From: Jonathan Tan <jonathantanmy@google.com>
To: git@vger.kernel.org
Cc: Jonathan Tan <jonathantanmy@google.com>, gitster@pobox.com
Subject: [PATCH v2 1/7] negotiator/null: add null fetch negotiator
Date: Tue, 11 Aug 2020 15:52:16 -0700 [thread overview]
Message-ID: <35bdd372ae3691f54775dd616576e8ed6d68f1d3.1597184949.git.jonathantanmy@google.com> (raw)
In-Reply-To: <cover.1597184948.git.jonathantanmy@google.com>
Add a null fetch negotiator. This is introduced to allow partial clones
to skip the unneeded negotiation step when fetching missing objects
using a "git fetch" subprocess. (The implementation of spawning a "git
fetch" subprocess will be done in a subsequent patch.) But this can also
be useful for end users, e.g. as a blunt fix for object corruption.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
---
Documentation/config/fetch.txt | 5 +++-
Makefile | 1 +
fetch-negotiator.c | 5 ++++
negotiator/null.c | 44 ++++++++++++++++++++++++++++++++
negotiator/null.h | 8 ++++++
repo-settings.c | 2 ++
repository.h | 1 +
t/t5554-null-fetch-negotiator.sh | 22 ++++++++++++++++
8 files changed, 87 insertions(+), 1 deletion(-)
create mode 100644 negotiator/null.c
create mode 100644 negotiator/null.h
create mode 100755 t/t5554-null-fetch-negotiator.sh
diff --git a/Documentation/config/fetch.txt b/Documentation/config/fetch.txt
index 0aaa05e8c0..09aff404be 100644
--- a/Documentation/config/fetch.txt
+++ b/Documentation/config/fetch.txt
@@ -60,7 +60,10 @@ fetch.negotiationAlgorithm::
sent when negotiating the contents of the packfile to be sent by the
server. Set to "skipping" to use an algorithm that skips commits in an
effort to converge faster, but may result in a larger-than-necessary
- packfile; The default is "default" which instructs Git to use the default algorithm
+ packfile; or set to "null" to not send any information at all, which
+ will almost certainly result in a larger-than-necessary packfile, but
+ will skip the negotiation step.
+ The default is "default" which instructs Git to use the default algorithm
that never skips commits (unless the server has acknowledged it or one
of its descendants). If `feature.experimental` is enabled, then this
setting defaults to "skipping".
diff --git a/Makefile b/Makefile
index 372139f1f2..297ea5e517 100644
--- a/Makefile
+++ b/Makefile
@@ -917,6 +917,7 @@ LIB_OBJS += mergesort.o
LIB_OBJS += midx.o
LIB_OBJS += name-hash.o
LIB_OBJS += negotiator/default.o
+LIB_OBJS += negotiator/null.o
LIB_OBJS += negotiator/skipping.o
LIB_OBJS += notes-cache.o
LIB_OBJS += notes-merge.o
diff --git a/fetch-negotiator.c b/fetch-negotiator.c
index 0a1357dc9d..e2ecbe4367 100644
--- a/fetch-negotiator.c
+++ b/fetch-negotiator.c
@@ -2,6 +2,7 @@
#include "fetch-negotiator.h"
#include "negotiator/default.h"
#include "negotiator/skipping.h"
+#include "negotiator/null.h"
#include "repository.h"
void fetch_negotiator_init(struct repository *r,
@@ -13,6 +14,10 @@ void fetch_negotiator_init(struct repository *r,
skipping_negotiator_init(negotiator);
return;
+ case FETCH_NEGOTIATION_NULL:
+ null_negotiator_init(negotiator);
+ return;
+
case FETCH_NEGOTIATION_DEFAULT:
default:
default_negotiator_init(negotiator);
diff --git a/negotiator/null.c b/negotiator/null.c
new file mode 100644
index 0000000000..1bd834f121
--- /dev/null
+++ b/negotiator/null.c
@@ -0,0 +1,44 @@
+#include "cache.h"
+#include "null.h"
+#include "../commit.h"
+#include "../fetch-negotiator.h"
+
+static void known_common(struct fetch_negotiator *n, struct commit *c)
+{
+ /* do nothing */
+}
+
+static void add_tip(struct fetch_negotiator *n, struct commit *c)
+{
+ /* do nothing */
+}
+
+static const struct object_id *next(struct fetch_negotiator *n)
+{
+ return NULL;
+}
+
+static int ack(struct fetch_negotiator *n, struct commit *c)
+{
+ /*
+ * This negotiator does not emit any commits, so there is no commit to
+ * be acknowledged. If there is any ack, there is a bug.
+ */
+ BUG("ack with null negotiator, which does not emit any commits");
+ return 0;
+}
+
+static void release(struct fetch_negotiator *n)
+{
+ /* nothing to release */
+}
+
+void null_negotiator_init(struct fetch_negotiator *negotiator)
+{
+ negotiator->known_common = known_common;
+ negotiator->add_tip = add_tip;
+ negotiator->next = next;
+ negotiator->ack = ack;
+ negotiator->release = release;
+ negotiator->data = NULL;
+}
diff --git a/negotiator/null.h b/negotiator/null.h
new file mode 100644
index 0000000000..96713f280e
--- /dev/null
+++ b/negotiator/null.h
@@ -0,0 +1,8 @@
+#ifndef NEGOTIATOR_NULL_H
+#define NEGOTIATOR_NULL_H
+
+struct fetch_negotiator;
+
+void null_negotiator_init(struct fetch_negotiator *negotiator);
+
+#endif
diff --git a/repo-settings.c b/repo-settings.c
index 0918408b34..a8c7e1edd7 100644
--- a/repo-settings.c
+++ b/repo-settings.c
@@ -39,6 +39,8 @@ void prepare_repo_settings(struct repository *r)
if (!repo_config_get_string(r, "fetch.negotiationalgorithm", &strval)) {
if (!strcasecmp(strval, "skipping"))
r->settings.fetch_negotiation_algorithm = FETCH_NEGOTIATION_SKIPPING;
+ else if (!strcasecmp(strval, "null"))
+ r->settings.fetch_negotiation_algorithm = FETCH_NEGOTIATION_NULL;
else
r->settings.fetch_negotiation_algorithm = FETCH_NEGOTIATION_DEFAULT;
}
diff --git a/repository.h b/repository.h
index 3c1f7d54bd..f72911a185 100644
--- a/repository.h
+++ b/repository.h
@@ -23,6 +23,7 @@ enum fetch_negotiation_setting {
FETCH_NEGOTIATION_NONE = 0,
FETCH_NEGOTIATION_DEFAULT = 1,
FETCH_NEGOTIATION_SKIPPING = 2,
+ FETCH_NEGOTIATION_NULL = 3,
};
struct repo_settings {
diff --git a/t/t5554-null-fetch-negotiator.sh b/t/t5554-null-fetch-negotiator.sh
new file mode 100755
index 0000000000..09a8f0d608
--- /dev/null
+++ b/t/t5554-null-fetch-negotiator.sh
@@ -0,0 +1,22 @@
+#!/bin/sh
+
+test_description='test null fetch negotiator'
+. ./test-lib.sh
+
+test_expect_success 'null negotiator does not emit any "have"' '
+ rm -f trace &&
+
+ test_create_repo server &&
+ test_commit -C server to_fetch &&
+
+ test_create_repo client &&
+ test_commit -C client we_have &&
+
+ test_config -C client fetch.negotiationalgorithm null &&
+ GIT_TRACE_PACKET="$(pwd)/trace" git -C client fetch "$(pwd)/server" &&
+
+ ! grep "fetch> have" trace &&
+ grep "fetch> done" trace
+'
+
+test_done
--
2.28.0.236.gb10cc79966-goog
next prev parent reply other threads:[~2020-08-11 22:52 UTC|newest]
Thread overview: 57+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-24 22:38 [RFC PATCH] Modify fetch-pack to no longer die on error? Jonathan Tan
2020-07-24 23:07 ` Junio C Hamano
2020-07-24 23:11 ` Junio C Hamano
2020-07-25 21:41 ` Jeff King
2020-07-25 23:01 ` Junio C Hamano
2020-07-27 17:11 ` Jeff King
2020-07-28 19:23 ` Jonathan Tan
2020-07-28 20:08 ` Jeff King
2020-07-29 18:53 ` Jonathan Tan
2020-07-29 19:29 ` Jeff King
2020-07-29 19:02 ` Junio C Hamano
2020-07-29 22:55 ` Jonathan Tan
2020-08-05 1:20 ` [RFC PATCH 0/7] Lazy fetch with subprocess Jonathan Tan
2020-08-05 1:20 ` [RFC PATCH 1/7] fetch-pack: allow NULL negotiator->add_tip Jonathan Tan
2020-08-05 19:53 ` Junio C Hamano
2020-08-07 20:53 ` Jonathan Tan
2020-08-05 1:20 ` [RFC PATCH 2/7] fetch-pack: allow NULL negotiator->known_common Jonathan Tan
2020-08-05 20:08 ` Junio C Hamano
2020-08-05 22:11 ` Junio C Hamano
2020-08-07 20:59 ` Jonathan Tan
2020-08-05 1:20 ` [RFC PATCH 3/7] negotiator/null: add null fetch negotiator Jonathan Tan
2020-08-05 1:20 ` [RFC PATCH 4/7] fetch: --stdin Jonathan Tan
2020-08-05 20:33 ` Junio C Hamano
2020-08-07 21:10 ` Jonathan Tan
2020-08-07 21:58 ` Junio C Hamano
2020-08-07 21:10 ` Jonathan Tan
2020-08-05 1:20 ` [RFC PATCH 5/7] fetch: submodule config Jonathan Tan
2020-08-05 1:20 ` [RFC PATCH 6/7] fetch: only populate existing_refs if needed Jonathan Tan
2020-08-05 1:20 ` [RFC PATCH 7/7] promisor-remote: use subprocess to fetch Jonathan Tan
2020-08-11 22:52 ` [PATCH v2 0/7] Lazy fetch with subprocess Jonathan Tan
2020-08-11 22:52 ` Jonathan Tan [this message]
2020-08-12 12:55 ` [PATCH v2 1/7] negotiator/null: add null fetch negotiator Derrick Stolee
2020-08-12 16:44 ` Junio C Hamano
2020-08-12 17:29 ` Jonathan Tan
2020-08-11 22:52 ` [PATCH v2 2/7] fetch: allow refspecs specified through stdin Jonathan Tan
2020-08-11 22:52 ` [PATCH v2 3/7] fetch: avoid reading submodule config until needed Jonathan Tan
2020-08-12 17:34 ` Junio C Hamano
2020-08-11 22:52 ` [PATCH v2 4/7] fetch: only populate existing_refs if needed Jonathan Tan
2020-08-12 18:06 ` Junio C Hamano
2020-08-11 22:52 ` [PATCH v2 5/7] fetch-pack: do not lazy-fetch during ref iteration Jonathan Tan
2020-08-12 18:25 ` Junio C Hamano
2020-08-11 22:52 ` [PATCH v2 6/7] promisor-remote: lazy-fetch objects in subprocess Jonathan Tan
2020-08-12 18:28 ` Junio C Hamano
2020-08-11 22:52 ` [PATCH v2 7/7] fetch-pack: remove no_dependents code Jonathan Tan
2020-08-12 12:51 ` [PATCH v2 0/7] Lazy fetch with subprocess Derrick Stolee
2020-08-18 4:01 ` [PATCH v3 " Jonathan Tan
2020-08-18 4:01 ` [PATCH v3 1/7] negotiator/noop: add noop fetch negotiator Jonathan Tan
2020-08-18 4:01 ` [PATCH v3 2/7] fetch: allow refspecs specified through stdin Jonathan Tan
2020-08-18 4:01 ` [PATCH v3 3/7] fetch: avoid reading submodule config until needed Jonathan Tan
2020-08-18 4:01 ` [PATCH v3 4/7] fetch: only populate existing_refs if needed Jonathan Tan
2020-08-18 4:01 ` [PATCH v3 5/7] fetch-pack: do not lazy-fetch during ref iteration Jonathan Tan
2020-08-18 4:01 ` [PATCH v3 6/7] promisor-remote: lazy-fetch objects in subprocess Jonathan Tan
2020-08-18 4:01 ` [PATCH v3 7/7] fetch-pack: remove no_dependents code Jonathan Tan
2020-08-18 19:56 ` [PATCH v3 0/7] Lazy fetch with subprocess Junio C Hamano
2020-08-18 22:32 ` Junio C Hamano
2020-08-18 23:36 ` [PATCH] fixup! promisor-remote: lazy-fetch objects in subprocess Jonathan Tan
2020-08-18 23:57 ` Junio C Hamano
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
List information: http://vger.kernel.org/majordomo-info.html
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=35bdd372ae3691f54775dd616576e8ed6d68f1d3.1597184949.git.jonathantanmy@google.com \
--to=jonathantanmy@google.com \
--cc=git@vger.kernel.org \
--cc=gitster@pobox.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://80x24.org/mirrors/git.git
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).