We switch to using the run-command API function that takes a
'struct child process', since we are using a lot of the options. This
will also make it simple to switch over to using 'capture_command()'
when we start handling the output of the command completely in C.
Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Shourya Shukla <periperidip@gmail.com>
Signed-off-by: Atharva Raykar <raykar.ath@gmail.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* gc/submodule-update-part1:
submodule--helper update-clone: check for --filter and --init
submodule update: add tests for --filter
submodule--helper: remove ensure-core-worktree
submodule--helper update-clone: learn --init
submodule--helper: allow setting superprefix for init_submodule()
submodule--helper: refactor get_submodule_displaypath()
submodule--helper run-update-procedure: learn --remote
submodule--helper: don't use bitfield indirection for parse_options()
submodule--helper: get remote names from any repository
submodule--helper run-update-procedure: remove --suboid
submodule--helper: reorganize code for sh to C conversion
submodule--helper: remove update-module-mode
submodule tests: test for init and update failure output
If the user suspends git while it is waiting for a keypress reset the
terminal before stopping and restore the settings when git resumes. If
the user tries to resume in the background print an error
message (taking care to use async safe functions) before stopping
again. Ideally we would reprint the prompt for the user when git
resumes but this patch just restarts the read().
The signal handler is established with sigaction() rather than using
sigchain_push() as this allows us to control the signal mask when the
handler is invoked and ensure SA_RESTART is used to restart the
read() when resuming.
Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
On macos the builtin "add -p" does not handle keys that generate
escape sequences because poll() does not work with terminals
there. Switch to using select() on non-windows platforms to work
around this.
Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
read_key_without_echo() reads from stdin but uses /dev/tty when it
disables echo. This is unfortunate as there no guarantee that stdin is
the same device as /dev/tty. The perl version of "add -p" uses stdin
when it sets the terminal mode, this commit does the same for the
builtin version. There is still a difference between the perl and
builtin versions though - the perl version will ignore any errors when
setting the terminal mode[1] and will still read single bytes when
stdin is not a terminal. The builtin version displays a warning if
setting the terminal mode fails and switches to reading a line at a
time.
[1] b061c913bb/ReadKey.xs (L1090)
Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The next commit will add another flag in addition to the existing
full_duplex so change the function signature to take a flags
argument. Also alter the functions that call save_term() so that they
can pass flags down to it.
The choice to use an enum for tho bitwise flags is because gdb will
display the symbolic names of all the flags that are set rather than
the integer value.
Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a blobless-cloned repo, `git log --follow -- <path>` (`<path>` have
an exact OID rename) shouldn't download blob of the file from where the
new file is renamed.
Add a test case to verify it.
Signed-off-by: Abhradeep Chakraborty <chakrabortyabhradeep79@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Instead of creating a new allocation, reverse the original list
in-place by calling the reverse_commit_list() helper.
The original code discards the list "bases" after storing its
reverse copy in a newly created list "reversed". If the code that
followed from here used both "bases" and "reversed", the
modification would not have worked, but since the original list
"bases" gets discarded, we can simply reverse "bases" in-place with
the reverse_commit_list() helper and reuse the same variable in the
code that follows.
builtin/merge.c has been left unmodified, since in its case, the
original list is needed separately from its reverse copy by the
code.
Signed-off-by: Jayati Shrivastava <gaurijove@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If no --args are present after 'git restore', it assumes that you
want to tab-complete one of the files with unstaged uncommitted
changes.
If a file has been staged, we don't want to list it, as restoring those
requires a slightly more complex `git restore --staged`, so we only list
those files that are --modified. While --committable also looks like
a good candidate, that includes changes that have been staged.
Signed-off-by: David Cantrell <david@cantrell.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When writing both loose and packed references to disk we first create a
lockfile, write the updated values into that lockfile, and on commit we
rename the file into place. According to filesystem developers, this
behaviour is broken because applications should always sync data to disk
before doing the final rename to ensure data consistency [1][2][3]. If
applications fail to do this correctly, a hard crash of the machine can
easily result in corrupted on-disk data.
This kind of corruption can in fact be easily observed with Git when the
machine hard-resets shortly after writing references to disk. On
machines with ext4, this will likely lead to the "empty files" problem:
the file has been renamed, but its data has not been synced to disk. The
result is that the reference is corrupt, and in the worst case this can
lead to data loss.
Implement a new option to harden references so that users and admins can
avoid this scenario by syncing locked loose and packed references to
disk before we rename them into place.
[1]: https://thunk.org/tytso/blog/2009/03/15/dont-fear-the-fsync/
[2]: https://btrfs.wiki.kernel.org/index.php/FAQ (What are the crash guarantees of overwrite-by-rename)
[3]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/admin-guide/ext4.rst (see auto_da_alloc)
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* ns/core-fsyncmethod:
core.fsync: documentation and user-friendly aggregate options
core.fsync: new option to harden the index
core.fsync: add configuration parsing
core.fsync: introduce granular fsync control infrastructure
core.fsyncmethod: add writeout-only mode
wrapper: make inclusion of Windows csprng header tightly scoped
This commit adds aggregate options for the core.fsync setting that are
more user-friendly. These options are specified in terms of 'levels of
safety', indicating which Git operations are considered to be sync
points for durability.
The new documentation is also included here in its entirety for ease of
review.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The synopsis for 'git maintenance' did not include the commands other
than the 'run' command. Update this to include the others. The 'start'
command is the only one of these that parses additional options, and
then only the --scheduler option.
Also move the 'register' command down after 'stop' and before
'unregister' for a logical grouping of the commands instead of an
alphabetical one. The diff makes it look as three other commands are
moved up.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When format is passed into --batch, --batch-check, --batch-command,
the format gets expanded. When nothing is passed in, the default format
is set and the expand_format() gets called.
We can save on these cycles by hardcoding how to print the
information when nothing is passed as the format, or when the default
format is passed. There is no need for the fully expanded format with
the default. Since batch_object_write() happens on every object provided
in batch mode, we get a nice performance improvement.
git rev-list --all > /tmp/all-obj.txt
git cat-file --batch-check </tmp/all-obj.txt
with HEAD^:
Time (mean ± σ): 57.6 ms ± 1.7 ms [User: 51.5 ms, System: 6.2 ms]
Range (min … max): 54.6 ms … 64.7 ms 50 runs
with HEAD:
Time (mean ± σ): 49.8 ms ± 1.7 ms [User: 42.6 ms, System: 7.3 ms]
Range (min … max): 46.9 ms … 55.9 ms 56 runs
If nothing is provided as a format argument, or if the default format is
passed, skip expanding of the format and print the object info with a
default format.
See https://lore.kernel.org/git/87eecf8ork.fsf@evledraar.gmail.com/
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: John Cai <johncai86@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add the options '-q' and '--refresh' to the 'git reset' executed in
'reset_head()', and '--refresh' to the 'git reset -q' executed in
'do_push_stash(...)'.
'stash' is implemented such that git commands invoked as part of it (e.g.,
'clean', 'read-tree', 'reset', etc.) have their informational output
silenced. However, the 'reset' in 'reset_head()' is *not* called with '-q',
leading to the potential for a misleading printout from 'git stash apply
--index' if the stash included a removed file:
Unstaged changes after reset: D <deleted file>
Not only is this confusing in its own right (since, after the reset, 'git
stash' execution would stage the deletion in the index), it would be printed
even when the stash was applied with the '-q' option. As a result, the
messaging is removed entirely by calling 'git status' with '-q'.
Additionally, because the default behavior of 'git reset -q' is to skip
refreshing the index, but later operations in 'git stash' subcommands expect
a non-stale index, enable '--refresh' as well.
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If using '--quiet' or 'reset.quiet=true', do not print the 'resetnoRefresh'
advice string. For applications that rely on '--quiet' disabling all
non-error logs, the advice message should be suppressed accordingly.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Replace references to '--quiet' with '--no-refresh' in the advice on how to
skip refreshing the index. When the advice was introduced, '--quiet' was the
only way to avoid the expensive 'refresh_index(...)' at the end of a mixed
reset. After introducing '--no-refresh', however, '--quiet' became only a
fallback option for determining refresh behavior, overridden by
'--[no-]refresh' or 'reset.refresh' if either is set. To ensure users are
advised to use the most reliable option for avoiding 'refresh_index(...)',
replace recommendation of '--quiet' with '--[no-]refresh'.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a new --[no-]refresh option that is intended to explicitly determine
whether a mixed reset should end in an index refresh.
Starting at 9ac8125d1a (reset: don't compute unstaged changes after reset
when --quiet, 2018-10-23), using the '--quiet' option results in skipping
the call to 'refresh_index(...)' at the end of a mixed reset with the goal
of improving performance. However, by coupling behavior that modifies the
index with the option that silences logs, there is no way for users to have
one without the other (i.e., silenced logs with a refreshed index) without
incurring the overhead of a separate call to 'git update-index --refresh'.
Furthermore, there is minimal user-facing documentation indicating that
--quiet skips the index refresh, potentially leading to unexpected issues
executing commands after 'git reset --quiet' that do not themselves refresh
the index (e.g., internals of 'git stash', 'git read-tree').
To mitigate these issues, '--[no-]refresh' and 'reset.refresh' are
introduced to provide a dedicated mechanism for refreshing the index. When
either is set, '--quiet' and 'reset.quiet' revert to controlling only
whether logs are silenced and do not affect index refresh.
Helped-by: Derrick Stolee <derrickstolee@github.com>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update the advice describing index refresh from "enumerate unstaged changes"
to "refresh the index." Describing 'refresh_index(...)' as "enumerating
unstaged changes" is not fully representative of what an index refresh is
doing; more generally, it updates the properties of index entries that are
affected by outside-of-index state, e.g. CE_UPTODATE, which is affected by
the file contents on-disk. This distinction is relevant to operations that
read the index but do not refresh first - e.g., 'git read-tree' - where a
stale index may cause incorrect behavior.
In addition to changing the advice message, use the "advise" function to
print advice.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
By default, git-repack(1) will update server info that is required by
the dumb HTTP transport. This can be skipped by passing the `-n` flag,
but what we're noticably missing is a config option to permanently
disable updating this information.
Add a new option "repack.updateServerInfo" which can be used to disable
the logic. Most hosting providers have turned off the dumb HTTP protocol
anyway, and on the client-side it woudln't typically be useful either.
Giving a persistent way to disable this feature thus makes quite some
sense to avoid wasting compute cycles and storage.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
By default, git-repack(1) runs `update_server_info()` to generate info
required for the dumb HTTP protocol. This can be disabled via the `-n`
flag, which then sets the `no_update_server_info` flag. Further down the
code this leads to some double-negation logic, which is about to become
more confusing as we're about to add a new config which allows the user
to permanently disable generation of the info.
Refactor the code to avoid the double-negation and add some tests which
verify that the flag continues to work as expected.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Plug random memory leaks.
* ab/plug-random-leaks:
repository.c: free the "path cache" in repo_clear()
range-diff: plug memory leak in read_patches()
range-diff: plug memory leak in common invocation
lockfile API users: simplify and don't leak "path"
commit-graph: stop fill_oids_from_packs() progress on error and free()
commit-graph: fix memory leak in misused string_list API
submodule--helper: fix trivial leak in module_add()
transport: stop needlessly copying bundle header references
bundle: call strvec_clear() on allocated strvec
remote-curl.c: free memory in cmd_main()
urlmatch.c: add and use a *_release() function
diff.c: free "buf" in diff_words_flush()
merge-base: free() allocated "struct commit **" list
index-pack: fix memory leaks
Newer version of GPGSM changed its output in a backward
incompatible way to break our code that parses its output. It also
added more processes our tests need to kill when cleaning up.
Adjustments have been made to accommodate these changes.
* fs/gpgsm-update:
t/lib-gpg: kill all gpg components, not just gpg-agent
t/lib-gpg: reload gpg components after updating trustlist
gpg-interface/gpgsm: fix for v2.3
Check the return value from parse_tree_indirect() to turn segfaults
into calls to die().
* gc/parse-tree-indirect-errors:
checkout, clone: die if tree cannot be parsed
Align the level of verbose output from the ort backend during inner
merge to that of the recursive backend.
* en/merge-ort-align-verbosity-with-recursive:
merge-ort: exclude messages from inner merges by default
Makefile refactoring with a bit of suffixes rule stripping to
optimize the runtime overhead.
* ab/make-optim-noop:
Makefiles: add and use wildcard "mkdir -p" template
Makefile: add "$(QUIET)" boilerplate to shared.mak
Makefile: move $(comma), $(empty) and $(space) to shared.mak
Makefile: move ".SUFFIXES" rule to shared.mak
Makefile: define $(LIB_H) in terms of $(FIND_SOURCE_FILES)
Makefile: disable GNU make built-in wildcard rules
Makefiles: add "shared.mak", move ".DELETE_ON_ERROR" to it
scalar Makefile: use "The default target of..." pattern
"git fetch" can make two separate fetches, but ref updates coming
from them were in two separate ref transactions under "--atomic",
which has been corrected.
* ps/fetch-atomic:
fetch: make `--atomic` flag cover pruning of refs
fetch: make `--atomic` flag cover backfilling of tags
refs: add interface to iterate over queued transactional updates
fetch: report errors when backfilling tags fails
fetch: control lifecycle of FETCH_HEAD in a single place
fetch: backfill tags before setting upstream
fetch: increase test coverage of fetches
The Git CodingGuidelines prefer the $(...) construct for command
substitution instead of using the backquotes `...`.
The backquoted form is the traditional method for command
substitution, and is supported by POSIX. However, all but the
simplest uses become complicated quickly. In particular, embedded
command substitutions and/or the use of double quotes require
careful escaping with the backslash character.
The patch was generated by:
for _f in $(find . -name "*.sh")
do
shellcheck -i SC2006 -f diff ${_f} | ifne git apply -p2
done
and then carefully proof-read.
Signed-off-by: Elia Pinto <gitter.spiros@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If a commit in a sequence of linear history has a non-monotonically
increasing commit timestamp, git name-rev might not properly name the
commit.
This occurs because name-rev uses a heuristic of the commit date to
avoid searching down tags which lead to commits that are older than the
named commit. This is intended to avoid work on larger repositories.
This heuristic impacts git name-rev, and by extension git describe
--contains which is built on top of name-rev.
Further more, if --all or --annotate-stdin is used, the heuristic is not
enabled because the full history has to be analyzed anyways. This
results in some confusion if a user sees that --annotate-stdin works but
a normal name-rev does not.
If the repository has a commit graph, we can use the generation numbers
instead of using the commit dates. This is essentially the same check
except that generation numbers make it exact, where the commit date
heuristic could be incorrect due to clock errors.
Since we're extending the notion of cutoff to more than one variable,
create a series of functions for setting and checking the cutoff. This
avoids duplication and moves access of the global cutoff and
generation_cutoff to as few functions as possible.
Add several test cases including a test that covers the new commitGraph
behavior, as well as tests for --all and --annotate-stdin with and
without commitGraphs.
Signed-off-by: Jacob Keller <jacob.keller@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix a regression in my daf1d8285e (reflog expire: don't use
lookup_commit_reference_gently(), 2021-12-22), in changing from
lookup_commit_reference_gently() to lookup_commit() we stopped trying
to call deref_tag() and parse_object() on the provided OID, but we
also started returning non-NULL for the null_oid().
As a result we'd emit an error() via mark_reachable() later in this
function as we tried to invoke parse_commit() on it.
Reported-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Tested-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The xfuncname pattern finds func/class declarations
in diffs to display as a hunk header. The word_regex
pattern finds individual tokens in Kotlin code to generate
appropriate diffs.
This patch adds xfuncname regex and word_regex for Kotlin
language.
Signed-off-by: Jaydeep P Das <jaydeepjd.8914@gmail.com>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Pipes ignore error codes of LHS command and thus we should not use
them with Git in tests. As an alternative, use a 'tmp' file to write
the Git output so we can test the exit code.
Signed-off-by: Shubham Mishra <shivam828787@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Pipes ignore error codes of LHS command and thus we should not use
them with Git in tests. As an alternative, use a 'tmp' file to write
the Git output so we can test the exit code.
Signed-off-by: Shubham Mishra <shivam828787@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit introduces the new ability for the user to harden
the index. In the event of a system crash, the index must be
durable for the user to actually find a file that has been added
to the repo and then deleted from the working tree.
We use the presence of the COMMIT_LOCK flag and absence of the
alternate_index_output as a proxy for determining whether we're
updating the persistent index of the repo or some temporary
index. We don't sync these temporary indexes.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This change introduces code to parse the core.fsync setting and
configure the fsync_components variable.
core.fsync is configured as a comma-separated list of component names to
sync. Each time a core.fsync variable is encountered in the
configuration heirarchy, we start off with a clean state with the
platform default value. Passing 'none' resets the value to indicate
nothing will be synced. We gather all negative and positive entries from
the comma separated list and then compute the new value by removing all
the negative entries and adding all of the positive entries.
We issue a warning for components that are not recognized so that the
configuration code is compatible with configs from future versions of
Git with more repo components.
Complete documentation for the new setting is included in a later patch
in the series so that it can be reviewed once in final form.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit introduces the infrastructure for the core.fsync
configuration knob. The repository components we want to sync
are identified by flags so that we can turn on or off syncing
for specific components.
If core.fsyncObjectFiles is set and the core.fsync configuration
also includes FSYNC_COMPONENT_LOOSE_OBJECT, we will fsync any
loose objects. This picks the strictest data integrity behavior
if core.fsync and core.fsyncObjectFiles are set to conflicting values.
This change introduces the currently unused fsync_component
helper, which will be used by a later patch that adds fsyncing to
the refs backend.
Actual configuration and documentation of the fsync components
list are in other patches in the series to separate review of
the underlying mechanism from the policy of how it's configured.
Helped-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit introduces the `core.fsyncMethod` configuration
knob, which can currently be set to `fsync` or `writeout-only`.
The new writeout-only mode attempts to tell the operating system to
flush its in-memory page cache to the storage hardware without issuing a
CACHE_FLUSH command to the storage controller.
Writeout-only fsync is significantly faster than a vanilla fsync on
common hardware, since data is written to a disk-side cache rather than
all the way to a durable medium. Later changes in this patch series will
take advantage of this primitive to implement batching of hardware
flushes.
When git_fsync is called with FSYNC_WRITEOUT_ONLY, it may fail and the
caller is expected to do an ordinary fsync as needed.
On Apple platforms, the fsync system call does not issue a CACHE_FLUSH
directive to the storage controller. This change updates fsync to do
fcntl(F_FULLFSYNC) to make fsync actually durable. We maintain parity
with existing behavior on Apple platforms by setting the default value
of the new core.fsyncMethod option.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Including NTSecAPI.h in git-compat-util.h causes build errors in any
other file that includes winternl.h. NTSecAPI.h was included in order to
get access to the RtlGenRandom cryptographically secure PRNG. This
change scopes the inclusion of ntsecapi.h to wrapper.c, which is the only
place that it's actually needed.
The build breakage is due to the definition of UNICODE_STRING in
NtSecApi.h:
#ifndef _NTDEF_
typedef LSA_UNICODE_STRING UNICODE_STRING, *PUNICODE_STRING;
typedef LSA_STRING STRING, *PSTRING ;
#endif
LsaLookup.h:
typedef struct _LSA_UNICODE_STRING {
USHORT Length;
USHORT MaximumLength;
#ifdef MIDL_PASS
[size_is(MaximumLength/2), length_is(Length/2)]
#endif // MIDL_PASS
PWSTR Buffer;
} LSA_UNICODE_STRING, *PLSA_UNICODE_STRING;
winternl.h also defines UNICODE_STRING:
typedef struct _UNICODE_STRING {
USHORT Length;
USHORT MaximumLength;
PWSTR Buffer;
} UNICODE_STRING;
typedef UNICODE_STRING *PUNICODE_STRING;
Both definitions have equivalent layouts. Apparently these internal
Windows headers aren't designed to be included together. This is
an oversight in the headers and does not represent an incompatibility
between the APIs.
Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the block SHA-1 code, we have special assembly code for i386 and
amd64 to perform rotations with assembly. This is supposed to help pick
the correct rotation operation depending on which rotation is smaller,
which can help some systems perform slightly better, since any circular
rotation can be specified as either a rotate left or a rotate right.
However, this isn't needed, so we should remove it.
First, SHA-1, like SHA-2, uses fixed constant rotates. Thus, all
rotation amounts are known at compile time and are in fact baked into
the code. Fortunately, peephole optimizers recognize rotations
specified in the normal way and automatically emit the correct code,
including a preference for choosing a rotate left versus a rotate right.
This has been the case for well over a decade, and is a standard example
of the utility of a peephole optimizer.
Moreover, all modern CPUs, with the exception of extremely limited
embedded CPUs such as some Cortex-M processors, provide a barrel
shifter, which lets the CPU perform rotates of any bit amount in
constant time. This is valuable for many cryptographic algorithms to
improve performance, and is required to prevent timing attacks in
algorithms which use data-dependent rotations (which don't include the
hash algorithms we use). As a result, even though the compiler does the
correct optimization, it isn't even needed here and either a left or a
right rotate is equally acceptable.
In fact, the SHA-256 code already takes this into account and just
writes the simple code using an inline function to let the compiler
optimize it for us.
The downside of using this code, however, is that it uses a GCC
extension, which makes the compiler complain when using -pedantic unless
it's prefixed with __extension__. We could fix that, but since it's
not needed, let's just remove it. We haven't noticed this because
almost everyone uses the SHA1DC code instead, but it still shows up for
some people.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* pw/single-key-interactive:
add -p: disable stdin buffering when interactive.singlekey is set
terminal: set VMIN and VTIME in non-canonical mode
terminal: pop signal handler when terminal is restored
terminal: always reset terminal when reading without echo
131b94a10a ("test-lib.sh: Use GLIBC_TUNABLES instead of MALLOC_CHECK_ on
glibc >= 2.34", 2022-03-04) introduced "local" variables without
declaring them as such. This conflicts with their use in some tests (at
least when running them with dash), leading to test failures in:
t0006-date.sh
t2002-checkout-cache-u.sh
t3430-rebase-merges.sh
t4138-apply-ws-expansion.sh
t4124-apply-ws-rule.sh
Declare those variables as local to let the tests pass again.
Signed-off-by: Michael J Gruber <git@grubix.eu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
