From patchwork Tue Aug 11 22:52:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jonathan Tan X-Patchwork-Id: 11709775 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 95AD4159A for ; Tue, 11 Aug 2020 22:52:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 77A6920782 for ; Tue, 11 Aug 2020 22:52:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="JK5DU3Dh" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726453AbgHKWwb (ORCPT ); Tue, 11 Aug 2020 18:52:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43806 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726023AbgHKWwb (ORCPT ); Tue, 11 Aug 2020 18:52:31 -0400 Received: from mail-pj1-x104a.google.com (mail-pj1-x104a.google.com [IPv6:2607:f8b0:4864:20::104a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 00F3EC06174A for ; Tue, 11 Aug 2020 15:52:31 -0700 (PDT) Received: by mail-pj1-x104a.google.com with SMTP id a6so317335pjd.1 for ; Tue, 11 Aug 2020 15:52:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=bfnczTnXw8CEsvNQ+zFRvEgwXldfKc0Uajp2AQ2rAfg=; b=JK5DU3Dh26NHRxPEl1I7eUTC8jCJl+6smuVuUe9abriHzWsiFVDmrrOa4erqLQd/Py PYX8JxHcIzv9AKn5ESHBtk/l5WH1B0gnQ9VA7Fgs8tjY/ZCNdV9aLIvDqf8X8STBmiyK 7eS8Piw5ir4c1aVG3PTEnWVOLblYhlEa2F7yOJVG9ylYb3Ne8TiQE+G7oe4SkCr9B0la wS2MlWVcRv+2/yZ1gyVKtLqduhVOO6wUq2mWnxR+y06ISvXjL76uqn5eGPMcUUj9GSBT G6+Xnjim/TLADivBlpap7tOvrjJmNGV54nJmBt/qF2wHWAQoZ7ZrSZCViLB3/BSrmzrt KNYA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=bfnczTnXw8CEsvNQ+zFRvEgwXldfKc0Uajp2AQ2rAfg=; b=ZhNf/XziBbTuGyHkn5mjkiu0UK9qmXm9bgG/Nn9ofOCF8W1agHzKjenqpnjwUO3RqC CeJ70eqa+MUKnFv4ZO1+EJtUnk6E4UBsuVld6jtE9Q9Mi+LimYE6Gx7GxMswVRz4agEz RDM1UUzCaOfk3e6or+kBs66PkOLLPymMf/kXRVpbrNpZ+SkSZ8FfDw/9UF/qUNG7u6re tuFuUT/NYZM/He6zN0R/fm25JTE78ztn3ijgvRmZj3h+lVE3pXEawli8ai1o4pnbIthR JrPDFOS3+bFhOEsZTkJS2WdAdRHFI2pFz3Nuv3+QqEFWYPesV9WoRWfjNSYxDjRVmsvx 2XTw== X-Gm-Message-State: AOAM531GBcHKVCseVQLkHMcklzSilssBmTRdDwjWYjUQ2RZQ2ZMsTR0e hN0OcN+TJ9qwLJfVwCqEeZGewFGJ82Sfe72/9g+GLezxyz2xCAl4YLQoeUQZGbLR6bEGtZ99fhI zpvOlNpXaHq0RWPnThSMK9+y+dsDKWSAoQVb1vY5JEuknExo6Gy0mv/1p1yUxHuu78rHYj6pmzj Jr X-Google-Smtp-Source: ABdhPJxp1wakPQk7SUBK0wS0HekcSCxybSkae5csFTjmdajs12h5wQi2RoPCzYRZ9eXsqqHqx+8JVVJ4zunnF93EkiO9 X-Received: by 2002:a17:90a:f2c7:: with SMTP id gt7mr3066130pjb.204.1597186349952; Tue, 11 Aug 2020 15:52:29 -0700 (PDT) Date: Tue, 11 Aug 2020 15:52:16 -0700 In-Reply-To: Message-Id: <35bdd372ae3691f54775dd616576e8ed6d68f1d3.1597184949.git.jonathantanmy@google.com> Mime-Version: 1.0 References: <20200724223844.2723397-1-jonathantanmy@google.com> X-Mailer: git-send-email 2.28.0.236.gb10cc79966-goog Subject: [PATCH v2 1/7] negotiator/null: add null fetch negotiator From: Jonathan Tan To: git@vger.kernel.org Cc: Jonathan Tan , gitster@pobox.com Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org 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 --- 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