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73835 Commits

Author SHA1 Message Date
Patrick Steinhardt
9c076c32fb pretty: add casts for decoration option pointers
The `struct decoration_options` have a prefix and suffix field which are
both non-constant, but we assign a constant pointer to them. This is
safe to do because we pass them to `format_decorations()`, which never
modifies these pointers, and then immediately discard the structure. Add
explicit casts to avoid compilation warnings with `-Wwrite-strings`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:30:52 -07:00
Patrick Steinhardt
9f03e4813a object-file: make buf parameter of index_mem() a constant
The `buf` parameter of `index_mem()` is a non-constant string. This will
break once we enable `-Wwrite-strings` because we also pass constants
from at least one callsite.

Adapt the parameter to be a constant. As we cannot free the buffer
without casting now, this also requires us to move the lifetime of the
nested buffer around.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:30:52 -07:00
Patrick Steinhardt
724b6d1e18 object-file: mark cached object buffers as const
The buffers of cached objects are never modified, but are still stored
as a non-constant pointer. This will cause a compiler warning once we
enable the `-Wwrite-strings` compiler warning as we assign an empty
constant string when initializing the static `empty_tree` cached object.

Convert the field to be constant. This requires us to shuffle around
the code a bit because we memcpy(3P) into the allocated buffer in
`pretend_object_file()`. This is easily fixed though by allocating the
buffer into a temporary variable first.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:30:51 -07:00
Patrick Steinhardt
32f9929109 ident: add casts for fallback name and GECOS
In `xgetpwuid_self()`, we return a fallback identity when it was not
possible to look up the current identity. This fallback identity needs
to be internal and must never be written to by the calles as specified
by getpwuid(3P). As both the `pw_name` and `pw_gecos` fields are marked
as non-constant though, it will cause a warning to assign constant
strings to them once compiling with `-Wwrite-strings`.

Add explicit casts to avoid the warning.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:30:51 -07:00
Patrick Steinhardt
b31607a3e0 entry: refactor how we remove items for delayed checkouts
When finalizing a delayed checkout, we sort out several strings from the
passed-in string list by first assigning the empty string to those
filters and then calling `string_list_remove_empty_items()`. Assigning
the empty string will cause compiler warnings though as the string is
a `char *` once we enable `-Wwrite-strings`.

Refactor the code to use a `NULL` pointer with `filter_string_list()`
instead to avoid this warning.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:30:51 -07:00
Patrick Steinhardt
394affd46d line-log: always allocate the output prefix
The returned string by `output_prefix()` is sometimes a string constant
and sometimes an allocated string. This has been fine until now because
we always leak the allocated strings, and thus we never tried to free
the string constant.

Fix the code to always return an allocated string and free the returned
value at all callsites.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:30:51 -07:00
Patrick Steinhardt
42d2ad5556 line-log: stop assigning string constant to file parent buffer
Stop assigning a string constant to the file parent buffer and instead
assign an allocated string. While the code is fine in practice, it will
break once we compile with `-Wwrite-strings`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:30:50 -07:00
Patrick Steinhardt
86badd4d0a diff: cast string constant in fill_textconv()
The `fill_textconv()` function is responsible for converting an input
file with a textconv driver, which is then passed to the caller. Weirdly
though, the function also handles the case where there is no textconv
driver at all. In that case, it will return either the contents of the
populated filespec, or an empty string if the filespec is invalid.

These two cases have differing memory ownership semantics. When there is
a textconv driver, then the result is an allocated string. Otherwise,
the result is either a string constant or owned by the filespec struct.
All callers are in fact aware of this weirdness and only end up freeing
the output buffer when they had a textconv driver.

Ideally, we'd split up this interface to only perform the conversion via
the textconv driver, and BUG in case the caller didn't provide one. This
would make memory ownership semantics much more straight forward. For
now though, let's simply cast the empty string constant to `char *` to
avoid a warning with `-Wwrite-strings`. This is equivalent to the same
cast that we already have in `fill_mmfile()`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:30:50 -07:00
Patrick Steinhardt
81654d27bf builtin/remote: cast away constness in get_head_names()
In `get_head_names()`, we assign the "refs/heads/*" string constant to
`struct refspec_item::{src,dst}`, which are both non-constant pointers.
Ideally, we'd refactor the code such that both of these fields were
constant. But `struct refspec_item` is used for two different usecases
with conflicting requirements:

  - To query for a source or destination based on the given refspec. The
    caller either sets `src` or `dst` as the branch that we want to
    search for, and the respective other field gets populated. The
    fields should be constant when being used as a query parameter,
    which is owned by the caller, and non-constant when being used as an
    out parameter, which is owned by the refspec item. This is is
    contradictory in itself already.

  - To store refspec items with their respective source and destination
    branches, in which case both fields should be owned by the struct.

Ideally, we'd split up this interface to clearly separate between
querying and storing, which would enable us to clarify lifetimes of the
strings. This would be a much bigger undertaking though.

Instead, accept the status quo for now and cast away the constness of
the source and destination patterns. We know that those are not being
written to or freed, so while this is ugly it certainly is fine for now.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:30:50 -07:00
Patrick Steinhardt
235ac3f81a refspec: remove global tag refspec structure
We have a global tag refspec structure that is used by both git-clone(1)
and git-fetch(1). Initialization of the structure will break once we
enable `-Wwrite-strings`, even though the breakage is harmless. While we
could just add casts, the structure isn't really required in the first
place as we can simply initialize the structures at the respective
callsites.

Refactor the code accordingly.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:30:49 -07:00
Patrick Steinhardt
66f892bb07 reftable: cast away constness when assigning constants to records
The reftable records are used in multiple ways throughout the reftable
library. In many of those cases they merely act as input to a function
without getting modified by it at all. Most importantly, this happens
when writing records and when querying for records.

We rely on this in our tests and thus assign string constants to those
fields, which is about to generate warnings as those fields are of type
`char *`. While we could go through the process and instead allocate
those strings in all of our tests, this feels quite unnecessary.

Instead, add casts to `char *` for all of those strings. As this is part
of our tests, this also nicely serves as a demonstration that nothing
writes or frees those string constants, which would otherwise lead to
segfaults.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:30:49 -07:00
Patrick Steinhardt
23c32511b3 refs/reftable: stop micro-optimizing refname allocations on copy
When copying refs, we execute `write_copy_table()` to write the new
table. As the names are given to us via `arg->newname` and
`arg->oldname`, respectively, we optimize away some allocations by
assigning those fields to the reftable records we are about to write
directly, without duplicating them. This requires us to cast the input
to `char *` pointers as they are in fact constant strings. Later on, we
then unset the refname for all of the records before calling
`reftable_log_record_release()` on them.

We also do this when assigning the "HEAD" constant, but here we do not
cast because its type is `char[]` by default. It's about to be turned
into `const char *` though once we enable `-Wwrite-strings` and will
thus cause another warning.

It's quite dubious whether this micro-optimization really helps. We're
about to write to disk anyway, which is going to be way slower than a
small handful of allocations. Let's drop the optimization altogther and
instead copy arguments to simplify the code and avoid the future warning
with `-Wwrite-strings`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:30:48 -07:00
Patrick Steinhardt
c113c5df79 global: convert intentionally-leaking config strings to consts
There are multiple cases where we intentionally leak config strings:

  - `struct gpg_format` is used to track programs that can be used for
    signing commits, either via gpg(1), gpgsm(1) or ssh-keygen(1). The
    user can override the commands via several config variables. As the
    array is populated once, only, and the struct memers are never
    written to or free'd.

  - `struct ll_merge_driver` is used to track merge drivers. Same as
    with the GPG format, these drivers are populated once and then
    reused. Its data is never written to or free'd, either.

  - `struct userdiff_funcname` and `struct userdiff_driver` can be
    configured via `diff.<driver>.*` to add additional drivers. Again,
    these have a global lifetime and are never written to or free'd.

All of these are intentionally kept alive and are never written to.
Furthermore, all of these are being assigned both string constants in
some places, and allocated strings in other places. This will cause
warnings once we enable `-Wwrite-strings`, so let's mark the respective
fields as `const char *` and cast away the constness when assigning
those values.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:30:48 -07:00
Patrick Steinhardt
b567004b4b global: improve const correctness when assigning string constants
We're about to enable `-Wwrite-strings`, which changes the type of
string constants to `const char[]`. Fix various sites where we assign
such constants to non-const variables.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:30:48 -07:00
Karthik Nayak
7dd4051b01 update-ref: add support for 'symref-update' command
Add 'symref-update' command to the '--stdin' mode of 'git-update-ref' to
allow updates of symbolic refs. The 'symref-update' command takes in a
<new-target>, which the <ref> will be updated to. If the <ref> doesn't
exist it will be created.

It also optionally takes either an `ref <old-target>` or `oid
<old-oid>`. If the <old-target> is provided, it checks to see if the
<ref> targets the <old-target> before the update. If <old-oid> is provided
it checks <ref> to ensure that it is a regular ref and <old-oid> is the
OID before the update. This by extension also means that this when a
zero <old-oid> is provided, it ensures that the ref didn't exist before.

The divergence in syntax from the regular `update` command is because if
we don't use a `(ref | oid)` prefix for the old_value, then there is
ambiguity around if the value provided should be treated as an oid or a
reference. This is more so the reason, because we allow anything
committish to be provided as an oid. While 'symref-verify' and
'symref-delete' also take in `<old-target>` we do not have this
divergence there as those commands only work with symrefs. Whereas
'symref-update' also works with regular refs and allows users to convert
regular refs to symrefs.

The command allows users to perform symbolic ref updates within a
transaction. This provides atomicity and allows users to perform a set
of operations together.

This command supports deref mode, to ensure that we can update
dereferenced regular refs to symrefs.

Helped-by: Patrick Steinhardt <ps@pks.im>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:25:45 -07:00
Karthik Nayak
f1dcdd6deb reftable: pick either 'oid' or 'target' for new updates
When creating a reference transaction update, we can provide the old/new
oid/target for the update. We have checks in place to ensure that for
each old/new, either oid or target is set and not both.

In the reftable backend, when dealing with updates without the
`REF_NO_DEREF` flag, we don't selectively propagate data as needed.
Since there are no active users of the path, this is not caught. As we
want to introduce the 'symref-update' command in the upcoming commit,
which would use this flow, correct it.

Helped-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:25:45 -07:00
Karthik Nayak
ed3272720e update-ref: add support for 'symref-create' command
Add 'symref-create' command to the '--stdin' mode 'git-update-ref' to
allow creation of symbolic refs in a transaction. The 'symref-create'
command takes in a <new-target>, which the created <ref> will point to.

Also, support the 'core.prefersymlinkrefs' config, wherein if the config
is set and the filesystem supports symlinks, we create the symbolic ref
as a symlink. We fallback to creating a regular symref if creating the
symlink is unsuccessful.

Helped-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:25:45 -07:00
Karthik Nayak
2343720967 update-ref: add support for 'symref-delete' command
Add a new command 'symref-delete' to allow deletions of symbolic refs in
a transaction via the '--stdin' mode of the 'git-update-ref' command.
The 'symref-delete' command can, when given an <old-target>, delete the
provided <ref> only when it points to <old-target>.

This command is only compatible with the 'no-deref' mode because we
optionally want to check the 'old_target' of the ref being deleted.
De-referencing a symbolic ref would provide a regular ref and we already
have the 'delete' command for regular refs.

While users can also use 'git symbolic-ref -d' to delete symbolic refs,
the 'symref-delete' command in 'git-update-ref' allows users to do so
within a transaction, which promises atomicity of the operation and can
be batched with other commands.

When no 'old_target' is provided it can also delete regular refs,
similar to how the 'delete' command can delete symrefs when no 'old_oid'
is provided.

Helped-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:25:44 -07:00
Karthik Nayak
1451ac734f update-ref: add support for 'symref-verify' command
The 'symref-verify' command allows users to verify if a provided <ref>
contains the provided <old-target> without changing the <ref>. If
<old-target> is not provided, the command will verify that the <ref>
doesn't exist.

The command allows users to verify symbolic refs within a transaction,
and this means users can perform a set of changes in a transaction only
when the verification holds good.

Since we're checking for symbolic refs, this command will only work with
the 'no-deref' mode. This is because any dereferenced symbolic ref will
point to an object and not a ref and the regular 'verify' command can be
used in such situations.

Add required tests for symref support in 'verify'. Since we're here,
also add reflog checks for the pre-existing 'verify' tests, there is no
divergence from behavior, but we never tested to ensure that reflog
wasn't affected by the 'verify' command.

Helped-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:25:44 -07:00
Karthik Nayak
aa6e99f122 refs: specify error for regular refs with old_target
When a reference update tries to update a symref, but the ref in
question is actually a regular ref, we raise an error. However the error
raised in this situation is:

  verifying symref target: '<ref>': reference is missing but expected <old-target>

which is very generic and doesn't indicate the mismatch of types. Let's
make this error more specific:

  cannot lock ref '<ref>': expected symref with target '<old-target>': but is a regular ref

so that users have a clearer understanding.

Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:25:44 -07:00
Karthik Nayak
aba381c090 refs: create and use ref_update_expects_existing_old_ref()
The files and reftable backend, need to check if a ref must exist, so
that the required validation can be done. A ref must exist only when the
`old_oid` value of the update has been explicitly set and it is not the
`null_oid` value.

Since we also support symrefs now, we need to ensure that even when
`old_target` is set a ref must exist. While this was missed when we
added symref support in transactions, there are no active users of this
path. As we introduce the 'symref-verify' command in the upcoming
commits, it is important to fix this.

So let's export this to a function called
`ref_update_expects_existing_old_ref()` and expose it internally via
'refs-internal.h'.

Helped-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 10:25:44 -07:00
Taylor Blau
8981dca8bc server-info.c: remove temporary info files on exit
The update_info_file() function within server-info.c is responsible for
moving the info/refs and info/packs files around when updating server
info.

These updates are staged into a temporary file and then moved into place
atomically to avoid race conditions when reading those files. However,
the temporary file used to stage these changes is managed outside of the
tempfile.h API, and thus survives process death.

Manage these files instead with the tempfile.h API so that they are
automatically cleaned up upon abnormal process death.

Unfortunately, and unlike in the previous step, there isn't a
straightforward way to inject a failure into the update-server-info step
that causes us to die() rather than take the cleanup path in label
'out', hence the lack of a test here.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 08:40:50 -07:00
Taylor Blau
c195ecda77 commit-graph.c: remove temporary graph layers on exit
Since the introduction of split commit graph layers in 92b1ea66b9a
(Merge branch 'ds/commit-graph-incremental', 2019-07-19), the function
write_commit_graph_file() has done the following when writing an
incremental commit-graph layer:

  - used a lock_file to control access to the commit-graph-chain file

  - used an auxiliary file (whose descriptor was stored in 'fd') to
    write the new commit-graph layer itself

Using a lock_file to control access to the commit-graph-chain is
sensible, since only one writer may modify it at a time. Likewise, when
the commit-graph machinery is writing out a single layer, the lock_file
structure is used to modify the commit-graph itself. This is also
sensible, since the non-incremental commit-graph may also have at most
one writer.

However, using an auxiliary temporary file without using the tempfile.h
API means that writes that fail after the temporary graph layer has been
created will leave around a file in

    $GIT_DIR/objects/info/commit-graphs/tmp_graph_XXXXXX

The commit-graph-chain file and non-incremental commit-graph do not
suffer from this problem as the lockfile.h API uses the tempfile.h API
transparently, so processes that died before moving those finals into
their final location cleaned up after themselves.

Ensure that the temporary file used to write incremental commit-graphs
is also managed with the tempfile.h API, to ensure that we do not ever
leave tmp_graph_XXXXXX files laying around.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-07 08:40:48 -07:00
Junio C Hamano
cd77e87115 The eleventh batch
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 12:49:25 -07:00
Junio C Hamano
9d8e7d2ef7 Merge branch 'mt/openindiana-scalar'
Avoid removing the $(cwd) for portability.

* mt/openindiana-scalar:
  scalar: make enlistment delete to work on all POSIX platforms
2024-06-06 12:49:25 -07:00
Junio C Hamano
df5c2c4962 Merge branch 'rs/difftool-env-simplify'
Code simplification.

* rs/difftool-env-simplify:
  difftool: add env vars directly in run_file_diff()
2024-06-06 12:49:24 -07:00
Junio C Hamano
d11b0c75ec Merge branch 'th/quiet-lazy-fetch-from-promisor'
The promisor.quiet configuration knob can be set to true to make
lazy fetching from promisor remotes silent.

* th/quiet-lazy-fetch-from-promisor:
  promisor-remote: add promisor.quiet configuration option
2024-06-06 12:49:24 -07:00
Junio C Hamano
cf792653ad Merge branch 'ps/leakfixes'
Leakfixes.

* ps/leakfixes:
  builtin/mv: fix leaks for submodule gitfile paths
  builtin/mv: refactor to use `struct strvec`
  builtin/mv duplicate string list memory
  builtin/mv: refactor `add_slash()` to always return allocated strings
  strvec: add functions to replace and remove strings
  submodule: fix leaking memory for submodule entries
  commit-reach: fix memory leak in `ahead_behind()`
  builtin/credential: clear credential before exit
  config: plug various memory leaks
  config: clarify memory ownership in `git_config_string()`
  builtin/log: stop using globals for format config
  builtin/log: stop using globals for log config
  convert: refactor code to clarify ownership of check_roundtrip_encoding
  diff: refactor code to clarify memory ownership of prefixes
  config: clarify memory ownership in `git_config_pathname()`
  http: refactor code to clarify memory ownership
  checkout: clarify memory ownership in `unique_tracking_name()`
  strbuf: fix leak when `appendwholeline()` fails with EOF
  transport-helper: fix leaking helper name
2024-06-06 12:49:23 -07:00
Aaron Plattner
27db485c34 credential: clear expired c->credential, unify secret clearing
When a struct credential expires, credential_fill() clears c->password
so that clients don't try to use it later. However, a struct cred that
uses an alternate authtype won't have a password, but might have a
credential stored in c->credential.

This is a problem, for example, when an OAuth2 bearer token is used. In
the system I'm using, the OAuth2 configuration generates and caches a
bearer token that is valid for an hour. After the token expires, git
needs to call back into the credential helper to use a stored refresh
token to get a new bearer token. But if c->credential is still non-NULL,
git will instead try to use the expired token and fail with an error:

 fatal: Authentication failed for 'https://<oauth2-enabled-server>/repository'

And on the server:

 [auth_openidc:error] [client <ip>:34012] oidc_proto_validate_exp: "exp" validation failure (1717522989): JWT expired 224 seconds ago

Fix this by clearing both c->password and c->credential for an expired
struct credential. While we're at it, use credential_clear_secrets()
wherever both c->password and c->credential are being cleared.

Update comments in credential.h to mention the new struct fields.

Signed-off-by: Aaron Plattner <aplattner@nvidia.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 11:42:40 -07:00
Jeff King
62c71ace44 test-terminal: drop stdin handling
Since 18d8c26930 (test_terminal: redirect child process' stdin to a pty,
2015-08-04), we set up a pty and copy stdin to the child program. But
this ends up being racy; once we send all of the bytes and close the
descriptor, the child program will no longer see a terminal! isatty()
will return 0, and trying to read may return EIO, even if we didn't yet
get all of the bytes.

This was mentioned even in the commit message of 18d8c26930, but we
hacked around it by just sending an infinite input from /dev/zero (in
the intended case, we only cared about isatty(0), not reading actual
input).

And it came up again recently in:

  https://lore.kernel.org/git/d42a55b1-1ba9-4cfb-9c3d-98ea4d86da33@gmail.com/

where we tried to actually send bytes, but they don't always all come
through. So this interface is somewhat of an accident waiting to happen;
a caller might not even care about stdin being a tty, but will get bit
by the flaky behavior.

One solution would probably be to avoid closing test_terminal's end of
the pty altogether. But then the other side would never see EOF on its
stdin.  That may be OK for some cases, but it's another gotcha that
might cause races or deadlocks, depending on what the child expects to
read.

Let's instead just drop test_terminal's stdin feature completely. Since
the previous commit dropped the two cases from t4153 for which the
feature was originally added, there are no callers left that need it.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 10:07:41 -07:00
Jeff King
53ce2e3f0a am: add explicit "--retry" option
After a patch fails, you can ask "git am" to try applying it again with
new options by running without any of the resume options. E.g.:

  git am <patch
  # oops, it failed; let's try again
  git am --3way

But since this second command has no explicit resume option (like
"--continue"), it looks just like an invocation to read a fresh patch
from stdin. To avoid confusing the two cases, there are some heuristics,
courtesy of 8d18550318 (builtin-am: reject patches when there's a
session in progress, 2015-08-04):

	if (in_progress) {
		/*
		 * Catch user error to feed us patches when there is a session
		 * in progress:
		 *
		 * 1. mbox path(s) are provided on the command-line.
		 * 2. stdin is not a tty: the user is trying to feed us a patch
		 *    from standard input. This is somewhat unreliable -- stdin
		 *    could be /dev/null for example and the caller did not
		 *    intend to feed us a patch but wanted to continue
		 *    unattended.
		 */
		if (argc || (resume_mode == RESUME_FALSE && !isatty(0)))
			die(_("previous rebase directory %s still exists but mbox given."),
				state.dir);

		if (resume_mode == RESUME_FALSE)
			resume_mode = RESUME_APPLY;
		[...]

So if no resume command is given, then we require that stdin be a tty,
and otherwise complain about (potentially) receiving an mbox on stdin.
But of course you might not actually have a terminal available! And
sadly there is no explicit way to hit this same code path; this is the
only place that sets RESUME_APPLY. So you're stuck, and scripts like our
test suite have to bend over backwards to create a pseudo-tty.

Let's provide an explicit option to trigger this mode. The code turns
out to be quite simple; just setting "resume_mode" to RESUME_FALSE is
enough to dodge the tty check, and then our state is the same as it
would be with the heuristic case (which we'll continue to allow).

When we don't have a session in progress, there's already code to
complain when resume_mode is set (but we'll add a new test to cover
that).

To test the new option, we'll convert the existing tests that rely on
the fake stdin tty. That lets us test them on more platforms, and will
let us simplify test_terminal a bit in a future patch.

It does, however, mean we're not testing the tty heuristic at all.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 10:07:41 -07:00
Patrick Steinhardt
df651330ab ci: fix check for Ubuntu 20.04
In 5ca0c455f1 (ci: fix Python dependency on Ubuntu 24.04, 2024-05-06),
we made the use of Python 2 conditional on whether or not the CI job
runs Ubuntu 20.04. There was a brown-paper-bag-style bug though, where
the condition forgot to invoke the `test` builtin. The result of it is
that the check always fails, and thus all of our jobs run with Python 3
by accident.

Fix this.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:59:27 -07:00
Patrick Steinhardt
25a0023f28 builtin/refs: new command to migrate ref storage formats
Introduce a new command that allows the user to migrate a repository
between ref storage formats. This new command is implemented as part of
a new git-refs(1) executable. This is due to two reasons:

  - There is no good place to put the migration logic in existing
    commands. git-maintenance(1) felt unwieldy, and git-pack-refs(1) is
    not the correct place to put it, either.

  - I had it in my mind to create a new low-level command for accessing
    refs for quite a while already. git-refs(1) is that command and can
    over time grow more functionality relating to refs. This should help
    discoverability by consolidating low-level access to refs into a
    single executable.

As mentioned in the preceding commit that introduces the ref storage
format migration logic, the new `git refs migrate` command still has a
bunch of restrictions. These restrictions are documented accordingly.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:04:34 -07:00
Patrick Steinhardt
6d6a3a99c7 refs: implement logic to migrate between ref storage formats
With the introduction of the new "reftable" backend, users may want to
migrate repositories between the backends without having to recreate the
whole repository. Add the logic to do so.

The implementation is generic and works with arbitrary ref storage
formats so that a backend does not need to implement any migration
logic. It does have a few limitations though:

  - We do not migrate repositories with worktrees, because worktrees
    have separate ref storages. It makes the overall affair more complex
    if we have to migrate multiple storages at once.

  - We do not migrate reflogs, because we have no interfaces to write
    many reflog entries.

  - We do not lock the repository for concurrent access, and thus
    concurrent writes may end up with weird in-between states. There is
    no way to fully lock the "files" backend for writes due to its
    format, and thus we punt on this topic altogether and defer to the
    user to avoid those from happening.

In other words, this version is a minimum viable product for migrating a
repository's ref storage format. It works alright for bare repos, which
often have neither worktrees nor reflogs. But it will not work for many
other repositories without some preparations. These limitations are not
set into stone though, and ideally we will eventually address them over
time.

The logic is not yet used by anything, and thus there are no tests for
it. Those will be added in the next commit.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:04:33 -07:00
Patrick Steinhardt
64a6dd8ffc refs: implement removal of ref storages
We're about to introduce logic to migrate ref storages. One part of the
migration will be to delete the files that are part of the old ref
storage format. We don't yet have a way to delete such data generically
across ref backends though.

Implement a new `delete` callback and expose it via a new
`ref_storage_delete()` function.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:04:33 -07:00
Patrick Steinhardt
1339cb3c47 worktree: don't store main worktree twice
In `get_worktree_ref_store()` we either return the repository's main ref
store, or we look up the ref store via the map of worktree ref stores.
Which of these worktrees gets picked depends on the `is_current` bit of
the worktree, which indicates whether the worktree is the one that
corresponds to `the_repository`.

The bit is getting set in `get_worktrees()`, but only after we have
computed the list of all worktrees. This is too late though, because at
that time we have already called `get_worktree_ref_store()` on each of
the worktrees via `add_head_info()`. The consequence is that the current
worktree will not have been marked accordingly, which means that we did
not use the main ref store, but instead created a new ref store. We thus
have two separate ref stores now that map to the same ref database.

Fix this by setting `is_current` before we call `add_head_info()`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:04:33 -07:00
Patrick Steinhardt
b5d7db9e83 reftable: inline merged_table_release()
The function `merged_table_release()` releases a merged table, whereas
`reftable_merged_table_free()` releases a merged table and then also
free's its pointer. But all callsites of `merged_table_release()` are in
fact followed by `reftable_merged_table_free()`, which is redundant.

Inline `merged_table_release()` into `reftable_merged_table_free()` to
get rid of this redundance.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:04:32 -07:00
Patrick Steinhardt
b3e098d6e7 refs/files: fix NULL pointer deref when releasing ref store
The `free_ref_cache()` function is not `NULL` safe and will thus
segfault when being passed such a pointer. This can easily happen when
trying to release a partially initialized "files" ref store. Fix this.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:04:32 -07:00
Patrick Steinhardt
120b67172f refs/files: extract function to iterate through root refs
Extract a new function that can be used to iterate through all root refs
known to the "files" backend. This will be used in the next commit,
where we start to teach ref backends to remove themselves.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:04:32 -07:00
Patrick Steinhardt
66275a6311 refs/files: refactor add_pseudoref_and_head_entries()
The `add_pseudoref_and_head_entries()` function accepts both the ref
store as well as a directory name as input. This is unnecessary though
as the ref store already uniquely identifies the root directory of the
ref store anyway.

Furthermore, the function is misnamed now that we have clarified the
meaning of pseudorefs as it doesn't add pseudorefs, but root refs.
Rename it accordingly.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:04:32 -07:00
Patrick Steinhardt
fbd1a693c7 refs: allow to skip creation of reflog entries
The ref backends do not have any way to disable the creation of reflog
entries. This will be required for upcoming ref format migration logic
so that we do not create any entries that didn't exist in the original
ref database.

Provide a new `REF_SKIP_CREATE_REFLOG` flag that allows the caller to
disable reflog entry creation.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:04:31 -07:00
Patrick Steinhardt
6e1683ace9 refs: pass storage format to ref_store_init() explicitly
We're about to introduce logic to migrate refs from one storage format
to another one. This will require us to initialize a ref store with a
different format than the one used by the passed-in repository.

Prepare for this by accepting the desired ref storage format as
parameter.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:04:31 -07:00
Patrick Steinhardt
318efb966b refs: convert ref storage format to an enum
The ref storage format is tracked as a simple unsigned integer, which
makes it harder than necessary to discover what that integer actually is
or where its values are defined.

Convert the ref storage format to instead be an enum.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:04:31 -07:00
Patrick Steinhardt
a83f7f51e1 setup: unset ref storage when reinitializing repository version
When reinitializing a repository's version we may end up unsetting the
hash algorithm when it matches the default hash algorithm. If we didn't
do that then the previously configured value might remain intact.

While the same issue exists for the ref storage extension, we don't do
this here. This has been fine for most of the part because it is not
supported to re-initialize a repository with a different ref storage
format anyway. We're about to introduce a new command to migrate ref
storages though, so this is about to become an issue there.

Prepare for this and unset the ref storage format when reinitializing a
repository with the "files" format.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 09:04:31 -07:00
Patrick Steinhardt
f60fec6a16 ci/test-documentation: work around SyntaxWarning in Python 3.12
In Python 3.6, unrecognized escape sequences in regular expressions
started to produce a DeprecationWarning [1]. In Python 3.12, this was
upgraded to a SyntaxWarning and will eventually be raised even further
to a SyntaxError. We indirectly hit such unrecognized escape sequences
via Asciidoc, which results in a bunch of warnings:

    $ asciidoc -o /dev/null git-cat-file.txt
    <unknown>:1: SyntaxWarning: invalid escape sequence '\S'
    <unknown>:1: SyntaxWarning: invalid escape sequence '\S'

This in turn causes our "ci/test-documentation.sh" script to fail, as it
checks that stderr of `make doc` is empty.

These escape sequences seem to be part of Asciidoc itself. In the long
term, we should probably consider dropping support for Asciidoc in favor
of Asciidoctor. Upstream also considers itself to be legacy software and
recommends to move away from it [2]:

    It is suggested that unless you specifically require the AsciiDoc.py
    toolchain, you should find a processor that handles the modern
    AsciiDoc syntax.

For now though, let's expand its lifetime a little bit more by filtering
out these new warnings. We should probably reconsider once the warnings
are upgraded to errors by Python.

[1]: https://docs.python.org/3/reference/lexical_analysis.html#string-and-bytes-literals
[2]: 6d9f76cff0/README.md (asciidocpy)

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 08:20:51 -07:00
Patrick Steinhardt
401151de9e gitlab-ci: add job to run make check-docs
Add another job to execute `make check-docs`, which lints our
documentation and makes sure that expected manpages exist. This job
mirrors the same job that we already have for GitHub Actions.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 08:20:51 -07:00
Patrick Steinhardt
6423920974 Documentation/lint-manpages: bubble up errors
The "lint-manpages.sh" script does not return an error in case any of
its checks fail. While this is faithful to the implementation that we
had as part of the "check-docs" target before the preceding commit, it
makes it hard to spot any violations of the rules via the corresponding
CI job, which will of course exit successfully, too.

Adapt the script to bubble up errors.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 08:20:51 -07:00
Patrick Steinhardt
2dd100c513 Makefile: extract script to lint missing/extraneous manpages
The "check-docs" target of our top-level Makefile fulfills two different
roles. For one it runs the "lint-docs" target of the "Documentation/"
Makefile. And second it performs some checks of whether there are any
manpages that are missing or extraneous via some inline scripts.

The second set of checks feels quite misplaced in the top-level Makefile
as it would fit in much better with our "lint-docs" target. Back when
the checks were introduced in 8c989ec528 (Makefile: $(MAKE) check-docs,
2006-04-13), that target did not yet exist though.

Furthermore, the script makes use of several Makefile variables which
are defined in the top-level Makefile, which makes it hard to access
their contents from elsewhere. There is a trick though that we already
use in "check-builtins.sh" to gain access: we can create an ad-hoc
Makefile that has an extra target to print those variables.

Pull out the script into a separate "lint-manpages.sh" script by using
that trick. Wire up that script via the "lint-docs" target. For one,
normal shell scripts are way easier to reason about than those which are
embedded in a Makefile. Second, it allows one to easily execute the
script standalone without any of the other checks.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-06 08:20:50 -07:00
Junio C Hamano
a74c0686fa add-i: finally retire add.interactive.useBuiltin
The configuration variable stopped doing anything (other than
announcing itself as a variable that does not do anything useful,
when it is used) in Git 2.40.

At this point, it is not even worth giving the warning, which was
meant to be a way to help users notice they are carrying unused
cruft in their configuration files and give them a chance to
clean-up.

Let's remove the warning and documentation for it, and truly stop
paying attention to it.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
               ---
 Documentation/config/add.txt |  6 ------
 builtin/add.c                |  6 +-----
 t/t3701-add-interactive.sh   | 15 ---------------
 3 files changed, 1 insertion(+), 26 deletions(-)
2024-06-05 14:53:26 -07:00
Junio C Hamano
5c71d6b63a attr.tree: HEAD:.gitattributes is no longer the default in a bare repo
51441e64 (stop using HEAD for attributes in bare repository by
default, 2024-05-03) has addressed a recent performance regression
by partially reverting a topic that was merged at 26dd307c (Merge
branch 'jc/attr-tree-config', 2023-10-30).  But it forgot to update
the documentation to remove the mention of a special case in bare
repositories.

Let's update the document before the update hits the next release.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-06-05 14:52:53 -07:00