From a2c75526d21939d5d4e36dbbd6093a5e2c14c39f Mon Sep 17 00:00:00 2001 From: John Cai Date: Fri, 18 Feb 2022 18:23:11 +0000 Subject: [PATCH 1/4] cat-file: rename cmdmode to transform_mode In the next patch, we will add an enum on the batch_options struct that indicates which type of batch operation will be used: --batch, --batch-check and the soon to be --batch-command that will read commands from stdin. --batch-command mode might get confused with the cmdmode flag. There is value in renaming cmdmode in any case. cmdmode refers to how the result output of the blob will be transformed, either according to --filter or --textconv. So transform_mode is a more descriptive name for the flag. Rename cmdmode to transform_mode in cat-file.c Signed-off-by: John Cai Signed-off-by: Junio C Hamano --- builtin/cat-file.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/builtin/cat-file.c b/builtin/cat-file.c index 7b3f42950e..5f015e7109 100644 --- a/builtin/cat-file.c +++ b/builtin/cat-file.c @@ -24,7 +24,7 @@ struct batch_options { int buffer_output; int all_objects; int unordered; - int cmdmode; /* may be 'w' or 'c' for --filters or --textconv */ + int transform_mode; /* may be 'w' or 'c' for --filters or --textconv */ const char *format; }; @@ -302,19 +302,19 @@ static void print_object_or_die(struct batch_options *opt, struct expand_data *d if (data->type == OBJ_BLOB) { if (opt->buffer_output) fflush(stdout); - if (opt->cmdmode) { + if (opt->transform_mode) { char *contents; unsigned long size; if (!data->rest) die("missing path for '%s'", oid_to_hex(oid)); - if (opt->cmdmode == 'w') { + if (opt->transform_mode == 'w') { if (filter_object(data->rest, 0100644, oid, &contents, &size)) die("could not convert '%s' %s", oid_to_hex(oid), data->rest); - } else if (opt->cmdmode == 'c') { + } else if (opt->transform_mode == 'c') { enum object_type type; if (!textconv_object(the_repository, data->rest, 0100644, oid, @@ -326,7 +326,7 @@ static void print_object_or_die(struct batch_options *opt, struct expand_data *d die("could not convert '%s' %s", oid_to_hex(oid), data->rest); } else - BUG("invalid cmdmode: %c", opt->cmdmode); + BUG("invalid transform_mode: %c", opt->transform_mode); batch_write(opt, contents, size); free(contents); } else { @@ -529,7 +529,7 @@ static int batch_objects(struct batch_options *opt) strbuf_expand(&output, opt->format, expand_format, &data); data.mark_query = 0; strbuf_release(&output); - if (opt->cmdmode) + if (opt->transform_mode) data.split_on_whitespace = 1; /* @@ -742,7 +742,7 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix) /* Return early if we're in batch mode? */ if (batch.enabled) { if (opt_cw) - batch.cmdmode = opt; + batch.transform_mode = opt; else if (opt && opt != 'b') usage_msg_optf(_("'-%c' is incompatible with batch mode"), usage, options, opt); From ac4e58cab9a946d4c45f1db5ee7c79b6fb14bd67 Mon Sep 17 00:00:00 2001 From: John Cai Date: Fri, 18 Feb 2022 18:23:12 +0000 Subject: [PATCH 2/4] cat-file: introduce batch_mode enum to replace print_contents A future patch introduces a new --batch-command flag. Including --batch and --batch-check, we will have a total of three batch modes. print_contents is the only boolean on the batch_options sturct used to distinguish between the different modes. This makes the code harder to read. To reduce potential confusion, replace print_contents with an enum to help readability and clarity. Helped-by: Junio C Hamano Signed-off-by: John Cai Signed-off-by: Junio C Hamano --- builtin/cat-file.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/builtin/cat-file.c b/builtin/cat-file.c index 5f015e7109..5e38af82af 100644 --- a/builtin/cat-file.c +++ b/builtin/cat-file.c @@ -17,10 +17,15 @@ #include "object-store.h" #include "promisor-remote.h" +enum batch_mode { + BATCH_MODE_CONTENTS, + BATCH_MODE_INFO, +}; + struct batch_options { int enabled; int follow_symlinks; - int print_contents; + enum batch_mode batch_mode; int buffer_output; int all_objects; int unordered; @@ -386,7 +391,7 @@ static void batch_object_write(const char *obj_name, strbuf_addch(scratch, '\n'); batch_write(opt, scratch->buf, scratch->len); - if (opt->print_contents) { + if (opt->batch_mode == BATCH_MODE_CONTENTS) { print_object_or_die(opt, data); batch_write(opt, "\n", 1); } @@ -536,7 +541,7 @@ static int batch_objects(struct batch_options *opt) * If we are printing out the object, then always fill in the type, * since we will want to decide whether or not to stream. */ - if (opt->print_contents) + if (opt->batch_mode == BATCH_MODE_CONTENTS) data.info.typep = &data.type; if (opt->all_objects) { @@ -635,7 +640,14 @@ static int batch_option_callback(const struct option *opt, } bo->enabled = 1; - bo->print_contents = !strcmp(opt->long_name, "batch"); + + if (!strcmp(opt->long_name, "batch")) + bo->batch_mode = BATCH_MODE_CONTENTS; + else if (!strcmp(opt->long_name, "batch-check")) + bo->batch_mode = BATCH_MODE_INFO; + else + BUG("%s given to batch-option-callback", opt->long_name); + bo->format = arg; return 0; From 4cf5d53b62a8e5fce64db97f830e00fa38bd0994 Mon Sep 17 00:00:00 2001 From: John Cai Date: Fri, 18 Feb 2022 18:23:13 +0000 Subject: [PATCH 3/4] cat-file: add remove_timestamp helper maybe_remove_timestamp() takes arguments, but it would be useful to have a function that reads from stdin and strips the timestamp. This would allow tests to pipe data into a function to remove timestamps, and wouldn't have to always assign a variable. This is especially helpful when the data is multiple lines. Keep maybe_remove_timestamp() the same, but add a remove_timestamp helper that reads from stdin. The tests in the next patch will make use of this. Signed-off-by: John Cai Signed-off-by: Junio C Hamano --- t/t1006-cat-file.sh | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/t/t1006-cat-file.sh b/t/t1006-cat-file.sh index 145eee11df..2d52851dad 100755 --- a/t/t1006-cat-file.sh +++ b/t/t1006-cat-file.sh @@ -105,13 +105,18 @@ strlen () { } maybe_remove_timestamp () { - if test -z "$2"; then - echo_without_newline "$1" - else - echo_without_newline "$(printf '%s\n' "$1" | sed -e 's/ [0-9][0-9]* [-+][0-9][0-9][0-9][0-9]$//')" - fi + if test -z "$2"; then + echo_without_newline "$1" + else + echo_without_newline "$(printf '%s\n' "$1" | remove_timestamp)" + fi } +remove_timestamp () { + sed -e 's/ [0-9][0-9]* [-+][0-9][0-9][0-9][0-9]$//' +} + + run_tests () { type=$1 sha1=$2 From 440c705ea63253642c8f4761f80eb7a97a62b614 Mon Sep 17 00:00:00 2001 From: John Cai Date: Fri, 18 Feb 2022 18:23:14 +0000 Subject: [PATCH 4/4] cat-file: add --batch-command mode MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Signed-off-by: Junio C Hamano --- Documentation/git-cat-file.txt | 42 +++++++++- builtin/cat-file.c | 144 ++++++++++++++++++++++++++++++++- t/t1006-cat-file.sh | 120 ++++++++++++++++++++++++++- 3 files changed, 300 insertions(+), 6 deletions(-) diff --git a/Documentation/git-cat-file.txt b/Documentation/git-cat-file.txt index bef76f4dd0..70c5b4f12d 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 5e38af82af..e75e110302 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 +514,135 @@ 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); +} + +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); + + fflush(stdout); +} + +static void free_cmds(struct queued_cmd *cmd, size_t *nr) +{ + size_t i; + + for (i = 0; i < *nr; i++) + FREE_AND_NULL(cmd[i].line); + + *nr = 0; +} + + +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); + free_cmds(queued_cmd, &nr); + } else if (!opt->buffer_output) { + cmd->fn(opt, p, output, data); + } else { + 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_cmds(queued_cmd, &nr); + } + + free(queued_cmd); + strbuf_release(&input); +} + static int batch_objects(struct batch_options *opt) { struct strbuf input = STRBUF_INIT; @@ -595,6 +725,11 @@ 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 +748,7 @@ 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 +781,8 @@ 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 +804,7 @@ 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 +833,10 @@ 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/t1006-cat-file.sh b/t/t1006-cat-file.sh index 2d52851dad..1b85207694 100755 --- a/t/t1006-cat-file.sh +++ b/t/t1006-cat-file.sh @@ -182,12 +182,36 @@ $content" test_cmp expect actual ' + for opt in --buffer --no-buffer + do + test -z "$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 $sha1 | git cat-file --batch-check="%(objecttype) %(objectname)" >actual && test_cmp expect actual ' + test_expect_success "custom --batch-command format" ' + echo "$type $sha1" >expect && + echo "info $sha1" | git cat-file --batch-command="%(objecttype) %(objectname)" >actual && + test_cmp expect actual + ' + test_expect_success '--batch-check with %(rest)' ' echo "$type this is some extra content" >expect && echo "$sha1 this is some extra content" | @@ -229,6 +253,22 @@ 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 $hello_sha1 "white space" && @@ -272,7 +312,7 @@ test_expect_success \ "Reach a blob from a tag pointing to it" \ "test '$hello_content' = \"\$(git cat-file blob $tag_sha1)\"" -for batch in batch batch-check +for batch in batch batch-check batch-command do for opt in t s e p do @@ -378,6 +418,49 @@ test_expect_success "--batch-check with multiple sha1s gives correct format" ' "$(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 + + git cat-file --batch-command --buffer >actual <<-EOF && + info $hello_sha1 + info $tree_sha1 + info $commit_sha1 + info $tag_sha1 + info deadbeef + EOF + + 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 + + git cat-file --batch-command --buffer >actual_raw <<-EOF && + contents $hello_sha1 + contents $commit_sha1 + contents $tag_sha1 + contents deadbeef + flush + EOF + + remove_timestamp actual && + test_cmp expect actual +' + test_expect_success 'setup blobs which are likely to delta' ' test-tool genrandom foo 10240 >foo && { cat foo && echo plus; } >foo-plus && @@ -968,5 +1051,40 @@ test_expect_success 'cat-file --batch-all-objects --batch-check ignores replace' echo "$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