Sync does some work determining what URLs should be used for a submodule
but then throws this work away if the submodule isn't active. Instead
perform the activity check earlier and skip inactive submodule in order
to avoid doing unnecessary work.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The definition of which submodules are of interest by the user
is tied to the configuration submodule.<name>.url; when it is
set to a non-empty string, it is of interest. We'd want to be
able to later change this definition, but there are many places
that explicitly check this condition in the scripted Porcelain.
Introduce the "is-active" subcommand to "submodule--helper", so
that the exact definition of what submodule is of interest can
be centrally defined (and changed in later steps). In a few
patches that follow, this helper is used to replace the explicit
checks of the configuration variable in scripts.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We used to use the SHA1 implementation from the OpenSSL library by
default. As we are trying to be careful against collision attacks
after the recent "shattered" announcement, switch the default to
encourage people to use DC_SHA1 implementation instead. Those who
want to use the implementation from OpenSSL can explicitly ask for
it by OPENSSL_SHA1=YesPlease when running "make".
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We don't actually have a Git-object collision, so the best
we can do is to run one of the shattered PDFs through
test-sha1. This should trigger the collision check and die.
In a sense this isn't really checking anything that the
upstream sha1collisiondetection project doesn't cover
already. But it at least makes sure that our build correctly
uses the library.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This knob lets you use the sha1dc implementation from:
https://github.com/cr-marcstevens/sha1collisiondetection
which can detect certain types of collision attacks (even
when we only see half of the colliding pair). So it
mitigates any attack which consists of getting the "good"
half of a collision into a trusted repository, and then
later replacing it with the "bad" half. The "good" half is
rejected by the victim's version of Git (and even if they
run an old version of Git, any sha1dc-enabled git will
complain loudly if it ever has to interact with the object).
The big downside is that it's slower than either the openssl
or block-sha1 implementations.
Here are some timings based off of linux.git:
- compute sha1 over whole packfile
sha1dc: 3.580s
blk-sha1: 2.046s (-43%)
openssl: 1.335s (-62%)
- rev-list --all --objects
sha1dc: 33.512s
blk-sha1: 33.514s (+0.0%)
openssl: 33.650s (+0.4%)
- git log --no-merges -10000 -p
sha1dc: 8.124s
blk-sha1: 7.986s (-1.6%)
openssl: 8.203s (+0.9%)
- index-pack --verify
sha1dc: 4m19s
blk-sha1: 2m57s (-32%)
openssl: 2m19s (-42%)
So overall the sha1 computation with collision detection is
about 1.75x slower than block-sha1, and 2.7x slower than
sha1. But of course most operations do more than just sha1.
Normal object access isn't really slowed at all (both the
+/- changes there are well within the run-to-run noise); any
changes are drowned out by the other work Git is doing.
The most-affected operation is `index-pack --verify`, which
is essentially just computing the sha1 on every object. This
is similar to the `index-pack` invocation that the receiver
of a push or fetch would perform. So clearly there's some
extra CPU load here.
There will also be some latency for the user, though keep in
mind that such an operation will generally be network bound
(this is about a 1.2GB packfile). Some of that extra CPU is
"free" in the sense that we use it while the pack is
streaming in anyway. But most of it comes during the
delta-resolution phase, after the whole pack has been
received. So we can imagine that for this (quite large)
push, the user might have to wait an extra 100 seconds over
openssl (which is what we use now). If we assume they can
push to us at 20Mbit/s, that's 480s for a 1.2GB pack, which
is only 20% slower.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Improve readability by using the for_each_string_list_item helper
instead of manually iterating with an integer counter.
Signed-off-by: Stefan Beller <sbeller@google.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since the conversion from shell to C in 56dc3ab04 (sequencer
(rebase -i): implement the 'edit' command, 2017-01-02),
stopping at an "edit" instruction went from:
$ git rebase -i
Stopped at 6ce6b914a... odb_pack_keep(): stop generating keepfile name
You can amend the commit now, with
[...more instructions...]
to:
$ git rebase -i
warning: stopped at 6ce6b914a... odb_pack_keep(): stop generating keepfile name
You can amend the commit now, with
[...more instructions...]
The "warning" implies that it's something unexpected, but
it's not. Let's switch back to the original message.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The safe_hash feature is designed to make sha1dc a drop-in
replacement for sha1, where colliding entries will get a
permuted hash to un-collide them. However, since we're
handling the collision case ourselves, this isn't helpful
(and is actually harmful, as it means you get the wrong
object id if you want to show it in a log message).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We can replace system includes with git-compat-util.h or
cache.h (and should make sure it is included first in all C
files). And we can drop includes from headers entirely, as
every C file should include git-compat-util.h itself.
We will add in new include guards around the header files,
though (otherwise you get into trouble including both
sha1dc/sha1.h and cache.h).
And finally, we'll use the full "sha1dc/" path for including
related files. This isn't strictly necessary, but makes the
expected resolution more obvious.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is pulled straight from:
https://github.com/cr-marcstevens/sha1collisiondetection
with no modifications yet (though I've pulled in only the
subset of files necessary for Git to use).
This is commit 007905a93c973f55b2daed6585f9f6c23545bf66.
Further updates can be done like:
git checkout -b vendor-sha1dc $this_commit
cp /path/to/sha1dc/{LICENSE.txt,lib/*} sha1dc/
git add -A sha1dc
git commit -m "update sha1dc"
git checkout -b update-sha1dc origin
git merge vendor-sha1dc
Thanks to both Marc and Dan for making the code fit our
needs by doing both optimization work, cutting down on the
object size, and doing some syntactic changes to work better
with git. And to Linus for kicking off the "diet" work that
removed some of the unused code.
The license of the sha1dc code is the MIT license, which is
obviously compatible with the GPLv2 of git.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A new known failure mode is introduced[1], which is actually not
a failure but a feature in read-tree. Unlike checkout for which
the recursive submodule tests were originally written, read-tree does
warn about ignored untracked files that would be overwritten.
For the sake of keeping the test library for submodules generic, just
mark the test as a failure.
[1] KNOWN_FAILURE_SUBMODULE_OVERWRITE_IGNORED_UNTRACKED
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This exposes a flag to recurse into submodules
in builtin/checkout making use of the code implemented
in prior patches.
A new failure mode is introduced in the submodule
update library, as the directory/submodule conflict
is not solved in prior patches.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a submodule is introduced with a new revision
we need to create the submodule in the worktree as well.
As 'submodule_move_head' handles edge cases, all we have
to do is call it from within the function that creates
new files in the working tree for workingtree operations.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a later patch we'll support submodule entries to be
in sync with the tree in working tree changing commands,
such as checkout or read-tree.
When a new submodule entry changes in the tree, we need to
check if there are conflicts (directory/file conflicts)
for the tree. Add this check for submodules to be
performed before the working tree is touched.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The check (which uses the old oid) is yet to be implemented, but this part
is just a refactor, so it can go separately first.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In later patches we introduce the options and flag for commands
that modify the working directory, e.g. git-checkout.
This piece of code will be used universally for
all these working tree modifications as it
* supports dry run to answer the question:
"Is it safe to change the submodule to this new state?"
e.g. is it overwriting untracked files or are there local
changes that would be overwritten?
* supports a force flag that can be used for resetting
the tree.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a later patch we need to use the super_prefix, and
in case it is NULL we can just assume it is empty.
Create a helper function for this.
We already have some use cases for this helper function,
convert them, too.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git v2.12 was shipped with an embarrassing breakage where various
operations that verify paths given from the user stopped dying when
seeing an issue, and instead later triggering segfault.
... and then to down to 'maint'.
* js/realpath-pathdup-fix:
real_pathdup(): fix callsites that wanted it to die on error
t1501: demonstrate NULL pointer access with invalid GIT_WORK_TREE
Code clean-up and a string truncation fix.
* mm/two-more-xstrfmt:
bisect_next_all: convert xsnprintf to xstrfmt
stop_progress_msg: convert xsnprintf to xstrfmt
The command-line parsing of "git log -L" copied internal data
structures using incorrect size on ILP32 systems.
* vn/line-log-memcpy-size-fix:
line-log: use COPY_ARRAY to fix mis-sized memcpy
The code to parse "git log -L..." command line was buggy when there
are many ranges specified with -L; overrun of the allocated buffer
has been fixed.
* ax/line-log-range-merge-fix:
line-log.c: prevent crash during union of too many ranges
The patch subcommand of "git add -i" was meant to have paths
selection prompt just like other subcommand, unlike "git add -p"
directly jumps to hunk selection. Recently, this was broken and
"add -i" lost the paths selection dialog, but it now has been
fixed.
* jk/add-i-patch-do-prompt:
add--interactive: fix missing file prompt for patch mode with "-i"
When a redirected http transport gets an error during the
redirected request, we ignored the error we got from the server,
and ended up giving a not-so-useful error message.
* jt/http-base-url-update-upon-redirect:
http: attempt updating base URL only if no error
Reduce authentication round-trip over HTTP when the server supports
just a single authentication method.
* jk/http-auth:
http: add an "auto" mode for http.emptyauth
http: restrict auth methods to what the server advertises
The final() function accepts a NULL value for certain
parameters, and falls back to writing into a reusable "name"
buffer, and then either:
1. For "keep_name", requiring all uses to do "keep_name ?
keep_name : name.buf". This is awkward, and it's easy
to accidentally look at the maybe-NULL keep_name.
2. For "final_index_name" and "final_pack_name", aliasing
those pointers to the "name" buffer. This is easier to
use, but the aliased pointers become invalid after the
buffer is reused (this isn't a bug now, but it's a
potential pitfall).
One way to make this safer would be to introduce an extra
pointer to do the aliasing, and have its lifetime match the
validity of the "name" buffer. But it's still easy to
accidentally use the wrong name (i.e., to use
"final_pack_name" instead of the aliased pointer).
Instead, let's use three separate buffers that will remain
valid through the function. That makes it safe to alias the
pointers and use them consistently. The extra allocations
shouldn't matter, as this function is not performance
sensitive.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In several places we write the name of the pack filename
into a fixed-size buffer using snprintf(), but do not check
the return value. As a result, a very long object directory
could cause us to quietly truncate the pack filename
(potentially leading to a corrupted repository, as a newly
written packfile could be missing its .pack extension).
We can use odb_pack_name() to do this with a strbuf (and
shorten the code, as well).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The odb_pack_keep() function generates the name of a .keep
file and opens it. This has two problems:
1. It requires a fixed-size buffer to create the filename
and doesn't notice when the result is truncated.
2. Of the two callers, one sometimes wants to open a
filename it already has, which makes things awkward (it
has to do so manually, and skips the leading-directory
creation).
Instead, let's have odb_pack_keep() just open the file.
Generating the name isn't hard, and a future patch will
switch callers over to odb_pack_name() anyway.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We provide sha1_pack_name() and sha1_pack_index_name(), but
the more generic form (which takes its own strbuf and an
arbitrary extension) is only used to implement the other
two. Let's make it available, but clean up a few things:
1. Name it odb_pack_name(), as the original
sha1_get_pack_name() is long but not all that
descriptive.
2. Switch the strbuf argument to the beginning, so that it
matches similar path-building functions like
git_path_buf().
3. Clean up the out-dated docstring and move it to the
public declaration.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These functions were originally conceived as wrapper
functions similar to xmkstemp(). They were later moved by
463db9b10 (wrapper: move odb_* to environment.c,
2010-11-06). The more appropriate place for a declaration is
in cache.h.
While we're at it, let's add some basic docstrings.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a later patch we need to prepare the submodule environment with
another git directory, so split up the function.
Also move it up in the file such that we do not need to declare the
function later before using it.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In later patches we introduce the --recurse-submodule flag for commands
that modify the working directory, e.g. git-checkout.
It is potentially expensive to check if a submodule needs an update,
because a common theme to interact with submodules is to spawn a child
process for each interaction.
So let's introduce a function that checks if a submodule needs
to be checked for an update before attempting the update.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In later patches we introduce the options and flag for commands
that modify the working directory, e.g. git-checkout.
Have a central place to store such settings whether we want to update
a submodule.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Similar to b33a15b08 (push: add recurseSubmodules config option,
2015-11-17) and 027771fcb1 (submodule: allow erroneous values for the
fetchRecurseSubmodules option, 2015-08-17), we add submodule-config code
that is later used to parse whether we are interested in updating
submodules.
We need the `die_on_error` parameter to be able to call this parsing
function for the config file as well, which if incorrect lets Git die.
As we're just touching the header file, also mark all functions extern.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We need the gentle version in a later patch. As we have just one caller,
migrate the caller.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently lib-submodule-update.sh provides 2 functions
test_submodule_switch and test_submodule_forced_switch that are used by a
variety of tests to ensure that submodules behave as expected. The current
expected behavior is that submodules are not touched at all (see
42639d2317 for the exact setup).
In the future we want to teach all these commands to recurse
into submodules. To do that, we'll add two testing functions to
submodule-update-lib.sh: test_submodule_switch_recursing and
test_submodule_forced_switch_recursing.
These two functions behave in analogy to the already existing functions
just with a different expectation on submodule behavior. The submodule
in the working tree is expected to be updated to the recorded submodule
version. The behavior is analogous to e.g. the behavior of files in a
nested directory in the working tree, where a change to the working tree
handles any arising directory/file conflicts just fine.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Cleaning up code by generalising it.
Currently the mailing list discusses yet again how
to migrate away from sha1.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Adding the repository itself as a submodule does not make sense in the
real world. In our test suite we used to do that out of convenience in
some tests as the current repository has easiest access for setting up
'just a submodule'.
However this doesn't quite test the real world, so let's do not follow
this pattern any further and actually create an independent repository
that we can use as a submodule.
When using './.' as the remote the superproject and submodule share the
same objects, such that testing if a given sha1 is a valid commit works
in either repository. As running commands in an unpopulated submodule
fall back to the superproject, this happens in `reset_work_tree_to`
to determine if we need to populate the submodule. Fix this bug by
checking in the actual remote now.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Redraw the ASCII art describing the setup using more space, such that
it is easier to understand. The leaf commits are now ordered the same
way the actual code is ordered.
Add empty lines to the setup code separating each of the leaf commits,
each starting with a "checkout -b".
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remove code fragment from module_clone that duplicates functionality
of connect_work_tree_and_git_dir in dir.c
Signed-off-by: Valery Tolstov <me@vtolstov.org>
Reviewed-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a later patch we'll use connect_work_tree_and_git_dir when the
directory for the gitlink file doesn't exist yet. This patch makes
connect_work_tree_and_git_dir safe to use for both cases of
either the git dir or the working dir missing.
To do so, we need to call safe_create_leading_directories[_const]
on both directories. However this has to happen before we construct
the absolute paths as real_pathdup assumes the directories to
be there already.
So for both the config file in the git dir as well as the .git link
file we need to
a) construct the name
b) call SCLD
c) get the absolute path
d) once a-c is done for both we can consume the absolute path
to compute the relative path to each other and store those
relative paths.
The implementation provided here puts a) and b) for both cases first,
and then performs c and d after.
One of the two users of 'connect_work_tree_and_git_dir' already checked
for the directory being there, so we can loose that check as
connect_work_tree_and_git_dir handles this functionality now.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
All of these options do the same thing "--foo" iterates over
the "foo" refs, and "--foo=<glob>" does the same with a
glob. We can factor this into its own function to avoid
repeating ourselves.
There are two subtleties to note:
- the original called for_each_branch_ref(), etc, in the
non-glob case. Now we will call for_each_ref_in("refs/heads/")
which is exactly what for_each_branch_ref() did under
the hood.
- for --glob, we'll call for_each_glob_ref_in() with a
NULL "prefix" argument. Which is exactly what
for_each_glob_ref() was doing already.
So both cases should behave identically, and it seems
reasonable to assume that this will remain the same. The
functions we are calling now are the more-generic ones, and
the ones we are dropping are just convenience wrappers.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We can't just use a bare skip_prefix() for these cases,
because we need to match both the "--foo" form and the
"--foo=<value>" form (and tell the difference between the
two in the caller).
We can wrap this in a simple helper which has two obvious
callsites, and will gain some more in the next patch.
Note that the error output for abbrev-ref changes slightly,
as we don't keep our original "arg" pointer. However, the
new output should hopefully be more clear:
[before]
fatal: unknown mode for --abbrev-ref=foo
[after]
fatal: unknown mode for --abbrev-ref: foo
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Using skip_prefix lets us avoid manually-counted offsets
into the argument string. This patch converts the simple and
obvious cases.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
