When performing tag following, in addition to using the server's
"include-tag" capability to send tag objects (and emulating it if the
server does not support that capability), "git fetch" relies upon the
presence of refs/tags/* entries in the initial ref advertisement to
locally create refs pointing to the aforementioned tag objects. When
using protocol v2, refs/tags/* entries in the initial ref advertisement
may be suppressed by a ref-prefix argument, leading to the tag object
being downloaded, but the ref not being created.
Commit dcc73cf7ff ("fetch: generate ref-prefixes when using a configured
refspec", 2018-05-18) ensured that "refs/tags/" is always sent as a ref
prefix when "git fetch" is invoked with no refspecs, but not when "git
fetch" is invoked with refspecs. Extend that functionality to make it
work in both situations.
This also necessitates a change another test which tested ref
advertisement filtering using tag refs - since tag refs are sent by
default now, the test has been switched to using branch refs instead.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Extend the protocol v2 tests to also test fetches with multiple refspecs
specified. This also covers the previously uncovered cases of fetching
with prefix matching and fetching by SHA-1.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Sometimes I want to remove only Coccinelle's results, but keep all
other build artifacts left after my usual 'make all man' build. This
new 'cocciclean' make target will allow just that.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Coccinelle outputs its suggested transformations as patches, whose
header looks something like this:
--- commit.c
+++ /tmp/cocci-output-19250-7ae78a-commit.c
Note the lack of 'diff --opts <old> <new>' line, the differing number
of path components on the --- and +++ lines, and the nonsensical
filename on the +++ line. 'patch -p0' can still apply these patches,
as it takes the filename to be modified from the --- line. Alas, 'git
apply' can't, because it takes the filename from the +++ line, and
then complains about the nonexisting file.
Pass the '--patch .' options to Coccinelle via the SPATCH_FLAGS 'make'
variable, as it seems to make it generate proper context diff patches,
with the header starting with a 'diff ...' line and containing sane
filenames. The resulting 'contrib/coccinelle/*.cocci.patch' files
then can be applied both with 'git apply' and 'patch' (even without
'-p0').
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
sha1dc is an external library, that we carry in-tree for convenience
or grab as a submodule, so there is no use in applying our semantic
patches to its source files.
Therefore, exclude sha1dc's source files from Coccinelle's static
analysis.
This change also makes the static analysis somewhat faster: presumably
because of the heavy use of repetitive macro declarations, applying
the semantic patches 'array.cocci' and 'swap.cocci' to 'sha1dc/sha1.c'
takes over half a minute each on my machine, which amounts to about a
third of the runtime of applying these two semantic patches to the
whole git source tree.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The dependencies of the 'coccicheck' make target are listed with the
help of the $(patsubst) make function, which in this case doesn't do
any pattern substitution, but only adds the '.patch' suffix.
Use the shorter and more idiomatic $(addsuffix) make function instead.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The 'coccicheck' target doesn't create a file with the same name, so
mark it as .PHONY.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Regression tests are automated tests which try to ensure a specific
behavior. The idea is: if the test case fails, the behavior indicated in
the test case's title regressed.
If a regression test that fails, even occasionally, for any reason other
than to indicate the particular regression(s) it tries to catch, it is
less useful than when it really only fails when there is a bug in the
(non-test) code that needs to be fixed.
In the instance of the test case "submodule update --init --recursive
from subdirectory" of the script t7406-submodule-update.sh, the exact
output of a recursive clone is compared with a pre-generated one. And
this is a racy test because the structure of the submodules only
guarantees a *partial* order. The 'none' and the 'rebasing' submodules
*can* be cloned in any order, which means that a mismatch with the
hard-coded order does not necessarily indicate a bug in the tested code.
See for example:
https://git-for-windows.visualstudio.com/git/_build/results?buildId=14035&view=logs
To prevent such false positives from unnecessarily costing time when
investigating test failures, let's take the exact order of the lines out
of the equation by sorting them before comparing them.
This test script seems not to have any more test cases that try to
verify any specific order in which recursive clones process the
submodules, therefore this is the only test case that is changed in this
manner.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Coccinelle's and in turn 'make coccicheck's exit code only indicates
that Coccinelle managed to finish its analysis without any errors
(e.g. no unknown --options, no missing files, no syntax errors in the
semantic patches, etc.), but it doesn't indicate whether it found any
undesired code patterns to transform or not. To find out the latter,
one has to look closer at 'make coccicheck's standard output and look
for lines like:
SPATCH result: contrib/coccinelle/<something>.cocci.patch
And this only indicates that there is something to transform, but to
see what the suggested transformations are one has to actually look
into those '*.cocci.patch' files.
This makes the automated static analysis build job on Travis CI not
particularly useful, because it neither draws our attention to
Coccinelle's findings, nor shows the actual findings. Consequently,
new topics introducing undesired code patterns graduated to master
on several occasions without anyone noticing.
The only way to draw attention in such an automated setting is to fail
the build job. Therefore, modify the 'ci/run-static-analysis.sh'
build script to check all the resulting '*.cocci.patch' files, and
fail the build job if any of them turns out to be not empty. Include
those files' contents, i.e. Coccinelle's suggested transformations, in
the build job's trace log, so we'll know why it failed.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently the static analysis build job runs Coccinelle using a single
'make' job. Using two parallel jobs cuts down the build job's run
time from around 10-12mins to 6-7mins, sometimes even under 6mins
(there is quite large variation between build job runtimes). More
than two parallel jobs don't seem to bring further runtime benefits.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Most of these are straight forward. GETTEXT_POISON does catch the last
string in cmd_pack_objects(), but since this is --progress output, it's
not supposed to be machine-readable.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many messages will be marked for translation in the following
commits. This commit updates some of them to be more consistent and
reduce diff noise in those commits. Changes are
- keep the first letter of die(), error() and warning() in lowercase
- no full stop in die(), error() or warning() if it's single sentence
messages
- indentation
- some messages are turned to BUG(), or prefixed with "BUG:" and will
not be marked for i18n
- some messages are improved to give more information
- some messages are broken down by sentence to be i18n friendly
(on the same token, combine multiple warning() into one big string)
- the trailing \n is converted to printf_ln if possible, or deleted
if not redundant
- errno_errno() is used instead of explicit strerror()
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Let's start with some background about oe_delta_size() and
oe_set_delta_size(). If you already know, skip the next paragraph.
These two are added in 0aca34e826 (pack-objects: shrink delta_size
field in struct object_entry - 2018-04-14) to help reduce 'struct
object_entry' size. The delta size field in this struct is reduced to
only contain max 1MB. So if any new delta is produced and larger than
1MB, it's dropped because we can't really save such a large size
anywhere. Fallback is provided in case existing packfiles already have
large deltas, then we can retrieve it from the pack.
While this should help small machines repacking large repos without
large deltas (i.e. less memory pressure), dropping large deltas during
the delta selection process could end up with worse pack files. And if
existing packfiles already have >1MB delta and pack-objects is
instructed to not reuse deltas, all of them will be dropped on the
floor, and the resulting pack would be definitely bigger.
There is also a regression in terms of CPU/IO if we have large on-disk
deltas because fallback code needs to parse the pack every time the
delta size is needed and just access to the mmap'd pack data is enough
for extra page faults when memory is under pressure.
Both of these issues were reported on the mailing list. Here's some
numbers for comparison.
Version Pack (MB) MaxRSS(kB) Time (s)
------- --------- ---------- --------
2.17.0 5498 43513628 2494.85
2.18.0 10531 40449596 4168.94
This patch provides a better fallback that is
- cheaper in terms of cpu and io because we won't have to read
existing pack files as much
- better in terms of pack size because the pack heuristics is back to
2.17.0 time, we do not drop large deltas at all
If we encounter any delta (on-disk or created during try_delta phase)
that is larger than the 1MB limit, we stop using delta_size_ field for
this because it can't contain such size anyway. A new array of delta
size is dynamically allocated and can hold all the deltas that 2.17.0
can. This array only contains delta sizes that delta_size_ can't
contain.
With this, we do not have to drop deltas in try_delta() anymore. Of
course the downside is we use slightly more memory, even compared to
2.17.0. But since this is considered an uncommon case, a bit more
memory consumption should not be a problem.
Delta size limit is also raised from 1MB to 16MB to better cover
common case and avoid that extra memory consumption (99.999% deltas in
this reported repo are under 12MB; Jeff noted binary artifacts topped
out at about 3MB in some other private repos). Other fields are
shuffled around to keep this struct packed tight. We don't use more
memory in common case even with this limit update.
A note about thread synchronization. Since this code can be run in
parallel during delta searching phase, we need a mutex. The realloc
part in packlist_alloc() is not protected because it only happens
during the object counting phase, which is always single-threaded.
Access to e->delta_size_ (and by extension
pack->delta_size[e - pack->objects]) is unprotected as before, the
thread scheduler in pack-objects must make sure "e" is never updated
by two different threads.
The area under the new lock is as small as possible, avoiding locking
at all in common case, since lock contention with high thread count
could be expensive (most blobs are small enough that delta compute
time is short and we end up taking the lock very often). The previous
attempt to always hold a lock in oe_delta_size() and
oe_set_delta_size() increases execution time by 33% when repacking
linux.git with with 40 threads.
Reported-by: Elijah Newren <newren@gmail.com>
Helped-by: Elijah Newren <newren@gmail.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When running the same reproduction script as the previous patch,
it turns out the stack is too small, which can be easily avoided.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach clone to send a list of ref-prefixes, when using protocol v2, to
allow the server to filter out irrelevant references from the
ref-advertisement. This reduces wasted time and bandwidth when cloning
repositories with a larger number of references.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The five new tests added to 't9300-fast-import.sh' in 30e215a65c
(fast-import: checkpoint: dump branches/tags/marks even if
object_count==0, 2017-09-28), all with the prefix "V:" in their test
description, run 'git fast-import' in the background and then 'kill'
it as part of a 'test_when_finished' cleanup command. When this test
script is executed with Bash, some or even all of these tests tend to
pollute the test script's stderr, and messages about terminated
processes end up on the terminal:
$ bash ./t9300-fast-import.sh
<... snip ...>
ok 179 - V: checkpoint helper does not get stuck with extra output
/<...>/test-lib-functions.sh: line 388: 28383 Terminated git fast-import $options 0<&8 1>&9
ok 180 - V: checkpoint updates refs after reset
./t9300-fast-import.sh: line 3210: 28401 Terminated git fast-import $options 0<&8 1>&9
ok 181 - V: checkpoint updates refs and marks after commit
ok 182 - V: checkpoint updates refs and marks after commit (no new objects)
./test-lib.sh: line 634: line 3250: 28485 Terminated git fast-import $options 0<&8 1>&9
ok 183 - V: checkpoint updates tags after tag
./t9300-fast-import.sh: line 3264: 28510 Terminated git fast-import $options 0<&8 1>&9
After a background child process terminates, its parent Bash process
always outputs a message like those above to stderr, even when in
non-interactive mode.
But how do some of these messages end up on the test script's stderr,
why don't we get them from all five tests, and why do they come from
different file/line locations? Well, after sending the TERM signal to
the background child process, it takes a little while until that
process receives the signal and terminates, and then it takes another
while until the parent process notices it. During this time the
parent Bash process is continuing execution, and by the time it
notices that its child terminated it might have already left
'test_eval_inner_' and its stderr is not redirected to /dev/null
anymore. That's why such a message can appear on the test script's
stderr, while other times, when the child terminates fast and/or the
parent shell is slow enough, the message ends up in /dev/null, just
like any other output of the test does. Bash always adds the file
name and line number of the code location it was about to execute when
it notices the termination of its child process as a prefix to that
message, hence the varying and sometimes totally unrelated location
prefixes in those messages (e.g. line 388 in 'test-lib-functions.sh'
is 'test_verify_prereq', and I saw such a message pointing to
'say_color' as well).
Prevent these messages from appearing on the test script's stderr by
'wait'-ing on the pid of the background 'git fast-import' process
after sending it the TERM signal. This ensures that the executing
shell's stderr is still redirected when the shell notices the
termination of its child process in the background, and that these
messages get a consistent file/line location prefix.
Note that this is not an issue when the test script is run with Bash
and '-v', because then these messages are supposed to go to the test
script's stderr anyway, and indeed all of them do; though the
sometimes seemingly random file/line prefixes could be confusing
still. Similarly, it's not an issue with Bash and '--verbose-log'
either, because then all messages go to the log file as they should.
Finally, it's not an issue with some other shells (I tried dash, ksh,
ksh93 and mksh) even without any of the verbose options, because they
don't print messages like these in non-interactive mode in the first
place.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add test cases to cover the new X509/gpgsm support. Most of them
resemble existing ones. They just switch the format to x509 and set the
signingkey when creating signatures. Validation of signatures does not
need any configuration of git, it does need gpgsm to be configured to
trust the key(-chain).
Several of the testcases build on top of existing gpg testcases.
The commit ships a self-signed key for committer@example.com and
configures gpgsm to trust it.
Signed-off-by: Henning Schild <henning.schild@siemens.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This fixes a memory issue when recursing a lot, which can be reproduced as
seq 1 100000 >one
seq 1 4 100000 >two
git diff --no-index --histogram one two
Before this patch, histogram_diff would call itself recursively before
calling free_index, which would mean a lot of memory is allocated during
the recursion and only freed afterwards. By moving the memory allocation
(and its free call) into find_lcs, the memory is free'd before we recurse,
such that memory is reused in the next step of the recursion instead of
using new memory.
This addresses only the memory pressure, not the run time complexity,
that is also awful for the corner case outlined above.
Helpful in understanding the code (in addition to the sparse history of
this file), was https://stackoverflow.com/a/32367597 which reproduces
most of the code comments of the JGit implementation.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This will be useful in the next patch as we'll introduce multiple
callers.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
By passing the 'xpp' and 'env' argument directly to the function
'fall_back_to_classic_diff', we eliminate an occurrence of the 'index'
in histogram_diff, which will prove useful in a bit.
While at it, move it up in the file. This will make the diff of
one of the next patches more legible.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The option of --color-moved has proven to be useful as observed on the
mailing list. However when refactoring sometimes the indentation changes,
for example when partitioning a functions into smaller helper functions
the code usually mostly moved around except for a decrease in indentation.
To just review the moved code ignoring the change in indentation, a mode
to ignore spaces in the move detection as implemented in a previous patch
would be enough. However the whole move coloring as motivated in commit
2e2d5ac (diff.c: color moved lines differently, 2017-06-30), brought
up the notion of the reviewer being able to trust the move of a "block".
As there are languages such as python, which depend on proper relative
indentation for the control flow of the program, ignoring any white space
change in a block would not uphold the promises of 2e2d5ac that allows
reviewers to pay less attention to the inside of a block, as inside
the reviewer wants to assume the same program flow.
This new mode of white space ignorance will take this into account and will
only allow the same white space changes per line in each block. This patch
even allows only for the same change at the beginning of the lines.
As this is a white space mode, it is made exclusive to other white space
modes in the move detection.
This patch brings some challenges, related to the detection of blocks.
We need a wide net to catch the possible moved lines, but then need to
narrow down to check if the blocks are still intact. Consider this
example (ignoring block sizes):
- A
- B
- C
+ A
+ B
+ C
At the beginning of a block when checking if there is a counterpart
for A, we have to ignore all space changes. However at the following
lines we have to check if the indent change stayed the same.
Checking if the indentation change did stay the same, is done by computing
the indentation change by the difference in line length, and then assume
the change is only in the beginning of the longer line, the common tail
is the same. That is why the test contains lines like:
- <TAB> A
...
+ A <TAB>
...
As the first line starting a block is caught using a compare function that
ignores white spaces unlike the rest of the block, where the white space
delta is taken into account for the comparison, we also have to think about
the following situation:
- A
- B
- A
- B
+ A
+ B
+ A
+ B
When checking if the first A (both in the + and - lines) is a start of
a block, we have to check all 'A' and record all the white space deltas
such that we can find the example above to be just one block that is
indented.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We can already disable replace refs using a command line
option or environment variable, but those are awkward to
apply universally. Let's add a config option to do the same
thing.
That raises the question of why one might want to do so
universally. The answer is that replace refs violate the
immutability of objects. For instance, if you wanted to
cache the diff between commit XYZ and its parent, then in
theory that never changes; the hash XYZ represents the total
state. But replace refs violate that; pushing up a new ref
may create a completely new diff.
The obvious "if it hurts, don't do it" answer is not to
create replace refs if you're doing this kind of caching.
But for a site hosting arbitrary repositories, they may want
to allow users to share replace refs with each other, but
not actually respect them on the site (because the caching
is more important than the replace feature).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This was added as a NEEDSWORK in c3c36d7de2 (replace-object:
check_replace_refs is safe in multi repo environment, 2018-04-11),
waiting for a calmer period. Since doing so now doesn't conflict
with anything in 'pu', it seems as good a time as any.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit afc711b8e1 (rename read_replace_refs to
check_replace_refs, 2014-02-18) added a comment mentioning
that check_replace_refs is set in two ways:
- from user intent via --no-replace-objects, etc
- after seeing there are no replace refs to respect
Since c3c36d7de2 (replace-object: check_replace_refs is safe
in multi repo environment, 2018-04-11) the second is no
longer true. Let's drop that part of the comment.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
