Commit Graph

536 Commits

Author SHA1 Message Date
Bradley M. Kuhn
3abd4a67d9 Documentation: stylistically normalize references to Signed-off-by:
Ted reported an old typo in the git-commit.txt and merge-options.txt.
Namely, the phrase "Signed-off-by line" was used without either a
definite nor indefinite article.

Upon examination, it seems that the documentation (including items in
Documentation/, but also option help strings) have been quite
inconsistent on usage when referring to `Signed-off-by`.

First, very few places used a definite or indefinite article with the
phrase "Signed-off-by line", but that was the initial typo that led
to this investigation.  So, normalize using either an indefinite or
definite article consistently.

The original phrasing, in Commit 3f971fc425 (Documentation updates,
2005-08-14), is "Add Signed-off-by line".  Commit 6f855371a5 (Add
--signoff, --check, and long option-names. 2005-12-09) switched to
using "Add `Signed-off-by:` line", but didn't normalize the former
commit to match.  Later commits seem to have cut and pasted from one
or the other, which is likely how the usage became so inconsistent.

Junio stated on the git mailing list in
<xmqqy2k1dfoh.fsf@gitster.c.googlers.com> a preference to leave off
the colon.  Thus, prefer `Signed-off-by` (with backticks) for the
documentation files and Signed-off-by (without backticks) for option
help strings.

Additionally, Junio argued that "trailer" is now the standard term to
refer to `Signed-off-by`, saying that "becomes plenty clear that we
are not talking about any random line in the log message".  As such,
prefer "trailer" over "line" anywhere the former word fits.

However, leave alone those few places in documentation that use
Signed-off-by to refer to the process (rather than the specific
trailer), or in places where mail headers are generally discussed in
comparison with Signed-off-by.

Reported-by: "Theodore Y. Ts'o" <tytso@mit.edu>
Signed-off-by: Bradley M. Kuhn <bkuhn@sfconservancy.org>
Acked-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-10-20 11:57:40 -07:00
Junio C Hamano
0df670bc0b Merge branch 'jt/interpret-branch-name-fallback'
"git status" has trouble showing where it came from by interpreting
reflog entries that recordcertain events, e.g. "checkout @{u}", and
gives a hard/fatal error.  Even though it inherently is impossible
to give a correct answer because the reflog entries lose some
information (e.g. "@{u}" does not record what branch the user was
on hence which branch 'the upstream' needs to be computed, and even
if the record were available, the relationship between branches may
have changed), at least hide the error to allow "status" show its
output.

* jt/interpret-branch-name-fallback:
  wt-status: tolerate dangling marks
  refs: move dwim_ref() to header file
  sha1-name: replace unsigned int with option struct
2020-09-09 13:53:09 -07:00
Junio C Hamano
9c31b19dd0 Merge branch 'pw/rebase-i-more-options'
"git rebase -i" learns a bit more options.

* pw/rebase-i-more-options:
  t3436: do not run git-merge-recursive in dashed form
  rebase: add --reset-author-date
  rebase -i: support --ignore-date
  rebase -i: support --committer-date-is-author-date
  am: stop exporting GIT_COMMITTER_DATE
  rebase -i: add --ignore-whitespace flag
2020-09-03 12:37:01 -07:00
Jonathan Tan
f24c30e0b6 wt-status: tolerate dangling marks
When a user checks out the upstream branch of HEAD, the upstream branch
not being a local branch, and then runs "git status", like this:

  git clone $URL client
  cd client
  git checkout @{u}
  git status

no status is printed, but instead an error message:

  fatal: HEAD does not point to a branch

(This error message when running "git branch" persists even after
checking out other things - it only stops after checking out a branch.)

This is because "git status" reads the reflog when determining the "HEAD
detached" message, and thus attempts to DWIM "@{u}", but that doesn't
work because HEAD no longer points to a branch.

Therefore, when calculating the status of a worktree, tolerate dangling
marks. This is done by adding an additional parameter to
dwim_ref() and repo_dwim_ref().

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-02 14:39:25 -07:00
Phillip Wood
e8cbe2118a am: stop exporting GIT_COMMITTER_DATE
The implementation of --committer-date-is-author-date exports
GIT_COMMITTER_DATE to override the default committer date but does not
reset GIT_COMMITTER_DATE in the environment after creating the commit
so it is set in the environment of any hooks that get run. We're about
to add the same functionality to the sequencer and do not want to have
GIT_COMMITTER_DATE set when running hooks or exec commands so lets
update commit_tree_extended() to take an explicit committer so we
override the default date without setting GIT_COMMITTER_DATE in the
environment.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-17 11:58:37 -07:00
Jeff King
d70a9eb611 strvec: rename struct fields
The "argc" and "argv" names made sense when the struct was argv_array,
but now they're just confusing. Let's rename them to "nr" (which we use
for counts elsewhere) and "v" (which is rather terse, but reads well
when combined with typical variable names like "args.v").

Note that we have to update all of the callers immediately. Playing
tricks with the preprocessor is hard here, because we wouldn't want to
rewrite unrelated tokens.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-30 19:18:06 -07:00
Jeff King
ef8d7ac42a strvec: convert more callers away from argv_array name
We eventually want to drop the argv_array name and just use strvec
consistently. There's no particular reason we have to do it all at once,
or care about interactions between converted and unconverted bits.
Because of our preprocessor compat layer, the names are interchangeable
to the compiler (so even a definition and declaration using different
names is OK).

This patch converts remaining files from the first half of the alphabet,
to keep the diff to a manageable size.

The conversion was done purely mechanically with:

  git ls-files '*.c' '*.h' |
  xargs perl -i -pe '
    s/ARGV_ARRAY/STRVEC/g;
    s/argv_array/strvec/g;
  '

and then selectively staging files with "git add '[abcdefghjkl]*'".
We'll deal with any indentation/style fallouts separately.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-28 15:02:18 -07:00
Junio C Hamano
24ecfdf206 Merge branch 'tb/fix-persistent-shallow' into master
When "fetch.writeCommitGraph" configuration is set in a shallow
repository and a fetch moves the shallow boundary, we wrote out
broken commit-graph files that do not match the reality, which has
been corrected.

* tb/fix-persistent-shallow:
  commit.c: don't persist substituted parents when unshallowing
2020-07-09 14:00:44 -07:00
Taylor Blau
ce16364e89 commit.c: don't persist substituted parents when unshallowing
Since 37b9dcabfc (shallow.c: use '{commit,rollback}_shallow_file',
2020-04-22), Git knows how to reset stat-validity checks for the
$GIT_DIR/shallow file, allowing it to change between a shallow and
non-shallow state in the same process (e.g., in the case of 'git fetch
--unshallow').

However, when $GIT_DIR/shallow changes, Git does not alter or remove any
grafts (nor substituted parents) in memory.

This comes up in a "git fetch --unshallow" with fetch.writeCommitGraph
set to true. Ordinarily in a shallow repository (and before 37b9dcabfc,
even in this case), commit_graph_compatible() would return false,
indicating that the repository should not be used to write a
commit-graphs (since commit-graph files cannot represent a shallow
history). But since 37b9dcabfc, in an --unshallow operation that check
succeeds.

Thus even though the repository isn't shallow any longer (that is, we
have all of the objects), the in-core representation of those objects
still has munged parents at the shallow boundaries.  When the
commit-graph write proceeds, we use the incorrect parentage, producing
wrong results.

There are two ways for a user to work around this: either (1) set
'fetch.writeCommitGraph' to 'false', or (2) drop the commit-graph after
unshallowing.

One way to fix this would be to reset the parsed object pool entirely
(flushing the cache and thus preventing subsequent reads from modifying
their parents) after unshallowing. That would produce a problem when
callers have a now-stale reference to the old pool, and so this patch
implements a different approach. Instead, attach a new bit to the pool,
'substituted_parent', which indicates if the repository *ever* stored a
commit which had its parents modified (i.e., the shallow boundary
prior to unshallowing).

This bit needs to be sticky because all reads subsequent to modifying a
commit's parents are unreliable when unshallowing. Modify the check in
'commit_graph_compatible' to take this bit into account, and correctly
avoid generating commit-graphs in this case, thus solving the bug.

Helped-by: Derrick Stolee <dstolee@microsoft.com>
Helped-by: Jonathan Nieder <jrnieder@gmail.com>
Reported-by: Jay Conrod <jayconrod@google.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-08 16:13:46 -07:00
Abhishek Kumar
c752ad09c4 commit-graph: minimize commit_graph_data_slab access
In an earlier patch, multiple struct acccesses to `graph_pos` and
`generation` were auto-converted to multiple method calls.

Since the values are fixed and commit-slab access costly, we would be
better off with storing the values as a local variable and reusing it.

Signed-off-by: Abhishek Kumar <abhishekkumar8222@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-06-17 14:37:52 -07:00
Abhishek Kumar
c49c82aa4c commit: move members graph_pos, generation to a slab
We remove members `graph_pos` and `generation` from the struct commit.
The default assignments in init_commit_node() are no longer valid,
which is fine as the slab helpers return appropriate default values and
the assignments are removed.

We will replace existing use of commit->generation and commit->graph_pos
by commit_graph_data_slab helpers using
`contrib/coccinelle/commit.cocci'.

Signed-off-by: Abhishek Kumar <abhishekkumar8222@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-06-17 14:37:30 -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
896833b268 Merge branch 'tb/shallow-cleanup'
Code cleanup.

* tb/shallow-cleanup:
  shallow: use struct 'shallow_lock' for additional safety
  shallow.h: document '{commit,rollback}_shallow_file'
  shallow: extract a header file for shallow-related functions
  commit: make 'commit_graft_pos' non-static
2020-05-13 12:19:18 -07:00
Taylor Blau
120ad2b0f1 shallow: extract a header file for shallow-related functions
There are many functions in commit.h that are more related to shallow
repositories than they are to any sort of generic commit machinery.
Likely this began when there were only a few shallow-related functions,
and commit.h seemed a reasonable enough place to put them.

But, now there are a good number of shallow-related functions, and
placing them all in 'commit.h' doesn't make sense.

This patch extracts a 'shallow.h', which takes all of the declarations
from 'commit.h' for functions which already exist in 'shallow.c'. We
will bring the remaining shallow-related functions defined in 'commit.c'
in a subsequent patch.

For now, move only the ones that already are implemented in 'shallow.c',
and update the necessary includes.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-30 14:19:13 -07:00
Taylor Blau
183df649ca commit: make 'commit_graft_pos' non-static
In the next patch, some functions will be moved from 'commit.c' to have
prototypes in a new 'shallow.h' and their implementations in
'shallow.c'.

Three functions in 'commit.c' use 'commit_graft_pos()' (they are
'register_commit_graft()', 'lookup_commit_graft()', and
'unregister_shallow()'). The first two of these will stay in 'commit.c',
but the latter will move to 'shallow.c', and thus needs
'commit_graft_pos' to be non-static.

Prepare for that by making 'commit_graft_pos' non-static so that it can
be called from both 'commit.c' and 'shallow.c'.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-30 14:18:41 -07:00
Junio C Hamano
fb4175b0e4 Merge branch 'at/rebase-fork-point-regression-fix'
The "--fork-point" mode of "git rebase" regressed when the command
was rewritten in C back in 2.20 era, which has been corrected.

* at/rebase-fork-point-regression-fix:
  rebase: --fork-point regression fix
2020-03-26 17:11:21 -07:00
brian m. carlson
42d4e1d112 commit: use expected signature header for SHA-256
The transition plan anticipates that we will allow signatures using
multiple algorithms in a single commit. In order to do so, we need to
use a different header per algorithm so that it will be obvious over
which data to compute the signature.

The transition plan specifies that we should use "gpgsig-sha256", so
wire up the commit code such that it can write and parse the current
algorithm, and it can remove the headers for any algorithm when creating
a new commit. Add tests to ensure that we write using the right header
and that git fsck doesn't reject these commits.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-24 09:33:30 -08:00
Junio C Hamano
9f3f38769d Merge branch 'rs/strbuf-insertstr'
Code clean-up.

* rs/strbuf-insertstr:
  mailinfo: don't insert header prefix for handle_content_type()
  strbuf: add and use strbuf_insertstr()
2020-02-17 13:22:17 -08:00
Junio C Hamano
f08132f889 rebase: --fork-point regression fix
"git rebase --fork-point master" used to work OK, as it internally
called "git merge-base --fork-point" that knew how to handle short
refname and dwim it to the full refname before calling the
underlying get_fork_point() function.

This is no longer true after the command was rewritten in C, as its
internall call made directly to get_fork_point() does not dwim a
short ref.

Move the "dwim the refname argument to the full refname" logic that
is used in "git merge-base" to the underlying get_fork_point()
function, so that the other caller of the function in the
implementation of "git rebase" behaves the same way to fix this
regression.

Signed-off-by: Alex Torok <alext9@gmail.com>
[jc: revamped the fix and used Alex's tests]
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-11 09:59:39 -08:00
René Scharfe
a91cc7fad0 strbuf: add and use strbuf_insertstr()
Add a function for inserting a C string into a strbuf.  Use it
throughout the source to get rid of magic string length constants and
explicit strlen() calls.

Like strbuf_addstr(), implement it as an inline function to avoid the
implicit strlen() calls to cause runtime overhead.

Helped-by: Taylor Blau <me@ttaylorr.com>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-10 09:04:45 -08:00
Hans Jerry Illikainen
54887b4689 gpg-interface: add minTrustLevel as a configuration option
Previously, signature verification for merge and pull operations checked
if the key had a trust-level of either TRUST_NEVER or TRUST_UNDEFINED in
verify_merge_signature().  If that was the case, the process die()d.

The other code paths that did signature verification relied entirely on
the return code from check_commit_signature().  And signatures made with
a good key, irregardless of its trust level, was considered valid by
check_commit_signature().

This difference in behavior might induce users to erroneously assume
that the trust level of a key in their keyring is always considered by
Git, even for operations where it is not (e.g. during a verify-commit or
verify-tag).

The way it worked was by gpg-interface.c storing the result from the
key/signature status *and* the lowest-two trust levels in the `result`
member of the signature_check structure (the last of these status lines
that were encountered got written to `result`).  These are documented in
GPG under the subsection `General status codes` and `Key related`,
respectively [1].

The GPG documentation says the following on the TRUST_ status codes [1]:

    """
    These are several similar status codes:

    - TRUST_UNDEFINED <error_token>
    - TRUST_NEVER     <error_token>
    - TRUST_MARGINAL  [0  [<validation_model>]]
    - TRUST_FULLY     [0  [<validation_model>]]
    - TRUST_ULTIMATE  [0  [<validation_model>]]

    For good signatures one of these status lines are emitted to
    indicate the validity of the key used to create the signature.
    The error token values are currently only emitted by gpgsm.
    """

My interpretation is that the trust level is conceptionally different
from the validity of the key and/or signature.  That seems to also have
been the assumption of the old code in check_signature() where a result
of 'G' (as in GOODSIG) and 'U' (as in TRUST_NEVER or TRUST_UNDEFINED)
were both considered a success.

The two cases where a result of 'U' had special meaning were in
verify_merge_signature() (where this caused git to die()) and in
format_commit_one() (where it affected the output of the %G? format
specifier).

I think it makes sense to refactor the processing of TRUST_ status lines
such that users can configure a minimum trust level that is enforced
globally, rather than have individual parts of git (e.g. merge) do it
themselves (except for a grace period with backward compatibility).

I also think it makes sense to not store the trust level in the same
struct member as the key/signature status.  While the presence of a
TRUST_ status code does imply that the signature is good (see the first
paragraph in the included snippet above), as far as I can tell, the
order of the status lines from GPG isn't well-defined; thus it would
seem plausible that the trust level could be overwritten with the
key/signature status if they were stored in the same member of the
signature_check structure.

This patch introduces a new configuration option: gpg.minTrustLevel.  It
consolidates trust-level verification to gpg-interface.c and adds a new
`trust_level` member to the signature_check structure.

Backward-compatibility is maintained by introducing a special case in
verify_merge_signature() such that if no user-configurable
gpg.minTrustLevel is set, then the old behavior of rejecting
TRUST_UNDEFINED and TRUST_NEVER is enforced.  If, on the other hand,
gpg.minTrustLevel is set, then that value overrides the old behavior.

Similarly, the %G? format specifier will continue show 'U' for
signatures made with a key that has a trust level of TRUST_UNDEFINED or
TRUST_NEVER, even though the 'U' character no longer exist in the
`result` member of the signature_check structure.  A new format
specifier, %GT, is also introduced for users that want to show all
possible trust levels for a signature.

Another approach would have been to simply drop the trust-level
requirement in verify_merge_signature().  This would also have made the
behavior consistent with other parts of git that perform signature
verification.  However, requiring a minimum trust level for signing keys
does seem to have a real-world use-case.  For example, the build system
used by the Qubes OS project currently parses the raw output from
verify-tag in order to assert a minimum trust level for keys used to
sign git tags [2].

[1] https://git.gnupg.org/cgi-bin/gitweb.cgi?p=gnupg.git;a=blob;f=doc/doc/DETAILS;h=bd00006e933ac56719b1edd2478ecd79273eae72;hb=refs/heads/master
[2] 9674c1991d/scripts/verify-git-tag (L43)

Signed-off-by: Hans Jerry Illikainen <hji@dyntopia.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-15 14:06:06 -08:00
Junio C Hamano
0e07c1cd83 Merge branch 'jk/cleanup-object-parsing-and-fsck'
Crufty code and logic accumulated over time around the object
parsing and low-level object access used in "git fsck" have been
cleaned up.

* jk/cleanup-object-parsing-and-fsck: (23 commits)
  fsck: accept an oid instead of a "struct tree" for fsck_tree()
  fsck: accept an oid instead of a "struct commit" for fsck_commit()
  fsck: accept an oid instead of a "struct tag" for fsck_tag()
  fsck: rename vague "oid" local variables
  fsck: don't require an object struct in verify_headers()
  fsck: don't require an object struct for fsck_ident()
  fsck: drop blob struct from fsck_finish()
  fsck: accept an oid instead of a "struct blob" for fsck_blob()
  fsck: don't require an object struct for report()
  fsck: only require an oid for skiplist functions
  fsck: only provide oid/type in fsck_error callback
  fsck: don't require object structs for display functions
  fsck: use oids rather than objects for object_name API
  fsck_describe_object(): build on our get_object_name() primitive
  fsck: unify object-name code
  fsck: require an actual buffer for non-blobs
  fsck: stop checking tag->tagged
  fsck: stop checking commit->parent counts
  fsck: stop checking commit->tree value
  commit, tag: don't set parsed bit for parse failures
  ...
2019-12-01 09:04:28 -08:00
Junio C Hamano
5c8c0a0d78 Merge branch 'pw/post-commit-from-sequencer'
"rebase -i" ceased to run post-commit hook by mistake in an earlier
update, which has been corrected.

* pw/post-commit-from-sequencer:
  sequencer: run post-commit hook
  move run_commit_hook() to libgit and use it there
  sequencer.h fix placement of #endif
  t3404: remove uneeded calls to set_fake_editor
  t3404: set $EDITOR in subshell
  t3404: remove unnecessary subshell
2019-11-10 18:02:12 +09:00
Jeff King
228c78fbd4 commit, tag: don't set parsed bit for parse failures
If we can't parse a commit, then parse_commit() will return an error
code. But it _also_ sets the "parsed" flag, which tells us not to bother
trying to re-parse the object. That means that subsequent parses have no
idea that the information in the struct may be bogus.  I.e., doing this:

  parse_commit(commit);
  ...
  if (parse_commit(commit) < 0)
          die("commit is broken");

will never trigger the die(). The second parse_commit() will see the
"parsed" flag and quietly return success.

There are two obvious ways to fix this:

  1. Stop setting "parsed" until we've successfully parsed.

  2. Keep a second "corrupt" flag to indicate that we saw an error (and
     when the parsed flag is set, return 0/-1 depending on the corrupt
     flag).

This patch does option 1. The obvious downside versus option 2 is that
we might continually re-parse a broken object. But in practice,
corruption like this is rare, and we typically die() or return an error
in the caller. So it's OK not to worry about optimizing for corruption.
And it's much simpler: we don't need to use an extra bit in the object
struct, and callers which check the "parsed" flag don't need to learn
about the corrupt bit, too.

There's no new test here, because this case is already covered in t5318.
Note that we do need to update the expected message there, because we
now detect the problem in the return from "parse_commit()", and not with
a separate check for a NULL tree. In fact, we can now ditch that
explicit tree check entirely, as we're covered robustly by this change
(and the previous recent change to treat a NULL tree as a parse error).

We'll also give tags the same treatment. I don't know offhand of any
cases where the problem can be triggered (it implies somebody ignoring a
parse error earlier in the process), but consistently returning an error
should cause the least surprise.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-28 14:04:49 +09:00
Jeff King
12736d2f02 parse_commit_buffer(): treat lookup_tree() failure as parse error
If parsing a commit yields a valid tree oid, but we've seen that same
oid as a non-tree in the same process, the resulting commit struct will
end up with a NULL tree pointer, but not otherwise report a parsing
failure.

That's perhaps convenient for callers which want to operate on even
partially corrupt commits (e.g., by still looking at the parents). But
it leaves a potential trap for most callers, who now have to manually
check for a NULL tree. Most do not, and it's likely that there are
possible segfaults lurking. I say "possible" because there are many
candidates, and I don't think it's worth following through on
reproducing them when we can just fix them all in one spot. And
certainly we _have_ seen real-world cases, such as the one fixed by
806278dead (commit-graph.c: handle corrupt/missing trees, 2019-09-05).

Note that we can't quite drop the check in the caller added by that
commit yet, as there's some subtlety with repeated parsings (which will
be addressed in a future commit).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-21 11:15:23 +09:00
Jeff King
c78fe00459 parse_commit_buffer(): treat lookup_commit() failure as parse error
While parsing the parents of a commit, if we are able to parse an actual
oid but lookup_commit() fails on it (because we previously saw it in
this process as a different object type), we silently omit the parent
and do not report any error to the caller.

The caller has no way of knowing this happened, because even an empty
parent list is a valid parse result. As a result, it's possible to fool
our "rev-list" connectivity check into accepting a corrupted set of
objects.

There's a test for this case already in t6102, but unfortunately it has
a slight error. It creates a broken commit with a parent line pointing
to a blob, and then checks that rev-list notices the problem in two
cases:

  1. the "lone" case: we traverse the broken commit by itself (here we
     try to actually load the blob from disk and find out that it's not
     a commit)

  2. the "seen" case: we parse the blob earlier in the process, and then
     when calling lookup_commit() we realize immediately that it's not a
     commit

The "seen" variant for this test mistakenly parsed another commit
instead of the blob, meaning that we were actually just testing the
"lone" case again. Changing that reveals the breakage (and shows that
this fixes it).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-21 11:15:23 +09:00
Phillip Wood
49697cb721 move run_commit_hook() to libgit and use it there
This function was declared in commit.h but was implemented in
builtin/commit.c so was not part of libgit. Move it to libgit so we can
use it in the sequencer. This simplifies the implementation of
run_prepare_commit_msg_hook() and will be used in the next commit.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-16 10:30:51 +09:00
Junio C Hamano
80693e3f09 Merge branch 'tb/commit-graph-harden'
The code to parse and use the commit-graph file has been made more
robust against corrupted input.

* tb/commit-graph-harden:
  commit-graph.c: handle corrupt/missing trees
  commit-graph.c: handle commit parsing errors
  t/t5318: introduce failing 'git commit-graph write' tests
2019-10-07 11:32:58 +09:00
Junio C Hamano
21ce0b48f3 Merge branch 'mh/release-commit-memory-fix'
Leakfix.

* mh/release-commit-memory-fix:
  commit: free the right buffer in release_commit_memory
2019-09-30 13:19:25 +09:00
Taylor Blau
806278dead commit-graph.c: handle corrupt/missing trees
Apply similar treatment as in the previous commit to handle an unchecked
call to 'get_commit_tree_oid()'. Previously, a NULL return value from
this function would be immediately dereferenced with '->hash', and then
cause a segfault.

Before dereferencing to access the 'hash' member, check the return value
of 'get_commit_tree_oid()' to make sure that it is not NULL.

To make this check correct, a related change is also needed in
'commit.c', which is to check the return value of 'get_commit_tree'
before taking its address. If 'get_commit_tree' returns NULL, we
encounter an undefined behavior when taking the address of the return
value of 'get_commit_tree' and then taking '->object.oid'. (On my system,
this is memory address 0x8, which is obviously wrong).

Fix this by making sure that 'get_commit_tree' returns something
non-NULL before digging through a structure that is not there, thus
preventing a segfault down the line in the commit graph code.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-09-09 10:55:59 -07:00
Mike Hommey
9784f97321 commit: free the right buffer in release_commit_memory
The index field in the commit object is used to find the buffer
corresponding to that commit in the buffer_slab. Resetting it first
means free_commit_buffer is not going to free the right buffer.

Signed-off-by: Mike Hommey <mh@glandium.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-08-26 10:53:25 -07:00
Junio C Hamano
dea6737bb7 Merge branch 'ds/close-object-store' into maint
The commit-graph file is now part of the "files that the runtime
may keep open file descriptors on, all of which would need to be
closed when done with the object store", and the file descriptor to
an existing commit-graph file now is closed before "gc" finalizes a
new instance to replace it.

* ds/close-object-store:
  packfile: rename close_all_packs to close_object_store
  packfile: close commit-graph in close_all_packs
  commit-graph: use raw_object_store when closing
  commit-graph: extract write_commit_graph_file()
  commit-graph: extract copy_oids_to_commits()
  commit-graph: extract count_distinct_commits()
  commit-graph: extract fill_oids_from_all_packs()
  commit-graph: extract fill_oids_from_commit_hex()
  commit-graph: extract fill_oids_from_packs()
  commit-graph: create write_commit_graph_context
  commit-graph: remove Future Work section
  commit-graph: collapse parameters into flags
  commit-graph: return with errors during write
  commit-graph: fix the_repository reference
2019-07-29 12:38:22 -07:00
Junio C Hamano
a7db4c193d Merge branch 'jk/oidhash'
Code clean-up to remove hardcoded SHA-1 hash from many places.

* jk/oidhash:
  hashmap: convert sha1hash() to oidhash()
  hash.h: move object_id definition from cache.h
  khash: rename oid helper functions
  khash: drop sha1-specific map types
  pack-bitmap: convert khash_sha1 maps into kh_oid_map
  delta-islands: convert island_marks khash to use oids
  khash: rename kh_oid_t to kh_oid_set
  khash: drop broken oid_map typedef
  object: convert create_object() to use object_id
  object: convert internal hash_obj() to object_id
  object: convert lookup_object() to use object_id
  object: convert lookup_unknown_object() to use object_id
  pack-objects: convert locate_object_entry_hash() to object_id
  pack-objects: convert packlist_find() to use object_id
  pack-bitmap-write: convert some helpers to use object_id
  upload-pack: rename a "sha1" variable to "oid"
  describe: fix accidental oid/hash type-punning
2019-07-09 15:25:43 -07:00
Junio C Hamano
e1168940ce Merge branch 'ds/commit-graph-write-refactor'
Renamed from commit-graph-format-v2 and changed scope.

* ds/commit-graph-write-refactor:
  commit-graph: extract write_commit_graph_file()
  commit-graph: extract copy_oids_to_commits()
  commit-graph: extract count_distinct_commits()
  commit-graph: extract fill_oids_from_all_packs()
  commit-graph: extract fill_oids_from_commit_hex()
  commit-graph: extract fill_oids_from_packs()
  commit-graph: create write_commit_graph_context
  commit-graph: remove Future Work section
  commit-graph: collapse parameters into flags
  commit-graph: return with errors during write
  commit-graph: fix the_repository reference
2019-07-09 15:25:36 -07:00
Jeff King
a378509e1c object: convert create_object() to use object_id
There are no callers left of create_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.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-20 10:20:51 -07:00
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
Derrick Stolee
c7944050af commit-graph: fix the_repository reference
The parse_commit_buffer() method takes a repository pointer, so it
should not refer to the_repository anymore.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-05-13 11:52:19 +09:00
Junio C Hamano
ea2dab1abb Merge branch 'tb/unexpected'
Code tightening against a "wrong" object appearing where an object
of a different type is expected, instead of blindly assuming that
the connection between objects are correctly made.

* tb/unexpected:
  rev-list: detect broken root trees
  rev-list: let traversal die when --missing is not in use
  get_commit_tree(): return NULL for broken tree
  list-objects.c: handle unexpected non-tree entries
  list-objects.c: handle unexpected non-blob entries
  t: introduce tests for unexpected object types
  t: move 'hex2oct' into test-lib-functions.sh
2019-05-09 00:37:25 +09:00
Nguyễn Thái Ngọc Duy
301b8c7f40 commit.c: add repo_get_commit_tree()
Remove the implicit dependency on the_repository in this function.
It will be used in sha1-name.c functions when they are updated to take
any 'struct repository'. get_commit_tree() remains as a compat wrapper,
to be slowly replaced later.

Any access to "maybe_tree" field directly will result in _broken_ code
after running through commit.cocci because we can't know what is the
right repository to use.

the_repository would be correct most of the time. But we're relying less
and less on the_repository and that assumption may no longer be
true. The transformation now is more of a poor man replacement for a C++
compiler catching access to private fields.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-04-16 18:56:51 +09:00
Nguyễn Thái Ngọc Duy
a133c40b23 commit.cocci: refactor code, avoid double rewrite
"maybe" pointer in 'struct commit' is tricky because it can be lazily
initialized to take advantage of commit-graph if available. This makes
it not safe to access directly.

This leads to a rule in commit.cocci to rewrite 'x->maybe_tree' to
'get_commit_tree(x)'. But that rule alone could lead to incorrectly
rewrite assignments, e.g. from

    x->maybe_tree = yes

to

    get_commit_tree(x) = yes

Because of this we have a second rule to revert this effect. Szeder
found out that we could do better by performing the assignment rewrite
rule first, then the remaining is read-only access and handled by the
current first rule.

For this to work, we need to transform "x->maybe_tree = y" to something
that does NOT contain "x->maybe_tree" to avoid the original first
rule. This is where set_commit_tree() comes in.

Helped-by: SZEDER Gábor <szeder.dev@gmail.com>
Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-04-16 18:56:51 +09:00
Jeff King
834876630b get_commit_tree(): return NULL for broken tree
Return NULL from 'get_commit_tree()' when a commit's root tree is
corrupt, doesn't exist, or points to an object which is not a tree.

In [1], this situation became a BUG(), but it can certainly occur in
cases which are not a bug in Git, for e.g., if a caller manually crafts
a commit whose tree is corrupt in any of the above ways.

Note that the expect_failure test in t6102 triggers this BUG(), but we
can't flip it to expect_success yet. Solving this problem actually
reveals a second bug.

[1]: 7b8a21dba1 (commit-graph: lazy-load trees for commits, 2018-04-06)

Co-authored-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-04-10 12:59:39 +09:00
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
Stefan Beller
6a7895fd8a commit: prepare free_commit_buffer and release_commit_memory for any repo
Pass the object pool to free_commit_buffer and release_commit_memory,
such that we can eliminate access to 'the_repository'.

Also remove the TODO in release_commit_memory, as commit->util was
removed in 9d2c97016f (commit.h: delete 'util' field in struct commit,
2018-05-19)

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-12-28 10:06:33 -08:00
Junio C Hamano
6d2035ee60 Merge branch 'jk/verify-sig-merge-into-void'
"git merge" and "git pull" that merges into an unborn branch used
to completely ignore "--verify-signatures", which has been
corrected.

* jk/verify-sig-merge-into-void:
  pull: handle --verify-signatures for unborn branch
  merge: handle --verify-signatures for unborn branch
  merge: extract verify_merge_signature() helper
2018-11-18 18:23:54 +09:00
Junio C Hamano
62ca33e02a Merge branch 'ds/reachable-topo-order'
The revision walker machinery learned to take advantage of the
commit generation numbers stored in the commit-graph file.

* ds/reachable-topo-order:
  t6012: make rev-list tests more interesting
  revision.c: generation-based topo-order algorithm
  commit/revisions: bookkeeping before refactoring
  revision.c: begin refactoring --topo-order logic
  test-reach: add rev-list tests
  test-reach: add run_three_modes method
  prio-queue: add 'peek' operation
2018-11-18 18:23:52 +09:00
Stefan Beller
70315373ae commit: prepare repo_unuse_commit_buffer to handle any repo
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-11-14 17:22:40 +09:00
Stefan Beller
07de3fd840 commit: prepare get_commit_buffer to handle any repo
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-11-14 17:22:40 +09:00
Stefan Beller
9e5252abd1 commit: allow parse_commit* to handle any repo
Just like the previous commit, parse_commit and friends are used a lot
and are found in new patches, so we cannot change their signature easily.

Re-introduce these function prefixed with 'repo_' that take a repository
argument and keep the original as a shallow macro.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-11-14 17:22:40 +09:00
Jeff King
edc4d47d54 merge: extract verify_merge_signature() helper
The logic to implement "merge --verify-signatures" is inline in
cmd_merge(), but this site misses some cases. Let's extract the logic
into a function so we can call it from more places.

We'll move it to commit.[ch], since one of the callers (git-pull) is
outside our source file. This function isn't all that general (after
all, its main function is to exit the program) but it's not worth trying
to fix that. The heavy lifting is done by check_commit_signature(), and
our purpose here is just sharing the die() logic. We'll mark it with a
comment to make that clear.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-11-07 10:11:09 +09:00
Derrick Stolee
5284fc5cc9 commit/revisions: bookkeeping before refactoring
There are a few things that need to move around a little before
making a big refactoring in the topo-order logic:

1. We need access to record_author_date() and
   compare_commits_by_author_date() in revision.c. These are used
   currently by sort_in_topological_order() in commit.c.

2. Moving these methods to commit.h requires adding an author_date_slab
   declaration to commit.h. Consumers will need their own implementation.

3. The add_parents_to_list() method in revision.c performs logic
   around the UNINTERESTING flag and other special cases depending
   on the struct rev_info. Allow this method to ignore a NULL 'list'
   parameter, as we will not be populating the list for our walk.
   Also rename the method to the slightly more generic name
   process_parents() to make clear that this method does more than
   add to a list (and no list is required anymore).

Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-11-02 12:14:22 +09:00