Commit Graph

61161 Commits

Author SHA1 Message Date
Jeff King
56d5dde752 shortlog: parse trailer idents
Trailers don't necessarily contain name/email identity values, so
shortlog has so far treated them as opaque strings. However, since many
trailers do contain identities, it's useful to treat them as such when
they can be parsed. That lets "-e" work as usual, as well as mailmap.

When they can't be parsed, we'll continue with the old behavior of
treating them as a single string (there's no new test for that here,
since the existing tests cover a trailer like this).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-27 12:21:05 -07:00
Jeff King
87abb96222 shortlog: rename parse_stdin_ident()
This function is actually useful for parsing any identity, whether from
stdin or not. We'll need it for handling trailers.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-27 12:21:05 -07:00
Jeff King
f17b0b99bf shortlog: de-duplicate trailer values
The current documentation is vague about what happens with
--group=trailer:signed-off-by when we see a commit with:

  Signed-off-by: One
  Signed-off-by: Two
  Signed-off-by: One

We clearly should credit both "One" and "Two", but should "One" get
credited twice? The current code does so, but mostly because that was
the easiest thing to do. It's probably more useful to count each commit
at most once. This will become especially important when we allow
values from multiple sources in a future patch.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-27 12:21:05 -07:00
Jeff King
47beb37bc6 shortlog: match commit trailers with --group
If a project uses commit trailers, this patch lets you use
shortlog to see who is performing each action. For example,
running:

  git shortlog -ns --group=trailer:reviewed-by

in git.git shows who has reviewed. You can even use a custom
format to see things like who has helped whom:

  git shortlog --format="...helped %an (%ad)" \
               --group=trailer:helped-by

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-27 12:21:05 -07:00
Jeff King
f0939a0eb1 trailer: add interface for iterating over commit trailers
The trailer code knows how to parse out the trailers and re-format them,
but there's no easy way to iterate over the trailers (you can use
trailer_info, but you have to then do a bunch of extra parsing).

Let's add an iteration interface that makes this easy to do.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-27 12:21:05 -07:00
Jeff King
92338c450b shortlog: add grouping option
In preparation for adding more grouping types, let's refactor the
committer/author grouping code and add a user-facing option that binds
them together. In particular:

  - the main option is now "--group", to make it clear
    that the various group types are mutually exclusive. The
    "--committer" option is an alias for "--group=committer".

  - we keep an enum rather than a binary flag, to prepare
    for more values

  - we prefer switch statements to ternary assignment, since
    other group types will need more custom code

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-27 12:21:05 -07:00
Johannes Schindelin
f33f2d3d54 t9902: avoid using the branch name master
The completion tests used that name unnecessarily, and it is a
non-inclusive term, so let's avoid using it here.

Since three of the touched test cases make use of the fact that two of
the branch names (`master` and `maint`) start with the same letter (or
even with the same two letters), we choose to replace the use of
`master` by a name that also has that property: `main`.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-26 17:03:29 -07:00
Johannes Schindelin
b6211b89eb tests: avoid variations of the master branch name
The term `master` has a loaded history that serves as a constant
reminder of racial injustice. The Git project has no desire to
perpetuate this and already started avoiding it.

The test suite uses variations of this name for branches other than the
default one. Apart from t3200, where we just addressed this in the
previous commit, those instances can be renamed in an automated manner
because they do not require any changes outside of the test script, so
let's do that.

Seeing as the touched branches have very little (if anything) to do with
the default branch, we choose to use a completely separate naming
scheme: `topic_<number>` (it cannot be `topic-<number>` because t5515
uses the `test_oid` machinery with the term, and that machinery uses
shell variables internally, whose names cannot contain dashes).

This trick was performed by this (GNU) sed invocation:

	$ sed -i 's/master\([a-z0-9]\)/topic_\1/g' t/t*.sh

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-26 17:03:29 -07:00
René Scharfe
5336d50696 ref-filter: plug memory leak in reach_filter()
21bf933928 (ref-filter: allow merged and no-merged filters, 2020-09-15)
added an early return to reach_filter().  Avoid leaking the memory of a
then unused array by postponing its allocation until we know we need it.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-26 15:39:49 -07:00
Ákos Uzonyi
0bc18daa2f completion: complete refs after 'git restore -s'
Currently only the long version (--source=) supports completion.

Add completion support to the short (-s) option too.

Signed-off-by: Ákos Uzonyi <uzonyi.akos@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-26 15:30:05 -07:00
Ákos Uzonyi
c09d1280f7 completion: use "prev" variable instead of introducing "prevword"
In both _git_checkout and _git_switch a new "prevword" variable were
introduced, however the "prev" variable already contains the last word.

The "prevword" variable is replaced with "prev", and the case is moved
to the beginning of the function, like it's done in many other places
(e.g. _git_commit). Also the indentaion of the case is fixed.

Signed-off-by: Ákos Uzonyi <uzonyi.akos@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-26 15:30:03 -07:00
Junio C Hamano
9bc233ae1c Seventeenth batch
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 15:25:42 -07:00
Junio C Hamano
0335915690 Merge branch 'jk/diff-highlight-blank-match-fix'
"diff-highlight" (in contrib/) had a logic to flush its output upon
seeing a blank line but the way it detected a blank line was broken.

* jk/diff-highlight-blank-match-fix:
  diff-highlight: correctly match blank lines for flush
2020-09-25 15:25:42 -07:00
Junio C Hamano
b5847b9fab Merge branch 'hx/push-atomic-with-cert'
"git push" that wants to be atomic and wants to send push
certificate learned not to prepare and sign the push certificate
when it fails the local check (hence due to atomicity it is known
that no certificate is needed).

* hx/push-atomic-with-cert:
  send-pack: run GPG after atomic push checking
2020-09-25 15:25:41 -07:00
Junio C Hamano
407d914521 Merge branch 'rs/misc-cleanups'
Code cleanup.

* rs/misc-cleanups:
  pack-write: use hashwrite_be32() in write_idx_file()
2020-09-25 15:25:41 -07:00
Junio C Hamano
9f4588d72b Merge branch 'ld/p4-unshelve-fix'
The "unshelve" subcommand of "git p4" used incorrectly used
commit^N where it meant to say commit~N to name the Nth generation
ancestor, which has been corrected.

* ld/p4-unshelve-fix:
  git-p4: use HEAD~$n to find parent commit for unshelve
  git-p4 unshelve: adding a commit breaks git-p4 unshelve
2020-09-25 15:25:40 -07:00
Junio C Hamano
6c430a647c Merge branch 'jx/proc-receive-hook'
"git receive-pack" that accepts requests by "git push" learned to
outsource most of the ref updates to the new "proc-receive" hook.

* jx/proc-receive-hook:
  doc: add documentation for the proc-receive hook
  transport: parse report options for tracking refs
  t5411: test updates of remote-tracking branches
  receive-pack: new config receive.procReceiveRefs
  doc: add document for capability report-status-v2
  New capability "report-status-v2" for git-push
  receive-pack: feed report options to post-receive
  receive-pack: add new proc-receive hook
  t5411: add basic test cases for proc-receive hook
  transport: not report a non-head push as a branch
2020-09-25 15:25:39 -07:00
Junio C Hamano
48794acc50 Merge branch 'ds/maintenance-part-1'
A "git gc"'s big brother has been introduced to take care of more
repository maintenance tasks, not limited to the object database
cleaning.

* ds/maintenance-part-1:
  maintenance: add trace2 regions for task execution
  maintenance: add auto condition for commit-graph task
  maintenance: use pointers to check --auto
  maintenance: create maintenance.<task>.enabled config
  maintenance: take a lock on the objects directory
  maintenance: add --task option
  maintenance: add commit-graph task
  maintenance: initialize task array
  maintenance: replace run_auto_gc()
  maintenance: add --quiet option
  maintenance: create basic maintenance runner
2020-09-25 15:25:38 -07:00
Junio C Hamano
0512eabd91 sequencer: stop abbreviating stopped-sha file
The object name written to this file is not exposed to end-users and
the only reader of this file immediately expands it back to a full
object name.  Stop abbreviating while writing, and expect a full
object name while reading, which simplifies the code a bit.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 14:11:12 -07:00
Junio C Hamano
9f0be82123 t1506: rev-parse A..B and A...B
Because these constructs can be used to parse user input to be
passed to rev-list --objects, e.g.

	range=$(git rev-parse v1.0..v2.0) &&
	git rev-list --objects $range | git pack-objects --stdin

the endpoints (v1.0 and v2.0 in the example) are shown without
peeling them to underlying commits, even when they are annotated
tags.  Make sure it stays that way.

While at it, ensure "rev-parse A...B" also keeps the endpoints A and
B unpeeled, even though the negative side (i.e. the merge-base
between A and B) has to become a commit.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 14:09:17 -07:00
Jeff King
eb049759fb protocol: re-enable v2 protocol by default
Protocol v2 became the default in v2.26.0 via 684ceae32d (fetch: default
to protocol version 2, 2019-12-23). More widespread use turned up a
regression in negotiation. That was fixed in v2.27.0 via 4fa3f00abb
(fetch-pack: in protocol v2, in_vain only after ACK, 2020-04-27), but we
also reverted the default to v0 as a precuation in 11c7f2a30b (Revert
"fetch: default to protocol version 2", 2020-04-22).

In v2.28.0, we re-enabled it for experimental users with 3697caf4b9
(config: let feature.experimental imply protocol.version=2, 2020-05-20)
and haven't heard any complaints. v2.28 has only been out for 2 months,
but I'd generally expect people turning on feature.experimental to also
stay pretty up-to-date. So we're not likely to collect much more data by
waiting. In addition, we have no further reports from people running
v2.26.0, and of course some people have been setting protocol.version
manually for ages.

Let's move forward with v2 as the default again. It's possible there are
still lurking bugs, but we won't know until it gets more widespread use.
And we can find and squash them just like any other bug at this point.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-25 11:40:42 -07:00
Derrick Stolee
2fec604f8d maintenance: add start/stop subcommands
Add new subcommands to 'git maintenance' that start or stop background
maintenance using 'cron', when available. This integration is as simple
as I could make it, barring some implementation complications.

The schedule is laid out as follows:

  0 1-23 * * *   $cmd maintenance run --schedule=hourly
  0 0    * * 1-6 $cmd maintenance run --schedule=daily
  0 0    * * 0   $cmd maintenance run --schedule=weekly

where $cmd is a properly-qualified 'git for-each-repo' execution:

$cmd=$path/git --exec-path=$path for-each-repo --config=maintenance.repo

where $path points to the location of the Git executable running 'git
maintenance start'. This is critical for systems with multiple versions
of Git. Specifically, macOS has a system version at '/usr/bin/git' while
the version that users can install resides at '/usr/local/bin/git'
(symlinked to '/usr/local/libexec/git-core/git'). This will also use
your locally-built version if you build and run this in your development
environment without installing first.

This conditional schedule avoids having cron launch multiple 'git
for-each-repo' commands in parallel. Such parallel commands would likely
lead to the 'hourly' and 'daily' tasks competing over the object
database lock. This could lead to to some tasks never being run! Since
the --schedule=<frequency> argument will run all tasks with _at least_
the given frequency, the daily runs will also run the hourly tasks.
Similarly, the weekly runs will also run the daily and hourly tasks.

The GIT_TEST_CRONTAB environment variable is not intended for users to
edit, but instead as a way to mock the 'crontab [-l]' command. This
variable is set in test-lib.sh to avoid a future test from accidentally
running anything with the cron integration from modifying the user's
schedule. We use GIT_TEST_CRONTAB='test-tool crontab <file>' in our
tests to check how the schedule is modified in 'git maintenance
(start|stop)' commands.

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
0c18b70081 maintenance: add [un]register subcommands
In preparation for launching background maintenance from the 'git
maintenance' builtin, create register/unregister subcommands. These
commands update the new 'maintenance.repos' config option in the global
config so the background maintenance job knows which repositories to
maintain.

These commands allow users to add a repository to the background
maintenance list without disrupting the actual maintenance mechanism.

For example, a user can run 'git maintenance register' when no
background maintenance is running and it will not start the background
maintenance. A later update to start running background maintenance will
then pick up this repository automatically.

The opposite example is that a user can run 'git maintenance unregister'
to remove the current repository from background maintenance without
halting maintenance for other repositories.

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
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
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
Junio C Hamano
e1cfff6765 Sixteenth batch
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-22 12:36:34 -07:00