A small doc update.

* hv/doc-commit-reference-style:
  SubmittingPatches: use gitk's "Copy commit summary" format
  SubmittingPatches: document how to reference previous commits

A small test clean-up for a topic introduced in v2.9.1 and later.

* sg/reflog-past-root:
  t1410: remove superfluous 'git reflog' from the 'walk past root' test

Small code clean-up.

* rs/mailinfo-lib:
  mailinfo: recycle strbuf in check_header()

Small code and comment clean-up.

* jk/tighten-alloc:
  receive-pack: use FLEX_ALLOC_MEM in queue_command()
  correct FLEXPTR_* example in comment

A small code clean-up.

* rs/use-strbuf-add-unique-abbrev:
  use strbuf_add_unique_abbrev() for adding short hashes

A small code clean-up.

* rs/merge-recursive-string-list-init:
  merge-recursive: use STRING_LIST_INIT_NODUP

A small code clean-up.

* rs/merge-add-strategies-simplification:
  merge: use string_list_split() in add_strategies()

Correct an age-old calco (is that a typo-like word for calc)
in the documentation.

* ls/packet-line-protocol-doc-fix:
  pack-protocol: fix maximum pkt-line size

The tempfile (hence its user lockfile) API lets the caller to open
a file descriptor to a temporary file, write into it and then
finalize it by first closing the filehandle and then either
removing or renaming the temporary file.  When the process spawns a
subprocess after obtaining the file descriptor, and if the
subprocess has not exited when the attempt to remove or rename is
made, the last step fails on Windows, because the subprocess has
the file descriptor still open.  Open tempfile with O_CLOEXEC flag
to avoid this (on Windows, this is mapped to O_NOINHERIT).

* bw/mingw-avoid-inheriting-fd-to-lockfile:
  mingw: ensure temporary file handles are not inherited by child processes
  t6026-merge-attr: child processes must not inherit index.lock handles

The "git -c var[=val] cmd" facility to append a configuration
variable definition at the end of the search order was described in
git(1) manual page, but not in git-config(1), which was more likely
place for people to look for when they ask "can I make a one-shot
override, and if so how?"

* dg/document-git-c-in-git-config-doc:
  doc: mention `git -c` in git-config(1)

On Windows, help.browser configuration variable used to be ignored,
which has been corrected.

* js/no-html-bypass-on-windows:
  Revert "display HTML in default browser using Windows' shell API"

"git difftool" by default ignores the error exit from the backend
commands it spawns, because often they signal that they found
differences by exiting with a non-zero status code just like "diff"
does; the exit status codes 126 and above however are special in
that they are used to signal that the command is not executable,
does not exist, or killed by a signal.  "git difftool" has been
taught to notice these exit status codes.

* jk/difftool-command-not-found:
  difftool: always honor fatal error exit codes

"git checkout --detach <branch>" used to give the same advice
message as that is issued when "git checkout <tag>" (or anything
that is not a branch name) is given, but asking with "--detach" is
an explicit enough sign that the user knows what is going on.  The
advice message has been squelched in this case.

* sb/checkout-explit-detach-no-advice:
  checkout: do not mention detach advice for explicit --detach option

When "git merge-recursive" works on history with many criss-cross
merges in "verbose" mode, the names the command assigns to the
virtual merge bases could have overwritten each other by unintended
reuse of the same piece of memory.

* rs/pull-signed-tag:
  commit: use FLEX_ARRAY in struct merge_remote_desc
  merge-recursive: fix verbose output for multiple base trees
  commit: factor out set_merge_remote_desc()
  commit: use xstrdup() in get_merge_parent()

The "t/" hierarchy is prone to get an unusual pathname; "make test"
has been taught to make sure they do not contain paths that cannot
be checked out on Windows (and the mechanism can be reusable to
catch pathnames that are not portable to other platforms as need
arises).

* js/test-lint-pathname:
  t/Makefile: ensure that paths are valid on platforms we care

"git mv dir non-existing-dir/" did not work in some environments
the same way as existing mainstream platforms.  The code now moves
"dir" to "non-existing-dir", without relying on rename("A", "B/")
that strips the trailing slash of '/'.

* js/mv-dir-to-new-directory:
  git mv: do not keep slash in `git mv dir non-existing-dir/`

"import-tars" fast-import script (in contrib/) used to ignore a
hardlink target and replaced it with an empty file, which has been
corrected to record the same blob as the other file the hardlink is
shared with.

* js/import-tars-hardlinks:
  import-tars: support hard links

* ms/document-pack-window-memory-is-per-thread:
  document git-repack interaction of pack.threads and pack.windowMemory

"git push --force-with-lease" already had enough logic to allow
ensuring that such a push results in creation of a ref (i.e. the
receiving end did not have another push from sideways that would be
discarded by our force-pushing), but didn't expose this possibility
to the users.  It does so now.

* jk/push-force-with-lease-creation:
  t5533: make it pass on case-sensitive filesystems
  push: allow pushing new branches with --force-with-lease
  push: add shorthand for --force-with-lease branch creation
  Documentation/git-push: fix placeholder formatting

The reflog output format is documented better, and a new format
--date=unix to report the seconds-since-epoch (without timezone)
has been added.

* jk/reflog-date:
  date: clarify --date=raw description
  date: add "unix" format
  date: document and test "raw-local" mode
  doc/pretty-formats: explain shortening of %gd
  doc/pretty-formats: describe index/time formats for %gd
  doc/rev-list-options: explain "-g" output formats
  doc/rev-list-options: clarify "commit@{Nth}" for "-g" option

"git merge" with renormalization did not work well with
merge-recursive, due to "safer crlf" conversion kicking in when it
shouldn't.

* jc/renormalize-merge-kill-safer-crlf:
  merge: avoid "safer crlf" during recording of merge results
  convert: unify the "auto" handling of CRLF

There are certain house-keeping tasks that need to be performed at
the very beginning of any Git program, and programs that are not
built-in commands had to do them exactly the same way as "git"
potty does.  It was easy to make mistakes in one-off standalone
programs (like test helpers).  A common "main()" function that
calls cmd_main() of individual program has been introduced to
make it harder to make mistakes.

* jk/common-main:
  mingw: declare main()'s argv as const
  common-main: call git_setup_gettext()
  common-main: call restore_sigpipe_to_default()
  common-main: call sanitize_stdfds()
  common-main: call git_extract_argv0_path()
  add an extra level of indirection to main()

According to LARGE_PACKET_MAX in pkt-line.h the maximal length of a
pkt-line packet is 65520 bytes. The pkt-line header takes 4 bytes and
therefore the pkt-line data component must not exceed 65516 bytes.
Signed-off-by: NLars Schneider <larsxschneider@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Update the suggestion in 175d38ca ("SubmittingPatches: document how
to reference previous commits", 2016-07-28) on the format to refer
to a commit to match what gitk has been giving since last year with
its "Copy commit summary" command; also mention this as one of the
ways to obtain a commit reference in this format.
Signed-off-by: NBeat Bolli <dev+git@drbeat.li>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NDavid Glasser <glasser@davidglasser.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

When the index is locked and child processes inherit the handle to
said lock and the parent process wants to remove the lock before the
child process exits, on Windows there is a problem: it won't work
because files cannot be deleted if a process holds a handle on them.
The symptom:

    Rename from 'xxx/.git/index.lock' to 'xxx/.git/index' failed.
    Should I try again? (y/n)

Spawning child processes with bInheritHandles==FALSE would not work
because no file handles would be inherited, not even the hStdXxx
handles in STARTUPINFO (stdin/stdout/stderr).

Opening every file with O_NOINHERIT does not work, either, as e.g.
git-upload-pack expects inherited file handles.

This leaves us with the only way out: creating temp files with the
O_NOINHERIT flag. This flag is Windows-specific, however. For our
purposes, it is equivalent to O_CLOEXEC (which does not exist on
Windows), so let's just open temporary files with the O_CLOEXEC flag and
map that flag to O_NOINHERIT on Windows.

As Eric Wong pointed out, we need to be careful to handle the case where
the Linux headers used to compile Git support O_CLOEXEC but the Linux
kernel used to run Git does not: it returns an EINVAL.

This fixes the test that we just introduced to demonstrate the problem.
Signed-off-by: NBen Wijen <ben@wijen.net>
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since 4804aabc (help (Windows): Display HTML in default browser using
Windows' shell API, 2008-07-13), Git for Windows used to call
`ShellExecute()` to launch the default Windows handler for `.html`
files.

The idea was to avoid going through a shell script, for performance
reasons.

However, this change ignores the `help.browser` config setting. Together
with browsing help not being a performance-critical operation, let's
just revert that patch.
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

On Windows, a file cannot be removed unless all file handles to it have
been released. Hence it is particularly important to close handles when
spawning children (which would probably not even know that they hold on
to those handles).

The example chosen for this test is a custom merge driver that indeed
has no idea that it blocks the deletion of index.lock. The full use case
is a daemon that lives on after the merge, with subsequent invocations
handing off to the daemon, thereby avoiding hefty start-up costs. We
simulate this behavior by simply sleeping one second.

Note that the test only fails on Windows, due to the file locking issue.
Since we have no way to say "expect failure with MINGW, success
otherwise", we simply skip this test on Windows for now.
Signed-off-by: NBen Wijen <ben@wijen.net>
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

To reference previous commits people used to put just the
abbreviated SHA-1 into commit messages.  This is what has evolved as
a more stable format for referencing commits.  So lets document it
for everyone to look-up when needed.
Signed-off-by: NHeiko Voigt <hvoigt@hvoigt.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Some pathnames that are okay on ext4 and on HFS+ cannot be checked
out on Windows. Tests that want to see operations on such paths on
filesystems that support them must do so behind appropriate test
prerequisites, and must not include them in the source tree (instead
they should create them when they run). Otherwise, the source tree
cannot even be checked out.

Make sure that double-quotes, asterisk, colon, greater/less-than,
question-mark, backslash, tab, vertical-bar, as well as any non-ASCII
characters never appear in the pathnames with a new test-lint-* target
as part of a `make test`. To that end, we call `git ls-files` (ensuring
that the paths are quoted properly), relying on the fact that paths
containing non-ASCII characters are quoted within double-quotes.

In case that the source code does not actually live in a Git
repository (e.g. when extracted from a .zip file), or that the `git`
executable cannot be executed, we simply ignore the error for now; In
that case, our trusty Continuous Integration will be the last line of
defense and catch any problematic file name.

Noticed when a topic wanted to add a pathname with '>' in it.  A
check like this will prevent a similar problems from happening in the
future.
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

At the moment difftool's "trust exit code" logic always suppresses the
exit status of the diff utility we invoke.  This is useful because we
don't want to exit just because diff returned "1" because the files
differ, but it's confusing if the shell returns an error because the
selected diff utility is not found.

POSIX specifies 127 as the exit status for "command not found", 126 for
"command found but is not executable" and values greater than 128 if the
command terminated because it received a signal [1] and at least bash
and dash follow this specification, while diff utilities generally use
"1" for the exit status we want to ignore.

Handle any value of 126 or greater as a special value indicating that
some form of fatal error occurred.

[1] http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_08_02Signed-off-by: NJohn Keeping <john@keeping.me.uk>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

When a user asked for a detached HEAD specifically with `--detach`,
we do not need to give advice on what a detached HEAD state entails as
we can assume they know what they're getting into as they asked for it.
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The test added in 71abeb75 (reflog: continue walking the reflog
past root commits, 2016-06-03) contains an unnecessary 'git reflog'
execution, which was part of my debug/tracing instrumentation that I
somehow didn't manage to remove before submitting.
Signed-off-by: NSZEDER Gábor <szeder@ira.uka.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Use the macro FLEX_ALLOC_MEM instead of open-coding it.  This shortens
and simplifies the code a bit.
Signed-off-by: NRene Scharfe <l.s.r@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Convert the name member of struct merge_remote_desc to a FLEX_ARRAY and
use FLEX_ALLOC_STR to build the struct.  This halves the number of
memory allocations, saves the storage for a pointer and avoids an
indirection when reading the name.
Suggested-by: NJeff King <peff@peff.net>
Signed-off-by: NRene Scharfe <l.s.r@web.de>
Reviewed-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

One of the indirect callers of make_virtual_commit() passes the result of
oid_to_hex() as the name, i.e. a pointer to a static buffer.  Since the
function uses that string pointer directly in building a struct
merge_remote_desc, multiple entries can end up sharing the same name
inadvertently.

Fix that by calling set_merge_remote_desc(), which creates a copy of the
string, instead of building the struct by hand.
Signed-off-by: NRene Scharfe <l.s.r@web.de>
Reviewed-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Export a helper function for allocating, populating and attaching a
merge_remote_desc to a commit.
Signed-off-by: NRene Scharfe <l.s.r@web.de>
Reviewed-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Handle allocation errors for the name member just like we already do
for the struct merge_remote_desc itself.
Signed-off-by: NRene Scharfe <l.s.r@web.de>
Reviewed-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

handle_message_id() duplicates the contents of the strbuf that is passed
to it.  Its only caller proceeds to release the strbuf immediately after
that.  Reuse it instead and make that change of object ownership more
obvious by inlining this short function.
Signed-off-by: NRene Scharfe <l.s.r@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This section is about "The FLEXPTR_* variants", so use FLEXPTR_ALLOC_STR
in the example.
Signed-off-by: NRene Scharfe <l.s.r@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>