"format-patch" has learned a new option to zero-out the commit
object name on the mbox "From " line.
* bc/format-patch-null-from-line:
format-patch: check that header line has expected format
format-patch: add an option to suppress commit hash
sha1_file.c: introduce a null_oid constant
null_oid is the struct object_id equivalent to null_sha1.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
More transition from "unsigned char[40]" to "struct object_id".
This needed a few merge fixups, but is mostly disentangled from other
topics.
* bc/object-id:
remote: convert functions to struct object_id
Remove get_object_hash.
Convert struct object to object_id
Add several uses of get_object_hash.
object: introduce get_object_hash macro.
ref_newer: convert to use struct object_id
push_refs_with_export: convert to struct object_id
get_remote_heads: convert to struct object_id
parse_fetch: convert to use struct object_id
add_sought_entry_mem: convert to struct object_id
Convert struct ref to use object_id.
sha1_file: introduce has_object_file helper.
Code preparation for pluggable ref backends.
* dt/refs-backend-pre-vtable:
refs: break out ref conflict checks
files_log_ref_write: new function
initdb: make safe_create_dir public
refs: split filesystem-based refs code into a new file
refs/refs-internal.h: new header file
refname_is_safe(): improve docstring
pack_if_possible_fn(): use ref_type() instead of is_per_worktree_ref()
copy_msg(): rename to copy_reflog_msg()
verify_refname_available(): new function
verify_refname_available(): rename function
Apple's common crypto implementation of SHA1_Update() does not take
more than 4GB at a time, and we now have a compile-time workaround
for it.
* ad/sha1-update-chunked:
sha1: allow limiting the size of the data passed to SHA1_Update()
sha1: provide another level of indirection for the SHA-1 functions
Add has_object_file, which is a wrapper around has_sha1_file, but for
struct object_id.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Jeff King <peff@peff.net>
Having a leftover .idx file without corresponding .pack file in
the repository hurts performance; "git gc" learned to prune them.
* dk/gc-idx-wo-pack:
gc: remove garbage .idx files from pack dir
t5304: test cleaning pack garbage
prepare_packed_git(): refactor garbage reporting in pack directory
Soon we will want to create initdb functions for ref backends, and
code from initdb that calls this function needs to move into the files
backend. So this function needs to be public.
Signed-off-by: David Turner <dturner@twopensource.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Jeff King <peff@peff.net>
Using the previous commit's inredirection mechanism for SHA1,
support a chunked implementation of SHA1_Update() that limits the
amount of data in the chunk passed to SHA1_Update().
This is enabled by using the Makefile variable SHA1_MAX_BLOCK_SIZE
to specify chunk size. When using Apple's CommonCrypto library this
is set to 1GiB (the implementation cannot handle more 4GiB).
Signed-off-by: Atousa Pahlevan Duprat <apahlevan@ieee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The git source uses git_SHA1_Update() and friends to call into the
code that computes the hashes. Traditionally, we used to map these
directly to underlying implementation of the SHA-1 hash (e.g.
SHA1_Update() from OpenSSL or blk_SHA1_Update() from block-sha1/).
This arrangement however makes it hard to tweak behaviour of the
underlying implementation without fully replacing. If we want to
introduce a tweaked_SHA1_Update() wrapper to implement the "Update"
in a slightly different way, for example, the implementation of the
wrapper still would want to call into the underlying implementation,
but tweaked_SHA1_Update() cannot call git_SHA1_Update() to get to
the underlying implementation (often but not always SHA1_Update()).
Add another level of indirection that maps platform_SHA1_Update()
and friends to their underlying implementations, and by default make
git_SHA1_Update() and friends map to platform_SHA1_* functions.
Doing it this way will later allow us to map git_SHA1_Update() to
tweaked_SHA1_Update(), and the latter can use platform_SHA1_Update()
in its implementation.
Signed-off-by: Atousa Pahlevan Duprat <apahlevan@ieee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The name-hash subsystem that is used to cope with case insensitive
filesystems keeps track of directories and their on-filesystem
cases for all the paths in the index by holding a pointer to a
randomly chosen cache entry that is inside the directory (for its
ce->ce_name component). This pointer was not updated even when the
cache entry was removed from the index, leading to use after free.
This was fixed by recording the path for each directory instead of
borrowing cache entries and restructuring the API somewhat.
* dt/name-hash-dir-entry-fix:
name-hash: don't reuse cache_entry in dir_entry
Prepare for Git on-disk repository representation to undergo
backward incompatible changes by introducing a new repository
format version "1", with an extension mechanism.
* jk/repository-extension:
introduce "preciousObjects" repository extension
introduce "extensions" form of core.repositoryformatversion
Stop reusing cache_entry in dir_entry; doing so causes a
use-after-free bug.
During merges, we free entries that we no longer need in the
destination index. But those entries might have also been stored in
the dir_entry cache, and when a later call to add_to_index found them,
they would be used after being freed.
To prevent this, change dir_entry to store a copy of the name instead
of a pointer to a cache_entry. This entails some refactoring of code
that expects the cache_entry.
Keith McGuigan <kmcguigan@twitter.com> diagnosed this bug and wrote
the initial patch, but this version does not use any of Keith's code.
Helped-by: Keith McGuigan <kmcguigan@twitter.com>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: David Turner <dturner@twopensource.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many allocations that is manually counted (correctly) that are
followed by strcpy/sprintf have been replaced with a less error
prone constructs such as xstrfmt.
Macintosh-specific breakage was noticed and corrected in this
reroll.
* jk/war-on-sprintf: (70 commits)
name-rev: use strip_suffix to avoid magic numbers
use strbuf_complete to conditionally append slash
fsck: use for_each_loose_file_in_objdir
Makefile: drop D_INO_IN_DIRENT build knob
fsck: drop inode-sorting code
convert strncpy to memcpy
notes: document length of fanout path with a constant
color: add color_set helper for copying raw colors
prefer memcpy to strcpy
help: clean up kfmclient munging
receive-pack: simplify keep_arg computation
avoid sprintf and strcpy with flex arrays
use alloc_ref rather than hand-allocating "struct ref"
color: add overflow checks for parsing colors
drop strcpy in favor of raw sha1_to_hex
use sha1_to_hex_r() instead of strcpy
daemon: use cld->env_array when re-spawning
stat_tracking_info: convert to argv_array
http-push: use an argv_array for setup_revisions
fetch-pack: use argv_array for index-pack / unpack-objects
...
"git clone --dissociate" runs a big "git repack" process at the
end, and it helps to close file descriptors that are open on the
packs and their idx files before doing so on filesystems that
cannot remove a file that is still open.
* js/clone-dissociate:
clone --dissociate: avoid locking pack files
sha1_file.c: add a function to release all packs
sha1_file: consolidate code to close a pack's file descriptor
t5700: demonstrate a Windows file locking issue with `git clone --dissociate`
The submodule code has been taught to work better with separate
work trees created via "git worktree add".
* mk/submodule-gitdir-path:
path: implement common_dir handling in git_pathdup_submodule()
submodule refactor: use strbuf_git_path_submodule() in add_submodule_odb()
On Windows, files that are in use cannot be removed or renamed. That
means that we have to release pack files when we are about to, say,
repack them. Let's introduce a convenient function to close all the
pack files and their idx files.
While at it, we consolidate the close windows/close fd/close index
stanza in `free_pack_by_name()` into the `close_pack()` function that
is used by the new `close_all_packs()` function to avoid repeated code.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git log --date=local" used to only show the normal (default)
format in the local timezone. The command learned to take 'local'
as an instruction to use the local timezone with other formats,
e.g. "git show --date=rfc-local".
* jk/date-local:
t6300: add tests for "-local" date formats
t6300: make UTC and local dates different
date: make "local" orthogonal to date format
date: check for "local" before anything else
t6300: add test for "raw" date format
t6300: introduce test_date() helper
fast-import: switch crash-report date to iso8601
Documentation/rev-list: don't list date formats
Documentation/git-for-each-ref: don't list date formats
Documentation/config: don't list date formats
Documentation/blame-options: don't list date formats
We have the path "foo.idx", and we create a buffer big
enough to hold "foo.pack" and "foo.keep", and then strcpy
straight into it. This isn't a bug (we have enough space),
but it's very hard to tell from the strcpy that this is so.
Let's instead use strip_suffix to take off the ".idx",
record the size of our allocation, and use xsnprintf to make
sure we don't violate our assumptions.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The sha1_to_hex and find_unique_abbrev functions always
write into reusable static buffers. There are a few problems
with this:
- future calls overwrite our result. This is especially
annoying with find_unique_abbrev, which does not have a
ring of buffers, so you cannot even printf() a result
that has two abbreviated sha1s.
- if you want to put the result into another buffer, we
often strcpy, which looks suspicious when auditing for
overflows.
This patch introduces sha1_to_hex_r and find_unique_abbrev_r,
which write into a user-provided buffer. Of course this is
just punting on the overflow-auditing, as the buffer
obviously needs to be GIT_SHA1_HEXSZ + 1 bytes. But it is
much easier to audit, since that is a well-known size.
We retain the non-reentrant forms, which just become thin
wrappers around the reentrant ones. This patch also adds a
strbuf variant of find_unique_abbrev, which will be handy in
later patches.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If you have a function that uses git_path a lot, but would
prefer to avoid the static buffers, it's useful to keep a
single scratch buffer locally and reuse it for each call.
You used to be able to do this with git_snpath:
char buf[PATH_MAX];
foo(git_snpath(buf, sizeof(buf), "foo"));
bar(git_snpath(buf, sizeof(buf), "bar"));
but since 1a83c24, git_snpath has been replaced with
strbuf_git_path. This is good, because it removes the
arbitrary PATH_MAX limit. But using strbuf_git_path is more
awkward for two reasons:
1. It adds to the buffer, rather than replacing it. This
is consistent with other strbuf functions, but makes
reuse of a single buffer more tedious.
2. It doesn't return the buffer, so you can't format
as part of a function's arguments.
The new git_path_buf solves both of these, so you can use it
like:
struct strbuf buf = STRBUF_INIT;
foo(git_path_buf(&buf, "foo"));
bar(git_path_buf(&buf, "bar"));
strbuf_release(&buf);
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When submodule is a linked worktree, "git diff --submodule" and other
calls which directly access the submodule's object database do not correctly
calculate its path. Fix it by changing the git_pathdup_submodule() behavior,
to use either common or per-worktree directory.
Do it similarly as for parent repository, but ignore the GIT_COMMON_DIR
environment variable, because it would mean common directory for the parent
repository and does not make sense for submodule.
Also add test for functionality which uses this call.
Signed-off-by: Max Kirillov <max@max630.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Most of our "--date" modes are about the format of the date:
which items we show and in what order. But "--date=local" is
a bit of an oddball. It means "show the date in the normal
format, but using the local timezone". The timezone we use
is orthogonal to the actual format, and there is no reason
we could not have "localized iso8601", etc.
This patch adds a "local" boolean field to "struct
date_mode", and drops the DATE_LOCAL element from the
date_mode_type enum (it's now just DATE_NORMAL plus
local=1). The new feature is accessible to users by adding
"-local" to any date mode (e.g., "iso-local"), and we retain
"local" as an alias for "default-local" for backwards
compatibility.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The client side codepaths in "git push" have been cleaned up
and the user can request to perform an optional "signed push",
i.e. sign only when the other end accepts signed push.
* db/push-sign-if-asked:
push: add a config option push.gpgSign for default signed pushes
push: support signing pushes iff the server supports it
builtin/send-pack.c: use parse_options API
config.c: rename git_config_maybe_bool_text and export it as git_parse_maybe_bool
transport: remove git_transport_options.push_cert
gitremote-helpers.txt: document pushcert option
Documentation/git-send-pack.txt: document --signed
Documentation/git-send-pack.txt: wrap long synopsis line
Documentation/git-push.txt: document when --signed may fail
Recent reimplementation of "git am" changed the format of state
files kept in $GIT_DIR/rebase-apply/ without meaning to do so,
primarily because write_file() API was cumbersome to use and it was
easy to mistakenly make text files with incomplete lines. Update
write_file() interface to make it harder to misuse.
* jc/am-state-fix:
write_file(): drop caller-supplied LF from calls to create a one-liner file
write_file_v(): do not leave incomplete line at the end
write_file(): drop "fatal" parameter
builtin/am: make sure state files are text
builtin/am: introduce write_state_*() helper functions
Because the configuration system does not allow "alias.0foo" and
"pager.0foo" as the configuration key, the user cannot use '0foo'
as a custom command name anyway, but "git 0foo" tried to look these
keys up and emitted useless warnings before saying '0foo is not a
git command'. These warning messages have been squelched.
* jk/fix-alias-pager-config-key-warnings:
config: silence warnings for command names with invalid keys
All callers except three passed 1 for the "fatal" parameter to ask
this function to die upon error, but to a casual reader of the code,
it was not all obvious what that 1 meant. Instead, split the
function into two based on a common write_file_v() that takes the
flag, introduce write_file_gently() as a new way to attempt creating
a file without dying on error, and make three callers to call it.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we are running the git command "foo", we may have to
look up the config keys "pager.foo" and "alias.foo". These
config schemes are mis-designed, as the command names can be
anything, but the config syntax has some restrictions. For
example:
$ git foo_bar
error: invalid key: pager.foo_bar
error: invalid key: alias.foo_bar
git: 'foo_bar' is not a git command. See 'git --help'.
You cannot name an alias with an underscore. And if you have
an external command with one, you cannot configure its
pager.
In the long run, we may develop a different config scheme
for these features. But in the near term (and because we'll
need to support the existing scheme indefinitely), we should
at least squelch the error messages shown above.
These errors come from git_config_parse_key. Ideally we
would pass a "quiet" flag to the config machinery, but there
are many layers between the pager code and the key parsing.
Passing a flag through all of those would be an invasive
change.
Instead, let's provide a config function to report on
whether a key is syntactically valid, and have the pager and
alias code skip lookup for bogus keys. We can build this
easily around the existing git_config_parse_key, with two
minor modifications:
1. We now handle a NULL store_key, to validate but not
write out the normalized key.
2. We accept a "quiet" flag to avoid writing to stderr.
This doesn't need to be a full-blown public "flags"
field, because we can make the existing implementation
a static helper function, keeping the mess contained
inside config.c.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git_path() and mkpath() are handy helper functions but it is easy
to misuse, as the callers need to be careful to keep the number of
active results below 4. Their uses have been reduced.
* jk/git-path:
memoize common git-path "constant" files
get_repo_path: refactor path-allocation
find_hook: keep our own static buffer
refs.c: remove_empty_directories can take a strbuf
refs.c: avoid git_path assignment in lock_ref_sha1_basic
refs.c: avoid repeated git_path calls in rename_tmp_log
refs.c: simplify strbufs in reflog setup and writing
path.c: drop git_path_submodule
refs.c: remove extra git_path calls from read_loose_refs
remote.c: drop extraneous local variable from migrate_file
prefer mkpathdup to mkpath in assignments
prefer git_pathdup to git_path in some possibly-dangerous cases
add_to_alternates_file: don't add duplicate entries
t5700: modernize style
cache.h: complete set of git_path_submodule helpers
cache.h: clarify documentation for git_path, et al
This helper function does not complain about the config variable
but just silently reports failure to the caller. It is useful for
callers that need to parse any string that could be boolean or other
string (e.g. tristate yes/no/auto).
Signed-off-by: Dave Borowitz <dborowitz@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The hook to report "garbage" files in $GIT_OBJECT_DIRECTORY/pack/
could be generic but is too specific to count-object's needs.
Move the part to produce human-readable messages to count-objects,
and refine the interface to callback with the "bits" with values
defined in the cache.h header file, so that other callers (e.g.
prune) can later use the same mechanism to enumerate different
kinds of garbage files and do something intelligent about them,
other than reporting in textual messages.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
One of the most common uses of git_path() is to pass a
constant, like git_path("MERGE_MSG"). This has two
drawbacks:
1. The return value is a static buffer, and the lifetime
is dependent on other calls to git_path, etc.
2. There's no compile-time checking of the pathname. This
is OK for a one-off (after all, we have to spell it
correctly at least once), but many of these constant
strings appear throughout the code.
This patch introduces a series of functions to "memoize"
these strings, which are essentially globals for the
lifetime of the program. We compute the value once, take
ownership of the buffer, and return the cached value for
subsequent calls. cache.h provides a helper macro for
defining these functions as one-liners, and defines a few
common ones for global use.
Using a macro is a little bit gross, but it does nicely
document the purpose of the functions. If we need to touch
them all later (e.g., because we learned how to change the
git_dir variable at runtime, and need to invalidate all of
the stored values), it will be much easier to have the
complete list.
Note that the shared-global functions have separate, manual
declarations. We could do something clever with the macros
(e.g., expand it to a declaration in some places, and a
declaration _and_ a definition in path.c). But there aren't
that many, and it's probably better to stay away from
too-magical macros.
Likewise, if we abandon the C preprocessor in favor of
generating these with a script, we could get much fancier.
E.g., normalizing "FOO/BAR-BAZ" into "git_path_foo_bar_baz".
But the small amount of saved typing is probably not worth
the resulting confusion to readers who want to grep for the
function's definition.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are no callers of the slightly-dangerous static-buffer
git_path_submodule left. Let's drop it.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The git_path function has "git_pathdup" and
"strbuf_git_path" variants, but git_submodule_path only
comes in the dangerous, static-buffer variant. That makes
refactoring callers to use the safer functions hard (since
they don't exist).
Since we're already using a strbuf behind the scenes, it's
easy to expose all three of these interfaces with thin
wrappers.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The comment above these functions actually describes
sha1_file_name, and comes from the very first revision of
git. Commit 723c31f (Add "git_path()" and "head_ref()"
helper functions., 2005-07-05) added git_path, pushing the
comment away from the function it describes; later commits
added more functions in this block.
Let's fix the comment to describe these related functions in
more detail. Let's also make sure to point out their safer
alternatives (and move those alternatives below, which makes
more sense when reading the file).
Note that we do not need to move the existing comment to
sha1_file_name. Commit d40d535 (sha1_file.c: document a
bunch of functions defined in the file, 2014-02-21) already
added a much more descriptive comment to it.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since 5a688fe4 ("core.sharedrepository = 0mode" should set, not
loosen, 2009-03-25), we kept reminding ourselves:
NEEDSWORK: this should be renamed to finalize_temp_file() as
"moving" is only a part of what it does, when no patch between
master to pu changes the call sites of this function.
without doing anything about it. Let's do so.
The purpose of this function was not to move but to finalize. The
detail of the primarily implementation of finalizing was to link the
temporary file to its final name and then to unlink, which wasn't
even "moving". The alternative implementation did "move" by calling
rename(2), which is a fun tangent.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach "git log" and friends a new "--date=format:..." option to
format timestamps using system's strftime(3).
* jk/date-mode-format:
strbuf: make strbuf_addftime more robust
introduce "format" date-mode
convert "enum date_mode" into a struct
show-branch: use DATE_RELATIVE instead of magic number
Clean up refs API and make "git clone" less intimate with the
implementation detail.
* mh/init-delete-refs-api:
delete_ref(): use the usual convention for old_sha1
cmd_update_ref(): make logic more straightforward
update_ref(): don't read old reference value before delete
check_branch_commit(): make first parameter const
refs.h: add some parameter names to function declarations
refs: move the remaining ref module declarations to refs.h
initial_ref_transaction_commit(): check for ref D/F conflicts
initial_ref_transaction_commit(): check for duplicate refs
refs: remove some functions from the module's public interface
initial_ref_transaction_commit(): function for initial ref creation
repack_without_refs(): make function private
prune_refs(): use delete_refs()
prune_remote(): use delete_refs()
delete_refs(): bail early if the packed-refs file cannot be rewritten
delete_refs(): make error message more generic
delete_refs(): new function for the refs API
delete_ref(): handle special case more explicitly
remove_branches(): remove temporary
delete_ref(): move declaration to refs.h
Replace "is this subdirectory a separate repository that should not
be touched?" check "git clean" does by checking if it has .git/HEAD
using the submodule-related code with a more optimized check.
* ee/clean-remove-dirs:
read_gitfile_gently: fix use-after-free
clean: improve performance when removing lots of directories
p7300: add performance tests for clean
t7300: add tests to document behavior of clean and nested git
setup: sanity check file size in read_gitfile_gently
setup: add gentle version of read_gitfile
Add an environment variable to tell Git to look into refs hierarchy
other than refs/replace/ for the object replacement data.
* mh/replace-refs:
Allow to control where the replace refs are looked for
Disable "have we lost a race with competing repack?" check while
receiving a huge object transfer that runs index-pack.
* jk/index-pack-reduce-recheck:
index-pack: avoid excessive re-reading of pack directory
This feeds the format directly to strftime. Besides being a
little more flexible, the main advantage is that your system
strftime may know more about your locale's preferred format
(e.g., how to spell the days of the week).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In preparation for adding date modes that may carry extra
information beyond the mode itself, this patch converts the
date_mode enum into a struct.
Most of the conversion is fairly straightforward; we pass
the struct as a pointer and dereference the type field where
necessary. Locations that declare a date_mode can use a "{}"
constructor. However, the tricky case is where we use the
enum labels as constants, like:
show_date(t, tz, DATE_NORMAL);
Ideally we could say:
show_date(t, tz, &{ DATE_NORMAL });
but of course C does not allow that. Likewise, we cannot
cast the constant to a struct, because we need to pass an
actual address. Our options are basically:
1. Manually add a "struct date_mode d = { DATE_NORMAL }"
definition to each caller, and pass "&d". This makes
the callers uglier, because they sometimes do not even
have their own scope (e.g., they are inside a switch
statement).
2. Provide a pre-made global "date_normal" struct that can
be passed by address. We'd also need "date_rfc2822",
"date_iso8601", and so forth. But at least the ugliness
is defined in one place.
3. Provide a wrapper that generates the correct struct on
the fly. The big downside is that we end up pointing to
a single global, which makes our wrapper non-reentrant.
But show_date is already not reentrant, so it does not
matter.
This patch implements 3, along with a minor macro to keep
the size of the callers sane.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If this extension is used in a repository, then no
operations should run which may drop objects from the object
storage. This can be useful if you are sharing that storage
with other repositories whose refs you cannot see.
For instance, if you do:
$ git clone -s parent child
$ git -C parent config extensions.preciousObjects true
$ git -C parent config core.repositoryformatversion 1
you now have additional safety when running git in the
parent repository. Prunes and repacks will bail with an
error, and `git gc` will skip those operations (it will
continue to pack refs and do other non-object operations).
Older versions of git, when run in the repository, will
fail on every operation.
Note that we do not set the preciousObjects extension by
default when doing a "clone -s", as doing so breaks
backwards compatibility. It is a decision the user should
make explicitly.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Normally we try to avoid bumps of the whole-repository
core.repositoryformatversion field. However, it is
unavoidable if we want to safely change certain aspects of
git in a backwards-incompatible way (e.g., modifying the set
of ref tips that we must traverse to generate a list of
unreachable, safe-to-prune objects).
If we were to bump the repository version for every such
change, then any implementation understanding version `X`
would also have to understand `X-1`, `X-2`, and so forth,
even though the incompatibilities may be in orthogonal parts
of the system, and there is otherwise no reason we cannot
implement one without the other (or more importantly, that
the user cannot choose to use one feature without the other,
weighing the tradeoff in compatibility only for that
particular feature).
This patch documents the existing repositoryformatversion
strategy and introduces a new format, "1", which lets a
repository specify that it must run with an arbitrary set of
extensions. This can be used, for example:
- to inform git that the objects should not be pruned based
only on the reachability of the ref tips (e.g, because it
has "clone --shared" children)
- that the refs are stored in a format besides the usual
"refs" and "packed-refs" directories
Because we bump to format "1", and because format "1"
requires that a running git knows about any extensions
mentioned, we know that older versions of the code will not
do something dangerous when confronted with these new
formats.
For example, if the user chooses to use database storage for
refs, they may set the "extensions.refbackend" config to
"db". Older versions of git will not understand format "1"
and bail. Versions of git which understand "1" but do not
know about "refbackend", or which know about "refbackend"
but not about the "db" backend, will refuse to run. This is
annoying, of course, but much better than the alternative of
claiming that there are no refs in the repository, or
writing to a location that other implementations will not
read.
Note that we are only defining the rules for format 1 here.
We do not ever write format 1 ourselves; it is a tool that
is meant to be used by users and future extensions to
provide safety with older implementations.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Disable "have we lost a race with competing repack?" check while
receiving a huge object transfer that runs index-pack.
* jk/index-pack-reduce-recheck:
index-pack: avoid excessive re-reading of pack directory
Some functions from the refs module were still declared in cache.h.
Move them to refs.h.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Also
* Add a docstring
* Rename the second parameter to "old_sha1", to be consistent with the
convention used elsewhere in the refs module
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
