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>
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 `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>
In sparse-checkouts, files mis-marked as missing from the working tree
could lead to later problems. Such files were hard to discover, and
harder to correct. Automatically detecting and correcting the marking
of such files has been added to avoid these problems.
* en/present-despite-skipped:
repo_read_index: add config to expect files outside sparse patterns
Accelerate clear_skip_worktree_from_present_files() by caching
Update documentation related to sparsity and the skip-worktree bit
repo_read_index: clear SKIP_WORKTREE bit from files present in worktree
unpack-trees: fix accidental loss of user changes
t1011: add testcase demonstrating accidental loss of user modifications
Typically with sparse checkouts, we expect files outside the sparsity
patterns to be marked as SKIP_WORKTREE and be missing from the working
tree. Sometimes this expectation would be violated however; including
in cases such as:
* users grabbing files from elsewhere and writing them to the worktree
(perhaps by editing a cached copy in an editor, copying/renaming, or
even untarring)
* various git commands having incomplete or no support for the
SKIP_WORKTREE bit[1,2]
* users attempting to "abort" a sparse-checkout operation with a
not-so-early Ctrl+C (updating $GIT_DIR/info/sparse-checkout and the
working tree is not atomic)[3].
When the SKIP_WORKTREE bit in the index did not reflect the presence of
the file in the working tree, it traditionally caused confusion and was
difficult to detect and recover from. So, in a sparse checkout, since
af6a51875a (repo_read_index: clear SKIP_WORKTREE bit from files present
in worktree, 2022-01-14), Git automatically clears the SKIP_WORKTREE
bit at index read time for entries corresponding to files that are
present in the working tree.
There is another workflow, however, where it is expected that paths
outside the sparsity patterns appear to exist in the working tree and
that they do not lose the SKIP_WORKTREE bit, at least until they get
modified. A Git-aware virtual file system[4] takes advantage of its
position as a file system driver to expose all files in the working
tree, fetch them on demand using partial clone on access, and tell Git
to pay attention to them on demand by updating the sparse checkout
pattern on writes. This means that commands like "git status" only have
to examine files that have potentially been modified, whereas commands
like "ls" are able to show the entire codebase without requiring manual
updates to the sparse checkout pattern.
Thus since af6a51875a, Git with such Git-aware virtual file systems
unsets the SKIP_WORKTREE bit for all files and commands like "git
status" have to fetch and examine them all.
Introduce a configuration setting sparse.expectFilesOutsideOfPatterns to
allow limiting the tracked set of files to a small set once again. A
Git-aware virtual file system or other application that wants to
maintain files outside of the sparse checkout can set this in a
repository to instruct Git not to check for the presence of
SKIP_WORKTREE files. The setting defaults to false, so most users of
sparse checkout will still get the benefit of an automatically updating
index to recover from the variety of difficult issues detailed in
af6a51875a for paths with SKIP_WORKTREE set despite the path being
present.
[1] https://lore.kernel.org/git/xmqqbmb1a7ga.fsf@gitster-ct.c.googlers.com/
[2] The three long paragraphs in the middle of
https://lore.kernel.org/git/CABPp-BH9tju7WVm=QZDOvaMDdZbpNXrVWQdN-jmfN8wC6YVhmw@mail.gmail.com/
[3] https://lore.kernel.org/git/CABPp-BFnFpzwGC11TLoLs8YK5yiisA5D5-fFjXnJsbESVDwZsA@mail.gmail.com/
[4] such as the vfsd described in
https://lore.kernel.org/git/20220207190320.2960362-1-jonathantanmy@google.com/
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Plug (some) memory leaks around parse_date_format().
* ab/date-mode-release:
date API: add and use a date_mode_release()
date API: add basic API docs
date API: provide and use a DATE_MODE_INIT
date API: create a date.h, split from cache.h
cache.h: remove always unused show_date_human() declaration
"git sparse-checkout" wants to work with per-worktree configuration,
but did not work well in a worktree attached to a bare repository.
* ds/sparse-checkout-requires-per-worktree-config:
config: make git_configset_get_string_tmp() private
worktree: copy sparse-checkout patterns and config on add
sparse-checkout: set worktree-config correctly
config: add repo_config_set_worktree_gently()
worktree: create init_worktree_config()
Documentation: add extensions.worktreeConfig details
Move the declaration of the date.c functions from cache.h, and adjust
the relevant users to include the new date.h header.
The show_ident_date() function belonged in pretty.h (it's defined in
pretty.c), its two users outside of pretty.c didn't strictly need to
include pretty.h, as they get it indirectly, but let's add it to them
anyway.
Similarly, the change to "builtin/{fast-import,show-branch,tag}.c"
isn't needed as far as the compiler is concerned, but since they all
use the "DATE_MODE()" macro we now define in date.h, let's have them
include it.
We could simply include this new header in "cache.h", but as this
change shows these functions weren't common enough to warrant
including in it in the first place. By moving them out of cache.h
changes to this API will no longer cause a (mostly) full re-build of
the project when "make" is run.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The conditional inclusion mechanism of configuration files using
"[includeIf <condition>]" learns to base its decision on the
URL of the remote repository the repository interacts with.
* jt/conditional-config-on-remote-url:
config: include file if remote URL matches a glob
config: make git_config_include() static
This method was created in f1de981e8 (config: fix leaks from
git_config_get_string_const(), 2020-08-14) but its only use was in the
repo_config_get_string_tmp() method, also declared in config.h and
implemented in config.c. Since this is otherwise unused and is a very
similar implementation to git_configset_get_value(), let's remove this
declaration.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some config settings, such as those for sparse-checkout, are likely
intended to only apply to one worktree at a time. To make this write
easier, add a new config API method, repo_config_set_worktree_gently().
This method will attempt to write to the worktree-specific config, but
will instead write to the common config file if worktree config is not
enabled. The next change will introduce a consumer of this method.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is a feature that supports config file inclusion conditional on
whether the repo has a remote with a URL that matches a glob.
Similar to my previous work on remote-suggested hooks [1], the main
motivation is to allow remote repo administrators to provide recommended
configs in a way that can be consumed more easily (e.g. through a
package installable by a package manager - it could, for example,
contain a file to be included conditionally and a post-install script
that adds the include directive to the system-wide config file).
In order to do this, Git reruns the config parsing mechanism upon
noticing the first URL-conditional include in order to find all remote
URLs, and these remote URLs are then used to determine if that first and
all subsequent includes are executed. Remote URLs are not allowed to be
configued in any URL-conditionally-included file.
[1] https://lore.kernel.org/git/cover.1623881977.git.jonathantanmy@google.com/
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Acked-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is not used from outside the file in which it is declared.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Acked-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git -c branch.autosetupmerge=inherit branch new old" makes "new"
to have the same upstream as the "old" branch, instead of marking
"old" itself as its upstream.
* js/branch-track-inherit:
config: require lowercase for branch.*.autosetupmerge
branch: add flags and config to inherit tracking
branch: accept multiple upstream branches for tracking
Although we only documented that branch.*.autosetupmerge would accept
"always" as a value, the actual implementation would accept any
combination of upper- or lower-case. Fix this to be consistent with
documentation and with other values of this config variable.
Signed-off-by: Josh Steadmon <steadmon@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It can be helpful when creating a new branch to use the existing
tracking configuration from the branch point. However, there is
currently not a method to automatically do so.
Teach git-{branch,checkout,switch} an "inherit" argument to the
"--track" option. When this is set, creating a new branch will cause the
tracking configuration to default to the configuration of the branch
point, if set.
For example, if branch "main" tracks "origin/main", and we run
`git checkout --track=inherit -b feature main`, then branch "feature"
will track "origin/main". Thus, `git status` will show us how far
ahead/behind we are from origin, and `git pull` will pull from origin.
This is particularly useful when creating branches across many
submodules, such as with `git submodule foreach ...` (or if running with
a patch such as [1], which we use at $job), as it avoids having to
manually set tracking info for each submodule.
Since we've added an argument to "--track", also add "--track=direct" as
another way to explicitly get the original "--track" behavior ("--track"
without an argument still works as well).
Finally, teach branch.autoSetupMerge a new "inherit" option. When this
is set, "--track=inherit" becomes the default behavior.
[1]: https://lore.kernel.org/git/20180927221603.148025-1-sbeller@google.com/
Signed-off-by: Josh Steadmon <steadmon@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the git_die_config() function added in 5a80e97c82 (config: add
`git_die_config()` to the config-set API, 2014-08-07) to use the
public callbacks in the usage.[ch] API instead of the the underlying
vreportf() function.
In preceding commits the rest of the vreportf() users outside of
usage.c was migrated to die_message(), so we can now make it "static".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix a memory leak in the error() path in handle_path_include(), this
allows us to run t1305-config-include.sh under SANITIZE=leak,
previously 4 tests there would fail. This fixes up a leak in
9b25a0b52e (config: add include directive, 2012-02-06).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The git_config_key_is_valid() function got left behind in a
refactoring in a9bcf6586d (alias: use the early config machinery to
expand aliases, 2017-06-14),
It previously had two users when it was added in 9e9de18f1a (config:
silence warnings for command names with invalid keys, 2015-08-24), and
after 6a1e1bc0a1 (pager: use callbacks instead of configset,
2016-09-12) only one remained.
By removing it we can get rid of the "quiet" branches in this
function, as well as cases where "store_key" is NULL, for which there
are no other users.
Out of the 5 callers of git_config_parse_key() only one needs to pass
a non-NULL "size_t *baselen_", so we could remove the third parameter
from the public interface. I did not find that potential
simplification to be worthwhile.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The code to make "git grep" recurse into submodules has been
updated to migrate away from the "add submodule's object store as
an alternate object store" mechanism (which is suboptimal).
* jt/grep-wo-submodule-odb-as-alternate:
t7814: show lack of alternate ODB-adding
submodule-config: pass repo upon blob config read
grep: add repository to OID grep sources
grep: allocate subrepos on heap
grep: read submodule entry with explicit repo
grep: typesafe versions of grep_source_init
grep: use submodule-ODB-as-alternate lazy-addition
submodule: lazily add submodule ODBs as alternates
Since 8de7eeb54b (compression: unify pack.compression configuration
parsing, 2016-11-15) the variables core_compression_level and
core_compression_seen are only set, but never read. Remove them.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When reading the config of a submodule, if reading from a blob, read
using an explicitly specified repository instead of by adding the
submodule's ODB as an alternate and then reading an object from
the_repository.
This makes the "grep --recurse-submodules with submodules without
.gitmodules in the working tree" test in t7814 work when
GIT_TEST_FATAL_REGISTER_SUBMODULE_ODB is true.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Reviewed-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Pathname expansion (like "~username/") learned a way to specify a
location relative to Git installation (e.g. its $sharedir which is
$(prefix)/share), with "%(prefix)".
* js/expand-runtime-prefix:
expand_user_path: allow in-flight topics to keep using the old name
interpolate_path(): allow specifying paths relative to the runtime prefix
Use a better name for the function interpolating paths
expand_user_path(): clarify the role of the `real_home` parameter
expand_user_path(): remove stale part of the comment
tests: exercise the RUNTIME_PREFIX feature
It is not immediately clear what `expand_user_path()` means, so let's
rename it to `interpolate_path()`. This also opens the path for
interpolating more than just a home directory.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update the documentation not to assume users are of certain gender
and adds to guidelines to do so.
* ds/gender-neutral-doc:
*: fix typos
comments: avoid using the gender of our users
doc: avoid using the gender of other people
Code cleanup around struct_type_init() functions.
* ab/struct-init:
string-list.h users: change to use *_{nodup,dup}()
string-list.[ch]: add a string_list_init_{nodup,dup}()
dir.[ch]: replace dir_init() with DIR_INIT
*.c *_init(): define in terms of corresponding *_INIT macro
*.h: move some *_INIT to designated initializers
Change all in-tree users of the string_list_init(LIST, BOOL) API to
use string_list_init_{nodup,dup}(LIST) instead.
As noted in the preceding commit let's leave the now-unused
string_list_init() wrapper in-place for any in-flight users, it can be
removed at some later date.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Linux users may benefit from additional information on how to
avoid ENOMEM from mmap despite the system having enough RAM to
accomodate them. We can't reliably unmap pack windows to work
around the issue since malloc and other library routines may
mmap without our knowledge.
Signed-off-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git for Windows is compiled with a runtime prefix, and that runtime
prefix is typically `C:/Program Files/Git/mingw64`. As we want the
system gitconfig to live in the sibling directory `etc`, we define the
relative path as `../etc/gitconfig`.
However, as reported by Philip Oakley, the output of `git config
--show-origin --system -l` looks rather ugly, as it shows the path as
`file:C:/Program Files/Git/mingw64/../etc/gitconfig`, i.e. with the
`mingw64/../` part.
By normalizing the path, we get a prettier path.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These typos were found while searching the codebase for gendered
pronouns. In the case of t9300-fast-import.sh, remove a confusing
comment that is unnecessary to the understanding of the test.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Replace GIT_CONFIG_NOSYSTEM mechanism to decline from reading the
system-wide configuration file with GIT_CONFIG_SYSTEM that lets
users specify from which file to read the system-wide configuration
(setting it to an empty file would essentially be the same as
setting NOSYSTEM), and introduce GIT_CONFIG_GLOBAL to override the
per-user configuration in $HOME/.gitconfig.
* ps/config-global-override:
t1300: fix unset of GIT_CONFIG_NOSYSTEM leaking into subsequent tests
config: allow overriding of global and system configuration
config: unify code paths to get global config paths
config: rename `git_etc_config()`
In order to have git run in a fully controlled environment without any
misconfiguration, it may be desirable for users or scripts to override
global- and system-level configuration files. We already have a way of
doing this, which is to unset both HOME and XDG_CONFIG_HOME environment
variables and to set `GIT_CONFIG_NOGLOBAL=true`. This is quite kludgy,
and unsetting the first two variables likely has an impact on other
executables spawned by such a script.
The obvious way to fix this would be to introduce `GIT_CONFIG_NOGLOBAL`
as an equivalent to `GIT_CONFIG_NOSYSTEM`. But in the past, it has
turned out that this design is inflexible: we cannot test system-level
parsing of the git configuration in our test harness because there is no
way to change its location, so all tests run with `GIT_CONFIG_NOSYSTEM`
set.
Instead of doing the same mistake with `GIT_CONFIG_NOGLOBAL`, introduce
two new variables `GIT_CONFIG_GLOBAL` and `GIT_CONFIG_SYSTEM`:
- If unset, git continues to use the usual locations.
- If set to a specific path, we skip reading the normal
configuration files and instead take the path. By setting the path
to `/dev/null`, no configuration will be loaded for the respective
level.
This implements the usecase where we want to execute code in a sanitized
environment without any potential misconfigurations via `/dev/null`, but
is more flexible and allows for more usecases than simply adding
`GIT_CONFIG_NOGLOBAL`.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There's two callsites which assemble global config paths, once in the
config loading code and once in the git-config(1) builtin. We're about
to implement a way to override global config paths via an environment
variable which would require us to adjust both sites.
Unify both code paths into a single `git_global_config()` function which
returns both paths for `~/.gitconfig` and the XDG config file. This will
make the subsequent patch which introduces the new envvar easier to
implement.
No functional changes are expected from this patch.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `git_etc_gitconfig()` function retrieves the system-level path of
the configuration file. We're about to introduce a way to override it
via an environment variable, at which point the name of this function
would start to become misleading.
Rename the function to `git_system_config()` as a preparatory step.
While at it, the function is also refactored to pass memory ownership to
the caller. This is done to better match semantics of
`git_global_config()`, which is going to be introduced in the next
commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remove a use of GIT_TEST_GETTEXT_POISON added in f276e2a469 (config:
improve error message for boolean config, 2021-02-11).
This was simultaneously in-flight with my d162b25f95 (tests: remove
support for GIT_TEST_GETTEXT_POISON, 2021-01-20) which removed the
rest of the GIT_TEST_GETTEXT_POISON code.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add and apply a semantic patch for converting code that open-codes
CALLOC_ARRAY to use it instead. It shortens the code and infers the
element size automatically.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The error message given when a configuration variable that is
expected to have a boolean value has been improved.
* ak/config-bad-bool-error:
config: improve error message for boolean config
Currently invalid boolean config values return messages about 'bad
numeric', which is slightly misleading when the error was due to a
boolean value. We can improve the developer experience by returning a
boolean error message when we know the value is neither a bool text or
int.
before with an invalid boolean value of `non-boolean`, its unclear what
numeric is referring to:
fatal: bad numeric config value 'non-boolean' for 'commit.gpgsign': invalid unit
now the error message mentions `non-boolean` is a bad boolean value:
fatal: bad boolean config value 'non-boolean' for 'commit.gpgsign'
Signed-off-by: Andrew Klotz <agc.klotz@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Get rid of "GETTEXT_POISON" support altogether, which may or may
not be controversial.
* ab/detox-gettext-tests:
tests: remove uses of GIT_TEST_GETTEXT_POISON=false
tests: remove support for GIT_TEST_GETTEXT_POISON
ci: remove GETTEXT_POISON jobs
Introduce two new ways to feed configuration variable-value pairs
via environment variables, and tweak the way GIT_CONFIG_PARAMETERS
encodes variable/value pairs to make it more robust.
* ps/config-env-pairs:
config: allow specifying config entries via envvar pairs
environment: make `getenv_safe()` a public function
config: store "git -c" variables using more robust format
config: parse more robust format in GIT_CONFIG_PARAMETERS
config: extract function to parse config pairs
quote: make sq_dequote_step() a public function
config: add new way to pass config via `--config-env`
git: add `--super-prefix` to usage string
This removes the ability to inject "poison" gettext() messages via the
GIT_TEST_GETTEXT_POISON special test setup.
I initially added this as a compile-time option in bb946bba76 (i18n:
add GETTEXT_POISON to simulate unfriendly translator, 2011-02-22), and
most recently modified to be toggleable at runtime in
6cdccfce1e (i18n: make GETTEXT_POISON a runtime option, 2018-11-08)..
The reason for its removal is that the trade-off of maintaining it
v.s. what it's getting us has long since flipped. When gettext was
integrated in 5e9637c629 (i18n: add infrastructure for translating
Git with gettext, 2011-11-18) there was understandable concern on the
Git ML that in marking messages for translation en-masse we'd
inadvertently mark plumbing messages. The GETTEXT_POISON facility was
a way to smoke those out via our test suite.
Nowadays however we're done (or almost entirely done) with any marking
of messages for translation. New messages are usually marked by their
authors, who'll know whether it makes sense to translate them or
not. If not any errors in marking the messages are much more likely to
be spotted in review than in the the initial deluge of i18n patches in
the 2011-2012 era.
So let's just remove this. This leaves the test suite in a state where
we still have a lot of test_i18n, C_LOCALE_OUTPUT
etc. uses. Subsequent commits will remove those too.
The change to t/lib-rebase.sh is a selective revert of the relevant
part of f2d17068fd (i18n: rebase-interactive: mark comments of squash
for translation, 2016-06-17), and the comment in
t/t3406-rebase-message.sh is from c7108bf9ed (i18n: rebase: mark
messages for translation, 2012-07-25).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The configuration variable 'core.abbrev' can be set to 'no' to
force no abbreviation regardless of the hash algorithm.
* ew/decline-core-abbrev:
core.abbrev=no disables abbreviations
While we currently have the `GIT_CONFIG_PARAMETERS` environment variable
which can be used to pass runtime configuration data to git processes,
it's an internal implementation detail and not supposed to be used by
end users.
Next to being for internal use only, this way of passing config entries
has a major downside: the config keys need to be parsed as they contain
both key and value in a single variable. As such, it is left to the user
to escape any potentially harmful characters in the value, which is
quite hard to do if values are controlled by a third party.
This commit thus adds a new way of adding config entries via the
environment which gets rid of this shortcoming. If the user passes the
`GIT_CONFIG_COUNT=$n` environment variable, Git will parse environment
variable pairs `GIT_CONFIG_KEY_$i` and `GIT_CONFIG_VALUE_$i` for each
`i` in `[0,n)`.
While the same can be achieved with `git -c <name>=<value>`, one may
wish to not do so for potentially sensitive information. E.g. if one
wants to set `http.extraHeader` to contain an authentication token,
doing so via `-c` would trivially leak those credentials via e.g. ps(1),
which typically also shows command arguments.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The previous commit added a new format for $GIT_CONFIG_PARAMETERS which
is able to robustly handle subsections with "=" in them. Let's start
writing the new format. Unfortunately, this does much less than you'd
hope, because "git -c" itself has the same ambiguity problem! But it's
still worth doing:
- we've now pushed the problem from the inter-process communication
into the "-c" command-line parser. This would free us up to later
add an unambiguous format there (e.g., separate arguments like "git
--config key value", etc).
- for --config-env, the parser already disallows "=" in the
environment variable name. So:
git --config-env section.with=equals.key=ENVVAR
will robustly set section.with=equals.key to the contents of
$ENVVAR.
The new test shows the improvement for --config-env.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we stuff config options into GIT_CONFIG_PARAMETERS, we shell-quote
each one as a single unit, like:
'section.one=value1' 'section.two=value2'
On the reading side, we de-quote to get the individual strings, and then
parse them by splitting on the first "=" we find. This format is
ambiguous, because an "=" may appear in a subsection. So the config
represented in a file by both:
[section "subsection=with=equals"]
key = value
and:
[section]
subsection = with=equals.key=value
ends up in this flattened format like:
'section.subsection=with=equals.key=value'
and we can't tell which was desired. We have traditionally resolved this
by taking the first "=" we see starting from the left, meaning that we
allowed arbitrary content in the value, but not in the subsection.
Let's make our environment format a bit more robust by separately
quoting the key and value. That turns those examples into:
'section.subsection=with=equals.key'='value'
and:
'section.subsection'='with=equals.key=value'
respectively, and we can tell the difference between them. We can detect
which format is in use for any given element of the list based on the
presence of the unquoted "=". That means we can continue to allow the
old format to work to support any callers which manually used the old
format, and we can even intermingle the two formats. The old format
wasn't documented, and nobody was supposed to be using it. But it's
likely that such callers exist in the wild, so it's nice if we can avoid
breaking them. Likewise, it may be possible to trigger an older version
of "git -c" that runs a script that calls into a newer version of "git
-c"; that new version would see the intermingled format.
This does create one complication, which is that the obvious format in
the new scheme for
[section]
some-bool
is:
'section.some-bool'
with no equals. We'd mistake that for an old-style variable. And it even
has the same meaning in the old style, but:
[section "with=equals"]
some-bool
does not. It would be:
'section.with=equals=some-bool'
which we'd take to mean:
[section]
with = equals=some-bool
in the old, ambiguous style. Likewise, we can't use:
'section.some-bool'=''
because that's ambiguous with an actual empty string. Instead, we'll
again use the shell-quoting to give us a hint, and use:
'section.some-bool'=
to show that we have no value.
Note that this commit just expands the reading side. We'll start writing
the new format via "git -c" in a future patch. In the meantime, the
existing "git -c" tests will make sure we didn't break reading the old
format. But we'll also add some explicit coverage of the two formats to
make sure we continue to handle the old one after we move the writing
side over.
And one final note: since we're now using the shell-quoting as a
semantically meaningful hint, this closes the door to us ever allowing
arbitrary shell quoting, like:
'a'shell'would'be'ok'with'this'.key=value
But we have never supported that (only what sq_quote() would produce),
and we are probably better off keeping things simple, robust, and
backwards-compatible, than trying to make it easier for humans. We'll
continue not to advertise the format of the variable to users, and
instead keep "git -c" as the recommended mechanism for setting config
(even if we are trying to be kind not to break users who may be relying
on the current undocumented format).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
