From patchwork Wed Feb 16 15:02:20 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: John Cai X-Patchwork-Id: 12748682 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3A7FAC433EF for ; Wed, 16 Feb 2022 15:02:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235337AbiBPPCt (ORCPT ); Wed, 16 Feb 2022 10:02:49 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:50792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235316AbiBPPCm (ORCPT ); Wed, 16 Feb 2022 10:02:42 -0500 Received: from mail-wm1-x334.google.com (mail-wm1-x334.google.com [IPv6:2a00:1450:4864:20::334]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0F6422AE27 for ; Wed, 16 Feb 2022 07:02:28 -0800 (PST) Received: by mail-wm1-x334.google.com with SMTP id i19so1376528wmq.5 for ; Wed, 16 Feb 2022 07:02:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:in-reply-to:references:from:date:subject:mime-version :content-transfer-encoding:fcc:to:cc; bh=xv4t2aZxqMGyWIvNovy4YtHVx+f8VAoqZNjMMU9DOpc=; b=ilLGyUcTrhLllgLfYmJgQDPQBKWvnnYbt9Hcno5hwmBZlEu3Bx2PqNGeu4vgBwK0GA DRl0guDGgQ6uAM7u0mX8w33o+P9pnPD2G9Ui7SKMjr9GzDFtCQNh3aazudmTaQhtTM1l R+hbtZTvaVOolgRshkkm3jC2EqQK8HANKfTmHDYENdb9V86eoLSygshnhd3dwGgck2pv xcJc9baiIl+ctDOSvGyQTgJis/cHMhfB1/Zk5Rm9pS1BCAw+hxdQVqNznTtE/eipuq8I 4O+emsEBHKD0Qlk91NC+LwnxnX0A7nM9p2NAeioIhqRWPidCAlfuZsst8ugxZrBLMqx5 FLIA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:in-reply-to:references:from:date :subject:mime-version:content-transfer-encoding:fcc:to:cc; bh=xv4t2aZxqMGyWIvNovy4YtHVx+f8VAoqZNjMMU9DOpc=; b=KecpahwoCKd2yhmQIGga06b7Xyx4366zsECNryCdUSyVf4NrjuZixDGiQFcYJdYio5 wCM4TLSEXaPdsGc/nw3WDWm1wKfOrYqMDVHgWRNhsyX/UEIodoPvbMs9k0S3Igq26IfB dh89SyU9YSbgCQUpao84MHygQyq+b7bhXoOZ2qgazO3qJX7SD7dWz6yJ1K8Q5WTlW4gW V4+m2WjeADdIVe9uWbsFTWld1zX5GOBUN4sCyUQspnQipK/FRYeJ2uhNvtUH0p5kfNeA MPIPDPhigYBTYHwB3npLdOjBg3ROHs05VQxu5ACept6xnebLtRXHxQYz8V1vSyy1pXU7 9njA== X-Gm-Message-State: AOAM5321zGe+rjh4qnxwhfhBwiCqDIrZoMV2Ldmtm/HQHsZhUQiR9txZ 36I1OB6zK9pMHyiZEc2GZemtPNFnr3I= X-Google-Smtp-Source: ABdhPJzXZhT17FL6g4P708l3VJody7a7Bby3rRwcV0IehL4M/1ZL716+QfnvA9AdkTUdmwScLC+70Q== X-Received: by 2002:a7b:c0d2:0:b0:37b:e9e6:75d6 with SMTP id s18-20020a7bc0d2000000b0037be9e675d6mr1950975wmh.39.1645023746186; Wed, 16 Feb 2022 07:02:26 -0800 (PST) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id o20sm18086223wmq.21.2022.02.16.07.02.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 16 Feb 2022 07:02:25 -0800 (PST) Message-Id: <8edf80574b8dd72ca8489df6e480cf6820b98070.1645023740.git.gitgitgadget@gmail.com> In-Reply-To: References: Date: Wed, 16 Feb 2022 15:02:20 +0000 Subject: [PATCH v8 4/4] cat-file: add --batch-command mode MIME-Version: 1.0 Fcc: Sent To: git@vger.kernel.org Cc: me@ttaylorr.com, phillip.wood123@gmail.com, avarab@gmail.com, e@80x24.org, bagasdotme@gmail.com, gitster@pobox.com, Eric Sunshine , Jonathan Tan , Christian Couder , John Cai , John Cai Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: John Cai From: John Cai Add a new flag --batch-command that accepts commands and arguments from stdin, similar to git-update-ref --stdin. At GitLab, we use a pair of long running cat-file processes when accessing object content. One for iterating over object metadata with --batch-check, and the other to grab object contents with --batch. However, if we had --batch-command, we wouldn't need to keep both processes around, and instead just have one --batch-command process where we can flip between getting object info, and getting object contents. Since we have a pair of cat-file processes per repository, this means we can get rid of roughly half of long lived git cat-file processes. Given there are many repositories being accessed at any given time, this can lead to huge savings. git cat-file --batch-command will enter an interactive command mode whereby the user can enter in commands and their arguments that get queued in memory: [arg1] [arg2] LF [arg1] [arg2] LF When --buffer mode is used, commands will be queued in memory until a flush command is issued that execute them: flush LF The reason for a flush command is that when a consumer process (A) talks to a git cat-file process (B) and interactively writes to and reads from it in --buffer mode, (A) needs to be able to control when the buffer is flushed to stdout. Currently, from (A)'s perspective, the only way is to either 1. kill (B)'s process 2. send an invalid object to stdin. 1. is not ideal from a performance perspective as it will require spawning a new cat-file process each time, and 2. is hacky and not a good long term solution. With this mechanism of queueing up commands and letting (A) issue a flush command, process (A) can control when the buffer is flushed and can guarantee it will receive all of the output when in --buffer mode. --batch-command also will not allow (B) to flush to stdout until a flush is received. This patch adds the basic structure for adding command which can be extended in the future to add more commands. It also adds the following two commands (on top of the flush command): contents LF info LF The contents command takes an argument and prints out the object contents. The info command takes an argument and prints out the object metadata. These can be used in the following way with --buffer: info LF contents LF contents LF info LF flush LF info LF flush LF When used without --buffer: info LF contents LF contents LF info LF info LF Helped-by: Ævar Arnfjörð Bjarmason Signed-off-by: John Cai --- Documentation/git-cat-file.txt | 42 +++++++++- builtin/cat-file.c | 140 ++++++++++++++++++++++++++++++++- t/README | 3 + t/t1006-cat-file.sh | 107 ++++++++++++++++++++++++- 4 files changed, 286 insertions(+), 6 deletions(-) diff --git a/Documentation/git-cat-file.txt b/Documentation/git-cat-file.txt index bef76f4dd06..70c5b4f12d1 100644 --- a/Documentation/git-cat-file.txt +++ b/Documentation/git-cat-file.txt @@ -96,6 +96,33 @@ OPTIONS need to specify the path, separated by whitespace. See the section `BATCH OUTPUT` below for details. +--batch-command:: +--batch-command=:: + Enter a command mode that reads commands and arguments from stdin. May + only be combined with `--buffer`, `--textconv` or `--filters`. In the + case of `--textconv` or `--filters`, the input lines also need to specify + the path, separated by whitespace. See the section `BATCH OUTPUT` below + for details. ++ +`--batch-command` recognizes the following commands: ++ +-- +contents :: + Print object contents for object reference ``. This corresponds to + the output of `--batch`. + +info :: + Print object info for object reference ``. This corresponds to the + output of `--batch-check`. + +flush:: + Used with `--buffer` to execute all preceding commands that were issued + since the beginning or since the last flush was issued. When `--buffer` + is used, no output will come until a `flush` is issued. When `--buffer` + is not used, commands are flushed each time without issuing `flush`. +-- ++ + --batch-all-objects:: Instead of reading a list of objects on stdin, perform the requested batch operation on all objects in the repository and @@ -110,7 +137,7 @@ OPTIONS that a process can interactively read and write from `cat-file`. With this option, the output uses normal stdio buffering; this is much more efficient when invoking - `--batch-check` on a large number of objects. + `--batch-check` or `--batch-command` on a large number of objects. --unordered:: When `--batch-all-objects` is in use, visit objects in an @@ -202,6 +229,13 @@ from stdin, one per line, and print information about them. By default, the whole line is considered as an object, as if it were fed to linkgit:git-rev-parse[1]. +When `--batch-command` is given, `cat-file` will read commands from stdin, +one per line, and print information based on the command given. With +`--batch-command`, the `info` command followed by an object will print +information about the object the same way `--batch-check` would, and the +`contents` command followed by an object prints contents in the same way +`--batch` would. + You can specify the information shown for each object by using a custom ``. The `` is copied literally to stdout for each object, with placeholders of the form `%(atom)` expanded, followed by a @@ -237,9 +271,9 @@ newline. The available atoms are: If no format is specified, the default format is `%(objectname) %(objecttype) %(objectsize)`. -If `--batch` is specified, the object information is followed by the -object contents (consisting of `%(objectsize)` bytes), followed by a -newline. +If `--batch` is specified, or if `--batch-command` is used with the `contents` +command, the object information is followed by the object contents (consisting +of `%(objectsize)` bytes), followed by a newline. For example, `--batch` without a custom format would produce: diff --git a/builtin/cat-file.c b/builtin/cat-file.c index 5e38af82af1..39d486dd737 100644 --- a/builtin/cat-file.c +++ b/builtin/cat-file.c @@ -20,6 +20,7 @@ enum batch_mode { BATCH_MODE_CONTENTS, BATCH_MODE_INFO, + BATCH_MODE_QUEUE_AND_DISPATCH, }; struct batch_options { @@ -513,6 +514,132 @@ static int batch_unordered_packed(const struct object_id *oid, data); } +typedef void (*parse_cmd_fn_t)(struct batch_options *, const char *, + struct strbuf *, struct expand_data *); + +struct queued_cmd { + parse_cmd_fn_t fn; + char *line; +}; + +static void parse_cmd_contents(struct batch_options *opt, + const char *line, + struct strbuf *output, + struct expand_data *data) +{ + opt->batch_mode = BATCH_MODE_CONTENTS; + batch_one_object(line, output, opt, data); +} + +static void parse_cmd_info(struct batch_options *opt, + const char *line, + struct strbuf *output, + struct expand_data *data) +{ + opt->batch_mode = BATCH_MODE_INFO; + batch_one_object(line, output, opt, data); +} + +/* Loop through each queued_cmd, dispatch the function, free the + * memory associated with line so the cmd array can be reused. + * Callers must set nr back to 0 in order to reuse the cmd array. + */ +static void dispatch_calls(struct batch_options *opt, + struct strbuf *output, + struct expand_data *data, + struct queued_cmd *cmd, + int nr) +{ + int i; + + if (!opt->buffer_output) + die(_("flush is only for --buffer mode")); + + for (i = 0; i < nr; i++) { + cmd[i].fn(opt, cmd[i].line, output, data); + FREE_AND_NULL(cmd[i].line); + } + + fflush(stdout); +} + +static const struct parse_cmd { + const char *name; + parse_cmd_fn_t fn; + unsigned takes_args; +} commands[] = { + { "contents", parse_cmd_contents, 1}, + { "info", parse_cmd_info, 1}, + { "flush", NULL, 0}, +}; + +static void batch_objects_command(struct batch_options *opt, + struct strbuf *output, + struct expand_data *data) +{ + struct strbuf input = STRBUF_INIT; + struct queued_cmd *queued_cmd = NULL; + size_t alloc = 0, nr = 0; + + while (!strbuf_getline(&input, stdin)) { + int i; + const struct parse_cmd *cmd = NULL; + const char *p = NULL, *cmd_end; + struct queued_cmd call = {0}; + + if (!input.len) + die(_("empty command in input")); + if (isspace(*input.buf)) + die(_("whitespace before command: '%s'"), input.buf); + + for (i = 0; i < ARRAY_SIZE(commands); i++) { + if (!skip_prefix(input.buf, commands[i].name, &cmd_end)) + continue; + + cmd = &commands[i]; + if (cmd->takes_args) { + if (*cmd_end != ' ') + die(_("%s requires arguments"), + commands[i].name); + + p = cmd_end + 1; + } else if (*cmd_end) { + die(_("%s takes no arguments"), + commands[i].name); + } + + break; + } + + if (!cmd) + die(_("unknown command: '%s'"), input.buf); + + if (!strcmp(cmd->name, "flush")) { + dispatch_calls(opt, output, data, queued_cmd, nr); + nr = 0; + continue; + } + + if (!opt->buffer_output) { + cmd->fn(opt, p, output, data); + continue; + } + + ALLOC_GROW(queued_cmd, nr + 1, alloc); + call.fn = cmd->fn; + call.line = xstrdup_or_null(p); + queued_cmd[nr++] = call; + } + + if (opt->buffer_output && + nr && + !git_env_bool("GIT_TEST_CAT_FILE_NO_FLUSH_ON_EXIT", 0)) + dispatch_calls(opt, output, data, queued_cmd, nr); + + free(queued_cmd); + strbuf_release(&input); +} + static int batch_objects(struct batch_options *opt) { struct strbuf input = STRBUF_INIT; @@ -595,6 +722,10 @@ static int batch_objects(struct batch_options *opt) save_warning = warn_on_object_refname_ambiguity; warn_on_object_refname_ambiguity = 0; + if (opt->batch_mode == BATCH_MODE_QUEUE_AND_DISPATCH) { + batch_objects_command(opt, &output, &data); + goto cleanup; + } while (strbuf_getline(&input, stdin) != EOF) { if (data.split_on_whitespace) { /* @@ -613,6 +744,7 @@ static int batch_objects(struct batch_options *opt) batch_one_object(input.buf, &output, opt, &data); } + cleanup: strbuf_release(&input); strbuf_release(&output); warn_on_object_refname_ambiguity = save_warning; @@ -645,6 +777,8 @@ static int batch_option_callback(const struct option *opt, bo->batch_mode = BATCH_MODE_CONTENTS; else if (!strcmp(opt->long_name, "batch-check")) bo->batch_mode = BATCH_MODE_INFO; + else if (!strcmp(opt->long_name, "batch-command")) + bo->batch_mode = BATCH_MODE_QUEUE_AND_DISPATCH; else BUG("%s given to batch-option-callback", opt->long_name); @@ -666,7 +800,7 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix) N_("git cat-file "), N_("git cat-file (-e | -p) "), N_("git cat-file (-t | -s) [--allow-unknown-type] "), - N_("git cat-file (--batch | --batch-check) [--batch-all-objects]\n" + N_("git cat-file (--batch | --batch-check | --batch-command) [--batch-all-objects]\n" " [--buffer] [--follow-symlinks] [--unordered]\n" " [--textconv | --filters]"), N_("git cat-file (--textconv | --filters)\n" @@ -695,6 +829,10 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix) N_("like --batch, but don't emit "), PARSE_OPT_OPTARG | PARSE_OPT_NONEG, batch_option_callback), + OPT_CALLBACK_F(0, "batch-command", &batch, N_("format"), + N_("read commands from stdin"), + PARSE_OPT_OPTARG | PARSE_OPT_NONEG, + batch_option_callback), OPT_CMDMODE(0, "batch-all-objects", &opt, N_("with --batch[-check]: ignores stdin, batches all known objects"), 'b'), /* Batch-specific options */ diff --git a/t/README b/t/README index f48e0542cdc..bcd813b0c59 100644 --- a/t/README +++ b/t/README @@ -472,6 +472,9 @@ a test and then fails then the whole test run will abort. This can help to make sure the expected tests are executed and not silently skipped when their dependency breaks or is simply not present in a new environment. +GIT_TEST_CAT_FILE_NO_FLUSH_ON_EXIT=, when true will prevent cat-file +--batch-command from flushing to output on exit. + Naming Tests ------------ diff --git a/t/t1006-cat-file.sh b/t/t1006-cat-file.sh index 2d52851dadc..74f0e36b69e 100755 --- a/t/t1006-cat-file.sh +++ b/t/t1006-cat-file.sh @@ -182,6 +182,24 @@ $content" test_cmp expect actual ' + for opt in --buffer --no-buffer + do + test -z "$content" || + test_expect_success "--batch-command $opt output of $type content is correct" ' + maybe_remove_timestamp "$batch_output" $no_ts >expect && + maybe_remove_timestamp "$(test_write_lines "contents $sha1" \ + | git cat-file --batch-command $opt)" $no_ts >actual && + test_cmp expect actual + ' + + test_expect_success "--batch-command $opt output of $type info is correct" ' + echo "$sha1 $type $size" >expect && + test_write_lines "info $sha1" \ + | git cat-file --batch-command $opt >actual && + test_cmp expect actual + ' + done + test_expect_success "custom --batch-check format" ' echo "$type $sha1" >expect && echo $sha1 | git cat-file --batch-check="%(objecttype) %(objectname)" >actual && @@ -229,6 +247,22 @@ test_expect_success "setup" ' run_tests 'blob' $hello_sha1 $hello_size "$hello_content" "$hello_content" +test_expect_success '--batch-command --buffer with flush for blob info' ' + echo "$hello_sha1 blob $hello_size" >expect && + test_write_lines "info $hello_sha1" "flush" | \ + GIT_TEST_CAT_FILE_NO_FLUSH_ON_EXIT=1 \ + git cat-file --batch-command --buffer >actual && + test_cmp expect actual +' + +test_expect_success '--batch-command --buffer without flush for blob info' ' + touch output && + test_write_lines "info $hello_sha1" | \ + GIT_TEST_CAT_FILE_NO_FLUSH_ON_EXIT=1 \ + git cat-file --batch-command --buffer >>output && + test_must_be_empty output +' + test_expect_success '--batch-check without %(rest) considers whole line' ' echo "$hello_sha1 blob $hello_size" >expect && git update-index --add --cacheinfo 100644 $hello_sha1 "white space" && @@ -272,7 +306,7 @@ test_expect_success \ "Reach a blob from a tag pointing to it" \ "test '$hello_content' = \"\$(git cat-file blob $tag_sha1)\"" -for batch in batch batch-check +for batch in batch batch-check batch-command do for opt in t s e p do @@ -378,6 +412,42 @@ test_expect_success "--batch-check with multiple sha1s gives correct format" ' "$(echo_without_newline "$batch_check_input" | git cat-file --batch-check)" ' +test_expect_success '--batch-command with multiple info calls gives correct format' ' + cat >expect <<-EOF && + $hello_sha1 blob $hello_size + $tree_sha1 tree $tree_size + $commit_sha1 commit $commit_size + $tag_sha1 tag $tag_size + deadbeef missing + EOF + + test_write_lines "info $hello_sha1"\ + "info $tree_sha1"\ + "info $commit_sha1"\ + "info $tag_sha1"\ + "info deadbeef" | git cat-file --batch-command --buffer >actual && + test_cmp expect actual +' + +test_expect_success '--batch-command with multiple command calls gives correct format' ' + remove_timestamp >expect <<-EOF && + $hello_sha1 blob $hello_size + $hello_content + $commit_sha1 commit $commit_size + $commit_content + $tag_sha1 tag $tag_size + $tag_content + deadbeef missing + EOF + + test_write_lines "contents $hello_sha1"\ + "contents $commit_sha1"\ + "contents $tag_sha1"\ + "contents deadbeef"\ + "flush" | git cat-file --batch-command --buffer | remove_timestamp >actual && + test_cmp expect actual +' + test_expect_success 'setup blobs which are likely to delta' ' test-tool genrandom foo 10240 >foo && { cat foo && echo plus; } >foo-plus && @@ -968,5 +1038,40 @@ test_expect_success 'cat-file --batch-all-objects --batch-check ignores replace' echo "$orig commit $orig_size" >expect && test_cmp expect actual ' +test_expect_success 'batch-command empty command' ' + echo "" >cmd && + test_expect_code 128 git cat-file --batch-command err && + grep "^fatal:.*empty command in input.*" err +' + +test_expect_success 'batch-command whitespace before command' ' + echo " info deadbeef" >cmd && + test_expect_code 128 git cat-file --batch-command err && + grep "^fatal:.*whitespace before command.*" err +' + +test_expect_success 'batch-command unknown command' ' + echo unknown_command >cmd && + test_expect_code 128 git cat-file --batch-command err && + grep "^fatal:.*unknown command.*" err +' + +test_expect_success 'batch-command missing arguments' ' + echo "info" >cmd && + test_expect_code 128 git cat-file --batch-command err && + grep "^fatal:.*info requires arguments.*" err +' + +test_expect_success 'batch-command flush with arguments' ' + echo "flush arg" >cmd && + test_expect_code 128 git cat-file --batch-command --buffer err && + grep "^fatal:.*flush takes no arguments.*" err +' + +test_expect_success 'batch-command flush without --buffer' ' + echo "flush" >cmd && + test_expect_code 128 git cat-file --batch-command err && + grep "^fatal:.*flush is only for --buffer mode.*" err +' test_done