From patchwork Wed Nov 14 00:25:49 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Elijah Newren X-Patchwork-Id: 10681739 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BC5F2139B for ; Wed, 14 Nov 2018 00:26:27 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A874629508 for ; Wed, 14 Nov 2018 00:26:27 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9C6BD29562; Wed, 14 Nov 2018 00:26:27 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 592782B5F2 for ; Wed, 14 Nov 2018 00:26:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731357AbeKNK1H (ORCPT ); Wed, 14 Nov 2018 05:27:07 -0500 Received: from mx0a-00153501.pphosted.com ([67.231.148.48]:38482 "EHLO mx0a-00153501.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731048AbeKNK1F (ORCPT ); Wed, 14 Nov 2018 05:27:05 -0500 Received: from pps.filterd (m0131697.ppops.net [127.0.0.1]) by mx0a-00153501.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id wAE0IbQt024221; Tue, 13 Nov 2018 16:26:03 -0800 Received: from mail.palantir.com ([8.4.231.70]) by mx0a-00153501.pphosted.com with ESMTP id 2nr7by051r-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=OK); Tue, 13 Nov 2018 16:26:02 -0800 Received: from sj-prod-exch-02.YOJOE.local (10.129.18.29) by sj-prod-exch-02.YOJOE.local (10.129.18.29) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1531.3; Tue, 13 Nov 2018 16:25:55 -0800 Received: from smtp-transport.yojoe.local (10.129.56.124) by sj-prod-exch-02.YOJOE.local (10.129.18.29) with Microsoft SMTP Server id 15.1.1531.3 via Frontend Transport; Tue, 13 Nov 2018 16:25:55 -0800 Received: from newren2-linux.yojoe.local (newren2-linux.pa.palantir.tech [10.100.71.66]) by smtp-transport.yojoe.local (Postfix) with ESMTPS id EA3FA2212286; Tue, 13 Nov 2018 16:26:00 -0800 (PST) From: Elijah Newren To: CC: , , , , , , Elijah Newren Subject: [PATCH v2 00/11] fast export and import fixes and features Date: Tue, 13 Nov 2018 16:25:49 -0800 Message-ID: <20181114002600.29233-1-newren@gmail.com> X-Mailer: git-send-email 2.19.1.1063.g2b8e4a4f82.dirty In-Reply-To: <20181111062312.16342-1-newren@gmail.com> References: <20181111062312.16342-1-newren@gmail.com> MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-11-13_17:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=4 phishscore=0 bulkscore=0 spamscore=0 clxscore=1034 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1811140001 Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This is a series of small fixes and features for fast-export and fast-import, mostly on the fast-export side. Changes since v1 (full range-diff below): - used {tilde} in asciidoc documentation to avoid subscripting and escaping problems - renamed ABORT/ERROR enum values to help avoid further misusage - multiple small testcase cleanups (use $ZERO_OID, remove grep -A, etc.) - add FIXME comment to code about string_list usage - record Peff's idea for a future optimization in patch 8 commit message (is there a better place to put that??) - New patch (9/11): remove the unmaintained copy of fast-import stream format documentation at the beginning of fast-import.c - Rewrite commit message for 10/11 to match the wording Peff liked better, s/originally/original-oid/, and add documentation to git-fast-import.txt - Rewrite commit message for 11/11; the last one didn't make sense to Peff. I hope this one does. Elijah Newren (11): git-fast-import.txt: fix documentation for --quiet option git-fast-export.txt: clarify misleading documentation about rev-list args fast-export: use value from correct enum fast-export: avoid dying when filtering by paths and old tags exist fast-export: move commit rewriting logic into a function for reuse fast-export: when using paths, avoid corrupt stream with non-existent mark fast-export: ensure we export requested refs fast-export: add --reference-excluded-parents option fast-import: remove unmaintained duplicate documentation fast-export: add a --show-original-ids option to show original names fast-export: add --always-show-modify-after-rename Documentation/git-fast-export.txt | 34 +++++- Documentation/git-fast-import.txt | 23 +++- builtin/fast-export.c | 172 ++++++++++++++++++++++-------- fast-import.c | 166 +++------------------------- t/t9350-fast-export.sh | 116 +++++++++++++++++++- 5 files changed, 308 insertions(+), 203 deletions(-) 1: 0744f65b0d = 1: 8870fb1340 git-fast-import.txt: fix documentation for --quiet option 2: aba1e22fdd ! 2: 16d1c3e22d git-fast-export.txt: clarify misleading documentation about rev-list args @@ -13,7 +13,7 @@ current master reference to be exported along with all objects - added since its 10th ancestor commit. + added since its 10th ancestor commit and all files common to -+ master\~9 and master~10. ++ master{tilde}9 and master{tilde}10. EXAMPLES -------- 3: 6983e845b2 < -: ---------- fast-export: use value from correct enum -: ---------- > 3: e19f6b36f9 fast-export: use value from correct enum 4: 761ba324d5 ! 4: 2b305561d5 fast-export: avoid dying when filtering by paths and old tags exist @@ -49,18 +49,14 @@ + ( + cd rewrite_tag_predating_pathspecs && + -+ touch ignored && -+ git add ignored && + test_commit initial && + + git tag -a -m "Some old tag" v0.0.0.0.0.0.1 && + -+ echo foo >bar && -+ git add bar && -+ test_commit add-bar && ++ test_commit bar && + -+ git fast-export --tag-of-filtered-object=rewrite --all -- bar >output && -+ grep -A 1 refs/tags/v0.0.0.0.0.0.1 output | grep -E ^from.0{40} ++ git fast-export --tag-of-filtered-object=rewrite --all -- bar.t >output && ++ grep from.$ZERO_OID output + ) +' + 5: 64e9f0d360 = 5: 607b1dc2b2 fast-export: move commit rewriting logic into a function for reuse 6: fd14d9749a ! 6: ec1862e858 fast-export: when using paths, avoid corrupt stream with non-existent mark @@ -54,22 +54,18 @@ + ( + cd avoid_non_existent_mark && + -+ touch important-path && -+ git add important-path && -+ test_commit initial && ++ test_commit important-path && + -+ touch ignored && -+ git add ignored && -+ test_commit whatever && ++ test_commit ignored && + + git branch A && + git branch B && + -+ echo foo >>important-path && -+ git add important-path && ++ echo foo >>important-path.t && ++ git add important-path.t && + test_commit more changes && + -+ git fast-export --all -- important-path | git fast-import --force ++ git fast-export --all -- important-path.t | git fast-import --force + ) +' + 7: 4e67a2bc7f ! 7: 9da26e3ccb fast-export: ensure we export requested refs @@ -21,9 +21,6 @@ were just silently omitted from being exported despite having been explicitly requested for export. - NOTE: The usage of string_list should really be replaced with the - strmap proposal, once it materializes. - Signed-off-by: Elijah Newren diff --git a/builtin/fast-export.c b/builtin/fast-export.c @@ -41,6 +38,12 @@ export_blob(&diff_queued_diff.queue[i]->two->oid); refname = *revision_sources_at(&revision_sources, commit); ++ /* ++ * FIXME: string_list_remove() below for each ref is overall ++ * O(N^2). Compared to a history walk and diffing trees, this is ++ * just lost in the noise in practice. However, theoretically a ++ * repo may have enough refs for this to become slow. ++ */ + string_list_remove(&extra_refs, refname, 0); if (anonymize) { refname = anonymize_refname(refname); 8: be02337f29 ! 8: 7e5fe2f02e fast-export: add --reference-excluded-parents option @@ -30,6 +30,15 @@ repository which already contains the necessary commits (much like the restriction imposed when using --no-data). + Note from Peff: + I think we might be able to do a little more optimization here. If + we're exporting HEAD^..HEAD and there's an object in HEAD^ which is + unchanged in HEAD, I think we'd still print it (because it would not + be marked SHOWN), but we could omit it (by walking the tree of the + boundary commits and marking them shown). I don't think it's a + blocker for what you're doing here, but just a possible future + optimization. + Signed-off-by: Elijah Newren diff --git a/Documentation/git-fast-export.txt b/Documentation/git-fast-export.txt @@ -41,14 +50,15 @@ +--reference-excluded-parents:: + By default, running a command such as `git fast-export -+ master~5..master` will not include the commit master\~5 and -+ will make master\~4 no longer have master\~5 as a parent (though -+ both the old master\~4 and new master~4 will have all the same -+ files). Use --reference-excluded-parents to instead have the -+ the stream refer to commits in the excluded range of history -+ by their sha1sum. Note that the resulting stream can only be -+ used by a repository which already contains the necessary -+ parent commits. ++ master~5..master` will not include the commit master{tilde}5 ++ and will make master{tilde}4 no longer have master{tilde}5 as ++ a parent (though both the old master{tilde}4 and new ++ master{tilde}4 will have all the same files). Use ++ --reference-excluded-parents to instead have the the stream ++ refer to commits in the excluded range of history by their ++ sha1sum. Note that the resulting stream can only be used by a ++ repository which already contains the necessary parent ++ commits. + --refspec:: Apply the specified refspec to each ref exported. Multiple of them can @@ -58,10 +68,10 @@ to export. For example, `master~10..master` causes the current master reference to be exported along with all objects - added since its 10th ancestor commit and all files common to -- master\~9 and master~10. +- master{tilde}9 and master{tilde}10. + added since its 10th ancestor commit and (unless the + --reference-excluded-parents option is specified) all files -+ common to master\~9 and master~10. ++ common to master{tilde}9 and master{tilde}10. EXAMPLES -------- -: ---------- > 9: 14306a8436 fast-import: remove unmaintained duplicate documentation 9: 7ab314849d ! 10: 72487a61e4 fast-export: add a --show-original-ids option to show original names @@ -2,16 +2,24 @@ fast-export: add a --show-original-ids option to show original names - Knowing the original names (hashes) of commits, blobs, and tags can - sometimes enable post-filtering that would otherwise be difficult or - impossible. In particular, the desire to rewrite commit messages which - refer to other prior commits (on top of whatever other filtering is - being done) is very difficult without knowing the original names of each - commit. + Knowing the original names (hashes) of commits can sometimes enable + post-filtering that would otherwise be difficult or impossible. In + particular, the desire to rewrite commit messages which refer to other + prior commits (on top of whatever other filtering is being done) is + very difficult without knowing the original names of each commit. + + In addition, knowing the original names (hashes) of blobs can allow + filtering by blob-id without requiring re-hashing the content of the + blob, and is thus useful as a small optimization. + + Once we add original ids for both commits and blobs, we may as well + add them for tags too for completeness. Perhaps someone will have a + use for them. This commit teaches a new --show-original-ids option to fast-export - which will make it add a 'originally ' line to blob, commits, and - tags. It also teaches fast-import to parse (and ignore) such lines. + which will make it add a 'original-oid ' line to blob, commits, + and tags. It also teaches fast-import to parse (and ignore) such + lines. Signed-off-by: Elijah Newren @@ -19,12 +27,12 @@ --- a/Documentation/git-fast-export.txt +++ b/Documentation/git-fast-export.txt @@ - used by a repository which already contains the necessary - parent commits. + repository which already contains the necessary parent + commits. +--show-original-ids:: + Add an extra directive to the output for commits and blobs, -+ `originally `. While such directives will likely be ++ `original-oid `. While such directives will likely be + ignored by importers such as git-fast-import, it may be useful + for intermediary filters (e.g. for rewriting commit messages + which refer to older commits, or for stripping blobs by id). @@ -33,6 +41,54 @@ Apply the specified refspec to each ref exported. Multiple of them can be specified. + diff --git a/Documentation/git-fast-import.txt b/Documentation/git-fast-import.txt + --- a/Documentation/git-fast-import.txt + +++ b/Documentation/git-fast-import.txt +@@ + .... + 'commit' SP LF + mark? ++ original-oid? + ('author' (SP )? SP LT GT SP LF)? + 'committer' (SP )? SP LT GT SP LF + data +@@ + to another object simply by reusing the same `` in another + `mark` command. + ++`original-oid` ++~~~~~~~~~~~~~~ ++Provides the name of the object in the original source control system. ++fast-import will simply ignore this directive, but filter processes ++which operate on and modify the stream before feeding to fast-import ++may have uses for this information ++ ++.... ++ 'original-oid' SP LF ++.... ++ ++where `` is any string not containing LF. ++ + `tag` + ~~~~~ + Creates an annotated tag referring to a specific commit. To create +@@ + .... + 'tag' SP LF + 'from' SP LF ++ original-oid? + 'tagger' (SP )? SP LT GT SP LF + data + .... +@@ + .... + 'blob' LF + mark? ++ original-oid? + data + .... + + diff --git a/builtin/fast-export.c b/builtin/fast-export.c --- a/builtin/fast-export.c +++ b/builtin/fast-export.c @@ -51,7 +107,7 @@ - printf("blob\nmark :%"PRIu32"\ndata %lu\n", last_idnum, size); + printf("blob\nmark :%"PRIu32"\n", last_idnum); + if (show_original_ids) -+ printf("originally %s\n", oid_to_hex(oid)); ++ printf("original-oid %s\n", oid_to_hex(oid)); + printf("data %lu\n", size); if (size && fwrite(buf, size, 1, stdout) != 1) die_errno("could not write blob '%s'", oid_to_hex(oid)); @@ -64,7 +120,7 @@ - refname, last_idnum, + printf("commit %s\nmark :%"PRIu32"\n", refname, last_idnum); + if (show_original_ids) -+ printf("originally %s\n", oid_to_hex(&commit->object.oid)); ++ printf("original-oid %s\n", oid_to_hex(&commit->object.oid)); + printf("%.*s\n%.*s\ndata %u\n%s", (int)(author_end - author), author, (int)(committer_end - committer), committer, @@ -77,7 +133,7 @@ - name, tagged_mark, + printf("tag %s\nfrom :%d\n", name, tagged_mark); + if (show_original_ids) -+ printf("originally %s\n", oid_to_hex(&tag->object.oid)); ++ printf("original-oid %s\n", oid_to_hex(&tag->object.oid)); + printf("%.*s%sdata %d\n%.*s\n", (int)(tagger_end - tagger), tagger, tagger == tagger_end ? "" : "\n", @@ -96,44 +152,13 @@ --- a/fast-import.c +++ b/fast-import.c @@ - - new_blob ::= 'blob' lf - mark? -+ originally? - file_content; - file_content ::= data; - - new_commit ::= 'commit' sp ref_str lf - mark? -+ originally? - ('author' (sp name)? sp '<' email '>' sp when lf)? - 'committer' (sp name)? sp '<' email '>' sp when lf - commit_msg -@@ - - new_tag ::= 'tag' sp tag_str lf - 'from' sp commit-ish lf -+ originally? - ('tagger' (sp name)? sp '<' email '>' sp when lf)? - tag_msg; - tag_msg ::= data; -@@ - data ::= (delimited_data | exact_data) - lf?; - -+ originally ::= 'originally' sp not_lf+ lf -+ - # note: delim may be any string but must not contain lf. - # data_line may contain any data but must not be exactly - # delim. -@@ next_mark = 0; } +static void parse_original_identifier(void) +{ + const char *v; -+ if (skip_prefix(command_buf.buf, "originally ", &v)) ++ if (skip_prefix(command_buf.buf, "original-oid ", &v)) + read_next_command(); +} + @@ -160,7 +185,7 @@ die("Invalid ref name or SHA1 expression: %s", from); read_next_command(); -+ /* originally ... */ ++ /* original-oid ... */ + parse_original_identifier(); + /* tagger ... */ @@ -177,7 +202,7 @@ +test_expect_success 'fast-export --show-original-ids' ' + + git fast-export --show-original-ids master >output && -+ grep ^originally output| sed -e s/^originally.// | sort >actual && ++ grep ^original-oid output| sed -e s/^original-oid.// | sort >actual && + git rev-list --objects master muss >objects-and-names && + awk "{print \$1}" objects-and-names | sort >commits-trees-blobs && + comm -23 actual commits-trees-blobs >unfound && 10: 82735bcbde ! 11: 1796373474 fast-export: add --always-show-modify-after-rename @@ -2,29 +2,53 @@ fast-export: add --always-show-modify-after-rename - fast-export output is traditionally used as an input to a fast-import - program, but it is also useful to help gather statistics about the - history of a repository (particularly when --no-data is also passed). - For example, two of the types of information we may want to collect - could include: - 1) general information about renames that have occurred - 2) what the biggest objects in a repository are and what names - they appear under. + I wanted a way to gather all the following information efficiently + (with as few history traversals as possible): + * Get all blob sizes + * Map blob shas to filename(s) they appeared under in the history + * Find when files and directories were deleted (and whether they + were later reinstated, since that means they aren't actually gone) + * Find sets of filenames referring to the same logical 'file'. (e.g. + foo->bar in commit A and bar->baz in commit B mean that + {foo,bar,baz} refer to the same 'file', so someone wanting to just + "keep baz and its history" need all versions of those three + filenames). I need to know about things like another foo or bar + being introduced after the rename though, since that breaks the + connection between filenames) + and then I would generate various aggregations on the data and display + some type of report for the user. - The first bit of information can be gathered by just passing -M to - fast-export. The second piece of information can partially be gotten - from running - git cat-file --batch-check --batch-all-objects - However, that only shows what the biggest objects in the repository are - and their sizes, not what names those objects appear as or what commits - they were introduced in. We can get that information from fast-export, - but when we only see + The only way I know of to get blob sizes is via + cat-file --batch-all-objects --batch-check + + The rest of the data would traditionally be gathered from a log command, + e.g. + + git log --format='%H%n%P%n%cd' --date=short --topo-order --reverse \ + -M --diff-filter=RAMD --no-abbrev --raw -c + + however, parsing log output seems slightly dangerous given that it is a + porcelain command. While we have specified --format and --raw to try + to avoid the most obvious problems, I'm still slightly concerned about + --date=short, the combinations of --raw and -c, options that might + colorize the output, and also the --diff-filter (there is no current + option named --no-find-copies or --no-break-rewrites, but what if those + turn on by default in the future much as we changed the default with + detecting renames?). Each of those is a small worry, but they add up. + + A command meant for data serialization, such as fast-export, seems like + a better candidate for this job. There's just one missing item: in + order to connect blob sizes to filenames, I need fast-export to tell me + the blob sha1sum of any file changes. It does this for modifies, but + not always for renames. In particular, if a file is a 100% rename, it + only prints R oldname newname instead of R oldname newname M 100644 $SHA1 newname - then it makes the job more difficult. Add an option which allows us to - force the latter output even when commits have exact renames of files. + as occurs when there is a rename+modify. Add an option which allows us + to force the latter output even when commits have exact renames of + files. Signed-off-by: Elijah Newren