Doc update.

* cw/protocol-v2-doc-fix:
  protocol-v2.txt: align delim-pkt spec with usage

Ensure that the sparseness of the in-core index matches the
index.sparse configuration specified by the repository immediately
after the on-disk index file is read.

* vd/sparse-sparsity-fix-on-read:
  sparse-index: update do_read_index to ensure correct sparsity
  sparse-index: add ensure_correct_sparsity function
  sparse-index: avoid unnecessary cache tree clearing
  test-read-cache.c: prepare_repo_settings after config init

Code clean-up to eventually allow information on remotes defined
for an arbitrary repository to be read.

* gc/remote-with-fewer-static-global-variables:
  remote: die if branch is not found in repository
  remote: remove the_repository->remote_state from static methods
  remote: use remote_state parameter internally
  remote: move static variables into per-repository struct
  t5516: add test case for pushing remote refspecs

Doc update.

* ja/doc-cleanup:
  init doc: --shared=0xxx does not give umask but perm bits
  doc: git-init: clarify file modes in octal.
  doc: git-http-push: describe the refs as pattern pairs
  doc: uniformize <URL> placeholders' case
  doc: use three dots for indicating repetition instead of star
  doc: git-ls-files: express options as optional alternatives
  doc: use only hyphens as word separators in placeholders
  doc: express grammar placeholders between angle brackets
  doc: split placeholders as individual tokens
  doc: fix git credential synopsis

Redact the path part of packfile URI that appears in the trace output.

* if/redact-packfile-uri:
  http-fetch: redact url on die() message
  fetch-pack: redact packfile urls in traces

Doc update.

* jc/fix-first-object-walk:
  docs: add headers in MyFirstObjectWalk
  docs: fix places that break compilation in MyFirstObjectWalk

CI has been taught to catch some Unicode directional formatting
sequence that can be used in certain mischief.

* js/ci-no-directional-formatting:
  ci: disallow directional formatting

The "--date=format:<strftime>" gained a workaround for the lack of
system support for a non-local timezone to handle "%s" placeholder.

* jk/strbuf-addftime-seconds-since-epoch:
  strbuf_addftime(): handle "%s" manually

"git var GIT_DEFAULT_BRANCH" is a way to see what name is used for
the newly created branch if "git init" is run.

* tw/var-default-branch:
  var: add GIT_DEFAULT_BRANCH variable

Build optimization.

* ab/generate-command-list:
  generate-cmdlist.sh: don't parse command-list.txt thrice
  generate-cmdlist.sh: replace "grep' invocation with a shell version
  generate-cmdlist.sh: do not shell out to "sed"
  generate-cmdlist.sh: stop sorting category lines
  generate-cmdlist.sh: replace for loop by printf's auto-repeat feature
  generate-cmdlist.sh: run "grep | sort", not "sort | grep"
  generate-cmdlist.sh: don't call get_categories() from category_list()
  generate-cmdlist.sh: spawn fewer processes
  generate-cmdlist.sh: trivial whitespace change
  command-list.txt: sort with "LC_ALL=C sort"

Tighten code for testing pack-bitmap.

* jk/test-bitmap-fix:
  test_bitmap_hashes(): handle repository without bitmaps

The "merge" subcommand of "git jump" (in contrib/) silently ignored
pathspec and other parameters.

* jk/jump-merge-with-pathspec:
  git-jump: pass "merge" arguments to ls-files

The code to decode the length of packed object size has been
corrected.

* jt/pack-header-lshift-overflow:
  packfile: avoid overflowing shift during decode

"diff --histogram" optimization.

* pw/xdiff-classify-record-in-histogram:
  xdiff: simplify comparison
  xdiff: avoid unnecessary memory allocations
  diff histogram: intern strings

trace2 error code path fix.

* js/trace2-avoid-recursive-errors:
  trace2: disable tr2_dst before warning on write errors

Test fix.

* jk/t5319-midx-corruption-test-deflake:
  t5319: corrupt more bytes of the midx checksum

Leakfix.

* ab/checkout-branch-info-leakfix:
  checkout: fix "branch info" memory leaks

…ge' into next

The advice message given by "git pull" when the user hasn't made a
choice between merge and rebase still said that the merge is the
default, which no longer is the case.  This has been corrected.

* ah/advice-pull-has-no-preference-between-rebase-and-merge:
  pull: don't say that merge is "the default strategy"

Bitop fix for platforms whose "long" is 32-bit.

* rs/mergesort:
  mergesort: avoid left shift overflow

* po/size-t-for-vs:
  object-file.c: LLP64 compatibility, upcast unity for left shift
  diffcore-delta.c: LLP64 compatibility, upcast unity for left shift
  repack.c: LLP64 compatibility, upcast unity for left shift

Doc mark-up fix.

* tl/midx-docfix:
  midx: fix a formatting issue in "multi-pack-index.txt"

Various operating modes of "git reset" have been made to work
better with the sparse index.

* vd/sparse-reset:
  unpack-trees: improve performance of next_cache_entry
  reset: make --mixed sparse-aware
  reset: make sparse-aware (except --mixed)
  reset: integrate with sparse index
  reset: expand test coverage for sparse checkouts
  sparse-index: update command for expand/collapse test
  reset: preserve skip-worktree bit in mixed reset
  reset: rename is_missing to !is_in_reset_tree

Comment fix.

* hk/ci-checkwhitespace-commentfix:
  ci(check-whitespace): update stale file top comments

"git fetch", when received a bad packfile, can fail with SIGPIPE.
This wasn't wrong per-se, but we now detect the situation and fail
in a more predictable way.

* jk/fetch-pack-avoid-sigpipe-to-index-pack:
  fetch-pack: ignore SIGPIPE when writing to index-pack

Workaround for a false-alarm by gcc-11

* jk/refs-g11-workaround:
  refs: work around gcc-11 warning with REF_HAVE_NEW

The function to cull a child process and determine the exit status
had two separate code paths for normal callers and callers in a
signal handler, and the latter did not yield correct value when the
child has caught a signal.  The handling of the exit status has
been unified for these two code paths.  An existing test with
flakiness has also been corrected.

* jk/t7006-sigpipe-tests-fix:
  t7006: simplify exit-code checks for sigpipe tests
  t7006: clean up SIGPIPE handling in trace2 tests
  run-command: unify signal and regular logic for wait_or_whine()

Docfix.

* jt/midx-doc-fix:
  Doc: no midx and partial clone relation

A small simplification of API.

* hn/create-reflog-simplify:
  refs: drop force_create argument of create_reflog API

Weather balloon to break people with compilers that do not support
C99.

* bc/require-c99:
  git-compat-util: add a test balloon for C99 support

The "reftable" backend for the refs API, without integrating into
the refs subsystem, has been added.

* hn/reftable:
  Add "test-tool dump-reftable" command.
  reftable: add dump utility
  reftable: implement stack, a mutable database of reftable files.
  reftable: implement refname validation
  reftable: add merged table view
  reftable: add a heap-based priority queue for reftable records
  reftable: reftable file level tests
  reftable: read reftable files
  reftable: generic interface to tables
  reftable: write reftable files
  reftable: a generic binary tree implementation
  reftable: reading/writing blocks
  Provide zlib's uncompress2 from compat/zlib-compat.c
  reftable: (de)serialization for the polymorphic record type.
  reftable: add blocksource, an abstraction for random access reads
  reftable: utility functions
  reftable: add error related functionality
  reftable: add LICENSE
  hash.h: provide constants for the hash IDs

The RCS keyword substitution in "git p4" used to be done assuming
that the contents are UTF-8 text, which can trigger decoding
errors.  We now treat the contents as a bytestring for robustness
and correctness.

* jh/p4-rcs-expansion-in-bytestring:
  git-p4: resolve RCS keywords in bytes not utf-8
  git-p4: open temporary patch file for write only
  git-p4: add raw option to read_pipelines
  git-p4: pre-compile RCS keyword regexes
  git-p4: use with statements to close files after use in patchRCSKeywords

The conditions to choose different definitions of the FLEX_ARRAY
macro for vendor compilers has been simplified to make it easier to
maintain.

* jc/flex-array-definition:
  flex-array: simplify compiler-specific workaround

Many git commands that deal with working tree files try to remove a
directory that becomes empty (i.e. "git switch" from a branch that
has the directory to another branch that does not would attempt
remove all files in the directory and the directory itself).  This
drops users into an unfamiliar situation if the command was run in
a subdirectory that becomes subject to removal due to the command.
The commands have been taught to keep an empty directory if it is
the directory they were started in to avoid surprising users.

* en/keep-cwd:
  t2501: simplify the tests since we can now assume desired behavior
  dir: new flag to remove_dir_recurse() to spare the original_cwd
  dir: avoid incidentally removing the original_cwd in remove_path()
  stash: do not attempt to remove startup_info->original_cwd
  rebase: do not attempt to remove startup_info->original_cwd
  clean: do not attempt to remove startup_info->original_cwd
  symlinks: do not include startup_info->original_cwd in dir removal
  unpack-trees: add special cwd handling
  unpack-trees: refuse to remove startup_info->original_cwd
  setup: introduce startup_info->original_cwd
  t2501: add various tests for removing the current working directory

"git am" learns "--empty=(stop|drop|keep)" option to tweak what is
done to a piece of e-mail without a patch in it.

* xw/am-empty:
  am: support --allow-empty to record specific empty patches
  am: support --empty=<option> to handle empty patches
  doc: git-format-patch: describe the option --always

Correctness and performance update to "diff --color-moved" feature.

* pw/diff-color-moved-fix:
  diff --color-moved: intern strings
  diff: use designated initializers for emitted_diff_symbol
  diff --color-moved-ws=allow-indentation-change: improve hash lookups
  diff --color-moved: stop clearing potential moved blocks
  diff --color-moved: shrink potential moved blocks as we go
  diff --color-moved: unify moved block growth functions
  diff --color-moved: call comparison function directly
  diff --color-moved-ws=allow-indentation-change: simplify and optimize
  diff: simplify allow-indentation-change delta calculation
  diff --color-moved: avoid false short line matches and bad zebra coloring
  diff --color-moved=zebra: fix alternate coloring
  diff --color-moved: rewind when discarding pmb
  diff --color-moved: factor out function
  diff --color-moved: clear all flags on blocks that are too short
  diff --color-moved: add perf tests

Docfix.

* jk/ssh-signing-doc-markup-fix:
  doc/config: mark ssh allowedSigners example as literal

"git upload-pack" (the other side of "git fetch") used a 8kB buffer
but most of its payload came on 64kB "packets".  The buffer size
has been enlarged so that such a packet fits.

* jv/use-larger-buffer-in-upload-pack:
  upload-pack.c: increase output buffer size

Among some code paths that ask an yes/no question, only one place
gave a prompt that looked different from the others, which has been
updated to match what the others create.

* km/help-prompt-fix:
  help: make auto-correction prompt more consistent

Certain sparse-checkout patterns that are valid in non-cone mode
led to segfault in cone mode, which has been corrected.

* ds/sparse-checkout-malformed-pattern-fix:
  fixup! sparse-checkout: fix OOM error with mixed patterns
  sparse-checkout: refuse to add to bad patterns
  sparse-checkout: fix OOM error with mixed patterns
  sparse-checkout: fix segfault on malformed patterns

The default merge message prepared by "git merge" records the name
of the current branch; the name can be overridden with a new option
to allow users to pretend a merge is made on a different branch.

* jc/merge-detached-head-name:
  merge: allow to pretend a merge is made into a different branch

Two fixes around "git repack".

* ds/repack-fixlets:
  repack: make '--quiet' disable progress
  repack: respect kept objects with '--write-midx -b'

Test fix.

* rs/t4202-invert-grep-test-fix:
  t4202: fix patternType setting in --invert-grep test

Doc markup fix.

* gh/gpg-doc-markup-fix:
  docs: add missing colon to Documentation/config/gpg.txt

"git log --invert-grep --author=<name>" used to exclude commits
written by the given author, but now "--invert-grep" only affects
the matches made by the "--grep=<pattern>" option.

* rs/log-invert-grep-with-headers:
  log: let --invert-grep only invert --grep

Test fixes.

* jc/t4204-do-not-write-git-on-upstream-of-pipe:
  t4204 is not sanitizer clean at all

"git grep --perl-regexp" failed to match UTF-8 characters with
wildcard when the pattern consists only of ASCII letters, which has
been corrected.

* rs/pcre2-utf:
  grep/pcre2: factor out literal variable
  grep/pcre2: use PCRE2_UTF even with ASCII patterns

Plug a memory leak.

* rs/daemon-plug-leak:
  daemon: plug memory leak on overlong path

This reverts commit d331468, which
will not be needed with the updated version of another topic that
the test was having trouble with.

* ds/sparse-checkout-malformed-pattern-fix:
  sparse-checkout: refuse to add to bad patterns
  sparse-checkout: fix OOM error with mixed patterns
  sparse-checkout: fix segfault on malformed patterns

Instead of comparing to the literal "HEAD", compare the commit objects
instead so that other ways of saying the same thing (such as "@") are
also handled appropriately.

Signed-off-by: "John Cai" <johncai86@gmail.com>