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18583 commits

Author SHA1 Message Date
Matheus Tavares
45bde58ef8 grep: demonstrate bug with textconv attributes and submodules
In some circumstances, "git grep --textconv --recurse-submodules"
ignores the textconv attributes from the submodules and erroneously
applies the attributes defined in the superproject on the submodules'
files. The textconv cache is also saved on the superproject, even for
submodule objects.

A fix for these problems will probably require at least three changes:

- Some textconv and attributes functions (as well as their callees) will
  have to be adjusted to work with arbitrary repositories. Note that
  "fill_textconv()", for example, already receives a "struct repository"
  but it writes the textconv cache using "write_loose_object()", which
  implicitly works on "the_repository".

- grep.c functions will have to call textconv/userdiff routines passing
  the "repo" field from "struct grep_source" instead of the one from
  "struct grep_opt". The latter always points to "the_repository" on
  "git grep" executions (see its initialization in builtin/grep.c), but
  the former points to the correct repository that each source (an
  object, file, or buffer) comes from.

- "userdiff_find_by_path()" might need to use a different attributes
  stack for each repository it works on or reset its internal static
  stack when the repository is changed throughout the calls.

For now, let's add some tests to demonstrate these problems, and also
update a NEEDSWORK comment in grep.h that mentions this bug to reference
the added tests.

Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-29 13:19:38 -07:00
Taylor Blau
6d08b9d4ca builtin/repack.c: make largest pack preferred
When repacking into a geometric series and writing a multi-pack bitmap,
it is beneficial to have the largest resulting pack be the preferred
object source in the bitmap's MIDX, since selecting the large packs can
lead to fewer broken delta chains and better compression.

Teach 'git repack' to identify this pack and pass it to the MIDX write
machinery in order to mark it as preferred.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 21:20:56 -07:00
Taylor Blau
1d89d88d37 builtin/repack.c: support writing a MIDX while repacking
Teach `git repack` a new `--write-midx` option for callers that wish to
persist a multi-pack index in their repository while repacking.

There are two existing alternatives to this new flag, but they don't
cover our particular use-case. These alternatives are:

  - Call 'git multi-pack-index write' after running 'git repack', or

  - Set 'GIT_TEST_MULTI_PACK_INDEX=1' in your environment when running
    'git repack'.

The former works, but introduces a gap in bitmap coverage between
repacking and writing a new MIDX (since the repack may have deleted a
pack included in the existing MIDX, invalidating it altogether).

Setting the 'GIT_TEST_' environment variable is obviously unsupported.
In fact, even if it were supported officially, it still wouldn't work,
because it generates the MIDX *after* redundant packs have been dropped,
leading to the same issue as above.

Introduce a new option which eliminates this race by teaching `git
repack` to generate the MIDX at the critical point: after the new packs
have been written and moved into place, but before the redundant packs
have been removed.

This option is compatible with `git repack`'s '--bitmap' option (it
changes the interpretation to be: "write a bitmap corresponding to the
MIDX after one has been generated").

There is a little bit of additional noise in the patch below to avoid
repeating ourselves when selecting which packs to delete. Instead of a
single loop as before (where we iterate over 'existing_packs', decide if
a pack is worth deleting, and if so, delete it), we have two loops (the
first where we decide which ones are worth deleting, and the second
where we actually do the deleting). This makes it so we have a single
check we can make consistently when (1) telling the MIDX which packs we
want to exclude, and (2) actually unlinking the redundant packs.

There is also a tiny change to short-circuit the body of
write_midx_included_packs() when no packs remain in the case of an empty
repository. The MIDX code does not handle this, so avoid trying to
generate a MIDX covering zero packs in the first place.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 21:20:56 -07:00
Taylor Blau
08944d1c22 midx: preliminary support for --refs-snapshot
To figure out which commits we can write a bitmap for, the multi-pack
index/bitmap code does a reachability traversal, marking any commit
which can be found in the MIDX as eligible to receive a bitmap.

This approach will cause a problem when multi-pack bitmaps are able to
be generated from `git repack`, since the reference tips can change
during the repack. Even though we ignore commits that don't exist in
the MIDX (when doing a scan of the ref tips), it's possible that a
commit in the MIDX reaches something that isn't.

This can happen when a multi-pack index contains some pack which refers
to loose objects (e.g., if a pack was pushed after starting the repack
but before generating the MIDX which depends on an object which is
stored as loose in the repository, and by definition isn't included in
the multi-pack index).

By taking a snapshot of the references before we start repacking, we can
close that race window. In the above scenario (where we have a packed
object pointing at a loose one), we'll either (a) take a snapshot of the
references before seeing the packed one, or (b) take it after, at which
point we can guarantee that the loose object will be packed and included
in the MIDX.

This patch does just that. It writes a temporary "reference snapshot",
which is a list of OIDs that are at the ref tips before writing a
multi-pack bitmap. References that are "preferred" (i.e,. are a suffix
of at least one value of the 'pack.preferBitmapTips' configuration) are
marked with a special '+'.

The format is simple: one line per commit at each tip, with an optional
'+' at the beginning (for preferred references, as described above).

When provided, the reference snapshot is used to drive bitmap selection
instead of the MIDX code doing its own traversal. When it isn't
provided, the usual traversal takes place instead.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 21:20:56 -07:00
Taylor Blau
6fb22ca463 builtin/multi-pack-index.c: support --stdin-packs mode
To power a new `--write-midx` mode, `git repack` will want to write a
multi-pack index containing a certain set of packs in the repository.

This new option will be used by `git repack` to write a MIDX which
contains only the packs which will survive after the repack (that is, it
will exclude any packs which are about to be deleted).

This patch effectively exposes the function implemented in the previous
commit via the `git multi-pack-index` builtin. An alternative approach
would have been to call that function from the `git repack` builtin
directly, but this introduces awkward problems around closing and
reopening the object store, so the MIDX will be written out-of-process.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 21:20:55 -07:00
Junio C Hamano
bb1677fc29 Merge branch 'jk/reduce-malloc-in-v2-servers'
Code cleanup to limit memory consumption and tighten protocol
message parsing.

* jk/reduce-malloc-in-v2-servers:
  ls-refs: reject unknown arguments
  serve: reject commands used as capabilities
  serve: reject bogus v2 "command=ls-refs=foo"
  docs/protocol-v2: clarify some ls-refs ref-prefix details
  ls-refs: ignore very long ref-prefix counts
  serve: drop "keys" strvec
  serve: provide "receive" function for session-id capability
  serve: provide "receive" function for object-format capability
  serve: add "receive" method for v2 capabilities table
  serve: return capability "value" from get_capability()
  serve: rename is_command() to parse_command()
2021-09-28 13:06:53 -07:00
Derrick Stolee
6579e788c0 advice: update message to suggest '--sparse'
The previous changes modified the behavior of 'git add', 'git rm', and
'git mv' to not adjust paths outside the sparse-checkout cone, even if
they exist in the working tree and their cache entries lack the
SKIP_WORKTREE bit. The intention is to warn users that they are doing
something potentially dangerous. The '--sparse' option was added to each
command to allow careful users the same ability they had before.

To improve the discoverability of this new functionality, add a message
to advice.updateSparsePath that mentions the existence of the option.

The previous set of changes also modified the purpose of this message to
include possibly a list of paths instead of only a list of pathspecs.
Make the warning message more clear about this new behavior.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 10:31:02 -07:00
Derrick Stolee
93d2c16041 mv: refuse to move sparse paths
Since cmd_mv() does not operate on cache entries and instead directly
checks the filesystem, we can only use path_in_sparse_checkout() as a
mechanism for seeing if a path is sparse or not. Be sure to skip
returning a failure if '-k' is specified.

To ensure that the advice around sparse paths is the only reason a move
failed, be sure to check this as the very last thing before inserting
into the src_for_dst list.

The tests cover a variety of cases such as whether the target is tracked
or untracked, and whether the source or destination are in or outside of
the sparse-checkout definition.

Helped-by: Matheus Tavares Bernardino <matheus.bernardino@usp.br>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 10:31:02 -07:00
Derrick Stolee
d7c4415e55 rm: skip sparse paths with missing SKIP_WORKTREE
If a path does not match the sparse-checkout cone but is somehow missing
the SKIP_WORKTREE bit, then 'git rm' currently succeeds in removing the
file. One reason a user might be in this situation is a merge conflict
outside of the sparse-checkout cone. Removing such a file might be
problematic for users who are not sure what they are doing.

Add a check to path_in_sparse_checkout() when 'git rm' is checking if a
path should be considered for deletion. Of course, this check is ignored
if the '--sparse' option is specified, allowing users who accept the
risks to continue with the removal.

This also removes a confusing behavior where a user asks for a directory
to be removed, but only the entries that are within the sparse-checkout
definition are removed. Now, 'git rm <dir>' will fail without '--sparse'
and will succeed in removing all contained paths with '--sparse'.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 10:31:02 -07:00
Derrick Stolee
f9786f9b85 rm: add --sparse option
As we did previously in 'git add', add a '--sparse' option to 'git rm'
that allows modifying paths outside of the sparse-checkout definition.
The existing checks in 'git rm' are restricted to tracked files that
have the SKIP_WORKTREE bit in the current index. Future changes will
cause 'git rm' to reject removing paths outside of the sparse-checkout
definition, even if they are untracked or do not have the SKIP_WORKTREE
bit.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 10:31:02 -07:00
Derrick Stolee
61d450f049 add: update --renormalize to skip sparse paths
We added checks for path_in_sparse_checkout() to portions of 'git add'
that add warnings and prevent stagins a modification, but we skipped the
--renormalize mode. Update renormalize_tracked_files() to ignore cache
entries whose path is outside of the sparse-checkout cone (unless
--sparse is provided). Add a test in t3705.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 10:31:02 -07:00
Derrick Stolee
63b60b3add add: update --chmod to skip sparse paths
We added checks for path_in_sparse_checkout() to portions of 'git add'
that add warnings and prevent staging a modification, but we skipped the
--chmod mode. Update chmod_pathspec() to ignore cache entries whose path
is outside of the sparse-checkout cone (unless --sparse is provided).
Add a test in t3705.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 10:31:02 -07:00
Derrick Stolee
0299a69694 add: implement the --sparse option
We previously modified 'git add' to refuse updating index entries
outside of the sparse-checkout cone. This is justified to prevent users
from accidentally getting into a confusing state when Git removes those
files from the working tree at some later point.

Unfortunately, this caused some workflows that were previously possible
to become impossible, especially around merge conflicts outside of the
sparse-checkout cone. These were documented in tests within t1092.

We now re-enable these workflows using a new '--sparse' option to 'git
add'. This allows users to signal "Yes, I do know what I'm doing with
these files," and accept the consequences of the files leaving the
worktree later.

We delay updating the advice message until implementing a similar option
in 'git rm' and 'git mv'.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 10:31:02 -07:00
Derrick Stolee
49fdd51a23 add: skip tracked paths outside sparse-checkout cone
When 'git add' adds a tracked file that is outside of the
sparse-checkout cone, it checks the SKIP_WORKTREE bit to see if the file
exists outside of the sparse-checkout cone. This is usually correct,
except in the case of a merge conflict outside of the cone.

Modify add_pathspec_matched_against_index() to be more careful about
paths by checking the sparse-checkout patterns in addition to the
SKIP_WORKTREE bit. This causes 'git add' to no longer allow files
outside of the cone that removed the SKIP_WORKTREE bit due to a merge
conflict.

With only this change, users will only be able to add the file after
adding the file to the sparse-checkout cone. A later change will allow
users to force adding even though the file is outside of the
sparse-checkout cone.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 10:31:02 -07:00
Derrick Stolee
105e8b014b add: fail when adding an untracked sparse file
The add_files() method in builtin/add.c takes a set of untracked files
that are being added by the input pathspec and inserts them into the
index. If these files are outside of the sparse-checkout cone, then they
gain the SKIP_WORKTREE bit at some point. However, this was not checked
before inserting into the index, so these files are added even though we
want to avoid modifying the index outside of the sparse-checkout cone.

Add a check within add_files() for these files and write the advice
about files outside of the sparse-checkout cone.

This behavior change modifies some existing tests within t1092. These
tests intended to document how a user could interact with the existing
behavior in place. Many of these tests need to be marked as expecting
failure. A future change will allow these tests to pass by adding a flag
to 'git add' that allows users to modify index entries outside of the
sparse-checkout cone.

The 'submodule handling' test is intended to document what happens to
directories that contain a submodule when the sparse index is enabled.
It is not trying to say that users should be able to add submodules
outside of the sparse-checkout cone, so that test can be modified to
avoid that operation.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 10:31:02 -07:00
Derrick Stolee
edd2cd345f t1092: behavior for adding sparse files
Add some tests to demonstrate the current behavior around adding files
outside of the sparse-checkout cone. Currently, untracked files are
handled differently from tracked files. A future change will make these
cases be handled the same way.

Further expand checking that a failed 'git add' does not stage changes
to the index.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 10:31:02 -07:00
Lénaïc Huard
670e597399 maintenance: fix test t7900-maintenance.sh
Commit b681b191 introduced the support of systemd timers for git
maintenance.
A test is leveraging the `systemd-analyze verify` utility to verify the
correctness of the systemd unit files generated by git.

But on some systems, although the `systemd-analyze` tool is installed
and supports the `verify` subcommand, it fails with some permission
errors.

So, instead of only checking if the `verify` subcommand exists, a more
reliable way of detecting whether `systemd-analyze verify` can be used
is to try to use it.

The SYSTEMD_ANALYZE prerequisite is now trying to run `systemd-analyze
verify` on a systemd unit file which is shipped by systemd itself.
We can reasonably think that, on systemd hosts, this file is present and
valid.

Signed-off-by: Lénaïc Huard <lenaic@lhuard.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 16:06:59 -07:00
Ævar Arnfjörð Bjarmason
f69a6e4f07 *.h: move some *_INIT to designated initializers
Move various *_INIT macros to use designated initializers. This helps
readability. I've only picked those leftover macros that were not
touched by another in-flight series of mine which changed others, but
also how initialization was done.

In the case of SUBMODULE_ALTERNATE_SETUP_INIT I've left an explicit
initialization of "error_mode", even though
SUBMODULE_ALTERNATE_ERROR_IGNORE itself is defined as "0". Let's not
peek under the hood and assume that enum fields we know the value of
will stay at "0".

The change to "TESTSUITE_INIT" in "t/helper/test-run-command.c" was
part of an earlier on-list version[1] of c90be786da (test-tool
run-command: fix flip-flop init pattern, 2021-09-11).

1. https://lore.kernel.org/git/patch-1.1-0aa4523ab6e-20210909T130849Z-avarab@gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 14:48:00 -07:00
Ævar Arnfjörð Bjarmason
608cfd31cf *.h _INIT macros: don't specify fields equal to 0
Change the initialization of "struct strbuf" changed in
cbc0f81d96 (strbuf: use designated initializers in STRBUF_INIT,
2017-07-10) to omit specifying "alloc" and "len", as we do with other
"alloc" and "len" (or "nr") in similar structs.

Let's likewise omit the explicit initialization of all fields in the
"struct ipc_client_connect_option" struct added in
59c7b88198 (simple-ipc: add win32 implementation, 2021-03-15).

Do the same for a few other initializers, e.g. STRVEC_INIT and
CACHE_DEF_INIT.

Finally, start incrementally changing the same pattern in
"t/helper/test-run-command.c". This change was part of an earlier
on-list version[1] of c90be786da (test-tool run-command: fix
flip-flop init pattern, 2021-09-11).

1. https://lore.kernel.org/git/patch-1.1-0aa4523ab6e-20210909T130849Z-avarab@gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 14:47:59 -07:00
Elijah Newren
56d06fe4aa unpack-trees: avoid nuking untracked dir in way of locally deleted file
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 13:38:37 -07:00
Elijah Newren
1fdd51aa13 unpack-trees: avoid nuking untracked dir in way of unmerged file
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 13:38:37 -07:00
Elijah Newren
480d3d6bf9 Change unpack_trees' 'reset' flag into an enum
Traditionally, unpack_trees_options->reset was used to signal that it
was okay to delete any untracked files in the way.  This was used by
`git read-tree --reset`, but then started appearing in other places as
well.  However, many of the other uses should not be deleting untracked
files in the way.  Change this value to an enum so that a value of 1
(i.e. "true") can be split into two:
   UNPACK_RESET_PROTECT_UNTRACKED,
   UNPACK_RESET_OVERWRITE_UNTRACKED
In order to catch accidental misuses (i.e. where folks call it the way
they traditionally used to), define the special enum value of
   UNPACK_RESET_INVALID = 1
which will trigger a BUG().

Modify existing callers so that
   read-tree --reset
   reset --hard
   checkout --force
continue using the UNPACK_RESET_OVERWRITE_UNTRACKED logic, while other
callers, including
   am
   checkout without --force
   stash  (though currently dead code; reset always had a value of 0)
   numerous callers from rebase/sequencer to reset_head()
will use the new UNPACK_RESET_PROTECT_UNTRACKED value.

Also, note that it has been reported that 'git checkout <treeish>
<pathspec>' currently also allows overwriting untracked files[1].  That
case should also be fixed, but it does not use unpack_trees() and thus
is outside the scope of the current changes.

[1] https://lore.kernel.org/git/15dad590-087e-5a48-9238-5d2826950506@gmail.com/

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 13:38:37 -07:00
Elijah Newren
1b5f37334a Remove ignored files by default when they are in the way
Change several commands to remove ignored files by default when they are
in the way.  Since some commands (checkout, merge) take a
--no-overwrite-ignore option to allow the user to configure this, and it
may make sense to add that option to more commands (and in the case of
merge, actually plumb that configuration option through to more of the
backends than just the fast-forwarding special case), add little
comments about where such flags would be used.

Incidentally, this fixes a test failure in t7112.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 13:38:37 -07:00
Elijah Newren
491a7575f1 read-tree, merge-recursive: overwrite ignored files by default
This fixes a long-standing patchwork of ignored files handling in
read-tree and merge-recursive, called out and suggested by Junio long
ago.  Quoting from commit dcf0c16ef1 ("core.excludesfile clean-up"
2007-11-16):

    git-read-tree takes --exclude-per-directory=<gitignore>,
    not because the flexibility was needed.  Again, this was
    because the option predates the standardization of the ignore
    files.

    ...

    On the other hand, I think it makes perfect sense to fix
    git-read-tree, git-merge-recursive and git-clean to follow the
    same rule as other commands.  I do not think of a valid use case
    to give an exclude-per-directory that is nonstandard to
    read-tree command, outside a "negative" test in the t1004 test
    script.

    This patch is the first step to untangle this mess.

    The next step would be to teach read-tree, merge-recursive and
    clean (in C) to use setup_standard_excludes().

History shows each of these were partially or fully fixed:

  * clean was taught the new trick in 1617adc7a0 ("Teach git clean to
    use setup_standard_excludes()", 2007-11-14).

  * read-tree was primarily used by checkout & merge scripts.  checkout
    and merge later became builtins and were both fixed to use the new
    setup_standard_excludes() handling in fc001b526c ("checkout,merge:
    loosen overwriting untracked file check based on info/exclude",
    2011-11-27).  So the primary users were fixed, though read-tree
    itself was not.

  * merge-recursive has now been replaced as the default merge backend
    by merge-ort.  merge-ort fixed this by using
    setup_standard_excludes() starting early in its implementation; see
    commit 6681ce5cf6 ("merge-ort: add implementation of checkout()",
    2020-12-13), largely due to its design depending on checkout() and
    thus being influenced by the checkout code.  However,
    merge-recursive itself was not fixed here, in part because its
    design meant it had difficulty differentiating between untracked
    files, ignored files, leftover tracked files that haven't been
    removed yet due to order of processing files, and files written by
    itself due to collisions).

Make the conversion more complete by now handling read-tree and
handling at least the unpack_trees() portion of merge-recursive.  While
merge-recursive is on its way out, fixing the unpack_trees() portion is
easy and facilitates some of the later changes in this series.  Note
that fixing read-tree makes the --exclude-per-directory option to
read-tree useless, so we remove it from the documentation (though we
continue to accept it if passed).

The read-tree changes happen to fix a bug in t1013.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 13:38:37 -07:00
Jeff King
1763334caf ref-filter: stop setting FILTER_REFS_INCLUDE_BROKEN
Of the ref-filter callers, for-each-ref and git-branch both set the
INCLUDE_BROKEN flag (but git-tag does not, which is a weird
inconsistency).  But now that GIT_REF_PARANOIA is on by default, that
produces almost the same outcome for all three.

The one exception is that GIT_REF_PARANOIA will omit dangling symrefs.
That's a better behavior for these tools, as they would never include
such a symref in the main output anyway (they can't, as it doesn't point
to an object). Instead they issue a warning to stderr. But that warning
is somewhat useless; a dangling symref is a perfectly reasonable thing
to have in your repository, and is not a sign of corruption. It's much
friendlier to just quietly ignore it.

And in terms of robustness, the warning gains us little. It does not
impact the exit code of either tool. So while the warning _might_ clue
in a user that they have an unexpected broken symref, it would not help
any kind of scripted use.

This patch converts for-each-ref and git-branch to stop using the
INCLUDE_BROKEN flag. That gives them more reasonable behavior, and
harmonizes them with git-tag.

We have to change one test to adapt to the situation. t1430 tries to
trigger all of the REF_ISBROKEN behaviors from the underlying ref code.
It uses for-each-ref to do so (because there isn't any other mechanism).
That will no longer issue a warning about the symref which points to an
invalid name, as it's considered dangling (and we can instead be sure
that it's _not_ mentioned on stderr). Note that we do still complain
about the illegally named "broken..symref"; its problem is not that it's
dangling, but the name of the symref itself is illegal.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 12:36:45 -07:00
Jeff King
968f12fdac refs: turn on GIT_REF_PARANOIA by default
The original point of the GIT_REF_PARANOIA flag was to include broken
refs in iterations, so that possibly-destructive operations would not
silently ignore them (and would generally instead try to operate on the
oids and fail when the objects could not be accessed).

We already turned this on by default for some dangerous operations, like
"repack -ad" (where missing a reachability tip would mean dropping the
associated history). But it was not on for general use, even though it
could easily result in the spreading of corruption (e.g., imagine
cloning a repository which simply omits some of its refs because
their objects are missing; the result quietly succeeds even though you
did not clone everything!).

This patch turns on GIT_REF_PARANOIA by default. So a clone as mentioned
above would actually fail (upload-pack tells us about the broken ref,
and when we ask for the objects, pack-objects fails to deliver them).
This may be inconvenient when working with a corrupted repository, but:

  - we are better off to err on the side of complaining about
    corruption, and then provide mechanisms for explicitly loosening
    safety.

  - this is only one type of corruption anyway. If we are missing any
    other objects in the history that _aren't_ ref tips, then we'd
    behave similarly (happily show the ref, but then barf when we
    started traversing).

We retain the GIT_REF_PARANOIA variable, but simply default it to "1"
instead of "0". That gives the user an escape hatch for loosening this
when working with a corrupt repository. It won't work across a remote
connection to upload-pack (because we can't necessarily set environment
variables on the remote), but there the client has other options (e.g.,
choosing which refs to fetch).

As a bonus, this also makes ref iteration faster in general (because we
don't have to call has_object_file() for each ref), though probably not
noticeably so in the general case. In a repo with a million refs, it
shaved a few hundred milliseconds off of upload-pack's advertisement;
that's noticeable, but most repos are not nearly that large.

The possible downside here is that any operation which iterates refs but
doesn't ever open their objects may now quietly claim to have X when the
object is corrupted (e.g., "git rev-list new-branch --not --all" will
treat a broken ref as uninteresting). But again, that's not really any
different than corruption below the ref level. We might have
refs/heads/old-branch as non-corrupt, but we are not actively checking
that we have the entire reachable history. Or the pointed-to object
could even be corrupted on-disk (but our "do we have it" check would
still succeed). In that sense, this is merely bringing ref-corruption in
line with general object corruption.

One alternative implementation would be to actually check for broken
refs, and then _immediately die_ if we see any. That would cause the
"rev-list --not --all" case above to abort immediately. But in many ways
that's the worst of all worlds:

  - it still spends time looking up the objects an extra time

  - it still doesn't catch corruption below the ref level

  - it's even more inconvenient; with the current implementation of
    GIT_REF_PARANOIA for something like upload-pack, we can make
    the advertisement and let the client choose a non-broken piece of
    history. If we bail as soon as we see a broken ref, they cannot even
    see the advertisement.

The test changes here show some of the fallout. A non-destructive "git
repack -adk" now fails by default (but we can override it). Deleting a
broken ref now actually tells the hooks the correct "before" state,
rather than a confusing null oid.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 12:36:45 -07:00
Jeff King
6d751be4b6 refs: omit dangling symrefs when using GIT_REF_PARANOIA
Dangling symrefs aren't actually a corruption problem. It's perfectly
fine for refs/remotes/origin/HEAD to point to an unborn branch. And in
particular, if you are trying to establish reachability, a symref that
points nowhere doesn't matter either way. Any ref it could point to will
be examined during the rest of the traversal.

It's possible that a symref pointing nowhere _could_ be a sign that the
ref it was meant to point to was deleted accidentally (e.g., via
corruption). But there is no particular reason to think that is true for
any given case, and in the meantime, GIT_REF_PARANOIA kicking in
automatically for some operations means they'll fail unnecessarily.

So let's loosen it just a bit. The new test in t5312 shows off an
example that is safe, but currently fails (and no longer does after this
patch).

Note that we don't do anything if the caller explicitly asked for
DO_FOR_EACH_INCLUDE_BROKEN. In that case they may be looking for
dangling symrefs themselves, and setting GIT_REF_PARANOIA should not
_loosen_ things from what the caller asked for.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 12:36:45 -07:00
Jeff King
5b062e1f79 t5312: be more assertive about command failure
When repacking or pruning in a corrupted repository, our tests in t5312
argue that it is OK to complete the operation or bail, as long as we
don't actually delete the objects pointed to by the corruption.

This isn't a wrong line of reasoning, but the tests are a bit permissive
by using test_might_fail. The fact is that we _do_ bail currently, and
if we ever stopped doing so, that would be worthy of a human
investigating. So let's switch these to test_must_fail.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 12:36:45 -07:00
Jeff King
078eecbcbe t5312: test non-destructive repack
In t5312, we create a state with a broken ref, and then make sure that
destructive repacks don't silently ignore the breakage (where a
destructive repack is one that might drop objects). But we don't check
the behavior of non-destructive repacks at all (i.e., ones where we'd
keep unreachable objects).

So let's add a test to confirm the current behavior, which is that
they are allowed (i.e., ignoring the breakage and considering any
objects it points to as unreachable). This may change in the future, but
we'd like for the test suite to alert us to that fact.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 12:36:45 -07:00
Jeff King
f805844676 t5312: create bogus ref as necessary
Some tests in t5312 create an illegally-named ref, and then see how
various operations handle it. But between those operations, we also do
some more setup (e.g., repacking), and we are subtly depending on how
those setup steps react to the illegal ref.

To future-proof us against those behaviors changing, let's instead
create and clean up our bogus ref on demand in the tests that need it.

This has two small extra advantages:

 - the tests are more stand-alone; we do not need an extra test to clean
   up the ref before moving on to other parts of the script

 - the creation and cleanup is together in one helper function. Because
   these depend on touching the refs in the filesystem directly, they
   may need to be tweaked for a world with alternate backends (they have
   not been noticed so far in the reftable work because with a non-file
   backend the tests don't fail; they simply become uninteresting noops
   because the broken ref isn't read at all).

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 12:36:44 -07:00
Jeff King
2ac0cbc9b0 t5312: drop "verbose" helper
t5312 has several uses of the "verbose" helper, as described in
8ad1652418 (t5304: use helper to report failure of "test foo = bar",
2014-10-10). Back then the "-x" trace option for tests was new, and was
not as pleasant to use (e.g., some tests failed under "-x", we did not
support BASH_XTRACEFD, etc).

These days it is clear that "-x" is the preferred way to get extra
output, and we don't need to mark up individual tests. Let's get rid of
the uses of "verbose" here, as one step toward eradicating it totally.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 12:36:44 -07:00
Jeff King
da5e0c6a00 t5600: provide detached HEAD for corruption failures
When checking how git-clone behaves when it fails, we stimulate some
failures by trying to do a clone from a local repository whose objects
have been removed. Because these clones use local optimizations, there's
a subtle dependency in how the corruption is handled on the sending
side.

If upload-pack does not show us the broken refs (which it does not
currently), then we see only HEAD (which is itself broken), and clone
that as a detached HEAD. When we try to write the ref, we notice that we
never got the object and bail.

But if upload-pack _does_ show us the broken refs (which it may in a
future patch), then we'll realize that HEAD is a symref and just write
that. You'd think we'd fail when writing out the refs themselves, but we
don't; we do a bulk write and skip the connectivity check because of our
--local optimizations. For the non-bare case, we do notice the problem
when we try to checkout. But for a bare repository, we unexpectedly
complete the clone successfully!

At first glance this may seem like a bug. But the whole point of those
local optimizations is to give up some safety for speed. If you want to
be careful, you should be using "--no-local", which would notice that
the pack did not transfer sufficient objects. We could do that in these
tests, but part of the point is for them to fail at specific moments
(and indeed, we have a later test that checks for transport failure).

However, we can make this less subtle and future-proof it against
changes on the upload-pack side by just having an explicit detached
HEAD in the corrupted repo. Now we'll fail as expected during the ref
write if any ref _or_ HEAD is corrupt, whether we're --bare or not.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 12:36:44 -07:00
Jeff King
e9de7a52a5 t5516: don't use HEAD ref for invalid ref-deletion tests
A few tests in t5516 want to assert that we can delete a corrupted ref
whose pointed-to object is missing. They do so by using the "main"
branch, which is also pointed to by HEAD.

This does work, but only because of a subtle assumption about the
implementation. We do not block the deletion because of the invalid ref,
but we _also_ do not notice that the deleted branch is pointed to by
HEAD. And so the safety rule of "do not allow HEAD to be deleted in a
non-bare repository" does not kick in, and the test passes.

Let's instead use a non-HEAD branch. That still tests what we care about
here (deleting a corrupt ref), but without implicitly depending on our
failure to notice that we're deleting HEAD. That will future proof the
test against that behavior changing.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 12:36:44 -07:00
Jeff King
b4724242fa t7900: clean up some more broken refs
The "incremental-repack task" test replaces the object directory with a
known state. As a result, some of our refs point to objects that are not
included in that state.

Commit 3cf5f221be (t7900: clean up some broken refs, 2021-01-19) cleaned
up some of those (that were causing warnings to stderr from the
maintenance process). But there are a few more that were missed. These
aren't hurting anything for now, but it's certainly an unexpected state
to leave the test repository in, and it will become a problem if repack
ever gets more picky about broken refs.

Let's clean up those additional refs (which are all in refs/remotes,
with nothing there that isn't broken), and add an extra "for-each-ref"
call to assert that we've got everything.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 12:36:44 -07:00
Andrzej Hunt
44d2aec6e8 connect: also update offset for features without values
parse_feature_value() takes an offset, and uses it to seek past the
point in features_list that we've already seen. However if the feature
being searched for does not specify a value, the offset is not
updated. Therefore if we call parse_feature_value() in a loop on a
value-less feature, we'll keep on parsing the same feature over and over
again. This usually isn't an issue: there's no point in using
next_server_feature_value() to search for repeated instances of the same
capability unless that capability typically specifies a value - but a
broken server could send a response that omits the value for a feature
even when we are expecting a value.

Therefore we add an offset update calculation for the no-value case,
which helps ensure that loops using next_server_feature_value() will
always terminate.

next_server_feature_value(), and the offset calculation, were first
added in 2.28 in 2c6a403d96 (connect: add function to parse multiple
v1 capability values, 2020-05-25).

Thanks to Peff for authoring the test.

Co-authored-by: Jeff King <peff@peff.net>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 10:34:41 -07:00
Derrick Stolee
ca267aee15 t3705: test that 'sparse_entry' is unstaged
The tests in t3705-add-sparse-checkout.sh check to see how 'git add'
behaves with paths outside the sparse-checkout definition. These
currently check to see if a given warning is present but not that the
index is not updated with the sparse entries. Add a new
'test_sparse_entry_unstaged' helper to be sure 'git add' is behaving
correctly.

We need to modify setup_sparse_entry to actually commit the sparse_entry
file so it exists at HEAD and as an entry in the index, but its exact
contents are not staged in the index.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-24 11:43:56 -07:00
Elijah Newren
446cc5544a t2500: add various tests for nuking untracked files
Noting that unpack_trees treats reset=1 & update=1 as license to nuke
untracked files, I looked for code paths that use this combination and
tried to generate testcases which demonstrated unintentional loss of
untracked files and directories.  I found several.

I also include testcases for `git reset --{hard,merge,keep}`.  A hard
reset is perhaps the most direct test of unpack_tree's reset=1 behavior,
but we cannot make `git reset --hard` preserve untracked files without
some migration work.

Also, the two commands `checkout --force` (because of the --force) and
`read-tree --reset` (because it's plumbing and we need to keep it
backward compatible) were left out as we expect those to continue
removing untracked files and directories.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-24 09:24:25 -07:00
Junio C Hamano
50eb005eb3 Merge branch 'cb/plug-leaks-in-alloca-emu-users'
Leakfix.

* cb/plug-leaks-in-alloca-emu-users:
  t0000: avoid masking git exit value through pipes
  tree-diff: fix leak when not HAVE_ALLOCA_H
2021-09-23 13:44:49 -07:00
Junio C Hamano
bd42622e5f Merge branch 'ma/help-w-check-for-requested-page'
The error in "git help no-such-git-command" is handled better.

* ma/help-w-check-for-requested-page:
  help: make sure local html page exists before calling external processes
2021-09-23 13:44:48 -07:00
Junio C Hamano
c2e799012b Merge branch 'cb/unix-sockets-with-windows'
Adjust credential-cache helper to Windows.

* cb/unix-sockets-with-windows:
  git-compat-util: include declaration for unix sockets in windows
  credential-cache: check for windows specific errors
  t0301: fixes for windows compatibility
2021-09-23 13:44:48 -07:00
Junio C Hamano
0e35107e7d Merge branch 'ab/retire-option-argument'
An oddball OPTION_ARGUMENT feature has been removed from the
parse-options API.

* ab/retire-option-argument:
  parse-options API: remove OPTION_ARGUMENT feature
  difftool: use run_command() API in run_file_diff()
  difftool: prepare "diff" cmdline in cmd_difftool()
  difftool: prepare "struct child_process" in cmd_difftool()
2021-09-23 13:44:48 -07:00
Junio C Hamano
0a4cb1f1f2 Merge branch 'mr/bisect-in-c-4'
Rewrite of "git bisect" in C continues.

* mr/bisect-in-c-4:
  bisect--helper: retire `--bisect-next-check` subcommand
  bisect--helper: reimplement `bisect_run` shell function in C
  bisect--helper: reimplement `bisect_visualize()` shell function in C
  run-command: make `exists_in_PATH()` non-static
  t6030-bisect-porcelain: add test for bisect visualize
  t6030-bisect-porcelain: add tests to control bisect run exit cases
2021-09-23 13:44:48 -07:00
Junio C Hamano
57e4a7b633 Merge branch 'ab/unused-script-helpers'
Code clean-up.

* ab/unused-script-helpers:
  test-lib: remove unused $_x40 and $_z40 variables
  git-bisect: remove unused SHA-1 $x40 shell variable
  git-sh-setup: remove unused "pull with rebase" message
  git-submodule: remove unused is_zero_oid() function
2021-09-23 13:44:47 -07:00
Junio C Hamano
cabb41d0f6 Merge branch 'jk/http-server-protocol-versions'
Taking advantage of the CGI interface, http-backend has been
updated to enable protocol v2 automatically when the other side
asks for it.

* jk/http-server-protocol-versions:
  docs/protocol-v2: point readers transport config discussion
  docs/git: discuss server-side config for GIT_PROTOCOL
  docs/http-backend: mention v2 protocol
  http-backend: handle HTTP_GIT_PROTOCOL CGI variable
  t5551: test v2-to-v0 http protocol fallback
2021-09-23 13:44:47 -07:00
Junio C Hamano
ffb0387608 Merge branch 'ab/test-tool-run-command-cleanup'
Code clean-up.

* ab/test-tool-run-command-cleanup:
  test-tool run-command: fix flip-flop init pattern
2021-09-23 13:44:46 -07:00
Junio C Hamano
b83e131029 Merge branch 'en/tests-cleanup-leftover-untracked'
Test clean-up.

* en/tests-cleanup-leftover-untracked:
  tests: remove leftover untracked files
2021-09-23 13:44:46 -07:00
Junio C Hamano
6c84b007c4 Merge branch 'en/am-abort-fix'
When "git am --abort" fails to abort correctly, it still exited
with exit status of 0, which has been corrected.

* en/am-abort-fix:
  am: fix incorrect exit status on am fail to abort
  t4151: add a few am --abort tests
  git-am.txt: clarify --abort behavior
2021-09-23 13:44:45 -07:00
Junio C Hamano
06a0eeaa25 Merge branch 'ps/update-ref-batch-flush'
"git update-ref --stdin" failed to flush its output as needed,
which potentially led the conversation to a deadlock.

* ps/update-ref-batch-flush:
  t1400: avoid SIGPIPE race condition on fifo
  update-ref: fix streaming of status updates
2021-09-23 13:44:45 -07:00
Ævar Arnfjörð Bjarmason
956d2e4639 tests: add a test mode for SANITIZE=leak, run it in CI
While git can be compiled with SANITIZE=leak, we have not run
regression tests under that mode. Memory leaks have only been fixed as
one-offs without structured regression testing.

This change adds CI testing for it. We'll now build and small set of
whitelisted t00*.sh tests under Linux with a new job called
"linux-leaks".

The CI target uses a new GIT_TEST_PASSING_SANITIZE_LEAK=true test
mode. When running in that mode, we'll assert that we were compiled
with SANITIZE=leak. We'll then skip all tests, except those that we've
opted-in by setting "TEST_PASSES_SANITIZE_LEAK=true".

A test setting "TEST_PASSES_SANITIZE_LEAK=true" setting can in turn
make use of the "SANITIZE_LEAK" prerequisite, should they wish to
selectively skip tests even under
"GIT_TEST_PASSING_SANITIZE_LEAK=true". In the preceding commit we
started doing this in "t0004-unwritable.sh" under SANITIZE=leak, now
it'll combine nicely with "GIT_TEST_PASSING_SANITIZE_LEAK=true".

This is how tests that don't set "TEST_PASSES_SANITIZE_LEAK=true" will
be skipped under GIT_TEST_PASSING_SANITIZE_LEAK=true:

    $ GIT_TEST_PASSING_SANITIZE_LEAK=true ./t0001-init.sh
    1..0 # SKIP skip all tests in t0001 under SANITIZE=leak, TEST_PASSES_SANITIZE_LEAK not set

The intent is to add more TEST_PASSES_SANITIZE_LEAK=true annotations
as follow-up change, but let's start small to begin with.

In ci/run-build-and-tests.sh we make use of the default "*" case to
run "make test" without any GIT_TEST_* modes. SANITIZE=leak is known
to fail in combination with GIT_TEST_SPLIT_INDEX=true in
t0016-oidmap.sh, and we're likely to have other such failures in
various GIT_TEST_* modes. Let's focus on getting the base tests
passing, we can expand coverage to GIT_TEST_* modes later.

It would also be possible to implement a more lightweight version of
this by only relying on setting "LSAN_OPTIONS". See
<YS9OT/pn5rRK9cGB@coredump.intra.peff.net>[1] and
<YS9ZIDpANfsh7N+S@coredump.intra.peff.net>[2] for a discussion of
that. I've opted for this approach of adding a GIT_TEST_* mode instead
because it's consistent with how we handle other special test modes.

Being able to add a "!SANITIZE_LEAK" prerequisite and calling
"test_done" early if it isn't satisfied also means that we can more
incrementally add regression tests without being forced to fix
widespread and hard-to-fix leaks at the same time.

We have tests that do simple checking of some tool we're interested
in, but later on in the script might be stressing trace2, or common
sources of leaks like "git log" in combination with the tool (e.g. the
commit-graph tests). To be clear having a prerequisite could also be
accomplished by using "LSAN_OPTIONS" directly.

On the topic of "LSAN_OPTIONS": It would be nice to have a mode to
aggregate all failures in our various scripts, see [2] for a start at
doing that which sets "log_path" in "LSAN_OPTIONS". I've punted on
that for now, it can be added later.

As of writing this we've got major regressions between master..seen,
i.e. the t000*.sh tests and more fixed since 31f9acf9ce (Merge branch
'ah/plugleaks', 2021-08-04) have regressed recently.

See the discussion at <87czsv2idy.fsf@evledraar.gmail.com>[3] about
the lack of this sort of test mode, and 0e5bba53af (add UNLEAK
annotation for reducing leak false positives, 2017-09-08) for the
initial addition of SANITIZE=leak.

See also 09595ab381 (Merge branch 'jk/leak-checkers', 2017-09-19),
7782066f67 (Merge branch 'jk/apache-lsan', 2019-05-19) and the recent
936e58851a (Merge branch 'ah/plugleaks', 2021-05-07) for some of the
past history of "one-off" SANITIZE=leak (and more) fixes.

As noted in [5] we can't support this on OSX yet until Clang 14 is
released, at that point we'll probably want to resurrect that
"osx-leaks" job.

1. https://github.com/google/sanitizers/wiki/AddressSanitizerLeakSanitizer
2. https://lore.kernel.org/git/YS9OT%2Fpn5rRK9cGB@coredump.intra.peff.net/
3. https://lore.kernel.org/git/87czsv2idy.fsf@evledraar.gmail.com/
4. https://lore.kernel.org/git/YS9ZIDpANfsh7N+S@coredump.intra.peff.net/
5. https://lore.kernel.org/git/20210916035603.76369-1-carenas@gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-23 11:29:45 -07:00
Ævar Arnfjörð Bjarmason
2cdc292b31 Makefile: add SANITIZE=leak flag to GIT-BUILD-OPTIONS
When SANITIZE=leak is specified we'll now add a SANITIZE_LEAK flag to
GIT-BUILD-OPTIONS, this can then be picked up by the test-lib.sh,
which sets a SANITIZE_LEAK prerequisite.

We can then skip specific tests that are known to fail under
SANITIZE=leak, add one such annotation to t0004-unwritable.sh, which
now passes under SANITIZE=leak.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-23 11:29:45 -07:00
Junio C Hamano
77bd616367 Merge branch 'da/difftool-dir-diff-symlink-fix' into da/difftool
* da/difftool-dir-diff-symlink-fix:
  difftool: fix symlink-file writing in dir-diff mode
2021-09-23 11:26:17 -07:00
David Aguilar
5bafb3576a difftool: fix symlink-file writing in dir-diff mode
The difftool dir-diff mode handles symlinks by replacing them with their
readlink(2) values. This allows diff tools to see changes to symlinks
as if they were regular text diffs with the old and new path values.
This is analogous to what "git diff" displays when symlinks change.

The temporary diff directories that are created initially contain
symlinks because they get checked-out using a temporary index that
retains the original symlinks as checked-in to the repository.

A bug was introduced when difftool was rewritten in C that made
difftool write the readlink(2) contents into the pointed-to file rather
than the symlink itself. The write was going through the symlink and
writing to its target rather than writing to the symlink path itself.

Replace symlinks with raw text files by unlinking the symlink path
before writing the readlink(2) content into them.

When 18ec800512 (difftool: handle modified symlinks in dir-diff mode,
2017-03-15) added handling for modified symlinks this bug got recorded
in the test suite. The tests included the pointed-to symlink target
paths. These paths were being reported because difftool was erroneously
writing to them, but they should have never been reported nor written.

Correct the modified-symlinks test cases by removing the target files
from the expected output.

Add a test to ensure that symlinks are written with the readlink(2)
values and that the target files contain their original content.

Reported-by: Alan Blotz <work@blotz.org>
Helped-by: Đoàn Trần Công Danh <congdanhqx@gmail.com>
Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-23 11:24:41 -07:00
Ævar Arnfjörð Bjarmason
a9bacccae5 help / completion: make "git help" do the hard work
The "help" builtin has been able to emit configuration variables since
e17ca92637 (completion: drop the hard coded list of config vars,
2018-05-26), but it hasn't produced exactly the format the completion
script wanted. Let's do that.

We got partway there in 2675ea1cc0 (completion: use 'sort -u' to
deduplicate config variable names, 2019-08-13) and
d9438873c4 (completion: deduplicate configuration sections,
2019-08-13), but after both we still needed some sorting,
de-duplicating and awk post-processing of the list.

We can instead simply do the relevant parsing ourselves (we were doing
most of it already), and call string_list_remove_duplicates() after
already sorting the list, so the caller doesn't need to invoke "sort
-u". The "--config-for-completion" output is the same as before after
being passed through "sort -u".

Then add a new "--config-sections-for-completion" option. Under that
output we'll emit config sections like "alias" (instead of "alias." in
the --config-for-completion output).

We need to be careful to leave the "--config-for-completion" option
compatible with users git, but are still running a shell with an older
git-completion.bash. If we e.g. changed the option name they'd see
messages about git-completion.bash being unable to find the
"--config-for-completion" option.

Such backwards compatibility isn't something we should bend over
backwards for, it's only helping users who:

 * Upgrade git
 * Are in an old shell
 * The git-completion.bash in that shell hasn't cached the old
   "--config-for-completion" output already.

But since it's easy in this case to retain compatibility, let's do it,
the older versions of git-completion.bash won't care that the input
they get doesn't change after a "sort -u".

While we're at it let's make "--config-for-completion" die if there's
anything left over in "argc", and do the same in the new
"--config-sections-for-completion" option.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-23 10:30:43 -07:00
Ævar Arnfjörð Bjarmason
5a5f04d86b help tests: test --config-for-completion option & output
Add a regression test for the --config-for-completion option, this was
tested for indirectly with the test added in 7a09a8f093 (completion:
add tests for 'git config' completion, 2019-08-13), but let's do it
directly here as well.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-23 10:30:43 -07:00
Ævar Arnfjörð Bjarmason
0a5940fbe7 help: correct logic error in combining --all and --guides
The --all and --guides commands could be combined, which wouldn't have
any impact on the output except for:

    git help --all --guides --no-verbose

Listing the guide alongside that output was clearly not intended, so
let's error out here. See 002b726a40 (builtin/help.c: add
list_common_guides_help() function, 2013-04-02) for the initial
implementation.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-23 10:30:43 -07:00
Ævar Arnfjörð Bjarmason
1ed4bef6b4 help: correct logic error in combining --all and --config
Fix a bug in the --config option that's been there ever since its
introduction in 3ac68a93fd (help: add --config to list all available
config, 2018-05-26). Die when --all and --config are combined,
combining them doesn't make sense.

The code for the --config option when combined with an earlier
refactoring done to support the --guide option in
65f98358c0 (builtin/help.c: add --guide option, 2013-04-02) would
cause us to take the "--all" branch early and ignore the --config
option.

Let's instead list these as incompatible, both in the synopsis and
help output, and enforce it in the code itself.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-23 10:30:43 -07:00
Ævar Arnfjörð Bjarmason
ff76fc841f help tests: add test for --config output
Add a missing test for checking what the --config output added in
ac68a93fd2 (help: add --config to list all available config,
2018-05-26) looks like. We should not be emitting anything except
config variables and the brief usage information at the end here.

The second test regexp here might not match three-level variables in
general, as their second level could contain ".", but in this case
we're always emitting what we extract from the documentation, so it's
all strings like:

    foo.<name>.bar

If we did introduce something like variable example content here we'd
like this to break, since we'd then be likely to break the
git-completion.bash.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-23 10:30:43 -07:00
Ævar Arnfjörð Bjarmason
9856ea6785 help: correct usage & behavior of "git help --guides"
As noted in 65f98358c0 (builtin/help.c: add --guide option,
2013-04-02) and a133737b80 (doc: include --guide option description
for "git help", 2013-04-02) which introduced the --guide option, it
cannot be combined with e.g. <command>.

Change the command and the "SYNOPSIS" section to reflect that desired
behavior. Now that we assert this in code we don't need to
exhaustively describe the previous confusing behavior in the
documentation either, instead of silently ignoring the provided
argument we'll now error out.

The "We're done. Ignore any remaining args" comment added in
15f7d49438 (builtin/help.c: split "-a" processing into two,
2013-04-02) can now be removed, it's obvious that we're asserting the
behavior with the check of "argc".

The "--config" option is still missing from the synopsis, it will be
added in a subsequent commit where we'll fix bugs in its
implementation.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-23 10:30:43 -07:00
Jeff King
b66c77a64e http: match headers case-insensitively when redacting
When HTTP/2 is in use, we fail to correctly redact "Authorization" (and
other) headers in our GIT_TRACE_CURL output.

We get the headers in our CURLOPT_DEBUGFUNCTION callback, curl_trace().
It passes them along to curl_dump_header(), which in turn checks
redact_sensitive_header(). We see the headers as a text buffer like:

  Host: ...
  Authorization: Basic ...

After breaking it into lines, we match each header using skip_prefix().
This is case-sensitive, even though HTTP headers are case-insensitive.
This has worked reliably in the past because these headers are generated
by curl itself, which is predictable in what it sends.

But when HTTP/2 is in use, instead we get a lower-case "authorization:"
header, and we fail to match it. The fix is simple: we should match with
skip_iprefix().

Testing is more complicated, though. We do have a test for the redacting
feature, but we don't hit the problem case because our test Apache setup
does not understand HTTP/2. You can reproduce the issue by applying this
on top of the test change in this patch:

	diff --git a/t/lib-httpd/apache.conf b/t/lib-httpd/apache.conf
	index afa91e38b0..19267c7107 100644
	--- a/t/lib-httpd/apache.conf
	+++ b/t/lib-httpd/apache.conf
	@@ -29,6 +29,9 @@ ErrorLog error.log
	 	LoadModule setenvif_module modules/mod_setenvif.so
	 </IfModule>

	+LoadModule http2_module modules/mod_http2.so
	+Protocols h2c
	+
	 <IfVersion < 2.4>
	 LockFile accept.lock
	 </IfVersion>
	@@ -64,8 +67,8 @@ LockFile accept.lock
	 <IfModule !mod_access_compat.c>
	 	LoadModule access_compat_module modules/mod_access_compat.so
	 </IfModule>
	-<IfModule !mod_mpm_prefork.c>
	-	LoadModule mpm_prefork_module modules/mod_mpm_prefork.so
	+<IfModule !mod_mpm_event.c>
	+	LoadModule mpm_event_module modules/mod_mpm_event.so
	 </IfModule>
	 <IfModule !mod_unixd.c>
	 	LoadModule unixd_module modules/mod_unixd.so
	diff --git a/t/t5551-http-fetch-smart.sh b/t/t5551-http-fetch-smart.sh
	index 1c2a444ae7..ff74f0ae8a 100755
	--- a/t/t5551-http-fetch-smart.sh
	+++ b/t/t5551-http-fetch-smart.sh
	@@ -24,6 +24,10 @@ test_expect_success 'create http-accessible bare repository' '
	 	git push public main:main
	 '

	+test_expect_success 'prefer http/2' '
	+	git config --global http.version HTTP/2
	+'
	+
	 setup_askpass_helper

	 test_expect_success 'clone http repository' '

but this has a few issues:

  - it's not necessarily portable. The http2 apache module might not be
    available on all systems. Further, the http2 module isn't compatible
    with the prefork mpm, so we have to switch to something else. But we
    don't necessarily know what's available. It would be nice if we
    could have conditional config, but IfModule only tells us if a
    module is already loaded, not whether it is available at all.

    This might be a non-issue. The http tests are already optional, and
    modern-enough systems may just have both of these. But...

  - if we do this, then we'd no longer be testing HTTP/1.1 at all. I'm
    not sure how much that matters since it's all handled by curl under
    the hood, but I'd worry that some detail leaks through. We'd
    probably want two scripts running similar tests, one with HTTP/2 and
    one with HTTP/1.1.

  - speaking of which, a later test fails with the patch above! The
    problem is that it is making sure we used a chunked
    transfer-encoding by looking for that header in the trace. But
    HTTP/2 doesn't support that, as it has its own streaming mechanisms
    (the overall operation works fine; we just don't see the header in
    the trace).

Furthermore, even with the changes above, this test still does not
detect the current failure, because we see _both_ HTTP/1.1 and HTTP/2
requests, which confuse it. Quoting only the interesting bits from the
resulting trace file, we first see:

  => Send header: GET /auth/smart/repo.git/info/refs?service=git-upload-pack HTTP/1.1
  => Send header: Connection: Upgrade, HTTP2-Settings
  => Send header: Upgrade: h2c
  => Send header: HTTP2-Settings: AAMAAABkAAQCAAAAAAIAAAAA

  <= Recv header: HTTP/1.1 401 Unauthorized
  <= Recv header: Date: Wed, 22 Sep 2021 20:03:32 GMT
  <= Recv header: Server: Apache/2.4.49 (Debian)
  <= Recv header: WWW-Authenticate: Basic realm="git-auth"

So the client asks for HTTP/2, but Apache does not do the upgrade for
the 401 response. Then the client repeats with credentials:

  => Send header: GET /auth/smart/repo.git/info/refs?service=git-upload-pack HTTP/1.1
  => Send header: Authorization: Basic <redacted>
  => Send header: Connection: Upgrade, HTTP2-Settings
  => Send header: Upgrade: h2c
  => Send header: HTTP2-Settings: AAMAAABkAAQCAAAAAAIAAAAA

  <= Recv header: HTTP/1.1 101 Switching Protocols
  <= Recv header: Upgrade: h2c
  <= Recv header: Connection: Upgrade
  <= Recv header: HTTP/2 200
  <= Recv header: content-type: application/x-git-upload-pack-advertisement

So the client does properly redact there, because we're speaking
HTTP/1.1, and the server indicates it can do the upgrade. And then the
client will make further requests using HTTP/2:

  => Send header: POST /auth/smart/repo.git/git-upload-pack HTTP/2
  => Send header: authorization: Basic dXNlckBob3N0OnBhc3NAaG9zdA==
  => Send header: content-type: application/x-git-upload-pack-request

And there we can see that the credential is _not_ redacted. This part of
the test is what gets confused:

	# Ensure that there is no "Basic" followed by a base64 string, but that
	# the auth details are redacted
	! grep "Authorization: Basic [0-9a-zA-Z+/]" trace &&
	grep "Authorization: Basic <redacted>" trace

The first grep does not match the un-redacted HTTP/2 header, because
it insists on an uppercase "A". And the second one does find the
HTTP/1.1 header. So as far as the test is concerned, everything is OK,
but it failed to notice the un-redacted lines.

We can make this test (and the other related ones) more robust by adding
"-i" to grep case-insensitively. This isn't really doing anything for
now, since we're not actually speaking HTTP/2, but it future-proofs the
tests for a day when we do (either we add explicit HTTP/2 test support,
or it's eventually enabled by default by our Apache+curl test setup).
And it doesn't hurt in the meantime for the tests to be more careful.

The change to use "grep -i", coupled with the changes to use HTTP/2
shown above, causes the test to fail with the current code, and pass
after this patch is applied.

And finally, there's one other way to demonstrate the issue (and how I
actually found it originally). Looking at GIT_TRACE_CURL output against
github.com, you'll see the unredacted output, even if you didn't set
http.version. That's because setting it is only necessary for curl to
send the extra headers in its HTTP/1.1 request that say "Hey, I speak
HTTP/2; upgrade if you do, too". But for a production site speaking
https, the server advertises via ALPN, a TLS extension, that it supports
HTTP/2, and the client can immediately start using it.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-22 21:24:58 -07:00
Ævar Arnfjörð Bjarmason
2e54907e83 test-lib tests: get rid of copy/pasted mock test code
Now that we've split up the write_sub_test_lib_test*() and
run_sub_test_lib_test*() functions let's fix those tests in
t0000-basic.sh that were verbosely copy/pasting earlier tests.

That we caught all of them was asserted with a follow-up change that's
not part of this series[1], we might add such a duplication check at
some later time, but for now let's just one-off remove the duplicate
boilerplate.

1. https://lore.kernel.org/git/patch-v3-6.9-bc79b29f3c-20210805T103237Z-avarab@gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-22 16:22:41 -07:00
Ævar Arnfjörð Bjarmason
56722a0635 test-lib tests: assert 1 exit code, not non-zero
Improve the testing for test-lib.sh itself to assert that we have a
exit code of 1, not any non-zero. Improves code added in
0445e6f0a1 (test-lib: '--run' to run only specific tests,
2014-04-30).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-22 16:22:41 -07:00
Ævar Arnfjörð Bjarmason
e07b817cfc test-lib tests: refactor common part of check_sub_test_lib_test*()
Refactor the two check_sub_test_lib_test*() functions to avoid
duplicating the same comparison they did of stdout. This duplication
was initially added when check_sub_test_lib_test_err() was added in
0445e6f0a1 (test-lib: '--run' to run only specific tests,
2014-04-30).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-22 16:22:41 -07:00
Ævar Arnfjörð Bjarmason
12fe4909fa test-lib tests: avoid subshell for "test_cmp" for readability
The use of a sub-shell for running the test_cmp of stdout/stderr for
the test author was introduced in this form in 565b6fa87b (tests:
refactor mechanics of testing in a sub test-lib, 2012-12-16), but from
looking at the history that seemed to have diligently copied my
original ad-hoc implementation in 7b90511970 (t/t0000-basic.sh: Run
the passing TODO test inside its own test-lib, 2010-08-19).

There's no reason to use a subshell here, we try to avoid it in
general. It also improves readability, if the test fails we print out
the relative path in the trash directory that needs to be looked
at.

Before that was mostly obscured, since the "write_sub_test_lib_test"
will pick the directory for you from the test name.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-22 16:22:41 -07:00
Ævar Arnfjörð Bjarmason
c3ff7be6fb test-lib tests: don't provide a description for the sub-tests
Change the $test_description provided for the generated subtests to be
constant, since the only purpose of having it is that test-lib.sh will
barf if it isn't supplied.

The other purpose of having it was to effectively split up the test
description between the argument to test_expect_success and the
argument to "write_and_run_sub_test_lib_test". Let's only use one of
the two.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-22 16:22:41 -07:00
Ævar Arnfjörð Bjarmason
9f0a45208d test-lib tests: split up "write and run" into two functions
Refactor the function to write and run tests of the test-lib.sh output
into two functions.

When this was added back in 565b6fa87b (tests: refactor mechanics of
testing in a sub test-lib, 2012-12-16) there was no reason to do this,
but since we started supporting test arguments in
517cd55fd5 (test-lib: self-test that --verbose works, 2013-06-23)
we've started to write out duplicate tests simply to test different
arguments, now we'll be able to re-use them.

This change doesn't consolidate any of those tests yet, it just makes
it possible to do so. All the changes in t0000-basic.sh are a simple
search-replacement.

Since the _run_sub_test_lib_test_common() function doesn't handle
running the test anymore we can do away with the sub-shell, which was
used to scope an "unset" and "export" shell variables.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-22 16:22:41 -07:00
Derrick Stolee
f9d65b04cd t/perf/run: fix bin-wrappers computation
The GIT_TEST_INSTALLED was moved from perf-lib.sh to run in df0f5021
(perf-lib.sh: remove GIT_TEST_INSTALLED from perf-lib.sh, 2019-05-07)
and that included a change to how it inspected the existence of a
bin-wrappers directory. However, that included a typo that made the
match of bin-wrappers never work. Specifically, the assignment was

	mydir_abs_wrappers="$mydir_abs_wrappers/bin-wrappers"

which uses the same variable before it is initialized. By changing it to

	mydir_abs_wrappers="$mydir_abs/bin-wrappers"

We can correctly use the bin-wrappers directory.

This is critical to successfully computing performance of commands that
execute subcommands. The bin-wrappers ensure that the --exec-path is set
correctly.

Reported-by: Victoria Dye <vdye@github.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-22 13:26:11 -07:00
Ævar Arnfjörð Bjarmason
c6b4888b3f environment.c: remove test-specific "ignore_untracked..." variable
Instead of the global ignore_untracked_cache_config variable added in
dae6c322fa (test-dump-untracked-cache: don't modify the untracked
cache, 2016-01-27) we can make use of the new facility to set config
via environment variables added in d8d77153ea (config: allow
specifying config entries via envvar pairs, 2021-01-12).

It's arguably a bit hacky to use setenv() and getenv() to pass
messages between the same program, but since the test helpers are not
the main intended audience of repo-settings.c I think it's better than
hardcoding the test-only special-case in prepare_repo_settings().

This uses the xsetenv() wrapper added in the preceding commit, if we
don't set these in the environment we'll fail in
t7063-status-untracked-cache.sh, but let's fail earlier anyway if that
were to happen.

This breaks any parent process that's potentially using the
GIT_CONFIG_* and GIT_CONFIG_PARAMETERS mechanism to pass one-shot
config setting down to a git subprocess, but in this case we don't
care about the general case of such potential parents. This process
neither spawns other "git" processes, nor is it interested in other
configuration. We might want to pick up other test modes here, but
those will be passed via GIT_TEST_* environment variables.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-22 13:15:00 -07:00
Phillip Wood
7740ac691d rebase: dereference tags
A rebase started with 'git rebase <A> <B>' is conceptually to first
checkout <B> and run 'git rebase <A>' starting from that state.  'git
rebase --abort' in the middle of such a rebase should take us back to
the state we checked out <B>.

This used to work, even when <B> is a tag that points at a commit,
until Git 2.20.0 when the command was reimplemented in C.  The command
now complains that the tag object itself cannot be checked out, which
may be technically correct but is not what the user asked to do.

Fix this old regression by using lookup_commit_reference_by_name()
when parsing <B>. The scripted version did not need to peel the tag
because the commands it passed the tag to (e.g 'git reset') peeled the
tag themselves.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-22 12:04:52 -07:00
Taylor Blau
0394f8d002 builtin/multi-pack-index.c: disable top-level --[no-]progress
In a similar spirit as the previous patch, let sub-commands which
support showing or hiding a progress meter handle parsing the
`--progress` or `--no-progress` option, but do not expose it as an
option to the top-level `multi-pack-index` builtin.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-22 09:26:29 -07:00
Junio C Hamano
71e36361bf Merge branch 'jk/t5562-racefix'
Test update.

* jk/t5562-racefix:
  t5562: use alarm() to interrupt timed child-wait
2021-09-20 15:20:46 -07:00
Junio C Hamano
a16dd13740 Merge branch 'ds/mergies-with-sparse-index'
Various mergy operations have been prepared to work efficiently
with the sparse index.

* ds/mergies-with-sparse-index:
  sparse-index: integrate with cherry-pick and rebase
  sequencer: ensure full index if not ORT strategy
  t1092: add cherry-pick, rebase tests
  merge-ort: expand only for out-of-cone conflicts
  merge: make sparse-aware with ORT
  diff: ignore sparse paths in diffstat
2021-09-20 15:20:45 -07:00
Junio C Hamano
dc89c34d9e Merge branch 'ds/sparse-index-ignored-files'
In cone mode, the sparse-index code path learned to remove ignored
files (like build artifacts) outside the sparse cone, allowing the
entire directory outside the sparse cone to be removed, which is
especially useful when the sparse patterns change.

* ds/sparse-index-ignored-files:
  sparse-checkout: clear tracked sparse dirs
  sparse-index: add SPARSE_INDEX_MEMORY_ONLY flag
  attr: be careful about sparse directories
  sparse-checkout: create helper methods
  sparse-index: use WRITE_TREE_MISSING_OK
  sparse-index: silently return when cache tree fails
  unpack-trees: fix nested sparse-dir search
  sparse-index: silently return when not using cone-mode patterns
  t7519: rewrite sparse index test
2021-09-20 15:20:44 -07:00
Junio C Hamano
5331af2352 Merge branch 'ab/serve-cleanup'
Code clean-up around "git serve".

* ab/serve-cleanup:
  upload-pack: document and rename --advertise-refs
  serve.[ch]: remove "serve_options", split up --advertise-refs code
  {upload,receive}-pack tests: add --advertise-refs tests
  serve.c: move version line to advertise_capabilities()
  serve: move transfer.advertiseSID check into session_id_advertise()
  serve.[ch]: don't pass "struct strvec *keys" to commands
  serve: use designated initializers
  transport: use designated initializers
  transport: rename "fetch" in transport_vtable to "fetch_refs"
  serve: mark has_capability() as static
2021-09-20 15:20:43 -07:00
Junio C Hamano
75405e7270 Merge branch 'dt/submodule-diff-fixes'
"git diff --submodule=diff" showed failure from run_command() when
trying to run diff inside a submodule, when the user manually
removes the submodule directory.

* dt/submodule-diff-fixes:
  diff --submodule=diff: don't print failure message twice
  diff --submodule=diff: do not fail on ever-initialied deleted submodules
  t4060: remove unused variable
2021-09-20 15:20:41 -07:00
Junio C Hamano
ed8794ef7a Merge branch 'lh/systemd-timers'
"git maintenance" scheduler learned to use systemd timers as a
possible backend.

* lh/systemd-timers:
  maintenance: add support for systemd timers on Linux
  maintenance: `git maintenance run` learned `--scheduler=<scheduler>`
  cache.h: Introduce a generic "xdg_config_home_for(…)" function
2021-09-20 15:20:40 -07:00
Junio C Hamano
11e5d0a262 Merge branch 'jt/grep-wo-submodule-odb-as-alternate'
The code to make "git grep" recurse into submodules has been
updated to migrate away from the "add submodule's object store as
an alternate object store" mechanism (which is suboptimal).

* jt/grep-wo-submodule-odb-as-alternate:
  t7814: show lack of alternate ODB-adding
  submodule-config: pass repo upon blob config read
  grep: add repository to OID grep sources
  grep: allocate subrepos on heap
  grep: read submodule entry with explicit repo
  grep: typesafe versions of grep_source_init
  grep: use submodule-ODB-as-alternate lazy-addition
  submodule: lazily add submodule ODBs as alternates
2021-09-20 15:20:39 -07:00
Junio C Hamano
0649303820 Merge branch 'tb/multi-pack-bitmaps'
The reachability bitmap file used to be generated only for a single
pack, but now we've learned to generate bitmaps for history that
span across multiple packfiles.

* tb/multi-pack-bitmaps: (29 commits)
  pack-bitmap: drop bitmap_index argument from try_partial_reuse()
  pack-bitmap: drop repository argument from prepare_midx_bitmap_git()
  p5326: perf tests for MIDX bitmaps
  p5310: extract full and partial bitmap tests
  midx: respect 'GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP'
  t7700: update to work with MIDX bitmap test knob
  t5319: don't write MIDX bitmaps in t5319
  t5310: disable GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP
  t0410: disable GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP
  t5326: test multi-pack bitmap behavior
  t/helper/test-read-midx.c: add --checksum mode
  t5310: move some tests to lib-bitmap.sh
  pack-bitmap: write multi-pack bitmaps
  pack-bitmap: read multi-pack bitmaps
  pack-bitmap.c: avoid redundant calls to try_partial_reuse
  pack-bitmap.c: introduce 'bitmap_is_preferred_refname()'
  pack-bitmap.c: introduce 'nth_bitmap_object_oid()'
  pack-bitmap.c: introduce 'bitmap_num_objects()'
  midx: avoid opening multiple MIDXs when writing
  midx: close linked MIDXs, avoid leaking memory
  ...
2021-09-20 15:20:39 -07:00
Jeff King
6b58df54cf clone: handle unborn branch in bare repos
When cloning a repository with an unborn HEAD, we'll set the local HEAD
to match it only if the local repository is non-bare. This is
inconsistent with all other combinations:

  remote HEAD       | local repo | local HEAD
  -----------------------------------------------
  points to commit  | non-bare   | same as remote
  points to commit  | bare       | same as remote
  unborn            | non-bare   | same as remote
  unborn            | bare       | local default

So I don't think this is some clever or subtle behavior, but just a bug
in 4f37d45706 (clone: respect remote unborn HEAD, 2021-02-05). And it's
easy to see how we ended up there. Before that commit, the code to set
up the HEAD for an empty repo was guarded by "if (!option_bare)". That's
because the only thing it did was call install_branch_config(), and we
don't want to do so for a bare repository (unborn HEAD or not).

That commit put the handling of unborn HEADs into the same block, since
those also need to call install_branch_config(). But the unborn case has
an additional side effect of calling create_symref(), and we want that
to happen whether we are bare or not.

This patch just pulls all of the "figure out the default branch" code
out of the "!option_bare" block. Only the actual config installation is
kept there.

Note that this does mean we might allocate "ref" and not use it (if the
remote is empty but did not advertise an unborn HEAD). But that's not
really a big deal since this isn't a hot code path, and it keeps the
code simple. The alternative would be handling unborn_head_target
separately, but that gets confusing since its memory ownership is
tangled up with the "ref" variable.

There's just one new test, for the case we're fixing. The other ones in
the table are handled elsewhere (the unborn non-bare case just above,
and the actually-born cases in t5601, t5606, and t5609, as they do not
require v2's "unborn" protocol extension).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-20 14:05:36 -07:00
Junio C Hamano
93a8ed28ea Merge branch 'ab/retire-option-argument' into da/difftool
* ab/retire-option-argument:
  parse-options API: remove OPTION_ARGUMENT feature
  difftool: use run_command() API in run_file_diff()
  difftool: prepare "diff" cmdline in cmd_difftool()
  difftool: prepare "struct child_process" in cmd_difftool()
2021-09-20 11:42:34 -07:00
Junio C Hamano
04d3761db2 Merge branch 'en/am-abort-fix' into en/removing-untracked-fixes
* en/am-abort-fix:
  am: fix incorrect exit status on am fail to abort
  t4151: add a few am --abort tests
  git-am.txt: clarify --abort behavior
2021-09-20 11:22:09 -07:00
Jeff Hostetler
05881a6fc9 t/helper/simple-ipc: convert test-simple-ipc to use start_bg_command
Convert test helper to use `start_bg_command()` when spawning a server
daemon in the background rather than blocks of platform-specific code.

Also, while here, remove _() translation around error messages since
this is a test helper and not Git code.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-20 08:57:58 -07:00
Jeff Hostetler
a3e2033e04 simple-ipc: preparations for supporting binary messages.
Add `command_len` argument to the Simple IPC API.

In my original Simple IPC API, I assumed that the request would always
be a null-terminated string of text characters.  The `command`
argument was just a `const char *`.

I found a caller that would like to pass a binary command to the
daemon, so I am amending the Simple IPC API to receive `const char
*command, size_t command_len` arguments.

I considered changing the `command` argument to be a `void *`, but the
IPC layer simply passes it to the pkt-line layer which takes a `const
char *`, so to avoid confusion I left it as is.

Note, the response side has always been a `struct strbuf` which
includes the buffer and length, so we already support returning a
binary answer.  (Yes, it feels a little weird returning a binary
buffer in a `strbuf`, but it works.)

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-20 08:57:58 -07:00
Taylor Blau
54156af0d6 t5326: test propagating hashcache values
Now that we both can propagate values from the hashcache, and respect
the configuration to enable the hashcache at all, test that both of
these function correctly by hardening their behavior with a test.

Like the hash-cache in classic single-pack bitmaps, this helps more
proportionally the more up-to-date your bitmap coverage is. When our
bitmap coverage is out-of-date with the ref tips, we spend more time
proportionally traversing, and all of that traversal gets the name-hash
filled in.

But for the up-to-date bitmaps, this helps quite a bit. These numbers
are on git.git, with `pack.threads=1` to help see the difference
reflected in the overall runtime.

    Test                            origin/tb/multi-pack-bitmaps   HEAD
    -------------------------------------------------------------------------------------
    5326.4: simulated clone         1.87(1.80+0.07)                1.46(1.42+0.03) -21.9%
    5326.5: simulated fetch         2.66(2.61+0.04)                1.47(1.43+0.04) -44.7%
    5326.6: pack to file (bitmap)   2.74(2.62+0.12)                1.89(1.82+0.07) -31.0%

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-17 14:34:48 -07:00
Taylor Blau
bf4a60874a p5326: generate pack bitmaps before writing the MIDX bitmap
To help test the performance of permuting the contents of the hash-cache
when generating a MIDX bitmap, we need a bitmap which has its hash-cache
populated.

And since multi-pack bitmaps don't add *new* values to the hash-cache,
we have to rely on a single-pack bitmap to generate those values for us.

Therefore, generate a pack bitmap before the MIDX one in order to ensure
that the MIDX bitmap has entries in its hash-cache. Since we don't want
to time generating the pack bitmap, move that to a non-perf test run
before we try to generate the MIDX bitmap.

Likewise, get rid of the pack bitmap afterwords, to make certain that we
are not accidentally using it in the performance tests run later on.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-17 14:34:48 -07:00
Carlo Marcelo Arenas Belón
bffcb4d9d6 git-cvsserver: protect against NULL in crypt(3)
Some versions of crypt(3) will return NULL when passed an unsupported
hash type (ex: OpenBSD with DES), so check for undef instead of using
it directly.

Also use this to probe the system and select a better hash function in
the tests, so it can pass successfully.

Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
[jc: <CAPUEspjqD5zy8TLuFA96usU7FYi=0wF84y7NgOVFqegtxL9zbw@mail.gmail.com>]
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-16 20:47:23 -07:00
Carlo Marcelo Arenas Belón
a7775c7eb8 git-cvsserver: use crypt correctly to compare password hashes
c057bad370 (git-cvsserver: use a password file cvsserver pserver,
2010-05-15) adds a way for `git cvsserver` to provide authenticated
pserver accounts without having clear text passwords, but uses the
username instead of the password to the call for crypt(3).

Correct that, and make sure the documentation correctly indicates how
to obtain hashed passwords that could be used to populate this
configuration, as well as correcting the hash that was used for the
tests.

This change will require that any user of this feature updates the
hashes in their configuration, but has the advantage of using a more
similar format than cvs uses, probably also easying any migration.

Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-16 15:06:24 -07:00
Carlo Marcelo Arenas Belón
66c0c44df6 t0000: avoid masking git exit value through pipes
9af0b8dbe2 (t0000-basic: more commit-tree tests., 2006-04-26) adds
tests for commit-tree that mask the return exit from git as described
in a378fee5b0 (Documentation: add shell guidelines, 2018-10-05).

Fix the tests, to avoid pipes by using a temporary file instead.

Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-16 13:43:42 -07:00
Junio C Hamano
2b2af95908 Merge branch 'pb/test-use-user-env'
Teach "test_pause" and "debug" helpers to allow using the HOME and
TERM environment variables the user usually uses.

* pb/test-use-user-env:
  test-lib-functions: keep user's debugger config files and TERM in 'debug'
  test-lib-functions: optionally keep HOME, TERM and SHELL in 'test_pause'
  test-lib-functions: use 'TEST_SHELL_PATH' in 'test_pause'
2021-09-15 13:15:26 -07:00
Junio C Hamano
c76fcf3e46 Merge branch 'jc/trivial-threeway-binary-merge'
The "git apply -3" code path learned not to bother the lower level
merge machinery when the three-way merge can be trivially resolved
without the content level merge.

* jc/trivial-threeway-binary-merge:
  apply: resolve trivial merge without hitting ll-merge with "--3way"
2021-09-15 13:15:26 -07:00
Junio C Hamano
10de757a09 Merge branch 'ab/send-email-config-fix'
Regression fix.

* ab/send-email-config-fix:
  send-email: fix a "first config key wins" regression in v2.33.0
2021-09-15 13:15:24 -07:00
Jeff King
7c1200745b t1400: avoid SIGPIPE race condition on fifo
t1400.190 sometimes fails or even hangs because of the way it uses
fifos. Our goal is to interactively read and write lines from
update-ref, so we have two fifos, in and out. We open a descriptor
connected to "in" and redirect output to that, so that update-ref does
not see EOF as it would if we opened and closed it for each "echo" call.

But we don't do the same for the output. This leads to a race where our
"read response <out" has not yet opened the fifo, but update-ref tries
to write to it and gets SIGPIPE. This can result in the test failing, or
worse, hanging as we wait forever for somebody to write to the pipe.

This is the same proble we fixed in 4783e7ea83 (t0008: avoid SIGPIPE
race condition on fifo, 2013-07-12), and we can fix it the same way, by
opening a second long-running descriptor.

Before this patch, running:

  ./t1400-update-ref.sh --run=1,190 --stress

failed or hung within a few dozen iterations. After it, I ran it for
several hundred without problems.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-15 13:06:50 -07:00
Jeff King
ccf094788c ls-refs: reject unknown arguments
The v2 ls-refs command may receive extra arguments from the client, one
per pkt-line. The spec is pretty clear that the arguments must come from
a specified set, but we silently ignore any unknown entries. For a
well-behaved client this doesn't matter, but it makes testing and
debugging more confusing. Let's tighten this up to match the spec.

In theory this liberal behavior _could_ be useful for extending the
protocol. But:

  - every other part of the protocol requires that the server first
    indicate that it supports the argument; this includes the fetch and
    object-info commands, plus the "unborn" capability added to ls-refs
    itself

  - it's not a very good extension mechanism anyway; without the server
    advertising support, clients would have no idea if the argument was
    silently ignored, or accepted and simply had no effect

So we're not really losing anything by tightening this.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-15 12:25:19 -07:00
Jeff King
0ab7eeccd9 serve: reject commands used as capabilities
Our table of v2 "capabilities" contains everything we might tell the
client we support. But there are differences in how we expect the client
to respond. Some of the entries are true capabilities (i.e., we expect
the client to say "yes, I support this"), and some are ones we expect
them to send as commands (with "command=ls-refs" or similar).

When we receive a capability used as a command, we complain about that.
But when we receive a command used as a capability (e.g., just "ls-refs"
in a pkt-line by itself), we silently ignore it.

This isn't really hurting anything (clients shouldn't send it, and we'll
ignore it), but we can tighten up the protocol to match what we expect
to happen.

There are two new tests here. The first one checks a capability used as
a command, which already passes. The second tests a command as a
capability, which this patch fixes.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-15 12:25:19 -07:00
Jeff King
108c265f27 serve: reject bogus v2 "command=ls-refs=foo"
When we see a line from the client like "command=ls-refs", we parse
everything after the equals sign as a capability, which we check against
our capabilities table. If we don't recognize the command (e.g.,
"command=foo"), we'll reject it.

But in parse_command(), we use the same get_capability() parser for
parsing non-command lines. So if we see "command=ls-refs=foo", we will
feed "ls-refs=foo" to get_capability(), which will say "OK, that's
ls-refs, with value 'foo'". But then we simply ignore the value
entirely.

The client is violating the spec here, which says:

      command = PKT-LINE("command=" key LF)
      key = 1*(ALPHA | DIGIT | "-_")

I.e., the key is not even allowed to have an equals sign in it. Whereas
a real non-command capability does allow a value:

      capability = PKT-LINE(key[=value] LF)

So by reusing the same get_capability() parser, we are mixing up the
"key" and "capability" tokens. However, since that parser tells us
whether it saw an "=", we can still use it; we just need to reject any
input that produces a non-NULL value field.

The current behavior isn't really hurting anything (the client should
never send such a request, and if it does, we just ignore the "value"
part). But since it does violate the spec, let's tighten it up to
prevent any surprising behavior.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-15 12:25:19 -07:00
Jeff King
7f0e4f6ac2 ls-refs: ignore very long ref-prefix counts
Because each "ref-prefix" capability from the client comes in its own
pkt-line, there's no limit to the number of them that a misbehaving
client may send. We read them all into a strvec, which means the client
can waste arbitrary amounts of our memory by just sending us "ref-prefix
foo" over and over.

One possible solution is to just drop the connection when the limit is
reached. If we set it high enough, then only misbehaving or malicious
clients would hit it. But "high enough" is vague, and it's unfriendly if
we guess wrong and a legitimate client hits this.

But we can do better. Since supporting the ref-prefix capability is
optional anyway, the client has to further cull the response based on
their own patterns. So we can simply ignore the patterns once we cross a
certain threshold. Note that we have to ignore _all_ patterns, not just
the ones past our limit (since otherwise we'd send too little data).

The limit here is fairly arbitrary, and probably much higher than anyone
would need in practice. It might be worth limiting it further, if only
because we check it linearly (so with "m" local refs and "n" patterns,
we do "m * n" string comparisons). But if we care about optimizing this,
an even better solution may be a more advanced data structure anyway.

I didn't bother making the limit configurable, since it's so high and
since Git should behave correctly in either case. It wouldn't be too
hard to do, but it makes both the code and documentation more complex.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-15 12:25:19 -07:00
Taylor Blau
97b89c8150 p5326: don't set core.multiPackIndex unnecessarily
When this performance test was originally written, `core.multiPackIndex`
was not the default and thus had to be enabled. But now that we have
18e449f86b (midx: enable core.multiPackIndex by default, 2020-09-25), we
no longer need this.

Drop the unnecessary setup (even though it's not hurting anything, it is
unnecessary at best and confusing at worst).

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-14 16:34:18 -07:00
Taylor Blau
2082224f17 p5326: create missing 'perf-tag' tag
Some of the tests in test_full_bitmap rely on having a tag named
perf-tag in place. We could create it in test_full_bitmap(), but we want
to have it in place before the repack starts.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-14 16:34:18 -07:00
Taylor Blau
a05f02b1d9 t/helper/test-bitmap.c: add 'dump-hashes' mode
The pack-bitmap writer code is about to learn how to propagate values
from an existing hash-cache. To prepare, teach the test-bitmap helper to
dump the values from a bitmap's hash-cache extension in order to test
those changes.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-14 16:34:17 -07:00
Junio C Hamano
0057847208 Merge branch 'ab/serve-cleanup' into jk/reduce-malloc-in-v2-servers
* ab/serve-cleanup:
  upload-pack: document and rename --advertise-refs
  serve.[ch]: remove "serve_options", split up --advertise-refs code
  {upload,receive}-pack tests: add --advertise-refs tests
  serve.c: move version line to advertise_capabilities()
  serve: move transfer.advertiseSID check into session_id_advertise()
  serve.[ch]: don't pass "struct strvec *keys" to commands
  serve: use designated initializers
  transport: use designated initializers
  transport: rename "fetch" in transport_vtable to "fetch_refs"
  serve: mark has_capability() as static
2021-09-14 10:56:05 -07:00
Matthias Aßhauer
a3952f8e7c help: make sure local html page exists before calling external processes
We check that git.html exists, regardless of the page the user wants to open.
Checking whether the requested page exists instead gives us a smoother user
experience in two use cases:

1) The requested page doesn't exist

When calling a git command and there is an error, most users reasonably expect
git to produce an error message on the standard error stream, but in this case
we pass the filepath to git web--browse which passes it on to a browser (or a
helper program like xdg-open or start that should in turn open a browser)
without any error and many GUI based browsers or helpers won't output such a
message onto the standard error stream.

Especially the helper programs tend to show the corresponding error message in
a message box and wait for user input before exiting. This leaves users in
interactive console sessions without an error message in their console,
without a console prompt and without the help page they expected.

2) git.html is missing for some reason, but the user asked for some other page

We currently refuse to show any local html help page when we can't find
git.html. Even if the requested help page exists. If we check for the requested
page instead, we can show the user all available pages and only error out on
those that don't exist.

Signed-off-by: Matthias Aßhauer <mha1993@live.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-14 10:04:08 -07:00