Commit Graph

52760 Commits

Author SHA1 Message Date
Jonathan Tan
a7e67c11b8 clone: check connectivity even if clone is partial
The commit that introduced the partial clone feature - 548719fbdc
("clone: partial clone", 2017-12-08) - excluded connectivity checks
for partial clones, but this also meant that it is possible for a clone
to succeed, yet not have all objects either present or promised.
Specifically, if cloning with --filter=blob:none from a repository that
has a tag pointing to a blob, and the blob is not sent in the packfile,
the clone will pass, even if the blob is not referenced by any tree in
the packfile.

Turn on connectivity checks for partial clone.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-09 12:37:38 -07:00
Jonathan Tan
a0c9016abd upload-pack: send refs' objects despite "filter"
A filter line in a request to upload-pack filters out objects regardless
of whether they are directly referenced by a "want" line or not. This
means that cloning with "--filter=blob:none" (or another filter that
excludes blobs) from a repository with at least one ref pointing to a
blob (for example, the Git repository itself) results in output like the
following:

    error: missing object referenced by 'refs/tags/junio-gpg-pub'

and if that particular blob is not referenced by a fetched tree, the
resulting clone fails fsck because there is no object from the remote to
vouch that the missing object is a promisor object.

Update both the protocol and the upload-pack implementation to include
all explicitly specified "want" objects in the packfile regardless of
the filter specification.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-09 12:37:38 -07:00
brian m. carlson
fa29f36d99 docs: correct RFC specifying email line length
The git send-email documentation specifies RFC 2821 (the SMTP RFC) as
providing line length limits, but the specification that restricts line
length to 998 octets is RFC 2822 (the email message format RFC).  Since
RFC 2822 has been obsoleted by RFC 5322, update the text to refer to RFC
5322 instead of RFC 2821.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-09 10:55:12 -07:00
brian m. carlson
e67a228cd8 send-email: automatically determine transfer-encoding
git send-email, when invoked without a --transfer-encoding option, sends
8bit data without a MIME version or a transfer encoding.  This has
several downsides.

First, unless the transfer encoding is specified, it defaults to 7bit,
meaning that non-ASCII data isn't allowed.  Second, if lines longer than
998 bytes are used, we will send an message that is invalid according to
RFC 5322.  The --validate option, which is the default, catches this
issue, but it isn't clear to many people how to resolve this.

To solve these issues, default the transfer encoding to "auto", so that
we explicitly specify 8bit encoding when lines don't exceed 998 bytes
and quoted-printable otherwise.  This means that we now always emit
Content-Transfer-Encoding and MIME-Version headers, so remove the
conditionals from this portion of the code.

It is unlikely that the unconditional inclusion of these two headers
will affect the deliverability of messages in anything but a positive
way, since MIME is already widespread and well understood by most email
programs.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-09 10:55:12 -07:00
brian m. carlson
f2d06fb13f send-email: accept long lines with suitable transfer encoding
With --validate (which is the default), we warn about lines exceeding
998 characters due to the limits specified in RFC 5322.  However, if
we're using a suitable transfer encoding (quoted-printable or base64),
we're guaranteed not to have lines exceeding 76 characters, so there's
no need to fail in this case.  The auto transfer encoding handles this
specific case, so accept it as well.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-09 10:55:12 -07:00
brian m. carlson
7a36987fff send-email: add an auto option for transfer encoding
For most patches, using a transfer encoding of 8bit provides good
compatibility with most servers and makes it as easy as possible to view
patches.  However, there are some patches for which 8bit is not a valid
encoding: RFC 5322 specifies that a message must not have lines
exceeding 998 octets.

Add a transfer encoding value, auto, which indicates that a patch should
use 8bit where allowed and quoted-printable otherwise.  Choose
quoted-printable instead of base64, since base64-encoded plain text is
treated as suspicious by some spam filters.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-09 10:55:12 -07:00
Kana Natsuno
1ab631647e userdiff: support new keywords in PHP hunk header
Recent version of PHP supports interface, trait, abstract class and
final class.  This patch fixes the PHP hunk header regexp to support
all of these keywords.

Signed-off-by: Kana Natsuno <dev@whileimautomaton.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-06 14:59:28 -07:00
Kana Natsuno
9992fbd7a1 t4018: add missing test cases for PHP
A later patch changes the built-in PHP pattern. These test cases
demonstrate aspects of the pattern that we do not want to change.

Signed-off-by: Kana Natsuno <dev@whileimautomaton.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-06 14:56:42 -07:00
Elijah Newren
327ac9cb9d t6036: add lots of detail for directory/file conflicts in recursive case
There was a discussion of problematic directory/file conflicts with
virtual merge bases on the mailing list years ago at
  https://public-inbox.org/git/AANLkTimwUQafGDrjxWrfU9uY1uKoFLJhxYs=vssOPqdf@mail.gmail.com/
Part of these corresponding tests made it into this testsuite.  However,
the more problematic one didn't.  And there are others that showcase the
problems even more.  Add a very lengthy explanation, some of it from that
email, describing the tradeoffs in picking a recursive merge-base when
you're dealing with an add/add directory/file conflict.

The solution picked years ago is relatively good, but there is the
potential to do even better, assuming we're willing to pay a certain
performance cost.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-06 14:45:26 -07:00
Beat Bolli
6aaded5509 builtin/config: work around an unsized array forward declaration
As reported here[0], Microsoft Visual Studio 2017.2 and "gcc -pedantic"
don't understand the forward declaration of an unsized static array.
They insist on an array size:

    d:\git\src\builtin\config.c(70,46): error C2133: 'builtin_config_options': unknown size

The thread [1] explains that this is due to the single-pass nature of
old compilers.

To work around this error, introduce the forward-declared function
usage_builtin_config() instead that uses the array
builtin_config_options only after it has been defined.

Also use this function in all other places where usage_with_options() is
called with the same arguments.

[0]: https://github.com/git-for-windows/git/issues/1735
[1]: https://groups.google.com/forum/#!topic/comp.lang.c.moderated/bmiF2xMz51U

Fixes https://github.com/git-for-windows/git/issues/1735

Reported-By: Karen Huang (via GitHub)
Signed-off-by: Beat Bolli <dev+git@drbeat.li>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-06 12:31:53 -07:00
Tobias Klauser
2e9957525e git-rebase--preserve-merges: fix formatting of todo help message
Part of the todo help message in git-rebase--preserve-merges.sh is
unnecessarily indented, making the message look weird.  Remove the
extra lines and trailing indent.

This was a minor regression introduced by d48f97aa ("rebase:
reindent function git_rebase__interactive", 2018-03-23) in the 2.18
timeframe.  The same issue exists in "rebase -i", but it is being
addressed separately as part of the rewrite of the subcommand into C.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Reviewed-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-06 12:09:27 -07:00
Jeff King
5e834a4f39 t5500: prettify non-commit tag tests
We don't need to use backslash continuation, as the "&&"
already provides continuation (and happily soaks up empty
lines between commands).

We can also expand the multi-line printf into a
here-document, which lets us use line breaks more naturally
(and avoids another continuation that required us to break
the natural indentation).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-06 10:52:02 -07:00
Mike Hommey
9d14ecf39d fast-import: do not call diff_delta() with empty buffer
We know diff_delta() returns NULL, saying "no good delta exists for
it", when fed an empty data.  Check the length of the data in the
caller to avoid such a call.

This incidentally reduces the number of attempted deltification we
see in the final statistics.

Signed-off-by: Mike Hommey <mh@glandium.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-06 09:46:12 -07:00
Taylor Blau
c707ded332 grep.c: extract show_line_header()
The grep code invokes show_line() to display the contents of a matched
or context line in its output. Part of this execution is to print a line
header that includes information such as the kind, the line- and
column-number and etc. of that match.

To prepare for the addition of an option to print only the matching
component(s) of a non-context line, we must prepare for the possibility
that a single line may contain multiple matching parts, and thus will
need multiple headers printed for a single line.

Extracting show_line_header allows us to do just that. In the subsequent
commit, it will be used within the colorization loop to print out only
the matching parts of a line, optionally with LFs delimiting
sub-matches.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 15:10:30 -07:00
Jonathan Tan
3390e42adb fetch-pack: support negotiation tip whitelist
During negotiation, fetch-pack eventually reports as "have" lines all
commits reachable from all refs. Allow the user to restrict the commits
sent in this way by providing a whitelist of tips; only the tips
themselves and their ancestors will be sent.

Both globs and single objects are supported.

This feature is only supported for protocols that support connect or
stateless-connect (such as HTTP with protocol v2).

This will speed up negotiation when the repository has multiple
relatively independent branches (for example, when a repository
interacts with multiple repositories, such as with linux-next [1] and
torvalds/linux [2]), and the user knows which local branch is likely to
have commits in common with the upstream branch they are fetching.

[1] https://kernel.googlesource.com/pub/scm/linux/kernel/git/next/linux-next/
[2] https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux/

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 15:00:41 -07:00
Jonathan Tan
cf1e7c0770 fetch-pack: write shallow, then check connectivity
When fetching, connectivity is checked after the shallow file is
updated. There are 2 issues with this: (1) the connectivity check is
only performed up to ancestors of existing refs (which is not thorough
enough if we were deepening an existing ref in the first place), and (2)
there is no rollback of the shallow file if the connectivity check
fails.

To solve (1), update the connectivity check to check the ancestry chain
completely in the case of a deepening fetch by refraining from passing
"--not --all" when invoking rev-list in connected.c.

To solve (2), have fetch_pack() perform its own connectivity check
before updating the shallow file. To support existing use cases in which
"git fetch-pack" is used to download objects without much regard as to
the connectivity of the resulting objects with respect to the existing
repository, the connectivity check is only done if necessary (that is,
the fetch is not a clone, and the fetch involves shallow/deepen
functionality). "git fetch" still performs its own connectivity check,
preserving correctness but sometimes performing redundant work. This
redundancy is mitigated by the fact that fetch_pack() reports if it has
performed a connectivity check itself, and if the transport supports
connect or stateless-connect, it will bubble up that report so that "git
fetch" knows not to perform the connectivity check in such a case.

This was noticed when a user tried to deepen an existing repository by
fetching with --no-shallow from a server that did not send all necessary
objects - the connectivity check as run by "git fetch" succeeded, but a
subsequent "git fsck" failed.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 14:57:44 -07:00
Jeff King
e674eb2528 ref-filter: avoid backend filtering with --ignore-case
When for-each-ref is used with --ignore-case, we expect
match_name_as_path() to do a case-insensitive match. But
there's an extra layer of filtering that happens before we
even get there. Since commit cfe004a5a9 (ref-filter: limit
traversal to prefix, 2017-05-22), we feed the prefix to the
ref backend so that it can optimize the ref iteration.

There's no mechanism for us to tell the backend we're matching
case-insensitively.  Nor is there likely to be one anytime soon,
since the packed backend relies on binary-searching the sorted list
of refs. Let's just punt on this case. The extra filtering is an
optimization that we simply can't do. We'll still give the correct
answer via the filtering in match_name_as_path().

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 14:49:37 -07:00
Aleksandr Makarov
639ab5efa1 for-each-ref: consistently pass WM_IGNORECASE flag
The match_name_as_path() function learned to set
WM_IGNORECASE in the "flags" field when the user passed
--ignore-case. But it forgot to actually pass the flags to
wildmatch()!

As a result, the --ignore-case feature has been broken since
it was added in 3bb16a8bf2 (tag, branch, for-each-ref: add
--ignore-case for sorting and filtering, 2016-12-04). We
didn't notice because we added tests only for git-branch and
git-tag. Whereas git-for-each-ref has slightly different
matching rules, and thus uses a different function (the
related function match_pattern() does it correctly).

Incidentally, this also caused clang's scan-build to
complain about the code; the assignment to "flags" was dead
code.

Note that we can't flip the test in t6300 to expect_success
yet. There's another bug, which will be dealt with in the
next patch.

Commit-message-by: Jeff King <peff@peff.net>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 14:49:15 -07:00
Jeff King
ee0f3e22c6 t6300: add a test for --ignore-case
The --ignore-case option was added by 3bb16a8bf2 (tag,
branch, for-each-ref: add --ignore-case for sorting and
filtering, 2016-12-04), but it was never tested. And indeed,
it does not work due to multiple bugs (which will be fixed
in subsequent patches).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 14:49:13 -07:00
Elijah Newren
651f7f3a1b t6042: add testcase covering long chains of rename conflicts
Each rename is a lego: the source side could be connected to a delete or
another rename, and the destination side could be connected to a rename or a
conflicting add.  Previous tests combined these to get e.g.
rename/rename(1to2)/add/add, rename/rename(2to1)/delete/delete, and
rename/add/delete.  But we can also build bigger chains of conflicts.  Add a
testcase demonstrating this.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 14:47:47 -07:00
Elijah Newren
eee73388f2 t6042: add testcase covering rename/rename(2to1)/delete/delete conflict
If either side of a rename/rename(2to1) conflict is itself also involved
in a rename/delete conflict, then the conflict is a little more complex;
we can even have what I'd call a rename/rename(2to1)/delete/delete
conflict.  (In some ways, this is similar to a rename/rename(1to2)/add/add
conflict, as added in commit 3672c97148 ("merge-recursive: Fix working
copy handling for rename/rename/add/add", 2011-08-11)).  Add a testcase
for such a conflict.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 14:47:44 -07:00
Elijah Newren
11d9ade10e t6042: add testcase covering rename/add/delete conflict type
If a file is renamed on one side of history, and the other side of history
both deletes the original file and adds a new unrelated file in the way of
the rename, then we have what I call a rename/add/delete conflict.  Add a
testcase covering this scenario.

Reported-by: Robert Dailey <rcdailey.lists@gmail.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 14:47:42 -07:00
Elijah Newren
451a3abc26 t6036: add a failed conflict detection case with conflicting types
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 14:43:43 -07:00
Elijah Newren
a79968bed1 t6036: add a failed conflict detection case with submodule add/add
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 14:43:43 -07:00
Elijah Newren
d4d1718080 t6036: add a failed conflict detection case with submodule modify/modify
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 14:43:42 -07:00
Elijah Newren
81f5a2ce7b t6036: add a failed conflict detection case with symlink add/add
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 14:43:42 -07:00
Elijah Newren
c6d3dd5daf t6036: add a failed conflict detection case with symlink modify/modify
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 14:43:42 -07:00
Elijah Newren
58f4d1b961 t6044: verify that merges expected to abort actually abort
t6044 has lots of tests for verifying that merge will abort as expected
when there are changes staged before the merge starts.  However, it only
checked for non-zero exit code, which could mean that the merge ran to
completion with conflicts.  Check that the merge was actually correctly
aborted, i.e. that .git/MERGE_HEAD is not present.

This changes one of the tests from expect_success to expect_failure.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 13:13:18 -07:00
Elijah Newren
1b9fbefbe0 index_has_changes(): avoid assuming operating on the_index
Modify index_has_changes() to take a struct istate* instead of just
operating on the_index.  This is only a partial conversion, though,
because we call do_diff_cache() which implicitly assumes work is to be
done on the_index.  Ongoing work is being done elsewhere to do the
remainder of the conversion, and thus is not duplicated here.  Instead,
a simple check is put in place until that work is complete.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 13:13:18 -07:00
Elijah Newren
cffbfad50d read-cache.c: move index_has_changes() from merge.c
Since index_has_change() is an index-related function, move it to
read-cache.c, only modifying it to avoid uses of the active_cache and
active_nr macros.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 13:13:17 -07:00
Eric Sunshine
e7eb15faca t7201: drop pointless "exit 0" at end of subshell
This test employs a for-loop inside a subshell and correctly aborts the
loop and fails the test overall (via "exit 1") if any iteration of the
for-loop fails. Otherwise, it exits the subshell with an explicit but
entirely unnecessary "exit 0", presumably to indicate that all
iterations of the loop succeeded. The &&-chain is broken between the
for-loop and the "exit 0". Rather than fixing the &&-chain, just drop
the pointless "exit 0".

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 12:38:05 -07:00
Eric Sunshine
f1e1239811 t6036: fix broken "merge fails but has appropriate contents" tests
These tests reference non-existent object "c" when they really mean to
be referencing "C", however, these errors went unnoticed due to a broken
&&-chain later in the tests. Fix these errors, as well as the broken
&&-chains behind which they hid.

Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 12:38:05 -07:00
Eric Sunshine
431f4a26b5 t5505: modernize and simplify hard-to-digest test
This test uses a subshell within a subshell but is formatted in such a
way as to suggests that the inner subshell is a sibling rather than a
child, which makes it difficult to digest the test's structure and
intent.

Worse, the inner subshell performs cleanup of actions from earlier in
the test, however, a failure between the initial actions and the cleanup
will prevent the cleanup from taking place.

Fix these problems by modernizing and simplifying the test and by using
test_when_finished() for the cleanup action.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 12:38:05 -07:00
Eric Sunshine
fb23bd7af2 t5406: use write_script() instead of birthing shell script manually
Take advantage of write_script() to abstract-away details of shell
script creation, thus allowing the reader to focus on script content.
Readability benefits, particularly in this case, since the script body
was buried in a noisy one-liner subshell responsible for emitting
boilerplate and body.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 12:38:04 -07:00
Eric Sunshine
fbd6ef273e t5405: use test_must_fail() instead of checking exit code manually
This test expects "git push" to fail, thus it manually inverts that
local expected failure into a successful exit code for the test overall.
In doing so, it intentionally breaks the &&-chain. Modernize by
replacing manual exit code management with test_must_fail() and a normal
&&-chain.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 12:38:04 -07:00
Eric Sunshine
e5d7e9f516 t/lib-submodule-update: fix "absorbing" test
This test has been dysfunctional since it was added by 259f3ee296
(lib-submodule-update.sh: define tests for recursing into submodules,
2017-03-14), however, the problem went unnoticed due to a broken
&&-chain.

The test wants to verify that replacing a submodule containing a .git
directory will absorb the .git directory into the .git/modules/ of the
superproject, and then replace the working tree content appropriate to
the superproject. It is, therefore, incorrect to check if the
submodule content still exists since the submodule will have been
replaced by the content of the superproject.

Fix this by removing the submodule content check, which also happens
to be the line that broke the &&-chain.

While at it, fix broken &&-chains in a couple neighboring tests.

Helped-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 12:38:04 -07:00
Eric Sunshine
02779185d5 t: drop unnecessary terminating semicolon in subshell
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 12:38:04 -07:00
Eric Sunshine
ed6c994af4 t: use sane_unset() rather than 'unset' with broken &&-chain
These tests intentionally break the &&-chain after using 'unset' since
they don't know if 'unset' will succeed or fail and don't want a local
'unset' failure to fail the test overall. We can do better by using
sane_unset(), which can be linked into the &&-chain as usual.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 12:38:04 -07:00
Eric Sunshine
0590ff26c4 t: use test_write_lines() instead of series of 'echo' commands
These tests employ a noisy subshell (with missing &&-chain) to feed
input into Git commands or files:

    (echo a; echo b; echo c) | git some-command ...

Simplify by taking advantage of test_write_lines():

    test_write_lines a b c | git some-command ...

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 12:38:04 -07:00
Eric Sunshine
8327974859 t: use test_might_fail() instead of manipulating exit code manually
These tests manually coerce the exit code of invoked commands to
"success" when they don't care if the command succeeds or fails since
failure of those commands should not cause the test to fail overall.
In doing so, they intentionally break the &&-chain. Modernize by
replacing manual exit code management with test_might_fail() and a
normal &&-chain.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 12:38:04 -07:00
Jameson Miller
8616a2d0cb block alloc: add validations around cache_entry lifecyle
Add an option (controlled by an environment variable) perform extra
validations on mem_pool allocated cache entries. When set:

  1) Invalidate cache_entry memory when discarding cache_entry.

  2) When discarding index_state struct, verify that all cache_entries
     were allocated from expected mem_pool.

  3) When discarding mem_pools, invalidate mem_pool memory.

This should provide extra checks that mem_pools and their allocated
cache_entries are being used as expected.

Signed-off-by: Jameson Miller <jamill@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 10:58:27 -07:00
Jameson Miller
8e72d67529 block alloc: allocate cache entries from mem_pool
When reading large indexes from disk, a portion of the time is
dominated in malloc() calls. This can be mitigated by allocating a
large block of memory and manage it ourselves via memory pools.

This change moves the cache entry allocation to be on top of memory
pools.

Design:

The index_state struct will gain a notion of an associated memory_pool
from which cache_entries will be allocated from. When reading in the
index from disk, we have information on the number of entries and
their size, which can guide us in deciding how large our initial
memory allocation should be. When an index is discarded, the
associated memory_pool will be discarded as well - so the lifetime of
a cache_entry is tied to the lifetime of the index_state that it was
allocated for.

In the case of a Split Index, the following rules are followed. 1st,
some terminology is defined:

Terminology:
  - 'the_index': represents the logical view of the index

  - 'split_index': represents the "base" cache entries. Read from the
    split index file.

'the_index' can reference a single split_index, as well as
cache_entries from the split_index. `the_index` will be discarded
before the `split_index` is.  This means that when we are allocating
cache_entries in the presence of a split index, we need to allocate
the entries from the `split_index`'s memory pool.  This allows us to
follow the pattern that `the_index` can reference cache_entries from
the `split_index`, and that the cache_entries will not be freed while
they are still being referenced.

Managing transient cache_entry structs:
Cache entries are usually allocated for an index, but this is not always
the case. Cache entries are sometimes allocated because this is the
type that the existing checkout_entry function works with. Because of
this, the existing code needs to handle cache entries associated with an
index / memory pool, and those that only exist transiently. Several
strategies were contemplated around how to handle this:

Chosen approach:
An extra field was added to the cache_entry type to track whether the
cache_entry was allocated from a memory pool or not. This is currently
an int field, as there are no more available bits in the existing
ce_flags bit field. If / when more bits are needed, this new field can
be turned into a proper bit field.

Alternatives:

1) Do not include any information about how the cache_entry was
allocated. Calling code would be responsible for tracking whether the
cache_entry needed to be freed or not.
  Pro: No extra memory overhead to track this state
  Con: Extra complexity in callers to handle this correctly.

The extra complexity and burden to not regress this behavior in the
future was more than we wanted.

2) cache_entry would gain knowledge about which mem_pool allocated it
  Pro: Could (potentially) do extra logic to know when a mem_pool no
       longer had references to any cache_entry
  Con: cache_entry would grow heavier by a pointer, instead of int

We didn't see a tangible benefit to this approach

3) Do not add any extra information to a cache_entry, but when freeing a
   cache entry, check if the memory exists in a region managed by existing
   mem_pools.
  Pro: No extra memory overhead to track state
  Con: Extra computation is performed when freeing cache entries

We decided tracking and iterating over known memory pool regions was
less desirable than adding an extra field to track this stae.

Signed-off-by: Jameson Miller <jamill@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 10:58:27 -07:00
Jameson Miller
0e58301d81 mem-pool: fill out functionality
Add functions for:

    - combining two memory pools

    - determining if a memory address is within the range managed by a
      memory pool

These functions will be used by future commits.

Signed-off-by: Jameson Miller <jamill@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 10:58:27 -07:00
Jameson Miller
158dfeff3d mem-pool: add life cycle management functions
Add initialization and discard functions to mem_pool type. As the
memory allocated by mem_pool can now be freed, we also track the large
allocations.

If the there are existing mp_blocks in the mem_poo's linked list of
mp_blocksl, then the mp_block for a large allocation is inserted
behind the head block. This is because only the head mp_block is considered
when searching for availble space. This results in the following
desirable properties:

1) The mp_block allocated for the large request will not be included
not included in the search for available in future requests, the large
mp_block is sized for the specific request and does not contain any
spare space.

2) The head mp_block will not bumped from considation for future
memory requests just because a request for a large chunk of memory
came in.

These changes are in preparation for a future commit that will utilize
creating and discarding memory pool.

Signed-off-by: Jameson Miller <jamill@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 10:58:27 -07:00
Jameson Miller
8fb8e3f636 mem-pool: only search head block for available space
Instead of searching all memory blocks for available space to fulfill
a memory request, only search the head block. If the head block does
not have space, assume that previous block would most likely not be
able to fulfill request either. This could potentially lead to more
memory fragmentation, but also avoids searching memory blocks that
probably will not be able to fulfill request.

This pattern will benefit consumers that are able to generate a good
estimate for how much memory will be needed, or if they are performing
fixed sized allocations, so that once a block is exhausted it will
never be able to fulfill a future request.

Signed-off-by: Jameson Miller <jamill@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 10:58:27 -07:00
Jameson Miller
a849735bfb block alloc: add lifecycle APIs for cache_entry structs
It has been observed that the time spent loading an index with a large
number of entries is partly dominated by malloc() calls. This change
is in preparation for using memory pools to reduce the number of
malloc() calls made to allocate cahce entries when loading an index.

Add an API to allocate and discard cache entries, abstracting the
details of managing the memory backing the cache entries. This commit
does actually change how memory is managed - this will be done in a
later commit in the series.

This change makes the distinction between cache entries that are
associated with an index and cache entries that are not associated with
an index. A main use of cache entries is with an index, and we can
optimize the memory management around this. We still have other cases
where a cache entry is not persisted with an index, and so we need to
handle the "transient" use case as well.

To keep the congnitive overhead of managing the cache entries, there
will only be a single discard function. This means there must be enough
information kept with the cache entry so that we know how to discard
them.

A summary of the main functions in the API is:

make_cache_entry: create cache entry for use in an index. Uses specified
                  parameters to populate cache_entry fields.

make_empty_cache_entry: Create an empty cache entry for use in an index.
                        Returns cache entry with empty fields.

make_transient_cache_entry: create cache entry that is not used in an
                            index. Uses specified parameters to populate
                            cache_entry fields.

make_empty_transient_cache_entry: create cache entry that is not used in
                                  an index. Returns cache entry with
                                  empty fields.

discard_cache_entry: A single function that knows how to discard a cache
                     entry regardless of how it was allocated.

Signed-off-by: Jameson Miller <jamill@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 10:58:27 -07:00
Jameson Miller
825ed4d9a0 read-cache: teach make_cache_entry to take object_id
Teach make_cache_entry function to take object_id instead of a SHA-1.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 10:58:15 -07:00
Jameson Miller
768d796506 read-cache: teach refresh_cache_entry to take istate
Refactor refresh_cache_entry() to work on a specific index, instead of
implicitly using the_index. This is in preparation for making the
make_cache_entry function apply to a specific index.

Signed-off-by: Jameson Miller <jamill@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 10:58:15 -07:00
Ramsay Jones
fb16287719 fsck: check skiplist for object in fsck_blob()
Since commit ed8b10f631 ("fsck: check .gitmodules content", 2018-05-02),
fsck will issue an error message for '.gitmodules' content that cannot
be parsed correctly. This is the case, even when the corresponding blob
object has been included on the skiplist. For example, using the cgit
repository, we see the following:

  $ git fsck
  Checking object directories: 100% (256/256), done.
  error: bad config line 5 in blob .gitmodules
  error in blob 51dd1eff1edc663674df9ab85d2786a40f7ae3a5: gitmodulesParse: could not parse gitmodules blob
  Checking objects: 100% (6626/6626), done.
  $

  $ git config fsck.skiplist '.git/skip'
  $ echo 51dd1eff1edc663674df9ab85d2786a40f7ae3a5 >.git/skip
  $

  $ git fsck
  Checking object directories: 100% (256/256), done.
  error: bad config line 5 in blob .gitmodules
  Checking objects: 100% (6626/6626), done.
  $

Note that the error message issued by the config parser is still
present, despite adding the object-id of the blob to the skiplist.

One solution would be to provide a means of suppressing the messages
issued by the config parser. However, given that (logically) we are
asking fsck to ignore this object, a simpler approach is to just not
call the config parser if the object is to be skipped. Add a check to
the 'fsck_blob()' processing function, to determine if the object is
on the skiplist and, if so, exit the function early.

Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 09:49:44 -07:00
Jeff King
de6bd9e3ea fsck: silence stderr when parsing .gitmodules
If there's a parsing error we'll already report it via the
usual fsck report() function (or not, if the user has asked
to skip this object or warning type). The error message from
the config parser just adds confusion. Let's suppress it.

Note that we didn't test this case at all, so I've added
coverage in t7415. We may end up toning down or removing
this fsck check in the future. So take this test as checking
what happens now with a focus on stderr, and not any
ironclad guarantee that we must detect and report parse
failures in the future.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 09:36:41 -07:00