When we read from a trailer.*.command sub-program, the
current code uses run_command followed by a pipe read, which
can result in deadlock (though in practice you would have to
have a large trailer for this to be a problem). The current
code also leaks the file descriptor for the pipe to the
sub-command.
Instead, let's use capture_command, which makes this simpler
(and we can get rid of our custom helper).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In is_submodule_commit_present, we call run_command followed
by a pipe read, which is prone to deadlock. It is unlikely
to happen in this case, as rev-list should never produce
more than a single line of output, but it does not hurt to
avoid an anti-pattern (and using the helper simplifies the
setup and cleanup).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we spawn "git submodule status" to read its output, we
use run_command() followed by strbuf_read() read from the
pipe. This can deadlock if the subprocess output is larger
than the system pipe buffer.
Furthermore, if start_command() fails, we'll try to read
from a bogus descriptor (probably "-1" or a descriptor we
just closed, but it is a bad idea for us to make assumptions
about how start_command implements its error handling). And
if start_command succeeds, we leak the file descriptor for
the pipe to the child.
All of these can be solved by using the capture_command
helper.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Something as simple as reading the stdout from a command
turns out to be rather hard to do right. Doing:
cmd.out = -1;
run_command(&cmd);
strbuf_read(&buf, cmd.out, 0);
can result in deadlock if the child process produces a large
amount of output. What happens is:
1. The parent spawns the child with its stdout connected
to a pipe, of which the parent is the sole reader.
2. The parent calls wait(), blocking until the child exits.
3. The child writes to stdout. If it writes more data than
the OS pipe buffer can hold, the write() call will
block.
This is a deadlock; the parent is waiting for the child to
exit, and the child is waiting for the parent to call
read().
So we might try instead:
start_command(&cmd);
strbuf_read(&buf, cmd.out, 0);
finish_command(&cmd);
But that is not quite right either. We are examining cmd.out
and running finish_command whether start_command succeeded
or not, which is wrong. Moreover, these snippets do not do
any error handling. If our read() fails, we must make sure
to still call finish_command (to reap the child process).
And both snippets failed to close the cmd.out descriptor,
which they must do (provided start_command succeeded).
Let's introduce a run-command helper that can make this a
bit simpler for callers to get right.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We call strbuf_read(), and want to know whether we got any
output. To do so, we assign the result to a size_t, and
check whether it is non-zero.
But strbuf_read returns a signed ssize_t. If it encounters
an error, it will return -1, and we'll end up treating this
the same as if we had gotten output. Instead, we can just
check whether our buffer has anything in it (which is what
we care about anyway, and is the same thing since we know
the buffer was empty to begin with).
Note that the "len" variable actually has two roles in this
function. Now that we've eliminated the first, we can push the
declaration closer to the point of use for the second one.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is a holdover from the original implementation in
ac8d5af (builtin-status: submodule summary support,
2008-04-12), which just had the sub-process output to our
descriptor; we had to make sure we had flushed any data that
we produced before it started writing.
Since 3ba7407 (submodule summary: ignore --for-status
option, 2013-09-06), however, we pipe the sub-process output
back to ourselves. So there's no longer any need to flush
(it does not hurt, but it may leave readers wondering why we
do it).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Test clean-up.
* jc/diff-test-updates:
test_ln_s_add: refresh stat info of fake symbolic links
t4008: modernise style
t/diff-lib: check exact object names in compare_diff_raw
tests: do not borrow from COPYING and README from the real source
t4010: correct expected object names
t9300: correct expected object names
t4008: correct stale comments
A corrupt input to "git diff -M" can cause us to segfault.
* jk/diffcore-rename-duplicate:
diffcore-rename: avoid processing duplicate destinations
diffcore-rename: split locate_rename_dst into two functions
The borrowed code in kwset API did not follow our usual convention
to use "unsigned char" to store values that range from 0-255.
* bw/kwset-use-unsigned:
kwset: use unsigned char to store values with high-bit set
Description given by "grep -h" for its --exclude-standard option
was phrased poorly.
* nd/grep-exclude-standard-help-fix:
grep: correct help string for --exclude-standard
"git remote add" mentioned "--tags" and "--no-tags" and was not
clear that fetch from the remote in the future will use the default
behaviour when neither is given to override it.
* mg/doc-remote-tags-or-not:
git-remote.txt: describe behavior without --tags and --no-tags
"git diff --shortstat --dirstat=changes" showed a dirstat based on
lines that was never asked by the end user in addition to the
dirstat that the user asked for.
* mk/diff-shortstat-dirstat-fix:
diff --shortstat --dirstat: remove duplicate output
The interaction between "git submodule update" and the
submodule.*.update configuration was not clearly documented.
* ms/submodule-update-config-doc:
submodule: improve documentation of update subcommand
"git apply" was not very careful about reading from, removing,
updating and creating paths outside the working tree (under
--index/--cached) or the current directory (when used as a
replacement for GNU patch).
* jc/apply-beyond-symlink:
apply: do not touch a file beyond a symbolic link
apply: do not read from beyond a symbolic link
apply: do not read from the filesystem under --index
apply: reject input that touches outside the working area
"git daemon" looked up the hostname even when "%CH" and "%IP"
interpolations are not requested, which was unnecessary.
* rs/daemon-interpolate:
daemon: use callback to build interpolated path
daemon: look up client-supplied hostname lazily
The "interpolated-path" option of "git daemon" inserted any string
client declared on the "host=" capability request without checking.
Sanitize and limit %H and %CH to a saner and a valid DNS name.
* jk/daemon-interpolate:
daemon: sanitize incoming virtual hostname
t5570: test git-daemon's --interpolated-path option
git_connect: let user override virtual-host we send to daemon
Code cleanups.
* rs/simple-cleanups:
sha1_name: use strlcpy() to copy strings
pretty: use starts_with() to check for a prefix
for-each-ref: use skip_prefix() to avoid duplicate string comparison
connect: use strcmp() for string comparison
The configuration variable 'mailinfo.scissors' was hard to
discover in the documentation.
* mm/am-c-doc:
Documentation/git-am.txt: mention mailinfo.scissors config variable
Documentation/config.txt: document mailinfo.scissors
Correct a breakage to git-svn around v2.2 era that triggers
premature closing of FileHandle.
* ew/svn-maint-fixes:
Git::SVN::*: avoid premature FileHandle closure
git-svn: fix localtime=true on non-glibc environments
Even though we officially haven't dropped Perl 5.8 support, the
Getopt::Long package that came with it does not support "--no-"
prefix to negate a boolean option; manually add support to help
people with older Getopt::Long package.
* km/send-email-getopt-long-workarounds:
git-send-email.perl: support no- prefix with older GetOptions
"update-index --refresh" used to leak when an entry cannot be
refreshed for whatever reason.
* sb/plug-leak-in-make-cache-entry:
read-cache.c: free cache entry when refreshing fails
"git fast-import" used to crash when it could not close and
conclude the resulting packfile cleanly.
* jk/fast-import-die-nicely-fix:
fast-import: avoid running end_packfile recursively
In v2.2.0, we broke "git prune" that runs in a repository that
borrows from an alternate object store.
* jk/prune-mtime:
sha1_file: fix iterating loose alternate objects
for_each_loose_file_in_objdir: take an optional strbuf path
Certain older vintages of cURL give irregular output from
"curl-config --vernum", which confused our build system.
* tc/curl-vernum-output-broken-in-7.11:
Makefile: handle broken curl version number in version check
An earlier workaround to squelch unhelpful deprecation warnings
from the complier on Mac OSX unnecessarily set minimum required
version of the OS, which the user might want to raise (or lower)
for other reasons.
* es/squelch-openssl-warnings-on-macosx:
git-compat-util: do not step on MAC_OS_X_VERSION_MIN_REQUIRED
Longstanding configuration variable naming rules has been added to
the documentation.
* jc/conf-var-doc:
CodingGuidelines: describe naming rules for configuration variables
config.txt: mark deprecated variables more prominently
config.txt: clarify that add.ignore-errors is deprecated
The credential helper for Windows (in contrib/) used to mishandle
a user name with an at-sign in it.
* av/wincred-with-at-in-username-fix:
wincred: fix get credential if username has "@"
Older GnuPG implementations may not correctly import the keyring
material we prepare for the tests to use.
* ch/new-gpg-drops-rfc-1991:
t/lib-gpg: sanity-check that we can actually sign
t/lib-gpg: include separate public keys in keyring.gpg
Clarify in the documentation that "remote.<nick>.pushURL" and
"remote.<nick>.URL" are there to name the same repository accessed
via different transports, not two separate repositories.
* jc/remote-set-url-doc:
Documentation/git-remote.txt: stress that set-url is not for triangular
Reading configuration from a blob object, when it ends with a lone
CR, use to confuse the configuration parser.
* jk/config-no-ungetc-eof:
config_buf_ungetc: warn when pushing back a random character
config: do not ungetc EOF
We didn't format an integer that wouldn't fit in "int" but in
"uintmax_t" correctly.
* jk/decimal-width-for-uintmax:
decimal_width: avoid integer overflow
"git push --signed" gave an incorrectly worded error message when
the other side did not support the capability.
* jc/push-cert:
transport-helper: fix typo in error message when --signed is not supported
"git fetch" over a remote-helper that cannot respond to "list"
command could not fetch from a symbolic reference e.g. HEAD.
* mh/deref-symref-over-helper-transport:
transport-helper: do not request symbolic refs to remote helpers
The insn sheet "git rebase -i" creates did not fully honor
core.abbrev settings.
* ks/rebase-i-abbrev:
rebase -i: use full object name internally throughout the script
The tests that wanted to see that file becomes unreadable after
running "chmod a-r file", and the tests that wanted to make sure it
is not run as root, we used "can we write into the / directory?" as
a cheap substitute, but on some platforms that is not a good
heuristics. The tests and their prerequisites have been updated to
check what they really require.
* jk/sanity:
test-lib.sh: set prerequisite SANITY by testing what we really need
tests: correct misuses of POSIXPERM
t/lib-httpd: switch SANITY check for NOT_ROOT
A future breakage to "git push" to make it incorrectly pay attention
to pushInsteadOf when it should not will be left uncaught without
this change.
Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The documentation of 'git submodule update' has several problems:
1) It mentions that value 'none' of submodule.$name.update can be
overridden by --checkout, but other combinations of configuration
values and command line options are not mentioned.
2) The documentation of submodule.$name.update is scattered across three
places, which is confusing.
3) The documentation of submodule.$name.update in gitmodules.txt is
incorrect, because the code always uses the value from .git/config
and never from .gitmodules.
4) Documentation of --force was incomplete, because it is only effective
in case of checkout method of update.
Fix all these problems by documenting submodule.*.update in
git-submodule.txt and make everybody else refer to it.
Helped-by: Junio C Hamano <gitster@pobox.com>
Helped-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Michal Sojka <sojkam1@fel.cvut.cz>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
