 ("merge-ort: add implementation of checkout()",
2020-12-13), largely due to its design depending on checkout() and
thus being influenced by the checkout code. However,
merge-recursive itself was not fixed here, in part because its
design meant it had difficulty differentiating between untracked
files, ignored files, leftover tracked files that haven't been
removed yet due to order of processing files, and files written by
itself due to collisions).
Make the conversion more complete by now handling read-tree and
handling at least the unpack_trees() portion of merge-recursive. While
merge-recursive is on its way out, fixing the unpack_trees() portion is
easy and facilitates some of the later changes in this series. Note
that fixing read-tree makes the --exclude-per-directory option to
read-tree useless, so we remove it from the documentation (though we
continue to accept it if passed).
The read-tree changes happen to fix a bug in t1013.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
lazyload.h: use an even more generic function pointer than FARPROC
gcc will helpfully raise a -Wcast-function-type warning when casting
between functions that might have incompatible return types
(ex: GetUserNameExW returns bool which is only half the size of the
return type from FARPROC which is long long), so create a new type that
could be used as a completely generic function pointer and cast through
it instead.
Additionaly remove the -Wno-incompatible-pointer-types temporary
flag added in 27e0c3c (win32: allow building with pedantic mode
enabled, 2021-09-03), as it will be no longer needed.
Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>