Commit Graph

60 Commits

Author SHA1 Message Date
Jeff King
61cc4be7ec t1006: stop using 0-padded timestamps
The fake objects in t1006 use dummy timestamps like "0000000000 +0000".
While this does make them look more like normal timestamps (which,
unless it is 1970, have many digits), it actually violates our fsck
checks, which complain about zero-padded timestamps.

This doesn't currently break anything, but let's future-proof our tests
against a version of hash-object which is a little more careful about
its input. We don't actually care about the exact values here (and in
fact, the helper functions in this script end up removing the timestamps
anyway, so we don't even have to adjust other parts of the tests).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-18 12:59:44 -08:00
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
Taylor Blau
3639fefe7d t1006: extract --batch-command inputs to variables
A future commit will want to ensure that various `--batch`-related
options produce the same output whether their input is newline
terminated, or NUL terminated (and a to-be-implemented `-z` option
exists).

To prepare for this, extract the given input(s) into separate variables
to that their LF characters can easily be converted into NUL bytes when
testing the new `-z` mode.

This is consistent with other tests in t1006 (which these days is no
longer a shining example of our CodingGuidelines).

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-22 21:42:05 -07:00
Ævar Arnfjörð Bjarmason
4627c67fa6 object-file: fix a unpack_loose_header() regression in 3b6a8db3b0
Fix a regression in my 3b6a8db3b0 (object-file.c: use "enum" return
type for unpack_loose_header(), 2021-10-01) revealed both by running
the test suite with --valgrind, and with the amended "git fsck" test.

In practice this regression in v2.34.0 caused us to claim that we
couldn't parse the header, as opposed to not being able to unpack
it. Before the change in the C code the test_cmp added here would emit:

	-error: unable to unpack header of ./objects/e6/9de29bb2d1d6434b8b29ae775ad8c2e48c5391
	+error: unable to parse header of ./objects/e6/9de29bb2d1d6434b8b29ae775ad8c2e48c5391

I.e. we'd proceed to call parse_loose_header() on the uninitialized
"hdr" value, and it would have been very unlikely for that
uninitialized memory to be a valid git object.

The other callers of unpack_loose_header() were already checking the
enum values exhaustively. See 3b6a8db3b0 and
5848fb11ac (object-file.c: return ULHR_TOO_LONG on "header too long",
2021-10-01).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-12 15:42:26 -07:00
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
4cf5d53b62 cat-file: add remove_timestamp helper
maybe_remove_timestamp() takes arguments, but it would be useful to have
a function that reads from stdin and strips the timestamp. This would
allow tests to pipe data into a function to remove timestamps, and
wouldn't have to always assign a variable. This is especially helpful
when the data is multiple lines.

Keep maybe_remove_timestamp() the same, but add a remove_timestamp
helper that reads from stdin.

The tests in the next patch will make use of this.

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
Junio C Hamano
008028a910 Merge branch 'ab/cat-file'
Assorted updates to "git cat-file", especially "-h".

* ab/cat-file:
  cat-file: s/_/-/ in typo'd usage_msg_optf() message
  cat-file: don't whitespace-pad "(...)" in SYNOPSIS and usage output
  cat-file: use GET_OID_ONLY_TO_DIE in --(textconv|filters)
  object-name.c: don't have GET_OID_ONLY_TO_DIE imply *_QUIETLY
  cat-file: correct and improve usage information
  cat-file: fix remaining usage bugs
  cat-file: make --batch-all-objects a CMDMODE
  cat-file: move "usage" variable to cmd_cat_file()
  cat-file docs: fix SYNOPSIS and "-h" output
  parse-options API: add a usage_msg_optf()
  cat-file tests: test messaging on bad objects/paths
  cat-file tests: test bad usage
2022-02-05 09:42:31 -08:00
Junio C Hamano
4f4b18497a Merge branch 'es/test-chain-lint'
Broken &&-chains in the test scripts have been corrected.

* es/test-chain-lint:
  t6000-t9999: detect and signal failure within loop
  t5000-t5999: detect and signal failure within loop
  t4000-t4999: detect and signal failure within loop
  t0000-t3999: detect and signal failure within loop
  tests: simplify by dropping unnecessary `for` loops
  tests: apply modern idiom for exiting loop upon failure
  tests: apply modern idiom for signaling test failure
  tests: fix broken &&-chains in `{...}` groups
  tests: fix broken &&-chains in `$(...)` command substitutions
  tests: fix broken &&-chains in compound statements
  tests: use test_write_lines() to generate line-oriented output
  tests: simplify construction of large blocks of text
  t9107: use shell parameter expansion to avoid breaking &&-chain
  t6300: make `%(raw:size) --shell` test more robust
  t5516: drop unnecessary subshell and command invocation
  t4202: clarify intent by creating expected content less cleverly
  t1020: avoid aborting entire test script when one test fails
  t1010: fix unnoticed failure on Windows
  t/lib-pager: use sane_unset() to avoid breaking &&-chain
2022-01-03 16:24:15 -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
ddf8420b59 cat-file tests: test bad usage
Stress test the usage emitted when options are combined in ways that
isn't supported. Let's test various option combinations, some of these
we buggily allow right now.

E.g. this reveals a bug in 321459439e (cat-file: support
--textconv/--filters in batch mode, 2016-09-09) that we'll fix in a
subsequent commit. We're supposed to be emitting a relevant message
when --batch-all-objects is combined with --textconv or --filters, but
we don't.

The cases of needing to assign to opt=2 in the "opt" loop are because
on those we do the right thing already, in subsequent commits the
"test_expect_failure" cases will be fixed, and the for-loops unified.

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
Eric Sunshine
7abcbcb7ea tests: fix broken &&-chains in {...} groups
The top-level &&-chain checker built into t/test-lib.sh causes tests to
magically exit with code 117 if the &&-chain is broken. However, it has
the shortcoming that the magic does not work within `{...}` groups,
`(...)` subshells, `$(...)` substitutions, or within bodies of compound
statements, such as `if`, `for`, `while`, `case`, etc. `chainlint.sed`
partly fills in the gap by catching broken &&-chains in `(...)`
subshells, but bugs can still lurk behind broken &&-chains in the other
cases.

Fix broken &&-chains in `{...}` groups in order to reduce the number of
possible lurking bugs.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-13 10:29:48 -08:00
Eric Sunshine
c576868eaf tests: fix broken &&-chains in $(...) command substitutions
The top-level &&-chain checker built into t/test-lib.sh causes tests to
magically exit with code 117 if the &&-chain is broken. However, it has
the shortcoming that the magic does not work within `{...}` groups,
`(...)` subshells, `$(...)` substitutions, or within bodies of compound
statements, such as `if`, `for`, `while`, `case`, etc. `chainlint.sed`
partly fills in the gap by catching broken &&-chains in `(...)`
subshells, but bugs can still lurk behind broken &&-chains in the other
cases.

Fix broken &&-chains in `$(...)` command substitutions in order to
reduce the number of possible lurking bugs.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-13 10:29:48 -08:00
Han-Wen Nienhuys
e9706a188f refs: introduce REF_SKIP_OID_VERIFICATION flag
This lets the ref-store test helper write non-existent or unparsable objects
into the ref storage.

Use this to make t1006 and t3800 independent of the files storage backend.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-07 13:15:19 -08:00
Junio C Hamano
061a21d36d Merge branch 'ab/fsck-unexpected-type'
"git fsck" has been taught to report mismatch between expected and
actual types of an object better.

* ab/fsck-unexpected-type:
  fsck: report invalid object type-path combinations
  fsck: don't hard die on invalid object types
  object-file.c: stop dying in parse_loose_header()
  object-file.c: return ULHR_TOO_LONG on "header too long"
  object-file.c: use "enum" return type for unpack_loose_header()
  object-file.c: simplify unpack_loose_short_header()
  object-file.c: make parse_loose_header_extended() public
  object-file.c: return -1, not "status" from unpack_loose_header()
  object-file.c: don't set "typep" when returning non-zero
  cat-file tests: test for current --allow-unknown-type behavior
  cat-file tests: add corrupt loose object test
  cat-file tests: test for missing/bogus object with -t, -s and -p
  cat-file tests: move bogus_* variable declarations earlier
  fsck tests: test for garbage appended to a loose object
  fsck tests: test current hash/type mismatch behavior
  fsck tests: refactor one test to use a sub-repo
  fsck tests: add test for fsck-ing an unknown type
2021-10-25 16:06:56 -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
Jeff King
e879295b20 t1006: clean up broken objects
A few of the tests create intentionally broken objects with broken
types. Let's clean them up after we're done with them, so that later
tests don't get confused (we hadn't noticed because this only affects
tests which use --batch-all-objects, but I'm about to add more).

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
Ævar Arnfjörð Bjarmason
96e41f58fe fsck: report invalid object type-path combinations
Improve the error that's emitted in cases where we find a loose object
we parse, but which isn't at the location we expect it to be.

Before this change we'd prefix the error with a not-a-OID derived from
the path at which the object was found, due to an emergent behavior in
how we'd end up with an "OID" in these codepaths.

Now we'll instead say what object we hashed, and what path it was
found at. Before this patch series e.g.:

    $ git hash-object --stdin -w -t blob </dev/null
    e69de29bb2
    $ mv objects/e6/ objects/e7

Would emit ("[...]" used to abbreviate the OIDs):

    git fsck
    error: hash mismatch for ./objects/e7/9d[...] (expected e79d[...])
    error: e79d[...]: object corrupt or missing: ./objects/e7/9d[...]

Now we'll instead emit:

    error: e69d[...]: hash-path mismatch, found at: ./objects/e7/9d[...]

Furthermore, we'll do the right thing when the object type and its
location are bad. I.e. this case:

    $ git hash-object --stdin -w -t garbage --literally </dev/null
    8315a83d2acc4c174aed59430f9a9c4ed926440f
    $ mv objects/83 objects/84

As noted in an earlier commits we'd simply die early in those cases,
until preceding commits fixed the hard die on invalid object type:

    $ git fsck
    fatal: invalid object type

Now we'll instead emit sensible error messages:

    $ git fsck
    error: 8315[...]: hash-path mismatch, found at: ./objects/84/15[...]
    error: 8315[...]: object is of unknown type 'garbage': ./objects/84/15[...]

In both fsck.c and object-file.c we're using null_oid as a sentinel
value for checking whether we got far enough to be certain that the
issue was indeed this OID mismatch.

We need to add the "object corrupt or missing" special-case to deal
with cases where read_loose_object() will return an error before
completing check_object_signature(), e.g. if we have an error in
unpack_loose_rest() because we find garbage after the valid gzip
content:

    $ git hash-object --stdin -w -t blob </dev/null
    e69de29bb2
    $ chmod 755 objects/e6/9de29bb2d1d6434b8b29ae775ad8c2e48c5391
    $ echo garbage >>objects/e6/9de29bb2d1d6434b8b29ae775ad8c2e48c5391
    $ git fsck
    error: garbage at end of loose object 'e69d[...]'
    error: unable to unpack contents of ./objects/e6/9d[...]
    error: e69d[...]: object corrupt or missing: ./objects/e6/9d[...]

There is currently some weird messaging in the edge case when the two
are combined, i.e. because we're not explicitly passing along an error
state about this specific scenario from check_stream_oid() via
read_loose_object() we'll end up printing the null OID if an object is
of an unknown type *and* it can't be unpacked by zlib, e.g.:

    $ git hash-object --stdin -w -t garbage --literally </dev/null
    8315a83d2acc4c174aed59430f9a9c4ed926440f
    $ chmod 755 objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f
    $ echo garbage >>objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f
    $ /usr/bin/git fsck
    fatal: invalid object type
    $ ~/g/git/git fsck
    error: garbage at end of loose object '8315a83d2acc4c174aed59430f9a9c4ed926440f'
    error: unable to unpack contents of ./objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f
    error: 8315a83d2acc4c174aed59430f9a9c4ed926440f: object corrupt or missing: ./objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f
    error: 0000000000000000000000000000000000000000: object is of unknown type 'garbage': ./objects/83/15a83d2acc4c174aed59430f9a9c4ed926440f
    [...]

I think it's OK to leave that for future improvements, which would
involve enum-ifying more error state as we've done with "enum
unpack_loose_header_result" in preceding commits. In these
increasingly more obscure cases the worst that can happen is that
we'll get slightly nonsensical or inapplicable error messages.

There's other such potential edge cases, all of which might produce
some confusing messaging, but still be handled correctly as far as
passing along errors goes. E.g. if check_object_signature() returns
and oideq(real_oid, null_oid()) is true, which could happen if it
returns -1 due to the read_istream() call having failed.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-01 15:06:01 -07:00
Ævar Arnfjörð Bjarmason
5848fb11ac object-file.c: return ULHR_TOO_LONG on "header too long"
Split up the return code for "header too long" from the generic
negative return value unpack_loose_header() returns, and report via
error() if we exceed MAX_HEADER_LEN.

As a test added earlier in this series in t1006-cat-file.sh shows
we'll correctly emit zlib errors from zlib.c already in this case, so
we have no need to carry those return codes further down the
stack. Let's instead just return ULHR_TOO_LONG saying we ran into the
MAX_HEADER_LEN limit, or other negative values for "unable to unpack
<OID> header".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-01 15:06:00 -07:00
Ævar Arnfjörð Bjarmason
dd45a56246 cat-file tests: test for current --allow-unknown-type behavior
Add more tests for the current --allow-unknown-type behavior. As noted
in [1] I don't think much of this makes sense, but let's test for it
as-is so we can see if the behavior changes in the future.

1. https://lore.kernel.org/git/87r1i4qf4h.fsf@evledraar.gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-01 15:06:00 -07:00
Ævar Arnfjörð Bjarmason
7e7d220d9d cat-file tests: add corrupt loose object test
Fix a blindspot in the tests for "cat-file" (and by proxy, the guts of
object-file.c) by testing that when we can't decode a loose object
with zlib we'll emit an error from zlib.c.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-01 15:05:59 -07:00
Ævar Arnfjörð Bjarmason
59b8283d55 cat-file tests: test for missing/bogus object with -t, -s and -p
When we look up a missing object with cat_one_file() what error we
print out currently depends on whether we'll error out early in
get_oid_with_context(), or if we'll get an error later from
oid_object_info_extended().

The --allow-unknown-type flag then changes whether we pass the
"OBJECT_INFO_ALLOW_UNKNOWN_TYPE" flag to get_oid_with_context() or
not.

The "-p" flag is yet another special-case in printing the same output
on the deadbeef OID as we'd emit on the deadbeef_short OID for the
"-s" and "-t" options, it also doesn't support the
"--allow-unknown-type" flag at all.

Let's test the combination of the two sets of [-t, -s, -p] and
[--{no-}allow-unknown-type] (the --no-allow-unknown-type is implicit
in not supplying it), as well as a [missing,bogus] object pair.

This extends tests added in 3e370f9faf (t1006: add tests for git
cat-file --allow-unknown-type, 2015-05-03).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-01 15:05:59 -07:00
Ævar Arnfjörð Bjarmason
70e4a57762 cat-file tests: move bogus_* variable declarations earlier
Change the short/long bogus bogus object type variables into a form
where the two sets can be used concurrently. This'll be used by
subsequently added tests.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-01 15:05:59 -07:00
Junio C Hamano
5d96bcbc06 Merge branch 'zh/cat-file-batch-fix'
"git cat-file --batch-all-objects"" misbehaved when "--batch" is in
use and did not ask for certain object traits.

* zh/cat-file-batch-fix:
  cat-file: merge two block into one
  cat-file: handle trivial --batch format with --batch-all-objects
2021-07-13 16:52:49 -07:00
ZheNing Hu
e16acc80a7 cat-file: handle trivial --batch format with --batch-all-objects
The --batch code to print an object assumes we found out the type of
the object from calling oid_object_info_extended(). This is true for
the default format, but even in a custom format, we manually modify
the object_info struct to ask for the type.

This assumption was broken by 845de33a5b (cat-file: avoid noop calls
to sha1_object_info_extended, 2016-05-18). That commit skips the call
to oid_object_info_extended() entirely when --batch-all-objects is in
use, and the custom format does not include any placeholders that
require calling it.

Or when the custom format only include placeholders like %(objectname) or
%(rest), oid_object_info_extended() will not get the type of the object.

This results in an error when we try to confirm that the type didn't
change:

$ git cat-file --batch=batman --batch-all-objects
batman
fatal: object 000023961a changed type!?

and also has other subtle effects (e.g., we'd fail to stream a blob,
since we don't realize it's a blob in the first place).

We can fix this by flipping the order of the setup. The check for "do
we need to get the object info" must come _after_ we've decided
whether we need to look up the type.

Helped-by: Jeff King <peff@peff.net>
Signed-off-by: ZheNing Hu <adlternative@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-06-04 07:50:26 +09:00
Ævar Arnfjörð Bjarmason
acf9de4c94 mktag: use fsck instead of custom verify_tag()
Change the validation logic in "mktag" to use fsck's fsck_tag()
instead of its own custom parser. Curiously the logic for both dates
back to the same commit[1]. Let's unify them so we're not maintaining
two sets functions to verify that a tag is OK.

The behavior of fsck_tag() and the old "mktag" code being removed here
is different in few aspects.

I think it makes sense to remove some of those checks, namely:

 A. fsck only cares that the timezone matches [-+][0-9]{4}. The mktag
    code disallowed values larger than 1400.

    Yes there's currently no timezone with a greater offset[2], but
    since we allow any number of non-offical timezones (e.g. +1234)
    passing this through seems fine. Git also won't break in the
    future if e.g. French Polynesia decides it needs to outdo the Line
    Islands when it comes to timezone extravagance.

 B. fsck allows missing author names such as "tagger <email>", mktag
    wouldn't, but would allow e.g. "tagger [2 spaces] <email>" (but
    not "tagger [1 space] <email>"). Now we allow all of these.

 C. Like B, but "mktag" disallowed spaces in the <email> part, fsck
    allows it.

In some ways fsck_tag() is stricter than "mktag" was, namely:

 D. fsck disallows zero-padded dates, but mktag didn't care. So
    e.g. the timestamp "0000000000 +0000" produces an error now. A
    test in "t1006-cat-file.sh" relied on this, it's been changed to
    use "hash-object" (without fsck) instead.

There was one check I deemed worth keeping by porting it over to
fsck_tag():

 E. "mktag" did not allow any custom headers, and by extension (as an
    empty commit is allowed) also forbade an extra stray trailing
    newline after the headers it knew about.

    Add a new check in the "ignore" category to fsck and use it. This
    somewhat abuses the facility added in efaba7cc77 (fsck:
    optionally ignore specific fsck issues completely, 2015-06-22).

    This is somewhat of hack, but probably the least invasive change
    we can make here. The fsck command will shuffle these categories
    around, e.g. under --strict the "info" becomes a "warn" and "warn"
    becomes "error". Existing users of fsck's (and others,
    e.g. index-pack) --strict option rely on this.

    So we need to put something into a category that'll be ignored by
    all existing users of the API. Pretending that
    fsck.extraHeaderEntry=error ("ignore" by default) was set serves
    to do this for us.

1. ec4465adb3 (Add "tag" objects that can be used to sign other
   objects., 2005-04-25)

2. https://en.wikipedia.org/wiki/List_of_UTC_time_offsets

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-01-05 14:58:29 -08:00
brian m. carlson
e023ff0691 t: remove test_oid_init in tests
Now that we call test_oid_init in the setup for all test scripts,
there's no point in calling it individually.  Remove all of the places
where we've done so to help keep tests tidy.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Reviewed-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-30 09:16:49 -07:00
Junio C Hamano
f2e2136ad7 Merge branch 'md/test-cleanup'
Various test scripts have been updated for style and also correct
handling of exit status of various commands.

* md/test-cleanup:
  tests: order arguments to git-rev-list properly
  t9109: don't swallow Git errors upstream of pipes
  tests: don't swallow Git errors upstream of pipes
  t/*: fix ordering of expected/observed arguments
  tests: standardize pipe placement
  Documentation: add shell guidelines
  t/README: reformat Do, Don't, Keep in mind lists
2018-10-16 16:16:01 +09:00
Matthew DeVore
bdbc17e86a tests: standardize pipe placement
Instead of using a line-continuation and pipe on the second line, take
advantage of the shell's implicit line continuation after a pipe
character.  So for example, instead of

	some long line \
		| next line

use

	some long line |
	next line

And add a blank line before and after the pipe where it aids readability
(it usually does).

This better matches the coding style documented in
Documentation/CodingGuidelines and used in shell scripts elsewhere in
the tree.

Signed-off-by: Matthew DeVore <matvore@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-07 08:51:18 +09:00
brian m. carlson
e95f53137d t1006: make hash size independent
Compute the size of the tree and commit objects we're creating by
checking for the size of an object ID and computing the resulting sizes
accordingly.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-09-17 08:10:32 -07:00
Jeff King
0750bb5b51 cat-file: support "unordered" output for --batch-all-objects
If you're going to access the contents of every object in a
packfile, it's generally much more efficient to do so in
pack order, rather than in hash order. That increases the
locality of access within the packfile, which in turn is
friendlier to the delta base cache, since the packfile puts
related deltas next to each other. By contrast, hash order
is effectively random, since the sha1 has no discernible
relationship to the content.

This patch introduces an "--unordered" option to cat-file
which iterates over packs in pack-order under the hood. You
can see the results when dumping all of the file content:

  $ time ./git cat-file --batch-all-objects --buffer --batch | wc -c
  6883195596

  real	0m44.491s
  user	0m42.902s
  sys	0m5.230s

  $ time ./git cat-file --unordered \
                        --batch-all-objects --buffer --batch | wc -c
  6883195596

  real	0m6.075s
  user	0m4.774s
  sys	0m3.548s

Same output, different order, way faster. The same speed-up
applies even if you end up accessing the object content in a
different process, like:

  git cat-file --batch-all-objects --buffer --batch-check |
  grep blob |
  git cat-file --batch='%(objectname) %(rest)' |
  wc -c

Adding "--unordered" to the first command drops the runtime
in git.git from 24s to 3.5s.

  Side note: there are actually further speedups available
  for doing it all in-process now. Since we are outputting
  the object content during the actual pack iteration, we
  know where to find the object and could skip the extra
  lookup done by oid_object_info(). This patch stops short
  of that optimization since the underlying API isn't ready
  for us to make those sorts of direct requests.

So if --unordered is so much better, why not make it the
default? Two reasons:

  1. We've promised in the documentation that --batch-all-objects
     outputs in hash order. Since cat-file is plumbing,
     people may be relying on that default, and we can't
     change it.

  2. It's actually _slower_ for some cases. We have to
     compute the pack revindex to walk in pack order. And
     our de-duplication step uses an oidset, rather than a
     sort-and-dedup, which can end up being more expensive.
     If we're just accessing the type and size of each
     object, for example, like:

       git cat-file --batch-all-objects --buffer --batch-check

     my best-of-five warm cache timings go from 900ms to
     1100ms using --unordered. Though it's possible in a
     cold-cache or under memory pressure that we could do
     better, since we'd have better locality within the
     packfile.

And one final question: why is it "--unordered" and not
"--pack-order"? The answer is again two-fold:

  1. "pack order" isn't a well-defined thing across the
     whole set of objects. We're hitting loose objects, as
     well as objects in multiple packs, and the only
     ordering we're promising is _within_ a single pack. The
     rest is apparently random.

  2. The point here is optimization. So we don't want to
     promise any particular ordering, but only to say that
     we will choose an ordering which is likely to be
     efficient for accessing the object content. That leaves
     the door open for further changes in the future without
     having to add another compatibility option.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-13 13:48:31 -07:00
Jeff King
aa2f5ef500 t1006: test cat-file --batch-all-objects with duplicates
The test for --batch-all-objects in t1006 covers a variety
of object storage situations, but one thing it doesn't cover
is that we avoid mentioning duplicate objects. We won't have
any because running "git repack -ad" will have packed them
all and deleted the loose ones.

This does work (because we sort and de-dup the output list),
but it's good to include it in our test. And doubly so for
when we add an unordered mode which has to de-dup in a
different way.

Note that we cannot just re-create one of the objects, as
Git will omit the write of an object that is already
present. However, we can create a new pack with one of the
objects, which forces the duplication.

One alternative would be to just use "git repack -a" instead
of "-ad". But then _every_ object would be duplicated as
loose and packed, and we might miss a bug that omits packed
objects (because we'd show their loose counterparts).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-13 13:48:29 -07:00
brian m. carlson
8125a58b91 t: switch $_z40 to $ZERO_OID
Switch all uses of $_z40 to $ZERO_OID so that they work correctly with
larger hashes.  This commit was created by using the following sed
command to modify all files in the t directory except t/test-lib.sh:

  sed -i 's/\$_z40/$ZERO_OID/g'

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-14 11:02:00 +09:00
Nguyễn Thái Ngọc Duy
c680668d1a t/helper: merge test-genrandom into test-tool
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-03-27 08:45:47 -07:00
Ville Skyttä
2e3a16b279 Spelling fixes
<BAD>                     <CORRECTED>
    accidently                accidentally
    commited                  committed
    dependancy                dependency
    emtpy                     empty
    existance                 existence
    explicitely               explicitly
    git-upload-achive         git-upload-archive
    hierachy                  hierarchy
    indegee                   indegree
    intial                    initial
    mulitple                  multiple
    non-existant              non-existent
    precendence.              precedence.
    priviledged               privileged
    programatically           programmatically
    psuedo-binary             pseudo-binary
    soemwhere                 somewhere
    successfull               successful
    transfering               transferring
    uncommited                uncommitted
    unkown                    unknown
    usefull                   useful
    writting                  writing

Signed-off-by: Ville Skyttä <ville.skytta@iki.fi>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-08-11 14:35:42 -07:00
Jeff King
3115ee45c8 cat-file: sort and de-dup output of --batch-all-objects
The sorting we could probably live without, but printing
duplicates is just a hassle for the user, who must then
de-dup themselves (or risk a wrong answer if they are doing
something like counting objects with a particular property).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-26 09:24:42 -07:00
Jeff King
6a951937ae cat-file: add --batch-all-objects option
It can sometimes be useful to examine all objects in the
repository. Normally this is done with "git rev-list --all
--objects", but:

  1. That shows only reachable objects. You may want to look
     at all available objects.

  2. It's slow. We actually open each object to walk the
     graph. If your operation is OK with seeing unreachable
     objects, it's an order of magnitude faster to just
     enumerate the loose directories and pack indices.

You can do this yourself using "ls" and "git show-index",
but it's non-obvious.  This patch adds an option to
"cat-file --batch-check" to operate on all available
objects (rather than reading names from stdin).

This is based on a proposal by Charles Bailey to provide a
separate "git list-all-objects" command. That is more
orthogonal, as it splits enumerating the objects from
getting information about them. However, in practice you
will either:

  a. Feed the list of objects directly into cat-file anyway,
     so you can find out information about them. Keeping it
     in a single process is more efficient.

  b. Ask the listing process to start telling you more
     information about the objects, in which case you will
     reinvent cat-file's batch-check formatter.

Adding a cat-file option is simple and efficient. And if you
really do want just the object names, you can always do:

  git cat-file --batch-check='%(objectname)' --batch-all-objects

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-22 14:55:52 -07:00
Junio C Hamano
67f0b6f3b2 Merge branch 'dt/cat-file-follow-symlinks'
"git cat-file --batch(-check)" learned the "--follow-symlinks"
option that follows an in-tree symbolic link when asked about an
object via extended SHA-1 syntax, e.g. HEAD:RelNotes that points at
Documentation/RelNotes/2.5.0.txt.  With the new option, the command
behaves as if HEAD:Documentation/RelNotes/2.5.0.txt was given as
input instead.

* dt/cat-file-follow-symlinks:
  cat-file: add --follow-symlinks to --batch
  sha1_name: get_sha1_with_context learns to follow symlinks
  tree-walk: learn get_tree_entry_follow_symlinks
2015-06-01 12:45:16 -07:00
David Turner
122d53464b cat-file: add --follow-symlinks to --batch
This wires the in-repo-symlink following code through to the cat-file
builtin.  In the event of an out-of-repo link, cat-file will print
the link in a new format.

Signed-off-by: David Turner <dturner@twopensource.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-20 13:46:21 -07:00
Karthik Nayak
3e370f9faf t1006: add tests for git cat-file --allow-unknown-type
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-05-06 13:47:18 -07:00
Jeff King
99094a7ad4 t: fix trivial &&-chain breakage
These are tests which are missing a link in their &&-chain,
but during a setup phase. We may fail to notice failure in
commands that build the test environment, but these are
typically not expected to fail at all (but it's still good
to double-check that our test environment is what we
expect).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-20 10:20:14 -07:00
Junio C Hamano
b2132068c6 Merge branch 'jk/oi-delta-base'
Teach "cat-file --batch" to show delta-base object name for a
packed object that is represented as a delta.

* jk/oi-delta-base:
  cat-file: provide %(deltabase) batch format
  sha1_object_info_extended: provide delta base sha1s
2014-01-10 10:33:11 -08:00
Junio C Hamano
604ada435b Merge branch 'jk/cat-file-regression-fix'
"git cat-file --batch=", an admittedly useless command, did not
behave very well.

* jk/cat-file-regression-fix:
  cat-file: handle --batch format with missing type/size
  cat-file: pass expand_data to print_object_or_die
2013-12-27 14:58:11 -08:00
Jeff King
65ea9c3c3d cat-file: provide %(deltabase) batch format
It can be useful for debugging or analysis to see which
objects are stored as delta bases on top of others. This
information is available by running `git verify-pack`, but
that is extremely expensive (and is harder than necessary to
parse).

Instead, let's make it available as a cat-file query format,
which makes it fast and simple to get the bases for a subset
of the objects.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-26 11:54:26 -08:00
Jeff King
6554dfa97a cat-file: handle --batch format with missing type/size
Commit 98e2092 taught cat-file to stream blobs with --batch,
which requires that we look up the object type before
loading it into memory.  As a result, we now print the
object header from information in sha1_object_info, and the
actual contents from the read_sha1_file. We double-check
that the information we printed in the header matches the
content we are about to show.

Later, commit 93d2a60 allowed custom header lines for
--batch, and commit 5b08640 made type lookups optional. As a
result, specifying a header line without the type or size
means that we will not look up those items at all.

This causes our double-checking to erroneously die with an
error; we think the type or size has changed, when in fact
it was simply left at "0".

For the size, we can fix this by only doing the consistency
double-check when we have retrieved the size via
sha1_object_info. In the case that we have not retrieved the
value, that means we also did not print it, so there is
nothing for us to check that we are consistent with.

We could do the same for the type. However, besides our
consistency check, we also care about the type in deciding
whether to stream or not. So instead of handling the case
where we do not know the type, this patch instead makes sure
that we always trigger a type lookup when we are printing,
so that even a format without the type will stream as we
would in the normal case.

Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-12 11:31:25 -08:00
Junio C Hamano
c17fa972d3 Merge branch 'sb/sha1-loose-object-info-check-existence'
"git cat-file --batch-check=ok" did not check the existence of the
named object.

* sb/sha1-loose-object-info-check-existence:
  sha1_loose_object_info(): do not return success on missing object
2013-12-05 13:00:12 -08:00
Junio C Hamano
4ef8d1dd03 sha1_loose_object_info(): do not return success on missing object
Since 052fe5ea (sha1_loose_object_info: make type lookup optional,
2013-07-12), sha1_loose_object_info() returns happily without
checking if the object in question exists, which is not what the the
caller sha1_object_info_extended() expects; the caller does not even
bother checking the existence of the object itself.

Noticed-by: Sven Brauch <svenbrauch@googlemail.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-11-06 11:03:33 -08:00
Jeff King
97be04077f cat-file: only split on whitespace when %(rest) is used
Commit c334b87b (cat-file: split --batch input lines on whitespace,
2013-07-11) taught `cat-file --batch-check` to split input lines on
the first whitespace, and stash everything after the first token
into the %(rest) output format element.  It claimed:

   Object names cannot contain spaces, so any input with
   spaces would have resulted in a "missing" line.

But that is not correct.  Refs, object sha1s, and various peeling
suffixes cannot contain spaces, but some object names can. In
particular:

  1. Tree paths like "[<tree>]:path with whitespace"

  2. Reflog specifications like "@{2 days ago}"

  3. Commit searches like "rev^{/grep me}" or ":/grep me"

To remain backwards compatible, we cannot split on whitespace by
default, hence we will ship 1.8.4 with the commit reverted.

Resurrect its attempt but in a weaker form; only do the splitting
when "%(rest)" is used in the output format. Since that element did
not exist at all before c334b87, old scripts cannot be affected.

The existence of object names with spaces does mean that you
cannot reliably do:

  echo ":path with space and other data" |
  git cat-file --batch-check="%(objectname) %(rest)"

as it would split the path and feed only ":path" to get_sha1. But
that command is nonsensical. If you wanted to see "and other data"
in "%(rest)", git cannot possibly know where the filename ends and
the "rest" begins.

It might be more robust to have something like "-z" to separate the
input elements. But this patch is still a reasonable step before
having that.  It makes the easy cases easy; people who do not care
about %(rest) do not have to consider it, and the %(rest) code
handles the spaces and newlines of "rev-list --objects" correctly.

Hard cases remain hard but possible (if you might get whitespace in
your input, you do not get to use %(rest) and must split and join
the output yourself using more flexible tools). And most
importantly, it does not preclude us from having different splitting
rules later if a "-z" (or similar) option is added.  So we can make
the hard cases easier later, if we choose to.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-08-05 09:30:48 -07:00
Junio C Hamano
062aeee8aa Revert "cat-file: split --batch input lines on whitespace"
This reverts commit c334b87b30c1464a1ab563fe1fb8de5eaf0e5bac; the
update assumed that people only used the command to read from
"rev-list --objects" output, whose lines begin with a 40-hex object
name followed by a whitespace, but it turns out that scripts feed
random extended SHA-1 expressions (e.g. "HEAD:$pathname") in which
a whitespace has to be kept.
2013-08-02 09:29:30 -07:00
Jeff King
c334b87b30 cat-file: split --batch input lines on whitespace
If we get an input line to --batch or --batch-check that
looks like "HEAD foo bar", we will currently feed the whole
thing to get_sha1(). This means that to use --batch-check
with `rev-list --objects`, one must pre-process the input,
like:

  git rev-list --objects HEAD |
  cut -d' ' -f1 |
  git cat-file --batch-check

Besides being more typing and slightly less efficient to
invoke `cut`, the result loses information: we no longer
know which path each object was found at.

This patch teaches cat-file to split input lines at the
first whitespace. Everything to the left of the whitespace
is considered an object name, and everything to the right is
made available as the %(reset) atom. So you can now do:

  git rev-list --objects HEAD |
  git cat-file --batch-check='%(objectsize) %(rest)'

to collect object sizes at particular paths.

Even if %(rest) is not used, we always do the whitespace
split (which means you can simply eliminate the `cut`
command from the first example above).

This whitespace split is backwards compatible for any
reasonable input. Object names cannot contain spaces, so any
input with spaces would have resulted in a "missing" line.
The only input hurt is if somebody really expected input of
the form "HEAD is a fine-looking ref!" to fail; it will now
parse HEAD, and make "is a fine-looking ref!" available as
%(rest).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-07-12 09:18:42 -07:00