sane_execvp(): ignore non-directory on $PATH

When you have a non-directory on your PATH, a funny thing happens:

	$ PATH=$PATH:/bin/sh git foo
	fatal: cannot exec 'git-foo': Not a directory?

Worse yet, as real commands always take precedence over aliases,
this behaviour interacts rather badly with them:

	$ PATH=$PATH:/bin/sh git -c alias.foo=show git foo -s
	fatal: cannot exec 'git-foo': Not a directory?

This is because an ENOTDIR error from the underlying execvp(2) is
reported back to the caller of our sane_execvp() wrapper as-is.

Translating it to ENOENT, just like the case where we _might_ have
the command in an unreadable directory, fixes it.  Without an alias,
we would get

	git: 'foo' is not a git command. See 'git --help'.

and we use the 'foo' alias when it is available, of course.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
macos: lazily initialize iconv

In practice, the majority of paths do not have utf8 that needs
the canonicalization. Lazily call iconv_open()/iconv_close() to
avoid unnecessary overhead.

Credits to Ralf Thielow and Linus Torvalds for reviews and
comments.  Bugs are still mine.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
send-email: improve RFC2047 quote parsing

The RFC2047 unquoting, used to parse email addresses in From and Cc
headers, is broken in several ways:

* It erroneously substitutes ' ' for '_' in *the whole* header, even
  outside the quoted field. [Noticed by Christoph.]

* It is too liberal in its matching, and happily matches the start
  of one quoted chunk against the end of another, or even just
  something that looks like such an end. [Noticed by Junio.]

* It fundamentally cannot cope with encodings that are not a
  superset of ASCII, nor several (incompatible) encodings in the
  same header.

This patch fixes the first two by doing a more careful decoding of
the outer quoting (e.g. "=AB" to represent an octet whose value is
0xAB).  Fixing the fundamental issues is left for a future, more
intrusive, patch.

Noticed-by: Christoph Miebach <christoph.miebach@web.de>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
setup: clarify error messages for file/revisions ambiguity

The previous "Use '--' to separate filenames from revisions" may sound
obvious for an old-time Unix user, but does not make it clear how to use
this '--'. In addition to mentionning this '--', give an idea of what the
new command should look like.

Ideally, we could provide cut-and-paste ready commands based on the
command that just failed, but we have no easy access to argv[] in this
place of the code.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
grep: add a grep.patternType configuration setting

The grep.extendedRegexp configuration setting enables the -E flag on grep
by default but there are no equivalents for the -G, -F and -P flags.

Rather than adding an additional setting for grep.fooRegexp for current
and future pattern matching options, add a grep.patternType setting that
can accept appropriate values for modifying the default grep pattern
matching behavior. The current values are "basic", "extended", "fixed",
"perl" and "default" for setting -G, -E, -F, -P and the default behavior
respectively.

When grep.patternType is set to a value other than "default", the
grep.extendedRegexp setting is ignored. The value of "default" restores
the current default behavior, including the grep.extendedRegexp
behavior.

Signed-off-by: J Smith <dark.panda@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff_setup_done(): return void

diff_setup_done() has historically returned an error code, but lost
the last nonzero return in 943d5b7 (allow diff.renamelimit to be set
regardless of -M/-C, 2006-08-09).  The callers were in a pretty
confused state: some actually checked for the return code, and some
did not.

Let it return void, and patch all callers to take this into account.
This conveniently also gets rid of a handful of different(!) error
messages that could never be triggered anyway.

Note that the function can still die().

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-recursive: eliminate flush_buffer() in favor of write_in_full()

flush_buffer() is a thin wrapper around write_in_full() with two very
confusing properties:

* It runs a loop to handle short reads, ensuring that we write
  everything.  But that is precisely what write_in_full() does!

* It checks for a return value of 0 from write_in_full(), which cannot
  happen: it returns this value only if count=0, but flush_buffer()
  will never call write_in_full() in this case.

Remove it.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
include agent identifier in capability string

Instead of having the client advertise a particular version
number in the git protocol, we have managed extensions and
backwards compatibility by having clients and servers
advertise capabilities that they support. This is far more
robust than having each side consult a table of
known versions, and provides sufficient information for the
protocol interaction to complete.

However, it does not allow servers to keep statistics on
which client versions are being used. This information is
not necessary to complete the network request (the
capabilities provide enough information for that), but it
may be helpful to conduct a general survey of client
versions in use.

We already send the client version in the user-agent header
for http requests; adding it here allows us to gather
similar statistics for non-http requests.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
cherry-pick: add --allow-empty-message option

Scripts such as "git rebase -i" cannot currently cherry-pick commits
which have an empty commit message, as git cherry-pick calls git
commit without the --allow-empty-message option.

Add an --allow-empty-message option to git cherry-pick which is passed
through to git commit, so this behaviour can be overridden.

Signed-off-by: Chris Webb <chris@arachsys.com>
Reviewed-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Documentation: do not mention .git/refs/* directories

It is an implementation detail that a new tag is created by adding a
file in the .git/refs/tags directory.  The only thing the user needs
to know is that a "git tag" creates a ref in the refs/tags namespace,
and without "-f", it does not overwrite an existing tag.

Inspired by a report from 乙酸鋰 <ch3cooli@gmail.com>; I think I
caught all the existing mention in Documentation/ directory in the
tip of 1.7.9.X maintenance track, but we may have added new ones
since then.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
fetch/push: allow refs/*:refs/*

There are a handful of places where we call check_refname_format() on a
substring after "refs/" of a refname we are going to use, and filter out a
valid match with "refs/stash" with such a pathspec.  Not sending a stash
may arguably be a feature (as stash is inherently a local workflow
element), but the code in the transport layer is oblivious to this
filtering performed by the lower layer of the code, and complains that the
other side did not send all the objects that needs to complete refs/stash
at the end, even though the code will not write refs/stash out anyway, and
making the whole command fail.

This is an attempt to "fix" it by using check_refname_format() on the
whole "refs/....." string and allowing refs/stash to be also copied.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
get_fetch_map(): tighten checks on dest refs

The code to check the refname we store the fetched result locally did not
bother checking the first 5 bytes of it, presumably assuming that it
always begin with "refs/".  For a fetch refspec (or the result of applying
wildcard on one), we always want the RHS to map to something inside
"refs/" hierarchy, so let's spell that rule out in a more explicit way.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
docs: monospace listings in docbook output

When asciidoc converts a listing block like:

----------------------
$ git log --merge
----------------------

it marks it to be displayed in a monospace font. This works
fine when generating HTML output. However, when generating
docbook output, we override the expansion of a listingblock
to work around bugs in some versions of the docbook
toolchain. Our override did not mark the listingblock with
the "monospaced" class.

The main output that uses docbook as an intermediate format
is the manpages. We didn't notice any issue there because
the monospaced class seems to be ignored when generating
roff from the docbook manpages.

However, when generating texinfo to make info pages, docbook
does respect this class. The resulting texinfo output
properly uses "@example" blocks to display the listing in
this case. Besides possibly looking prettier in some texinfo
backends,  one important effect is that the monospace font
suppresses texinfo's expansion of "--" and "---" into
en-dashes and em-dashes.  With the current code, the example
above ends up looking like "git log -merge", which is
confusing and wrong.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
prune.c: only print informational message in show_only or verbose mode

"git prune" reports removal of loose object files that are no longer
necessary only under the "-v" option, but unconditionally reports
removal of temporary files that are no longer needed.

The original thinking was that the presence of a leftover temporary
file should be an unusual occurrence that may indicate an earlier
failure of some sort, and the user may want to be reminded of it.
Removing an unnecessary loose object file, on the other hand, is
just part of the normal operation.  That is why the former is always
printed out and the latter only when -v is used.

But neither report is particularly useful.  Hide both of these
behind the "-v" option for consistency.

Signed-off-by: Brandon Casey <drafnel@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'jc/maint-sane-execvp-notdir' into jch

"git foo" errored out with "Not a directory" when the user had a non
directory on $PATH, and worse yet it masked an alias "foo" to run.

Not urgent (non regression).

* jc/maint-sane-execvp-notdir:
  sane_execvp(): ignore non-directory on $PATH
Merge branch 'jc/sanitize-nkd-lazy-iconv-open' into jch

Teach the code that works around NKD/NKC gotcha on MacOS to call
iconv_open() only when it is necessary, in the hope of avoiding
set-up overhead.

Not urgent (non regression).

* jc/sanitize-nkd-lazy-iconv-open:
  macos: lazily initialize iconv
Merge branch 'tr/maint-send-email-2047' into jch

"git send-email" did not unquote encoded words that appear on the
header correctly, and lost "_" from strings.

Not urgent (non regression).

* tr/maint-send-email-2047:
  send-email: improve RFC2047 quote parsing
Merge branch 'cw/cherry-pick-allow-empty-message' into jch

"git cherry-pick" by default stops when it sees a commit without any
log message.  The "--allow-empty-message" option can be used to
silently proceed.

Not urgent (non regression).

* cw/cherry-pick-allow-empty-message:
  cherry-pick: add --allow-empty-message option
Merge branch 'jk/version-string' into jch

Leftover bits from the "git version" code restructuring, that
actually give us an ability to expose the Git version over the wire
in the protocol exchange.

* jk/version-string:
  include agent identifier in capability string
Merge branch 'mm/die-with-dashdash-help' into jch

Reword error messages.

* mm/die-with-dashdash-help:
  setup: clarify error messages for file/revisions ambiguity