When opening a MIDX/pack-bitmap, we call open_midx_bitmap_1() or
open_pack_bitmap_1() respectively in a loop over the set of MIDXs/packs.
By design, these functions are supposed to be called over every pack and
MIDX, since only one of them should have a valid bitmap.
Ordinarily we return '0' from these two functions in order to indicate
that we successfully loaded a bitmap To signal that we couldn't load a
bitmap corresponding to the MIDX/pack (either because one doesn't exist,
or because there was an error with loading it), we can return '-1'. In
either case, the callers each enumerate all MIDXs/packs to ensure that
at most one bitmap per-kind is present.
But when we fail to load a bitmap that does exist (for example, loading
a MIDX bitmap without finding a corresponding reverse index), we'll
return -1 but leave the 'midx' field non-NULL. So when we fallback to
loading a pack bitmap, we'll complain that the bitmap we're trying to
populate already is "opened", even though it isn't.
Rectify this by setting the '->pack' and '->midx' field back to NULL as
appropriate. Two tests are added: one to ensure that the MIDX-to-pack
bitmap fallback works, and another to ensure we still complain when
there are multiple pack bitmaps in a repository.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a MIDX contains the new `RIDX` chunk, ensure that the reverse index
is read from it instead of the on-disk .rev file. Since we need to
encode the object order in the MIDX itself for correctness reasons,
there is no point in storing the same data again outside of the MIDX.
So, this patch stops writing separate .rev files, and reads it out of
the MIDX itself. This is possible to do with relatively little new code,
since the format of the RIDX chunk is identical to the data in the .rev
file. In other words, we can implement this by pointing the
`revindex_data` field at the reverse index chunk of the MIDX instead of
the .rev file without any other changes.
Note that we have two knobs that are adjusted for the new tests:
GIT_TEST_MIDX_WRITE_REV and GIT_TEST_MIDX_READ_RIDX. The former controls
whether the MIDX .rev is written at all, and the latter controls whether
we read the MIDX's RIDX chunk.
Both are necessary to ensure that the test added at the beginning of
this series continues to work. This is because we always need to write
the RIDX chunk in the MIDX in order to change its checksum, but we want
to make sure reading the existing .rev file still works (since the RIDX
chunk takes precedence by default).
Arguably this isn't a very interesting mode to test, because the
precedence rules mean that we'll always read the RIDX chunk over the
.rev file. But it makes it impossible for a user to induce corruption in
their repository by adjusting the test knobs (since if we had an
either/or knob they could stop writing the RIDX chunk, allowing them to
tweak the MIDX's object order without changing its checksum).
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To prepare for reading the reverse index data out of the MIDX itself,
teach the `test_rev_exists` function to take an expected "source" for
the reverse index data.
When given "rev", it asserts that the MIDX's `.rev` file exists, and is
loaded when verifying the integrity of its bitmaps. Otherwise, it
ensures that trace2 reports the source of the reverse index data as the
same string which was given to test_rev_exists().
The following patch will implement reading the reverse index data from
the MIDX itself.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In t5326, we have a handful of tests that we would like to run twice:
once using the MIDX's new `RIDX` chunk as the source of the
reverse-index cache, and once using the separate `.rev` file.
But because these tests mutate the state of the underlying repository,
and then make assumptions about those mutations occurring in a certain
sequence, simply running the tests twice in the same repository is
awkward.
Instead, extract the core of interesting tests into t/lib-bitmap.sh to
prepare for them to be run twice, each in a separate test script. This
means that they can each operate on a separate repository, removing any
concerns about mutating state.
For now, this patch is a strict cut-and-paste of some tests from t5326.
The tests which did not move are not interesting with respect to the
source of their reverse index data.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To determine which source of data is used for the MIDX's reverse index
cache, introduce a helper which forces loading the reverse index, and
then looks for the special trace2 event introduced in a previous commit.
For now, this helper just looks for when the legacy MIDX .rev file was
loaded, but in a subsequent commit will become parameterized over the
the reverse index's source.
This function replaces checking for the existence of the .rev file. We
could write a similar helper to ensure that the .rev file is cleaned up
after repacking, but it will make subsequent tests more difficult to
write, and provides marginal value since we already check that the MIDX
.bitmap file is removed.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The core.multiPackIndex config became true by default back in 18e449f86b
(midx: enable core.multiPackIndex by default, 2020-09-25), so it is no
longer necessary to enable it explicitly.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a subsequent commit, we'll use the MIDX's new 'RIDX' chunk as a
source for the reverse index's data. But it will be useful for tests to
be able to determine whether the reverse index was loaded from the
separate .rev file, or from a chunk within the MIDX.
To instrument this, add a trace2 event which the tests can look for in
order to determine the reverse index's source.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The previous patch demonstrates a bug where a MIDX's auxiliary object
order can become out of sync with a MIDX bitmap.
This is because of two confounding factors:
- First, the object order is stored in a file which is named according
to the multi-pack index's checksum, and the MIDX does not store the
object order. This means that the object order can change without
altering the checksum.
- But the .rev file is moved into place with finalize_object_file(),
which link(2)'s the file into place instead of renaming it. For us,
that means that a modified .rev file will not be moved into place if
MIDX's checksum was unchanged.
This fix is to force the MIDX's checksum to change when the preferred
pack changes but the set of packs contained in the MIDX does not. In
other words, when the object order changes, the MIDX's checksum needs to
change with it (regardless of whether the MIDX is tracking the same or
different packs).
This prevents a race whereby changing the object order (but not the
packs themselves) enables a reader to see the new .rev file with the old
MIDX, or similarly seeing the new bitmap with the old object order.
But why can't we just stop hardlinking the .rev into place instead
adding additional data to the MIDX? Suppose that's what we did. Then
when we go to generate the new bitmap, we'll load the old MIDX bitmap,
along with the MIDX that it references. That's fine, since the new MIDX
isn't moved into place until after the new bitmap is generated. But the
new object order *has* been moved into place. So we'll read the old
bitmaps in the new order when generating the new bitmap file, meaning
that without this secondary change, bitmap generation itself would
become a victim of the race described here.
This can all be prevented by forcing the MIDX's checksum to change when
the object order does. By embedding the entire object order into the
MIDX, we do just that. That is, the MIDX's checksum will change in
response to any perturbation of the underlying object order. In t5326,
this will cause the MIDX's checksum to update (even without changing the
set of packs in the MIDX), preventing the stale read problem.
Note that this makes it safe to continue to link(2) the MIDX .rev file
into place, since it is now impossible to have a .rev file that is
out-of-sync with the MIDX whose checksum it references. (But we will do
away with MIDX .rev files later in this series anyway, so this is
somewhat of a moot point).
In theory, it is possible to store a "fingerprint" of the full object
order here, so long as that fingerprint changes at least as often as the
full object order does. Some possibilities here include storing the
identity of the preferred pack, along with the mtimes of the
non-preferred packs in a consistent order. But storing a limited part of
the information makes it difficult to reason about whether or not there
are gaps between the two that would cause us to get bitten by this bug
again.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This patch demonstrates a cause of bitmap corruption that can occur when
the contents of the multi-pack index does not change, but the underlying
object order does.
In this example, we have a MIDX containing two packs, each with a
distinct set of objects (pack A corresponds to the tree, blob, and
commit from the first patch, and pack B corresponds to the second
patch).
First, a MIDX is written where the 'A' pack is preferred. As expected,
the bitmaps generated there are in-tact. But then, we generate an
identical MIDX with a different object order: this time preferring pack
'B'.
Due to a bug which will be explained and fixed in the following commit,
the MIDX is updated, but the .rev file is not, causing the .bitmap file
to be read incorrectly. Specifically, the .bitmap file will contain
correct data, but the auxiliary object order in the .rev file is stale,
causing readers to get confused by reading the new bitmaps using the old
object order.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "init" and "set" subcommands in "git sparse-checkout" have been
unified for a better user experience and performance.
* en/sparse-checkout-set:
sparse-checkout: remove stray trailing space
clone: avoid using deprecated `sparse-checkout init`
Documentation: clarify/correct a few sparsity related statements
git-sparse-checkout.txt: update to document init/set/reapply changes
sparse-checkout: enable reapply to take --[no-]{cone,sparse-index}
sparse-checkout: enable `set` to initialize sparse-checkout mode
sparse-checkout: split out code for tweaking settings config
sparse-checkout: disallow --no-stdin as an argument to set
sparse-checkout: add sanity-checks on initial sparsity state
sparse-checkout: break apart functions for sparse_checkout_(set|add)
sparse-checkout: pass use_stdin as a parameter instead of as a global
Broken &&-chains in the test scripts have been corrected.
* es/test-chain-lint:
t6000-t9999: detect and signal failure within loop
t5000-t5999: detect and signal failure within loop
t4000-t4999: detect and signal failure within loop
t0000-t3999: detect and signal failure within loop
tests: simplify by dropping unnecessary `for` loops
tests: apply modern idiom for exiting loop upon failure
tests: apply modern idiom for signaling test failure
tests: fix broken &&-chains in `{...}` groups
tests: fix broken &&-chains in `$(...)` command substitutions
tests: fix broken &&-chains in compound statements
tests: use test_write_lines() to generate line-oriented output
tests: simplify construction of large blocks of text
t9107: use shell parameter expansion to avoid breaking &&-chain
t6300: make `%(raw:size) --shell` test more robust
t5516: drop unnecessary subshell and command invocation
t4202: clarify intent by creating expected content less cleverly
t1020: avoid aborting entire test script when one test fails
t1010: fix unnoticed failure on Windows
t/lib-pager: use sane_unset() to avoid breaking &&-chain
New interface into the tmp-objdir API to help in-core use of the
quarantine feature.
* ns/tmp-objdir:
tmp-objdir: disable ref updates when replacing the primary odb
tmp-objdir: new API for creating temporary writable databases
"git format-patch" uses a single rev_info instance and then exits.
Mark the structure with UNLEAK() macro to squelch leak sanitizer.
* jc/unleak-log:
format-patch: mark rev_info with UNLEAK
The chainlint test script linter in the test suite has been updated.
* es/chainlint:
chainlint.sed: stop splitting "(..." into separate lines "(" and "..."
chainlint.sed: swallow comments consistently
chainlint.sed: stop throwing away here-doc tags
chainlint.sed: don't mistake `<< word` in string as here-doc operator
chainlint.sed: make here-doc "<<-" operator recognition more POSIX-like
chainlint.sed: drop subshell-closing ">" annotation
chainlint.sed: drop unnecessary distinction between ?!AMP?! and ?!SEMI?!
chainlint.sed: tolerate harmless ";" at end of last line in block
chainlint.sed: improve ?!SEMI?! placement accuracy
chainlint.sed: improve ?!AMP?! placement accuracy
t/Makefile: optimize chainlint self-test
t/chainlint/one-liner: avoid overly intimate chainlint.sed knowledge
t/chainlint/*.test: generalize self-test commentary
t/chainlint/*.test: fix invalid test cases due to mixing quote types
t/chainlint/*.test: don't use invalid shell syntax
"git apply" has been taught to ignore a message without a patch
with the "--allow-empty" option. It also learned to honor the
"--quiet" option given from the command line.
* jz/apply-quiet-and-allow-empty:
git-apply: add --allow-empty flag
git-apply: add --quiet flag
"git fetch --set-upstream" did not check if there is a current
branch, leading to a segfault when it is run on a detached HEAD,
which has been corrected.
* ab/fetch-set-upstream-while-detached:
pull, fetch: fix segfault in --set-upstream option
Add pieces from "scalar" to contrib/.
* js/scalar:
scalar: implement the `version` command
scalar: implement the `delete` command
scalar: teach 'reconfigure' to optionally handle all registered enlistments
scalar: allow reconfiguring an existing enlistment
scalar: implement the `run` command
scalar: teach 'clone' to support the --single-branch option
scalar: implement the `clone` subcommand
scalar: implement 'scalar list'
scalar: let 'unregister' handle a deleted enlistment directory gracefully
scalar: 'unregister' stops background maintenance
scalar: 'register' sets recommended config and starts maintenance
scalar: create test infrastructure
scalar: start documenting the command
scalar: create a rudimentary executable
scalar: add a README with a roadmap
Teach diff and blame to work well with sparse index.
* ld/sparse-diff-blame:
blame: enable and test the sparse index
diff: enable and test the sparse index
diff: replace --staged with --cached in t1092 tests
repo-settings: prepare_repo_settings only in git repos
test-read-cache: set up repo after git directory
commit-graph: return if there is no git directory
git: ensure correct git directory setup with -h
"git name-rev" has been tweaked to give output that is shorter and
easier to understand.
* en/name-rev-shorter-output:
name-rev: prefer shorter names over following merges
"git fetch" without the "--update-head-ok" option ought to protect
a checked out branch from getting updated, to prevent the working
tree that checks it out to go out of sync. The code was written
before the use of "git worktree" got widespread, and only checked
the branch that was checked out in the current worktree, which has
been updated.
(originally called ak/fetch-not-overwrite-any-current-branch)
* ak/protect-any-current-branch:
branch: protect branches checked out in all worktrees
receive-pack: protect current branch for bare repository worktree
receive-pack: clean dead code from update_worktree()
fetch: protect branches checked out in all worktrees
worktree: simplify find_shared_symref() memory ownership model
branch: lowercase error messages
receive-pack: lowercase error messages
fetch: lowercase error messages
The cryptographic signing using ssh keys can specify literal keys
for keytypes whose name do not begin with the "ssh-" prefix by
using the "key::" prefix mechanism (e.g. "key::ecdsa-sha2-nistp256").
* fs/ssh-signing-other-keytypes:
ssh signing: make sign/amend test more resilient
ssh signing: support non ssh-* keytypes
Extend the signing of objects with SSH keys and learn to pay
attention to the key validity time range when verifying.
* fs/ssh-signing-key-lifetime:
ssh signing: verify ssh-keygen in test prereq
ssh signing: make fmt-merge-msg consider key lifetime
ssh signing: make verify-tag consider key lifetime
ssh signing: make git log verify key lifetime
ssh signing: make verify-commit consider key lifetime
ssh signing: add key lifetime test prereqs
ssh signing: use sigc struct to pass payload
t/fmt-merge-msg: make gpgssh tests more specific
t/fmt-merge-msg: do not redirect stderr
When "git log" implicitly enabled the "decoration" processing
without being explicitly asked with "--decorate" option, it failed
to read and honor the settings given by the "--decorate-refs"
option.
* jk/log-decorate-opts-with-implicit-decorate:
log: load decorations with --simplify-by-decoration
log: handle --decorate-refs with userformat "%d"
"git rebase -x" by mistake started exporting the GIT_DIR and
GIT_WORK_TREE environment variables when the command was rewritten
in C, which has been corrected.
* en/rebase-x-wo-git-dir-env:
sequencer: do not export GIT_DIR and GIT_WORK_TREE for 'exec'
Weather balloon to find compilers that do not grok variable
declaration in the for() loop.
* jc/c99-var-decl-in-for-loop:
revision: use C99 declaration of variable in for() loop
The comand uses a single instance of rev_info on stack, makes a
single revision traversal and exit. Mark the resources held by the
rev_info structure with UNLEAK().
We do not do this at lower level in revision.c or cmd_log_walk(), as
a new caller of the revision traversal API can make unbounded number
of rev_info during a single run, and UNLEAK() would not a be
suitable mechanism to deal with such a caller.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The previous commits marked `sparse-checkout init` as deprecated; we
can just use `set` instead here and pass it no paths.
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Victoria Dye <vdye@github.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As noted in the previous commit, using separate `init` and `set` steps
with sparse-checkout result in a number of issues. The previous commits
made `set` able to handle the work of both commands, and enabled reapply
to tweak the {cone,sparse-index} settings. Update the documentation to
reflect this, and mark `init` as deprecated.
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Victoria Dye <vdye@github.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Folks may want to switch to or from cone mode, or to or from a
sparse-index without changing their sparsity paths. Allow them to do so
using the reapply command.
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Victoria Dye <vdye@github.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The previously suggested workflow:
git sparse-checkout init ...
git sparse-checkout set ...
Suffered from three problems:
1) It would delete nearly all files in the first step, then
restore them in the second. That was poor performance and
forced unnecessary rebuilds.
2) The two-step process resulted in two progress bars, which
was suboptimal from a UI point of view for wrappers that
invoked both of these commands but only exposed a single
command to their end users.
3) With cone mode, the first step would delete nearly all
ignored files everywhere, because everything was considered
to be outside of the specified sparsity paths. (The user was
not allowed to specify any sparsity paths in the `init` step.)
Avoid these problems by teaching `set` to understand the extra
parameters that `init` takes and performing any necessary initialization
if not already in a sparse checkout.
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Victoria Dye <vdye@github.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
`init` has some code for handling updates to either cone mode or
the sparse-index setting. We would like to be able to reuse this
elsewhere, namely in `set` and `reapply`. Split this function out,
and make it slightly more general so it can handle being called from
the new callers.
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Victoria Dye <vdye@github.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We intentionally added --stdin as an option to `sparse-checkout set`,
but didn't intend for --no-stdin to be permitted as well.
Reported-by: Victoria Dye <vdye@github.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Victoria Dye <vdye@github.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Most sparse-checkout subcommands (list, add, reapply) only make sense
when already in a sparse state. Add a quick check that will error out
early if this is not the case.
Also document with a comment why we do not exit early in `disable` even
when core.sparseCheckout starts as false.
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Victoria Dye <vdye@github.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
sparse_checkout_set() was reused by sparse_checkout_add() with the only
difference being a single parameter being passed to that function.
However, we would like sparse_checkout_set() to do the same work that
sparse_checkout_init() does if sparse checkouts are not already enabled.
To facilitate this transition, give each mode their own copy of the
function. This does not introduce any behavioral changes; that will
come in a subsequent patch.
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Victoria Dye <vdye@github.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
add_patterns_from_input() has relied on a global variable,
set_opts.use_stdin, which has been used by both the `set` and `add`
subcommands of sparse-checkout. Once we introduce an
add_opts.use_stdin, the hardcoding of set_opts.use_stdin will be
incorrect. Pass the value as function parameter instead to allow us to
make subsequent changes.
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Victoria Dye <vdye@github.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Code clean-up.
* ab/die-with-bug:
object.c: use BUG(...) no die("BUG: ...") in lookup_object_by_type()
pathspec: use BUG(...) not die("BUG:%s:%d....", <file>, <line>)
strbuf.h: use BUG(...) not die("BUG: ...")
pack-objects: use BUG(...) not die("BUG: ...")
The test helper for refs subsystem learned to write bogus and/or
nonexistent object name to refs to simulate error situations we
want to test Git in.
* hn/allow-bogus-oid-in-ref-tests:
t1430: create valid symrefs using test-helper
t1430: remove refs using test-tool
refs: introduce REF_SKIP_REFNAME_VERIFICATION flag
refs: introduce REF_SKIP_OID_VERIFICATION flag
refs: update comment.
test-ref-store: plug memory leak in cmd_delete_refs
test-ref-store: parse symbolic flag constants
test-ref-store: remove force-create argument for create-reflog
Change the type of an internal function to return an enum (instead
of int) and replace -2 that was used to signal an error with -1.
* ab/parse-options-cleanup:
parse-options.c: use "enum parse_opt_result" for parse_nodash_opt()
"default" and "reset" colors have been added to our palette.
* re/color-default-reset:
color: allow colors to be prefixed with "reset"
color: support "default" to restore fg/bg color
color: add missing GIT_COLOR_* white/black constants
Document the parameters given to the reflog entry iterator callback
functions.
* jc/reflog-iterator-callback-doc:
refs: document callback for reflog-ent iterators
