introduce fetch-object: fetch one promisor object
Introduce fetch-object, providing the ability to fetch one object from a
promisor remote.
This uses fetch-pack. To do this, the transport mechanism has been
updated with 2 flags, "from-promisor" to indicate that the resulting
pack comes from a promisor remote (and thus should be annotated as such
by index-pack), and "no-dependents" to indicate that only the objects
themselves need to be fetched (but fetching additional objects is
nevertheless safe).
Whenever "no-dependents" is used, fetch-pack will refrain from using any
object flags, because it is most likely invoked as part of a dynamic
object fetch by another Git command (which may itself use object flags).
An alternative to this is to leave fetch-pack alone, and instead update
the allocation of flags so that fetch-pack's flags never overlap with
any others, but this will end up shrinking the number of flags available
to nearly every other Git command (that is, every Git command that
accesses objects), so the approach in this commit was used instead.
This will be tested in a subsequent commit.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-05 17:58:49 +01:00
|
|
|
#include "cache.h"
|
|
|
|
#include "packfile.h"
|
|
|
|
#include "pkt-line.h"
|
|
|
|
#include "strbuf.h"
|
|
|
|
#include "transport.h"
|
|
|
|
#include "fetch-object.h"
|
|
|
|
|
2017-12-08 16:58:47 +01:00
|
|
|
static void fetch_refs(const char *remote_name, struct ref *ref)
|
introduce fetch-object: fetch one promisor object
Introduce fetch-object, providing the ability to fetch one object from a
promisor remote.
This uses fetch-pack. To do this, the transport mechanism has been
updated with 2 flags, "from-promisor" to indicate that the resulting
pack comes from a promisor remote (and thus should be annotated as such
by index-pack), and "no-dependents" to indicate that only the objects
themselves need to be fetched (but fetching additional objects is
nevertheless safe).
Whenever "no-dependents" is used, fetch-pack will refrain from using any
object flags, because it is most likely invoked as part of a dynamic
object fetch by another Git command (which may itself use object flags).
An alternative to this is to leave fetch-pack alone, and instead update
the allocation of flags so that fetch-pack's flags never overlap with
any others, but this will end up shrinking the number of flags available
to nearly every other Git command (that is, every Git command that
accesses objects), so the approach in this commit was used instead.
This will be tested in a subsequent commit.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-05 17:58:49 +01:00
|
|
|
{
|
|
|
|
struct remote *remote;
|
|
|
|
struct transport *transport;
|
2017-12-08 16:27:14 +01:00
|
|
|
int original_fetch_if_missing = fetch_if_missing;
|
introduce fetch-object: fetch one promisor object
Introduce fetch-object, providing the ability to fetch one object from a
promisor remote.
This uses fetch-pack. To do this, the transport mechanism has been
updated with 2 flags, "from-promisor" to indicate that the resulting
pack comes from a promisor remote (and thus should be annotated as such
by index-pack), and "no-dependents" to indicate that only the objects
themselves need to be fetched (but fetching additional objects is
nevertheless safe).
Whenever "no-dependents" is used, fetch-pack will refrain from using any
object flags, because it is most likely invoked as part of a dynamic
object fetch by another Git command (which may itself use object flags).
An alternative to this is to leave fetch-pack alone, and instead update
the allocation of flags so that fetch-pack's flags never overlap with
any others, but this will end up shrinking the number of flags available
to nearly every other Git command (that is, every Git command that
accesses objects), so the approach in this commit was used instead.
This will be tested in a subsequent commit.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-05 17:58:49 +01:00
|
|
|
|
2017-12-08 16:27:14 +01:00
|
|
|
fetch_if_missing = 0;
|
introduce fetch-object: fetch one promisor object
Introduce fetch-object, providing the ability to fetch one object from a
promisor remote.
This uses fetch-pack. To do this, the transport mechanism has been
updated with 2 flags, "from-promisor" to indicate that the resulting
pack comes from a promisor remote (and thus should be annotated as such
by index-pack), and "no-dependents" to indicate that only the objects
themselves need to be fetched (but fetching additional objects is
nevertheless safe).
Whenever "no-dependents" is used, fetch-pack will refrain from using any
object flags, because it is most likely invoked as part of a dynamic
object fetch by another Git command (which may itself use object flags).
An alternative to this is to leave fetch-pack alone, and instead update
the allocation of flags so that fetch-pack's flags never overlap with
any others, but this will end up shrinking the number of flags available
to nearly every other Git command (that is, every Git command that
accesses objects), so the approach in this commit was used instead.
This will be tested in a subsequent commit.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-05 17:58:49 +01:00
|
|
|
remote = remote_get(remote_name);
|
|
|
|
if (!remote->url[0])
|
|
|
|
die(_("Remote with no URL"));
|
|
|
|
transport = transport_get(remote, remote->url[0]);
|
|
|
|
|
|
|
|
transport_set_option(transport, TRANS_OPT_FROM_PROMISOR, "1");
|
|
|
|
transport_set_option(transport, TRANS_OPT_NO_DEPENDENTS, "1");
|
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 22:13:20 +02:00
|
|
|
transport_fetch_refs(transport, ref);
|
2017-12-08 16:27:14 +01:00
|
|
|
fetch_if_missing = original_fetch_if_missing;
|
introduce fetch-object: fetch one promisor object
Introduce fetch-object, providing the ability to fetch one object from a
promisor remote.
This uses fetch-pack. To do this, the transport mechanism has been
updated with 2 flags, "from-promisor" to indicate that the resulting
pack comes from a promisor remote (and thus should be annotated as such
by index-pack), and "no-dependents" to indicate that only the objects
themselves need to be fetched (but fetching additional objects is
nevertheless safe).
Whenever "no-dependents" is used, fetch-pack will refrain from using any
object flags, because it is most likely invoked as part of a dynamic
object fetch by another Git command (which may itself use object flags).
An alternative to this is to leave fetch-pack alone, and instead update
the allocation of flags so that fetch-pack's flags never overlap with
any others, but this will end up shrinking the number of flags available
to nearly every other Git command (that is, every Git command that
accesses objects), so the approach in this commit was used instead.
This will be tested in a subsequent commit.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-12-05 17:58:49 +01:00
|
|
|
}
|
2017-12-08 16:58:47 +01:00
|
|
|
|
|
|
|
void fetch_object(const char *remote_name, const unsigned char *sha1)
|
|
|
|
{
|
|
|
|
struct ref *ref = alloc_ref(sha1_to_hex(sha1));
|
|
|
|
hashcpy(ref->old_oid.hash, sha1);
|
|
|
|
fetch_refs(remote_name, ref);
|
|
|
|
}
|
|
|
|
|
|
|
|
void fetch_objects(const char *remote_name, const struct oid_array *to_fetch)
|
|
|
|
{
|
|
|
|
struct ref *ref = NULL;
|
|
|
|
int i;
|
|
|
|
|
|
|
|
for (i = 0; i < to_fetch->nr; i++) {
|
|
|
|
struct ref *new_ref = alloc_ref(oid_to_hex(&to_fetch->oid[i]));
|
|
|
|
oidcpy(&new_ref->old_oid, &to_fetch->oid[i]);
|
|
|
|
new_ref->next = ref;
|
|
|
|
ref = new_ref;
|
|
|
|
}
|
|
|
|
fetch_refs(remote_name, ref);
|
|
|
|
}
|