From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-Status: No, score=-3.8 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, SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by dcvr.yhbt.net (Postfix) with ESMTP id 015B51F9FD for ; Thu, 18 Feb 2021 16:51:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232929AbhBRQq1 (ORCPT ); Thu, 18 Feb 2021 11:46:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41424 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233550AbhBROI3 (ORCPT ); Thu, 18 Feb 2021 09:08:29 -0500 Received: from mail-wm1-x32f.google.com (mail-wm1-x32f.google.com [IPv6:2a00:1450:4864:20::32f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F3349C061788 for ; Thu, 18 Feb 2021 06:07:44 -0800 (PST) Received: by mail-wm1-x32f.google.com with SMTP id o10so2856282wmc.1 for ; Thu, 18 Feb 2021 06:07:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=message-id:in-reply-to:references:from:date:subject:fcc :content-transfer-encoding:mime-version:to:cc; bh=eVXJhiJktjVMhH9E9QDbeeZ0spv2V4GDVPN9nLs5T2c=; b=uXal/FHBlp1xXfV70FZV9A/d/dmbSEvrTQa/JjOsZgcb1S+6//Cd+vcr7VeOmotzCt DVwkrutOyP6VNvLXPazVw/KNwmxUr8Kzj+AXUTFyul/IOlX2Dwi3Nb3Z+kwY8dhKq6Qp 5Q5StIWhpOzEQOEo8lTubnyHd4WIKebJX78De8qhPMDOZ8iUUIbNdYd5AcYIOKoAiN3X Q3u+rpnHoUAMaUcalXtYDBhC6OL695wuEJfd68RKVHWhssvMhQ7egPImXb5P7FqcYrjs uOCnrw/5EHaz5FA4V1lyBDTVYIvK+zdVEpQ70ECqnFBMFh5ADr3cdVFDsWecDJ4SmeMz 5dmQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:in-reply-to:references:from:date :subject:fcc:content-transfer-encoding:mime-version:to:cc; bh=eVXJhiJktjVMhH9E9QDbeeZ0spv2V4GDVPN9nLs5T2c=; b=VxILc0MhfnnKQlBWPNypB2rXlBHmSlT9B3Nmoxvyrht+kkUxeA2EBg+SfmODp1uG7H Hjaycf9Mkh+IVrP9h798Ii/dFWliT7uq7rvY3bwR0t53hGXHYjPwvUVVfkkvHxyTnZot dIxXjqx4TQqhu5bAydKekR1EdJyorOhoehzRR6Wda1bI8XJIPzyY0bXnHvyYBe1+8U1O TRa3nx7PiFpFmuFZsuSNfdLTsSwJR64b7isLSjQKOwVQ24pivDxifnwFO+VSI/SskqFQ VHQ/I8F6QUC9Ps36PtT4fVD4nN4tpKs+O5NJchJGrNDdDJXwQJhMWd5ydM7DH+gWm7kT uweg== X-Gm-Message-State: AOAM533TjKv3NSCsm4LQCg/dYoU/xrYmCJFYc9G1g60w6488kRi026Ui rPf1Za76DlSQMDZ1UXeL6cnlIZFe2tg= X-Google-Smtp-Source: ABdhPJyP5cEQZKT+JFXMGerqG5r86GnGFhUEmbA1rkQK/Vs2tcvhQyfzDoKY6wioYFM4YK3cYk9DXQ== X-Received: by 2002:a7b:ce12:: with SMTP id m18mr3881999wmc.148.1613657263708; Thu, 18 Feb 2021 06:07:43 -0800 (PST) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id r17sm9395146wrx.82.2021.02.18.06.07.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 Feb 2021 06:07:43 -0800 (PST) Message-Id: In-Reply-To: References: From: "Derrick Stolee via GitGitGadget" Date: Thu, 18 Feb 2021 14:07:24 +0000 Subject: [PATCH v4 02/17] chunk-format: create chunk format write API Fcc: Sent Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit MIME-Version: 1.0 To: git@vger.kernel.org Cc: me@ttaylorr.com, gitster@pobox.com, l.s.r@web.de, szeder.dev@gmail.com, Chris Torek , Derrick Stolee , Derrick Stolee , Derrick Stolee Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Derrick Stolee In anticipation of combining the logic from the commit-graph and multi-pack-index file formats, create a new chunk-format API. Use a 'struct chunkfile' pointer to keep track of data that has been registered for writes. This struct is anonymous outside of chunk-format.c to ensure no user attempts to interfere with the data. The next change will use this API in commit-graph.c, but the general approach is: 1. initialize the chunkfile with init_chunkfile(f). 2. add chunks in the intended writing order with add_chunk(). 3. write any header information to the hashfile f. 4. write the chunkfile data using write_chunkfile(). 5. free the chunkfile struct using free_chunkfile(). Helped-by: Taylor Blau Helped-by: Junio C Hamano Signed-off-by: Derrick Stolee --- Makefile | 1 + chunk-format.c | 90 ++++++++++++++++++++++++++++++++++++++++++++++++++ chunk-format.h | 21 ++++++++++++ 3 files changed, 112 insertions(+) create mode 100644 chunk-format.c create mode 100644 chunk-format.h diff --git a/Makefile b/Makefile index 7b64106930a6..50a7663841e9 100644 --- a/Makefile +++ b/Makefile @@ -854,6 +854,7 @@ LIB_OBJS += bundle.o LIB_OBJS += cache-tree.o LIB_OBJS += chdir-notify.o LIB_OBJS += checkout.o +LIB_OBJS += chunk-format.o LIB_OBJS += color.o LIB_OBJS += column.o LIB_OBJS += combine-diff.o diff --git a/chunk-format.c b/chunk-format.c new file mode 100644 index 000000000000..6c9b52b70c10 --- /dev/null +++ b/chunk-format.c @@ -0,0 +1,90 @@ +#include "cache.h" +#include "chunk-format.h" +#include "csum-file.h" + +/* + * When writing a chunk-based file format, collect the chunks in + * an array of chunk_info structs. The size stores the _expected_ + * amount of data that will be written by write_fn. + */ +struct chunk_info { + uint32_t id; + uint64_t size; + chunk_write_fn write_fn; +}; + +struct chunkfile { + struct hashfile *f; + + struct chunk_info *chunks; + size_t chunks_nr; + size_t chunks_alloc; +}; + +struct chunkfile *init_chunkfile(struct hashfile *f) +{ + struct chunkfile *cf = xcalloc(1, sizeof(*cf)); + cf->f = f; + return cf; +} + +void free_chunkfile(struct chunkfile *cf) +{ + if (!cf) + return; + free(cf->chunks); + free(cf); +} + +int get_num_chunks(struct chunkfile *cf) +{ + return cf->chunks_nr; +} + +void add_chunk(struct chunkfile *cf, + uint32_t id, + size_t size, + chunk_write_fn fn) +{ + ALLOC_GROW(cf->chunks, cf->chunks_nr + 1, cf->chunks_alloc); + + cf->chunks[cf->chunks_nr].id = id; + cf->chunks[cf->chunks_nr].write_fn = fn; + cf->chunks[cf->chunks_nr].size = size; + cf->chunks_nr++; +} + +int write_chunkfile(struct chunkfile *cf, void *data) +{ + int i; + uint64_t cur_offset = hashfile_total(cf->f); + + /* Add the table of contents to the current offset */ + cur_offset += (cf->chunks_nr + 1) * CHUNK_TOC_ENTRY_SIZE; + + for (i = 0; i < cf->chunks_nr; i++) { + hashwrite_be32(cf->f, cf->chunks[i].id); + hashwrite_be64(cf->f, cur_offset); + + cur_offset += cf->chunks[i].size; + } + + /* Trailing entry marks the end of the chunks */ + hashwrite_be32(cf->f, 0); + hashwrite_be64(cf->f, cur_offset); + + for (i = 0; i < cf->chunks_nr; i++) { + off_t start_offset = hashfile_total(cf->f); + int result = cf->chunks[i].write_fn(cf->f, data); + + if (result) + return result; + + if (hashfile_total(cf->f) - start_offset != cf->chunks[i].size) + BUG("expected to write %"PRId64" bytes to chunk %"PRIx32", but wrote %"PRId64" instead", + cf->chunks[i].size, cf->chunks[i].id, + hashfile_total(cf->f) - start_offset); + } + + return 0; +} diff --git a/chunk-format.h b/chunk-format.h new file mode 100644 index 000000000000..ce598b66d9f8 --- /dev/null +++ b/chunk-format.h @@ -0,0 +1,21 @@ +#ifndef CHUNK_FORMAT_H +#define CHUNK_FORMAT_H + +#include "git-compat-util.h" + +struct hashfile; +struct chunkfile; + +#define CHUNK_TOC_ENTRY_SIZE (sizeof(uint32_t) + sizeof(uint64_t)) + +struct chunkfile *init_chunkfile(struct hashfile *f); +void free_chunkfile(struct chunkfile *cf); +int get_num_chunks(struct chunkfile *cf); +typedef int (*chunk_write_fn)(struct hashfile *f, void *data); +void add_chunk(struct chunkfile *cf, + uint32_t id, + size_t size, + chunk_write_fn fn); +int write_chunkfile(struct chunkfile *cf, void *data); + +#endif -- gitgitgadget