Plumb "struct key_value_info" through all code paths that end in
die_bad_number(), which lets us remove the helper functions that read
analogous values from "struct config_reader". As a result, nothing reads
config_reader.config_kvi any more, so remove that too.
In config.c, this requires changing the signature of
git_configset_get_value() to 'return' "kvi" in an out parameter so that
git_configset_get_<type>() can pass it to git_config_<type>(). Only
numeric types will use "kvi", so for non-numeric types (e.g.
git_configset_get_string()), pass NULL to indicate that the out
parameter isn't needed.
Outside of config.c, config callbacks now need to pass "ctx->kvi" to any
of the git_config_<type>() functions that parse a config string into a
number type. Included is a .cocci patch to make that refactor.
The only exceptional case is builtin/config.c, where git_config_<type>()
is called outside of a config callback (namely, on user-provided input),
so config source information has never been available. In this case,
die_bad_number() defaults to a generic, but perfectly descriptive
message. Let's provide a safe, non-NULL for "kvi" anyway, but make sure
not to change the message.
Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
These defines and enum are all oid-related and as such seem to make
more sense being included in hash.h. Further, moving them there
allows us to remove some includes of cache.h in other files.
The change to line-log.h might look unrelated, but line-log.h includes
diffcore.h, which previously included cache.h, which included the
kitchen sink. Since this patch makes diffcore.h no longer include
cache.h, the compiler complains about the 'struct string_list *'
function parameter. Add a forward declaration for struct string_list to
address this.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Using a named enum allows casting an integer to the enum type in both
GDB and LLDB:
$ gdb -q -ex 'b wt-status.c:44' -ex r --args ./git status
(gdb) p (enum color_wt_status) slot
$1 = WT_STATUS_ONBRANCH
$ lldb -o 'b wt-status.c:44' -o r -- ./git status
(lldb) p (color_wt_status) slot
(color_wt_status) $0 = WT_STATUS_ONBRANCH
In LLDB, it's also required to cast in the reversed direction, i.e.
cast an enum constant into its corresponding integer:
(lldb) p (int) color_wt_status::WT_STATUS_ONBRANCH
(int) $1 = 8
Name the enum listing the different RECURSE_SUBMODULES_* modes, to make
debugging easier. For example, when stepping through a part of the code
where an int is compared with a constant in this enum, it allows casting
the int to the enum type or vice-versa, after quickly checking where the
enum constant is declared and learning the enum name.
As to not make this patch a debug-only change, convert the
'fetch_recurse' member of 'struct submodule' to use the newly named
enum.
Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com>
Reviewed-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To improve the submodules UX, we would like to teach Git to handle
branches in submodules. Start this process by teaching "git branch" the
--recurse-submodules option so that "git branch --recurse-submodules
topic" will create the `topic` branch in the superproject and its
submodules.
Although this commit does not introduce breaking changes, it does not
work well with existing --recurse-submodules commands because "git
branch --recurse-submodules" writes to the submodule ref store, but most
commands only consider the superproject gitlink and ignore the submodule
ref store. For example, "git checkout --recurse-submodules" will check
out the commits in the superproject gitlinks (and put the submodules in
detached HEAD) instead of checking out the submodule branches.
Because of this, this commit introduces a new configuration value,
`submodule.propagateBranches`. The plan is for Git commands to
prioritize submodule ref store information over superproject gitlinks if
this value is true. Because "git branch --recurse-submodules" writes to
submodule ref stores, for the sake of clarity, it will not function
unless this configuration value is set.
This commit also includes changes that support working with submodules
from a superproject commit because "branch --recurse-submodules" (and
future commands) need to read .gitmodules and gitlinks from the
superproject commit, but submodules are typically read from the
filesystem's .gitmodules and the index's gitlinks. These changes are:
* add a submodules_of_tree() helper that gives the relevant
information of an in-tree submodule (e.g. path and oid) and
initializes the repository
* add is_tree_submodule_active() by adding a treeish_name parameter to
is_submodule_active()
* add the "submoduleNotUpdated" advice to advise users to update the
submodules in their trees
Incidentally, fix an incorrect usage string that combined the 'list'
usage of git branch (-l) with the 'create' usage; this string has been
incorrect since its inception, a8dfd5eac4 (Make builtin-branch.c use
parse_options., 2007-10-07).
Helped-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Glen Choo <chooglen@google.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This macro was added and used in c68f837576 (implement fetching of
moved submodules, 2017-10-16) but its last user went away in
be76c21282 (fetch: ensure submodule objects fetched, 2018-12-06).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently, submodule-config.c doesn't have an externally accessible
function to read gitmodules only if it wasn't already read. But this
exact behavior is internally implemented by gitmodules_read_check(), to
perform a lazy load. Let's merge this function with
repo_read_gitmodules() adding a 'skip_if_read' which allows both
internal and external callers to access this functionality. This
simplifies a little the code. The added option will also be used in
the following patch.
Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move the documentation from Documentation/technical/api-submodule-config.txt
to submodule-config.h as it's easier for the developers to find the usage
information beside the code instead of looking for it in another doc file.
Documentation/technical/api-submodule-config.txt is removed because the
information it has is now redundant and it'll be hard to keep it up to
date and synchronized with the documentation in the header file.
The documentation of parse_submodule_config_option() is discarded as the
function was removed 2 years ago.
Signed-off-by: Heba Waly <heba.waly@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In previous patches, extern was mechanically removed from function
declarations without care to formatting, causing parameter lists to be
misaligned. Manually format changed sections such that the parameter
lists should be realigned.
Viewing this patch with 'git diff -w' should produce no output.
Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There has been a push to remove extern from function declarations.
Remove some instances of "extern" for function declarations which are
caught by Coccinelle. Note that Coccinelle has some difficulty with
processing functions with `__attribute__` or varargs so some `extern`
declarations are left behind to be dealt with in a future patch.
This was the Coccinelle patch used:
@@
type T;
identifier f;
@@
- extern
T f(...);
and it was run with:
$ git ls-files \*.{c,h} |
grep -v ^compat/ |
xargs spatch --sp-file contrib/coccinelle/noextern.cocci --in-place
Files under `compat/` are intentionally excluded as some are directly
copied from external sources and we should avoid churning them as much
as possible.
Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new config_set_in_gitmodules_file_gently() function to write
config values to the .gitmodules file.
This is in preparation for a future change which will use the function
to write to the .gitmodules file in a more controlled way instead of
using "git config -f .gitmodules".
The purpose of the change is mainly to centralize the code that writes
to the .gitmodules file to avoid some duplication.
The naming follows git_config_set_in_file_gently() but the git_ prefix
is removed to communicate that this is not a generic git-config API.
Signed-off-by: Antonio Ospite <ao2@ao2.it>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a new print_config_from_gitmodules() helper function to print values
from .gitmodules just like "git config -f .gitmodules" would.
This will be used by a new submodule--helper subcommand to be able to
access the .gitmodules file in a more controlled way.
Signed-off-by: Antonio Ospite <ao2@ao2.it>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that 'config_from_gitmodules' is not used in the open, it can be
marked as private.
Hopefully this will prevent its usage for retrieving arbitrary
configuration form the '.gitmodules' file.
Signed-off-by: Antonio Ospite <ao2@ao2.it>
Acked-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a helper function to make it clearer that retrieving 'update-clone'
configuration from the .gitmodules file is a special case supported
solely for backward compatibility purposes.
This change removes one direct use of 'config_from_gitmodules' for
options not strictly related to submodules: "submodule.fetchjobs" does
not describe a property of a submodule, but a behavior of other commands
when dealing with submodules, so it does not really belong to the
.gitmodules file.
This is in the effort to communicate better that .gitmodules is not to
be used as a mechanism to store arbitrary configuration in the
repository that any command can retrieve.
Signed-off-by: Antonio Ospite <ao2@ao2.it>
Acked-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a helper function to make it clearer that retrieving 'fetch'
configuration from the .gitmodules file is a special case supported
solely for backward compatibility purposes.
This change removes one direct use of 'config_from_gitmodules' in code
not strictly related to submodules, in the effort to communicate better
that .gitmodules is not to be used as a mechanism to store arbitrary
configuration in the repository that any command can retrieve.
Signed-off-by: Antonio Ospite <ao2@ao2.it>
Acked-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The .gitmodules file is not meant as a place to store arbitrary
configuration to distribute with the repository.
Move config_from_gitmodules() out of config.c and into
submodule-config.c to make it even clearer that it is not a mechanism to
retrieve arbitrary configuration from the .gitmodules file.
Signed-off-by: Antonio Ospite <ao2@ao2.it>
Acked-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Conversion from uchar[20] to struct object_id continues.
* bc/object-id: (42 commits)
merge-one-file: compute empty blob object ID
add--interactive: compute the empty tree value
Update shell scripts to compute empty tree object ID
sha1_file: only expose empty object constants through git_hash_algo
dir: use the_hash_algo for empty blob object ID
sequencer: use the_hash_algo for empty tree object ID
cache-tree: use is_empty_tree_oid
sha1_file: convert cached object code to struct object_id
builtin/reset: convert use of EMPTY_TREE_SHA1_BIN
builtin/receive-pack: convert one use of EMPTY_TREE_SHA1_HEX
wt-status: convert two uses of EMPTY_TREE_SHA1_HEX
submodule: convert several uses of EMPTY_TREE_SHA1_HEX
sequencer: convert one use of EMPTY_TREE_SHA1_HEX
merge: convert empty tree constant to the_hash_algo
builtin/merge: switch tree functions to use object_id
builtin/am: convert uses of EMPTY_TREE_SHA1_BIN to the_hash_algo
sha1-file: add functions for hex empty tree and blob OIDs
builtin/receive-pack: avoid hard-coded constants for push certs
diff: specify abbreviation size in terms of the_hash_algo
upload-pack: replace use of several hard-coded constants
...
* maint-2.15:
Git 2.15.2
Git 2.14.4
Git 2.13.7
verify_path: disallow symlinks in .gitmodules
update-index: stat updated files earlier
verify_dotfile: mention case-insensitivity in comment
verify_path: drop clever fallthrough
skip_prefix: add case-insensitive variant
is_{hfs,ntfs}_dotgitmodules: add tests
is_ntfs_dotgit: match other .git files
is_hfs_dotgit: match other .git files
is_ntfs_dotgit: use a size_t for traversing string
submodule-config: verify submodule names as paths
* maint-2.14:
Git 2.14.4
Git 2.13.7
verify_path: disallow symlinks in .gitmodules
update-index: stat updated files earlier
verify_dotfile: mention case-insensitivity in comment
verify_path: drop clever fallthrough
skip_prefix: add case-insensitive variant
is_{hfs,ntfs}_dotgitmodules: add tests
is_ntfs_dotgit: match other .git files
is_hfs_dotgit: match other .git files
is_ntfs_dotgit: use a size_t for traversing string
submodule-config: verify submodule names as paths
* maint-2.13:
Git 2.13.7
verify_path: disallow symlinks in .gitmodules
update-index: stat updated files earlier
verify_dotfile: mention case-insensitivity in comment
verify_path: drop clever fallthrough
skip_prefix: add case-insensitive variant
is_{hfs,ntfs}_dotgitmodules: add tests
is_ntfs_dotgit: match other .git files
is_hfs_dotgit: match other .git files
is_ntfs_dotgit: use a size_t for traversing string
submodule-config: verify submodule names as paths
Submodule "names" come from the untrusted .gitmodules file,
but we blindly append them to $GIT_DIR/modules to create our
on-disk repo paths. This means you can do bad things by
putting "../" into the name (among other things).
Let's sanity-check these names to avoid building a path that
can be exploited. There are two main decisions:
1. What should the allowed syntax be?
It's tempting to reuse verify_path(), since submodule
names typically come from in-repo paths. But there are
two reasons not to:
a. It's technically more strict than what we need, as
we really care only about breaking out of the
$GIT_DIR/modules/ hierarchy. E.g., having a
submodule named "foo/.git" isn't actually
dangerous, and it's possible that somebody has
manually given such a funny name.
b. Since we'll eventually use this checking logic in
fsck to prevent downstream repositories, it should
be consistent across platforms. Because
verify_path() relies on is_dir_sep(), it wouldn't
block "foo\..\bar" on a non-Windows machine.
2. Where should we enforce it? These days most of the
.gitmodules reads go through submodule-config.c, so
I've put it there in the reading step. That should
cover all of the C code.
We also construct the name for "git submodule add"
inside the git-submodule.sh script. This is probably
not a big deal for security since the name is coming
from the user anyway, but it would be polite to remind
them if the name they pick is invalid (and we need to
expose the name-checker to the shell anyway for our
test scripts).
This patch issues a warning when reading .gitmodules
and just ignores the related config entry completely.
This will generally end up producing a sensible error,
as it works the same as a .gitmodules file which is
missing a submodule entry (so "submodule update" will
barf, but "git clone --recurse-submodules" will print
an error but not abort the clone.
There is one minor oddity, which is that we print the
warning once per malformed config key (since that's how
the config subsystem gives us the entries). So in the
new test, for example, the user would see three
warnings. That's OK, since the intent is that this case
should never come up outside of malicious repositories
(and then it might even benefit the user to see the
message multiple times).
Credit for finding this vulnerability and the proof of
concept from which the test script was adapted goes to
Etienne Stalmans.
Signed-off-by: Jeff King <peff@peff.net>
Convert struct submodule and struct parse_config_parameter to use struct
object_id. Adjust the functions which take members of these structures
as arguments to also use struct object_id. Include cache.h into
submodule-config.h to make struct object_id visible.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This continues the story of bf12fcdf5e (submodule-config: store
the_submodule_cache in the_repository, 2017-06-22).
The previous patch taught submodule_from_path to take a repository into
account, such that submodule_from_{path, cache} are the same now.
Remove submodule_from_cache, migrating all its callers to
submodule_from_path.
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This enables submodule_from_{name, path} to handle arbitrary repositories.
All callers just pass in the_repository, a later patch will pass in other
repos.
While at it remove the extern key word from the declarations.
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
At some point we may want to rename the function so that it describes what
it actually does as 'submodule_free' doesn't quite describe that this
clears a repository's submodule cache. But that's beyond the scope of
this series.
While at it remove the extern key word from its declaration.
Signed-off-by: Stefan Beller <sbeller@google.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We store the changed submodules paths to calculate which submodule needs
fetching. This does not work for moved submodules since their paths do
not stay the same in case of a moved submodules. In case of new
submodules we do not have a path in the current checkout, since they
just appeared in this fetch.
It is more general to collect the submodule names for changes instead of
their paths to include the above cases. If we do not have a
configuration for a gitlink we rely on constructing a default name from
the path if a git repository can be found at its path. We skip
non-configured gitlinks whose default name collides with a configured
one.
With the change described above we implement 'on-demand' fetching of
changes in moved submodules.
Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Migrate the functions used to initialize the submodule-config to
submodule-config.c so that the callback routine used in the
initialization process can be static and prevent it from being used
outside of initializing the submodule-config through the main API.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
All callers have been migrated to explicitly read any configuration they
need. The support for handling it automatically in submodule-config is
no longer needed.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* bc/object-id:
sha1_name: convert uses of 40 to GIT_SHA1_HEXSZ
sha1_name: convert GET_SHA1* flags to GET_OID*
sha1_name: convert get_sha1* to get_oid*
Convert remaining callers of get_sha1 to get_oid.
builtin/unpack-file: convert to struct object_id
bisect: convert bisect_checkout to struct object_id
builtin/update_ref: convert to struct object_id
sequencer: convert to struct object_id
remote: convert struct push_cas to struct object_id
submodule: convert submodule config lookup to use object_id
builtin/merge-tree: convert remaining caller of get_sha1 to object_id
builtin/fsck: convert remaining caller of get_sha1 to object_id
tag: convert gpg_verify_tag to use struct object_id
commit: convert lookup_commit_graft to struct object_id
The '.gitmodules' file should only contain information pertinent to
configuring individual submodules (name to path mapping, URL where to
obtain the submodule, etc.) while other configuration like the number of
jobs to use when fetching submodules should be a part of the
repository's config.
Remove the 'submodule.fetchjobs' configuration option from the general
submodule-config parsing and instead rely on using the
'config_from_gitmodules()' in order to maintain backwards compatibility
with this config being placed in the '.gitmodules' file.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git pull --rebase --recurse-submodules" learns to rebase the
branch in the submodules to an updated base.
* sb/pull-rebase-submodule:
builtin/fetch cleanup: always set default value for submodule recursing
pull: optionally rebase submodules (remote submodule changes only)
builtin/fetch: parse recurse-submodules-default at default options parsing
builtin/fetch: factor submodule recurse parsing out to submodule config
Refactor how 'the_submodule_cache' is handled so that it can be stored
inside of a repository object. Also migrate 'the_submodule_cache' to be
stored in 'the_repository'.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Later we want to access this parsing in builtin/pull as well.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Similar to b33a15b08 (push: add recurseSubmodules config option,
2015-11-17) and 027771fcb1 (submodule: allow erroneous values for the
fetchRecurseSubmodules option, 2015-08-17), we add submodule-config code
that is later used to parse whether we are interested in updating
submodules.
We need the `die_on_error` parameter to be able to call this parsing
function for the config file as well, which if incorrect lets Git die.
As we're just touching the header file, also mark all functions extern.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git grep" has been taught to optionally recurse into submodules.
* bw/grep-recurse-submodules:
grep: search history of moved submodules
grep: enable recurse-submodules to work on <tree> objects
grep: optionally recurse into submodules
grep: add submodules as a grep source type
submodules: load gitmodules file from commit sha1
submodules: add helper to determine if a submodule is initialized
submodules: add helper to determine if a submodule is populated
real_path: canonicalize directory separators in root parts
real_path: have callers use real_pathdup and strbuf_realpath
real_path: create real_pathdup
real_path: convert real_path_internal to strbuf_realpath
real_path: resolve symlinks by hand
teach submodules to load a '.gitmodules' file from a commit sha1. This
enables the population of the submodule_cache to be based on the state
of the '.gitmodules' file from a particular commit.
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is also possible to pass in any treeish name to lookup a submodule
config. Make it clear by naming the variables accordingly. Looking up
a submodule config by tree hash will come in handy in a later patch.
Signed-off-by: Stefan Beller <sbeller@google.com>
Reviewed-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The branch field will be used in a later patch by `submodule update`.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The shallow field will be used in a later patch by `submodule update`.
To differentiate between the actual depth (which may be different),
we name it `recommend_shallow` as the field in the .gitmodules file
is only a recommendation by the project.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A major part of "git submodule update" has been ported to C to take
advantage of the recently added framework to run download tasks in
parallel.
* sb/submodule-parallel-update:
clone: allow an explicit argument for parallel submodule clones
submodule update: expose parallelism to the user
submodule helper: remove double 'fatal: ' prefix
git submodule update: have a dedicated helper for cloning
run_processes_parallel: rename parameters for the callbacks
run_processes_parallel: treat output of children as byte array
submodule update: direct error message to stderr
fetching submodules: respect `submodule.fetchJobs` config option
submodule-config: drop check against NULL
submodule-config: keep update strategy around
Currently submodule.<name>.update is only handled by git-submodule.sh.
C code will start to need to make use of that value as more of the
functionality of git-submodule.sh moves into library code in C.
Add the update field to 'struct submodule' and populate it so it can
be read as sm->update or from sm->update_command.
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The --recurse-submodules command line parameter has existed for some
time but it has no config file equivalent.
Following the style of the corresponding parameter for git fetch, let's
invent push.recurseSubmodules to provide a default for this
parameter. This also requires the addition of --recurse-submodules=no to
allow the configuration to be overridden on the command line when
required.
The most straightforward way to implement this appears to be to make
push use code in submodule-config in a similar way to fetch.
Signed-off-by: Mike Crowe <mac@mcrowe.com>
Signed-off-by: Jeff King <peff@peff.net>
We should not die when reading the submodule config cache since the
user might not be able to get out of that situation when the
configuration is part of the history.
We should handle this condition later when the value is about to be
used.
Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We remove the extracted functions and directly parse into and read out
of the cache. This allows us to have one unified way of accessing
submodule configuration values specific to single submodules. Regardless
whether we need to access a configuration from history or from the
worktree.
Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a superproject some commands need to interact with submodules. They
need to query values from the .gitmodules file either from the worktree
of from certain revisions. At the moment this is quite hard since a
caller would need to read the .gitmodules file from the history and then
parse the values. We want to provide an API for this so we have one
place to get values from .gitmodules from any revision (including the
worktree).
The API is realized as a cache which allows us to lazily read
.gitmodules configurations by commit into a runtime cache which can then
be used to easily lookup values from it. Currently only the values for
path or name are stored but it can be extended for any value needed.
It is expected that .gitmodules files do not change often between
commits. Thats why we lookup the .gitmodules sha1 from a commit and then
either lookup an already parsed configuration or parse and cache an
unknown one for each sha1. The cache is lazily build on demand for each
requested commit.
This cache can be used for all purposes which need knowledge about
submodule configurations. Example use cases are:
* Recursive submodule checkout needs to lookup a submodule name from
its path when a submodule first appears. This needs be done before
this configuration exists in the worktree.
* The implementation of submodule support for 'git archive' needs to
lookup the submodule name to generate the archive when given a
revision that is not checked out.
* 'git fetch' when given the --recurse-submodules=on-demand option (or
configuration) needs to lookup submodule names by path from the
database rather than reading from the worktree. For new submodule it
needs to lookup the name from its path to allow cloning new
submodules into the .git folder so they can be checked out without
any network interaction when the user does a checkout of that
revision.
Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
