Now that the packed reference store supports transactions, we can use
a transaction to write the packed versions of references that we want
to pack. This decreases the coupling between `files_ref_store` and
`packed_ref_store`.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Implement `packed_delete_refs()` using a reference transaction. This
means that `files_delete_refs()` can use `refs_delete_refs()` instead
of `repack_without_refs()` to delete any packed references, decreasing
the coupling between the classes.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Implement the methods needed to support reference transactions for
the packed-refs backend. The new methods are not yet used.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

`packed_ref_store` is going to want to store some transaction-wide
data, so make a place for it.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The old code incremented the packed ref cache reference count when
acquiring the packed-refs lock, and decremented the count when
releasing the lock. This is unnecessary because:

* Another process cannot change the packed-refs file because it is
  locked.

* When we ourselves change the packed-refs file, we do so by first
  modifying the packed ref-cache, and then writing the data from the
  ref-cache to disk. So the packed ref-cache remains fresh because any
  changes that we plan to make to the file are made in the cache first
  anyway.

So there is no reason for the cache to become stale.

Moreover, the extra reference count causes a problem if we
intentionally clear the packed refs cache, as we sometimes need to do
if we change the cache in anticipation of writing a change to disk,
but then the write to disk fails. In that case, `packed_refs_unlock()`
would have no easy way to find the cache whose reference count it
needs to decrement.

This whole issue will soon become moot due to upcoming changes that
avoid changing the in-memory cache as part of updating the packed-refs
on disk, but this change makes that transition easier.
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Killing "git merge --edit" before the editor returns control left
the repository in a state with MERGE_MSG but without MERGE_HEAD,
which incorrectly tells the subsequent "git commit" that there was
a squash merge in progress.  This has been fixed.

* mg/killed-merge:
  merge: save merge state earlier
  merge: split write_merge_state in two
  merge: clarify call chain
  Documentation/git-merge: explain --continue

Code movement to make it easier to hack later.

* jt/packmigrate: (23 commits)
  pack: move for_each_packed_object()
  pack: move has_pack_index()
  pack: move has_sha1_pack()
  pack: move find_pack_entry() and make it global
  pack: move find_sha1_pack()
  pack: move find_pack_entry_one(), is_pack_valid()
  pack: move check_pack_index_ptr(), nth_packed_object_offset()
  pack: move nth_packed_object_{sha1,oid}
  pack: move clear_delta_base_cache(), packed_object_info(), unpack_entry()
  pack: move unpack_object_header()
  pack: move get_size_from_delta()
  pack: move unpack_object_header_buffer()
  pack: move {,re}prepare_packed_git and approximate_object_count
  pack: move install_packed_git()
  pack: move add_packed_git()
  pack: move unuse_pack()
  pack: move use_pack()
  pack: move pack-closing functions
  pack: move release_pack_memory()
  pack: move open_pack_index(), parse_pack_index()
  ...

The code to acquire a lock on a reference (e.g. while accepting a
push from a client) used to immediately fail when the reference is
already locked---now it waits for a very short while and retries,
which can make it succeed if the lock holder was holding it during
a read-only operation.

* mh/ref-lock-entry:
  refs: retry acquiring reference locks for 100ms

Doc updates.

* jt/doc-pack-objects-fix:
  Doc: clarify that pack-objects makes packs, plural

"[gc] rerereResolved = 5.days" used to be invalid, as the variable
is defined to take an integer counting the number of days.  It now
is allowed.

* jc/cutoff-config:
  rerere: allow approxidate in gc.rerereResolved/gc.rerereUnresolved
  rerere: represent time duration in timestamp_t internally
  t4200: parameterize "rerere gc" custom expiry test
  t4200: gather "rerere gc" together
  t4200: make "rerere gc" test more robust
  t4200: give us a clean slate after "rerere gc" tests

We used to spend more than necessary cycles allocating and freeing
piece of memory while writing each index entry out.  This has been
optimized.

* kw/write-index-reduce-alloc:
  read-cache: avoid allocating every ondisk entry when writing
  read-cache: fix memory leak in do_write_index
  perf: add test for writing the index

Code clean-up to avoid mixing values read from the .gitmodules file
and values read from the .git/config file.

* bw/submodule-config-cleanup:
  submodule: remove gitmodules_config
  unpack-trees: improve loading of .gitmodules
  submodule-config: lazy-load a repository's .gitmodules file
  submodule-config: move submodule-config functions to submodule-config.c
  submodule-config: remove support for overlaying repository config
  diff: stop allowing diff to have submodules configured in .git/config
  submodule: remove submodule_config callback routine
  unpack-trees: don't respect submodule.update
  submodule: don't rely on overlayed config when setting diffopts
  fetch: don't overlay config with submodule-config
  submodule--helper: don't overlay config in update-clone
  submodule--helper: don't overlay config in remote_submodule_branch
  add, reset: ensure submodules can be added or reset
  submodule: don't use submodule_from_name
  t7411: check configuration parsing errors

"gitweb" shows a link to visit the 'raw' contents of blbos in the
history overview page.

* js/gitweb-raw-blob-link-in-history:
  gitweb: add 'raw' blob_plain link in history overview

* po/object-id:
  sha1_file: convert index_stream to struct object_id
  sha1_file: convert hash_sha1_file_literally to struct object_id
  sha1_file: convert index_fd to struct object_id
  sha1_file: convert index_path to struct object_id
  read-cache: convert to struct object_id
  builtin/hash-object: convert to struct object_id

Code clean-up.

* jn/vcs-svn-cleanup:
  vcs-svn: move remaining repo_tree functions to fast_export.h
  vcs-svn: remove repo_delete wrapper function
  vcs-svn: remove custom mode constants
  vcs-svn: remove more unused prototypes and declarations

Code clean-up.

* bc/vcs-svn-cleanup:
  vcs-svn: rename repo functions to "svn_repo"
  vcs-svn: remove unused prototypes

"git apply" that is used as a better "patch -p1" failed to apply a
taken from a file with CRLF line endings to a file with CRLF line
endings.  The root cause was because it misused convert_to_git()
that tried to do "safe-crlf" processing by looking at the index
entry at the same path, which is a nonsense---in that mode, "apply"
is not working on the data in (or derived from) the index at all.
This has been fixed.

* tb/apply-with-crlf:
  apply: file commited with CRLF should roundtrip diff and apply
  convert: add SAFE_CRLF_KEEP_CRLF

Test update to improve coverage for "git stash" operations.

* jt/stash-tests:
  stash: add a test for stashing in a detached state
  stash: add a test for when apply fails during stash branch
  stash: add a test for stash create with no files

"git interpret-trailers" has been taught a "--parse" and a few
other options to make it easier for scripts to grab existing
trailer lines from a commit log message.

* jk/trailers-parse:
  doc/interpret-trailers: fix "the this" typo
  pretty: support normalization options for %(trailers)
  t4205: refactor %(trailers) tests
  pretty: move trailer formatting to trailer.c
  interpret-trailers: add --parse convenience option
  interpret-trailers: add an option to unfold values
  interpret-trailers: add an option to show only existing trailers
  interpret-trailers: add an option to show only the trailers
  trailer: put process_trailers() options into a struct

"git interpret-trailers" learned to take the trailer specifications
from the command line that overrides the configured values.

* pb/trailers-from-command-line:
  interpret-trailers: fix documentation typo
  interpret-trailers: add options for actions
  trailers: introduce struct new_trailer_item
  trailers: export action enums and corresponding lookup functions

A handful of bugfixes and an improvement to "diff --color-moved".

* jt/diff-color-move-fix:
  diff: define block by number of alphanumeric chars
  diff: respect MIN_BLOCK_LENGTH for last block
  diff: avoid redundantly clearing a flag

"git diff" has been taught to optionally paint new lines that are
the same as deleted lines elsewhere differently from genuinely new
lines.

* sb/diff-color-move: (25 commits)
  diff: document the new --color-moved setting
  diff.c: add dimming to moved line detection
  diff.c: color moved lines differently, plain mode
  diff.c: color moved lines differently
  diff.c: buffer all output if asked to
  diff.c: emit_diff_symbol learns about DIFF_SYMBOL_SUMMARY
  diff.c: emit_diff_symbol learns about DIFF_SYMBOL_STAT_SEP
  diff.c: convert word diffing to use emit_diff_symbol
  diff.c: convert show_stats to use emit_diff_symbol
  diff.c: convert emit_binary_diff_body to use emit_diff_symbol
  submodule.c: migrate diff output to use emit_diff_symbol
  diff.c: emit_diff_symbol learns DIFF_SYMBOL_REWRITE_DIFF
  diff.c: emit_diff_symbol learns about DIFF_SYMBOL_BINARY_FILES
  diff.c: emit_diff_symbol learns DIFF_SYMBOL_HEADER
  diff.c: emit_diff_symbol learns DIFF_SYMBOL_FILEPAIR_{PLUS, MINUS}
  diff.c: emit_diff_symbol learns DIFF_SYMBOL_CONTEXT_INCOMPLETE
  diff.c: emit_diff_symbol learns DIFF_SYMBOL_WORDS[_PORCELAIN]
  diff.c: migrate emit_line_checked to use emit_diff_symbol
  diff.c: emit_diff_symbol learns DIFF_SYMBOL_NO_LF_EOF
  diff.c: emit_diff_symbol learns DIFF_SYMBOL_CONTEXT_FRAGINFO
  ...

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Doc clean-up.

* jk/doc-the-this:
  doc: fix typo in sendemail.identity

Code clean-up.

* rs/commit-h-single-parent-cleanup:
  commit: remove unused inline function single_parent()

The API to start showing progress meter after a short delay has
been simplified.

* jc/simplify-progress:
  progress: simplify "delayed" progress API

Updates to the HTTP layer we made recently unconditionally used
features of libCurl without checking the existence of them, causing
compilation errors, which has been fixed.  Also migrate the code to
check feature macros, not version numbers, to cope better with
libCurl that vendor ships with backported features.

* tc/curl-with-backports:
  http: use a feature check to enable GSSAPI delegation control
  http: fix handling of missing CURLPROTO_*

When handshake with a subprocess filter notices that the process
asked for an unknown capability, Git did not report what program
the offending subprocess was running.  This has been corrected.

* cc/subprocess-handshake-missing-capabilities:
  sub-process: print the cmd when a capability is unsupported

Conversion from uchar[20] to struct object_id continues.

* rs/object-id:
  tree-walk: convert fill_tree_descriptor() to object_id

"git merge" learned a "--signoff" option to add the Signed-off-by:
trailer with the committer's name.

* lg/merge-signoff:
  merge: add a --signoff flag

Signed-off-by: NJonathan Tan <jonathantanmy@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJonathan Tan <jonathantanmy@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJonathan Tan <jonathantanmy@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This function needs to be global as it is used by sha1_file.c and will
be used by packfile.c.
Signed-off-by: NJonathan Tan <jonathantanmy@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJonathan Tan <jonathantanmy@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJonathan Tan <jonathantanmy@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJonathan Tan <jonathantanmy@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJonathan Tan <jonathantanmy@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Both sha1_file.c and packfile.c now need read_object(), so a copy of
read_object() was created in packfile.c.

This patch makes both mark_bad_packed_object() and has_packed_and_bad()
global. Unlike most of the other patches in this series, these 2
functions need to remain global.
Signed-off-by: NJonathan Tan <jonathantanmy@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>