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Author SHA1 Message Date
Glen Choo a4e7e317f8 config: add ctx arg to config_fn_t
Add a new "const struct config_context *ctx" arg to config_fn_t to hold
additional information about the config iteration operation.
config_context has a "struct key_value_info kvi" member that holds
metadata about the config source being read (e.g. what kind of config
source it is, the filename, etc). In this series, we're only interested
in .kvi, so we could have just used "struct key_value_info" as an arg,
but config_context makes it possible to add/adjust members in the future
without changing the config_fn_t signature. We could also consider other
ways of organizing the args (e.g. moving the config name and value into
config_context or key_value_info), but in my experiments, the
incremental benefit doesn't justify the added complexity (e.g. a
config_fn_t will sometimes invoke another config_fn_t but with a
different config value).

In subsequent commits, the .kvi member will replace the global "struct
config_reader" in config.c, making config iteration a global-free
operation. It requires much more work for the machinery to provide
meaningful values of .kvi, so for now, merely change the signature and
call sites, pass NULL as a placeholder value, and don't rely on the arg
in any meaningful way.

Most of the changes are performed by
contrib/coccinelle/config_fn_ctx.pending.cocci, which, for every
config_fn_t:

- Modifies the signature to accept "const struct config_context *ctx"
- Passes "ctx" to any inner config_fn_t, if needed
- Adds UNUSED attributes to "ctx", if needed

Most config_fn_t instances are easily identified by seeing if they are
called by the various config functions. Most of the remaining ones are
manually named in the .cocci patch. Manual cleanups are still needed,
but the majority of it is trivial; it's either adjusting config_fn_t
that the .cocci patch didn't catch, or adding forward declarations of
"struct config_context ctx" to make the signatures make sense.

The non-trivial changes are in cases where we are invoking a config_fn_t
outside of config machinery, and we now need to decide what value of
"ctx" to pass. These cases are:

- trace2/tr2_cfg.c:tr2_cfg_set_fl()

  This is indirectly called by git_config_set() so that the trace2
  machinery can notice the new config values and update its settings
  using the tr2 config parsing function, i.e. tr2_cfg_cb().

- builtin/checkout.c:checkout_main()

  This calls git_xmerge_config() as a shorthand for parsing a CLI arg.
  This might be worth refactoring away in the future, since
  git_xmerge_config() can call git_default_config(), which can do much
  more than just parsing.

Handle them by creating a KVI_INIT macro that initializes "struct
key_value_info" to a reasonable default, and use that to construct the
"ctx" arg.

Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-06-28 14:06:39 -07:00
Junio C Hamano a9ea4c23dc Merge branch 'ps/cat-file-null-output'
"git cat-file --batch" and friends learned "-Z" that uses NUL
delimiter for both input and output.

* ps/cat-file-null-output:
  cat-file: add option '-Z' that delimits input and output with NUL
  cat-file: simplify reading from standard input
  strbuf: provide CRLF-aware helper to read until a specified delimiter
  t1006: modernize test style to use `test_cmp`
  t1006: don't strip timestamps from expected results
2023-06-22 16:29:06 -07:00
Derrick Stolee d24eda4e03 repository: create disable_replace_refs()
Several builtins depend on being able to disable the replace references
so we actually operate on each object individually. These currently do
so by directly mutating the 'read_replace_refs' global.

A future change will move this global into a different place, so it will
be necessary to change all of these lines. However, we can simplify that
transition by abstracting the purpose of these global assignments with a
method call.

We will need to keep this read_replace_refs global forever, as we want
to make sure that we never use replace refs throughout the life of the
process if this method is called. Future changes may present a
repository-scoped version of the variable to represent that repository's
core.useReplaceRefs config value, but a zero-valued read_replace_refs
will always override such a setting.

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-06-12 13:34:55 -07:00
Patrick Steinhardt f79e18849b cat-file: add option '-Z' that delimits input and output with NUL
In db9d67f2e9 (builtin/cat-file.c: support NUL-delimited input with
`-z`, 2022-07-22), we have introduced a new mode to read the input via
NUL-delimited records instead of newline-delimited records. This allows
the user to query for revisions that have newlines in their path
component. While unusual, such queries are perfectly valid and thus it
is clear that we should be able to support them properly.

Unfortunately, the commit only changed the input to be NUL-delimited,
but didn't change the output at the same time. While this is fine for
queries that are processed successfully, it is less so for queries that
aren't. In the case of missing commits for example the result can become
entirely unparsable:

```
$ printf "7ce4f05bae8120d9fa258e854a8669f6ea9cb7b1 blob 10\n1234567890\n\n\commit000" |
    git cat-file --batch -z
7ce4f05bae blob 10
1234567890

commit missing
```

This is of course a crafted query that is intentionally gaming the
deficiency, but more benign queries that contain newlines would have
similar problems.

Ideally, we should have also changed the output to be NUL-delimited when
`-z` is specified to avoid this problem. As the input is NUL-delimited,
it is clear that the output in this case cannot ever contain NUL
characters by itself. Furthermore, Git does not allow NUL characters in
revisions anyway, further stressing the point that using NUL-delimited
output is safe. The only exception is of course the object data itself,
but as git-cat-file(1) prints the size of the object data clients should
read until that specified size has been consumed.

But even though `-z` has only been introduced a few releases ago in Git
v2.38.0, changing the output format retroactively to also NUL-delimit
output would be a backwards incompatible change. And while one could
make the argument that the output is inherently broken already, we need
to assume that there are existing users out there that use it just fine
given that revisions containing newlines are quite exotic.

Instead, introduce a new option `-Z` that switches to NUL-delimited
input and output. While this new option could arguably only switch the
output format to be NUL-delimited, the consequence would be that users
have to always specify both `-z` and `-Z` when the input may contain
newlines. On the other hand, if the user knows that there never will be
newlines in the input, they don't have to use either of those options.
There is thus no usecase that would warrant treating input and output
format separately, which is why we instead opt to "do the right thing"
and have `-Z` mean to NUL-terminate both formats.

The old `-z` option is marked as deprecated with a hint that its output
may become unparsable. It is thus hidden both from the synopsis as well
as the command's help output.

Co-authored-by: Toon Claes <toon@iotcl.com>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-06-12 13:23:46 -07:00
Patrick Steinhardt 3217f52a49 cat-file: simplify reading from standard input
The batch modes of git-cat-file(1) read queries from stantard input that
are either newline- or NUL-delimited. This code was introduced via
db9d67f2e9 (builtin/cat-file.c: support NUL-delimited input with `-z`,
2022-07-22), which notes that:

"""
The refactoring here is slightly unfortunate, since we turn loops like:

     while (strbuf_getline(&buf, stdin) != EOF)

 into:

     while (1) {
         int ret;
         if (opt->nul_terminated)
             ret = strbuf_getline_nul(&input, stdin);
         else
             ret = strbuf_getline(&input, stdin);

         if (ret == EOF)
             break;
     }
"""

The commit proposed introducing a helper function that is easier to use,
which is just what we have done in the preceding commit. Refactor the
code to use this new helper to simplify the loop.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-06-12 13:23:24 -07:00
Elijah Newren 87bed17907 object-file.h: move declarations for object-file.c functions from cache.h
Signed-off-by: Elijah Newren <newren@gmail.com>
Acked-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-04-11 08:52:10 -07:00
Elijah Newren dabab1d6e6 object-name.h: move declarations for object-name.c functions from cache.h
Signed-off-by: Elijah Newren <newren@gmail.com>
Acked-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-04-11 08:52:09 -07:00
Elijah Newren 73359a9b43 treewide: be explicit about dependence on convert.h
Signed-off-by: Elijah Newren <newren@gmail.com>
Acked-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-04-11 08:52:09 -07:00
Junio C Hamano e7dca80692 Merge branch 'ab/remove-implicit-use-of-the-repository' into en/header-split-cache-h
* ab/remove-implicit-use-of-the-repository:
  libs: use "struct repository *" argument, not "the_repository"
  post-cocci: adjust comments for recent repo_* migration
  cocci: apply the "revision.h" part of "the_repository.pending"
  cocci: apply the "rerere.h" part of "the_repository.pending"
  cocci: apply the "refs.h" part of "the_repository.pending"
  cocci: apply the "promisor-remote.h" part of "the_repository.pending"
  cocci: apply the "packfile.h" part of "the_repository.pending"
  cocci: apply the "pretty.h" part of "the_repository.pending"
  cocci: apply the "object-store.h" part of "the_repository.pending"
  cocci: apply the "diff.h" part of "the_repository.pending"
  cocci: apply the "commit.h" part of "the_repository.pending"
  cocci: apply the "commit-reach.h" part of "the_repository.pending"
  cocci: apply the "cache.h" part of "the_repository.pending"
  cocci: add missing "the_repository" macros to "pending"
  cocci: sort "the_repository" rules by header
  cocci: fix incorrect & verbose "the_repository" rules
  cocci: remove dead rule from "the_repository.pending.cocci"
2023-04-04 08:25:52 -07:00
Ævar Arnfjörð Bjarmason a5183d7696 cocci: apply the "promisor-remote.h" part of "the_repository.pending"
Apply the part of "the_repository.pending.cocci" pertaining to
"promisor-remote.h".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-03-28 07:36:46 -07:00
Ævar Arnfjörð Bjarmason bc726bd075 cocci: apply the "object-store.h" part of "the_repository.pending"
Apply the part of "the_repository.pending.cocci" pertaining to
"object-store.h".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-03-28 07:36:45 -07:00
Elijah Newren d48be35ca6 write-or-die.h: move declarations for write-or-die.c functions from cache.h
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-03-21 10:56:54 -07:00
Elijah Newren 32a8f51061 environment.h: move declarations for environment.c functions from cache.h
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-03-21 10:56:53 -07:00
Elijah Newren f394e093df treewide: be explicit about dependence on gettext.h
Dozens of files made use of gettext functions, without explicitly
including gettext.h.  This made it more difficult to find which files
could remove a dependence on cache.h.  Make C files explicitly include
gettext.h if they are using it.

However, while compat/fsmonitor/fsm-ipc-darwin.c should also gain an
include of gettext.h, it was left out to avoid conflicting with an
in-flight topic.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-03-21 10:56:51 -07:00
Junio C Hamano d0732a8120 Merge branch 'jk/unused-post-2.39-part2'
More work towards -Wunused.

* jk/unused-post-2.39-part2: (21 commits)
  help: mark unused parameter in git_unknown_cmd_config()
  run_processes_parallel: mark unused callback parameters
  userformat_want_item(): mark unused parameter
  for_each_commit_graft(): mark unused callback parameter
  rewrite_parents(): mark unused callback parameter
  fetch-pack: mark unused parameter in callback function
  notes: mark unused callback parameters
  prio-queue: mark unused parameters in comparison functions
  for_each_object: mark unused callback parameters
  list-objects: mark unused callback parameters
  mark unused parameters in signal handlers
  run-command: mark error routine parameters as unused
  mark "pointless" data pointers in callbacks
  ref-filter: mark unused callback parameters
  http-backend: mark unused parameters in virtual functions
  http-backend: mark argc/argv unused
  object-name: mark unused parameters in disambiguate callbacks
  serve: mark unused parameters in virtual functions
  serve: use repository pointer to get config
  ls-refs: drop config caching
  ...
2023-03-17 14:03:09 -07:00
Jeff King be252d3349 for_each_object: mark unused callback parameters
The for_each_{loose,packed}_object interface uses callback functions,
but not every callback needs all of the parameters. Mark the unused ones
to satisfy -Wunused-parameter.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-24 09:13:31 -08:00
Elijah Newren cbeab74713 replace-object.h: move read_replace_refs declaration from cache.h to here
Adjust several files to be more explicit about their dependency on
replace-objects to accommodate this change.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-23 17:25:30 -08:00
Elijah Newren b5fa608180 ident.h: move ident-related declarations out of cache.h
These functions were all defined in a separate ident.c already, so
create ident.h and move the declarations into that file.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-23 17:25:29 -08:00
Elijah Newren 41771fa435 cache.h: remove dependence on hex.h; make other files include it explicitly
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-23 17:25:29 -08:00
Elijah Newren 36bf195890 alloc.h: move ALLOC_GROW() functions from cache.h
This allows us to replace includes of cache.h with includes of the much
smaller alloc.h in many places.  It does mean that we also need to add
includes of alloc.h in a number of C files.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-23 17:25:28 -08:00
Junio C Hamano 319c3abadb Merge branch 'sa/cat-file-mailmap--batch-check'
'cat-file' gains mailmap support for its '--batch-check' and '-s'
options.

* sa/cat-file-mailmap--batch-check:
  cat-file: add mailmap support to --batch-check option
  cat-file: add mailmap support to -s option
2023-01-05 15:07:17 +09:00
Siddharth Asthana a797c0ea04 cat-file: add mailmap support to --batch-check option
Even though the cat-file command with `--batch-check` option does not
complain when `--use-mailmap` option is given, the latter option is
ignored. Compute the size of the object after replacing the idents and
report it instead.

In order to make `--batch-check` option honour the mailmap mechanism we
have to read the contents of the commit/tag object.

There were two ways to do it:

1. Make two calls to `oid_object_info_extended()`. If `--use-mailmap`
   option is given, the first call will get us the type of the object
   and second call will only be made if the object type is either a
   commit or tag to get the contents of the object.

2. Make one call to `oid_object_info_extended()` to get the type of the
   object. Then, if the object type is either of commit or tag, make a
   call to `repo_read_object_file()` to read the contents of the object.

I benchmarked the following command with both the above approaches and
compared against the current implementation where `--use-mailmap`
option is ignored:

`git cat-file --use-mailmap --batch-all-objects --batch-check --buffer
--unordered`

The results can be summarized as follows:
                       Time (mean ± σ)
default               827.7 ms ± 104.8 ms
first approach        6.197 s ± 0.093 s
second approach       1.975 s ± 0.217 s

Since, the second approach is faster than the first one, I implemented
it in this patch.

The command git cat-file can now use the mailmap mechanism to replace
idents with canonical versions for commit and tag objects. There are
several options like `--batch`, `--batch-check` and `--batch-command`
that can be combined with `--use-mailmap`. But the documentation for
`--batch`, `--batch-check` and `--batch-command` doesn't say so. This
patch fixes that documentation.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: John Cai <johncai86@gmail.com>
Helped-by: Taylor Blau <me@ttaylorr.com>
Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Siddharth Asthana <siddharthasthana31@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-20 15:20:45 +09:00
Siddharth Asthana 49050a043b cat-file: add mailmap support to -s option
Even though the cat-file command with `-s` option does not complain when
`--use-mailmap` option is given, the latter option is ignored. Compute
the size of the object after replacing the idents and report it instead.

In order to make `-s` option honour the mailmap mechanism we have to
read the contents of the commit/tag object. Make use of the call to
`oid_object_info_extended()` to get the contents of the object and store
in `buf`. `buf` is later freed in the function.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: John Cai <johncai86@gmail.com>
Helped-by: Taylor Blau <me@ttaylorr.com>
Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Siddharth Asthana <siddharthasthana31@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-20 15:20:45 +09:00
Ævar Arnfjörð Bjarmason 666f53eb43 {builtin/*,repository}.c: add & use "USE_THE_INDEX_VARIABLE"
Split up the "USE_THE_INDEX_COMPATIBILITY_MACROS" into that setting
and a more narrow "USE_THE_INDEX_VARIABLE". In the case of these
built-ins we only need "the_index" variable, but not the compatibility
wrapper for functions we're not using.

Let's then have some users of "USE_THE_INDEX_COMPATIBILITY_MACROS" use
this more narrow and descriptive define.

For context: The USE_THE_INDEX_COMPATIBILITY_MACROS macro was added to
test-tool.h in f8adbec9fe (cache.h: flip
NO_THE_INDEX_COMPATIBILITY_MACROS switch, 2019-01-24).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason dfc833332a doc txt & -h consistency: add "-z" to cat-file "-h"
Fix a bug in db9d67f2e9 (builtin/cat-file.c: support NUL-delimited
input with `-z`, 2022-07-22), before that change the SYNOPSIS and "-h"
output were the same, but not afterwards.

That change followed a similar earlier divergence in
473fa2df08 (Documentation: add --batch-command to cat-file synopsis,
2022-04-07). Subsequent commits will fix this sort of thing more
systematically, but let's fix this one as a one-off.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-10-13 09:32:55 -07:00
Junio C Hamano 1e92768aa1 Merge branch 'tb/cat-file-z'
Operating modes like "--batch" of "git cat-file" command learned to
take NUL-terminated input, instead of one-item-per-line.

* tb/cat-file-z:
  builtin/cat-file.c: support NUL-delimited input with `-z`
  t1006: extract --batch-command inputs to variables
2022-08-05 15:52:14 -07:00
Junio C Hamano 87098a047b Merge branch 'sa/cat-file-mailmap'
"git cat-file" learned an option to use the mailmap when showing
commit and tag objects.

* sa/cat-file-mailmap:
  cat-file: add mailmap support
  ident: rename commit_rewrite_person() to apply_mailmap_to_header()
  ident: move commit_rewrite_person() to ident.c
  revision: improve commit_rewrite_person()
2022-08-03 13:36:08 -07:00
Taylor Blau db9d67f2e9 builtin/cat-file.c: support NUL-delimited input with `-z`
When callers are using `cat-file` via one of the stdin-driven `--batch`
modes, all input is newline-delimited. This presents a problem when
callers wish to ask about, e.g. tree-entries that have a newline
character present in their filename.

To support this niche scenario, introduce a new `-z` mode to the
`--batch`, `--batch-check`, and `--batch-command` suite of options that
instructs `cat-file` to treat its input as NUL-delimited, allowing the
individual commands themselves to have newlines present.

The refactoring here is slightly unfortunate, since we turn loops like:

    while (strbuf_getline(&buf, stdin) != EOF)

into:

    while (1) {
        int ret;
        if (opt->nul_terminated)
            ret = strbuf_getline_nul(&input, stdin);
        else
            ret = strbuf_getline(&input, stdin);

        if (ret == EOF)
            break;
    }

It's tempting to think that we could use `strbuf_getwholeline()` and
specify either `\n` or `\0` as the terminating character. But for input
on platforms that include a CR character preceeding the LF, this
wouldn't quite be the same, since `strbuf_getline(...)` will trim any
trailing CR, while `strbuf_getwholeline(&buf, stdin, '\n')` will not.

In the future, we could clean this up further by introducing a variant
of `strbuf_getwholeline()` that addresses the aforementioned gap, but
that approach felt too heavy-handed for this pair of uses.

Some tests are added in t1006 to ensure that `cat-file` produces the
same output in `--batch`, `--batch-check`, and `--batch-command` modes
with and without the new `-z` option.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-22 21:42:06 -07:00
Siddharth Asthana ec031da9f9 cat-file: add mailmap support
git-cat-file is used by tools like GitLab to get commit tag contents
that are then displayed to users. This content which has author,
committer or tagger information, could benefit from passing through the
mailmap mechanism before being sent or displayed.

This patch adds --[no-]use-mailmap command line option to the git
cat-file command. It also adds --[no-]mailmap option as an alias to
--[no-]use-mailmap.

This patch also introduces new test cases to test the mailmap mechanism in
git cat-file command.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: John Cai <johncai86@gmail.com>
Helped-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Siddharth Asthana <siddharthasthana31@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-18 12:55:53 -07:00
Ævar Arnfjörð Bjarmason 27472b5195 cat-file: fix a common "struct object_context" memory leak
Fix a memory leak where "cat-file" will leak the "path" member. See
e5fba602e5 (textconv: support for cat_file, 2010-06-15) for the code
that introduced the offending get_oid_with_context() call (called
get_sha1_with_context() at the time).

As a result we can mark several tests as passing with SANITIZE=leak
using "TEST_PASSES_SANITIZE_LEAK=true".

As noted in dc944b65f1 (get_sha1_with_context: dynamically allocate
oc->path, 2017-05-19) callers must free the "path" member. That same
commit added the relevant free() to this function, but we weren't
catching cases where we'd return early.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 11:43:43 -07:00
Ævar Arnfjörð Bjarmason d90dafbe31 cat-file: fix a memory leak in --batch-command mode
Fix a memory leak introduced in 440c705ea6 (cat-file: add
--batch-command mode, 2022-02-18). The free_cmds() function was only
called on "queued_nr" if we had a "flush" command. As the "without
flush for blob info" test added in the same commit shows we can't rely
on that, so let's call free_cmds() again at the end.

Since "nr" follows the usual pattern of being set to 0 if we've
free()'d the memory already it's OK to call it twice, even in cases
where we are doing a "flush".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 11:43:43 -07:00
Junio C Hamano 889860e1ad Merge branch 'jc/cat-file-batch-default-format-optim'
Optimize away strbuf_expand() call with a hardcoded formatting logic
specific for the default format in the --batch and --batch-check
options of "git cat-file".

* jc/cat-file-batch-default-format-optim:
  cat-file: skip expanding default format
2022-03-23 14:09:31 -07:00
Junio C Hamano 430883a70c Merge branch 'ab/object-file-api-updates'
Object-file API shuffling.

* ab/object-file-api-updates:
  object-file API: pass an enum to read_object_with_reference()
  object-file.c: add a literal version of write_object_file_prepare()
  object-file API: have hash_object_file() take "enum object_type"
  object API: rename hash_object_file_literally() to write_*()
  object-file API: split up and simplify check_object_signature()
  object API users + docs: check <0, not !0 with check_object_signature()
  object API docs: move check_object_signature() docs to cache.h
  object API: correct "buf" v.s. "map" mismatch in *.c and *.h
  object-file API: have write_object_file() take "enum object_type"
  object-file API: add a format_object_header() function
  object-file API: return "void", not "int" from hash_object_file()
  object-file.c: split up declaration of unrelated variables
2022-03-16 17:53:08 -07:00
John Cai eb54a3391b cat-file: skip expanding default format
When format is passed into --batch, --batch-check, --batch-command,
the format gets expanded. When nothing is passed in, the default format
is set and the expand_format() gets called.

We can save on these cycles by hardcoding how to print the
information when nothing is passed as the format, or when the default
format is passed. There is no need for the fully expanded format with
the default. Since batch_object_write() happens on every object provided
in batch mode, we get a nice performance improvement.

git rev-list --all > /tmp/all-obj.txt

git cat-file --batch-check </tmp/all-obj.txt

with HEAD^:

Time (mean ± σ): 57.6 ms ± 1.7 ms [User: 51.5 ms, System: 6.2 ms]
Range (min … max): 54.6 ms … 64.7 ms 50 runs

with HEAD:

Time (mean ± σ): 49.8 ms ± 1.7 ms [User: 42.6 ms, System: 7.3 ms]
Range (min … max): 46.9 ms … 55.9 ms 56 runs

If nothing is provided as a format argument, or if the default format is
passed, skip expanding of the format and print the object info with a
default format.

See https://lore.kernel.org/git/87eecf8ork.fsf@evledraar.gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: John Cai <johncai86@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-15 10:15:32 -07:00
Ævar Arnfjörð Bjarmason 6aea6baeb3 object-file API: pass an enum to read_object_with_reference()
Change the read_object_with_reference() function to take an "enum
object_type". It was not prepared to handle an arbitrary "const
char *type", as it was itself calling type_from_string().

Let's change the only caller that passes in user data to use
type_from_string(), and convert the rest to use e.g. "OBJ_TREE"
instead of "tree_type".

The "cat-file" caller is not on the codepath that
handles"--allow-unknown", so the type_from_string() there is safe. Its
use of type_from_string() doesn't functionally differ from that of the
pre-image.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-25 17:16:32 -08:00
John Cai 440c705ea6 cat-file: add --batch-command mode
Add a new flag --batch-command that accepts commands and arguments
from stdin, similar to git-update-ref --stdin.

At GitLab, we use a pair of long running cat-file processes when
accessing object content. One for iterating over object metadata with
--batch-check, and the other to grab object contents with --batch.

However, if we had --batch-command, we wouldn't need to keep both
processes around, and instead just have one --batch-command process
where we can flip between getting object info, and getting object
contents. Since we have a pair of cat-file processes per repository,
this means we can get rid of roughly half of long lived git cat-file
processes. Given there are many repositories being accessed at any given
time, this can lead to huge savings.

git cat-file --batch-command

will enter an interactive command mode whereby the user can enter in
commands and their arguments that get queued in memory:

<command1> [arg1] [arg2] LF
<command2> [arg1] [arg2] LF

When --buffer mode is used, commands will be queued in memory until a
flush command is issued that execute them:

flush LF

The reason for a flush command is that when a consumer process (A)
talks to a git cat-file process (B) and interactively writes to and
reads from it in --buffer mode, (A) needs to be able to control when
the buffer is flushed to stdout.

Currently, from (A)'s perspective, the only way is to either

1. kill (B)'s process
2. send an invalid object to stdin.

1. is not ideal from a performance perspective as it will require
spawning a new cat-file process each time, and 2. is hacky and not a
good long term solution.

With this mechanism of queueing up commands and letting (A) issue a
flush command, process (A) can control when the buffer is flushed and
can guarantee it will receive all of the output when in --buffer mode.
--batch-command also will not allow (B) to flush to stdout until a flush
is received.

This patch adds the basic structure for adding command which can be
extended in the future to add more commands. It also adds the following
two commands (on top of the flush command):

contents <object> LF
info <object> LF

The contents command takes an <object> argument and prints out the object
contents.

The info command takes an <object> argument and prints out the object
metadata.

These can be used in the following way with --buffer:

info <object> LF
contents <object> LF
contents <object> LF
info <object> LF
flush LF
info <object> LF
flush LF

When used without --buffer:

info <object> LF
contents <object> LF
contents <object> LF
info <object> LF
info <object> LF

Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: John Cai <johncai86@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-18 11:21:46 -08:00
John Cai ac4e58cab9 cat-file: introduce batch_mode enum to replace print_contents
A future patch introduces a new --batch-command flag. Including --batch
and --batch-check, we will have a total of three batch modes. print_contents
is the only boolean on the batch_options sturct used to distinguish
between the different modes. This makes the code harder to read.

To reduce potential confusion, replace print_contents with an enum to
help readability and clarity.

Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: John Cai <johncai86@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-18 11:21:46 -08:00
John Cai a2c75526d2 cat-file: rename cmdmode to transform_mode
In the next patch, we will add an enum on the batch_options struct that
indicates which type of batch operation will be used: --batch,
--batch-check and the soon to be  --batch-command that will read
commands from stdin. --batch-command mode might get confused with
the cmdmode flag.

There is value in renaming cmdmode in any case. cmdmode refers to how
the result output of the blob will be transformed, either according to
--filter or --textconv. So transform_mode is a more descriptive name
for the flag.

Rename cmdmode to transform_mode in cat-file.c

Signed-off-by: John Cai <johncai86@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-18 11:21:46 -08:00
Ævar Arnfjörð Bjarmason 5fb249021c cat-file: s/_/-/ in typo'd usage_msg_optf() message
Fix a typo in my recent 03dc51fe849 (cat-file: fix remaining usage
bugs, 2021-10-09).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Acked-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-01-12 10:12:39 -08:00
Ævar Arnfjörð Bjarmason 83dc443439 cat-file: don't whitespace-pad "(...)" in SYNOPSIS and usage output
Fix up whitespace issues around "(... | ...)" in the SYNOPSIS and
usage. These were introduced in ab/cat-file series. See
e145efa605 (Merge branch 'ab/cat-file' into next, 2022-01-05). In
particular 57d6a1cf96, 5a40417876 and 97fe725075 in that series.

We'll now correctly emit this usage output:

    $ git cat-file -h
    usage: git cat-file <type> <object>
       or: git cat-file (-e | -p) <object>
       or: git cat-file (-t | -s) [--allow-unknown-type] <object>
    [...]

Before this the last line of that would be inconsistent with the
preceding "(-e | -p)":

   or: git cat-file ( -t | -s ) [--allow-unknown-type] <object>

Reported-by: Jiang Xin <worldhello.net@gmail.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Acked-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-01-12 10:12:20 -08:00
Jean-Noël Avila 246cac8505 i18n: turn even more messages into "cannot be used together" ones
Even if some of these messages are not subject to gettext i18n, this
helps bring a single style of message for a given error type.

Signed-off-by: Jean-Noël Avila <jn.avila@free.fr>
Reviewed-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-01-05 13:31:00 -08:00
Ævar Arnfjörð Bjarmason 245b948815 cat-file: use GET_OID_ONLY_TO_DIE in --(textconv|filters)
Change the cat_one_file() logic that calls get_oid_with_context()
under --textconv and --filters to use the GET_OID_ONLY_TO_DIE flag,
thus improving the error messaging emitted when e.g. <path> is missing
but <rev> is not.

To service the "cat-file" use-case we need to introduce a new
"GET_OID_REQUIRE_PATH" flag, otherwise it would exit early as soon as
a valid "HEAD" was resolved, but in the "cat-file" case being changed
we always need a valid revision and path.

This arguably makes the "<bad rev>:<bad path>" and "<bad
rev>:<good (in HEAD) path>" use cases worse, as we won't quote the
<path> component at the user anymore, but let's just use the existing
logic "git log" et al use for now. We can improve the messaging for
those cases as a follow-up for all callers.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-30 13:05:29 -08:00
Ævar Arnfjörð Bjarmason 57d6a1cf96 cat-file: correct and improve usage information
Change the usage output emitted on "git cat-file -h" to group related
options, making it clear to users which options go with which other
ones.

The new output is:

    Check object existence or emit object contents
        -e                    check if <object> exists
        -p                    pretty-print <object> content

    Emit [broken] object attributes
        -t                    show object type (one of 'blob', 'tree', 'commit', 'tag', ...)
        -s                    show object size
        --allow-unknown-type  allow -s and -t to work with broken/corrupt objects

    Batch objects requested on stdin (or --batch-all-objects)
        --batch[=<format>]    show full <object> or <rev> contents
        --batch-check[=<format>]
                              like --batch, but don't emit <contents>
        --batch-all-objects   with --batch[-check]: ignores stdin, batches all known objects

    Change or optimize batch output
        --buffer              buffer --batch output
        --follow-symlinks     follow in-tree symlinks
        --unordered           do not order objects before emitting them

    Emit object (blob or tree) with conversion or filter (stand-alone, or with batch)
        --textconv            run textconv on object's content
        --filters             run filters on object's content
        --path blob|tree      use a <path> for (--textconv | --filters ); Not with 'batch'

The old usage was:

    <type> can be one of: blob, tree, commit, tag
        -t                    show object type
        -s                    show object size
        -e                    exit with zero when there's no error
        -p                    pretty-print object's content
        --textconv            for blob objects, run textconv on object's content
        --filters             for blob objects, run filters on object's content
        --batch-all-objects   show all objects with --batch or --batch-check
        --path <blob>         use a specific path for --textconv/--filters
        --allow-unknown-type  allow -s and -t to work with broken/corrupt objects
        --buffer              buffer --batch output
        --batch[=<format>]    show info and content of objects fed from the standard input
        --batch-check[=<format>]
                              show info about objects fed from the standard input
        --follow-symlinks     follow in-tree symlinks (used with --batch or --batch-check)
        --unordered           do not order --batch-all-objects output

While shorter, I think the new one is easier to understand, as
e.g. "--allow-unknown-type" is grouped with "-t" and "-s", as it can
only be combined with those options. The same goes for "--buffer",
"--unordered" etc.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-30 13:05:29 -08:00
Ævar Arnfjörð Bjarmason b3fe468075 cat-file: fix remaining usage bugs
With the migration of --batch-all-objects to OPT_CMDMODE() in the
preceding commit one bug with combining it and other OPT_CMDMODE()
options was solved, but we were still left with e.g. --buffer silently
being discarded when not in batch mode.

Fix all those bugs, and in addition emit errors telling the user
specifically what options can't be combined with what other options,
before this we'd usually just emit the cryptic usage text and leave
the users to work it out by themselves.

This change is rather large, because to do so we need to untangle the
options processing so that we can not only error out, but emit
sensible errors, and e.g. emit errors about options before errors
about stray argc elements (as they might become valid if the option
were removed).

Some of the output changes ("error:" to "fatal:" with
usage_msg_opt[f]()), but none of the exit codes change, except in
those cases where we silently accepted bad option combinations before,
now we'll error out.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-30 13:05:29 -08:00
Ævar Arnfjörð Bjarmason 485fd2c3da cat-file: make --batch-all-objects a CMDMODE
The usage of OPT_CMDMODE() in "cat-file"[1] was added in parallel with
the development of[3] the --batch-all-objects option[4], so we've
since grown[5] checks that it can't be combined with other command
modes, when it should just be made a top-level command-mode
instead. It doesn't combine with --filters, --textconv etc.

By giving parse_options() information about what options are mutually
exclusive with one another we can get the die() message being removed
here for free, we didn't even use that removed message in some cases,
e.g. for both of:

    --batch-all-objects --textconv
    --batch-all-objects --filters

We'd take the "goto usage" in the "if (opt)" branch, and never reach
the previous message. Now we'll emit e.g.:

    $ git cat-file --batch-all-objects --filters
    error: option `filters' is incompatible with --batch-all-objects

1. b48158ac94 (cat-file: make the options mutually exclusive, 2015-05-03)
2. https://lore.kernel.org/git/xmqqtwspgusf.fsf@gitster.dls.corp.google.com/
3. https://lore.kernel.org/git/20150622104559.GG14475@peff.net/
4. 6a951937ae (cat-file: add --batch-all-objects option, 2015-06-22)
5. 321459439e (cat-file: support --textconv/--filters in batch mode, 2016-09-09)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-30 13:05:29 -08:00
Ævar Arnfjörð Bjarmason 5a40417876 cat-file: move "usage" variable to cmd_cat_file()
There's no benefit to defining this at a distance, and it makes the
code harder to read as you've got to scroll up to see the usage that
corresponds to the options.

In subsequent commits I'll make use of usage_msg_opt(), which will be
quite noisy if I have to use the long "cat_file_usage" variable,
there's no other command being defined in this file, so let's rename
it to just "usage".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-30 13:05:29 -08:00
Ævar Arnfjörð Bjarmason 97fe725075 cat-file docs: fix SYNOPSIS and "-h" output
There were various inaccuracies in the previous SYNOPSIS output,
e.g. "--path" is not something that can optionally go with any options
except --textconv or --filters, as the output implied.

The opening line of the DESCRIPTION section is also "In its first
form[...]", which refers to "git cat-file <type> <object>", but the
SYNOPSIS section wasn't showing that as the first form!

That part of the documentation made sense in
d83a42f34a (Documentation: minor grammatical fixes in
git-cat-file.txt, 2009-03-22) when it was introduced, but since then
various options that were added have made that intro make no sense in
the context it was in. Now the two will match again.

The usage output here is not properly aligned on "master" currently,
but will be with my in-flight 4631cfc20b (parse-options: properly
align continued usage output, 2021-09-21), so let's indent things
correctly in the C code in anticipation of that.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-30 13:05:28 -08:00
Jeff King bf972896d7 cat-file: use packed_object_info() for --batch-all-objects
When "cat-file --batch-all-objects" iterates over each object, it knows
where to find each one. But when we look up details of the object, we
don't use that information at all.

This patch teaches it to use the pack/offset pair when we're iterating
over objects in a pack. This yields a measurable speed improvement
(timings on a fully packed clone of linux.git):

  Benchmark #1: ./git.old cat-file --batch-all-objects --unordered --batch-check="%(objecttype) %(objectname)"
    Time (mean ± σ):      8.128 s ±  0.118 s    [User: 7.968 s, System: 0.156 s]
    Range (min … max):    8.007 s …  8.301 s    10 runs

  Benchmark #2: ./git.new cat-file --batch-all-objects --unordered --batch-check="%(objecttype) %(objectname)"
    Time (mean ± σ):      4.294 s ±  0.064 s    [User: 4.167 s, System: 0.125 s]
    Range (min … max):    4.227 s …  4.457 s    10 runs

  Summary
    './git.new cat-file --batch-all-objects --unordered --batch-check="%(objecttype) %(objectname)"' ran
      1.89 ± 0.04 times faster than './git.old cat-file --batch-all-objects --unordered --batch-check="%(objecttype) %(objectname)"

The implementation is pretty simple: we just call packed_object_info()
instead of oid_object_info_extended() when we can. Most of the changes
are just plumbing the pack/offset pair through the callstack. There is
one subtlety: replace lookups are not handled by packed_object_info().
But since those are disabled for --batch-all-objects, and since we'll
only have pack info when that option is in effect, we don't have to
worry about that.

There are a few limitations to this optimization which we could address
with further work:

 - I didn't bother recording when we found an object loose. Technically
   this could save us doing a fruitless lookup in the pack index. But
   opening and mmap-ing a loose object is so expensive in the first
   place that this doesn't matter much. And if your repository is large
   enough to care about per-object performance, most objects are going
   to be packed anyway.

 - This works only in --unordered mode. For the sorted mode, we'd have
   to record the pack/offset pair as part of our oid-collection. That's
   more code, plus at least 16 extra bytes of heap per object. It would
   probably still be a net win in runtime, but we'd need to measure.

 - For --batch, this still helps us with getting the object metadata,
   but we still do a from-scratch lookup for the object contents. This
   probably doesn't matter that much, because the lookup cost will be
   much smaller relative to the cost of actually unpacking and printing
   the objects.

   For small objects, we could probably swap out read_object_file() for
   using packed_object_info() with a "object_info.contentp" to get the
   contents. But we'd still need to deal with streaming for larger
   objects. A better path forward here is to teach the initial
   oid_object_info_extended() / packed_object_info() calls to retrieve
   the contents of smaller objects while they are already being
   accessed. That would save the extra lookup entirely. But it's a
   non-trivial feature to add to the object_info code, so I left it for
   now.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 15:45:14 -07:00
Jeff King 818e393084 cat-file: split ordered/unordered batch-all-objects callbacks
When we originally added --batch-all-objects, it stuffed everything into
an oid_array(), and then iterated over that array with a callback to
write the actual output.

When we later added --unordered, that code path writes immediately as we
discover each object, but just calls the same batch_object_cb() as our
entry point to the writing code. That callback has a narrow interface;
it only receives the oid, but we know much more about each object in the
unordered write (which we'll make use of in the next patch). So let's
just call batch_object_write() directly. The callback wasn't saving us
much effort.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 15:45:14 -07:00
Jeff King 5c5b29b459 cat-file: disable refs/replace with --batch-all-objects
When we're enumerating all objects in the object database, it doesn't
make sense to respect refs/replace. The point of this option is to
enumerate all of the objects in the database at a low level. By
definition we'd already show the replacement object's contents (under
its real oid), and showing those contents under another oid is almost
certainly working against what the user is trying to do.

Note that you could make the same argument for something like:

  git show-index <foo.idx |
  awk '{print $2}' |
  git cat-file --batch

but there we can't know in cat-file exactly what the user intended,
because we don't know the source of the input. They could be trying to
do low-level debugging, or they could be doing something more high-level
(e.g., imagine a porcelain built around cat-file for its object
accesses). So in those cases, we'll have to rely on the user specifying
"git --no-replace-objects" to tell us what to do.

One _could_ make an argument that "cat-file --batch" is sufficiently
low-level plumbing that it should not respect replace-objects at all
(and the caller should do any replacement if they want it).  But we have
been doing so for some time. The history is a little tangled:

  - looking back as far as v1.6.6, we would not respect replace refs for
    --batch-check, but would for --batch (because the former used
    sha1_object_info(), and the replace mechanism only affected actual
    object reads)

  - this discrepancy was made even weirder by 98e2092b50 (cat-file:
    teach --batch to stream blob objects, 2013-07-10), where we always
    output the header using the --batch-check code, and then printed the
    object separately. This could lead to "cat-file --batch" dying (when
    it notices the size or type changed for a non-blob object) or even
    producing bogus output (in streaming mode, we didn't notice that we
    wrote the wrong number of bytes).

  - that persisted until 1f7117ef7a (sha1_file: perform object
    replacement in sha1_object_info_extended(), 2013-12-11), which then
    respected replace refs for both forms.

So it has worked reliably this way for over 7 years, and we should make
sure it continues to do so. That could also be an argument that
--batch-all-objects should not change behavior (which this patch is
doing), but I really consider the current behavior to be an unintended
bug. It's a side effect of how the code is implemented (feeding the oids
back into oid_object_info() rather than looking at what we found while
reading the loose and packed object storage).

The implementation is straight-forward: we just disable the global
read_replace_refs flag when we're in --batch-all-objects mode. It would
perhaps be a little cleaner to change the flag we pass to
oid_object_info_extended(), but that's not enough. We also read objects
via read_object_file() and stream_blob_to_fd(). The former could switch
to its _extended() form, but the streaming code has no mechanism for
disabling replace refs. Setting the global flag works, and as a bonus,
it's impossible to have any "oops, we're sometimes replacing the object
and sometimes not" bugs in the output (like the ones caused by
98e2092b50 above).

The tests here cover the regular-input and --batch-all-objects cases,
for both --batch-check and --batch. There is a test in t6050 that covers
the regular-input case with --batch already, but this new one goes much
further in actually verifying the output (plus covering --batch-check
explicitly). This is perhaps a little overkill and the tests would be
simpler just covering --batch-check, but I wanted to make sure we're
checking that --batch output is consistent between the header and the
content. The global-flag technique used here makes that easy to get
right, but this is future-proofing us against regressions.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 15:45:14 -07:00