Commit Graph

259 Commits

Author SHA1 Message Date
Junio C Hamano
465e73fff3 Merge branch 'tb/filter-alternate-refs'
When pushing into a repository that borrows its objects from an
alternate object store, "git receive-pack" that responds to the
push request on the other side lists the tips of refs in the
alternate to reduce the amount of objects transferred.  This
sometimes is detrimental when the number of refs in the alternate
is absurdly large, in which case the bandwidth saved in potentially
fewer objects transferred is wasted in excessively large ref
advertisement.  The alternate refs that are advertised are now
configurable with a pair of configuration variables.

* tb/filter-alternate-refs:
  transport.c: introduce core.alternateRefsPrefixes
  transport.c: introduce core.alternateRefsCommand
  transport.c: extract 'fill_alternate_refs_command'
  transport: drop refnames from for_each_alternate_ref
2018-10-19 13:34:08 +09:00
Junio C Hamano
0527fbab68 Merge branch 'jt/avoid-ls-refs'
Over some transports, fetching objects with an exact commit object
name can be done without first seeing the ref advertisements.  The
code has been optimized to exploit this.

* jt/avoid-ls-refs:
  fetch: do not list refs if fetching only hashes
  transport: list refs before fetch if necessary
  transport: do not list refs if possible
  transport: allow skipping of ref listing
2018-10-19 13:34:07 +09:00
Junio C Hamano
fa54cccf1f Merge branch 'jt/non-blob-lazy-fetch'
A partial clone that is configured to lazily fetch missing objects
will on-demand issue a "git fetch" request to the originating
repository to fill not-yet-obtained objects.  The request has been
optimized for requesting a tree object (and not the leaf blob
objects contained in it) by telling the originating repository that
no blobs are needed.

* jt/non-blob-lazy-fetch:
  fetch-pack: exclude blobs when lazy-fetching trees
  fetch-pack: avoid object flags if no_dependents
2018-10-19 13:34:07 +09:00
Jeff King
bdf4276c91 transport: drop refnames from for_each_alternate_ref
None of the current callers use the refname parameter we pass to their
callbacks. In theory somebody _could_ do so, but it's actually quite
weird if you think about it: it's a ref in somebody else's repository.
So the name has no meaning locally, and in fact there may be duplicates
if there are multiple alternates.

The users of this interface really only care about seeing some ref tips,
since that promises that the alternate has the full commit graph
reachable from there. So let's keep the information we pass back to the
bare minimum.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-09 14:30:02 +09:00
Jonathan Tan
0177565148 transport: do not list refs if possible
When all refs to be fetched are exact OIDs, it is possible to perform a
fetch without requiring the remote to list refs if protocol v2 is used.
Teach Git to do this.

This currently has an effect only for lazy fetches done from partial
clones. The change necessary to likewise optimize "git fetch <remote>
<sha-1>" will be done in a subsequent patch.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-07 09:53:15 +09:00
René Scharfe
22a1646511 fetch-pack: load tip_oids eagerly iff needed
tip_oids_contain() lazily loads refs into an oidset at its first call.
It abuses the internal (sub)member .map.tablesize of that oidset to
check if it has done that already.

Determine if the oidset needs to be populated upfront and then do that
instead.  This duplicates a loop, but simplifies the existing one by
separating concerns between the two.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-04 11:12:13 -07:00
René Scharfe
bf73282c0b fetch-pack: factor out is_unmatched_ref()
Move the code to determine if a request is unmatched to its own little
helper.  This allows us to reuse it in a subsequent patch.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-04 11:12:13 -07:00
Jonathan Tan
4c7f9567ea fetch-pack: exclude blobs when lazy-fetching trees
A partial clone with missing trees can be obtained using "git clone
--filter=tree:none <repo>". In such a repository, when a tree needs to
be lazily fetched, any tree or blob it directly or indirectly references
is fetched as well, regardless of whether the original command required
those objects, or if the local repository already had some of them.

This is because the fetch protocol, which the lazy fetch uses, does not
allow clients to request that only the wanted objects be sent, which
would be the ideal solution. This patch implements a partial solution:
specify the "blob:none" filter, somewhat reducing the fetch payload.

This change has no effect when lazily fetching blobs (due to how filters
work). And if lazily fetching a commit (such repositories are difficult
to construct and is not a use case we support very well, but it is
possible), referenced commits and trees are still fetched - only the
blobs are not fetched.

The necessary code change is done in fetch_pack() instead of somewhere
closer to where the "filter" instruction is written to the wire so that
only one part of the code needs to be changed in order for users of all
protocol versions to benefit from this optimization.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-04 06:03:49 -07:00
Jonathan Tan
12f19a9825 fetch-pack: avoid object flags if no_dependents
When fetch_pack() is invoked as part of another Git command (due to a
lazy fetch from a partial clone, for example), it uses object flags that
may already be used by the outer Git command.

The commit that introduced the lazy fetch feature (88e2f9ed8e
("introduce fetch-object: fetch one promisor object", 2017-12-05)) tried
to avoid this overlap, but it did not avoid it totally. It was
successful in avoiding writing COMPLETE, but did not avoid reading
COMPLETE, and did not avoid writing and reading ALTERNATE.

Ensure that no flags are written or read by fetch_pack() in the case
where it is used to perform a lazy fetch. To do this, it is sufficient
to avoid checking completeness of wanted refs (unnecessary in the case
of lazy fetches), and to avoid negotiation-related work (in the current
implementation, already, no negotiation is performed). After that was
done, the lack of overlap was verified by checking all direct and
indirect usages of COMPLETE and ALTERNATE - that they are read or
written only if no_dependents is false.

There are other possible solutions to this issue:

 (1) Split fetch-pack.{c,h} into a flag-using part and a non-flag-using
     part, and whenever no_dependents is set, only use the
     non-flag-using part.
 (2) Make fetch_pack() be able to be used with arbitrary repository
     objects. fetch_pack() should then create its own repository object
     based on the given repository object, with its own object
     hashtable, so that the flags do not conflict.

(1) is possible but invasive - some functions would need to be split;
and such invasiveness would potentially be unnecessary if we ever were
to need (2) anyway. (2) would be useful if we were to support, say,
submodules that were partial clones themselves, but I don't know when or
if the Git project plans to support those.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-04 06:00:53 -07:00
Jeff King
9001dc2a74 convert "oidcmp() != 0" to "!oideq()"
This is the flip side of the previous two patches: checking
for a non-zero oidcmp() can be more strictly expressed as
inequality. Like those patches, we write "!= 0" in the
coccinelle transformation, which covers by isomorphism the
more common:

  if (oidcmp(E1, E2))

As with the previous two patches, this patch can be achieved
almost entirely by running "make coccicheck"; the only
differences are manual line-wrap fixes to match the original
code.

There is one thing to note for anybody replicating this,
though: coccinelle 1.0.4 seems to miss the case in
builtin/tag.c, even though it's basically the same as all
the others. Running with 1.0.7 does catch this, so
presumably it's just a coccinelle bug that was fixed in the
interim.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-29 11:32:49 -07:00
Junio C Hamano
f8ca71870a Merge branch 'ab/fsck-transfer-updates'
The test performed at the receiving end of "git push" to prevent
bad objects from entering repository can be customized via
receive.fsck.* configuration variables; we now have gained a
counterpart to do the same on the "git fetch" side, with
fetch.fsck.* configuration variables.

* ab/fsck-transfer-updates:
  fsck: test and document unknown fsck.<msg-id> values
  fsck: add stress tests for fsck.skipList
  fsck: test & document {fetch,receive}.fsck.* config fallback
  fetch: implement fetch.fsck.*
  transfer.fsckObjects tests: untangle confusing setup
  config doc: elaborate on fetch.fsckObjects security
  config doc: elaborate on what transfer.fsckObjects does
  config doc: unify the description of fsck.* and receive.fsck.*
  config doc: don't describe *.fetchObjects twice
  receive.fsck.<msg-id> tests: remove dead code
2018-08-17 13:09:54 -07:00
Junio C Hamano
b160b6e69d Merge branch 'jt/connectivity-check-after-unshallow'
"git fetch" sometimes failed to update the remote-tracking refs,
which has been corrected.

* jt/connectivity-check-after-unshallow:
  fetch-pack: unify ref in and out param
2018-08-15 15:08:28 -07:00
Junio C Hamano
ea30f539ef Merge branch 'bw/fetch-pack-i18n'
i18n updates.

* bw/fetch-pack-i18n:
  fetch-pack: mark die strings for translation
2018-08-15 15:08:20 -07:00
Junio C Hamano
7c85ee6c58 Merge branch 'jt/fetch-negotiator-skipping'
Add a server-side knob to skip commits in exponential/fibbonacci
stride in an attempt to cover wider swath of history with a smaller
number of iterations, potentially accepting a larger packfile
transfer, instead of going back one commit a time during common
ancestor discovery during the "git fetch" transaction.

* jt/fetch-negotiator-skipping:
  negotiator/skipping: skip commits during fetch
2018-08-02 15:30:46 -07:00
Junio C Hamano
30bf8d9f4f Merge branch 'jt/fetch-nego-tip'
"git fetch" learned a new option "--negotiation-tip" to limit the
set of commits it tells the other end as "have", to reduce wasted
bandwidth and cycles, which would be helpful when the receiving
repository has a lot of refs that have little to do with the
history at the remote it is fetching from.

* jt/fetch-nego-tip:
  fetch-pack: support negotiation tip whitelist
2018-08-02 15:30:43 -07:00
Junio C Hamano
3a2a1dc170 Merge branch 'sb/object-store-lookup'
lookup_commit_reference() and friends have been updated to find
in-core object for a specific in-core repository instance.

* sb/object-store-lookup: (32 commits)
  commit.c: allow lookup_commit_reference to handle arbitrary repositories
  commit.c: allow lookup_commit_reference_gently to handle arbitrary repositories
  tag.c: allow deref_tag to handle arbitrary repositories
  object.c: allow parse_object to handle arbitrary repositories
  object.c: allow parse_object_buffer to handle arbitrary repositories
  commit.c: allow get_cached_commit_buffer to handle arbitrary repositories
  commit.c: allow set_commit_buffer to handle arbitrary repositories
  commit.c: migrate the commit buffer to the parsed object store
  commit-slabs: remove realloc counter outside of slab struct
  commit.c: allow parse_commit_buffer to handle arbitrary repositories
  tag: allow parse_tag_buffer to handle arbitrary repositories
  tag: allow lookup_tag to handle arbitrary repositories
  commit: allow lookup_commit to handle arbitrary repositories
  tree: allow lookup_tree to handle arbitrary repositories
  blob: allow lookup_blob to handle arbitrary repositories
  object: allow lookup_object to handle arbitrary repositories
  object: allow object_as_type to handle arbitrary repositories
  tag: add repository argument to deref_tag
  tag: add repository argument to parse_tag_buffer
  tag: add repository argument to lookup_tag
  ...
2018-08-02 15:30:42 -07:00
Junio C Hamano
af8ac73801 Merge branch 'jt/fetch-pack-negotiator'
Code restructuring and a small fix to transport protocol v2 during
fetching.

* jt/fetch-pack-negotiator:
  fetch-pack: introduce negotiator API
  fetch-pack: move common check and marking together
  fetch-pack: make negotiation-related vars local
  fetch-pack: use ref adv. to prune "have" sent
  fetch-pack: directly end negotiation if ACK ready
  fetch-pack: clear marks before re-marking
  fetch-pack: split up everything_local()
2018-08-02 15:30:41 -07:00
Jonathan Tan
e2842b39f4 fetch-pack: unify ref in and out param
When a user fetches:
 - at least one up-to-date ref and at least one non-up-to-date ref,
 - using HTTP with protocol v0 (or something else that uses the fetch
   command of a remote helper)
some refs might not be updated after the fetch.

This bug was introduced in commit 989b8c4452 ("fetch-pack: put shallow
info in output parameter", 2018-06-28) which allowed transports to
report the refs that they have fetched in a new out-parameter
"fetched_refs". If they do so, transport_fetch_refs() makes this
information available to its caller.

Users of "fetched_refs" rely on the following 3 properties:
 (1) it is the complete list of refs that was passed to
     transport_fetch_refs(),
 (2) it has shallow information (REF_STATUS_REJECT_SHALLOW set if
     relevant), and
 (3) it has updated OIDs if ref-in-want was used (introduced after
     989b8c4452).

In an effort to satisfy (1), whenever transport_fetch_refs()
filters the refs sent to the transport, it re-adds the filtered refs to
whatever the transport supplies before returning it to the user.
However, the implementation in 989b8c4452 unconditionally re-adds the
filtered refs without checking if the transport refrained from reporting
anything in "fetched_refs" (which it is allowed to do), resulting in an
incomplete list, no longer satisfying (1).

An earlier effort to resolve this [1] solved the issue by readding the
filtered refs only if the transport did not refrain from reporting in
"fetched_refs", but after further discussion, it seems that the better
solution is to revert the API change that introduced "fetched_refs".
This API change was first suggested as part of a ref-in-want
implementation that allowed for ref patterns and, thus, there could be
drastic differences between the input refs and the refs actually fetched
[2]; we eventually decided to only allow exact ref names, but this API
change remained even though its necessity was decreased.

Therefore, revert this API change by reverting commit 989b8c4452, and
make receive_wanted_refs() update the OIDs in the sought array (like how
update_shallow() updates shallow information in the sought array)
instead. A test is also included to show that the user-visible bug
discussed at the beginning of this commit message no longer exists.

[1] https://public-inbox.org/git/20180801171806.GA122458@google.com/
[2] https://public-inbox.org/git/86a128c5fb710a41791e7183207c4d64889f9307.1485381677.git.jonathantanmy@google.com/

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-01 15:00:52 -07:00
Ævar Arnfjörð Bjarmason
1362df0d41 fetch: implement fetch.fsck.*
Implement support for fetch.fsck.* corresponding with the existing
receive.fsck.*. This allows for pedantically cloning repositories with
specific issues without turning off fetch.fsckObjects.

One such repository is https://github.com/robbyrussell/oh-my-zsh.git
which before this change will emit this error when cloned with
fetch.fsckObjects:

    error: object 2b7227859263b6aabcc28355b0b994995b7148b6: zeroPaddedFilemode: contains zero-padded file modes
    fatal: Error in object
    fatal: index-pack failed

Now with fetch.fsck.zeroPaddedFilemode=warn we'll warn about that
issue, but the clone will succeed:

    warning: object 2b7227859263b6aabcc28355b0b994995b7148b6: zeroPaddedFilemode: contains zero-padded file modes
    warning: object a18c4d13c2a5fa2d4ecd5346c50e119b999b807d: zeroPaddedFilemode: contains zero-padded file modes
    warning: object 84df066176c8da3fd59b13731a86d90f4f1e5c9d: zeroPaddedFilemode: contains zero-padded file modes

The motivation for this is to be able to turn on fetch.fsckObjects
globally across a fleet of computers but still be able to manually
clone various legacy repositories by either white-listing specific
issues, or better yet whitelist specific objects.

The use of --git-dir=* instead of -C in the tests could be considered
somewhat archaic, but the tests I'm adding here are duplicating the
corresponding receive.* tests with as few changes as possible.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-27 11:36:05 -07:00
Junio C Hamano
88df0fa659 Merge branch 'jt/connectivity-check-after-unshallow'
"git fetch" failed to correctly validate the set of objects it
received when making a shallow history deeper, which has been
corrected.

* jt/connectivity-check-after-unshallow:
  fetch-pack: write shallow, then check connectivity
  fetch-pack: implement ref-in-want
  fetch-pack: put shallow info in output parameter
  fetch: refactor to make function args narrower
  fetch: refactor fetch_refs into two functions
  fetch: refactor the population of peer ref OIDs
  upload-pack: test negotiation with changing repository
  upload-pack: implement ref-in-want
  test-pkt-line: add unpack-sideband subcommand
2018-07-24 14:50:44 -07:00
Brandon Williams
bbb19a8b06 fetch-pack: mark die strings for translation
Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-23 15:59:40 -07:00
Junio C Hamano
00624d608c Merge branch 'sb/object-store-grafts'
The conversion to pass "the_repository" and then "a_repository"
throughout the object access API continues.

* sb/object-store-grafts:
  commit: allow lookup_commit_graft to handle arbitrary repositories
  commit: allow prepare_commit_graft to handle arbitrary repositories
  shallow: migrate shallow information into the object parser
  path.c: migrate global git_path_* to take a repository argument
  cache: convert get_graft_file to handle arbitrary repositories
  commit: convert read_graft_file to handle arbitrary repositories
  commit: convert register_commit_graft to handle arbitrary repositories
  commit: convert commit_graft_pos() to handle arbitrary repositories
  shallow: add repository argument to is_repository_shallow
  shallow: add repository argument to check_shallow_file_for_update
  shallow: add repository argument to register_shallow
  shallow: add repository argument to set_alternate_shallow_file
  commit: add repository argument to lookup_commit_graft
  commit: add repository argument to prepare_commit_graft
  commit: add repository argument to read_graft_file
  commit: add repository argument to register_commit_graft
  commit: add repository argument to commit_graft_pos
  object: move grafts to object parser
  object-store: move object access functions to object-store.h
2018-07-18 12:20:28 -07:00
Jonathan Tan
42cc7485a2 negotiator/skipping: skip commits during fetch
Introduce a new negotiation algorithm used during fetch that skips
commits in an effort to find common ancestors faster. The skips grow
similarly to the Fibonacci sequence as the commit walk proceeds further
away from the tips. The skips may cause unnecessary commits to be
included in the packfile, but the negotiation step typically ends more
quickly.

Usage of this algorithm is guarded behind the configuration flag
fetch.negotiationAlgorithm.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-16 14:51:12 -07:00
Jonathan Tan
3390e42adb fetch-pack: support negotiation tip whitelist
During negotiation, fetch-pack eventually reports as "have" lines all
commits reachable from all refs. Allow the user to restrict the commits
sent in this way by providing a whitelist of tips; only the tips
themselves and their ancestors will be sent.

Both globs and single objects are supported.

This feature is only supported for protocols that support connect or
stateless-connect (such as HTTP with protocol v2).

This will speed up negotiation when the repository has multiple
relatively independent branches (for example, when a repository
interacts with multiple repositories, such as with linux-next [1] and
torvalds/linux [2]), and the user knows which local branch is likely to
have commits in common with the upstream branch they are fetching.

[1] https://kernel.googlesource.com/pub/scm/linux/kernel/git/next/linux-next/
[2] https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux/

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 15:00:41 -07:00
Jonathan Tan
cf1e7c0770 fetch-pack: write shallow, then check connectivity
When fetching, connectivity is checked after the shallow file is
updated. There are 2 issues with this: (1) the connectivity check is
only performed up to ancestors of existing refs (which is not thorough
enough if we were deepening an existing ref in the first place), and (2)
there is no rollback of the shallow file if the connectivity check
fails.

To solve (1), update the connectivity check to check the ancestry chain
completely in the case of a deepening fetch by refraining from passing
"--not --all" when invoking rev-list in connected.c.

To solve (2), have fetch_pack() perform its own connectivity check
before updating the shallow file. To support existing use cases in which
"git fetch-pack" is used to download objects without much regard as to
the connectivity of the resulting objects with respect to the existing
repository, the connectivity check is only done if necessary (that is,
the fetch is not a clone, and the fetch involves shallow/deepen
functionality). "git fetch" still performs its own connectivity check,
preserving correctness but sometimes performing redundant work. This
redundancy is mitigated by the fact that fetch_pack() reports if it has
performed a connectivity check itself, and if the transport supports
connect or stateless-connect, it will bubble up that report so that "git
fetch" knows not to perform the connectivity check in such a case.

This was noticed when a user tried to deepen an existing repository by
fetching with --no-shallow from a server that did not send all necessary
objects - the connectivity check as run by "git fetch" succeeded, but a
subsequent "git fsck" failed.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-03 14:57:44 -07:00
Stefan Beller
a74093da5e tag: add repository argument to deref_tag
Add a repository argument to allow the callers of deref_tag
to be more specific about which repository to act on. This is a small
mechanical change; it doesn't change the implementation to handle
repositories other than the_repository yet.

As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-29 10:43:39 -07:00
Stefan Beller
c1f5eb4962 commit: add repository argument to lookup_commit
Add a repository argument to allow callers of lookup_commit to be more
specific about which repository to handle. This is a small mechanical
change; it doesn't change the implementation to handle repositories
other than the_repository yet.

As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-29 10:43:39 -07:00
Stefan Beller
5abddd1eb7 object: add repository argument to lookup_object
Add a repository argument to allow callers of lookup_object to be more
specific about which repository to handle. This is a small mechanical
change; it doesn't change the implementation to handle repositories
other than the_repository yet.

As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-29 10:43:38 -07:00
Stefan Beller
109cd76dd3 object: add repository argument to parse_object
Add a repository argument to allow the callers of parse_object
to be more specific about which repository to act on. This is a small
mechanical change; it doesn't change the implementation to handle
repositories other than the_repository yet.

As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-29 10:43:38 -07:00
Junio C Hamano
b16b60f71b Merge branch 'sb/object-store-grafts' into sb/object-store-lookup
* sb/object-store-grafts:
  commit: allow lookup_commit_graft to handle arbitrary repositories
  commit: allow prepare_commit_graft to handle arbitrary repositories
  shallow: migrate shallow information into the object parser
  path.c: migrate global git_path_* to take a repository argument
  cache: convert get_graft_file to handle arbitrary repositories
  commit: convert read_graft_file to handle arbitrary repositories
  commit: convert register_commit_graft to handle arbitrary repositories
  commit: convert commit_graft_pos() to handle arbitrary repositories
  shallow: add repository argument to is_repository_shallow
  shallow: add repository argument to check_shallow_file_for_update
  shallow: add repository argument to register_shallow
  shallow: add repository argument to set_alternate_shallow_file
  commit: add repository argument to lookup_commit_graft
  commit: add repository argument to prepare_commit_graft
  commit: add repository argument to read_graft_file
  commit: add repository argument to register_commit_graft
  commit: add repository argument to commit_graft_pos
  object: move grafts to object parser
  object-store: move object access functions to object-store.h
2018-06-29 10:43:28 -07:00
Junio C Hamano
0079732e96 Merge branch 'jk/fetch-all-peeled-fix'
"git fetch-pack --all" used to unnecessarily fail upon seeing an
annotated tag that points at an object other than a commit.

* jk/fetch-all-peeled-fix:
  fetch-pack: test explicitly that --all can fetch tag references pointing to non-commits
  fetch-pack: don't try to fetch peel values with --all
2018-06-28 12:53:32 -07:00
Brandon Williams
733020517a fetch-pack: implement ref-in-want
Implement ref-in-want on the client side so that when a server supports
the "ref-in-want" feature, a client will send "want-ref" lines for each
reference the client wants to fetch.  This feature allows clients to
tolerate inconsistencies that exist when a remote repository's refs
change during the course of negotiation.

This allows a client to request to request a particular ref without
specifying the OID of the ref.  This means that instead of hitting an
error when a ref no longer points at the OID it did at the beginning of
negotiation, negotiation can continue and the value of that ref will be
sent at the termination of negotiation, just before a packfile is sent.

More information on the ref-in-want feature can be found in
Documentation/technical/protocol-v2.txt.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-28 09:33:30 -07:00
Brandon Williams
989b8c4452 fetch-pack: put shallow info in output parameter
Expand the transport fetch method signature, by adding an output
parameter, to allow transports to return information about the refs they
have fetched.  Then communicate shallow status information through this
mechanism instead of by modifying the input list of refs.

This does require clients to sometimes generate the ref map twice: once
from the list of refs provided by the remote (as is currently done) and
potentially once from the new list of refs that the fetch mechanism
provides.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-28 09:33:29 -07:00
Jonathan Tan
ec06283844 fetch-pack: introduce negotiator API
Introduce the new files fetch-negotiator.{h,c}, which contains an API
behind which the details of negotiation are abstracted. Currently, only
one algorithm is available: the existing one.

This patch is written to be easily reviewed: static functions are
moved verbatim from fetch-pack.c to negotiator/default.c, and it can be
seen that the lines replaced by negotiator->X() calls are present in the
X() functions respectively.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-15 08:44:24 -07:00
Jonathan Tan
d093bc7582 fetch-pack: move common check and marking together
When receiving 'ACK <object-id> continue' for a common commit, check if
the commit was already known to be common and mark it as such if not up
front. This should make future refactoring of how the information about
common commits is stored more straightforward.

No visible change intended.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-15 08:44:24 -07:00
Jonathan Tan
d30fe89c37 fetch-pack: make negotiation-related vars local
Reduce the number of global variables by making the priority queue and
the count of non-common commits in it local, passing them as a struct to
various functions where necessary.

This also helps in the case that fetch_pack() is invoked twice in the
same process (when tag following is required when using a transport that
does not support tag following), in that different priority queues will
now be used in each invocation, instead of reusing the possibly
non-empty one.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-15 08:44:23 -07:00
Jonathan Tan
af1c90d13e fetch-pack: use ref adv. to prune "have" sent
In negotiation using protocol v2, fetch-pack sometimes does not make
full use of the information obtained in the ref advertisement:
specifically, that if the server advertises a commit that the client
also has, the client never needs to inform the server that it has the
commit's parents, since it can just tell the server that it has the
advertised commit and it knows that the server can and will infer the
rest.

This is because, in do_fetch_pack_v2(), rev_list_insert_ref_oid() is
invoked before mark_complete_and_common_ref(). This means that if we
have a commit that is both our ref and their ref, it would be enqueued
by rev_list_insert_ref_oid() as SEEN, and since it is thus already SEEN,
mark_complete_and_common_ref() would not enqueue it.

If mark_complete_and_common_ref() were invoked first, as it is in
do_fetch_pack() for protocol v0, then mark_complete_and_common_ref()
would enqueue it with COMMON_REF | SEEN. The addition of COMMON_REF
ensures that its parents are not sent as "have" lines.

Change the order in do_fetch_pack_v2() to be consistent with
do_fetch_pack(), and to avoid sending unnecessary "have" lines.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-15 08:44:23 -07:00
Jonathan Tan
21bcf6e429 fetch-pack: directly end negotiation if ACK ready
When "ACK %s ready" is received, find_common() clears rev_list in an
attempt to stop further "have" lines from being sent [1]. It is much
more readable to explicitly break from the loop instead.

So explicitly break from the loop, and make the clearing of the rev_list
happen unconditionally.

[1] The rationale is further described in the originating commit
f2cba9299b ("fetch-pack: Finish negotation if remote replies "ACK %s
ready"", 2011-03-14).

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-15 08:44:23 -07:00
Jonathan Tan
af008558cc fetch-pack: clear marks before re-marking
If tag following is required when using a transport that does not
support tag following, fetch_pack() will be invoked twice in the same
process, necessitating a clearing of the object flags used by
fetch_pack() sometime during the second invocation. This is currently
done in find_common(), which means that the invocation of
mark_complete_and_common_ref() in do_fetch_pack() is useless.

(This cannot be reproduced with Git alone, because all transports that
come with Git support tag following.)

Therefore, move this clearing from find_common() to its
parent function do_fetch_pack(), right before it calls
mark_complete_and_common_ref().

This has been occurring since the commit that introduced the clearing of
marks, 420e9af498 ("Fix tag following", 2008-03-19).

The corresponding code for protocol v2 in do_fetch_pack_v2() does not
have this problem, as the clearing of flags is done before any marking
(whether by rev_list_insert_ref_oid() or
mark_complete_and_common_ref()).

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-14 11:31:24 -07:00
Jonathan Tan
34c2903456 fetch-pack: split up everything_local()
The function everything_local(), despite its name, also (1) marks
commits as COMPLETE and COMMON_REF and (2) invokes filter_refs() as
important side effects. Extract (1) into its own function
(mark_complete_and_common_ref()) and remove
(2).

The restoring of save_commit_buffer, which was introduced in a1c6d7c1a7
("fetch-pack: restore save_commit_buffer after use", 2017-12-08), is a
concern of the parse_object() call in mark_complete_and_common_ref(), so
it has been moved from the end of everything_local() to the end of
mark_complete_and_common_ref().

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-14 11:31:24 -07:00
Jeff King
e9502c0a7f fetch-pack: don't try to fetch peel values with --all
When "fetch-pack --all" sees a tag-to-blob on the remote, it
tries to fetch both the tag itself ("refs/tags/foo") and the
peeled value that the remote advertises ("refs/tags/foo^{}").
Asking for the object pointed to by the latter can cause
upload-pack to complain with "not our ref", since it does
not mark the peeled objects with the OUR_REF (unless they
were at the tip of some other ref).

Arguably upload-pack _should_ be marking those peeled
objects. But it never has in the past, since clients would
generally just ask for the tag and expect to get the peeled
value along with it. And that's how "git fetch" works, as
well as older versions of "fetch-pack --all".

The problem was introduced by 5f0fc64513 (fetch-pack:
eliminate spurious error messages, 2012-09-09). Before then,
the matching logic was something like:

  if (refname is ill-formed)
     do nothing
  else if (doing --all)
     always consider it matched
  else
     look through list of sought refs for a match

That commit wanted to flip the order of the second two arms
of that conditional. But we ended up with:

  if (refname is ill-formed)
    do nothing
  else
    look through list of sought refs for a match

  if (--all and no match so far)
    always consider it matched

That means tha an ill-formed ref will trigger the --all
conditional block, even though we should just be ignoring
it. We can fix that by having a single "else" with all of
the well-formed logic, that checks the sought refs and
"--all" in the correct order.

Reported-by: Kirill Smelkov <kirr@nexedi.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-11 12:50:58 -07:00
Junio C Hamano
54db5c0e1e Merge branch 'jt/partial-clone-proto-v2'
Transfer protocol v2 learned to support the partial clone.

* jt/partial-clone-proto-v2:
  {fetch,upload}-pack: support filter in protocol v2
  upload-pack: read config when serving protocol v2
  upload-pack: fix error message typo
2018-05-30 14:04:10 +09:00
Junio C Hamano
41267e9697 Merge branch 'bw/server-options'
The transport protocol v2 is getting updated further.

* bw/server-options:
  fetch: send server options when using protocol v2
  ls-remote: send server options when using protocol v2
  serve: introduce the server-option capability
2018-05-23 14:38:15 +09:00
Stefan Beller
102de880d2 path.c: migrate global git_path_* to take a repository argument
Migrate all git_path_* functions that are defined in path.c to take a
repository argument. Unlike other patches in this series, do not use the
 #define trick, as we rewrite the whole function, which is rather small.

This doesn't migrate all the functions, as other builtins have their own
local path functions defined using GIT_PATH_FUNC. So keep that macro
around to serve the other locations.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-18 08:13:10 +09:00
Stefan Beller
c88134870e shallow: add repository argument to is_repository_shallow
Add a repository argument to allow callers of is_repository_shallow
to be more specific about which repository to handle. This is a small
mechanical change; it doesn't change the implementation to handle
repositories other than the_repository yet.

As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-18 08:13:10 +09:00
Stefan Beller
19143f139d shallow: add repository argument to register_shallow
Add a repository argument to allow callers of register_shallow
to be more specific about which repository to handle. This is a small
mechanical change; it doesn't change the implementation to handle
repositories other than the_repository yet.

As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-18 08:13:10 +09:00
Stefan Beller
cbd53a2193 object-store: move object access functions to object-store.h
This should make these functions easier to find and cache.h less
overwhelming to read.

In particular, this moves:
- read_object_file
- oid_object_info
- write_object_file

As a result, most of the codebase needs to #include object-store.h.
In this patch the #include is only added to files that would fail to
compile otherwise.  It would be better to #include wherever
identifiers from the header are used.  That can happen later
when we have better tooling for it.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-16 11:42:03 +09:00
Junio C Hamano
9bfa0f9be3 Merge branch 'bw/protocol-v2'
The beginning of the next-gen transfer protocol.

* bw/protocol-v2: (35 commits)
  remote-curl: don't request v2 when pushing
  remote-curl: implement stateless-connect command
  http: eliminate "# service" line when using protocol v2
  http: don't always add Git-Protocol header
  http: allow providing extra headers for http requests
  remote-curl: store the protocol version the server responded with
  remote-curl: create copy of the service name
  pkt-line: add packet_buf_write_len function
  transport-helper: introduce stateless-connect
  transport-helper: refactor process_connect_service
  transport-helper: remove name parameter
  connect: don't request v2 when pushing
  connect: refactor git_connect to only get the protocol version once
  fetch-pack: support shallow requests
  fetch-pack: perform a fetch using v2
  upload-pack: introduce fetch server command
  push: pass ref prefixes when pushing
  fetch: pass ref prefixes when fetching
  ls-remote: pass ref prefixes when requesting a remote's refs
  transport: convert transport_get_remote_refs to take a list of ref prefixes
  ...
2018-05-08 15:59:16 +09:00
Jonathan Tan
ba95710a3b {fetch,upload}-pack: support filter in protocol v2
The fetch-pack/upload-pack protocol v2 was developed independently of
the filter parameter (used in partial fetches), thus it did not include
support for it. Add support for the filter parameter.

Like in the legacy protocol, the server advertises and supports "filter"
only if uploadpack.allowfilter is configured.

Like in the legacy protocol, the client continues with a warning if
"--filter" is specified, but the server does not advertise it.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-06 13:17:19 +09:00
Junio C Hamano
ea44c0a594 Merge branch 'bw/protocol-v2' into jt/partial-clone-proto-v2
The beginning of the next-gen transfer protocol.

* bw/protocol-v2: (35 commits)
  remote-curl: don't request v2 when pushing
  remote-curl: implement stateless-connect command
  http: eliminate "# service" line when using protocol v2
  http: don't always add Git-Protocol header
  http: allow providing extra headers for http requests
  remote-curl: store the protocol version the server responded with
  remote-curl: create copy of the service name
  pkt-line: add packet_buf_write_len function
  transport-helper: introduce stateless-connect
  transport-helper: refactor process_connect_service
  transport-helper: remove name parameter
  connect: don't request v2 when pushing
  connect: refactor git_connect to only get the protocol version once
  fetch-pack: support shallow requests
  fetch-pack: perform a fetch using v2
  upload-pack: introduce fetch server command
  push: pass ref prefixes when pushing
  fetch: pass ref prefixes when fetching
  ls-remote: pass ref prefixes when requesting a remote's refs
  transport: convert transport_get_remote_refs to take a list of ref prefixes
  ...
2018-05-02 18:54:10 +09:00