Commit Graph

546 Commits

Author SHA1 Message Date
Junio C Hamano
a4bbd13be3 Merge branch 'hn/reftable'
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
2021-12-15 09:39:45 -08:00
Junio C Hamano
b8148376a2 Merge branch 'hn/create-reflog-simplify'
A small simplification of API.

* hn/create-reflog-simplify:
  refs: drop force_create argument of create_reflog API
2021-12-10 14:35:13 -08:00
Junio C Hamano
5396d7b298 Merge branch 'vd/sparse-sparsity-fix-on-read'
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
2021-12-10 14:35:01 -08:00
Junio C Hamano
f9ba6acaa9 Merge branch 'mc/clean-smudge-with-llp64'
The clean/smudge conversion code path has been prepared to better
work on platforms where ulong is narrower than size_t.

* mc/clean-smudge-with-llp64:
  clean/smudge: allow clean filters to process extremely large files
  odb: guard against data loss checking out a huge file
  git-compat-util: introduce more size_t helpers
  odb: teach read_blob_entry to use size_t
  t1051: introduce a smudge filter test for extremely large files
  test-lib: add prerequisite for 64-bit platforms
  test-tool genzeros: generate large amounts of data more efficiently
  test-genzeros: allow more than 2G zeros in Windows
2021-11-29 15:41:51 -08:00
Junio C Hamano
49767c3d9f Merge branch 'tb/plug-pack-bitmap-leaks'
Leakfix.

* tb/plug-pack-bitmap-leaks:
  pack-bitmap.c: more aggressively free in free_bitmap_index()
  pack-bitmap.c: don't leak type-level bitmaps
  midx.c: write MIDX filenames to strbuf
  builtin/multi-pack-index.c: don't leak concatenated options
  builtin/repack.c: avoid leaking child arguments
  builtin/pack-objects.c: don't leak memory via arguments
  t/helper/test-read-midx.c: free MIDX within read_midx_file()
  midx.c: don't leak MIDX from verify_midx_file
  midx.c: clean up chunkfile after reading the MIDX
2021-11-29 15:41:49 -08:00
Junio C Hamano
96f6623ada Merge branch 'ab/refs-errno-cleanup'
The "remainder" of hn/refs-errno-cleanup topic.

* ab/refs-errno-cleanup: (21 commits)
  refs API: post-migration API renaming [2/2]
  refs API: post-migration API renaming [1/2]
  refs API: don't expose "errno" in run_transaction_hook()
  refs API: make expand_ref() & repo_dwim_log() not set errno
  refs API: make resolve_ref_unsafe() not set errno
  refs API: make refs_ref_exists() not set errno
  refs API: make refs_resolve_refdup() not set errno
  refs tests: ignore ignore errno in test-ref-store helper
  refs API: ignore errno in worktree.c's find_shared_symref()
  refs API: ignore errno in worktree.c's add_head_info()
  refs API: make files_copy_or_rename_ref() et al not set errno
  refs API: make loose_fill_ref_dir() not set errno
  refs API: make resolve_gitlink_ref() not set errno
  refs API: remove refs_read_ref_full() wrapper
  refs/files: remove "name exist?" check in lock_ref_oid_basic()
  reflog tests: add --updateref tests
  refs API: make refs_rename_ref_available() static
  refs API: make parse_loose_ref_contents() not set errno
  refs API: make refs_read_raw_ref() not set errno
  refs API: add a version of refs_resolve_ref_unsafe() with "errno"
  ...
2021-11-29 15:41:45 -08:00
Victoria Dye
336d82e472 test-read-cache.c: prepare_repo_settings after config init
Move `prepare_repo_settings` after the git directory has been set up in
`test-read-cache.c`. The git directory settings must be initialized to
properly assign repo settings using the worktree-level git config.

Signed-off-by: Victoria Dye <vdye@github.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-24 16:32:38 -08:00
Han-Wen Nienhuys
7b089120d9 refs: drop force_create argument of create_reflog API
There is only one caller, builtin/checkout.c, and it hardcodes
force_create=1.

This argument was introduced in abd0cd3a30 (refs: new public ref function:
safe_create_reflog, 2015-07-21), which promised to immediately use it in a
follow-on commit, but that never happened.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-22 11:01:25 -08:00
Johannes Schindelin
df7000cd91 test-tool genzeros: generate large amounts of data more efficiently
In this developer's tests, producing one gigabyte worth of NULs in a
busy loop that writes out individual bytes, unbuffered, took ~27sec.
Writing chunked 256kB buffers instead only took ~0.6sec

This matters because we are about to introduce a pair of test cases that
want to be able to produce 5GB of NULs, and we cannot use `/dev/zero`
because of the HP NonStop platform's lack of support for that device.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-03 11:22:26 -07:00
Carlo Marcelo Arenas Belón
cbc985a1f4 test-genzeros: allow more than 2G zeros in Windows
d5cfd142ec (tests: teach the test-tool to generate NUL bytes and
use it, 2019-02-14), add a way to generate zeroes in a portable
way without using /dev/zero (needed by HP NonStop), but uses a
long variable that is limited to 2^31 in Windows.

Use instead a (POSIX/C99) intmax_t that is at least 64bit wide
in 64-bit Windows to use in a future test.

Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-03 11:22:26 -07:00
Taylor Blau
7f4c3508c0 t/helper/test-read-midx.c: free MIDX within read_midx_file()
When calling `read_midx_file()` to show information about a MIDX or list
the objects contained within it we fail to call `close_midx()`, leaking
the memory allocated to store that MIDX.

Fix this by calling `close_midx()` before exiting the function. We can
drop the "early" return when `show_objects` is non-zero, since the next
instruction is also a return.

(We could just as easily put a `cleanup` label here as with previous
patches. But the only other time we terminate the function early is
when we fail to load a MIDX in the first place. `close_midx()` does
handle a NULL argument, but the extra complexity is likely not
warranted).

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-27 16:26:37 -07:00
Junio C Hamano
54c4f8ce52 Merge branch 'ab/mark-leak-free-tests-more'
Bunch of tests are marked as "passing leak check".

* ab/mark-leak-free-tests-more:
  merge: add missing strbuf_release()
  ls-files: add missing string_list_clear()
  ls-files: fix a trivial dir_clear() leak
  tests: fix test-oid-array leak, test in SANITIZE=leak
  tests: fix a memory leak in test-oidtree.c
  tests: fix a memory leak in test-parse-options.c
  tests: fix a memory leak in test-prio-queue.c
2021-10-25 16:06:59 -07:00
Junio C Hamano
0b69bb0fb1 Merge branch 'tb/repack-write-midx'
"git repack" has been taught to generate multi-pack reachability
bitmaps.

* tb/repack-write-midx:
  test-read-midx: fix leak of bitmap_index struct
  builtin/repack.c: pass `--refs-snapshot` when writing bitmaps
  builtin/repack.c: make largest pack preferred
  builtin/repack.c: support writing a MIDX while repacking
  builtin/repack.c: extract showing progress to a variable
  builtin/repack.c: rename variables that deal with non-kept packs
  builtin/repack.c: keep track of existing packs unconditionally
  midx: preliminary support for `--refs-snapshot`
  builtin/multi-pack-index.c: support `--stdin-packs` mode
  midx: expose `write_midx_file_only()` publicly
2021-10-18 15:47:57 -07:00
Junio C Hamano
0ef08090d2 Merge branch 'rs/mergesort'
The mergesort implementation used to sort linked list has been
optimized.

* rs/mergesort:
  test-mergesort: use repeatable random numbers
  mergesort: use ranks stack
  p0071: test performance of llist_mergesort()
  p0071: measure sorting of already sorted and reversed files
  test-mergesort: add unriffle_skewed mode
  test-mergesort: add unriffle mode
  test-mergesort: add generate subcommand
  test-mergesort: add test subcommand
  test-mergesort: add sort subcommand
  test-mergesort: use strbuf_getline()
2021-10-18 15:47:56 -07:00
Ævar Arnfjörð Bjarmason
f1da24ca5e refs API: post-migration API renaming [2/2]
Rename the transitory refs_werrres_ref_unsafe() function to
refs_resolve_ref_unsafe(), now that all callers of the old function
have learned to pass in a "failure_errno" parameter.

The coccinelle semantic patch added in the preceding commit works, but
I couldn't figure out how to get spatch(1) to re-flow these argument
lists (and sometimes make lines way too long), so this rename was done
with:

    perl -pi -e 's/refs_werrres_ref_unsafe/refs_resolve_ref_unsafe/g' \
    $(git grep -l refs_werrres_ref_unsafe -- '*.c')

But after that "make contrib/coccinelle/refs.cocci.patch" comes up
empty, so the result would have been the same. Let's remove that
transitory semantic patch file, we won't need to retain it for any
other in-flight changes, refs_werrres_ref_unsafe() only existed within
this patch series.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-16 11:17:04 -07:00
Ævar Arnfjörð Bjarmason
6846f7248d refs tests: ignore ignore errno in test-ref-store helper
The cmd_resolve_ref() function has always ignored errno on failure,
but let's do so explicitly when using the refs_resolve_ref_unsafe()
function.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-16 11:17:03 -07:00
Junio C Hamano
af303ee392 Merge branch 'jh/builtin-fsmonitor-part1'
Built-in fsmonitor (part 1).

* jh/builtin-fsmonitor-part1:
  t/helper/simple-ipc: convert test-simple-ipc to use start_bg_command
  run-command: create start_bg_command
  simple-ipc/ipc-win32: add Windows ACL to named pipe
  simple-ipc/ipc-win32: add trace2 debugging
  simple-ipc: move definition of ipc_active_state outside of ifdef
  simple-ipc: preparations for supporting binary messages.
  trace2: add trace2_child_ready() to report on background children
2021-10-13 15:15:58 -07:00
Junio C Hamano
404c4a5462 Merge branch 'ab/designated-initializers'
Code clean-up.

* ab/designated-initializers:
  cbtree.h: define cb_init() in terms of CBTREE_INIT
  *.h: move some *_INIT to designated initializers
  *.h _INIT macros: don't specify fields equal to 0
  *.[ch] *_INIT macros: use { 0 } for a "zero out" idiom
  submodule-config.h: remove unused SUBMODULE_INIT macro
2021-10-11 10:21:48 -07:00
Junio C Hamano
9567a670d2 Merge branch 'tb/midx-write-propagate-namehash'
"git multi-pack-index write --bitmap" learns to propagate the
hashcache from original bitmap to resulting bitmap.

* tb/midx-write-propagate-namehash:
  t5326: test propagating hashcache values
  p5326: generate pack bitmaps before writing the MIDX bitmap
  p5326: don't set core.multiPackIndex unnecessarily
  p5326: create missing 'perf-tag' tag
  midx.c: respect 'pack.writeBitmapHashcache' when writing bitmaps
  pack-bitmap.c: propagate namehash values from existing bitmaps
  t/helper/test-bitmap.c: add 'dump-hashes' mode
2021-10-11 10:21:46 -07:00
Han-Wen Nienhuys
d860c86ba5 Add "test-tool dump-reftable" command.
This command dumps individual tables or a stack of of tables.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 10:45:48 -07:00
Han-Wen Nienhuys
e48d427268 reftable: implement stack, a mutable database of reftable files.
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 10:45:48 -07:00
Han-Wen Nienhuys
acb533440f reftable: implement refname validation
The packed/loose format has restrictions on refnames: a and a/b cannot
coexist. This limitation does not apply to reftable per se, but must be
maintained for interoperability. This code adds validation routines to
abort transactions that are trying to add invalid names.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 10:45:48 -07:00
Han-Wen Nienhuys
1ae2b8cda8 reftable: add merged table view
This adds an abstract, read-only interface to the ref database.

This primitive is used to construct the read view of the ref database
(the read view is constructed by merging several *.ref files). It also
provides the mechanism to provide a unified view of the refs in the main
repository and the per-worktree refs.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 10:45:48 -07:00
Han-Wen Nienhuys
3b34f636df reftable: add a heap-based priority queue for reftable records
This is needed to create a merged view multiple reftables

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 10:45:48 -07:00
Han-Wen Nienhuys
ffc97f1a9e reftable: reftable file level tests
With support for reading and writing files in place, we can construct files (in
memory) and attempt to read them back.

Because some sections of the format are optional (eg. indices, log entries), we
have to exercise this code using multiple sizes of input data

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 10:45:48 -07:00
Han-Wen Nienhuys
35425d1034 reftable: a generic binary tree implementation
The reftable format includes support for an (OID => ref) map. This map can speed
up visibility and reachability checks. In particular, various operations along
the fetch/push path within Gerrit have ben sped up by using this structure.

The map is constructed with help of a binary tree. Object IDs are hashes, so
they are uniformly distributed. Hence, the tree does not attempt forced
rebalancing.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 10:45:48 -07:00
Han-Wen Nienhuys
e581fd7231 reftable: reading/writing blocks
The reftable format is structured as a sequence of block. Within a block,
records are prefix compressed, with an index of offsets for fully expand keys to
enable binary search within blocks.

This commit provides the logic to read and write these blocks.

Helped-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 10:45:48 -07:00
Han-Wen Nienhuys
e303bf22f9 reftable: (de)serialization for the polymorphic record type.
The reftable format is structured as a sequence of blocks, and each block
contains a sequence of prefix-compressed key-value records. There are 4 types of
records, and they have similarities in how they must be handled. This is
achieved by introducing a polymorphic 'record' type that encapsulates ref, log,
index and object records.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 10:45:48 -07:00
Han-Wen Nienhuys
ef8a6c6268 reftable: utility functions
This commit provides basic utility classes for the reftable library.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Helped-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 10:45:48 -07:00
René Scharfe
c90cfc225b test-mergesort: use repeatable random numbers
Use MINSTD to generate pseudo-random numbers consistently instead of
using rand(3), whose output can vary from system to system, and reset
its seed before filling in the test values.  This gives repeatable
results across versions and systems, which simplifies sharing and
comparing of results between developers.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 10:04:56 -07:00
Ævar Arnfjörð Bjarmason
6ad66ab45e tests: fix test-oid-array leak, test in SANITIZE=leak
Fix a trivial memory leak present ever since 38d905bf58 (sha1-array:
add test-sha1-array and basic tests, 2014-10-01), now that that's
fixed we can test this under GIT_TEST_PASSING_SANITIZE_LEAK=true.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-07 15:40:15 -07:00
Ævar Arnfjörð Bjarmason
926d233035 tests: fix a memory leak in test-oidtree.c
Fix a memory leak in t/helper/test-oidtree.c, we were not freeing the
"struct strbuf" we used for the stdin input we parsed. This leak has
been here ever since 92d8ed8ac1 (oidtree: a crit-bit tree for
odb_loose_cache, 2021-07-07).

Now that it's fixed we can declare that t0069-oidtree.sh will pass
under GIT_TEST_PASSING_SANITIZE_LEAK=true.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-07 15:40:15 -07:00
Ævar Arnfjörð Bjarmason
c0b80e05f7 tests: fix a memory leak in test-parse-options.c
Fix a memory leak in t/helper/test-parse-options.c, we were not
freeing the allocated "struct string_list" or its items. Let's move
the declaration of the "list" variable into the cmd__parse_options()
and release it at the end.

In c8ba163916 (parse-options: add OPT_STRING_LIST helper, 2011-06-09)
the "list" variable was added, and later on in
c8ba163916 (parse-options: add OPT_STRING_LIST helper, 2011-06-09)
the "expect" was added.

The "list" variable was last touched in 2721ce21e4 (use string_list
initializer consistently, 2016-06-13), but it was still left at the
static scope, it's better to move it to the function for consistency.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-07 15:40:15 -07:00
Ævar Arnfjörð Bjarmason
6a75658c0a tests: fix a memory leak in test-prio-queue.c
Fix a memory leak in t/helper/test-prio-queue.c, the lack of freeing
the memory with clear_prio_queue() has been there ever since this code
was originally added in b4b594a315 (prio-queue: priority queue of
pointers to structs, 2013-06-06).

By fixing this leak we can cleanly run t0009-prio-queue.sh under
SANITIZE=leak, so annotate it as such with
TEST_PASSES_SANITIZE_LEAK=true.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-07 15:40:15 -07:00
Jeff King
e861b09636 test-read-midx: fix leak of bitmap_index struct
In read_midx_preferred_pack(), we open the bitmap index but never free
it. This isn't a big deal since this is just a test helper, and we exit
immediately after, but since we're trying to keep our leak-checking tidy
now, it's worth fixing.

Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-07 11:01:22 -07:00
Junio C Hamano
d8d33378ed Merge branch 'ab/repo-settings-cleanup'
Code cleanup.

* ab/repo-settings-cleanup:
  repository.h: don't use a mix of int and bitfields
  repo-settings.c: simplify the setup
  read-cache & fetch-negotiator: check "enum" values in switch()
  environment.c: remove test-specific "ignore_untracked..." variable
  wrapper.c: add x{un,}setenv(), and use xsetenv() in environment.c
2021-10-06 13:40:11 -07:00
Junio C Hamano
921c795c25 Merge branch 'jt/add-submodule-odb-clean-up'
More code paths that use the hack to add submodule's object
database to the set of alternate object store have been cleaned up.

* jt/add-submodule-odb-clean-up:
  revision: remove "submodule" from opt struct
  repository: support unabsorbed in repo_submodule_init
  submodule: remove unnecessary unabsorbed fallback
2021-10-06 13:40:11 -07:00
René Scharfe
f1ed4ce9e3 test-mergesort: add unriffle_skewed mode
Add a mode that turns a sorted list into adversarial input for a
bottom-up mergesort implementation that doubles the length of sorted
sublists at each level -- like our llist_mergesort().

While unriffle mode splits the list in half at each recursion step,
unriffle_skewed splits it into 2^l items and the rest, with 2^l being
the highest power of two smaller than the number of items and thus
2^l >= rest.  The rest is unriffled with the tail of the first half to
require a merge to compare the maximum number of elements.

It complements the unriffle mode, which targets balanced merges.  If
the number of elements is a power of two then both actually produce the
same result, as 2^l == rest == n/2 at each recursion step in that case.

Here are the results:

   $ t/helper/test-tool mergesort test | awk '
      $7 > max[$3] {max[$3] = $7; line[$3] = $0}
      END {for (n in line) print line[n]}
   '

distribut mode                    n        m get_next set_next  compare verdict
sawtooth  unriffle_skewed       100      128     1184      700      589 OK
sawtooth  unriffle_skewed      1023     1024    16373    10230     9207 OK
sawtooth  unriffle             1024     1024    16384    10240     9217 OK
sawtooth  unriffle_skewed      1025     2048    18454    11275    10241 OK

The sawtooth distribution with m>=n produces a sorted list and
unriffle_skewed mode turns it into adversarial input for unbalanced
merges, which it wins in all cases except for n=1024 -- the resulting
list is the same, but unriffle is tested before unriffle_skewed, so its
result is selected by the AWK script.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-01 12:43:09 -07:00
René Scharfe
1aa589922b test-mergesort: add unriffle mode
Add a mode that turns sorted items into adversarial input for mergesort.
Do that by running mergesort in reverse and rearranging the items in
such a way that each merge needs the maximum number of operations to
undo it.

To riffle is a card shuffling technique and involves splitting a deck
into two and then to interleave them.  A perfect riffle takes one card
from each half in turn.  That's similar to the most expensive merge,
which has to take one item from each sublist in turn, which requires the
maximum number of comparisons (n-1).

So unriffle does that in reverse, i.e. it generates the first sublist
out of the items at even indexes and the second sublist out of the items
at odd indexes, without changing their order in any other way.  Done
recursively until we reach the trivial sublist length of one, this
twists the list into an order that requires the maximum effort for
mergesort to untangle.

As a baseline, here are the rand distributions with the highest number
of comparisons from "test-tool mergesort test":

   $ t/helper/test-tool mergesort test | awk '
      NR > 1 && $1 != "rand" {next}
      $7 > max[$3] {max[$3] = $7; line[$3] = $0}
      END {for (n in line) print line[n]}
   '

distribut mode                    n        m get_next set_next  compare verdict
rand      copy                  100       32     1184      700      569 OK
rand      reverse_1st_half     1023      256    16373    10230     8976 OK
rand      reverse_1st_half     1024      512    16384    10240     8993 OK
rand      dither               1025       64    18454    11275     9970 OK

And here are the most expensive ones overall:

   $ t/helper/test-tool mergesort test | awk '
      $7 > max[$3] {max[$3] = $7; line[$3] = $0}
      END {for (n in line) print line[n]}
   '

distribut mode                    n        m get_next set_next  compare verdict
stagger   reverse               100       64     1184      700      580 OK
sawtooth  unriffle             1023     1024    16373    10230     9179 OK
sawtooth  unriffle             1024     1024    16384    10240     9217 OK
stagger   unriffle             1025     2048    18454    11275    10241 OK

The sawtooth distribution with m>=n generates a sorted list.  The
unriffle mode is designed to turn that into adversarial input for
mergesort, and that checks out for n=1023 and n=1024, where it produces
the list that requires the most comparisons.

Item counts that are not powers of two have other winners, and that's
because unriffle recursively splits lists into equal-sized halves, while
llist_mergesort() splits them into the biggest power of two smaller than
n and the rest, e.g. for n=1025 it sorts the first 1024 separately and
finally merges them to the last item.

So unriffle mode works as designed for the intended use case, but to
consistently generate adversarial input for unbalanced merges we need
something else.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-01 12:43:08 -07:00
René Scharfe
0cecb75531 test-mergesort: add generate subcommand
Add a subcommand for printing test data.  It can be used to generate
special test cases and feed them into the sort subcommand or sort(1) for
performance measurements.  It may also be useful to illustrate the
effect of distributions, modes and their parameters.

It generates n integers with the specified distribution and its
distribution-specific parameter m.  E.g. m is the maximum value for
the plateau distribution and the length and height of individual teeth
of the sawtooth distribution.

The generated values are printed as zero-padded eight-digit hexadecimal
numbers to make sure alphabetic and numeric order are the same.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-01 12:43:08 -07:00
René Scharfe
e031e9719d test-mergesort: add test subcommand
Adapt the qsort certification program from "Engineering a Sort Function"
by Bentley and McIlroy for testing our linked list sort function.  It
generates several lists with various distribution patterns and counts
the number of operations llist_mergesort() needs to order them.  It
compares the result to the output of a trusted sort function (qsort(1))
and also checks if the sort is stable.

Also add a test script that makes use of the new subcommand.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-01 12:43:08 -07:00
René Scharfe
d536a71169 test-mergesort: add sort subcommand
Give the code for sorting a text file its own sub-command.  This allows
extending the helper, which we'll do in the following patches.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-01 12:43:08 -07:00
René Scharfe
2e6701017e test-mergesort: use strbuf_getline()
Strip line ending characters to make sure empty lines are sorted like
sort(1) does.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-01 12:43:08 -07:00
Taylor Blau
6d08b9d4ca builtin/repack.c: make largest pack preferred
When repacking into a geometric series and writing a multi-pack bitmap,
it is beneficial to have the largest resulting pack be the preferred
object source in the bitmap's MIDX, since selecting the large packs can
lead to fewer broken delta chains and better compression.

Teach 'git repack' to identify this pack and pass it to the MIDX write
machinery in order to mark it as preferred.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-28 21:20:56 -07:00
Ævar Arnfjörð Bjarmason
f69a6e4f07 *.h: move some *_INIT to designated initializers
Move various *_INIT macros to use designated initializers. This helps
readability. I've only picked those leftover macros that were not
touched by another in-flight series of mine which changed others, but
also how initialization was done.

In the case of SUBMODULE_ALTERNATE_SETUP_INIT I've left an explicit
initialization of "error_mode", even though
SUBMODULE_ALTERNATE_ERROR_IGNORE itself is defined as "0". Let's not
peek under the hood and assume that enum fields we know the value of
will stay at "0".

The change to "TESTSUITE_INIT" in "t/helper/test-run-command.c" was
part of an earlier on-list version[1] of c90be786da (test-tool
run-command: fix flip-flop init pattern, 2021-09-11).

1. https://lore.kernel.org/git/patch-1.1-0aa4523ab6e-20210909T130849Z-avarab@gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 14:48:00 -07:00
Ævar Arnfjörð Bjarmason
608cfd31cf *.h _INIT macros: don't specify fields equal to 0
Change the initialization of "struct strbuf" changed in
cbc0f81d96 (strbuf: use designated initializers in STRBUF_INIT,
2017-07-10) to omit specifying "alloc" and "len", as we do with other
"alloc" and "len" (or "nr") in similar structs.

Let's likewise omit the explicit initialization of all fields in the
"struct ipc_client_connect_option" struct added in
59c7b88198 (simple-ipc: add win32 implementation, 2021-03-15).

Do the same for a few other initializers, e.g. STRVEC_INIT and
CACHE_DEF_INIT.

Finally, start incrementally changing the same pattern in
"t/helper/test-run-command.c". This change was part of an earlier
on-list version[1] of c90be786da (test-tool run-command: fix
flip-flop init pattern, 2021-09-11).

1. https://lore.kernel.org/git/patch-1.1-0aa4523ab6e-20210909T130849Z-avarab@gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-27 14:47:59 -07:00
Junio C Hamano
0e35107e7d Merge branch 'ab/retire-option-argument'
An oddball OPTION_ARGUMENT feature has been removed from the
parse-options API.

* ab/retire-option-argument:
  parse-options API: remove OPTION_ARGUMENT feature
  difftool: use run_command() API in run_file_diff()
  difftool: prepare "diff" cmdline in cmd_difftool()
  difftool: prepare "struct child_process" in cmd_difftool()
2021-09-23 13:44:48 -07:00
Junio C Hamano
ffb0387608 Merge branch 'ab/test-tool-run-command-cleanup'
Code clean-up.

* ab/test-tool-run-command-cleanup:
  test-tool run-command: fix flip-flop init pattern
2021-09-23 13:44:46 -07:00
Ævar Arnfjörð Bjarmason
c6b4888b3f environment.c: remove test-specific "ignore_untracked..." variable
Instead of the global ignore_untracked_cache_config variable added in
dae6c322fa (test-dump-untracked-cache: don't modify the untracked
cache, 2016-01-27) we can make use of the new facility to set config
via environment variables added in d8d77153ea (config: allow
specifying config entries via envvar pairs, 2021-01-12).

It's arguably a bit hacky to use setenv() and getenv() to pass
messages between the same program, but since the test helpers are not
the main intended audience of repo-settings.c I think it's better than
hardcoding the test-only special-case in prepare_repo_settings().

This uses the xsetenv() wrapper added in the preceding commit, if we
don't set these in the environment we'll fail in
t7063-status-untracked-cache.sh, but let's fail earlier anyway if that
were to happen.

This breaks any parent process that's potentially using the
GIT_CONFIG_* and GIT_CONFIG_PARAMETERS mechanism to pass one-shot
config setting down to a git subprocess, but in this case we don't
care about the general case of such potential parents. This process
neither spawns other "git" processes, nor is it interested in other
configuration. We might want to pick up other test modes here, but
those will be passed via GIT_TEST_* environment variables.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-22 13:15:00 -07:00
Junio C Hamano
5331af2352 Merge branch 'ab/serve-cleanup'
Code clean-up around "git serve".

* ab/serve-cleanup:
  upload-pack: document and rename --advertise-refs
  serve.[ch]: remove "serve_options", split up --advertise-refs code
  {upload,receive}-pack tests: add --advertise-refs tests
  serve.c: move version line to advertise_capabilities()
  serve: move transfer.advertiseSID check into session_id_advertise()
  serve.[ch]: don't pass "struct strvec *keys" to commands
  serve: use designated initializers
  transport: use designated initializers
  transport: rename "fetch" in transport_vtable to "fetch_refs"
  serve: mark has_capability() as static
2021-09-20 15:20:43 -07:00