refs.c: make ref_transaction_create a wrapper to ref_transaction_update

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs.c: make ref_transaction_delete a wrapper for ref_transaction_update

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs.c: rename the transaction functions

Rename the transaction functions. Remove the leading ref_ from the
names and append _sha1 to the names for functions that create/delete/
update sha1 refs.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs.c: add a new update_type field to ref_update

Add a field that describes what type of update this refers to. For now
the only type is UPDATE_SHA1 but we will soon add more types.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs.c: add a function to append a reflog entry to a fd

Break out the code to create the string and writing it to the file
descriptor from log_ref_write and into a dedicated function log_ref_write_fd.
For now this is only used from log_ref_write but later on we will call
this function from reflog transactions too which means that we will end
up with only a single place where we write a reflog entry to a file instead
of the current two places (log_ref_write and builtin/reflog.c).

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
lockfile.c: make hold_lock_file_for_append preserve meaningful errno

Update hold_lock_file_for_append and copy_fd to return a meaningful errno
on failure.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs.c: add a transaction function to append a reflog entry

Define a new transaction update type, UPDATE_LOG, and a new function
transaction_update_reflog. This function will lock the reflog and append
an entry to it during transaction commit.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs.c: add a flag to allow reflog updates to truncate the log

Add a flag that allows us to truncate the reflog before we write the
update.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs.c: only write reflog update if msg is non-NULL

When performing a reflog transaction update, only write to the reflog iff
msg is non-NULL. This can then be combined with REFLOG_TRUNCATE to perform
an update that only truncates but does not write.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs.c: allow multiple reflog updates during a single transaction

Allow to make multiple reflog updates to the same ref during a transaction.
This means we only need to lock the reflog once, during the first update
that touches the reflog, and that all further updates can just write the
reflog entry since the reflog is already locked.

This allows us to write code such as:

t = transaction_begin()
transaction_reflog_update(t, "foo", REFLOG_TRUNCATE, NULL);
loop-over-somehting...
   transaction_reflog_update(t, "foo", 0, <message>);
transaction_commit(t)

where we first truncate the reflog and then build the new content one line at a
time.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
reflog.c: use a reflog transaction when writing during expire

Use a transaction for all updates during expire_reflog.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs.c: rename log_ref_setup to create_reflog

log_ref_setup is used to do several semi-related things :
* sometimes it will create a new reflog including missing parent directories
  and cleaning up any conflicting stale directories in the path.
* fill in a filename buffer for the full path to the reflog.
* unconditionally re-adjust the permissions for the file.

This function is only called from two places: checkout.c where it is always
used to create a reflog and refs.c:log_ref_write where it sometimes are
used to create a reflog and sometimes just used to fill in the filename.

Rename log_ref_setup to create_reflog and change it to only take the
refname as argument to make its signature similar to delete_reflog and
reflog_exists. Change create_reflog to ignore log_all_ref_updates and
"unconditionally" create the reflog when called. Since checkout.c always
wants to create a reflog we can call create_reflog directly and avoid the
temp-and-log_all_ref_update dance.

In log_ref_write, only call create_reflog iff we want to create a reflog
and if the reflog does not yet exist. This means that for the common case
where the log already exists we now only need to perform a single lstat()
instead of a open(O_CREAT)+lstat()+close().

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs.c: make unlock_ref/close_ref/commit_ref static

unlock|close|commit_ref can be made static since there are no more external
callers.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs.c: remove lock_any_ref_for_update

No one is using this function so we can delete it.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs.c: allow deleting refs with a broken sha1

Add (back?) support to make it possible to delete refs that are broken.

Add a new flag REF_ALLOWBROKEN that can be passed to the functions to
lock a ref. If this flag is set we allow locking the ref even if the
ref points to a broken sha1. For example a sha1 that is created by :

   echo "Broken ref" > .git/refs/heads/foo-broken-1

Use this flag when calling from branch.c dusing a ref delete so that we
only allow locking those broken refs IFF when called during a branch
delete.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
add `config_set` API for caching config-like files

Currently `git_config()` uses a callback mechanism and file rereads for
config values. Due to this approach, it is not uncommon for the config
files to be parsed several times during the run of a git program, with
different callbacks picking out different variables useful to themselves.

Add a `config_set`, that can be used to construct an in-memory cache for
config-like files that the caller specifies (i.e., files like `.gitmodules`,
`~/.gitconfig` etc.). Add two external functions `git_configset_get_value`
and `git_configset_get_value_multi` for querying from the config sets.
`git_configset_get_value` follows `last one wins` semantic (i.e. if there
are multiple matches for the queried key in the files of the configset the
value returned will be the last entry in `value_list`).
`git_configset_get_value_multi` returns a list of values sorted in order of
increasing priority (i.e. last match will be at the end of the list). Add
type specific query functions like `git_configset_get_bool` and similar.

Add a default `config_set`, `the_config_set` to cache all key-value pairs
read from usual config files (repo specific .git/config, user wide
~/.gitconfig, XDG config and the global /etc/gitconfig). `the_config_set`
is populated using `git_config()`.

Add two external functions `git_config_get_value` and
`git_config_get_value_multi` for querying in a non-callback manner from
`the_config_set`. Also, add type specific query functions that are
implemented as a thin wrapper around the `config_set` API.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
test-config: add tests for the config_set API

Expose the `config_set` C API as a set of simple commands in order to
facilitate testing. Add tests for the `config_set` API as well as for
`git_config_get_*()` family for the usual config files.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'hv/submodule-config' into jch

* hv/submodule-config:
  do not die on error of parsing fetchrecursesubmodules option
  use new config API for worktree configurations of submodules
  extract functions for submodule config set and lookup
  implement submodule config cache for lookup of submodule names
Merge branch 'jc/reopen-lock-file' into jch

Needed in the "commit -p" code path to update the cache tree in the
index.

* jc/reopen-lock-file:
  lockfile: allow reopening a closed but still locked file
Merge branch 'dt/cache-tree-repair' into jch

Add a few more places in "commit" and "checkout" that make sure
that the cache-tree is fully populated in the index.

* dt/cache-tree-repair:
  cache-tree: Write updated cache-tree after commit
  cache-tree: subdirectory tests
  test-dump-cache-tree: invalid trees are not errors
  cache-tree: create/update cache-tree on checkout

# Conflicts:
# 	builtin/checkout.c
# 	builtin/commit.c