Commit Graph

115389 Commits

Author SHA1 Message Date
Derrick Stolee
4950b2a2b5 for-each-repo: run subcommands on configured repos
It can be helpful to store a list of repositories in global or system
config and then iterate Git commands on that list. Create a new builtin
that makes this process simple for experts. We will use this builtin to
run scheduled maintenance on all configured repositories in a future
change.

The test is very simple, but does highlight that the "--" argument is
optional.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 10:59:44 -07:00
Derrick Stolee
b08ff1fee0 maintenance: add --schedule option and config
Maintenance currently triggers when certain data-size thresholds are
met, such as number of pack-files or loose objects. Users may want to
run certain maintenance tasks based on frequency instead. For example,
a user may want to perform a 'prefetch' task every hour, or 'gc' task
every day. To help these users, update the 'git maintenance run' command
to include a '--schedule=<frequency>' option. The allowed frequencies
are 'hourly', 'daily', and 'weekly'. These values are also allowed in a
new config value 'maintenance.<task>.schedule'.

The 'git maintenance run --schedule=<frequency>' checks the '*.schedule'
config value for each enabled task to see if the configured frequency is
at least as frequent as the frequency from the '--schedule' argument. We
use the following order, for full clarity:

	'hourly' > 'daily' > 'weekly'

Use new 'enum schedule_priority' to track these values numerically.

The following cron table would run the scheduled tasks with the correct
frequencies:

  0 1-23 * * *    git -C <repo> maintenance run --schedule=hourly
  0 0    * * 1-6  git -C <repo> maintenance run --schedule=daily
  0 0    * * 0    git -C <repo> maintenance run --schedule=weekly

This cron schedule will run --schedule=hourly every hour except at
midnight. This avoids a concurrent run with the --schedule=daily that
runs at midnight every day except the first day of the week. This avoids
a concurrent run with the --schedule=weekly that runs at midnight on
the first day of the week. Since --schedule=daily also runs the
'hourly' tasks and --schedule=weekly runs the 'hourly' and 'daily'
tasks, we will still see all tasks run with the proper frequencies.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 10:59:44 -07:00
Derrick Stolee
1942d48380 maintenance: optionally skip --auto process
Some commands run 'git maintenance run --auto --[no-]quiet' after doing
their normal work, as a way to keep repositories clean as they are used.
Currently, users who do not want this maintenance to occur would set the
'gc.auto' config option to 0 to avoid the 'gc' task from running.
However, this does not stop the extra process invocation. On Windows,
this extra process invocation can be more expensive than necessary.

Allow users to drop this extra process by setting 'maintenance.auto' to
'false'.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 10:59:44 -07:00
Derrick Stolee
e841a79a13 maintenance: add incremental-repack auto condition
The incremental-repack task updates the multi-pack-index by deleting pack-
files that have been replaced with new packs, then repacking a batch of
small pack-files into a larger pack-file. This incremental repack is faster
than rewriting all object data, but is slower than some other
maintenance activities.

The 'maintenance.incremental-repack.auto' config option specifies how many
pack-files should exist outside of the multi-pack-index before running
the step. These pack-files could be created by 'git fetch' commands or
by the loose-objects task. The default value is 10.

Setting the option to zero disables the task with the '--auto' option,
and a negative value makes the task run every time.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 10:53:05 -07:00
Derrick Stolee
a13e3d0ec8 maintenance: auto-size incremental-repack batch
When repacking during the 'incremental-repack' task, we use the
--batch-size option in 'git multi-pack-index repack'. The initial setting
used --batch-size=0 to repack everything into a single pack-file. This is
not sustainable for a large repository. The amount of work required is
also likely to use too many system resources for a background job.

Update the 'incremental-repack' task by dynamically computing a
--batch-size option based on the current pack-file structure.

The dynamic default size is computed with this idea in mind for a client
repository that was cloned from a very large remote: there is likely one
"big" pack-file that was created at clone time. Thus, do not try
repacking it as it is likely packed efficiently by the server.

Instead, we select the second-largest pack-file, and create a batch size
that is one larger than that pack-file. If there are three or more
pack-files, then this guarantees that at least two will be combined into
a new pack-file.

Of course, this means that the second-largest pack-file size is likely
to grow over time and may eventually surpass the initially-cloned
pack-file. Recall that the pack-file batch is selected in a greedy
manner: the packs are considered from oldest to newest and are selected
if they have size smaller than the batch size until the total selected
size is larger than the batch size. Thus, that oldest "clone" pack will
be first to repack after the new data creates a pack larger than that.

We also want to place some limits on how large these pack-files become,
in order to bound the amount of time spent repacking. A maximum
batch-size of two gigabytes means that large repositories will never be
packed into a single pack-file using this job, but also that repack is
rather expensive. This is a trade-off that is valuable to have if the
maintenance is being run automatically or in the background. Users who
truly want to optimize for space and performance (and are willing to pay
the upfront cost of a full repack) can use the 'gc' task to do so.

Create a test for this two gigabyte limit by creating an EXPENSIVE test
that generates two pack-files of roughly 2.5 gigabytes in size, then
performs an incremental repack. Check that the --batch-size argument in
the subcommand uses the hard-coded maximum.

Helped-by: Chris Torek <chris.torek@gmail.com>
Reported-by: Son Luong Ngoc <sluongng@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 10:53:05 -07:00
Derrick Stolee
52fe41ff1c maintenance: add incremental-repack task
The previous change cleaned up loose objects using the
'loose-objects' that can be run safely in the background. Add a
similar job that performs similar cleanups for pack-files.

One issue with running 'git repack' is that it is designed to
repack all pack-files into a single pack-file. While this is the
most space-efficient way to store object data, it is not time or
memory efficient. This becomes extremely important if the repo is
so large that a user struggles to store two copies of the pack on
their disk.

Instead, perform an "incremental" repack by collecting a few small
pack-files into a new pack-file. The multi-pack-index facilitates
this process ever since 'git multi-pack-index expire' was added in
19575c7 (multi-pack-index: implement 'expire' subcommand,
2019-06-10) and 'git multi-pack-index repack' was added in ce1e4a1
(midx: implement midx_repack(), 2019-06-10).

The 'incremental-repack' task runs the following steps:

1. 'git multi-pack-index write' creates a multi-pack-index file if
   one did not exist, and otherwise will update the multi-pack-index
   with any new pack-files that appeared since the last write. This
   is particularly relevant with the background fetch job.

   When the multi-pack-index sees two copies of the same object, it
   stores the offset data into the newer pack-file. This means that
   some old pack-files could become "unreferenced" which I will use
   to mean "a pack-file that is in the pack-file list of the
   multi-pack-index but none of the objects in the multi-pack-index
   reference a location inside that pack-file."

2. 'git multi-pack-index expire' deletes any unreferenced pack-files
   and updaes the multi-pack-index to drop those pack-files from the
   list. This is safe to do as concurrent Git processes will see the
   multi-pack-index and not open those packs when looking for object
   contents. (Similar to the 'loose-objects' job, there are some Git
   commands that open pack-files regardless of the multi-pack-index,
   but they are rarely used. Further, a user that self-selects to
   use background operations would likely refrain from using those
   commands.)

3. 'git multi-pack-index repack --bacth-size=<size>' collects a set
   of pack-files that are listed in the multi-pack-index and creates
   a new pack-file containing the objects whose offsets are listed
   by the multi-pack-index to be in those objects. The set of pack-
   files is selected greedily by sorting the pack-files by modified
   time and adding a pack-file to the set if its "expected size" is
   smaller than the batch size until the total expected size of the
   selected pack-files is at least the batch size. The "expected
   size" is calculated by taking the size of the pack-file divided
   by the number of objects in the pack-file and multiplied by the
   number of objects from the multi-pack-index with offset in that
   pack-file. The expected size approximates how much data from that
   pack-file will contribute to the resulting pack-file size. The
   intention is that the resulting pack-file will be close in size
   to the provided batch size.

   The next run of the incremental-repack task will delete these
   repacked pack-files during the 'expire' step.

   In this version, the batch size is set to "0" which ignores the
   size restrictions when selecting the pack-files. It instead
   selects all pack-files and repacks all packed objects into a
   single pack-file. This will be updated in the next change, but
   it requires doing some calculations that are better isolated to
   a separate change.

These steps are based on a similar background maintenance step in
Scalar (and VFS for Git) [1]. This was incredibly effective for
users of the Windows OS repository. After using the same VFS for Git
repository for over a year, some users had _thousands_ of pack-files
that combined to up to 250 GB of data. We noticed a few users were
running into the open file descriptor limits (due in part to a bug
in the multi-pack-index fixed by af96fe3 (midx: add packs to
packed_git linked list, 2019-04-29).

These pack-files were mostly small since they contained the commits
and trees that were pushed to the origin in a given hour. The GVFS
protocol includes a "prefetch" step that asks for pre-computed pack-
files containing commits and trees by timestamp. These pack-files
were grouped into "daily" pack-files once a day for up to 30 days.
If a user did not request prefetch packs for over 30 days, then they
would get the entire history of commits and trees in a new, large
pack-file. This led to a large number of pack-files that had poor
delta compression.

By running this pack-file maintenance step once per day, these repos
with thousands of packs spanning 200+ GB dropped to dozens of pack-
files spanning 30-50 GB. This was done all without removing objects
from the system and using a constant batch size of two gigabytes.
Once the work was done to reduce the pack-files to small sizes, the
batch size of two gigabytes means that not every run triggers a
repack operation, so the following run will not expire a pack-file.
This has kept these repos in a "clean" state.

[1] https://github.com/microsoft/scalar/blob/master/Scalar.Common/Maintenance/PackfileMaintenanceStep.cs

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 10:53:04 -07:00
Derrick Stolee
efdd2f0d4c midx: use start_delayed_progress()
Now that the multi-pack-index may be written as part of auto maintenance
at the end of a command, reduce the progress output when the operations
are quick. Use start_delayed_progress() instead of start_progress().

Update t5319-multi-pack-index.sh to use GIT_PROGRESS_DELAY=0 now that
the progress indicators are conditional.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 10:53:04 -07:00
Derrick Stolee
18e449f86b midx: enable core.multiPackIndex by default
The core.multiPackIndex setting has been around since c4d25228eb
(config: create core.multiPackIndex setting, 2018-07-12), but has been
disabled by default. If a user wishes to use the multi-pack-index
feature, then they must enable this config and run 'git multi-pack-index
write'.

The multi-pack-index feature is relatively stable now, so make the
config option true by default. For users that do not use a
multi-pack-index, the only extra cost will be a file lookup to see if a
multi-pack-index file exists (once per process, per object directory).

Also, this config option will be referenced by an upcoming
"incremental-repack" task in the maintenance builtin, so move the config
option into the repository settings struct. Note that if
GIT_TEST_MULTI_PACK_INDEX=1, then we want to ignore the config option
and treat core.multiPackIndex as enabled.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 10:53:04 -07:00
Derrick Stolee
3e220e6069 maintenance: create auto condition for loose-objects
The loose-objects task deletes loose objects that already exist in a
pack-file, then place the remaining loose objects into a new pack-file.
If this step runs all the time, then we risk creating pack-files with
very few objects with every 'git commit' process. To prevent
overwhelming the packs directory with small pack-files, place a minimum
number of objects to justify the task.

The 'maintenance.loose-objects.auto' config option specifies a minimum
number of loose objects to justify the task to run under the '--auto'
option. This defaults to 100 loose objects. Setting the value to zero
will prevent the step from running under '--auto' while a negative value
will force it to run every time.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 10:53:04 -07:00
Derrick Stolee
252cfb7cb8 maintenance: add loose-objects task
One goal of background maintenance jobs is to allow a user to
disable auto-gc (gc.auto=0) but keep their repository in a clean
state. Without any cleanup, loose objects will clutter the object
database and slow operations. In addition, the loose objects will
take up extra space because they are not stored with deltas against
similar objects.

Create a 'loose-objects' task for the 'git maintenance run' command.
This helps clean up loose objects without disrupting concurrent Git
commands using the following sequence of events:

1. Run 'git prune-packed' to delete any loose objects that exist
   in a pack-file. Concurrent commands will prefer the packed
   version of the object to the loose version. (Of course, there
   are exceptions for commands that specifically care about the
   location of an object. These are rare for a user to run on
   purpose, and we hope a user that has selected background
   maintenance will not be trying to do foreground maintenance.)

2. Run 'git pack-objects' on a batch of loose objects. These
   objects are grouped by scanning the loose object directories in
   lexicographic order until listing all loose objects -or-
   reaching 50,000 objects. This is more than enough if the loose
   objects are created only by a user doing normal development.
   We noticed users with _millions_ of loose objects because VFS
   for Git downloads blobs on-demand when a file read operation
   requires populating a virtual file.

This step is based on a similar step in Scalar [1] and VFS for Git.
[1] https://github.com/microsoft/scalar/blob/master/Scalar.Common/Maintenance/LooseObjectsStep.cs

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 10:53:04 -07:00
Derrick Stolee
28cb5e66dd maintenance: add prefetch task
When working with very large repositories, an incremental 'git fetch'
command can download a large amount of data. If there are many other
users pushing to a common repo, then this data can rival the initial
pack-file size of a 'git clone' of a medium-size repo.

Users may want to keep the data on their local repos as close as
possible to the data on the remote repos by fetching periodically in
the background. This can break up a large daily fetch into several
smaller hourly fetches.

The task is called "prefetch" because it is work done in advance
of a foreground fetch to make that 'git fetch' command much faster.

However, if we simply ran 'git fetch <remote>' in the background,
then the user running a foreground 'git fetch <remote>' would lose
some important feedback when a new branch appears or an existing
branch updates. This is especially true if a remote branch is
force-updated and this isn't noticed by the user because it occurred
in the background. Further, the functionality of 'git push
--force-with-lease' becomes suspect.

When running 'git fetch <remote> <options>' in the background, use
the following options for careful updating:

1. --no-tags prevents getting a new tag when a user wants to see
   the new tags appear in their foreground fetches.

2. --refmap= removes the configured refspec which usually updates
   refs/remotes/<remote>/* with the refs advertised by the remote.
   While this looks confusing, this was documented and tested by
   b40a50264a (fetch: document and test --refmap="", 2020-01-21),
   including this sentence in the documentation:

	Providing an empty `<refspec>` to the `--refmap` option
	causes Git to ignore the configured refspecs and rely
	entirely on the refspecs supplied as command-line arguments.

3. By adding a new refspec "+refs/heads/*:refs/prefetch/<remote>/*"
   we can ensure that we actually load the new values somewhere in
   our refspace while not updating refs/heads or refs/remotes. By
   storing these refs here, the commit-graph job will update the
   commit-graph with the commits from these hidden refs.

4. --prune will delete the refs/prefetch/<remote> refs that no
   longer appear on the remote.

5. --no-write-fetch-head prevents updating FETCH_HEAD.

We've been using this step as a critical background job in Scalar
[1] (and VFS for Git). This solved a pain point that was showing up
in user reports: fetching was a pain! Users do not like waiting to
download the data that was created while they were away from their
machines. After implementing background fetch, the foreground fetch
commands sped up significantly because they mostly just update refs
and download a small amount of new data. The effect is especially
dramatic when paried with --no-show-forced-udpates (through
fetch.showForcedUpdates=false).

[1] https://github.com/microsoft/scalar/blob/master/Scalar.Common/Maintenance/FetchStep.cs

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 10:53:04 -07:00
Johannes Schindelin
3eccc7b99d cmake: ignore files generated by CMake as run in Visual Studio
As of recent Visual Studio versions, CMake support is built-in:
https://docs.microsoft.com/en-us/cpp/build/cmake-projects-in-visual-studio?view=vs-2019

All that needs to be done is to open the worktree as a folder, and
Visual Studio will find the `CMakeLists.txt` file and automatically
generate the project files.

Let's ignore the entirety of those generated files.

Helped-by: Đoàn Trần Công Danh <congdanhqx@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 10:50:44 -07:00
Jeff King
45d93eb824 shortlog: change "author" variables to "ident"
We already match "committer", and we're about to start
matching more things. Let's use a more neutral variable to
avoid confusion.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 10:47:50 -07:00
Christian Couder
73c6de06af bisect: don't use invalid oid as rev when starting
In 06f5608c14 (bisect--helper: `bisect_start` shell function
partially in C, 2019-01-02), we changed the following shell
code:

-      rev=$(git rev-parse -q --verify "$arg^{commit}") || {
-              test $has_double_dash -eq 1 &&
-              die "$(eval_gettext "'\$arg' does not appear to be a valid revision")"
-              break
-      }
-      revs="$revs $rev"

into:

+      char *commit_id = xstrfmt("%s^{commit}", arg);
+      if (get_oid(commit_id, &oid) && has_double_dash)
+              die(_("'%s' does not appear to be a valid "
+                    "revision"), arg);
+
+      string_list_append(&revs, oid_to_hex(&oid));
+      free(commit_id);

In case of an invalid "arg" when "has_double_dash" is false, the old
code would "break" out of the argument loop.

In the new C code though, `oid_to_hex(&oid)` is unconditonally
appended to "revs". This is wrong first because "oid" is junk as
`get_oid(commit_id, &oid)` failed and second because it doesn't break
out of the argument loop.

Not breaking out of the argument loop means that "arg" is then not
treated as a path restriction (which is wrong).

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 09:57:48 -07:00
Alex Henrie
54200cef86 pull: don't warn if pull.ff has been set
A user who understands enough to set pull.ff does not need additional
instructions.

Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-24 23:04:27 -07:00
Junio C Hamano
610e2b9240 blame: validate and peel the object names on the ignore list
The command reads list of object names to place on the ignore list
either from the command line or from a file, but they are not
checked with their object type (those read from the file are not
even checked for object existence).

Extend the oidset_parse_file() API and allow it to take a callback
that can be used to die (e.g. when an inappropriate input is read)
or modify the object name read (e.g. when a tag pointing at a commit
is read, and the caller wants a commit object name), and use it in
the code that handles ignore list.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-24 22:20:58 -07:00
Junio C Hamano
f58931c8d6 t8013: minimum preparatory clean-up
The closing sq for each test piece should be placed at the beginning
of line.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-24 22:20:57 -07:00
Johannes Schindelin
bcabfe850c squash! mingw: lstat: compute correct size for symlinks
Move this, and "fscache: compute correct symlink size in `lstat()`",
into "kblees/kb/symlinks".

Maybe even squash it into the appropriate commits, e.g. "mingw: teach
fscache and dirent about symlinks"?

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2020-09-24 21:56:10 +02:00
Thomas Guyot-Sionnest
ff0c7fa8cb diff: fix modified lines stats with --stat and --numstat
Only skip diffstats when both oids are valid and identical. This check
was causing both false-positives (files included in diffstats with no
actual changes (0 lines modified) and false-negatives (showing 0 lines
modified in stats when files had actually changed).

Also replaced same_contents with may_differ to avoid confusion.

Signed-off-by: Thomas Guyot-Sionnest <tguyot@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-24 12:31:45 -07:00
Jeff King
176380fd11 Revert "fast-export: use local array to store anonymized oid"
This reverts commit f39ad38410.

That commit was trying to silence a type-punning warning on older
versions of gcc. However, its analysis was all wrong. I didn't notice
that we _were_ in fact type-punning because there are two versions of
put_be32(): one that uses casts and unaligned loads, and another that
uses bitshifts. I looked at the latter, but on my platform we were
defaulting to the former.

However, as of the previous commit, we'll always use the bitshift
version. So we can drop this hackery to avoid the warning, making the
code slightly cleaner.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-24 12:30:11 -07:00
Jeff King
c578e29ba0 bswap.h: drop unaligned loads
Our put_be32() routine and its variants (get_be32(), put_be64(), etc)
has two implementations: on some platforms we cast memory in place and
use nothl()/htonl(), which can cause unaligned memory access. And on
others, we pick out the individual bytes using bitshifts.

This introduces extra complexity, and sometimes causes compilers to
generate warnings about type-punning. And it's not clear there's any
performance advantage.

This split goes back to 660231aa97 (block-sha1: support for
architectures with memory alignment restrictions, 2009-08-12). The
unaligned versions were part of the original block-sha1 code in
d7c208a92e (Add new optimized C 'block-sha1' routines, 2009-08-05),
which says it is:

   Based on the mozilla SHA1 routine, but doing the input data accesses a
   word at a time and with 'htonl()' instead of loading bytes and shifting.

Back then, Linus provided timings versus the mozilla code which showed a
27% improvement:

  https://lore.kernel.org/git/alpine.LFD.2.01.0908051545000.3390@localhost.localdomain/

However, the unaligned loads were either not the useful part of that
speedup, or perhaps compilers and processors have changed since then.
Here are times for computing the sha1 of 4GB of random data, with and
without -DNO_UNALIGNED_LOADS (and BLK_SHA1=1, of course). This is with
gcc 10, -O2, and the processor is a Core i9-9880H.

  [stock]
  Benchmark #1: t/helper/test-tool sha1 <foo.rand
    Time (mean ± σ):      6.638 s ±  0.081 s    [User: 6.269 s, System: 0.368 s]
    Range (min … max):    6.550 s …  6.841 s    10 runs

  [-DNO_UNALIGNED_LOADS]
  Benchmark #1: t/helper/test-tool sha1 <foo.rand
    Time (mean ± σ):      6.418 s ±  0.015 s    [User: 6.058 s, System: 0.360 s]
    Range (min … max):    6.394 s …  6.447 s    10 runs

And here's the same test run on an AMD A8-7600, using gcc 8.

  [stock]
  Benchmark #1: t/helper/test-tool sha1 <foo.rand
    Time (mean ± σ):     11.721 s ±  0.113 s    [User: 10.761 s, System: 0.951 s]
    Range (min … max):   11.509 s … 11.861 s    10 runs

  [-DNO_UNALIGNED_LOADS]
  Benchmark #1: t/helper/test-tool sha1 <foo.rand
    Time (mean ± σ):     11.744 s ±  0.066 s    [User: 10.807 s, System: 0.928 s]
    Range (min … max):   11.637 s … 11.863 s    10 runs

So the unaligned loads don't seem to help much, and actually make things
worse. It's possible there are platforms where they provide more
benefit, but:

  - the non-x86 platforms for which we use this code are old and obscure
    (powerpc and s390).

  - the main caller that cares about performance is block-sha1. But
    these days it is rarely used anyway, in favor of sha1dc (which is
    already much slower, and nobody seems to have cared that much).

Let's just drop unaligned versions entirely in the name of simplicity.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-24 12:30:09 -07:00
Pranit Bauva
517ecb3161 bisect--helper: reimplement bisect_next and bisect_auto_next shell functions in C
Reimplement the `bisect_next()` and the `bisect_auto_next()` shell functions
in C and add the subcommands to `git bisect--helper` to call them from
git-bisect.sh .

bisect_auto_next() function returns an enum bisect_error type as whole
`git bisect` can exit with an error code when bisect_next() does.

Return an error when `bisect_next()` fails, that fix a bug on shell script
version.

Using `--bisect-next` and `--bisect-auto-next` subcommands is a
temporary measure to port shell function to C so as to use the existing
test suite. As more functions are ported, `--bisect-auto-next`
subcommand will be retired and will be called by some other methods.

Mentored-by: Lars Schneider <larsxschneider@gmail.com>
Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Mentored-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Pranit Bauva <pranit.bauva@gmail.com>
Signed-off-by: Tanushree Tumane <tanushreetumane@gmail.com>
Signed-off-by: Miriam Rubio <mirucam@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-24 12:06:30 -07:00
Miriam Rubio
c7a7f48f4f bisect: call 'clear_commit_marks_all()' in 'bisect_next_all()'
As there can be other revision walks after bisect_next_all(),
let's add a call to a function to clear all the marks at the
end of bisect_next_all().

Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Miriam Rubio <mirucam@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-24 12:06:30 -07:00
Pranit Bauva
09535f056b bisect--helper: reimplement bisect_autostart shell function in C
Reimplement the `bisect_autostart()` shell function in C and add the
C implementation from `bisect_next()` which was previously left
uncovered.

Add `--bisect-autostart` subcommand to be called from git-bisect.sh.
Using `--bisect-autostart` subcommand is a temporary measure to port
the shell function to C so as to use the existing test suite. As more
functions are ported, this subcommand will be retired and
bisect_autostart() will be called directly by `bisect_state()`.

Change behavior of shell script that returned success when user aborted
the bisection.

Mentored-by: Lars Schneider <larsxschneider@gmail.com>
Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Mentored-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Pranit Bauva <pranit.bauva@gmail.com>
Signed-off-by: Tanushree Tumane <tanushreetumane@gmail.com>
Signed-off-by: Miriam Rubio <mirucam@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-24 12:06:30 -07:00
Denton Liu
d8d3d632f4 hooks--update.sample: use hash-agnostic zero OID
The update sample hook has the zero OID hardcoded as 40 zeros. However,
with the introduction of SHA-256 support, this assumption no longer
holds true. Replace the hardcoded $z40 with a call to

	git hash-object --stdin </dev/null | tr '[0-9a-f]' '0'

so the sample hook becomes hash-agnostic.

Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-23 09:31:45 -07:00
Denton Liu
8c7e505950 hooks--pre-push.sample: use hash-agnostic zero OID
The pre-push sample hook has the zero OID hardcoded as 40 zeros.
However, with the introduction of SHA-256 support, this assumption no
longer holds true. Replace the hardcoded $z40 with a call to

	git hash-object --stdin </dev/null | tr '[0-9a-f]' '0'

so the sample hook becomes hash-agnostic.

Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-23 09:31:45 -07:00
Denton Liu
6a117da6e5 hooks--pre-push.sample: modernize script
The preferred form for a command substitution is $() over ``. Use this
form for the command substitution in the sample hook.

The preferred form for conditional tests is to use `test` over [].
Replace [] with `test`.

Finally, replace all instances of "sha" with "oid".

Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-23 09:31:45 -07:00
Johannes Schindelin
87c86a26de Merge pull request #2831 from dscho/prepare-for-v2.29.0-rc0
Prepare for v2.29.0-rc0
2020-09-23 15:51:38 +02:00
Johannes Schindelin
edc387f0e6 fixup! fscache: teach fscache to use mempool
Needed for the recent mem-pool changes.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2020-09-23 15:03:46 +02:00
Johannes Schindelin
29be755d4f Merge branch 'en/mem-pool'
This merges the `mem_pool` changes (backported on top of v2.28.0) into
Git for Windows' `main` branch early, i.e. before v2.29.0-rc0 is
available, to be able to adjust our `fscache.c` early (which would
otherwise conflict).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2020-09-23 15:00:07 +02:00
Johannes Schindelin
6d05883f95 fixup! clean: remove mount points when possible
Accommodating for Junio's changes to the path quoting machinery.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2020-09-23 14:57:52 +02:00
Johannes Schindelin
ab8c9c83a2 Merge branch 'jc/quote-path-cleanup'
This merges the `quote_path()` fixes (backported on top of v2.28.0) into
Git for Windows' `main` branch early, i.e. before v2.29.0-rc0 is
available, to be able to adjust our `builtin/clean.c` changes early
(which would otherwise conflict).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2020-09-23 14:56:06 +02:00
Elijah Newren
30373b6c6c mem-pool: use consistent pool variable name
About half the function declarations in mem-pool.h used 'struct mem_pool
*pool', while the other half used 'struct mem_pool *mem_pool'.  Make the
code a bit more consistent by just using 'pool' in preference to
'mem_pool' everywhere.

No behavioral changes included; this is just a mechanical rename (though
a line or two was rewrapped as well).

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-23 14:56:04 +02:00
Junio C Hamano
d33371e91a quote: turn 'nodq' parameter into a set of flags
quote_c_style() and its friend quote_two_c_style() both take an
optional "please omit the double quotes around the quoted body"
parameter.  Turn it into a flag word, assign one bit out of it,
and call it CQUOTE_NODQ bit.

No behaviour change intended.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-23 14:56:04 +02:00
Elijah Newren
7188a39e52 mem-pool: use more standard initialization and finalization
A typical memory type, such as strbuf, hashmap, or string_list can be
stored on the stack or embedded within another structure.  mem_pool
cannot be, because of how mem_pool_init() and mem_pool_discard() are
written.  mem_pool_init() does essentially the following (simplified
for purposes of explanation here):

    void mem_pool_init(struct mem_pool **pool...)
    {
        *pool = xcalloc(1, sizeof(*pool));

It seems weird to require that mem_pools can only be accessed through a
pointer.  It also seems slightly dangerous: unlike strbuf_release() or
strbuf_reset() or string_list_clear(), all of which put the data
structure into a state where it can be re-used after the call,
mem_pool_discard(pool) will leave pool pointing at free'd memory.
read-cache (and split-index) are the only current users of mem_pools,
and they haven't fallen into a use-after-free mistake here, but it seems
likely to be problematic for future users especially since several of
the current callers of mem_pool_init() will only call it when the
mem_pool* is not already allocated (i.e. is NULL).

This type of mechanism also prevents finding synchronization
points where one can free existing memory and then resume more
operations.  It would be natural at such points to run something like
    mem_pool_discard(pool...);
and, if necessary,
    mem_pool_init(&pool...);
and then carry on continuing to use the pool.  However, this fails badly
if several objects had a copy of the value of pool from before these
commands; in such a case, those objects won't get the updated value of
pool that mem_pool_init() overwrites pool with and they'll all instead
be reading and writing from free'd memory.

Modify mem_pool_init()/mem_pool_discard() to behave more like
   strbuf_init()/strbuf_release()
or
   string_list_init()/string_list_clear()
In particular: (1) make mem_pool_init() just take a mem_pool* and have
it only worry about allocating struct mp_blocks, not the struct mem_pool
itself, (2) make mem_pool_discard() free the memory that the pool was
responsible for, but leave it in a state where it can be used to
allocate more memory afterward (without the need to call mem_pool_init()
again).

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-23 14:56:04 +02:00
Elijah Newren
5966a5bb40 mem-pool: add convenience functions for strdup and strndup
fast-import had a special mem_pool_strdup() convenience function that I
want to be able to use from the new merge algorithm I am writing.  Move
it from fast-import to mem-pool, and also add a mem_pool_strndup()
while at it that I also want to use.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-23 14:56:04 +02:00
Junio C Hamano
d76055c843 quote: rename misnamed sq_lookup[] to cq_lookup[]
This table is used to see if each byte needs quoting when responding
to a request to C-quote the string, not quoting with single-quote in
the shell style.  Similarly, sq_must_quote() is fed each byte from
the string being C-quoted.

No behaviour change intended.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-23 14:56:03 +02:00
Junio C Hamano
2752ee2648 wt-status: consistently quote paths in "status --short" output
Tracked paths with SP in them were cquoted in "git status --short"
output, but untracked, ignored, and unmerged paths weren't.

The test was stolen from a patch to fix output for the 'untracked'
paths by brian m. carlson, with similar tests added for 'ignored'
ones.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-23 14:56:03 +02:00
Junio C Hamano
57fb202d8c quote_path: code clarification
The implementation we moved from wt-status to enclose a pathname
that has a SP in it inside a dq-pair is a bit convoluted.  It lets
quote_c_style_counted() do its escaping and then

 (1) if the input string got escaped, which is checked by seeing if
     the result begins with a double-quote, declare that we are
     done.  If there wasn't any SP in the input, that is OK, and if
     there was, the result is quoted already so it is OK, too.

 (2) if the input string did not get escaped, and the result has SP
     in it, enclose the whole thing in a dq-pair ourselves.

Instead we can scan the path upfront to see if the input has SP in
it.  If so, we tell quote_c_style_counted() not to enclose its
output in a dq-pair, and we add a dq-pair ourselves.  Whether the
input had bytes that quote_c_style_counted() uses backslash quoting,
this would give us a desired quoted string.  If the input does not
have SP in it, we just let quote_c_style_counted() do its thing as
usual, which would enclose the result in a dq-pair only when needed.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-23 14:56:03 +02:00
Junio C Hamano
40393f2a9e quote_path: optionally allow quoting a path with SP in it
Some code in wt-status.c special case a path with SP in it, which
usually does not have to be c-quoted, and ensure that such a path
does get quoted.  Move the logic to quote_path() and give it a bit
in the flags word, QUOTE_PATH_QUOTE_SP.

No behaviour change intended.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-23 14:56:03 +02:00
Junio C Hamano
0df065fe61 quote_path: give flags parameter to quote_path()
The quote_path() function computes a path (relative to its base
directory) and c-quotes the result if necessary.  Teach it to take a
flags parameter to allow its behaviour to be enriched later.

No behaviour change intended.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-23 14:56:03 +02:00
Junio C Hamano
5f1e0d87f3 quote_path: rename quote_path_relative() to quote_path()
There is no quote_path_absolute() or anything that causes confusion,
and one of the two large consumers already rename the long name
locally with a preprocessor macro.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-23 14:56:03 +02:00
Johannes Schindelin
568c2f1745 Merge pull request #2827 from dscho/rename-t7421-to-make-room
Rename a test to prepare for v2.29.0
2020-09-22 21:48:23 +02:00
Junio C Hamano
e1cfff6765 Sixteenth batch
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-22 12:36:34 -07:00
Junio C Hamano
6854689e65 Merge branch 'ar/fetch-ipversion-in-all'
"git fetch --all --ipv4/--ipv6" forgot to pass the protocol options
to instances of the "git fetch" that talk to individual remotes,
which has been corrected.

* ar/fetch-ipversion-in-all:
  fetch: pass --ipv4 and --ipv6 options to sub-fetches
2020-09-22 12:36:34 -07:00
Junio C Hamano
31b9454170 Merge branch 'dl/complete-format-patch-recent-features'
Update to command line completion (in contrib/)

* dl/complete-format-patch-recent-features:
  contrib/completion: complete options that take refs for format-patch
2020-09-22 12:36:33 -07:00
Junio C Hamano
39149df364 Merge branch 'cs/don-t-pretend-a-failed-remote-set-head-succeeded'
"git remote set-head" that failed still said something that hints
the operation went through, which was misleading.

* cs/don-t-pretend-a-failed-remote-set-head-succeeded:
  remote: don't show success message when set-head fails
2020-09-22 12:36:32 -07:00
Junio C Hamano
221b755f3a Merge branch 'jk/dont-count-existing-objects-twice'
There is a logic to estimate how many objects are in the
repository, which is mean to run once per process invocation, but
it ran every time the estimated value was requested.

* jk/dont-count-existing-objects-twice:
  packfile: actually set approximate_object_count_valid
2020-09-22 12:36:32 -07:00
Junio C Hamano
26a3728bed Merge branch 'al/ref-filter-merged-and-no-merged'
"git for-each-ref" and friends that list refs used to allow only
one --merged or --no-merged to filter them; they learned to take
combination of both kind of filtering.

* al/ref-filter-merged-and-no-merged:
  Doc: prefer more specific file name
  ref-filter: make internal reachable-filter API more precise
  ref-filter: allow merged and no-merged filters
  Doc: cover multiple contains/no-contains filters
  t3201: test multiple branch filter combinations
2020-09-22 12:36:31 -07:00
Junio C Hamano
4d515253af Merge branch 'cd/commit-graph-doc'
Doc update.

* cd/commit-graph-doc:
  commit-graph-format.txt: fix no-parent value
2020-09-22 12:36:30 -07:00