* sb/branch-avoid-repeated-strbuf-release:
  branch: reset instead of release a strbuf

* rs/qsort-s:
  test-stringlist: avoid buffer underrun when sorting nothing

* jn/strbuf-doc-re-reuse:
  strbuf doc: reuse after strbuf_release is fine

The feature that allows --pretty='%(trailers)' to take modifiers
like "fold" and "only" used to separate these modifiers with a
comma, i.e. "%(trailers:fold:only)", but we changed our mind and
use a comma, i.e. "%(trailers:fold,only)".  Fast track this change
before this new feature becomes part of any official release.

* tb/delimit-pretty-trailers-args-with-comma:
  pretty.c: delimit "%(trailers)" arguments with ","

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

Spell the name of our system as "Git" in the output from
request-pull script.

* ar/request-pull-phrasofix:
  request-pull: capitalise "Git" to make it a proper noun

Code clean-up.

* rs/run-command-use-alloc-array:
  run-command: use ALLOC_ARRAY

Add comment to clarify that the style file is meant to be used with
clang-5 and the rules are still work in progress.

* sb/git-clang-format:
  clang-format: add a comment about the meaning/status of the

Code clean-up.

* rs/use-free-and-null:
  repository: use FREE_AND_NULL

Code clean-up.

* rs/tag-null-pointer-arith-fix:
  tag: avoid NULL pointer arithmetic

Code clean-up.

* rs/cocci-de-paren-call-params:
  coccinelle: remove parentheses that become unnecessary

Code clean-up.

* rs/cleanup-strbuf-users:
  graph: use strbuf_addchars() to add spaces
  use strbuf_addstr() for adding strings to strbufs
  path: use strbuf_add_real_path()

Code clean-up.

* rs/resolve-ref-optional-result:
  refs: pass NULL to resolve_refdup() if hash is not needed
  refs: pass NULL to refs_resolve_refdup() if hash is not needed

The checkpoint command "git fast-import" did not flush updates to
refs and marks unless at least one object was created since the
last checkpoint, which has been corrected, as these things can
happen without any new object getting created.

* er/fast-import-dump-refs-on-checkpoint:
  fast-import: checkpoint: dump branches/tags/marks even if object_count==0

strbuf_release leaves the strbuf in a valid, initialized state, so
there is no need to call strbuf_init after it.

Moreover, this is not likely to change in the future: strbuf_release
leaving the strbuf in a valid state has been easy to maintain and has
been very helpful for Git's robustness and simplicity (e.g.,
preventing use-after-free vulnerabilities).

Document the semantics so the next generation of Git developers can
become familiar with them without reading the implementation.  It is
still not advisable to call strbuf_release too often because it is
wasteful, so add a note pointing to strbuf_reset for that.

The same semantics apply to strbuf_detach.  Add a similar note to its
docstring to make that clear.
Improved-by: NJeff King <peff@peff.net>
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Our documentation advises to not re-use a strbuf, after strbuf_release
has been called on it. Use the proper reset instead.

Currently 'strbuf_release' releases and re-initializes the strbuf, so it
is safe, but slow. 'strbuf_reset' only resets the internal length variable,
such that this could also be accounted for as a micro-optimization.
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Check if the strbuf containing data to sort is empty before attempting
to trim a trailing newline character.
Signed-off-by: NRene Scharfe <l.s.r@web.de>
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

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

Adjust clang-format penalty parameters.

* bw/git-clang-format:
  clang-format: adjust line break penalties

Docfix.

* ad/doc-markup-fix:
  doc: correct command formatting

Operations that do not touch (majority of) packed refs have been
optimized by making accesses to packed-refs file lazy; we no longer
pre-parse everything, and an access to a single ref in the
packed-refs does not touch majority of irrelevant refs, either.

* mh/mmap-packed-refs: (21 commits)
  packed-backend.c: rename a bunch of things and update comments
  mmapped_ref_iterator: inline into `packed_ref_iterator`
  ref_cache: remove support for storing peeled values
  packed_ref_store: get rid of the `ref_cache` entirely
  ref_store: implement `refs_peel_ref()` generically
  packed_read_raw_ref(): read the reference from the mmapped buffer
  packed_ref_iterator_begin(): iterate using `mmapped_ref_iterator`
  read_packed_refs(): ensure that references are ordered when read
  packed_ref_cache: keep the `packed-refs` file mmapped if possible
  packed-backend.c: reorder some definitions
  mmapped_ref_iterator_advance(): no peeled value for broken refs
  mmapped_ref_iterator: add iterator over a packed-refs file
  packed_ref_cache: remember the file-wide peeling state
  read_packed_refs(): read references with minimal copying
  read_packed_refs(): make parsing of the header line more robust
  read_packed_refs(): only check for a header at the top of the file
  read_packed_refs(): use mmap to read the `packed-refs` file
  die_unterminated_line(), die_invalid_line(): new functions
  packed_ref_cache: add a backlink to the associated `packed_ref_store`
  prefix_ref_iterator: break when we leave the prefix
  ...

Doc updates.

* mr/doc-negative-pathspec:
  docs: improve discoverability of exclude pathspec

Error message tweak.

* sb/submodule-diff-header-fix:
  submodule: correct error message for missing commits

The output from "git diff --summary" was broken in a recent topic
that has been merged to 'master' and lost a LF after reporting of
mode change.  This has been fixed.

* sb/diff-color-move:
  diff: correct newline in summary for renamed files

* sb/test-submodule-update-config:
  t7406: submodule.<name>.update command must not be run from .gitmodules

Code clean-up.

* jk/validate-headref-fix:
  validate_headref: use get_oid_hex for detached HEADs
  validate_headref: use skip_prefix for symref parsing
  validate_headref: NUL-terminate HEAD buffer

Code clean-up to prevent future mistakes by copying and pasting
code that checks the result of read_in_full() function.

* jk/read-in-full:
  worktree: check the result of read_in_full()
  worktree: use xsize_t to access file size
  distinguish error versus short read from read_in_full()
  avoid looking at errno for short read_in_full() returns
  prefer "!=" when checking read_in_full() result
  notes-merge: drop dead zero-write code
  files-backend: prefer "0" for write_in_full() error check

Some commands (most notably "git status") makes an opportunistic
update when performing a read-only operation to help optimize later
operations in the same repository.  The new "--no-optional-locks"
option can be passed to Git to disable them.

* jk/no-optional-locks:
  git: add --no-optional-locks option

Doc reorg.

* hn/string-list-doc:
  string-list.h: move documentation from Documentation/api/ into header

Add comment to a few functions that use a short-lived buffer the
caller can peek and copy out of.

* hn/path-ownership-comment:
  read_gitfile_gently: clarify return value ownership.
  real_path: clarify return value ownership

* hn/submodule-comment:
  submodule.c: describe submodule_to_gitdir() in a new comment

"git branch" learned "-c/-C" to create a new branch by copying an
existing one.

* sd/branch-copy:
  branch: fix "copy" to never touch HEAD
  branch: add a --copy (-c) option to go with --move (-m)
  branch: add test for -m renaming multiple config sections
  config: create a function to format section headers

Recent versions of "git rev-parse --parseopt" did not parse the
option specification that does not have the optional flags (*=?!)
correctly, which has been corrected.

* bc/rev-parse-parseopt-fix:
  parse-options: only insert newline in help text if needed
  parse-options: write blank line to correct output stream
  t0040,t1502: Demonstrate parse_options bugs
  git-rebase: don't ignore unexpected command line arguments
  rev-parse parseopt: interpret any whitespace as start of help text
  rev-parse parseopt: do not search help text for flag chars
  t1502: demonstrate rev-parse --parseopt option mis-parsing

The final batch to "git rebase -i" updates to move more code from
the shell script to C.

* js/rebase-i-final:
  rebase -i: rearrange fixup/squash lines using the rebase--helper
  t3415: test fixup with wrapped oneline
  rebase -i: skip unnecessary picks using the rebase--helper
  rebase -i: check for missing commits in the rebase--helper
  t3404: relax rebase.missingCommitsCheck tests
  rebase -i: also expand/collapse the SHA-1s via the rebase--helper
  rebase -i: do not invent onelines when expanding/collapsing SHA-1s
  rebase -i: remove useless indentation
  rebase -i: generate the script via rebase--helper
  t3415: verify that an empty instructionFormat is handled as before

Of the many ways to spell the three-letter word, the variant "Git"
should be used when referring to a repository in a description; or, in
general, when it is used as a proper noun.

We thus change the pull-request template message so that it reads

   "...in the Git repository at:"

Besides, this brings us in line with the documentation, see
Documentation/howto/using-signed-tag-in-pull-request.txt
Signed-off-by: NAnn T Ropea <bedhanger@gmx.de>
Acked-by: NJonathan Nieder <jrnieder@gmail.com>
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Use the macro ALLOC_ARRAY to allocate an array.  This is shorter and
easier, as it automatically infers the size of elements.

Patch generated with Coccinelle and contrib/coccinelle/array.cocci.
Signeg-off-by: NRene Scharfe <l.s.r@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Having a .clang-format file in a project can be understood in a way that
code has to be in the style defined by the .clang-format file, i.e., you
just have to run clang-format over all code and you are set.

This unfortunately is not yet the case in the Git project, as the
format file is still work in progress.  Explain it with a comment in
the beginning of the file.

Additionally, the working clang-format version is mentioned because the
config directives change from time to time (in a compatibility-breaking way).
Signed-off-by: NStephan Beyer <s-beyer@gmx.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Use the macro FREE_AND_NULL to release allocated objects and clear their
pointers.  This is shorter and documents the intent better by combining
the two related operations into one.

Patch generated with Coccinelle and contrib/coccinelle/free.cocci.
Signed-off-by: NRene Scharfe <l.s.r@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

lookup_blob() etc. can return NULL if the referenced object isn't of the
expected type.  In theory it's wrong to reference the object member in
that case.  In practice it's OK because it's located at offset 0 for all
types, so the pointer arithmetic (NULL + 0) is optimized out by the
compiler.  The issue is reported by Clang's AddressSanitizer, though.

Avoid the ASan error by casting the results of the lookup functions to
struct object pointers.  That works fine with NULL pointers as well.  We
already rely on the object member being first in all object types in
other places in the code.
Signed-off-by: NRene Scharfe <l.s.r@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

strbuf_addf() can be used to add a specific number of space characters
by using the format "%*s" with an empty string and specifying the
desired width.  Use strbuf_addchars() instead as it's shorter, makes the
intent clearer and is a bit more efficient.
Signed-off-by: NRene Scharfe <l.s.r@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>