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-ASN: AS3215 2.6.0.0/16 X-Spam-Status: No, score=-3.6 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_NONE,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from out1.vger.email (out1.vger.email [IPv6:2620:137:e000::1:20]) by dcvr.yhbt.net (Postfix) with ESMTP id B48A11F403 for ; Tue, 4 Oct 2022 12:34:59 +0000 (UTC) Authentication-Results: dcvr.yhbt.net; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="gQqnTAQ2"; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229799AbiJDMe5 (ORCPT ); Tue, 4 Oct 2022 08:34:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46334 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229826AbiJDMel (ORCPT ); Tue, 4 Oct 2022 08:34:41 -0400 Received: from mail-wm1-x32b.google.com (mail-wm1-x32b.google.com [IPv6:2a00:1450:4864:20::32b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E940D22B for ; Tue, 4 Oct 2022 05:34:34 -0700 (PDT) Received: by mail-wm1-x32b.google.com with SMTP id v130-20020a1cac88000000b003bcde03bd44so97713wme.5 for ; Tue, 04 Oct 2022 05:34:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=cc:to:mime-version:content-transfer-encoding:fcc:subject:date:from :references:in-reply-to:message-id:from:to:cc:subject:date; bh=eIoFf1sG9BaLf+yAuIeR43J9VX1V0Yz61/CFU78LiBI=; b=gQqnTAQ2ZJenRlYO/XCKeoUkO04lmOIrcA6YLwnSa35E+0uTMvEtmDZnKApHITaTU6 Mvx/X/DOHCeLEFZ/MRP/BtG55kacaAVzjQhr46KiEgo0aWvFobDllu/6EK3mtMprOcmq dPq1/EBjuVFwaGyoJHh4zg7uhV2La9HM7OAy4DowvxY/0vCGe7WP+PwOQTKl9FzTlkXJ sc/XCUlwu13/02lx8yhxXgmE04C5rMlAYu3z51GBDoueCrkgFVYiN8clmovYLb+cH/QN 9Es39CG9lqh3/79w2pZun5fJl2WmJKA+Oxb/kkvb1qKgbAfKbTitGzWZmHwoyrw0pvg1 itqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:mime-version:content-transfer-encoding:fcc:subject:date:from :references:in-reply-to:message-id:x-gm-message-state:from:to:cc :subject:date; bh=eIoFf1sG9BaLf+yAuIeR43J9VX1V0Yz61/CFU78LiBI=; b=xwCTnJWMIAYyEhmiV0oXUz+g6DBFwvXXjL7mq1e6ysGkg+hBp1LqpW/2s4QFaMwHkF sHzBEDygZ8iFRO7ooJygYPyJhlpC0z331LaJAan2XDyHEvgwBGIwI6t0m8LVk2JXU9s1 aKyj0/IvPHZagaVFALbm7ls8sAlLXm4Mq7ddxuy9qvs8Qsk/VmmGJw8kS+q9eEHQ2jgE S06XsLTjP2PGt6NSwKyl0+yE21wLHico7hfVsGlY3CH1q5Zf/Mohir7le4LVwQyn0d5r 9YSiGb1zByTG3yVc3OGSi9LH1k8+4y3fJyYu93Ops+kw0FMBP47hd4JZ2vP8F12n9V63 5EJw== X-Gm-Message-State: ACrzQf10bH/z6M72Tw7hKflOgH3kMOqMD+Ry83QF/+0u3Yv1QpgnaxON RG++O+do2+c5JOTEnPbxePOVoWOi18E= X-Google-Smtp-Source: AMsMyM5v3m13CQU40+yhuL3c8DPaGRQVDXjDSZD53yxNTVWcjtZnpzBXcSxbg3cG9yRdTwOfgyVpqA== X-Received: by 2002:a05:600c:1d25:b0:3b4:92de:fb28 with SMTP id l37-20020a05600c1d2500b003b492defb28mr10263024wms.202.1664886872168; Tue, 04 Oct 2022 05:34:32 -0700 (PDT) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id m10-20020adfe0ca000000b0022e36c1113fsm6693488wri.13.2022.10.04.05.34.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 04 Oct 2022 05:34:31 -0700 (PDT) Message-Id: <46799648b4ce16b0cbacc307443a343994ed064f.1664886861.git.gitgitgadget@gmail.com> In-Reply-To: References: From: "Derrick Stolee via GitGitGadget" Date: Tue, 04 Oct 2022 12:34:19 +0000 Subject: [PATCH v3 8/9] bundle-uri: fetch a list of bundles Fcc: Sent Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit MIME-Version: 1.0 To: git@vger.kernel.org Cc: gitster@pobox.com, me@ttaylorr.com, newren@gmail.com, avarab@gmail.com, mjcheetham@outlook.com, steadmon@google.com, Glen Choo , Jonathan Tan , Teng Long , Derrick Stolee , Derrick Stolee Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Derrick Stolee When the content at a given bundle URI is not understood as a bundle (based on inspecting the initial content), then Git currently gives up and ignores that content. Independent bundle providers may want to split up the bundle content into multiple bundles, but still make them available from a single URI. Teach Git to attempt parsing the bundle URI content as a Git config file providing the key=value pairs for a bundle list. Git then looks at the mode of the list to see if ANY single bundle is sufficient or if ALL bundles are required. The content at the selected URIs are downloaded and the content is inspected again, creating a recursive process. To guard the recursion against malformed or malicious content, limit the recursion depth to a reasonable four for now. This can be converted to a configured value in the future if necessary. The value of four is twice as high as expected to be useful (a bundle list is unlikely to point to more bundle lists). To test this scenario, create an interesting bundle topology where three incremental bundles are built on top of a single full bundle. By using a merge commit, the two middle bundles are "independent" in that they do not require each other in order to unbundle themselves. They each only need the base bundle. The bundle containing the merge commit requires both of the middle bundles, though. This leads to some interesting decisions when unbundling, especially when we later implement heuristics that promote downloading bundles until the prerequisite commits are satisfied. Signed-off-by: Derrick Stolee --- bundle-uri.c | 202 +++++++++++++++++++++++++++++++++--- bundle-uri.h | 13 +++ t/t5558-clone-bundle-uri.sh | 135 ++++++++++++++++++++++++ 3 files changed, 334 insertions(+), 16 deletions(-) diff --git a/bundle-uri.c b/bundle-uri.c index 8a7c11c6393..aaa1848044a 100644 --- a/bundle-uri.c +++ b/bundle-uri.c @@ -37,6 +37,8 @@ static int clear_remote_bundle_info(struct remote_bundle_info *bundle, { FREE_AND_NULL(bundle->id); FREE_AND_NULL(bundle->uri); + FREE_AND_NULL(bundle->file); + bundle->unbundled = 0; return 0; } @@ -334,18 +336,116 @@ static int unbundle_from_file(struct repository *r, const char *file) return result; } +struct bundle_list_context { + struct repository *r; + struct bundle_list *list; + enum bundle_list_mode mode; + int count; + int depth; +}; + +/* + * This early definition is necessary because we use indirect recursion: + * + * While iterating through a bundle list that was downloaded as part + * of fetch_bundle_uri_internal(), iterator methods eventually call it + * again, but with depth + 1. + */ +static int fetch_bundle_uri_internal(struct repository *r, + struct remote_bundle_info *bundle, + int depth, + struct bundle_list *list); + +static int download_bundle_to_file(struct remote_bundle_info *bundle, void *data) +{ + int res; + struct bundle_list_context *ctx = data; + + if (ctx->mode == BUNDLE_MODE_ANY && ctx->count) + return 0; + + res = fetch_bundle_uri_internal(ctx->r, bundle, ctx->depth + 1, ctx->list); + + /* + * Only increment count if the download succeeded. If our mode is + * BUNDLE_MODE_ANY, then we will want to try other URIs in the + * list in case they work instead. + */ + if (!res) + ctx->count++; + + /* + * In BUNDLE_MODE_ANY, we need to continue iterating until we find + * a bundle that works, so do not signal a failure here. + */ + return ctx->mode == BUNDLE_MODE_ANY ? 0 : res; +} + +static int download_bundle_list(struct repository *r, + struct bundle_list *local_list, + struct bundle_list *global_list, + int depth) +{ + struct bundle_list_context ctx = { + .r = r, + .list = global_list, + .depth = depth + 1, + .mode = local_list->mode, + }; + + return for_all_bundles_in_list(local_list, download_bundle_to_file, &ctx); +} + +static int fetch_bundle_list_in_config_format(struct repository *r, + struct bundle_list *global_list, + struct remote_bundle_info *bundle, + int depth) +{ + int result; + struct bundle_list list_from_bundle; + + init_bundle_list(&list_from_bundle); + + if ((result = bundle_uri_parse_config_format(bundle->uri, + bundle->file, + &list_from_bundle))) + goto cleanup; + + if (list_from_bundle.mode == BUNDLE_MODE_NONE) { + warning(_("unrecognized bundle mode from URI '%s'"), + bundle->uri); + result = -1; + goto cleanup; + } + + if ((result = download_bundle_list(r, &list_from_bundle, + global_list, depth))) + goto cleanup; + +cleanup: + clear_bundle_list(&list_from_bundle); + return result; +} + /** * This limits the recursion on fetch_bundle_uri_internal() when following * bundle lists. */ static int max_bundle_uri_depth = 4; +/** + * Recursively download all bundles advertised at the given URI + * to files. If the file is a bundle, then add it to the given + * 'list'. Otherwise, expect a bundle list and recurse on the + * URIs in that list according to the list mode (ANY or ALL). + */ static int fetch_bundle_uri_internal(struct repository *r, - const char *uri, - int depth) + struct remote_bundle_info *bundle, + int depth, + struct bundle_list *list) { int result = 0; - char *filename; + struct remote_bundle_info *bcopy; if (depth >= max_bundle_uri_depth) { warning(_("exceeded bundle URI recursion limit (%d)"), @@ -353,36 +453,106 @@ static int fetch_bundle_uri_internal(struct repository *r, return -1; } - if (!(filename = find_temp_filename())) { + if (!bundle->file && + !(bundle->file = find_temp_filename())) { result = -1; goto cleanup; } - if ((result = copy_uri_to_file(filename, uri))) { - warning(_("failed to download bundle from URI '%s'"), uri); + if ((result = copy_uri_to_file(bundle->file, bundle->uri))) { + warning(_("failed to download bundle from URI '%s'"), bundle->uri); goto cleanup; } - if ((result = !is_bundle(filename, 0))) { - warning(_("file at URI '%s' is not a bundle"), uri); + if ((result = !is_bundle(bundle->file, 1))) { + result = fetch_bundle_list_in_config_format( + r, list, bundle, depth); + if (result) + warning(_("file at URI '%s' is not a bundle or bundle list"), + bundle->uri); goto cleanup; } - if ((result = unbundle_from_file(r, filename))) { - warning(_("failed to unbundle bundle from URI '%s'"), uri); - goto cleanup; - } + /* Copy the bundle and insert it into the global list. */ + CALLOC_ARRAY(bcopy, 1); + bcopy->id = xstrdup(bundle->id); + bcopy->file = xstrdup(bundle->file); + hashmap_entry_init(&bcopy->ent, strhash(bcopy->id)); + hashmap_add(&list->bundles, &bcopy->ent); cleanup: - if (filename) - unlink(filename); - free(filename); + if (result && bundle->file) + unlink(bundle->file); return result; } +/** + * This loop iterator breaks the loop with nonzero return code on the + * first successful unbundling of a bundle. + */ +static int attempt_unbundle(struct remote_bundle_info *info, void *data) +{ + struct repository *r = data; + + if (!info->file || info->unbundled) + return 0; + + if (!unbundle_from_file(r, info->file)) { + info->unbundled = 1; + return 1; + } + + return 0; +} + +static int unbundle_all_bundles(struct repository *r, + struct bundle_list *list) +{ + /* + * Iterate through all bundles looking for ones that can + * successfully unbundle. If any succeed, then perhaps another + * will succeed in the next attempt. + * + * Keep in mind that a non-zero result for the loop here means + * the loop terminated early on a successful unbundling, which + * signals that we can try again. + */ + while (for_all_bundles_in_list(list, attempt_unbundle, r)) ; + + return 0; +} + +static int unlink_bundle(struct remote_bundle_info *info, void *data) +{ + if (info->file) + unlink_or_warn(info->file); + return 0; +} + int fetch_bundle_uri(struct repository *r, const char *uri) { - return fetch_bundle_uri_internal(r, uri, 0); + int result; + struct bundle_list list; + struct remote_bundle_info bundle = { + .uri = xstrdup(uri), + .id = xstrdup(""), + }; + + init_bundle_list(&list); + + /* If a bundle is added to this global list, then it is required. */ + list.mode = BUNDLE_MODE_ALL; + + if ((result = fetch_bundle_uri_internal(r, &bundle, 0, &list))) + goto cleanup; + + result = unbundle_all_bundles(r, &list); + +cleanup: + for_all_bundles_in_list(&list, unlink_bundle, NULL); + clear_bundle_list(&list); + clear_remote_bundle_info(&bundle, NULL); + return result; } /** diff --git a/bundle-uri.h b/bundle-uri.h index bc13d4c9929..4dbc269823c 100644 --- a/bundle-uri.h +++ b/bundle-uri.h @@ -28,6 +28,19 @@ struct remote_bundle_info { * if there was no table of contents. */ char *uri; + + /** + * If the bundle has been downloaded, then 'file' is a + * filename storing its contents. Otherwise, 'file' is + * NULL. + */ + char *file; + + /** + * If the bundle has been unbundled successfully, then + * this boolean is true. + */ + unsigned unbundled:1; }; #define REMOTE_BUNDLE_INFO_INIT { 0 } diff --git a/t/t5558-clone-bundle-uri.sh b/t/t5558-clone-bundle-uri.sh index ad666a2d28a..9690f19386f 100755 --- a/t/t5558-clone-bundle-uri.sh +++ b/t/t5558-clone-bundle-uri.sh @@ -41,6 +41,92 @@ test_expect_success 'clone with file:// bundle' ' test_cmp expect actual ' +# To get interesting tests for bundle lists, we need to construct a +# somewhat-interesting commit history. +# +# ---------------- bundle-4 +# +# 4 +# / \ +# ----|---|------- bundle-3 +# | | +# | 3 +# | | +# ----|---|------- bundle-2 +# | | +# 2 | +# | | +# ----|---|------- bundle-1 +# \ / +# 1 +# | +# (previous commits) +test_expect_success 'construct incremental bundle list' ' + ( + cd clone-from && + git checkout -b base && + test_commit 1 && + git checkout -b left && + test_commit 2 && + git checkout -b right base && + test_commit 3 && + git checkout -b merge left && + git merge right -m "4" && + + git bundle create bundle-1.bundle base && + git bundle create bundle-2.bundle base..left && + git bundle create bundle-3.bundle base..right && + git bundle create bundle-4.bundle merge --not left right + ) +' + +test_expect_success 'clone bundle list (file, no heuristic)' ' + cat >bundle-list <<-EOF && + [bundle] + version = 1 + mode = all + + [bundle "bundle-1"] + uri = file://$(pwd)/clone-from/bundle-1.bundle + + [bundle "bundle-2"] + uri = file://$(pwd)/clone-from/bundle-2.bundle + + [bundle "bundle-3"] + uri = file://$(pwd)/clone-from/bundle-3.bundle + + [bundle "bundle-4"] + uri = file://$(pwd)/clone-from/bundle-4.bundle + EOF + + git clone --bundle-uri="file://$(pwd)/bundle-list" clone-from clone-list-file && + git -C clone-from for-each-ref --format="%(objectname)" >oids && + git -C clone-list-file cat-file --batch-check bundle-list <<-EOF && + [bundle] + version = 1 + mode = any + + # Does not exist. Should be skipped. + [bundle "bundle-0"] + uri = $HTTPD_URL/bundle-0.bundle + + [bundle "bundle-1"] + uri = $HTTPD_URL/bundle-1.bundle + + # Does not exist. Should be skipped. + [bundle "bundle-5"] + uri = $HTTPD_URL/bundle-5.bundle + EOF + + git clone --bundle-uri="file://$(pwd)/bundle-list" clone-from clone-any-file && + git -C clone-from for-each-ref --format="%(objectname)" >oids && + git -C clone-any-file cat-file --batch-check "$HTTPD_DOCUMENT_ROOT_PATH/bundle-list" <<-EOF && + [bundle] + version = 1 + mode = all + + [bundle "bundle-1"] + uri = $HTTPD_URL/bundle-1.bundle + + [bundle "bundle-2"] + uri = $HTTPD_URL/bundle-2.bundle + + [bundle "bundle-3"] + uri = $HTTPD_URL/bundle-3.bundle + + [bundle "bundle-4"] + uri = $HTTPD_URL/bundle-4.bundle + EOF + + git clone --bundle-uri="$HTTPD_URL/bundle-list" clone-from clone-list-http && + git -C clone-from for-each-ref --format="%(objectname)" >oids && + git -C clone-list-http cat-file --batch-check "$HTTPD_DOCUMENT_ROOT_PATH/bundle-list" <<-EOF && + [bundle] + version = 1 + mode = any + + # Does not exist. Should be skipped. + [bundle "bundle-0"] + uri = $HTTPD_URL/bundle-0.bundle + + [bundle "bundle-1"] + uri = $HTTPD_URL/bundle-1.bundle + + # Does not exist. Should be skipped. + [bundle "bundle-5"] + uri = $HTTPD_URL/bundle-5.bundle + EOF + + git clone --bundle-uri="$HTTPD_URL/bundle-list" clone-from clone-any-http && + git -C clone-from for-each-ref --format="%(objectname)" >oids && + git -C clone-any-http cat-file --batch-check