From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.5 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI shortcircuit=no autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 76FBF1F62D for ; Fri, 6 Jul 2018 00:53:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753870AbeGFAxm (ORCPT ); Thu, 5 Jul 2018 20:53:42 -0400 Received: from mail-qt0-f193.google.com ([209.85.216.193]:42719 "EHLO mail-qt0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753442AbeGFAxh (ORCPT ); Thu, 5 Jul 2018 20:53:37 -0400 Received: by mail-qt0-f193.google.com with SMTP id z8-v6so204266qto.9 for ; Thu, 05 Jul 2018 17:53:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=y5lvIM3ZzsPuv5mkG0vespzDPZRmc8rqdnB2xDQSYQw=; b=GXZH5WtrOfR4qDS9Ri1mecHTNH0vx83nkBnwLieRl+Gr5mEnlD4KsO9DVgd+CEjJus a872h7tb92W2DQSoQHIyZnyliA/gf4P5FTmr4+E67ZXMqFMbKWYskGFgaas66PKLaida T5+OylkSwhmFayDSbMEFGQa4OUMV23gvaHeksbxihJdhuLLX+Str7lFGdRDbRyo7xnTc Z2AYEuiCevbQYhPYkUuIufnTDUtWGG9tWruASgSUI4TCSVRmtDwKnYujCX2XrFHYldb0 bNVdFTetbEZjIOPOKKANIHAPzDZKqvH27+2K/BaFuHHauTj4nlqwMK94G364LbNTtuXk ejUw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=y5lvIM3ZzsPuv5mkG0vespzDPZRmc8rqdnB2xDQSYQw=; b=qS1dzjzSP5r0YRUZfqG8OMPmpCyjCFlia0AQ2jUAe7ixkxCFYpqPR0muh1S/sDDK1W wqk5cusBGc2o1iO2Z+XBMYoUdnRNBGuMt+MNwdDflfBXdBQ9KbqSM5yY34EyYbUgG5qT PWOsNVeUWCJwKe9DplxTkSlxQPCDCwPHUkelFcO5DzPoeNUCzvZnNDGVxtoIjvl0onb8 5RuNJ/NOdcVscDQhkCrBWvd+O0OxSHeubv/0rScURekw+mPmztWU6jrlCRmlNs9g3Hwf QZsQ72IqJanZnonVPiQUkwm9tR2DjhiHvlgZ88XNw7eIlfJhH26RbGV5tLo3qNwcD5fV Df7g== X-Gm-Message-State: APt69E0GMhsuFBbWnh6HMl5MQFtnOeqJoKKk9582ADtOV+KZpWmTgzbT A0XHDQiCzyP9utsZbC3h02M2QPCx X-Google-Smtp-Source: AAOMgpcThmYHyacsCYVlNoS4RdluX7EuWGJuVroO1DHu8wWsbZwEfQclWIfi6DtBT/Zxgymhmz/Lww== X-Received: by 2002:aed:3cc3:: with SMTP id e3-v6mr7551048qtf.356.1530838416129; Thu, 05 Jul 2018 17:53:36 -0700 (PDT) Received: from stolee-linux-2.corp.microsoft.com ([2001:4898:8010:0:eb4a:5dff:fe0f:730f]) by smtp.gmail.com with ESMTPSA id u25-v6sm4882791qku.3.2018.07.05.17.53.35 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 05 Jul 2018 17:53:35 -0700 (PDT) From: Derrick Stolee X-Google-Original-From: Derrick Stolee To: git@vger.kernel.org Cc: gitster@pobox.com, sbeller@google.com, pclouds@gmail.com, avarab@gmail.com, dstolee@microsoft.com Subject: [PATCH v3 05/24] midx: write header information to lockfile Date: Thu, 5 Jul 2018 20:53:02 -0400 Message-Id: <20180706005321.124643-6-dstolee@microsoft.com> X-Mailer: git-send-email 2.18.0.118.gd4f65b8d14 In-Reply-To: <20180706005321.124643-1-dstolee@microsoft.com> References: <20180625143434.89044-1-dstolee@microsoft.com> <20180706005321.124643-1-dstolee@microsoft.com> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org As we begin writing the multi-pack-index format to disk, start with the basics: the 12-byte header and the 20-byte checksum footer. Start with these basics so we can add the rest of the format in small increments. As we implement the format, we will use a technique to check that our computed offsets within the multi-pack-index file match what we are actually writing. Each method that writes to the hashfile will return the number of bytes written, and we will track that those values match our expectations. Currently, write_midx_header() returns 12, but is not checked. We will check the return value in a later commit. Signed-off-by: Derrick Stolee --- midx.c | 50 +++++++++++++++++++++++++++++++++++++ t/t5319-multi-pack-index.sh | 3 ++- 2 files changed, 52 insertions(+), 1 deletion(-) diff --git a/midx.c b/midx.c index 32468db1a2..f85f2d334d 100644 --- a/midx.c +++ b/midx.c @@ -1,7 +1,57 @@ #include "cache.h" +#include "csum-file.h" +#include "lockfile.h" #include "midx.h" +#define MIDX_SIGNATURE 0x4d494458 /* "MIDX" */ +#define MIDX_VERSION 1 +#define MIDX_HASH_VERSION 1 +#define MIDX_HEADER_SIZE 12 + +static char *get_midx_filename(const char *object_dir) +{ + return xstrfmt("%s/pack/multi-pack-index", object_dir); +} + +static size_t write_midx_header(struct hashfile *f, + unsigned char num_chunks, + uint32_t num_packs) +{ + unsigned char byte_values[4]; + + hashwrite_be32(f, MIDX_SIGNATURE); + byte_values[0] = MIDX_VERSION; + byte_values[1] = MIDX_HASH_VERSION; + byte_values[2] = num_chunks; + byte_values[3] = 0; /* unused */ + hashwrite(f, byte_values, sizeof(byte_values)); + hashwrite_be32(f, num_packs); + + return MIDX_HEADER_SIZE; +} + int write_midx_file(const char *object_dir) { + unsigned char num_chunks = 0; + char *midx_name; + struct hashfile *f = NULL; + struct lock_file lk; + + midx_name = get_midx_filename(object_dir); + if (safe_create_leading_directories(midx_name)) { + UNLEAK(midx_name); + die_errno(_("unable to create leading directories of %s"), + midx_name); + } + + hold_lock_file_for_update(&lk, midx_name, LOCK_DIE_ON_ERROR); + f = hashfd(lk.tempfile->fd, lk.tempfile->filename.buf); + FREE_AND_NULL(midx_name); + + write_midx_header(f, num_chunks, 0); + + finalize_hashfile(f, NULL, CSUM_FSYNC | CSUM_HASH_IN_STREAM); + commit_lock_file(&lk); + return 0; } diff --git a/t/t5319-multi-pack-index.sh b/t/t5319-multi-pack-index.sh index ec3ddbe79c..8622a7cdce 100755 --- a/t/t5319-multi-pack-index.sh +++ b/t/t5319-multi-pack-index.sh @@ -4,7 +4,8 @@ test_description='multi-pack-indexes' . ./test-lib.sh test_expect_success 'write midx with no packs' ' - git multi-pack-index --object-dir=. write + git multi-pack-index --object-dir=. write && + test_path_is_file pack/multi-pack-index ' test_done -- 2.18.0.118.gd4f65b8d14