push: fix segfault when HEAD points nowhere

After a push of a branch other than the current branch fails in
a no-ff error and if you are still on an unborn branch, the code
recently added to report the failure dereferenced a null pointer
while checking the name of the current branch.

Signed-off-by: Fraser Tweedale <frase@frase.id.au>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
gpg: close stderr once finished with it in verify_signed_buffer()

Failing to close the stderr pipe in verify_signed_buffer() causes
git to run out of file descriptors if there are many calls to
verify_signed_buffer(). An easy way to trigger this is to run

 git log --show-signature --merges | grep "key"

on the linux kernel git repo. Eventually it will fail with

 error: cannot create pipe for gpg: Too many open files
 error: could not run gpg.

Close the stderr pipe so that this can't happen.

Suggested-by: Jeff King <peff@peff.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-am: record full index line in the patch used while rebasing

Earlier, a230949 (am --rebasing: get patch body from commit, not
from mailbox, 2012-06-26) learned to regenerate patch body from the
commit object while rebasing, instead of reading from the rebase-am
front-end.  While doing so, it used "git diff-tree" but without
giving it the "--full-index" option.

This does not matter for in-repository objects; during rebasing, any
abbreviated object name should uniquely identify them.

But we may be rebasing a commit that contains a change to a gitlink,
in which case we usually should not have the object (it names a
commit in the submodule).  A full object name is necessary to later
reconstruct a fake ancestor index for them.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
apply: simplify build_fake_ancestor()

The local variable sha1_ptr in the build_fake_ancestor() function
used to either point at the null_sha1[] (if the ancestor did not
have the path) or at sha1[] (if we read the object name into the
local array), but 7a98869 (apply: get rid of --index-info in favor
of --build-fake-ancestor, 2007-09-17) made the "missing in the
ancestor" case unnecessary, hence sha1_ptr, when used, always points
at the local array.

Get rid of the unneeded variable, and restructure the if/else
cascade a bit to make it easier to read.  There should be no
behaviour change.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
apply: diagnose incomplete submodule object name better

"git am -3" uses this function to build a tree that records how the
preimage the patch was created from would have looked like.  An
abbreviated object name on the index line is ordinarily sufficient
for us to figure out the object name the preimage tree would have
contained, but a change to a submodule by definition shows an object
name of a submodule commit which our repository should not have, and
get_sha1_blob() is not an appropriate way to read it (or get_sha1()
for that matter).

Use get_sha1_hex() and complain if we do not find a full object name
there.

We could read from the payload part of the patch to learn the full
object name of the commit, but the primary user "git rebase" has
been fixed to give us a full object name, so this should suffice
for now.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
Documentation: avoid poor-man's small caps GIT

In the earlier days, we used to spell the name of the system as GIT,
to simulate as if it were typeset with capital G and IT in small
caps.  Later we stopped doing so at around 1.6.5 days.

Let's stop doing so throughout the documentation.  The name to refer
to the whole system (and the concept it embodies) is "Git"; the
command end-users type is "git".  And document this in the coding
guideline.

Signed-off-by: Thomas Ackermann <th.acker@arcor.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Documentation: the name of the system is 'Git', not 'git'

Signed-off-by: Thomas Ackermann <th.acker@arcor.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Documentation: do not use undefined terms git-dir and git-file

We will add gitfile to the glossary in a separate commit.

Signed-off-by: Thomas Ackermann <th.acker@arcor.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Documentation: add a description for 'gitfile' to glossary

Signed-off-by: Thomas Ackermann <th.acker@arcor.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Documentation: describe the "repository" in repository-layout

Update the introductory part and concisely explain how gitfile is
handled, what it is used for and for what effect.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
Documentation: StGit is the right spelling, not StGIT

They refer themselves as such at https://gna.org/projects/stgit/

Signed-off-by: Thomas Ackermann <th.acker@arcor.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Makefile: explicitly set target name for autogenerated dependencies

"gcc -MF depfile -MMD -MP -c -o path/to/file.o" produces a makefile
snippet named "depfile" describing what files are needed to build the
target given by "-o".  When ccache versions before v3.0pre0~187 (Fix
handling of the -MD and -MDD options, 2009-11-01) run, they execute

	gcc -MF depfile -MMD -MP -E

instead to get the final content for hashing.  Notice that the "-c -o"
combination is replaced by "-E".  The result is a target name without
a leading path.

Thus when building git with such versions of ccache with
COMPUTE_HEADER_DEPENDENCIES enabled, the generated makefile snippets
define dependencies for the wrong target:

	$ make builtin/add.o
	GIT_VERSION = 1.7.8.rc3
	    * new build flags or prefix
	    CC builtin/add.o
	$ head -1 builtin/.depend/add.o.d
	add.o: builtin/add.c cache.h git-compat-util.h compat/bswap.h strbuf.h \

After a change in a header file, object files in a subdirectory are
not automatically rebuilt by "make":

	$ touch cache.h
	$ make builtin/add.o
	$

Luckily we can prevent trouble by explicitly supplying the name of the
target to ccache and gcc, using the -MQ option.  Do so.

Reported-and-tested-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Reported-by: : 허종만 <jongman.heo@samsung.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'ft/transport-report-segv'

A failure to push due to non-ff while on an unborn branch
dereferenced a NULL pointer when showing an error message.

* ft/transport-report-segv:
  push: fix segfault when HEAD points nowhere
Merge branch 'sb/gpg-plug-fd-leak'

We forgot to close the file descriptor reading from "gpg" output,
killing "git log --show-signature" on a long history.

* sb/gpg-plug-fd-leak:
  gpg: close stderr once finished with it in verify_signed_buffer()
Merge branch 'jc/fake-ancestor-with-non-blobs'

Rebasing the history of superproject with change in the submodule
was broken since v1.7.12.

* jc/fake-ancestor-with-non-blobs:
  apply: diagnose incomplete submodule object name better
  apply: simplify build_fake_ancestor()
  git-am: record full index line in the patch used while rebasing
Merge branch 'ta/doc-no-small-caps'

Update documentation to change "GIT" which was a poor-man's small
caps to "Git".  The latter was the intended spelling.

Also change "git" spelled in all-lowercase to "Git" when it refers
to the system as the whole or the concept it embodies, as opposed to
the command the end users would type.

* ta/doc-no-small-caps:
  Documentation: StGit is the right spelling, not StGIT
  Documentation: describe the "repository" in repository-layout
  Documentation: add a description for 'gitfile' to glossary
  Documentation: do not use undefined terms git-dir and git-file
  Documentation: the name of the system is 'Git', not 'git'
  Documentation: avoid poor-man's small caps GIT
Merge branch 'jn/auto-depend-workaround-buggy-ccache'

An age-old workaround to prevent buggy versions of ccache from
breaking the auto-generation of dependencies, which unfortunately
is still relevant because some people use ancient distros.

* jn/auto-depend-workaround-buggy-ccache:
  Makefile: explicitly set target name for autogenerated dependencies
Update draft release notes to 1.8.2

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