To test check-ignore's --stdin feature, we use two fifos to
send and receive data. We carefully keep a descriptor to its
input open so that it does not receive EOF between input
lines. However, we do not do the same for its output. That
means there is a potential race condition in which
check-ignore has opened the output pipe once (when we read
the first line), and then writes the second line before we
have re-opened the pipe.
In that case, check-ignore gets a SIGPIPE and dies. The
outer shell then tries to open the output fifo but blocks
indefinitely, because there is no writer. We can fix it by
keeping a descriptor open through the whole procedure.
This should also help if check-ignore dies for any other
reason (we would already have opened the fifo and would
therefore not block, but just get EOF on read).
However, we are technically still susceptible to
check-ignore dying early, before we have opened the fifo.
This is an unlikely race and shouldn't generally happen in
practice, though, so we can hopefully ignore it.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
sleeps in the check-ignore test suite are not ideal since they can
fail when the system is under load, or when a tool like valgrind is
used which drastically alters the timing. Therefore we replace them
with a more robust solution using a named pipe (FIFO).
Thanks to Jeff King for coming up with the redirection wizardry
required to make this work.
http://article.gmane.org/gmane.comp.version-control.git/220916
Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some callers, such as the git-annex web assistant, find it useful to
invoke git check-ignore as a persistent background process, which can
then have queries fed to its STDIN at any point, and the corresponding
response consumed from its STDOUT. For this we need to invoke
check_ignore() once per line of standard input, and flush standard
output after each result.
The above use case suggests that empty STDIN is actually a reasonable
scenario (e.g. when the caller doesn't know in advance whether any
queries need to be fed to the background process until after it's
already started), so we make the minor behavioural change that "no
pathspec given." is no longer emitted in when STDIN is empty.
Even though check_ignore() could now be changed to operate on a single
pathspec, we keep it operating on an array of pathspecs since that is
a more convenient way of consuming the existing pathspec API.
Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If `-n` or `--non-matching` are specified, non-matching pathnames will
also be output, in which case all fields in each output record except
for <pathname> will be empty. This can be useful when running
check-ignore as a background process, so that files can be
incrementally streamed to STDIN, and for each of these files, STDOUT
will indicate whether that file matched a pattern or not. (Without
this option, it would be impossible to tell whether the absence of
output for a given file meant that it didn't match any pattern, or
that the result simply hadn't been flushed to STDOUT yet.)
Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The expected contents of STDOUT for the final --stdin tests can be
derived from the expected contents of STDOUT for the same tests when
--verbose is given, in the same way that test_expect_success_multi
derives this for earlier tests.
Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Usually we do not pass an empty string to the function hash_name()
because we almost always ask for hash values for a path that is a
candidate to be added to the index. However, check-ignore (and most
likely check-attr, but I didn't check) apparently has a callchain
to ask the hash value for an empty path when it was given a "." from
the top-level directory to ask "Is the path . excluded by default?"
Make sure that hash_name() does not overrun the end of the given
pathname even when it is empty.
Remove a sweep-the-issue-under-the-rug conditional in check-ignore
that avoided to pass an empty string to the callchain while at it.
It is a valid question to ask for check-ignore if the top-level is
set to be ignored by default, even though the answer is most likely
no, if only because there is currently no way to specify such an
entry in the .gitignore file. But it is an unusual thing to ask and
it is not worth optimizing for it by special casing at the top level
of the call chain.
Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
test_expect_success_multi() helper function warrants some explanation,
since at first sight it may seem like generic test framework plumbing,
but is in fact specific to testing check-ignore, and allows more
thorough testing of the various output formats without significantly
increase the size of t0008.
Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Brace expansion is a shell feature that's not required by POSIX and not
supported by dash nor NetBSD's sh. Explicitly list all combinations
instead. Also avoid calling touch by creating the test files with a
redirection instead, as suggested by Junio.
Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
