Commit Graph

206 Commits

Author SHA1 Message Date
Ævar Arnfjörð Bjarmason
07047d6829 cocci: apply "pending" index-compatibility to some "builtin/*.c"
Apply "index-compatibility.pending.cocci" rule to "builtin/*", but
exclude those where we conflict with in-flight changes.

As a result some of them end up using only "the_index", so let's have
them use the more narrow "USE_THE_INDEX_VARIABLE" rather than
"USE_THE_INDEX_COMPATIBILITY_MACROS".

Manual changes not made by coccinelle, that were squashed in:

* Whitespace-wrap argument lists for repo_hold_locked_index(),
  repo_read_index_preload() and repo_refresh_and_write_index(), in cases
  where the line became too long after the transformation.
* Change "refresh_cache()" to "refresh_index()" in a comment in
  "builtin/update-index.c".
* For those whose call was followed by perror("<macro-name>"), change
  it to perror("<function-name>"), referring to the new function.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
dc594180d9 cocci & cache.h: apply variable section of "pending" index-compatibility
Mostly apply the part of "index-compatibility.pending.cocci" that
renames the global variables like "active_nr", which are a shorthand
to referencing (in that case) a struct member as "the_index.cache_nr".

In doing so move more of "index-compatibility.pending.cocci" to
"index-compatibility.cocci".

In the case of "active_nr" we'd have a textual conflict with
"ab/various-leak-fixes" in "next"[1]. Let's exclude that specific case
while moving the rule over from "pending".

1. 407b94280f8 (commit: discard partial cache before (re-)reading it,
   2022-11-08)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Junio C Hamano
7b9b634ca5 Merge branch 'ab/doc-synopsis-and-cmd-usage'
The short-help text shown by "git cmd -h" and the synopsis text
shown at the beginning of "git help cmd" have been made more
consistent.

* ab/doc-synopsis-and-cmd-usage: (34 commits)
  tests: assert consistent whitespace in -h output
  tests: start asserting that *.txt SYNOPSIS matches -h output
  doc txt & -h consistency: make "worktree" consistent
  worktree: define subcommand -h in terms of command -h
  reflog doc: list real subcommands up-front
  doc txt & -h consistency: make "commit" consistent
  doc txt & -h consistency: make "diff-tree" consistent
  doc txt & -h consistency: use "[<label>...]" for "zero or more"
  doc txt & -h consistency: make "annotate" consistent
  doc txt & -h consistency: make "stash" consistent
  doc txt & -h consistency: add missing options
  doc txt & -h consistency: use "git foo" form, not "git-foo"
  doc txt & -h consistency: make "bundle" consistent
  doc txt & -h consistency: make "read-tree" consistent
  doc txt & -h consistency: make "rerere" consistent
  doc txt & -h consistency: add missing options and labels
  doc txt & -h consistency: make output order consistent
  doc txt & -h consistency: add or fix optional "--" syntax
  doc txt & -h consistency: fix mismatching labels
  doc SYNOPSIS & -h: use "-" to separate words in labels, not "_"
  ...
2022-10-28 11:26:54 -07:00
Ævar Arnfjörð Bjarmason
d9054a19ed doc txt & -h consistency: add missing options
Change those built-in commands that were attempting to exhaustively
list the options in the "-h" output to actually do so, and always
have *.txt documentation know about the exhaustive list of options.

Let's also fix the documentation and -h output for those built-in
commands where the *.txt and -h output was a mismatch of missing
options on both sides.

In the case of "interpret-trailers" fixing the missing options reveals
that the *.txt version was implicitly claiming that the command had
two operating modes, which a look at the -h version (and studying the
documentation) will show is not the case.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-10-13 09:32:57 -07:00
Junio C Hamano
fdbfac60fd Merge branch 'jk/fsck-on-diet'
"git fsck" failed to release contents of tree objects already used
from the memory, which has been fixed.

* jk/fsck-on-diet:
  parse_object_buffer(): respect save_commit_buffer
  fsck: turn off save_commit_buffer
  fsck: free tree buffers after walking unreachable objects
2022-10-10 10:08:39 -07:00
Jeff King
51b27747e5 parse_object_buffer(): respect save_commit_buffer
If the global variable "save_commit_buffer" is set to 0, then
parse_commit() will throw away the commit object data after parsing it,
rather than sticking it into a commit slab. This goes all the way back
to 60ab26de99 ([PATCH] Avoid wasting memory in git-rev-list,
2005-09-15).

But there's another code path which may similarly stash the buffer:
parse_object_buffer(). This is where we end up if we parse a commit via
parse_object(), and it's used directly in a few other code paths like
git-fsck.

The original goal of 60ab26de99 was avoiding extra memory usage for
rev-list. And there it's not all that important to catch parse_object().
We use that function only for looking at the tips of the traversal, and
the majority of the commits are parsed by following parent links, where
we use parse_commit() directly. So we were wasting some memory, but only
a small portion.

It's much easier to see the effect with fsck. Since we now turn off
save_commit_buffer by default there, we _should_ be able to drop the
freeing of the commit buffer in fsck_obj(). But if we do so (taking the
first hunk of this patch without the rest), then the peak heap of "git
fsck" in a clone of git.git goes from 136MB to 194MB. Teaching
parse_object_buffer() to respect save_commit_buffer brings that down to
134.5MB (it's hard to tell from massif's output, but I suspect the
savings comes from avoiding the overhead of the mostly-empty commit
slab).

Other programs should see a small improvement. Both "rev-list --all" and
"fsck --connectivity-only" improve by a few hundred kilobytes, as they'd
avoid loading the tip objects of their traversals.

Most importantly, no code should be hurt by doing this. Any program that
turns off save_commit_buffer is already making the assumption that any
commit it sees may need to have its object data loaded on demand, as it
doesn't know which ones were parsed by parse_commit() versus
parse_object(). Not to mention that anything parsed by the commit graph
may be in the same boat, even if save_commit_buffer was not disabled.

This should be the only spot that needs to be fixed. Grepping for
set_commit_buffer() shows that this and parse_commit() are the only
relevant calls.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-09-22 11:40:47 -07:00
Jeff King
069e445256 fsck: turn off save_commit_buffer
When parsing a commit, the default behavior is to stuff the original
buffer into a commit_slab (which takes ownership of it). But for a tool
like fsck, this isn't useful. While we may look at the buffer further as
part of fsck_commit(), we'll always do so through a separate pointer;
attaching the buffer to the slab doesn't help.

Worse, it means we have to remember to free the commit buffer in all
call paths. We do so in fsck_obj(), which covers a regular "git fsck".
But with "--connectivity-only", we forget to do so in both
traverse_one_object(), which covers reachable objects, and
mark_unreachable_referents(), which covers unreachable ones. As a
result, that mode ends up storing an uncompressed copy of every commit
on the heap at once.

We could teach the code paths for --connectivity-only to also free
commit buffers. But there's an even easier fix: we can just turn off the
save_commit_buffer flag, and then we won't attach them to the commits in
the first place.

This reduces the peak heap of running "git fsck --connectivity-only" in
a clone of linux.git from ~2GB to ~1GB. According to massif, the
remaining memory goes where you'd expect: the object structs themselves,
the obj_hash containing them, and the delta base cache.

Note that we'll leave the call to free commit buffers in fsck_obj() for
now; it's not quite redundant because of a related bug that we'll fix in
a subsequent commit.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-09-22 11:40:11 -07:00
Jeff King
fbce4fa9ae fsck: free tree buffers after walking unreachable objects
After calling fsck_walk(), a tree object struct may be left in the
parsed state, with the full tree contents available via tree->buffer.
It's the responsibility of the caller to free these when it's done with
the object to avoid having many trees allocated at once.

In a regular "git fsck", we hit fsck_walk() only from fsck_obj(), which
does call free_tree_buffer(). Likewise for "--connectivity-only", we see
most objects via traverse_one_object(), which makes a similar call.

The exception is in mark_unreachable_referents(). When using both
"--connectivity-only" and "--dangling" (the latter of which is the
default), we walk all of the unreachable objects, and there we forget to
free. Most cases would not notice this, because they don't have a lot of
unreachable objects, but you can make a pathological case like this:

  git clone --bare /path/to/linux.git repo.git
  cd repo.git
  rm packed-refs ;# now everything is unreachable!
  git fsck --connectivity-only

That ends up with peak heap usage ~18GB, which is (not coincidentally)
close to the size of all uncompressed trees in the repository. After
this patch, the peak heap is only ~2GB.

A few things to note:

  - it might seem like fsck_walk(), if it is parsing the trees, should
    be responsible for freeing them. But the situation is quite tricky.
    In the non-connectivity mode, after we call fsck_walk() we then
    proceed with fsck_object() which actually does the type-specific
    sanity checks on the object contents. We do pass our own separate
    buffer to fsck_object(), but there's a catch: our earlier call to
    parse_object_buffer() may have attached that buffer to the object
    struct! So by freeing it, we leave the rest of the code with a
    dangling pointer.

    Likewise, the call to fsck_walk() in index-pack is subtle. It
    attaches a buffer to the tree object that must not be freed! And
    so rather than calling free_tree_buffer(), it actually detaches it
    by setting tree->buffer to NULL.

    These cases would _probably_ be fixable by having fsck_walk() free
    the tree buffer only when it was the one who allocated it via
    parse_tree(). But that would still leave the callers responsible for
    freeing other cases, so they wouldn't be simplified. While the
    current semantics for fsck_walk() make it easy to accidentally leak
    in new callers, at least they are simple to explain, and it's not a
    function that's likely to get a lot of new call-sites.

    And in any case, it's probably sensible to fix the leak first with
    this simple patch, and try any more complicated refactoring
    separately.

  - a careful reader may notice that fsck_obj() also frees commit
    buffers, but neither the call in traverse_one_object() nor the one
    touched in this patch does so. And indeed, this is another problem
    for --connectivity-only (and accounts for most of the 2GB heap after
    this patch), but it's one we'll fix in a separate commit.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-09-22 11:30:06 -07:00
Ævar Arnfjörð Bjarmason
5cf88fd8b0 git-compat-util.h: use "UNUSED", not "UNUSED(var)"
As reported in [1] the "UNUSED(var)" macro introduced in
2174b8c75de (Merge branch 'jk/unused-annotation' into next,
2022-08-24) breaks coccinelle's parsing of our sources in files where
it occurs.

Let's instead partially go with the approach suggested in [2] of
making this not take an argument. As noted in [1] "coccinelle" will
ignore such tokens in argument lists that it doesn't know about, and
it's less of a surprise to syntax highlighters.

This undoes the "help us notice when a parameter marked as unused is
actually use" part of 9b24034754 (git-compat-util: add UNUSED macro,
2022-08-19), a subsequent commit will further tweak the macro to
implement a replacement for that functionality.

1. https://lore.kernel.org/git/220825.86ilmg4mil.gmgdl@evledraar.gmail.com/
2. https://lore.kernel.org/git/220819.868rnk54ju.gmgdl@evledraar.gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-09-01 10:49:48 -07:00
Jeff King
c006e9fa59 refs: mark unused reflog callback parameters
Functions used with for_each_reflog_ent() need to conform to a
particular interface, but not every function needs all of the
parameters. Mark the unused ones to make -Wunused-parameter happy.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-08-19 12:18:54 -07:00
Jeff King
63e14ee2d6 refs: mark unused each_ref_fn parameters
Functions used with for_each_ref(), etc, need to conform to the
each_ref_fn interface. But most of them don't need every parameter;
let's annotate the unused ones to quiet -Wunused-parameter.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-08-19 12:18:54 -07:00
Junio C Hamano
e0ad13977a fsck: do not dereference NULL while checking resolve-undo data
When we found an invalid object recorded in the resolve-undo data,
we would have ended up dereferencing NULL while fsck.  Reporting the
problem and going on to the next object is the right thing to do
here.

Noticed by SZEDER Gábor.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-11 16:26:33 -07:00
Junio C Hamano
5a5ea141e7 revision: mark blobs needed for resolve-undo as reachable
The resolve-undo extension was added to the index in cfc5789a
(resolve-undo: record resolved conflicts in a new index extension
section, 2009-12-25).  This extension records the blob object names
and their modes of conflicted paths when the path gets resolved
(e.g. with "git add"), to allow "undoing" the resolution with
"checkout -m path".  These blob objects should be guarded from
garbage-collection while we have the resolve-undo information in the
index (otherwise unresolve operation may try to use a blob object
that has already been pruned away).

But the code called from mark_reachable_objects() for the index
forgets to do so.  Teach add_index_objects_to_pending() helper to
also add objects referred to by the resolve-undo extension.

Also make matching changes to "fsck", which has code that is fairly
similar to the reachability stuff, but have parallel implementations
for all these stuff, which may (or may not) someday want to be unified.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-09 16:45:07 -07:00
Ævar Arnfjörð Bjarmason
2b7098936c run-command API users: use strvec_pushl(), not argv construction
Change a pattern of hardcoding an "argv" array size, populating it and
assigning to the "argv" member of "struct child_process" to instead
use "strvec_pushl()" to add data to the "args" member.

This implements the same behavior as before in fewer lines of code,
and moves us further towards being able to remove the "argv" member in
a subsequent commit.

Since we've entirely removed the "argv" variable(s) we can be sure
that no potential logic errors of the type discussed in a preceding
commit are being introduced here, i.e. ones where the local "argv" was
being modified after the assignment to "struct child_process"'s
"argv".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-25 22:15:07 -08:00
Junio C Hamano
2c0fa66bc8 Merge branch 'ab/fsck-unexpected-type'
Regression fix.

* ab/fsck-unexpected-type:
  object-file: free(*contents) only in read_loose_object() caller
  object-file: fix SEGV on free() regression in v2.34.0-rc2
2021-11-12 15:29:25 -08:00
Ævar Arnfjörð Bjarmason
16235e3b14 object-file: free(*contents) only in read_loose_object() caller
In the preceding commit a free() of uninitialized memory regression in
96e41f58fe (fsck: report invalid object type-path combinations,
2021-10-01) was fixed, but we'd still have an issue with leaking
memory from fsck_loose(). Let's fix that issue too.

That issue was introduced in my 31deb28f5e (fsck: don't hard die on
invalid object types, 2021-10-01). It can be reproduced under
SANITIZE=leak with the test I added in 093fffdfbe (fsck tests: add
test for fsck-ing an unknown type, 2021-10-01):

    ./t1450-fsck.sh --run=84 -vixd

In some sense it's not a problem, we lost the same amount of memory in
terms of things malloc'd and not free'd. It just moved from the "still
reachable" to "definitely lost" column in valgrind(1) nomenclature[1],
since we'd have die()'d before.

But now that we don't hard die() anymore in the library let's properly
free() it. Doing so makes this code much easier to follow, since we'll
now have one function owning the freeing of the "contents" variable,
not two.

For context on that memory management pattern the read_loose_object()
function was added in f6371f9210 (sha1_file: add read_loose_object()
function, 2017-01-13) and subsequently used in c68b489e56 (fsck:
parse loose object paths directly, 2017-01-13). The pattern of it
being the task of both sides to free() the memory has been there in
this form since its inception.

1. https://valgrind.org/docs/manual/mc-manual.html#mc-manual.leaks

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-11 13:40:43 -08:00
Junio C Hamano
7afb458e91 Merge branch 'gc/use-repo-settings'
It is wrong to read some settings directly from the config
subsystem, as things like feature.experimental can affect their
default values.

* gc/use-repo-settings:
  gc: perform incremental repack when implictly enabled
  fsck: verify multi-pack-index when implictly enabled
  fsck: verify commit graph when implicitly enabled
2021-11-01 13:48:08 -07:00
Junio C Hamano
061a21d36d Merge branch 'ab/fsck-unexpected-type'
"git fsck" has been taught to report mismatch between expected and
actual types of an object better.

* ab/fsck-unexpected-type:
  fsck: report invalid object type-path combinations
  fsck: don't hard die on invalid object types
  object-file.c: stop dying in parse_loose_header()
  object-file.c: return ULHR_TOO_LONG on "header too long"
  object-file.c: use "enum" return type for unpack_loose_header()
  object-file.c: simplify unpack_loose_short_header()
  object-file.c: make parse_loose_header_extended() public
  object-file.c: return -1, not "status" from unpack_loose_header()
  object-file.c: don't set "typep" when returning non-zero
  cat-file tests: test for current --allow-unknown-type behavior
  cat-file tests: add corrupt loose object test
  cat-file tests: test for missing/bogus object with -t, -s and -p
  cat-file tests: move bogus_* variable declarations earlier
  fsck tests: test for garbage appended to a loose object
  fsck tests: test current hash/type mismatch behavior
  fsck tests: refactor one test to use a sub-repo
  fsck tests: add test for fsck-ing an unknown type
2021-10-25 16:06:56 -07:00
Glen Choo
dc5570872f fsck: verify multi-pack-index when implictly enabled
Like the previous commit, change fsck to check the
"core_multi_pack_index" variable set in "repo-settings.c" instead of
reading the "core.multiPackIndex" config variable. This fixes a bug
where we wouldn't verify midx if the config key was missing. This bug
was introduced in 18e449f86b (midx: enable core.multiPackIndex by
default, 2020-09-25) where core.multiPackIndex was turned on by default.

Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-15 14:30:08 -07:00
Glen Choo
f30e4d854b fsck: verify commit graph when implicitly enabled
Change fsck to check the "core_commit_graph" variable set in
"repo-settings.c" instead of reading the "core.commitGraph" variable.
This fixes a bug where we wouldn't verify the commit-graph if the
config key was missing. This bug was introduced in
31b1de6a09 (commit-graph: turn on commit-graph by default, 2019-08-13),
where core.commitGraph was turned on by default.

Add tests to "t5318-commit-graph.sh" to verify that fsck checks the
commit-graph as expected for the 3 values of core.commitGraph. Also,
disable GIT_TEST_COMMIT_GRAPH in t/t0410-partial-clone.sh because some
test cases use fsck in ways that assume that commit-graph checking is
disabled.

Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-15 14:30:07 -07:00
Ævar Arnfjörð Bjarmason
96e41f58fe fsck: report invalid object type-path combinations
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.:

    $ git hash-object --stdin -w -t blob </dev/null
    e69de29bb2
    $ mv objects/e6/ objects/e7

Would emit ("[...]" used to abbreviate the OIDs):

    git fsck
    error: hash mismatch for ./objects/e7/9d[...] (expected e79d[...])
    error: e79d[...]: object corrupt or missing: ./objects/e7/9d[...]

Now we'll instead emit:

    error: e69d[...]: hash-path mismatch, found at: ./objects/e7/9d[...]

Furthermore, we'll do the right thing when the object type and its
location are bad. I.e. this case:

    $ git hash-object --stdin -w -t garbage --literally </dev/null
    8315a83d2acc4c174aed59430f9a9c4ed926440f
    $ mv objects/83 objects/84

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:

    $ git hash-object --stdin -w -t blob </dev/null
    e69de29bb2
    $ chmod 755 objects/e6/9de29bb2d1d6434b8b29ae775ad8c2e48c5391
    $ echo garbage >>objects/e6/9de29bb2d1d6434b8b29ae775ad8c2e48c5391
    $ git fsck
    error: garbage at end of loose object 'e69d[...]'
    error: unable to unpack contents of ./objects/e6/9d[...]
    error: e69d[...]: object corrupt or missing: ./objects/e6/9d[...]

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.:

    $ git hash-object --stdin -w -t garbage --literally </dev/null
    8315a83d2acc4c174aed59430f9a9c4ed926440f
    $ chmod 755 objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f
    $ echo garbage >>objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f
    $ /usr/bin/git fsck
    fatal: invalid object type
    $ ~/g/git/git fsck
    error: garbage at end of loose object '8315a83d2acc4c174aed59430f9a9c4ed926440f'
    error: unable to unpack contents of ./objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f
    error: 8315a83d2acc4c174aed59430f9a9c4ed926440f: object corrupt or missing: ./objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f
    error: 0000000000000000000000000000000000000000: object is of unknown type 'garbage': ./objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f
    [...]

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>
2021-10-01 15:06:01 -07:00
Ævar Arnfjörð Bjarmason
31deb28f5e fsck: don't hard die on invalid object types
Change the error fsck emits on invalid object types, such as:

    $ git hash-object --stdin -w -t garbage --literally </dev/null
    <OID>

From the very ungraceful error of:

    $ git fsck
    fatal: invalid object type
    $

To:

    $ 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
f6371f9210 (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>
2021-10-01 15:06:01 -07:00
Junio C Hamano
ed125c4f07 Merge branch 'ab/fsck-api-cleanup'
Last minute compilation fix.

* ab/fsck-api-cleanup:
  builtin/fsck.c: don't conflate "int" and "enum" in callback
2021-06-02 07:34:27 +09:00
Ævar Arnfjörð Bjarmason
28abf260a5 builtin/fsck.c: don't conflate "int" and "enum" in callback
Fix a warning on AIX's xlc compiler that's been emitted since my
a1aad71601 (fsck.h: use "enum object_type" instead of "int",
2021-03-28):

    "builtin/fsck.c", line 805.32: 1506-068 (W) Operation between
    types "int(*)(struct object*,enum object_type,void*,struct
    fsck_options*)" and "int(*)(struct object*,int,void*,struct
    fsck_options*)" is not allowed.

I.e. it complains about us assigning a function with a prototype "int"
where we're expecting "enum object_type".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-06-02 05:59:15 +09:00
Junio C Hamano
8e97852919 Merge branch 'ds/sparse-index-protections'
Builds on top of the sparse-index infrastructure to mark operations
that are not ready to mark with the sparse index, causing them to
fall back on fully-populated index that they always have worked with.

* ds/sparse-index-protections: (47 commits)
  name-hash: use expand_to_path()
  sparse-index: expand_to_path()
  name-hash: don't add directories to name_hash
  revision: ensure full index
  resolve-undo: ensure full index
  read-cache: ensure full index
  pathspec: ensure full index
  merge-recursive: ensure full index
  entry: ensure full index
  dir: ensure full index
  update-index: ensure full index
  stash: ensure full index
  rm: ensure full index
  merge-index: ensure full index
  ls-files: ensure full index
  grep: ensure full index
  fsck: ensure full index
  difftool: ensure full index
  commit: ensure full index
  checkout: ensure full index
  ...
2021-04-30 13:50:26 +09:00
Derrick Stolee
2227ea175f fsck: ensure full index
When verifying all blobs reachable from the index, ensure that a sparse
index has been expanded to a full one to avoid missing some blobs.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-14 13:47:11 -07:00
Jeff King
45a187cc34 lookup_unknown_object(): take a repository argument
All of the other lookup_foo() functions take a repository argument, but
lookup_unknown_object() was never converted, and it uses the_repository
internally. Let's fix that.

We could leave a wrapper that uses the_repository, but there aren't that
many calls, so we'll just convert them all. I looked briefly at each
site to see if we had a repository struct (besides the_repository) we
could pass, but none of them do (so this conversion to pass
the_repository is a pure noop in each case, though it does take us one
step closer to eventually getting rid of the_repository).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-13 13:18:46 -07:00
Ævar Arnfjörð Bjarmason
394d5d31b0 fsck.c: pass along the fsck_msg_id in the fsck_error callback
Change the fsck_error callback to also pass along the
fsck_msg_id. Before this change the only way to get the message id was
to parse it back out of the "message".

Let's pass it down explicitly for the benefit of callers that might
want to use it, as discussed in [1].

Passing the msg_type is now redundant, as you can always get it back
from the msg_id, but I'm not changing that convention. It's really
common to need the msg_type, and the report() function itself (which
calls "fsck_error") needs to call fsck_msg_type() to discover
it. Let's not needlessly re-do that work in the user callback.

1. https://lore.kernel.org/git/87blcja2ha.fsf@evledraar.gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-28 19:03:10 -07:00
Ævar Arnfjörð Bjarmason
1b32b59f9b fsck.h: move FSCK_{FATAL,INFO,ERROR,WARN,IGNORE} into an enum
Move the FSCK_{FATAL,INFO,ERROR,WARN,IGNORE} defines into a new
fsck_msg_type enum.

These defines were originally introduced in:

 - ba002f3b28 (builtin-fsck: move common object checking code to
   fsck.c, 2008-02-25)
 - f50c440730 (fsck: disallow demoting grave fsck errors to warnings,
   2015-06-22)
 - efaba7cc77 (fsck: optionally ignore specific fsck issues
   completely, 2015-06-22)
 - f27d05b170 (fsck: allow upgrading fsck warnings to errors,
   2015-06-22)

The reason these were defined in two different places is because we
use FSCK_{IGNORE,INFO,FATAL} only in fsck.c, but FSCK_{ERROR,WARN} are
used by external callbacks.

Untangling that would take some more work, since we expose the new
"enum fsck_msg_type" to both. Similar to "enum object_type" it's not
worth structuring the API in such a way that only those who need
FSCK_{ERROR,WARN} pass around a different type.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-28 19:03:10 -07:00
Ævar Arnfjörð Bjarmason
a1aad71601 fsck.h: use "enum object_type" instead of "int"
Change the fsck_walk_func to use an "enum object_type" instead of an
"int" type. The types are compatible, and ever since this was added in
355885d531 (add generic, type aware object chain walker, 2008-02-25)
we've used entries from object_type (OBJ_BLOB etc.).

So this doesn't really change anything as far as the generated code is
concerned, it just gives the compiler more information and makes this
easier to read.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-28 19:03:10 -07:00
Ævar Arnfjörð Bjarmason
fb79f5bff7 fsck.c: refactor and rename common config callback
Refactor code I recently changed in 1f3299fda9 (fsck: make
fsck_config() re-usable, 2021-01-05) so that I could use fsck's config
callback in mktag in 1f3299fda9 (fsck: make fsck_config() re-usable,
2021-01-05).

I don't know what I was thinking in structuring the code this way, but
it clearly makes no sense to have an fsck_config_internal() at all
just so it can get a fsck_options when git_config() already supports
passing along some void* data.

Let's just make use of that instead, which gets us rid of the two
wrapper functions, and brings fsck's common config callback in line
with other such reusable config callbacks.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-17 14:02:43 -07:00
Ævar Arnfjörð Bjarmason
1f3299fda9 fsck: make fsck_config() re-usable
Move the fsck_config() function from builtin/fsck.c to fsck.[ch]. This
allows for re-using it in other tools that expose fsck logic and want
to support its configuration variables.

A logical continuation of this change would be to use a common
function for all of {fetch,receive}.fsck.* and fsck.*. See
5d477a334a (fsck (receive-pack): allow demoting errors to warnings,
2015-06-22) and my own 1362df0d41 (fetch: implement fetch.fsck.*,
2018-07-27) for the relevant code.

However, those routines want to not parse the fsck.skipList into OIDs,
but rather pass them along with the --strict option to another
process. It would be possible to refactor that whole thing so we
support e.g. a "fetch." prefix, then just keep track of the skiplist
as a filename instead of parsing it, and learn to spew that all out
from our internal structures into something we can append to the
--strict option.

But instead I'm planning to re-use this in "mktag", which'll just
re-use these "fsck.*" variables as-is.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-01-05 14:58:29 -08:00
Jonathan Tan
9eb86f41de fsck: do not lazy fetch known non-promisor object
There is a call to has_object_file(), which lazily fetches missing
objects in a partial clone, when the object is known to not be
a promisor object. Change that call to has_object(), which does not do
any lazy fetching.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-06 13:01:03 -07:00
Junio C Hamano
645f63111b Merge branch 'es/get-worktrees-unsort'
API cleanup for get_worktrees()

* es/get-worktrees-unsort:
  worktree: drop get_worktrees() unused 'flags' argument
  worktree: drop get_worktrees() special-purpose sorting option
2020-07-06 22:09:15 -07:00
Eric Sunshine
03f2465bb1 worktree: drop get_worktrees() unused 'flags' argument
get_worktrees() accepts a 'flags' argument, however, there are no
existing flags (the lone flag GWT_SORT_LINKED was recently retired) and
no behavior which can be tweaked. Therefore, drop the 'flags' argument.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-06-22 10:31:15 -07:00
Abhishek Kumar
6da43d937c object: drop parsed_object_pool->commit_count
14ba97f8 (alloc: allow arbitrary repositories for alloc functions,
2018-05-15) introduced parsed_object_pool->commit_count to keep count of
commits per repository and was used to assign commit->index.

However, commit-slab code requires commit->index values to be unique
and a global count would be correct, rather than a per-repo count.

Let's introduce a static counter variable, `parsed_commits_count` to
keep track of parsed commits so far.

As commit_count has no use anymore, let's also drop it from the struct.

Signed-off-by: Abhishek Kumar <abhishekkumar8222@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-06-17 14:37:14 -07:00
Junio C Hamano
d55a4ae71d Merge branch 'ds/multi-pack-verify'
Fix for a copy-and-paste error introduced during 2.20 era.

* ds/multi-pack-verify:
  fsck: use ERROR_MULTI_PACK_INDEX
2020-05-24 19:39:39 -07:00
Derrick Stolee
e68a5272b1 fsck: use ERROR_MULTI_PACK_INDEX
The multi-pack-index was added to the data verified by git-fsck in
ea5ae6c3 "fsck: verify multi-pack-index". This implementation was
based on the implementation for verifying the commit-graph, and a
copy-paste error kept the ERROR_COMMIT_GRAPH flag as the bit set
when an error appears in the multi-pack-index.

Add a new flag, ERROR_MULTI_PACK_INDEX, and use that instead.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-05-19 16:13:22 -07:00
Jeff King
5afc4b1dc6 fsck: only provide oid/type in fsck_error callback
None of the callbacks actually care about having a "struct object";
they're happy with just the oid and type information. So let's give
ourselves more flexibility to avoid having a "struct object" by just
passing the broken-down fields.

Note that the callback already takes a "type" field for the fsck message
type. We'll rename that to "msg_type" (and use "object_type" for the
object type) to make the distinction explicit.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-28 14:05:18 +09:00
Jeff King
82ef89b318 fsck: don't require object structs for display functions
Our printable_type() and describe_object() functions take whole object
structs, but they really only care about the oid and type. Let's take
those individually in order to give our callers more flexibility.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-28 14:05:18 +09:00
Jeff King
733902905d fsck: use oids rather than objects for object_name API
We don't actually care about having object structs; we only need to look
up decorations by oid. Let's accept this more limited form, which will
give our callers more flexibility.

Note that the decoration API we rely on uses object structs itself (even
though it only looks at their oids). We can solve this by switching to
a kh_oid_map (we could also use the hashmap oidmap, but it's more
awkward for the simple case of just storing a void pointer).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-28 14:05:18 +09:00
Jeff King
a59cfb3230 fsck: unify object-name code
Commit 90cf590f53 (fsck: optionally show more helpful info for broken
links, 2016-07-17) added a system for decorating objects with names. The
code is split across builtin/fsck.c (which gives the initial names) and
fsck.c (which adds to the names as it traverses the object graph). This
leads to some duplication, where both sites have near-identical
describe_object() functions (the difference being that the one in
builtin/fsck.c uses a circular array of buffers to allow multiple calls
in a single printf).

Let's provide a unified object_name API for fsck. That lets us drop the
duplication, as well as making the interface boundaries more clear
(which will let us refactor the implementation more in a future patch).

We'll leave describe_object() in builtin/fsck.c as a thin wrapper around
the new API, as it relies on a static global to make its many callers a
bit shorter.

We'll also convert the bare add_decoration() calls in builtin/fsck.c to
put_object_name(). This fixes two minor bugs:

  1. We leak many small strings. add_decoration() has a last-one-wins
     approach: it updates the decoration to the new string and returns
     the old one. But we ignore the return value, leaking the old
     string. This is quite common to trigger, since we look at reflogs:
     the tip of any ref will be described both by looking at the actual
     ref, as well as the latest reflog entry. So we'd always end up
     leaking one of those strings.

  2. The last-one-wins approach gives us lousy names. For instance, we
     first look at all of the refs, and then all of the reflogs. So
     rather than seeing "refs/heads/master", we're likely to overwrite
     it with "HEAD@{12345678}". We're generally better off using the
     first name we find.

     And indeed, the test in t1450 expects this ugly HEAD@{} name. After
     this patch, we've switched to using fsck_put_object_name()'s
     first-one-wins semantics, and we output the more human-friendly
     "refs/tags/julius" (and the test is updated accordingly).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-28 14:05:17 +09:00
Jeff King
d0229abd93 object: convert lookup_object() to use object_id
There are no callers left of lookup_object() that aren't just passing us
the "hash" member of a "struct object_id". Let's take the whole struct,
which gets us closer to removing all raw sha1 variables.  It also
matches the existing conversions of lookup_blob(), etc.

The conversions of callers were done by hand, but they're all mechanical
one-liners.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-20 10:18:09 -07:00
Jeff King
0ebbcf70e6 object: convert lookup_unknown_object() to use object_id
There are no callers left of lookup_unknown_object() that aren't just
passing us the "hash" member of a "struct object_id". Let's take the
whole struct, which gets us closer to removing all raw sha1 variables.
It also matches the existing conversions of lookup_blob(), etc.

The conversions of callers were done by hand, but they're all mechanical
one-liners.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-20 10:06:19 -07:00
Junio C Hamano
ea327760d3 Merge branch 'jk/fsck-doc'
"git fsck --connectivity-only" omits computation necessary to sift
the objects that are not reachable from any of the refs into
unreachable and dangling.  This is now enabled when dangling
objects are requested (which is done by default, but can be
overridden with the "--no-dangling" option).

* jk/fsck-doc:
  fsck: always compute USED flags for unreachable objects
  doc/fsck: clarify --connectivity-only behavior
2019-03-20 15:16:06 +09:00
Jeff King
8d8c2a5aef fsck: always compute USED flags for unreachable objects
The --connectivity-only option avoids opening every object, and instead
just marks reachable objects with a flag and compares this to the set
of all objects. This strategy is discussed in more detail in 3e3f8bd608
(fsck: prepare dummy objects for --connectivity-check, 2017-01-17).

This means that we report _every_ unreachable object as dangling.
Whereas in a full fsck, we'd have actually opened and parsed each of
those unreachable objects, marking their child objects with the USED
flag, to mean "this was mentioned by another object". And thus we can
report only the tip of an unreachable segment of the object graph as
dangling.

You can see this difference with a trivial example:

  tree=$(git hash-object -t tree -w /dev/null)
  one=$(echo one | git commit-tree $tree)
  two=$(echo two | git commit-tree -p $one $tree)

Running `git fsck` will report only $two as dangling, but with
--connectivity-only, both commits (and the tree) are reported. Likewise,
using --lost-found would write all three objects.

We can make --connectivity-only work like the normal case by taking a
separate pass over the unreachable objects, parsing them and marking
objects they refer to as USED. That still avoids parsing any blobs,
though we do pay the cost to access any unreachable commits and trees
(which may or may not be noticeable, depending on how many you have).

If neither --dangling nor --lost-found is in effect, then we can skip
this step entirely, just like we do now. That makes "--connectivity-only
--no-dangling" just as fast as the current "--connectivity-only". I.e.,
we do the correct thing always, but you can still tweak the options to
make it faster if you don't care about dangling objects.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-03-05 22:55:57 +09:00
Junio C Hamano
7589e63648 Merge branch 'nd/the-index-final'
The assumption to work on the single "in-core index" instance has
been reduced from the library-ish part of the codebase.

* nd/the-index-final:
  cache.h: flip NO_THE_INDEX_COMPATIBILITY_MACROS switch
  read-cache.c: remove the_* from index_has_changes()
  merge-recursive.c: remove implicit dependency on the_repository
  merge-recursive.c: remove implicit dependency on the_index
  sha1-name.c: remove implicit dependency on the_index
  read-cache.c: replace update_index_if_able with repo_&
  read-cache.c: kill read_index()
  checkout: avoid the_index when possible
  repository.c: replace hold_locked_index() with repo_hold_locked_index()
  notes-utils.c: remove the_repository references
  grep: use grep_opt->repo instead of explict repo argument
2019-02-06 22:05:23 -08:00
Junio C Hamano
b99a579f8e Merge branch 'sb/more-repo-in-api'
The in-core repository instances are passed through more codepaths.

* sb/more-repo-in-api: (23 commits)
  t/helper/test-repository: celebrate independence from the_repository
  path.h: make REPO_GIT_PATH_FUNC repository agnostic
  commit: prepare free_commit_buffer and release_commit_memory for any repo
  commit-graph: convert remaining functions to handle any repo
  submodule: don't add submodule as odb for push
  submodule: use submodule repos for object lookup
  pretty: prepare format_commit_message to handle arbitrary repositories
  commit: prepare logmsg_reencode to handle arbitrary repositories
  commit: prepare repo_unuse_commit_buffer to handle any repo
  commit: prepare get_commit_buffer to handle any repo
  commit-reach: prepare in_merge_bases[_many] to handle any repo
  commit-reach: prepare get_merge_bases to handle any repo
  commit-reach.c: allow get_merge_bases_many_0 to handle any repo
  commit-reach.c: allow remove_redundant to handle any repo
  commit-reach.c: allow merge_bases_many to handle any repo
  commit-reach.c: allow paint_down_to_common to handle any repo
  commit: allow parse_commit* to handle any repo
  object: parse_object to honor its repository argument
  object-store: prepare has_{sha1, object}_file to handle any repo
  object-store: prepare read_object_file to deal with any repo
  ...
2019-02-05 14:26:09 -08:00
Nguyễn Thái Ngọc Duy
f8adbec9fe cache.h: flip NO_THE_INDEX_COMPATIBILITY_MACROS switch
By default, index compat macros are off from now on, because they
could hide the_index dependency.

Only those in builtin can use it.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-01-24 11:55:06 -08:00
Junio C Hamano
cde555480b Merge branch 'nd/the-index'
More codepaths become aware of working with in-core repository
instance other than the default "the_repository".

* nd/the-index: (22 commits)
  rebase-interactive.c: remove the_repository references
  rerere.c: remove the_repository references
  pack-*.c: remove the_repository references
  pack-check.c: remove the_repository references
  notes-cache.c: remove the_repository references
  line-log.c: remove the_repository reference
  diff-lib.c: remove the_repository references
  delta-islands.c: remove the_repository references
  cache-tree.c: remove the_repository references
  bundle.c: remove the_repository references
  branch.c: remove the_repository reference
  bisect.c: remove the_repository reference
  blame.c: remove implicit dependency the_repository
  sequencer.c: remove implicit dependency on the_repository
  sequencer.c: remove implicit dependency on the_index
  transport.c: remove implicit dependency on the_index
  notes-merge.c: remove implicit dependency the_repository
  notes-merge.c: remove implicit dependency on the_index
  list-objects.c: reduce the_repository references
  list-objects-filter.c: remove implicit dependency on the_index
  ...
2019-01-04 13:33:33 -08:00