gitweb.git
commit-reach.c: allow paint_down_to_common to handle... Stefan Beller Wed, 14 Nov 2018 00:12:51 +0000 (16:12 -0800)

commit-reach.c: allow paint_down_to_common to handle any repo

As the function is file local and not widely used, migrate it all at once.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

commit: allow parse_commit* to handle any repoStefan Beller Wed, 14 Nov 2018 00:12:50 +0000 (16:12 -0800)

commit: allow parse_commit* to handle any repo

Just like the previous commit, parse_commit and friends are used a lot
and are found in new patches, so we cannot change their signature easily.

Re-introduce these function prefixed with 'repo_' that take a repository
argument and keep the original as a shallow macro.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

object: parse_object to honor its repository argumentStefan Beller Wed, 14 Nov 2018 00:12:49 +0000 (16:12 -0800)

object: parse_object to honor its repository argument

In 8e4b0b6047 (object.c: allow parse_object to handle
arbitrary repositories, 2018-06-28), we forgot to pass the
repository down to the read_object_file.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

object-store: prepare has_{sha1, object}_file to handle... Stefan Beller Wed, 14 Nov 2018 00:12:48 +0000 (16:12 -0800)

object-store: prepare has_{sha1, object}_file to handle any repo

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

object-store: prepare read_object_file to deal with... Stefan Beller Wed, 14 Nov 2018 00:12:47 +0000 (16:12 -0800)

object-store: prepare read_object_file to deal with any repo

As read_object_file is a widely used function (which is also regularly used
in new code in flight between master..pu), changing its signature is painful
is hard, as other series in flight rely on the original signature. It would
burden the maintainer if we'd just change the signature.

Introduce repo_read_object_file which takes the repository argument, and
hide the original read_object_file as a macro behind
NO_THE_REPOSITORY_COMPATIBILITY_MACROS, similar to
e675765235 (diff.c: remove implicit dependency on the_index, 2018-09-21)

Add a coccinelle patch to convert existing callers, but do not apply
the resulting patch to keep the diff of this patch small.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

object-store: allow read_object_file_extended to read... Stefan Beller Wed, 14 Nov 2018 00:12:46 +0000 (16:12 -0800)

object-store: allow read_object_file_extended to read from any repo

read_object_file_extended is not widely used, so migrate it all at once.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

push: change needlessly ambiguous example in errorÆvar Arnfjörð Bjarmason Tue, 13 Nov 2018 20:39:09 +0000 (20:39 +0000)

push: change needlessly ambiguous example in error

Change an example push added in b55e677522 ("push: introduce new
push.default mode "simple"", 2012-04-24) to always mean the same thing
whether the current setting happens to be "simple" or not.

This error is only emitted under "simple", but message is explaining
to the user that they can get two sorts of different behaviors by
these two invocations.

Let's use "git push <remote> HEAD" which always means push the current
branch name to that remote, instead of "git push <remote>
<current-branch-name>" which will do that under "simple", but is not
guaranteed to do under "upstream".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

hash: add an SHA-256 implementation using OpenSSLbrian m. carlson Wed, 14 Nov 2018 04:09:38 +0000 (04:09 +0000)

hash: add an SHA-256 implementation using OpenSSL

We already have OpenSSL routines available for SHA-1, so add routines
for SHA-256 as well.

On a Core i7-6600U, this SHA-256 implementation compares favorably to
the SHA1DC SHA-1 implementation:

SHA-1: 157 MiB/s (64 byte chunks); 337 MiB/s (16 KiB chunks)
SHA-256: 165 MiB/s (64 byte chunks); 408 MiB/s (16 KiB chunks)

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

sha256: add an SHA-256 implementation using libgcryptbrian m. carlson Wed, 14 Nov 2018 04:09:37 +0000 (04:09 +0000)

sha256: add an SHA-256 implementation using libgcrypt

Generally, one gets better performance out of cryptographic routines
written in assembly than C, and this is also true for SHA-256. In
addition, most Linux distributions cannot distribute Git linked against
OpenSSL for licensing reasons.

Most systems with GnuPG will also have libgcrypt, since it is a
dependency of GnuPG. libgcrypt is also faster than the SHA1DC
implementation for messages of a few KiB and larger.

For comparison, on a Core i7-6600U, this implementation processes 16 KiB
chunks at 355 MiB/s while SHA1DC processes equivalent chunks at 337
MiB/s.

In addition, libgcrypt is licensed under the LGPL 2.1, which is
compatible with the GPL. Add an implementation of SHA-256 that uses
libgcrypt.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Add a base implementation of SHA-256 supportbrian m. carlson Wed, 14 Nov 2018 04:09:36 +0000 (04:09 +0000)

Add a base implementation of SHA-256 support

SHA-1 is weak and we need to transition to a new hash function. For
some time, we have referred to this new function as NewHash. Recently,
we decided to pick SHA-256 as NewHash. The reasons behind the choice of
SHA-256 are outlined in the thread starting at [1] and in the commit
history for the hash function transition document.

Add a basic implementation of SHA-256 based off libtomcrypt, which is in
the public domain. Optimize it and restructure it to meet our coding
standards. Pull in the update and final functions from the SHA-1 block
implementation, as we know these function correctly with all compilers.
This implementation is slower than SHA-1, but more performant
implementations will be introduced in future commits.

Wire up SHA-256 in the list of hash algorithms, and add a test that the
algorithm works correctly.

Note that with this patch, it is still not possible to switch to using
SHA-256 in Git. Additional patches are needed to prepare the code to
handle a larger hash algorithm and further test fixes are needed.

[1] https://public-inbox.org/git/20180609224913.GC38834@genre.crustytoothpaste.net/

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

commit-graph: convert to using the_hash_algobrian m. carlson Wed, 14 Nov 2018 04:09:35 +0000 (04:09 +0000)

commit-graph: convert to using the_hash_algo

Instead of using hard-coded constants for object sizes, use
the_hash_algo to look them up. In addition, use a function call to look
up the object ID version and produce the correct value. For now, we use
version 1, which means to use the default algorithm used in the rest of
the repository.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/helper: add a test helper to compute hash speedbrian m. carlson Wed, 14 Nov 2018 04:09:34 +0000 (04:09 +0000)

t/helper: add a test helper to compute hash speed

Add a utility (which is less for the testsuite and more for developers)
that can compute hash speeds for whatever hash algorithms are
implemented. This allows developers to test their personal systems to
determine the performance characteristics of various algorithms.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

sha1-file: add a constant for hash block sizebrian m. carlson Wed, 14 Nov 2018 04:09:33 +0000 (04:09 +0000)

sha1-file: add a constant for hash block size

There is one place we need the hash algorithm block size: the HMAC code
for push certs. Expose this constant in struct git_hash_algo and expose
values for SHA-1 and for the largest value of any hash.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t: make the sha1 test-tool helper genericbrian m. carlson Wed, 14 Nov 2018 04:09:32 +0000 (04:09 +0000)

t: make the sha1 test-tool helper generic

Since we're going to have multiple hash algorithms to test, it makes
sense to share as much of the test code as possible. Convert the sha1
helper for the test-tool to be generic and move it out into its own
module. This will allow us to share most of this code with our NewHash
implementation.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t: add basic tests for our SHA-1 implementationbrian m. carlson Wed, 14 Nov 2018 04:09:31 +0000 (04:09 +0000)

t: add basic tests for our SHA-1 implementation

We have in the past had some unfortunate endianness issues with some
SHA-1 implementations we ship, especially on big-endian machines. Add
an explicit test using the test helper to catch these issues and point
them out prominently. This test can also be used as a staging ground
for people testing additional algorithms to verify that their
implementations are working as expected.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

cache: make hashcmp and hasheq work with larger hashesbrian m. carlson Wed, 14 Nov 2018 04:09:30 +0000 (04:09 +0000)

cache: make hashcmp and hasheq work with larger hashes

In 183a638b7d ("hashcmp: assert constant hash size", 2018-08-23), we
modified hashcmp to assert that the hash size was always 20 to help it
optimize and inline calls to memcmp. In a future series, we replaced
many calls to hashcmp and oidcmp with calls to hasheq and oideq to
improve inlining further.

However, we want to support hash algorithms other than SHA-1, namely
SHA-256. When doing so, we must handle the case where these values are
32 bytes long as well as 20. Adjust hashcmp to handle two cases:
20-byte matches, and maximum-size matches. Therefore, when we include
SHA-256, we'll automatically handle it properly, while at the same time
teaching the compiler that there are only two possible options to
consider. This will allow the compiler to write the most efficient
possible code.

Copy similar code into hasheq and perform an identical transformation.
At least with GCC 8.2.0, making hasheq defer to hashcmp when there are
two branches prevents the compiler from inlining the comparison, while
the code in this patch is inlined properly. Add a comment to avoid an
accidental performance regression from well-intentioned refactoring.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

hex: introduce functions to print arbitrary hashesbrian m. carlson Wed, 14 Nov 2018 04:09:29 +0000 (04:09 +0000)

hex: introduce functions to print arbitrary hashes

Currently, we have functions that turn an arbitrary SHA-1 value or an
object ID into hex format, either using a static buffer or with a
user-provided buffer. Add variants of these functions that can handle
an arbitrary hash algorithm, specified by constant. Update the
documentation as well.

While we're at it, remove the "extern" declaration from this family of
functions, since it's not needed and our style now recommends against
it.

We use the variant taking the algorithm structure pointer as the
internal variant, since taking an algorithm pointer is the easiest way
to handle all of the variants in use.

Note that we maintain these functions because there are hashes which
must change based on the hash algorithm in use but are not object IDs
(such as pack checksums).

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-compat-util: prefer poll.h to sys/poll.hĐoàn Trần Công Danh Wed, 14 Nov 2018 01:10:43 +0000 (08:10 +0700)

git-compat-util: prefer poll.h to sys/poll.h

POSIX specifies that <poll.h> is the correct header for poll(2)
whereas <sys/poll.h> is only needed for some old libc.

Let's follow the POSIX way by default.

This effectively eliminates musl's warning:

warning redirecting incorrect #include <sys/poll.h> to <poll.h>

Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff: align move detection error handling with other... Stefan Beller Tue, 13 Nov 2018 21:33:57 +0000 (13:33 -0800)

diff: align move detection error handling with other options

This changes the error handling for the options --color-moved-ws
and --color-moved-ws to be like the rest of the options.

Move the die() call out of parse_color_moved_ws into the parsing
of command line options. As the function returns a bit field, change
its signature to return an unsigned instead of an int; add a new bit
to signal errors. Once the error is signaled, we discard the other
bits, such that it doesn't matter if the error bit overlaps with any
other bit.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

push doc: document the DWYM behavior pushing to unquali... Ævar Arnfjörð Bjarmason Tue, 13 Nov 2018 19:52:45 +0000 (19:52 +0000)

push doc: document the DWYM behavior pushing to unqualified <dst>

Document the DWYM behavior that kicks in when pushing to an
unqualified <dst> reference.

This behavior was added in f88395ac23 ("Renaming push.", 2005-08-03)
and f8aae12034 ("push: allow unqualified dest refspecs to DWIM",
2008-04-23), and somewhat documented in bb9fca80ce ("git-push: Update
description of refspecs and add examples", 2007-06-09), but has never
been fully documented.

The closest we got to having documented it was the description in the
commit message for f8aae12034, which I've borrowed from in writing
this documentation.

Let's also refer to this new documentation from the existing
documentation we had (added in bb9fca80ce).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

push: test that <src> doesn't DWYM if <dst> is unqualifiedÆvar Arnfjörð Bjarmason Tue, 13 Nov 2018 19:52:44 +0000 (19:52 +0000)

push: test that <src> doesn't DWYM if <dst> is unqualified

Add a test asserting that "git push origin <src>:<dst>" where <src> is
a branch, tag, tree or blob in refs/remotes/* doesn't DWYM when <dst>
is unqualified. This has never been the case, but there haven't been
any tests for this behavior.

See f88395ac23 ("Renaming push.", 2005-08-03), bb9fca80ce ("git-push:
Update description of refspecs and add examples", 2007-06-09) and
f8aae12034 ("push: allow unqualified dest refspecs to DWIM",
2008-04-23) which are most relevant commits that have changed or
documented the behavior of the DWYM feature in the past.

These tests were originally meant to lead up to a patch that made
refs/remotes/* on the LHS imply refs/heads/* on the RHS, see [1]. That
patch proved controversial and may not ever land in git.git, but we
should have the tests that remind us what the current behavior is in
case it's ever changed.

1. https://public-inbox.org/git/20181026230741.23321-8-avarab@gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

push: add an advice on unqualified <dst> pushÆvar Arnfjörð Bjarmason Tue, 13 Nov 2018 19:52:43 +0000 (19:52 +0000)

push: add an advice on unqualified <dst> push

Add an advice to the recently improved error message added in
f8aae12034 ("push: allow unqualified dest refspecs to DWIM",
2008-04-23).

Now with advice.pushUnqualifiedRefName=true (on by default) we show a
hint about how to proceed:

$ ./git-push avar v2.19.0^{commit}:newbranch -n
error: The destination you provided is not a full refname (i.e.,
starting with "refs/"). We tried to guess what you meant by:

- Looking for a ref that matches 'newbranch' on the remote side.
- Checking if the <src> being pushed ('v2.19.0^{commit}')
is a ref in "refs/{heads,tags}/". If so we add a corresponding
refs/{heads,tags}/ prefix on the remote side.

Neither worked, so we gave up. You must fully qualify the ref.
hint: The <src> part of the refspec is a commit object.
hint: Did you mean to create a new branch by pushing to
hint: 'v2.19.0^{commit}:refs/heads/newbranch'?
error: failed to push some refs to 'git@github.com:avar/git.git'

When trying to push a tag, tree or a blob we suggest that perhaps the
user meant to push them to refs/tags/ instead.

The if/else duplication for all of OBJ_{COMMIT,TAG,TREE,BLOB} is
unfortunate, but is required to correctly mark the messages for
translation. See the discussion in
<87r2gxebsi.fsf@evledraar.gmail.com> about that.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

push: move unqualified refname error into a functionÆvar Arnfjörð Bjarmason Tue, 13 Nov 2018 19:52:42 +0000 (19:52 +0000)

push: move unqualified refname error into a function

A follow-up change will extend this error message with the advice
facility. Doing so would make the indentation too deeply nested for
comfort. So let's split this into a helper function.

There's no changes to the wording here. Just code moving &
re-indentation, and re-flowing the "TRANSLATORS" comment.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

push: improve the error shown on unqualified <dst>... Ævar Arnfjörð Bjarmason Tue, 13 Nov 2018 19:52:41 +0000 (19:52 +0000)

push: improve the error shown on unqualified <dst> push

Improve the error message added in f8aae12034 ("push: allow
unqualified dest refspecs to DWIM", 2008-04-23), which before this
change looks like this:

$ git push avar v2.19.0^{commit}:newbranch -n
error: unable to push to unqualified destination: newbranch
The destination refspec neither matches an existing ref on the remote nor
begins with refs/, and we are unable to guess a prefix based on the source ref.
error: failed to push some refs to 'git@github.com:avar/git.git'

This message needed to be read very carefully to spot how to fix the
error, i.e. to push to refs/heads/newbranch. Now the message will look
like this instead:

$ ./git-push avar v2.19.0^{commit}:newbranch -n
error: The destination you provided is not a full refname (i.e.,
starting with "refs/"). We tried to guess what you meant by:

- Looking for a ref that matches 'newbranch' on the remote side.
- Checking if the <src> being pushed ('v2.19.0^{commit}')
is a ref in "refs/{heads,tags}/". If so we add a corresponding
refs/{heads,tags}/ prefix on the remote side.

Neither worked, so we gave up. You must fully qualify the ref.
error: failed to push some refs to 'git@github.com:avar/git.git'

This improvement is the result of on-list discussion in [1] and [2],
as well as my own fixes / reformatting / phrasing on top.

The suggestion by Jeff on-list was to make that second bullet point
"Looking at the refname of the local source.". The version being added
here is more verbose, but also more accurate. saying "local source"
could refer to any ref in the local refstore, including something in
refs/remotes/*. A later change will teach guess_ref() to infer a ref
type from remote-tracking refs, so let's not confuse the two.

While I'm at it, add a "TRANSLATORS" comment since the message has
gotten more complex and it's not as clear what the two %s's refer to.

1. https://public-inbox.org/git/20181010205505.GB12949@sigill.intra.peff.net/
2. https://public-inbox.org/git/xmqqbm81lb7c.fsf@gitster-ct.c.googlers.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

i18n: remote.c: mark error(...) messages for translationÆvar Arnfjörð Bjarmason Tue, 13 Nov 2018 19:52:40 +0000 (19:52 +0000)

i18n: remote.c: mark error(...) messages for translation

Mark up the error(...) messages in remote.c for translation. The likes
of "unable to push to unqualified destination" are relatively big
parts of the UI, i.e. error messages shown when "git push" fails.

I don't think any of these are plumbing, an the entire test suite
passes when running the tests with GIT_GETTEXT_POISON=1 (after
building with GETTEXT_POISON).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

remote.c: add braces in anticipation of a follow-up... Ævar Arnfjörð Bjarmason Tue, 13 Nov 2018 19:52:39 +0000 (19:52 +0000)

remote.c: add braces in anticipation of a follow-up change

The CodingGuidelines say "When there are multiple arms to a
conditional and some of them require braces, enclose even a single
line block in braces for consistency.". Fix the code in
match_explicit() to conform.

While I'm at it change the if/else if/else in guess_ref() to use
braces. This is not currently needed, but a follow-up change will add
a new multi-line condition to that logic.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

range-diff: make diff option behavior (e.g. --stat... Ævar Arnfjörð Bjarmason Tue, 13 Nov 2018 18:55:58 +0000 (18:55 +0000)

range-diff: make diff option behavior (e.g. --stat) consistent

Make the behavior when diff options (e.g. "--stat") are passed
consistent with how "diff" behaves.

Before 73a834e9e2 ("range-diff: relieve callers of low-level
configuration burden", 2018-07-22) running range-diff with "--stat"
would produce stat output and the diff output, as opposed to how
"diff" behaves where once "--stat" is specified "--patch" also needs
to be provided to emit the patch output.

As noted in a previous change ("range-diff doc: add a section about
output stability", 2018-11-07) the "--stat" output with "range-diff"
is useless at the moment.

But we should behave consistently with "diff" in anticipation of such
output being useful in the future, because it would make for confusing
UI if "diff" and "range-diff" behaved differently when it came to how
they interpret diff options.

The new behavior is also consistent with the existing documentation
added in ba931edd28 ("range-diff: populate the man page",
2018-08-13). See "[...]also accepts the regular diff options[...]" in
git-range-diff(1).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

win32: replace pthread_cond_*() with much simpler codeLoo Rong Jie Tue, 13 Nov 2018 18:52:35 +0000 (10:52 -0800)

win32: replace pthread_cond_*() with much simpler code

The Win32 CONDITION_VARIABLE has better performance and is easier to
maintain, as the code is a lot shorter now (the semantics of the
CONDITION_VARIABLE matches the pthread_cond_t very well).

Note: CONDITION_VARIABLE is not available in Windows XP and below,
but the declared minimal Windows version required to build and run
Git for Windows is Windows Vista (which is also beyond its
end-of-life, but for less long than Windows XP), so that's okay.

Signed-off-by: Loo Rong Jie <loorongjie@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

checkout: print something when checking out pathsNguyễn Thái Ngọc Duy Tue, 13 Nov 2018 18:28:00 +0000 (19:28 +0100)

checkout: print something when checking out paths

One of the problems with "git checkout" is that it does so many
different things and could confuse people specially when we fail to
handle ambiguation correctly.

One way to help with that is tell the user what sort of operation is
actually carried out. When switching branches, we always print
something unless --quiet, either

- "HEAD is now at ..."
- "Reset branch ..."
- "Already on ..."
- "Switched to and reset ..."
- "Switched to a new branch ..."
- "Switched to branch ..."

Checking out paths however is silent. Print something so that if we
got the user intention wrong, they won't waste too much time to find
that out. For the remaining cases of checkout we now print either

- "Checked out ... paths out of the index"
- "Checked out ... paths out of <abbrev hash>"

Since the purpose of printing this is to help disambiguate. Only do it
when "--" is missing.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

checkout: disambiguate dwim tracking branches and local... Nguyễn Thái Ngọc Duy Tue, 13 Nov 2018 17:52:26 +0000 (18:52 +0100)

checkout: disambiguate dwim tracking branches and local files

When checkout dwim is added in [1], it is restricted to only dwim when
certain conditions are met and fall back to default checkout behavior
otherwise. It turns out falling back could be confusing. One of the
conditions to turn

git checkout frotz

to

git checkout -b frotz origin/frotz

is that frotz must not exist as a file. But when the user comes to
expect "git checkout frotz" to create the branch "frotz" and there
happens to be a file named "frotz", git's silently reverting "frotz"
file content is not helping. This is reported in Git mailing list [2]
and even used as an example of "Git is bad" elsewhere [3].

We normally try to do the right thing, but when there are multiple
"right things" to do, it's best to leave it to the user to decide.
Check this case, ask the user to to disambiguate:

- "git checkout -- foo" will check out path "foo"
- "git checkout foo --" will dwim and create branch "foo" [4]

For users who do not want dwim, use --no-guess. It's useless in this
particular case because "git checkout --no-guess foo --" will just
fail. But it could be used by scripts.

[1] 70c9ac2f19 (DWIM "git checkout frotz" to "git checkout -b frotz
origin/frotz" - 2009-10-18)
[2] https://public-inbox.org/git/CACsJy8B2TVr1g+k+eSQ=pBEO3WN4_LtgLo9gpur8X7Z9GOFL_A@mail.gmail.com/
[3] https://news.ycombinator.com/item?id=18230655
[4] a047fafc78 (checkout: allow dwim for branch creation for "git
checkout $branch --" - 2013-10-18)

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

mingw: use `CreateHardLink()` directlyJohannes Schindelin Tue, 13 Nov 2018 14:37:02 +0000 (06:37 -0800)

mingw: use `CreateHardLink()` directly

The function `CreateHardLink()` is available in all supported Windows
versions (even since Windows XP), so there is no more need to resolve it
at runtime.

Helped-by: Max Kirillov <max@max630.net>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/lib-gettext: test installed git-sh-i18n if GIT_TEST_I... Johannes Schindelin Mon, 12 Nov 2018 13:48:36 +0000 (05:48 -0800)

t/lib-gettext: test installed git-sh-i18n if GIT_TEST_INSTALLED is set

It makes very, very little sense to test the built git-sh-i18n when the
user asked specifically to test another one.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

tests: respect GIT_TEST_INSTALLED when initializing... Johannes Schindelin Mon, 12 Nov 2018 13:48:34 +0000 (05:48 -0800)

tests: respect GIT_TEST_INSTALLED when initializing repositories

It really makes very, very little sense to use a different git
executable than the one the caller indicated via setting the environment
variable GIT_TEST_INSTALLED.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

tests: fix GIT_TEST_INSTALLED's PATH to include t/helper/Johannes Schindelin Mon, 12 Nov 2018 13:48:33 +0000 (05:48 -0800)

tests: fix GIT_TEST_INSTALLED's PATH to include t/helper/

We really need to be able to find the test helpers... Really. This
change was forgotten when we moved the test helpers into t/helper/

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

coccicheck: introduce 'pending' semantic patchesSZEDER Gábor Sat, 10 Nov 2018 00:10:52 +0000 (16:10 -0800)

coccicheck: introduce 'pending' semantic patches

Teach `make coccicheck` to avoid patches named "*.pending.cocci" and
handle them separately in a new `make coccicheck-pending` instead.
This means that we can separate "critical" patches from "FYI" patches.
The former target can continue causing Travis to fail its static
analysis job, while the latter can let us keep an eye on ongoing
(pending) transitions without them causing too much fallout.

Document the intended use-cases around these two targets.
As the process around the pending patches is not yet fully explored,
leave that out.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Based-on-work-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Tenth batch for 2.20Junio C Hamano Tue, 13 Nov 2018 13:13:52 +0000 (22:13 +0900)

Tenth batch for 2.20

Signed-off-by: Junio C Hamano <gitster@pobox.com>

Merge branch 'nd/complete-format-patch'Junio C Hamano Tue, 13 Nov 2018 13:37:28 +0000 (22:37 +0900)

Merge branch 'nd/complete-format-patch'

The support for format-patch (and send-email) by the command-line
completion script (in contrib/) has been simplified a bit.

* nd/complete-format-patch:
completion: use __gitcomp_builtin for format-patch

Merge branch 'nd/tree-walk-path-exclusion'Junio C Hamano Tue, 13 Nov 2018 13:37:28 +0000 (22:37 +0900)

Merge branch 'nd/tree-walk-path-exclusion'

Pathspec matching against a tree object were buggy when negative
pathspec elements were involved, which has been fixed.

* nd/tree-walk-path-exclusion:
tree-walk.c: fix overoptimistic inclusion in :(exclude) matching

Merge branch 'sg/travis-install-dependencies'Junio C Hamano Tue, 13 Nov 2018 13:37:27 +0000 (22:37 +0900)

Merge branch 'sg/travis-install-dependencies'

The procedure to install dependencies before testing at Travis CI
is getting revamped for both simplicity and flexibility, taking
advantage of the recent move to the vm-based environment.

* sg/travis-install-dependencies:
travis-ci: install packages in 'ci/install-dependencies.sh'

Merge branch 'bp/add-diff-files-optim'Junio C Hamano Tue, 13 Nov 2018 13:37:27 +0000 (22:37 +0900)

Merge branch 'bp/add-diff-files-optim'

"git add" needs to internally run "diff-files" equivalent, and the
codepath learned the same optimization as "diff-files" has to run
lstat(2) in parallel to find which paths have been updated in the
working tree.

* bp/add-diff-files-optim:
add: speed up cmd_add() by utilizing read_cache_preload()

Merge branch 'jk/xdiff-interface'Junio C Hamano Tue, 13 Nov 2018 13:37:27 +0000 (22:37 +0900)

Merge branch 'jk/xdiff-interface'

The interface into "xdiff" library used to discover the offset and
size of a generated patch hunk by first formatting it into the
textual hunk header "@@ -n,m +k,l @@" and then parsing the numbers
out. A new interface has been introduced to allow callers a more
direct access to them.

* jk/xdiff-interface:
xdiff-interface: drop parse_hunk_header()
range-diff: use a hunk callback
diff: convert --check to use a hunk callback
combine-diff: use an xdiff hunk callback
diff: use hunk callback for word-diff
diff: discard hunk headers for patch-ids earlier
diff: avoid generating unused hunk header lines
xdiff-interface: provide a separate consume callback for hunks
xdiff: provide a separate emit callback for hunks

Merge branch 'jk/misc-unused-fixes'Junio C Hamano Tue, 13 Nov 2018 13:37:26 +0000 (22:37 +0900)

Merge branch 'jk/misc-unused-fixes'

Assorted fixes for bugs found while auditing -Wunused-parameter
warnings.

* jk/misc-unused-fixes:
approxidate: fix NULL dereference in date_time()
pathspec: handle non-terminated strings with :(attr)
approxidate: handle pending number for "specials"
rev-list: handle flags for --indexed-objects

Merge branch 'nd/per-worktree-ref-iteration'Junio C Hamano Tue, 13 Nov 2018 13:37:26 +0000 (22:37 +0900)

Merge branch 'nd/per-worktree-ref-iteration'

The code to traverse objects for reachability, used to decide what
objects are unreferenced and expendable, have been taught to also
consider per-worktree refs of other worktrees as starting points to
prevent data loss.

* nd/per-worktree-ref-iteration:
git-worktree.txt: correct linkgit command name
reflog expire: cover reflog from all worktrees
fsck: check HEAD and reflog from other worktrees
fsck: move fsck_head_link() to get_default_heads() to avoid some globals
revision.c: better error reporting on ref from different worktrees
revision.c: correct a parameter name
refs: new ref types to make per-worktree refs visible to all worktrees
Add a place for (not) sharing stuff between worktrees
refs.c: indent with tabs, not spaces

Merge branch 'bp/refresh-index-using-preload'Junio C Hamano Tue, 13 Nov 2018 13:37:25 +0000 (22:37 +0900)

Merge branch 'bp/refresh-index-using-preload'

The helper function to refresh the cached stat information in the
in-core index has learned to perform the lstat() part of the
operation in parallel on multi-core platforms.

* bp/refresh-index-using-preload:
refresh_index: remove unnecessary calls to preload_index()
speed up refresh_index() by utilizing preload_index()

Merge branch 'ag/rebase-i-in-c'Junio C Hamano Tue, 13 Nov 2018 13:37:25 +0000 (22:37 +0900)

Merge branch 'ag/rebase-i-in-c'

Code clean-up for a topic already in 'master'.

* ag/rebase-i-in-c:
sequencer.c: remove a stray semicolon

Merge branch 'al/send-email-auto-cte-fixup'Junio C Hamano Tue, 13 Nov 2018 13:37:25 +0000 (22:37 +0900)

Merge branch 'al/send-email-auto-cte-fixup'

"git send-email --transfer-encoding=..." in recent versions of Git
sometimes produced an empty "Content-Transfer-Encoding:" header,
which has been corrected.

* al/send-email-auto-cte-fixup:
send-email: avoid empty transfer encoding header

Merge branch 'ds/add-missing-tags'Junio C Hamano Tue, 13 Nov 2018 13:37:24 +0000 (22:37 +0900)

Merge branch 'ds/add-missing-tags'

The history traversal used to implement the tag-following has been
optimized by introducing a new helper.

* ds/add-missing-tags:
remote: make add_missing_tags() linear
test-reach: test get_reachable_subset
commit-reach: implement get_reachable_subset

Merge branch 'sh/mingw-safer-compat-poll'Junio C Hamano Tue, 13 Nov 2018 13:37:24 +0000 (22:37 +0900)

Merge branch 'sh/mingw-safer-compat-poll'

Windows fix.

* sh/mingw-safer-compat-poll:
poll: use GetTickCount64() to avoid wrap-around issues

Merge branch 'js/rebase-p-tests'Junio C Hamano Tue, 13 Nov 2018 13:37:24 +0000 (22:37 +0900)

Merge branch 'js/rebase-p-tests'

In preparation to the day when we can deprecate and remove the
"rebase -p", make sure we can skip and later remove tests for
it.

* js/rebase-p-tests:
tests: optionally skip `git rebase -p` tests
t3418: decouple test cases from a previous `rebase -p` test case
t3404: decouple some test cases from outcomes of previous test cases

Merge branch 'pw/am-rebase-read-author-script'Junio C Hamano Tue, 13 Nov 2018 13:37:23 +0000 (22:37 +0900)

Merge branch 'pw/am-rebase-read-author-script'

Unify code to read the author-script used in "git am" and the
commands that use the sequencer machinery, e.g. "git rebase -i".

* pw/am-rebase-read-author-script:
sequencer: use read_author_script()
add read_author_script() to libgit
am: rename read_author_script()
am: improve author-script error reporting
am: don't die in read_author_script()

Merge branch 'jc/war-on-string-list'Junio C Hamano Tue, 13 Nov 2018 13:37:23 +0000 (22:37 +0900)

Merge branch 'jc/war-on-string-list'

Replace three string-list instances used as look-up tables in "git
fetch" with hashmaps.

* jc/war-on-string-list:
fetch: replace string-list used as a look-up table with a hashmap

Merge branch 'ag/rev-parse-all-exclude-fix'Junio C Hamano Tue, 13 Nov 2018 13:37:23 +0000 (22:37 +0900)

Merge branch 'ag/rev-parse-all-exclude-fix'

"git rev-parse --exclude=* --branches --branches" (i.e. first
saying "add only things that do not match '*' out of all branches"
and then adding all branches, without any exclusion this time")
worked as expected, but "--exclude=* --all --all" did not work the
same way, which has been fixed.

* ag/rev-parse-all-exclude-fix:
rev-parse: clear --exclude list after 'git rev-parse --all'

Merge branch 'jt/tighten-fetch-proto-v2-response'Junio C Hamano Tue, 13 Nov 2018 13:37:22 +0000 (22:37 +0900)

Merge branch 'jt/tighten-fetch-proto-v2-response'

"git fetch" was a bit loose in parsing resposes from the other side
when talking over the protocol v2.

* jt/tighten-fetch-proto-v2-response:
fetch-pack: be more precise in parsing v2 response

Merge branch 'ao/submodule-wo-gitmodules-checked-out'Junio C Hamano Tue, 13 Nov 2018 13:37:22 +0000 (22:37 +0900)

Merge branch 'ao/submodule-wo-gitmodules-checked-out'

The submodule support has been updated to read from the blob at
HEAD:.gitmodules when the .gitmodules file is missing from the
working tree.

* ao/submodule-wo-gitmodules-checked-out:
t/helper: add test-submodule-nested-repo-config
submodule: support reading .gitmodules when it's not in the working tree
submodule: add a helper to check if it is safe to write to .gitmodules
t7506: clean up .gitmodules properly before setting up new scenario
submodule: use the 'submodule--helper config' command
submodule--helper: add a new 'config' subcommand
t7411: be nicer to future tests and really clean things up
t7411: merge tests 5 and 6
submodule: factor out a config_set_in_gitmodules_file_gently function
submodule: add a print_config_from_gitmodules() helper

Merge branch 'nb/worktree-api-doc'Junio C Hamano Tue, 13 Nov 2018 13:37:21 +0000 (22:37 +0900)

Merge branch 'nb/worktree-api-doc'

Code readability fix.

* nb/worktree-api-doc:
worktree: rename is_worktree_locked to worktree_lock_reason
worktree: update documentation for lock_reason and lock_reason_valid

Merge branch 'ma/sequencer-do-reset-saner-loop-termination'Junio C Hamano Tue, 13 Nov 2018 13:37:21 +0000 (22:37 +0900)

Merge branch 'ma/sequencer-do-reset-saner-loop-termination'

Code readability fix.

* ma/sequencer-do-reset-saner-loop-termination:
sequencer: break out of loop explicitly

Merge branch 'js/mingw-utf8-env'Junio C Hamano Tue, 13 Nov 2018 13:37:21 +0000 (22:37 +0900)

Merge branch 'js/mingw-utf8-env'

Windows fix.

* js/mingw-utf8-env:
mingw: reencode environment variables on the fly (UTF-16 <-> UTF-8)
t7800: fix quoting

Merge branch 'js/mingw-perl5lib'Junio C Hamano Tue, 13 Nov 2018 13:37:20 +0000 (22:37 +0900)

Merge branch 'js/mingw-perl5lib'

Windows fix.

* js/mingw-perl5lib:
mingw: unset PERL5LIB by default
config: move Windows-specific config settings into compat/mingw.c
config: allow for platform-specific core.* config settings
config: rename `dummy` parameter to `cb` in git_default_config()

Merge branch 'js/mingw-isatty-and-dup2'Junio C Hamano Tue, 13 Nov 2018 13:37:20 +0000 (22:37 +0900)

Merge branch 'js/mingw-isatty-and-dup2'

Windows fix.

* js/mingw-isatty-and-dup2:
mingw: fix isatty() after dup2()

Merge branch 'ab/pack-tests-cleanup'Junio C Hamano Tue, 13 Nov 2018 13:37:20 +0000 (22:37 +0900)

Merge branch 'ab/pack-tests-cleanup'

A couple of tests used to leave the repository in a state that is
deliberately corrupt, which have been corrected.

* ab/pack-tests-cleanup:
index-pack tests: don't leave test repo dirty at end
pack-objects tests: don't leave test .git corrupt at end
pack-objects test: modernize style

Merge branch 'ds/test-multi-pack-index'Junio C Hamano Tue, 13 Nov 2018 13:37:19 +0000 (22:37 +0900)

Merge branch 'ds/test-multi-pack-index'

Tests for the recently introduced multi-pack index machinery.

* ds/test-multi-pack-index:
packfile: close multi-pack-index in close_all_packs
multi-pack-index: define GIT_TEST_MULTI_PACK_INDEX
midx: close multi-pack-index on repack
midx: fix broken free() in close_midx()

Merge branch 'nd/wildmatch-double-asterisk'Junio C Hamano Tue, 13 Nov 2018 13:37:19 +0000 (22:37 +0900)

Merge branch 'nd/wildmatch-double-asterisk'

A pattern with '**' that does not have a slash on either side used
to be an invalid one, but the code now treats such double-asterisks
the same way as two normal asterisks that happen to be adjacent to
each other.

* nd/wildmatch-double-asterisk:
wildmatch: change behavior of "foo**bar" in WM_PATHNAME mode

Merge branch 'nd/per-worktree-config'Junio C Hamano Tue, 13 Nov 2018 13:37:18 +0000 (22:37 +0900)

Merge branch 'nd/per-worktree-config'

A fourth class of configuration files (in addition to the
traditional "system wide", "per user in the $HOME directory" and
"per repository in the $GIT_DIR/config") has been introduced so
that different worktrees that share the same repository (hence the
same $GIT_DIR/config file) can use different customization.

* nd/per-worktree-config:
worktree: add per-worktree config files
t1300: extract and use test_cmp_config()

Merge branch 'jk/stream-pack-non-delta-clarification'Junio C Hamano Tue, 13 Nov 2018 13:37:18 +0000 (22:37 +0900)

Merge branch 'jk/stream-pack-non-delta-clarification'

Additional comment on a tricky piece of code to help developers.

* jk/stream-pack-non-delta-clarification:
read_istream_pack_non_delta(): document input handling

Merge branch 'jk/proto-v2-ref-prefix-fix'Junio C Hamano Tue, 13 Nov 2018 13:37:17 +0000 (22:37 +0900)

Merge branch 'jk/proto-v2-ref-prefix-fix'

"git ls-remote $there foo" was broken by recent update for the
protocol v2 and stopped showing refs that match 'foo' that are not
refs/{heads,tags}/foo, which has been fixed.

* jk/proto-v2-ref-prefix-fix:
ls-remote: pass heads/tags prefixes to transport
ls-remote: do not send ref prefixes for patterns

Merge branch 'jk/detect-truncated-zlib-input'Junio C Hamano Tue, 13 Nov 2018 13:37:17 +0000 (22:37 +0900)

Merge branch 'jk/detect-truncated-zlib-input'

A regression in Git 2.12 era made "git fsck" fall into an infinite
loop while processing truncated loose objects.

* jk/detect-truncated-zlib-input:
cat-file: handle streaming failures consistently
check_stream_sha1(): handle input underflow
t1450: check large blob in trailing-garbage test

Merge branch 'nd/config-split'Junio C Hamano Tue, 13 Nov 2018 13:37:16 +0000 (22:37 +0900)

Merge branch 'nd/config-split'

Split the overly large Documentation/config.txt file into million
little pieces. This potentially allows each individual piece
included into the manual page of the command it affects more easily.

* nd/config-split: (81 commits)
config.txt: remove config/dummy.txt
config.txt: move worktree.* to a separate file
config.txt: move web.* to a separate file
config.txt: move versionsort.* to a separate file
config.txt: move user.* to a separate file
config.txt: move url.* to a separate file
config.txt: move uploadpack.* to a separate file
config.txt: move uploadarchive.* to a separate file
config.txt: move transfer.* to a separate file
config.txt: move tag.* to a separate file
config.txt: move submodule.* to a separate file
config.txt: move stash.* to a separate file
config.txt: move status.* to a separate file
config.txt: move splitIndex.* to a separate file
config.txt: move showBranch.* to a separate file
config.txt: move sequencer.* to a separate file
config.txt: move sendemail-config.txt to config/
config.txt: move reset.* to a separate file
config.txt: move rerere.* to a separate file
config.txt: move repack.* to a separate file
...

format-patch: respect --stat in cover letter's diffstatNguyễn Thái Ngọc Duy Sat, 10 Nov 2018 05:46:24 +0000 (06:46 +0100)

format-patch: respect --stat in cover letter's diffstat

Commit 43662b23ab (format-patch: keep cover-letter diffstat wrapped in
72 columns - 2018-01-24) uncondtionally sets stat width to 72 when
generating diffstat for the cover letter, ignoring --stat from command
line. But it should only do so when stat width is still default
(i.e. stat_width == 0).

In order to fix this, we should only set stat_width if stat_width is
zero. But it will never be. Commit 071dd0ba43 (format-patch: reduce
patch diffstat width to 72 - 2018-02-01) makes sure that default stat
width will be 72 (ignoring $COLUMNS, but could still be overriden by
--stat). So all we need to do here is drop the assignment.

Reported-by: Laszlo Ersek <lersek@redhat.com>
Helped-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

built-in rebase: reinstate `checkout -q` behavior where... Johannes Schindelin Mon, 12 Nov 2018 11:44:32 +0000 (03:44 -0800)

built-in rebase: reinstate `checkout -q` behavior where appropriate

When we converted a `git checkout -q $onto^0` call to use
`reset_head()`, we inadvertently incurred a change from a twoway_merge
to a oneway_merge, as if we wanted a `git reset --hard` instead.

This has performance ramifications under certain, though, as the
oneway_merge needs to lstat() every single index entry whereas
twoway_merge does not.

So let's go back to the old behavior.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

rebase: prepare reset_head() for more flagsJohannes Schindelin Mon, 12 Nov 2018 11:44:31 +0000 (03:44 -0800)

rebase: prepare reset_head() for more flags

Currently, we only accept the flag indicating whether the HEAD should be
detached not. In the next commit, we want to introduce another flag: to
toggle between emulating `reset --hard` vs `checkout -q`.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

rebase: consolidate clean-up code before leaving reset_... Johannes Schindelin Mon, 12 Nov 2018 11:44:30 +0000 (03:44 -0800)

rebase: consolidate clean-up code before leaving reset_head()

The same clean-up code is repeated quite a few times; Let's DRY up the
code some.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

refs: fix some exclude patterns being ignoredRafael Ascensão Mon, 12 Nov 2018 13:25:44 +0000 (13:25 +0000)

refs: fix some exclude patterns being ignored

`--exclude` from rev-list and rev-parse fails to exclude references if
the next `--branches`, `--tags` or `--remotes` use the optional
inclusive glob because those options are implemented as particular cases
of `--glob=`, which itself requires that exclude patterns begin with
'refs/'.

But it makes sense for `--branches=glob` and friends to be aware that
exclusions patterns for them shouldn't be 'refs/<type>/' prefixed, the
same way exclude patterns for `--branches` and friends (without the
optional glob) already are.

Let's record in 'refs.c:struct ref_filter' which context the exclude
pattern is tied to, so refs.c:filter_refs() can decide if it should
ignore the prefix when trying to match.

Signed-off-by: Rafael Ascensão <rafa.almas@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

refs: show --exclude failure with --branches/tags/remot... Rafael Ascensão Mon, 12 Nov 2018 13:25:43 +0000 (13:25 +0000)

refs: show --exclude failure with --branches/tags/remotes=glob

The documentation of `--exclude=` option from rev-list and rev-parse
explicitly states that exclude patterns *should not* start with 'refs/'
when used with `--branches`, `--tags` or `--remotes`.

However, following this advice results in refereces not being excluded
if the next `--branches`, `--tags`, `--remotes` use the optional
inclusive glob.

Demonstrate this failure.

Signed-off-by: Rafael Ascensão <rafa.almas@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

fetch-pack: drop custom loose object cacheJeff King Mon, 12 Nov 2018 14:55:58 +0000 (09:55 -0500)

fetch-pack: drop custom loose object cache

Commit 024aa4696c (fetch-pack.c: use oidset to check existence of loose
object, 2018-03-14) added a cache to avoid calling stat() for a bunch of
loose objects we don't have.

Now that OBJECT_INFO_QUICK handles this caching itself, we can drop the
custom solution.

Note that this might perform slightly differently, as the original code
stopped calling readdir() when we saw more loose objects than there were
refs. So:

1. The old code might have spent work on readdir() to fill the cache,
but then decided there were too many loose objects, wasting that
effort.

2. The new code might spend a lot of time on readdir() if you have a
lot of loose objects, even though there are very few objects to
ask about.

In practice it probably won't matter either way; see the previous commit
for some discussion of the tradeoff.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

sha1-file: use loose object cache for quick existence... Jeff King Mon, 12 Nov 2018 14:54:42 +0000 (09:54 -0500)

sha1-file: use loose object cache for quick existence check

In cases where we expect to ask has_sha1_file() about a lot of objects
that we are not likely to have (e.g., during fetch negotiation), we
already use OBJECT_INFO_QUICK to sacrifice accuracy (due to racing with
a simultaneous write or repack) for speed (we avoid re-scanning the pack
directory).

However, even checking for loose objects can be expensive, as we will
stat() each one. On many systems this cost isn't too noticeable, but
stat() can be particularly slow on some operating systems, or due to
network filesystems.

Since the QUICK flag already tells us that we're OK with a slightly
stale answer, we can use that as a cue to look in our in-memory cache of
each object directory. That basically trades an in-memory binary search
for a stat() call.

Note that it is possible for this to actually be _slower_. We'll do a
full readdir() to fill the cache, so if you have a very large number of
loose objects and a very small number of lookups, that readdir() may end
up more expensive.

This shouldn't be a big deal in practice. If you have a large number of
reachable loose objects, you'll already run into performance problems
(which you should remedy by repacking). You may have unreachable objects
which wouldn't otherwise impact performance. Usually these would go away
with the prune step of "git gc", but they may be held for up to 2 weeks
in the default configuration.

So it comes down to how many such objects you might reasonably expect to
have, how much slower is readdir() on N entries versus M stat() calls
(and here we really care about the syscall backing readdir(), like
getdents() on Linux, but I'll just call this readdir() below).

If N is much smaller than M (a typical packed repo), we know this is a
big win (few readdirs() followed by many uses of the resulting cache).
When N and M are similar in size, it's also a win. We care about the
latency of making a syscall, and readdir() should be giving us many
values in a single call. How many?

On Linux, running "strace -e getdents ls" shows a 32k buffer getting 512
entries per call (which is 64 bytes per entry; the name itself is 38
bytes, plus there are some other fields). So we can imagine that this is
always a win as long as the number of loose objects in the repository is
a factor of 500 less than the number of lookups you make. It's hard to
auto-tune this because we don't generally know up front how many lookups
we're going to do. But it's unlikely for this to perform significantly
worse.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

object-store: provide helpers for loose_objects_cacheJeff King Mon, 12 Nov 2018 14:50:56 +0000 (09:50 -0500)

object-store: provide helpers for loose_objects_cache

Our object_directory struct has a loose objects cache that all users of
the struct can see. But the only one that knows how to load the cache is
find_short_object_filename(). Let's extract that logic in to a reusable
function.

While we're at it, let's also reset the cache when we re-read the object
directories. This shouldn't have an impact on performance, as re-reads
are meant to be rare (and are already expensive, so we avoid them with
things like OBJECT_INFO_QUICK).

Since the cache is already meant to be an approximation, it's tempting
to skip even this bit of safety. But it's necessary to allow more code
to use it. For instance, fetch-pack explicitly re-reads the object
directory after performing its fetch, and would be confused if we didn't
clear the cache.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

sha1-file: use an object_directory for the main object dirJeff King Mon, 12 Nov 2018 14:50:39 +0000 (09:50 -0500)

sha1-file: use an object_directory for the main object dir

Our handling of alternate object directories is needlessly different
from the main object directory. As a result, many places in the code
basically look like this:

do_something(r->objects->objdir);

for (odb = r->objects->alt_odb_list; odb; odb = odb->next)
do_something(odb->path);

That gets annoying when do_something() is non-trivial, and we've
resorted to gross hacks like creating fake alternates (see
find_short_object_filename()).

Instead, let's give each raw_object_store a unified list of
object_directory structs. The first will be the main store, and
everything after is an alternate. Very few callers even care about the
distinction, and can just loop over the whole list (and those who care
can just treat the first element differently).

A few observations:

- we don't need r->objects->objectdir anymore, and can just
mechanically convert that to r->objects->odb->path

- object_directory's path field needs to become a real pointer rather
than a FLEX_ARRAY, in order to fill it with expand_base_dir()

- we'll call prepare_alt_odb() earlier in many functions (i.e.,
outside of the loop). This may result in us calling it even when our
function would be satisfied looking only at the main odb.

But this doesn't matter in practice. It's not a very expensive
operation in the first place, and in the majority of cases it will
be a noop. We call it already (and cache its results) in
prepare_packed_git(), and we'll generally check packs before loose
objects. So essentially every program is going to call it
immediately once per program.

Arguably we should just prepare_alt_odb() immediately upon setting
up the repository's object directory, which would save us sprinkling
calls throughout the code base (and forgetting to do so has been a
source of subtle bugs in the past). But I've stopped short of that
here, since there are already a lot of other moving parts in this
patch.

- Most call sites just get shorter. The check_and_freshen() functions
are an exception, because they have entry points to handle local and
nonlocal directories separately.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

handle alternates paths the same as the main object dirJeff King Mon, 12 Nov 2018 14:49:35 +0000 (09:49 -0500)

handle alternates paths the same as the main object dir

When we generate loose file paths for the main object directory, the
caller provides a buffer to loose_object_path (formerly sha1_file_name).
The callers generally keep their own static buffer to avoid excessive
reallocations.

But for alternate directories, each struct carries its own scratch
buffer. This is needlessly different; let's unify them.

We could go either direction here, but this patch moves the alternates
struct over to the main directory style (rather than vice-versa).
Technically the alternates style is more efficient, as it avoids
rewriting the object directory name on each call. But this is unlikely
to matter in practice, as we avoid reallocations either way (and nobody
has ever noticed or complained that the main object directory is copying
a few extra bytes before making a much more expensive system call).

And this has the advantage that the reusable buffers are tied to
particular calls, which makes the invalidation rules simpler (for
example, the return value from stat_sha1_file() used to be invalidated
by basically any other object call, but now it is affected only by other
calls to stat_sha1_file()).

We do steal the trick from alt_sha1_path() of returning a pointer to the
filled buffer, which makes a few conversions more convenient.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

sha1_file_name(): overwrite buffer instead of appendingJeff King Mon, 12 Nov 2018 14:48:56 +0000 (09:48 -0500)

sha1_file_name(): overwrite buffer instead of appending

The sha1_file_name() function is used to generate the path to a loose
object in the object directory. It doesn't make much sense for it to
append, since the the path we write may be absolute (i.e., you cannot
reliably build up a path with it). Because many callers use it with a
static buffer, they have to strbuf_reset() manually before each call
(and the other callers always use an empty buffer, so they don't care
either way). Let's handle this automatically.

Since we're changing the semantics, let's take the opportunity to give
it a more hash-neutral name (which will also catch any callers from
topics in flight).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

rename "alternate_object_database" to "object_directory"Jeff King Mon, 12 Nov 2018 14:48:47 +0000 (09:48 -0500)

rename "alternate_object_database" to "object_directory"

In preparation for unifying the handling of alt odb's and the normal
repo object directory, let's use a more neutral name. This patch is
purely mechanical, swapping the type name, and converting any variables
named "alt" to "odb". There should be no functional change, but it will
reduce the noise in subsequent diffs.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

submodule--helper: prefer strip_suffix() to ends_with()Jeff King Mon, 12 Nov 2018 14:47:04 +0000 (09:47 -0500)

submodule--helper: prefer strip_suffix() to ends_with()

Using strip_suffix() lets us avoid repeating ourselves. It also makes
the handling of "/" a bit less subtle (we strip one less character than
we matched in order to leave it in place, but we can just as easily
include the "/" when we add more path components).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

fsck: do not reuse child_process structsJeff King Mon, 12 Nov 2018 14:46:54 +0000 (09:46 -0500)

fsck: do not reuse child_process structs

The run-command API makes no promises about what is left in a struct
child_process after a command finishes, and it's not safe to simply
reuse it again for a similar command. In particular:

- if you use child->args or child->env_array, they are cleared after
finish_command()

- likewise, start_command() may point child->argv at child->args->argv;
reusing that would lead to accessing freed memory

- the in/out/err may hold pipe descriptors from the previous run

These two calls are _probably_ OK because they do not use any of those
features. But it's only by chance, and may break in the future; let's
reinitialize our struct for each program we run.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

apply --recount: allow "no-op hunks"Johannes Schindelin Mon, 12 Nov 2018 20:54:49 +0000 (12:54 -0800)

apply --recount: allow "no-op hunks"

When editing patches e.g. in `git add -e`, it is quite common that a
hunk ends up having no -/+ lines, i.e. it is now supposed to do nothing.

This use case was broken by ad6e8ed37bc1 (apply: reject a hunk that does
not do anything, 2015-06-01) with the good intention of catching a very
real, different issue in hand-edited patches.

So let's use the `--recount` option as the tell-tale whether the user
would actually be okay with no-op hunks.

Add a test case to make sure that this use case does not regress again.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Reviewed-by: Josh Steadmon <steadmon@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

status: rebase and merge can be in progress at the... Johannes Schindelin Mon, 12 Nov 2018 23:26:02 +0000 (15:26 -0800)

status: rebase and merge can be in progress at the same time

Since `git rebase -r` was introduced, that is possible. But our
machinery did not think that possible, and failed to say anything about
the rebase in progress when in the middle of a merge.

Let's work around that in the minimal fashion.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

built-in rebase --skip/--abort: clean up stale .git... Johannes Schindelin Mon, 12 Nov 2018 23:26:01 +0000 (15:26 -0800)

built-in rebase --skip/--abort: clean up stale .git/<name> files

The scripted version of the rebase used to execute `git reset --hard`
when skipping or aborting. When we ported this to C, we did update the
worktree and some reflogs, but we failed to imitate `git reset --hard`'s
behavior regarding files in .git/ such as MERGE_HEAD.

Let's address this oversight.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

rebase -i: include MERGE_HEAD into files to clean upJohannes Schindelin Mon, 12 Nov 2018 23:25:59 +0000 (15:25 -0800)

rebase -i: include MERGE_HEAD into files to clean up

Every once in a while, the interactive rebase makes sure that no stale
files are lying around. These days, we need to include MERGE_HEAD into
that set of files, as the `merge` command will generate them.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

rebase -r: do not write MERGE_HEAD unless neededJohannes Schindelin Mon, 12 Nov 2018 23:25:58 +0000 (15:25 -0800)

rebase -r: do not write MERGE_HEAD unless needed

When we detect that a `merge` can be skipped because the merged commit
is already an ancestor of HEAD, we do not need to commit, therefore
writing the MERGE_HEAD file is useless.

It is actually worse than useless: a subsequent `git commit` will pick
it up and think that we want to merge that commit, still.

To avoid that, move the code that writes the MERGE_HEAD file to a
location where we already know that the `merge` cannot be skipped.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

rebase -r: demonstrate bug with conflicting mergesJohannes Schindelin Mon, 12 Nov 2018 23:25:57 +0000 (15:25 -0800)

rebase -r: demonstrate bug with conflicting merges

When calling `merge` on a branch that has already been merged, that
`merge` is skipped quietly, but currently a MERGE_HEAD file is being
left behind and will then be grabbed by the next `pick` (that did
not want to create a *merge* commit).

Demonstrate this.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/notes: remove unnecessary freeCarlo Marcelo Arenas Belón Sun, 11 Nov 2018 09:49:33 +0000 (01:49 -0800)

builtin/notes: remove unnecessary free

511726e4b1 ("builtin/notes: fix premature failure when trying to add
the empty blob", 2014-11-09) removed the check for !len but left a
call to free the buffer that will be otherwise NULL

Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Acked-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

remote-curl.c: xcurl_off_t is not portable (on 32 bit... Torsten Bögershausen Fri, 9 Nov 2018 17:41:10 +0000 (18:41 +0100)

remote-curl.c: xcurl_off_t is not portable (on 32 bit platfoms)

When setting
DEVELOPER = 1
DEVOPTS = extra-all

"gcc (Raspbian 6.3.0-18+rpi1+deb9u1) 6.3.0 20170516" errors out with
"comparison is always false due to limited range of data type"
"[-Werror=type-limits]"

It turns out that the function xcurl_off_t() has 2 flavours:

- It gives a warning 32 bit systems, like Linux
- It takes the signed ssize_t as a paramter, but the only caller is using
a size_t (which is typically unsigned these days)

The original motivation of this function is to make sure that sizes > 2GiB
are handled correctly. The curl documentation says:
"For any given platform/compiler curl_off_t must be typedef'ed to a 64-bit
wide signed integral data type"
On a 32 bit system "size_t" can be promoted into a 64 bit signed value
without loss of data, and therefore we may see the
"comparison is always false" warning.
On a 64 bit system it may happen, at least in theory, that size_t is > 2^63,
and then the promotion from an unsigned "size_t" into a signed "curl_off_t"
may be a problem.

One solution to suppress a possible compiler warning could be to remove
the function xcurl_off_t().

However, to be on the very safe side, we keep it and improve it:

- The len parameter is changed from ssize_t to size_t
- A temporally variable "size" is used, promoted int uintmax_t and the compared
with "maximum_signed_value_of_type(curl_off_t)".
Thanks to Junio C Hamano for this hint.

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Upcast size_t variables to uintmax_t when printingTorsten Bögershausen Sun, 11 Nov 2018 07:05:04 +0000 (08:05 +0100)

Upcast size_t variables to uintmax_t when printing

When printing variables which contain a size, today "unsigned long"
is used at many places.
In order to be able to change the type from "unsigned long" into size_t
some day in the future, we need to have a way to print 64 bit variables
on a system that has "unsigned long" defined to be 32 bit, like Win64.

Upcast all those variables into uintmax_t before they are printed.
This is to prepare for a bigger change, when "unsigned long"
will be converted into size_t for variables which may be > 4Gib.

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

p3400: replace calls to `git checkout -b' by `git check... Alban Gruin Fri, 9 Nov 2018 21:19:23 +0000 (22:19 +0100)

p3400: replace calls to `git checkout -b' by `git checkout -B'

p3400 makes a copy of the current repository to test git-rebase
performance, and creates new branches in the copy with `git checkout
-b'. If the original repository has branches with the same name as the
script is trying to create, this operation will fail.

This replaces these calls by `git checkout -B' to force the creation and
update of these branches.

Signed-off-by: Alban Gruin <alban.gruin@gmail.com>
Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

build: fix broken command-list.h generation with core... Nguyễn Thái Ngọc Duy Sat, 10 Nov 2018 18:23:23 +0000 (19:23 +0100)

build: fix broken command-list.h generation with core.autocrlf

The script generate-cmdlist.sh needs input text files in UNIX line
ending to work correctly. It's been fine even with core.autocrlf set
because Documentation/git-*.txt is forced LF conversion.

But this leaves out gitk.txt and also Documentation/*config.txt that
recently becomes new input for this script. Update the attribute file
to force LF on all *.txt files to be on the safe side.

For more details, please see 00ddc9d13c (Fix build with
core.autocrlf=true - 2017-05-09)

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

rebase-interactive.c: remove the_repository referencesNguyễn Thái Ngọc Duy Sat, 10 Nov 2018 05:49:10 +0000 (06:49 +0100)

rebase-interactive.c: remove the_repository references

While at there add a forward declaration for struct strbuf.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

rerere.c: remove the_repository referencesNguyễn Thái Ngọc Duy Sat, 10 Nov 2018 05:49:09 +0000 (06:49 +0100)

rerere.c: remove the_repository references

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

pack-*.c: remove the_repository referencesNguyễn Thái Ngọc Duy Sat, 10 Nov 2018 05:49:08 +0000 (06:49 +0100)

pack-*.c: remove the_repository references

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

pack-check.c: remove the_repository referencesNguyễn Thái Ngọc Duy Sat, 10 Nov 2018 05:49:07 +0000 (06:49 +0100)

pack-check.c: remove the_repository references

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

notes-cache.c: remove the_repository referencesNguyễn Thái Ngọc Duy Sat, 10 Nov 2018 05:49:06 +0000 (06:49 +0100)

notes-cache.c: remove the_repository references

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

line-log.c: remove the_repository referenceNguyễn Thái Ngọc Duy Sat, 10 Nov 2018 05:49:05 +0000 (06:49 +0100)

line-log.c: remove the_repository reference

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff-lib.c: remove the_repository referencesNguyễn Thái Ngọc Duy Sat, 10 Nov 2018 05:49:04 +0000 (06:49 +0100)

diff-lib.c: remove the_repository references

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>