It is sometimes useful to be able to read exactly N bytes from a
pipe. Doing this portably turns out to be surprisingly difficult
in shell scripts.
We want a solution that:
- is portable
- never reads more than N bytes due to buffering (which
would mean those bytes are not available to the next
program to read from the same pipe)
- handles partial reads by looping until N bytes are read
(or we see EOF)
- is resilient to stray signals giving us EINTR while
trying to read (even though we don't send them, things
like SIGWINCH could cause apparently-random failures)
Some possible solutions are:
- "head -c" is not portable, and implementations may
buffer (though GNU head does not)
- "read -N" is a bash-ism, and thus not portable
- "dd bs=$n count=1" does not handle partial reads. GNU dd
has iflags=fullblock, but that is not portable
- "dd bs=1 count=$n" fixes the partial read problem (all
reads are 1-byte, so there can be no partial response).
It does make a lot of write() calls, but for our tests
that's unlikely to matter. It's fairly portable. We
already use it in our tests, and it's unlikely that
implementations would screw up any of our criteria. The
most unknown one would be signal handling.
- perl can do a sysread() loop pretty easily. On my Linux
system, at least, it seems to restart the read() call
automatically. If that turns out not to be portable,
though, it would be easy for us to handle it.
That makes the perl solution the least bad (because we
conveniently omitted "length of code" as a criterion).
It's also what t9300 is currently using, so we can just pull
the implementation from there.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It turns out that the earlier effort to update the heuristics may
want to use a bit more time to mature. Turn it off by default.
* jk/diff-compact-heuristic:
diff: disable compaction heuristic for now
http://lkml.kernel.org/g/20160610075043.GA13411@sigill.intra.peff.net
reports that a change to add a new "function" with common ending
with the existing one at the end of the file is shown like this:
def foo
do_foo_stuff()
+ common_ending()
+end
+
+def bar
+ do_bar_stuff()
+
common_ending()
end
when the new heuristic is in use. In reality, the change is to add
the blank line before "def bar" and everything below, which is what
the code without the new heuristic shows.
Disable the heuristics by default, and resurrect the documentation
for the option and the configuration variables, while clearly
marking the feature as still experimental.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "are we talking with TTY, doing an interactive session?"
detection has been updated to work better for "Git for Windows".
* kb/msys2-tty:
mingw: make isatty() recognize MSYS2's pseudo terminals (/dev/pty*)
A couple of bugs around core.autocrlf have been fixed.
* tb/core-eol-fix:
convert.c: ident + core.autocrlf didn't work
t0027: test cases for combined attributes
convert: allow core.autocrlf=input and core.eol=crlf
t0027: make commit_chk_wrnNNO() reliable
Many commands normalize command line arguments from NFD to NFC
variant of UTF-8 on OSX, but commands in the "diff" family did
not, causing "git diff $path" to complain that no such path is
known to Git. They have been taught to do the normalization.
* ar/diff-args-osx-precompose:
diff: run arguments through precompose_argv
A bash-ism "local" has been removed from "git submodule" scripted
Porcelain.
* sb/submodule-helper-relative-path:
submodule: remove bashism from shell script
The way how "submodule--helper list" signals unmatch error to its
callers has been updated.
* sb/submodule-helper-list-signal-unmatch-via-exit-status:
submodule--helper: offer a consistent API
The mark-up in the top-level README.md file has been updated to
typeset CLI command names differently from the body text.
* bd/readme.markdown-more:
README.md: format CLI commands with code syntax
The manpage output of our documentation did not render well in
terminal; typeset literals in bold by default to make them stand
out more.
* em/man-bold-literal:
Documentation: bold literals in man
"git cherry-pick --help" had three instances of word "behavior",
one of which was spelled "behaviour", which is updated to match the
other two.
* pa/cherry-pick-doc-typo:
git-cherry-pick.txt: correct a small typo
"git rebase -i", after it fails to auto-resolve the conflict, had
an unnecessary call to "git rerere" from its very early days, which
was spotted recently; the call has been removed.
* js/rebase-i-dedup-call-to-rerere:
rebase -i: remove an unnecessary 'rerere' invocation
The one in 'master' has a brown-paper-bag bug that breaks the perf
test when used inside a usual Git repository with a working tree.
* js/perf-rebase-i:
perf: make the tests work without a worktree
When we run scripted Porcelains, "git" potty has set up the $PATH by
prepending $GIT_EXEC_PATH, the path given by "git --exec-path=$there
$cmd", etc. already. Because of this, scripted Porcelains can
dot-source shell script library like git-sh-setup with simple dot
without specifying any path.
t2300 however dot-sources git-sh-setup without adjusting $PATH like
the real "git" potty does. This has not been a problem so far, but
once git-sh-setup wants to rely on the $PATH adjustment, just like
any scripted Porcelains already do, it would become one. It cannot
for example dot-source another shell library without specifying the
full path to it by prefixing $(git --exec-path).
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In t5500::check_prot_host_port_path(), diagport is not a variable
used elsewhere and the function is not recursively called so this
can simply lose the "local", which may not be supported by shell
(besides, the function liberally clobbers other variables without
making them "local").
t7403::reset_submodule_urls() overrides the "root" variable used
in the test framework for no good reason; its use is not about
temporarily relocating where the test repositories are created.
This assignment can be made not to clobber the variable by moving
them into the subshells it already uses. Its value is always
$TRASH_DIRECTORY, so we could use it instead there, and this
function that is called only once and its two subshells may not be
necessary (instead, the caller can use "git -C $there config" and
set a value that is derived from $TRASH_DIRECTORY), but this is a
minimum fix that is needed to lose "local".
Helped-by: John Keeping <john@keeping.me.uk>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio pointed out `relative_path` was using bashisms via the
local variables. As the longer term goal is to rewrite most of the
submodule code in C, do it now.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 48308681 (2016-02-29, git submodule update: have a dedicated helper
for cloning), the helper communicated errors back only via exit code,
and dance with printing '#unmatched' in case of error was left to
git-submodule.sh as it uses the output of the helper and pipes it into
shell commands. This change makes the helper consistent by never
printing '#unmatched' in the helper but always handling these piping
issues in the actual shell script.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This does not change the behavior, but allows the user to tweak
DEVELOPER_CFLAGS on the command-line or in a config.mak* file if
needed.
This also makes the code somewhat cleaner as it follows the pattern
<initialisation of variables>
<include statements>
<actual build logic>
by specifying which flags to activate in the first part, and actually
activating them in the last one.
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The one-shot environment variable syntax:
FOO=BAR some-program
is unportable when some-program is actually a shell
function, like test_must_fail (on some shells FOO remains
set after the function returns, and on others it does not).
We sometimes get around this by using env, like:
test_must_fail env FOO=BAR some-program
But that only works because test_must_fail's arguments are
themselves a command which can be run. You can't run:
env FOO=BAR test_must_fail some-program
because env does not know about our shell functions. So
there is no equivalent for test_commit, for example, and one
must resort to:
(
FOO=BAR
export FOO
test_commit
)
which is a bit verbose. Let's add a version of "env" that
works _inside_ the shell, by creating a subshell, exporting
variables from its argument list, and running the command.
Its use is demonstrated on a currently-unportable case in
t4014.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Correct faulty recommendation to use "git submodule deinit ." when
de-initialising all submodules, which would result in a strange
error message in a pathological corner case.
* sb/submodule-deinit-all:
submodule deinit: require '--all' instead of '.' for all submodules
"http.cookieFile" configuration variable clearly wants a pathname,
but we forgot to treat it as such by e.g. applying tilde expansion.
* bn/http-cookiefile-config:
http: expand http.cookieFile as a path
Documentation: config: improve word ordering for http.cookieFile
Running tests with '-x' option to trace the individual command
executions is a useful way to debug test scripts, but some tests
that capture the standard error stream and check what the command
said can be broken with the trace output mixed in. When running
our tests under "bash", however, we can redirect the trace output
to another file descriptor to keep the standard error of programs
being tested intact.
* jk/test-send-sh-x-trace-elsewhere:
test-lib: set BASH_XTRACEFD automatically
"git describe --contains" often made a hard-to-justify choice of
tag to give name to a given commit, because it tried to come up
with a name with smallest number of hops from a tag, causing an old
commit whose close descendant that is recently tagged were not
described with respect to an old tag but with a newer tag. It did
not help that its computation of "hop" count was further tweaked to
penalize being on a side branch of a merge. The logic has been
updated to favor using the tag with the oldest tagger date, which
is a lot easier to explain to the end users: "We describe a commit
in terms of the (chronologically) oldest tag that contains the
commit."
* js/name-rev-use-oldest-ref:
name-rev: include taggerdate in considering the best name
Interactive rebase uses 'git cherry-pick' and 'git merge' to replay
commits. Both invoke the 'rerere' machinery when they fail due to merge
conflicts. Note that all code paths with these two commands also invoke
the shell function die_with_patch when the commands fail.
Since commit 629716d2 ("rerere: do use multiple variants") the second
operation of the rerere machinery can be observed by a duplicated
message "Recorded preimage for 'file'". This second operation records
the same preimage as the first one and, hence, only wastes cycles.
Remove the 'git rerere' invocation from die_with_patch.
Shell function die_with_patch can be called after the failure of
"git commit", too, which also calls into the rerere machinery, but it
does so only after a successful commit to record the resolution.
Therefore, it is wrong to call 'git rerere' from die_with_patch after
"git commit" fails.
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In regular repositories $source_git and $objects_dir contain relative
paths based on $source. Go there to allow cp to resolve them.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
test updates to make it more readable and maintainable.
* es/t1500-modernize:
t1500: avoid setting environment variables outside of tests
t1500: avoid setting configuration options outside of tests
t1500: avoid changing working directory outside of tests
t1500: test_rev_parse: facilitate future test enhancements
t1500: be considerate to future potential tests