rev-list: let traversal die when --missing is not in use
Commit 7c0fe330d5 (rev-list: handle missing tree objects properly,
2018-10-05) taught the traversal machinery used by git-rev-list to
ignore missing trees, so that rev-list could handle them itself.
However, it does so only by checking via oid_object_info_extended() that
the object exists at all. This can miss several classes of errors that
were previously detected by rev-list:
- type mismatches (e.g., we expected a tree but got a blob)
- failure to read the object data (e.g., due to bitrot on disk)
This is especially important because we use "rev-list --objects" as our
connectivity check to admit new objects to the repository, and it will
now miss these cases (though the bitrot one is less important here,
because we'd typically have just hashed and stored the object).
There are a few options to fix this:
1. we could check these properties in rev-list when we do the existence
check. This is probably too expensive in practice (perhaps even for
a type check, but definitely for checking the whole content again,
which implies loading each object into memory twice).
2. teach the traversal machinery to differentiate between a missing
object, and one that could not be loaded as expected. This probably
wouldn't be too hard to detect type mismatches, but detecting bitrot
versus a truly missing object would require deep changes to the
object-loading code.
3. have the traversal machinery communicate the failure to the caller,
so that it can decide how to proceed without re-evaluting the object
itself.
Of those, I think (3) is probably the best path forward. However, this
patch does none of them. In the name of expediently fixing the
regression to a normal "rev-list --objects" that we use for connectivity
checks, this simply restores the pre-7c0fe330d5 behavior of having the
traversal die as soon as it fails to load a tree (when --missing is set
to MA_ERROR, which is the default).
Note that we can't get rid of the object-existence check in
finish_object(), because this also handles blobs (which are not
otherwise checked at all by the traversal code).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
Fix one of the cases described in the previous commit where a tree-entry
that is promised to a blob is in fact a non-blob.
When 'lookup_blob()' returns NULL, it is because Git has cached the
requested object as a non-blob. In this case, prevent a SIGSEGV by
'die()'-ing immediately before attempting to dereference the result.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Call an object's type "unexpected" when the actual type of an object
does not match Git's contextual expectation. For example, a tree entry
whose mode differs from the object's actual type, or a commit's parent
which is not another commit, and so on.
This can manifest itself in various unfortunate ways, including Git
SIGSEGV-ing under specific conditions. Consider the following example:
Git traverses a blob (say, via `git rev-list`), and then tries to read
out a tree-entry which lists that object as something other than a blob.
In this case, `lookup_blob()` will return NULL, and the subsequent
dereference will result in a SIGSEGV.
Introduce tests that present objects of "unexpected" type in the above
fashion to 'git rev-list'. Mark as failures the combinations that are
already broken (i.e., they exhibit the segfault described above). In the
cases that are not broken (i.e., they have NULL-ness checks or similar),
mark these as expecting success.
We might hit an unexpected type in two different ways (imagine we have a
tree entry that claims to be a tree but actually points to a blob):
- when we call lookup_tree(), we might find that we've already seen
the object referenced as a blob, in which case we'd get NULL. We
can exercise this with "git rev-list --objects $blob $tree", which
guarantees that the blob will have been parsed before we look in
the tree. These tests are marked as "seen" in the test script.
- we call lookup_tree() successfully, but when we try to read the
object, we find out it's something else. We construct our tests
such that $blob is not otherwise mentioned in $tree. These tests
are marked as "lone" in the script.
We should check that we behave sensibly in both cases (especially
because it is easy for a malicious actor to provoke one case or the
other).
Co-authored-by: Jeff King <peff@peff.net> 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>
add: error appropriately on repository with no commits
The previous commit made 'git add' abort when given a repository that
doesn't have a commit checked out. However, the output upon failure
isn't appropriate:
% git add repo
warning: adding embedded git repository: repo
hint: You've added another git repository inside your current repository.
hint: [...]
error: unable to index file 'repo/'
fatal: adding files failed
The hint doesn't apply in this case, and the error message doesn't
tell the user why 'repo' couldn't be added to the index.
Provide better output by teaching add_to_index() to error when given a
git directory where HEAD can't be resolved. To avoid the embedded
repository warning and hint, call check_embedded_repo() only after
add_file_to_index() succeeds because, in general, its output doesn't
make sense if adding to the index fails.
Signed-off-by: Kyle Meyer <kyle@kyleam.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When treat_directory() encounters a directory that is not in the index
and DIR_NO_GITLINKS is unset, it calls resolve_gitlink_ref() to decide
if a directory looks like a repository, in which case the directory
won't be traversed. As a result, 'status -uall' and 'ls-files -o'
will show only the directory, even when there are untracked files
within the directory.
For the unusual case where a repository doesn't have a commit checked
out, resolve_gitlink_ref() returns -1 because HEAD cannot be resolved,
and the directory is treated as a normal directory (i.e. traversal
does not stop at the repository boundary). The status and ls-files
commands above list untracked files within the repository rather than
showing only the top-level directory. And if 'git add' is called on a
repository with no commit checked out, any untracked files under the
repository are added as blobs in the top-level project, a behavior
that is unlikely to be what the caller intended.
The above case is a corner case in an already unusual situation of the
working tree containing a repository that is not a tracked submodule,
but we might as well treat anything that looks like a repository
consistently. Loosen the "looks like a repository" criteria in
treat_directory() by replacing resolve_gitlink_ref() with
is_nonbare_repository_dir(), one of the checks that is performed
downstream when resolve_gitlink_ref() is called.
As the required update to t3700-add shows, calling 'git add' on a
repository with no commit checked out will now raise an error. While
this is the desired behavior, note that the output isn't yet
appropriate. The next commit will improve this output.
Signed-off-by: Kyle Meyer <kyle@kyleam.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
submodule: refuse to add repository with no commits
When the path given to 'git submodule add' is an existing repository
that is not in the index, the repository is passed to 'git add'. If
this repository doesn't have a commit checked out, we don't get a
useful result: there is no subproject OID to track, and any untracked
files in the sub-repository are added as blobs in the top-level
repository.
To avoid getting into this state, abort if the path is a repository
that doesn't have a commit checked out. Note that this check must
come before the 'git add --dry-run' check because the next commit will
make 'git add' fail when given a repository that doesn't have a commit
checked out.
Signed-off-by: Kyle Meyer <kyle@kyleam.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
This teaches git-submodule the set-branch subcommand which allows the
branch of a submodule to be set through a porcelain command without
having to manually manipulate the .gitmodules file.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The {apostrophe} was needed at the time of a521845800 ("Documentation:
remove stray backslash in show-branch discussion", 2010-08-20). All
other uses of {apostrophe} were removed in 6cf378f0cb ("docs: stop using
asciidoc no-inline-literal", 2012-04-26).
Unfortunately, the {apostrophe} is rendered literally with Asciidoctor
(at least with 1.5.5-2.0.3). Avoid this by using single-quotes.
Escaping the leading single-quote allows the content to render properly
in AsciiDoc and Asciidoctor.
Signed-off-by: Todd Zullinger <tmz@pobox.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The second paragraph in the CONFIGURATION section intends to emphasize
the word 'must' with bold type. It does so by writing it as *must*, and
this works fine with AsciiDoc. It usually works great with Asciidoctor,
too, but in this particular instance, we have another "*" earlier in the
paragraph. We do escape it, and it is rendered literally just like we
want it to, but Asciidoctor then ends up tripping on the second (or
third) of the asterisks in this paragraph.
Since that asterisk is (part of) a literal example, we can set it in
monospace, by giving it as `*`. Adjust the whole paragraph in this way.
There's lots more monospacing to be done in this document, but since our
main motivation is addressing AsciiDoc/Asciidoctor discrepancies like
this one, let's just convert this one paragraph.
Signed-off-by: Todd Zullinger <tmz@pobox.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git worktree add" used to do a "find an available name with stat
and then mkdir", which is race-prone. This has been fixed by using
mkdir and reacting to EEXIST in a loop.
* ra/t3600-test-path-funcs:
t3600: use helpers to replace test -d/f/e/s <path>
t3600: modernize style
test functions: add function `test_file_not_empty`
"git rebase" uses the refs/rewritten/ hierarchy to store its
intermediate states, which inherently makes the hierarchy per
worktree, but it didn't quite work well.
* nd/rewritten-ref-is-per-worktree:
Make sure refs/rewritten/ is per-worktree
files-backend.c: reduce duplication in add_per_worktree_entries_to_dir()
files-backend.c: factor out per-worktree code in loose_fill_ref_dir()
When the "clean" filter can reduce the size of a huge file in the
working tree down to a small "token" (a la Git LFS), there is no
point in allocating a huge scratch area upfront, but the buffer is
sized based on the original file size. The convert mechanism now
allocates very minimum and reallocates as it receives the output
from the clean filter process.
* jh/resize-convert-scratch-buffer:
convert: avoid malloc of original file size
MSVC: include compat/win32/path-utils.h for MSVC, too, for real_path()
A path such as 'c:/somepath/submodule/../.git/modules/submodule' wasn't
resolved correctly any more, because the *nix variant of offset_1st_component
is used instead of the Win32 specific version.
Regression was introduced in commit 1cadad6f6 when mingw_offset_1st_component
was moved from mingw.c which is included by msvc.c to a separate file. Then,
the new file "compat/win32/path-utils.h" was only included for the __CYGWIN__
and __MINGW32__ cases in git-compat-util.h, the case for _MSC_VER was missing.
Signed-off-by: Sven Strickroth <email@cs-ware.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 6956f858f6 (notes: implement helpers needed for note copying during
rewrite, 2010-03-12), we introduced a test case that verifies that the
config setting `notes.rewriteRef` can be overridden via the environment
variable `GIT_NOTES_REWRITE_REF`.
Back when it was introduced, it relied on a side effect of an earlier
test case that configured `core.noteRef` to point to `refs/notes/other`.
In 908a320363 (t3301: modernize style, 2014-11-12), this side effect was
removed.
The test case *still* passed, but for the wrong reason: we no longer
overrode the rewrite ref, but there simply was nothing to rewrite
anymore, as the overridden notes ref was "modernized" away.
Let's let that test case pass for the correct reason again.
To make sure of that, let's change the idea of the original test case:
it configured `notes.rewriteRef` to point to the actual notes ref,
forced that to be ignored and then verified that the notes were *not*
rewritten.
By turning that idea upside down (configure the `notes.rewriteRef` to
another notes ref, override it via the environment variable to force the
notes to be copied, and then verify that the notes *were* rewritten), we
make it much harder for that test case to pass for the wrong reason.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use oideq() instead of !oidcmp(), as it is more idiomatic, and might
give the compiler more opportunities to optimize.
Patch generated with 'contrib/coccinelle/free.cocci' and Coccinelle
v1.0.7 (previous Coccinelle versions don't notice this).
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com> Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use the macro FREE_AND_NULL to release memory allocated for
'head_name' and clear its pointer.
Patch generated with 'contrib/coccinelle/free.cocci' and Coccinelle
v1.0.7 (previous Coccinelle versions don't notice this).
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com> Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
blame: default to HEAD in a bare repo when no start commit is given
When 'git blame' is invoked without specifying the commit to start
blaming from, it starts from the given file's state in the work tree.
However, when invoked in a bare repository without a start commit,
then there is no work tree state to start from, and it dies with the
following error message:
$ git rev-parse --is-bare-repository
true
$ git blame file.c
fatal: this operation must be run in a work tree
This is misleading, because it implies that 'git blame' doesn't work
in bare repositories at all, but it does, in fact, work just fine when
it is given a commit to start from.
We could improve the error message, of course, but let's just default
to HEAD in a bare repository instead, as most likely that is what the
user wanted anyway (if they wanted to start from an other commit, then
they would have specified that in the first place).
'git annotate' is just a thin wrapper around 'git blame', so in the
same situation it printed the same misleading error message, and this
patch fixes it, too.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
struct stat_data and struct cache_time both use unsigned ints for all
their members. However the format string for 'git ls-files --debug'
currently uses %d for formatting these numbers. This means that we
potentially print these values incorrectly if they are greater than
INT_MAX.
This has been the case since the --debug option was introduced in 'git
ls-files' in 8497421715 ("ls-files: learn a debugging dump format",
2010-07-31).
Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The chance of a repository being corrupted due to a "gc" has nothing
to do with whether or not that "gc" was invoked via "gc --auto", but
whether there's other concurrent operations happening.
This is already noted earlier in the paragraph, so there's no reason
to suggest this here. The user can infer from the rest of the
documentation that "gc" will run automatically unless gc.auto=0 is
set, and we shouldn't confuse the issue by implying that "gc --auto"
is somehow more prone to produce corruption than a normal "gc".
Well, it is in the sense that a blocking "gc" would stop you from
doing anything else in *that* particular terminal window, but users
are likely to have another window, or to be worried about how
concurrent "gc" on a server might cause corruption.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
gc docs: clarify that "gc" doesn't throw away referenced objects
Amend the "NOTES" section to fix up wording that's been with us since 3ffb58be0a ("doc/git-gc: add a note about what is collected",
2008-04-23).
I can't remember when/where anymore (I think Freenode #Git), but at
some point I was having a conversation with someone who was convinced
that "gc" would prune things only referenced by e.g. refs/pull/*, and
pointed to this section as proof.
It turned out that they'd read the "branches and tags" wording here
and thought just refs/{heads,tags}/* and refs/remotes/* etc. would be
kept, which is what we enumerate explicitly.
So let's say "other refs", even though just above we say "objects that
are referenced anywhere in your repository".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Amend the "PACKFILE OPTIMIZATION" section in "fast-import" to explain
that simply running "git gc --aggressive" after a "fast-import" should
properly optimize the repository. This is simpler and more effective
than the existing "repack" advice (which I'm keeping as it helps
explain things) because it e.g. also packs the newly imported refs.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The existing "gc --aggressive" docs come just short of recommending to
users that they run it regularly. I've personally talked to many users
who've taken these docs as an advice to use this option, and have,
usually it's (mostly) a waste of time.
So let's clarify what it really does, and let the user draw their own
conclusions.
Let's also clarify the "The effects [...] are persistent" to
paraphrase a brief version of Jeff King's explanation at [1].
gc docs: note how --aggressive impacts --window & --depth
Since 07e7dbf0db (gc: default aggressive depth to 50, 2016-08-11) we
somewhat confusingly use the same depth under --aggressive as we do by
default.
As noted in that commit that makes sense, it was wrong to make more
depth the default for "aggressive", and thus save disk space at the
expense of runtime performance, which is usually the opposite of
someone who'd like "aggressive gc" wants.
But that's left us with a mostly-redundant configuration variable, so
let's clearly note in its documentation that it doesn't change the
default.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the AsciiDoc formatting so that an example of "gc --auto" isn't
rendered as "git-gc(1) --auto", but as "git gc --auto". This is
consistent with the rest of the links and command examples in this
documentation.
The formatting I'm changing was initially introduced in d5d5d7b641 ("gc: automatically write commit-graph files", 2018-06-27).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Re-flow the "gc.*" section in "config". A previous commit moved this
over from the "gc" docs, but tried to keep as many of the lines
identical to benefit from diff's move detection.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
gc docs: include the "gc.*" section from "config" in "gc"
Rather than duplicating the documentation for the various "gc" options
let's include the "gc" docs from git-config. They were mostly better
already, and now we don't have the same docs in two places with subtly
different wording.
In the cases where the git-gc(1) docs were saying something the "gc"
docs in git-config(1) didn't cover move the relevant section over to
the git-config(1) docs.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When all of x/a, x/b, and x/c have moved to z/a, z/b, and z/c on one
branch, there is a question about whether x/d added on a different
branch should remain at x/d or appear at z/d when the two branches are
merged. There are different possible viewpoints here:
A) The file was placed at x/d; it's unrelated to the other files in
x/ so it doesn't matter that all the files from x/ moved to z/ on
one branch; x/d should still remain at x/d.
B) x/d is related to the other files in x/, and x/ was renamed to z/;
therefore x/d should be moved to z/d.
Since there was no ability to detect directory renames prior to
git-2.18, users experienced (A) regardless of context. Choice (B) was
implemented in git-2.18, with no option to go back to (A), and has been
in use since. However, one user reported that the merge results did not
match their expectations, making the change of default problematic,
especially since there was no notice printed when directory rename
detection moved files.
Note that there is also a third possibility here:
C) There are different answers depending on the context and content
that cannot be determined by git, so this is a conflict. Use a
higher stage in the index to record the conflict and notify the
user of the potential issue instead of silently selecting a
resolution for them.
Add an option for users to specify their preference for whether to use
directory rename detection, and default to (C). Even when directory
rename detection is on, add notice messages about files moved into new
directories.
As a sidenote, x/d did not have to be a new file here; it could have
already existed at some other path and been renamed to x/d, with
directory rename detection just renaming it again to z/d. Thus, it's
not just new files, but also a modification to all rename types (normal
renames, rename/add, rename/delete, rename/rename(1to1),
rename/rename(1to2), and rename/rename(2to1)).
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-recursive: track information associated with directory renames
Directory rename detection previously silently applied. In order to
allow printing information about paths that changed or printing a
conflict notification (and only doing so near other potential conflict
messages associated with the paths), save this information inside the
rename struct for later use. A subsequent patch will make use of the
additional information.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-recursive: switch from (oid,mode) pairs to a diff_filespec
There was a significant inconsistency in the various parts of the API
used in merge-recursive; many places used a pair of (oid, mode) to track
file version/contents, while other parts used a diff_filespec (which
have an oid and mode embedded in it). This inconsistency caused lots of
places to need to pack and unpack data to call into other functions.
This has been the subject of some past cleanups (see e.g. commit 0270a07ad0b2 ("merge-recursive: remove final remaining caller of
merge_file_one()", 2018-09-19)), but let's just remove the underlying
mess altogether by switching to use diff_filespec.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-recursive: track branch where rename occurred in rename struct
We previously tracked the branch associated with a rename in a separate
field in rename_conflict_info, but since it is directly associated with
the rename it makes more sense to move it into the rename struct.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-recursive: remove ren[12]_other fields from rename_conflict_info
The ren1_other and ren2_other fields were synthesized from information
in ren1->src_entry and ren2->src_entry. Since we already have the
necessary information in ren1 and ren2, just use those.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The rename_conflict_info struct used both a pair and a stage_data which
were taken from a rename struct. Just use the original rename struct.
This will also allow us to start making other simplifications to the
code.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-recursive: move some struct declarations together
These structs are related and reference each other, so move them
together to make it easier for folks to determine what they hold and
what their purpose is.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-recursive: rename locals 'o' and 'a' to 'obuf' and 'abuf'
Since we want to replace oid,mode pairs with a single diff_filespec,
we will soon want to be able to use the names 'o', 'a', and 'b' for
the three different file versions. Rename some local variables in
blob_unchanged() that would otherwise conflict.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-recursive: rename diff_filespec 'one' to 'o'
In the previous commit, we noted that several places throughout merge
recursive both had a reason to use 'o'; some for a merge_options struct,
and others for a diff_filespec struct. Some places had both, forcing
one of the two to be renamed, though the choice was inconsistent. Now
that the merge_options struct has been renamed to 'opt' everywhere, we
can replace the few places that used 'one' for the diff_filespec to 'o'.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-recursive: rename merge_options argument from 'o' to 'opt'
The name 'o' was used for the merge_options struct pointer taken by many
functions, but in a few places it was named 'opt'. Several functions
that didn't need merge_options instead used 'o' for a diff_filespec
argument or local. Some functions needed both an inconsistently either
renamed the merge_options to 'opt' or the diff_filespec to 'one'. I
want to remove the weird split in the codebase between using a
diff_filespec and a pair of (oid,mode) values in favor of using a
diff_filespec everywhere, but that dramatically increases the number of
cases where we want to use 'o' as a diff_filespec. Rename the
merge_options argument to 'opt' to make room.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use 'unsigned short' for mode, like diff_filespec does
struct diff_filespec defines mode to be an 'unsigned short'. Several
other places in the API which we'd like to interact with using a
diff_filespec used a plain unsigned (or unsigned int). This caused
problems when taking addresses, so switch to unsigned short.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The helper 'hex2oct' is used to convert base-16 encoded data into a
base-8 binary form, and is useful for preparing data for commands that
accept input in a binary format, such as 'git hash-object', via
'printf'.
This helper is defined identically in three separate places throughout
't'. Move the definition to test-lib-function.sh, so that it can be used
in new test suites, and its definition is not redundant.
This will likewise make our job easier in the subsequent commit, which
also uses 'hex2oct'.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
progress: assemble percentage and counters in a strbuf before printing
The following patches in this series want to handle the progress bar's
title and changing parts (i.e. the counter and the optional percentage
and throughput combined) differently, and need to know the length
of the changing parts of the previously displayed progress bar.
To prepare for those changes assemble the changing parts in a separate
strbuf kept in 'struct progress' before printing.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Ever since the progress infrastructure was introduced in 96a02f8f6d
(common progress display support, 2007-04-18), display_progress() has
returned an int, telling callers whether it updated the progress bar
or not. However, this is:
- useless, because over the last dozen years there has never been a
single caller that cared about that return value.
- not quite true, because it doesn't print a progress bar when
running in the background, yet it returns 1; see 85cb8906f0
(progress: no progress in background, 2015-04-13).
The related display_throughput() function returned void already upon
its introduction in cf84d51c43 (add throughput to progress display,
2007-10-30).
Let's make display_progress() return void, too. While doing so
several return statements in display() become unnecessary, remove
them.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
ci: fix AsciiDoc/Asciidoctor stderr check in the documentation build job
In 'ci/test-documentation.sh' we save the standard error of 'make
doc', and, in an attempt to make sure that neither AsciiDoc nor
Asciidoctor printed any warnings, we check the emptiness of the
resulting file with '! test -s stderr.log'. This check has never
actually worked, because in our 'ci/*' build scripts we rely on 'set
-e' aborting the build job when a command exits with error, and,
unfortunately, the combination of the two doesn't work as intended.
According to POSIX [1]:
"The -e setting shall be ignored when executing [...] a pipeline
beginning with the ! reserved word" [2]
Watch and learn:
$ echo unexpected >file
$ ( set -e; ! test -s file ; echo "should not reach this" ) ; echo $?
should not reach this
0
This is why we haven't noticed the warnings from Asciidoctor that were
fixed in the first patches of this patch series, though some of them
were already there in the build of v2.18.0-rc0 [3].
Check the emptiness of that file with 'test ! -s' instead, which works
properly with 'set -e':
$ ( set -e; test ! -s file ; echo "should not reach this" ) ; echo $?
1
Furthermore, dump the contents of that file to the log for our
convenience, so if it were to unexpectedly end up being non-empty,
then we wouldn't have to scroll through all that long build log
looking for warnings, but could see them right away near the end of
the log.
Note that we are only really interested in the standard error of
AsciiDoc and Asciidoctor, but by saving the stderr of 'make doc' we
also save any error output from the make rules. Currently there is
only one such line: we build the docs with Asciidoctor right after a
'make clean', meaning that 'make USE_ASCIIDOCTOR=1 doc' always starts
with running 'GIT-VERSION-GEN', which in turn prints the version to
stderr. A 'sed' command was supposed to remove this version line to
prevent it from triggering that (previously defunct) emptiness check,
but, unfortunately, this command doesn't work as intended, either,
because it leaves the file to be checked intact, but that defunct
emptiness check hid this issue, too... Furthermore, in the near
future there will be an other line on stderr, because commit 9a71722b4d (Doc: auto-detect changed build flags, 2019-03-17) in the
currently cooking branch 'ma/doc-diff-doc-vs-doctor-comparison' will
print "* new asciidoc flags" at the beginning of both 'make doc'
invokations.
Extend that 'sed' command to remove this line, too, wrap it in a
helper function so the output of both 'make doc' is filtered the same
way, and change its invokation to actually write the logfile to be
checked.
[2] POSIX doesn't discuss the meaning of '! cmd' in case of simple
commands, but it defines that "A pipeline is a sequence of one or
more commands separated by the control operator '|'", so
apparently a simple command is considered as pipeline as well.
The recent release of Asciidoctor v2.0.0 broke our documentation
build job on Travis CI, where we 'gem install asciidoctor', which
always brings us the latest and (supposedly) greatest. Alas, we are
not ready for that just yet, because it removed support for DocBook
4.5, and we have been requiring that particular DocBook version to
build 'user-manual.xml' with Asciidoctor, resulting in:
ASCIIDOC user-manual.xml
asciidoctor: FAILED: missing converter for backend 'docbook45'. Processing aborted.
Use --trace for backtrace
make[1]: *** [user-manual.xml] Error 1
Unfortunately, we can't simply switch to DocBook 5 right away, as
doing so leads to validation errors from 'xmlto', and working around
those leads to yet another errors... [1]
So let's stick with Asciidoctor v1.5.8 (latest stable release before
v2.0.0) in our documentation build job on Travis CI for now, until we
figure out how to deal with the fallout from Asciidoctor v2.0.0.
Since commit ef0cc1df90f6b ("send-email: also pick up cc addresses from
-by trailers") in git version 2.20, git send-email adds to cc list
addresses from all *-by lines. As a side effect a line with
'-Signed-off-by' is now also added to cc. This makes send-email pick
lines from patches that remove patch files from the git repo. This is
common in the Buildroot project that often removes (and adds) patch
files that have 'Signed-off-by' in their patch description part.
Consider only *-by lines that start with [a-z] (case insensitive) to
avoid unrelated addresses in cc.
Cc: Joe Perches <joe@perches.com> Signed-off-by: Baruch Siach <baruch@tkos.co.il> Acked-by: Rasmus Villemoes <rv@rasmusvillemoes.dk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
revision: use a prio_queue to hold rewritten parents
This patch fixes a quadratic list insertion in rewrite_one() when
pathspec limiting is combined with --parents. What happens is something
like this:
1. We see that some commit X touches the path, so we try to rewrite
its parents.
2. rewrite_one() loops forever, rewriting parents, until it finds a
relevant parent (or hits the root and decides there are none). The
heavy lifting is done by process_parent(), which uses
try_to_simplify_commit() to drop parents.
3. process_parent() puts any intermediate parents into the
&revs->commits list, inserting by commit date as usual.
So if commit X is recent, and then there's a large chunk of history that
doesn't touch the path, we may add a lot of commits to &revs->commits.
And insertion by commit date is O(n) in the worst case, making the whole
thing quadratic.
We tried to deal with this long ago in fce87ae538 (Fix quadratic
performance in rewrite_one., 2008-07-12). In that scheme, we cache the
oldest commit in the list; if the new commit to be added is older, we
can start our linear traversal there. This often works well in practice
because parents are older than their descendants, and thus we tend to
add older and older commits as we traverse.
But this isn't guaranteed, and in fact there's a simple case where it is
not: merges. Imagine we look at the first parent of a merge and see a
very old commit (let's say 3 years old). And on the second parent, as we
go back 3 years in history, we might have many commits. That one
first-parent commit has polluted our oldest-commit cache; it will remain
the oldest while we traverse a huge chunk of history, during which we
have to fall back to the slow, linear method of adding to the list.
Naively, one might imagine that instead of caching the oldest commit,
we'd start at the last-added one. But that just makes some cases faster
while making others slower (and indeed, while it made a real-world test
case much faster, it does quite poorly in the perf test include here).
Fundamentally, these are just heuristics; our worst case is still
quadratic, and some cases will approach that.
Instead, let's use a data structure with better worst-case performance.
Swapping out revs->commits for something else would have repercussions
all over the code base, but we can take advantage of one fact: for the
rewrite_one() case, nobody actually needs to see those commits in
revs->commits until we've finished generating the whole list.
That leaves us with two obvious options:
1. We can generate the list _unordered_, which should be O(n), and
then sort it afterwards, which would be O(n log n) total. This is
"sort-after" below.
2. We can insert the commits into a separate data structure, like a
priority queue. This is "prio-queue" below.
I expected that sort-after would be the fastest (since it saves us the
extra step of copying the items into the linked list), but surprisingly
the prio-queue seems to be a bit faster.
Here are timings for the new p0001.6 for all three techniques across a
few repositories, as compared to master:
- the cache-list tweak does improve the bad case for llvm-project.git
that started my digging into this problem. But it performs terribly
on linux.git, barely helping at all.
- the sort-after and prio-queue techniques work well. They approach
the timing for running without --parents at all, which is what you'd
expect (see below for more data).
- prio-queue just barely outperforms sort-after. As I said, I'm not
really sure why this is the case, but it is. You can see it even
more prominently in this real-world case on llvm-project.git:
where prio-queue routinely outperforms sort-after by about 7%. One
guess is that the prio-queue may just be more efficient because it
uses a compact array.
There are three new perf tests:
- "rev-list --parents" gives us a baseline for running with --parents.
This isn't sped up meaningfully here, because the bad case is
triggered only with simplification. But it's good to make sure we
don't screw it up (now, or in the future).
- "rev-list -- dummy" gives us a baseline for just traversing with
pathspec limiting. This gives a lower bound for the next test (and
it's also a good thing for us to be checking in general for
regressions, since we don't seem to have any existing tests).
- "rev-list --parents -- dummy" shows off the problem (and our fix)
Here are the timings for those three on llvm-project.git, before and
after the fix:
Changes in the first two are basically noise, and you can see we
approach our lower bound in the final one.
Note that we can't fully get rid of the list argument from
process_parents(). Other callers do have lists, and it would be hard to
convert them. They also don't seem to have this problem (probably
because they actually remove items from the list as they loop, meaning
it doesn't grow so large in the first place). So this basically just
drops the "cache_ptr" parameter (which was used only by the one caller
we're fixing here) and replaces it with a prio_queue. Callers are free
to use either data structure, depending on what they're prepared to
handle.
Reported-by: Björn Pettersson A <bjorn.a.pettersson@ericsson.com> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a parent blob already has chunks queued up for blaming, dropping
the blob at the end of one blame step will cause it to get reloaded
right away, doubling the amount of I/O and unpacking when processing a
linear history.
Keeping such parent blobs in memory seems like a reasonable optimization
that should incur additional memory pressure mostly when processing the
merges from old branches.
Signed-off-by: David Kastrup <dak@gnu.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The new command "git switch" is added to avoid the confusion of
one-command-do-all "git checkout" for new users. They are also helpful
to avoid ambiguation context.
For these reasons, promote it everywhere possible. This includes
documentation, suggestions/advice from other commands...
The "Checking out files" progress line in unpack-trees.c is also updated
to "Updating files" to be neutral to both git-checkout and git-switch.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Completion support for --guess could be made better. If no --detach is
given, we should only provide a list of refs/heads/* and dwim ones,
not the entire ref space. But I still can't penetrate that
__git_refs() function yet.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Switching and creating branches always involves knowing the
<start-point> to begin the new branch from. Sometimes, people want to
create a new branch that does not have any commits yet; --orphan is a
flag to allow that.
--orphan overrides the default of HEAD for <start-point> instead causing
us to start from an empty history with all tracked files removed from
the index and working tree. The use of --orphan is incompatible with
specifying a <start-point>.
A note on the implementation. An alternative is just create a dummy
commit in-core with empty tree and switch to it. But there's a chance
the commit's SHA-1 may end up somewhere permanent like reflog. It's best
to make sure "commit" pointer is NULL to avoid it.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Unless you know what you're doing, switching to another branch to do
something then switching back could be confusing. Worse, you may even
forget that you're in the middle of something. By the time you realize,
you may have done a ton of work and it gets harder to go back.
A new option --ignore-in-progress was considered but dropped because it
was not exactly clear what should happen. Sometimes you can switch away
and get back safely and resume the operation. Sometimes not. And the
git-checkout behavior is automatically clear merge/revert/cherry-pick,
which makes it a bit even more confusing [1].
We may revisit and add this option in the future. But for now play it
safe and not allow it (you can't even skip this check with --force). The
user is suggested to cancel the operation by themselves (and hopefully
they do consider the consequences, not blindly type the command), or to
create a separate worktree instead of switching. The third option is
the good old "git checkout", but it's not mentioned.
switch: no worktree status unless real branch switch happens
When we switch from one branch to another, it makes sense to show a
summary of local changes since there could be conflicts, or some files
left modified.... When switch is used solely for creating a new
branch (and "switch" to the same commit) or detaching, we don't really
need to show anything.
"git checkout" does it anyway for historical reasons. But we can start
with a clean slate with switch and don't have to.
This essentially reverts fa655d8411 (checkout: optimize "git checkout
-b <new_branch>" - 2018-08-16) and make it default for switch,
but also for -B and --detach. Users of big repos are encouraged to
move to switch.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
switch: implicit dwim, use --no-guess to disable it
This is already the default in git-checkout. The real change in here is
just minor cleanup. The main excuse is to explain why dwim is kept default.
Contrary to detach mode that is easy to get into and confusing to get
back out. Automatically creating a tracking branch often does not kick
in as often (you would need a branch of the same name on a remote). And
since the branch creation is reported clearly, the user should be able
to undo/delete it if it's unwanted.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git checkout" automatically detaches branches and --detach is not
that useful (--no-detach is more likely). But for "switch", you
may want to use it more often once you're used to detached HEAD. This
of course adds -d to git-checkout but it does not harm (yet?) to do it.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git checkout <commit>" will checkout the commit in question and
detach HEAD from the current branch. It is naturally a right thing to
do once you get git references. But detached HEAD is a scary concept
to new users because we show a lot of warnings and stuff, and it could
be hard to get out of (until you know better).
To keep switch a bit more friendly to new users, we only allow
entering detached HEAD mode when --detach is given. "git
switch" must take a branch (unless you create a new branch,
then of course switch can take any commit-ish)
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git checkout" can be executed without any arguments. What it does is
not exactly great: it switches from HEAD to HEAD and shows worktree
modification as a side effect.
Make switch reject this case. Just use "git status" if you want
that side effect. For switch, you have to either
- really switch a branch
- (explicitly) detach from the current branch
- create a new branch
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
This command is about switching branch (or creating a new one) and
should not accept pathspec. This helps simplify ambiguation
handling. The other two ("git checkout" and "git restore") of
course do accept pathspec as before.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
--discard-changes is a better name than --force for this option since
it's what really happens. --force is turned to an alias for
--discard-changes. But it's meant to be an alias for potentially more
force options in the future.
Side note. It's not obvious from the patch but --discard-changes also
affects submodules if --recurse-submodules is used. The knob to force
updating submodules is hidden behind unpack-trees.c
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The shortcut of these options do not make much sense when used with
switch. And their descriptions are also tied to checkout. Move -b/-B
to cmd_checkout() and new -c/-C with the same functionality in
cmd_switch_branch()
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
checkout: split part of it to new command 'switch'
"git checkout" doing too many things is a source of confusion for many
users (and it even bites old timers sometimes). To remedy that, the
command will be split into two new ones: switch and restore. The good
old "git checkout" command is still here and will be until all (or most
of users) are sick of it.
See the new man page for the final design of switch. The actual
implementation though is still pretty much the same as "git checkout"
and not completely aligned with the man page. Following patches will
adjust their behavior to match the man page.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is a preparation step for introducing new commands that do parts
of what checkout does. There will be two new commands, one is about
switching branches, detaching HEAD... one about checking out
paths. These share the a subset of command line options. The rest of
command line options are separate.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
checkout: move 'confict_style' and 'dwim_..' to checkout_opts
These local variables are referenced by struct option[]. This struct
will soon be broken down, moved away and we can't rely on local
variables anymore. Move these two to struct checkout_opts in
preparation for that.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
"opts" will soon be moved out of cmd_checkout(). To keep changes in
that patch smaller, convert "opts" to a pointer and keep the real
thing behind "real_opts".
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The include list becomes very long and frankly a bit unorganized. With
the exception of builtin.h, cache.h or git-compat-util.h which have to
come first, keep the rest sorted.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
checkout: inform the user when removing branch state
After a successful switch, if a merge, cherry-pick or revert is ongoing,
it is canceled. This behavior has been with us from the very early
beginning, soon after git-merge was created but never actually
documented [1]. It may be a good idea to be transparent and tell the
user if some operation is canceled.
I consider this a better way of telling the user than just adding a
sentence or two in git-checkout.txt, which will be mostly ignored
anyway.
PS. Originally I wanted to print more details like
warning: cancelling an in-progress merge from <SHA-1>
which may allow some level of undo if the user wants to. But that seems
a lot more work. Perhaps it can be improved later if people still want
that.
[1] ... and I will try not to argue whether it is a sensible behavior.
There is some more discussion here if people are interested:
CACsJy8Axa5WsLSjiscjnxVK6jQHkfs-gH959=YtUvQkWriAk5w@mail.gmail.com
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
checkout: advice how to get out of detached HEAD mode
Detached HEAD mode is considered dangerous and confusing for newcomers
and we print a big block of warning how to move forward. But we should
also suggest the user the way to get out of it if they get into detached
HEAD by mistake.
While at there, I also suggest how to turn the advice off. This is
another thing I find annoying with advices and should be dealt with in a
more generic way. But that may require some refactoring in advice.c
first.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>