Commit Graph

15 Commits

Author SHA1 Message Date
Jonathan Tan
625e7f148e promisor-remote: remove unused variable
The variable core_partial_clone_filter_default has been unused since
fa3d1b63e8 ("promisor-remote: parse remote.*.partialclonefilter",
2019-06-25), when Git was changed to refer to
remote.*.partialclonefilter as the default filter when fetching in a
partial clone, but (perhaps inadvertently) there was no fallback to
core.partialclonefilter.

One alternative is to add the fallback, but the aforementioned change
was made more than a year ago and I have not heard of any complaints
regarding this matter. In addition, there is currently no mention of
core.partialclonefilter in the user documentation. So it seems best to
reaffirm that Git will only support remote.*.partialclonefilter.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-21 22:32:49 -07:00
Jonathan Tan
7ca3c0ac37 promisor-remote: lazy-fetch objects in subprocess
Teach Git to lazy-fetch missing objects in a subprocess instead of doing
it in-process. This allows any fatal errors that occur during the fetch
to be isolated and converted into an error return value, instead of
causing the current command being run to terminate.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-18 16:46:53 -07:00
Junio C Hamano
8f5dc5a4af Merge branch 'jt/avoid-prefetch-when-able-in-diff'
"git diff" in a partial clone learned to avoid lazy loading blob
objects in more casese when they are not needed.

* jt/avoid-prefetch-when-able-in-diff:
  diff: restrict when prefetching occurs
  diff: refactor object read
  diff: make diff_populate_filespec_options struct
  promisor-remote: accept 0 as oid_nr in function
2020-04-28 15:50:04 -07:00
Jeff King
f5914f4b6b parse_config_key(): return subsection len as size_t
We return the length to a subset of a string using an "int *"
out-parameter. This is fine most of the time, as we'd expect config keys
to be relatively short, but it could behave oddly if we had a gigantic
config key. A more appropriate type is size_t.

Let's switch over, which lets our callers use size_t as appropriate
(they are bound by our type because they must pass the out-parameter as
a pointer). This is mostly just a cleanup to make it clear this code
handles long strings correctly. In practice, our config parser already
chokes on long key names (because of a similar int/size_t mixup!).

When doing an int/size_t conversion, we have to be careful that nobody
was trying to assign a negative value to the variable. I manually
confirmed that for each case here. They tend to just feed the result to
xmemdupz() or similar; in a few cases I adjusted the parameter types for
helper functions to make sure the size_t is preserved.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-10 14:44:29 -07:00
Jonathan Tan
db7ed7418b promisor-remote: accept 0 as oid_nr in function
There are 3 callers to promisor_remote_get_direct() that first check if
the number of objects to be fetched is equal to 0. Fold that check into
promisor_remote_get_direct(), and in doing so, be explicit as to what
promisor_remote_get_direct() does if oid_nr is 0 (it returns 0, success,
immediately).

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-02 12:42:32 -07:00
Jonathan Tan
603960b50e promisor-remote: remove fetch_if_missing=0
Commit 6462d5eb9a ("fetch: remove fetch_if_missing=0", 2019-11-08)
strove to remove the need for fetch_if_missing=0 from the fetching
mechanism, so it is plausible to attempt removing fetch_if_missing=0
from the lazy-fetching mechanism in promisor-remote as well.

But doing so reveals a bug - when the server does not send an object
pointed to by a tag object, an infinite loop occurs: Git attempts to
fetch the missing object, which causes a deferencing of all refs (for
negotiation), which causes a lazy fetch of that missing object, and so
on. This bug is because of unnecessary use of the fetch negotiator
during lazy fetching - it is not used after initialization, but it is
still initialized (which causes the dereferencing of all refs).

Thus, when the negotiator is not used during fetching, refrain from
initializing it. Then, remove fetch_if_missing from promisor-remote.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-11-13 11:50:58 +09:00
Emily Shaffer
65904b8b2b promisor-remote: skip move_to_tail when no-op
Previously, when promisor_remote_move_to_tail() is called for a
promisor_remote which is currently the final element in promisors, a
cycle is created in the promisors linked list. This cycle leads to a
double free later on in promisor_remote_clear() when the final element
of the promisors list is removed: promisors is set to promisors->next (a
no-op, as promisors->next == promisors); the previous value of promisors
is free()'d; then the new value of promisors (which is equal to the
previous value of promisors) is also free()'d. This double-free error
was unrecoverable for the user without removing the filter or re-cloning
the repo and hoping to miss this edge case.

Now, when promisor_remote_move_to_tail() would be a no-op, just do a
no-op. In cases of promisor_remote_move_to_tail() where r is not already
at the tail of the list, it works as before.

Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Emily Shaffer <emilyshaffer@google.com>
Acked-by: Christian Couder <christian.couder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-02 14:56:54 +09:00
Christian Couder
4ca9474efa Move core_partial_clone_filter_default to promisor-remote.c
Now that we can have a different default partial clone filter for
each promisor remote, let's hide core_partial_clone_filter_default
as a static in promisor-remote.c to avoid it being use for
anything other than managing backward compatibility.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-25 14:05:38 -07:00
Christian Couder
60b7a92d84 Move repository_format_partial_clone to promisor-remote.c
Now that we have has_promisor_remote() and can use many
promisor remotes, let's hide repository_format_partial_clone
as a static in promisor-remote.c to avoid it being use
for anything other than managing backward compatibility.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-25 14:05:38 -07:00
Christian Couder
db27dca5cf Remove fetch-object.{c,h} in favor of promisor-remote.{c,h}
As fetch_objects() is now used only in promisor-remote.c
and should't be used outside it, let's move it into
promisor-remote.c, make it static there, and remove
fetch-object.{c,h}.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-25 14:05:38 -07:00
Christian Couder
fa3d1b63e8 promisor-remote: parse remote.*.partialclonefilter
This makes it possible to specify a different partial clone
filter for each promisor remote.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-25 14:05:37 -07:00
Christian Couder
faf2abf496 promisor-remote: use repository_format_partial_clone
A remote specified using the extensions.partialClone config
option should be considered a promisor remote too.

For simplicity and to make things predictable, this promisor
remote should be either always the last one we try to get
objects from, or the first one. So it should always be either
at the end of the promisor remote list, or at its start.

We decided to make it the last one we try, because it is
likely that someone using many promisor remotes is doing so
because the other promisor remotes are better for some reason
(maybe they are closer or faster for some kind of objects)
than the origin, and the origin is likely to be the remote
specified by extensions.partialClone.

This justification is not very strong, but one choice had to
be made, and anyway the long term plan should be to make the
order somehow fully configurable.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-25 14:05:37 -07:00
Christian Couder
9cfebc1f3b promisor-remote: add promisor_remote_reinit()
We will need to reinitialize the promisor remote configuration
as we will make some changes to it in a later commit.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-25 14:05:37 -07:00
Christian Couder
9e27beaa23 promisor-remote: implement promisor_remote_get_direct()
This is implemented for now by calling fetch_objects(). It fetches
from all the promisor remotes.

Helped-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Helped-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-25 14:05:37 -07:00
Christian Couder
48de315817 Add initial support for many promisor remotes
The promisor-remote.{c,h} files will contain functions to
manage many promisor remotes.

We expect that there will not be a lot of promisor remotes,
so it is ok to use a simple linked list to manage them.

Helped-by: Jeff King <peff@peff.net>
Helped-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-25 14:05:37 -07:00