From: Derrick Stolee via GitGitGadget Date: Tue, 31 Jan 2023 13:29:12 GMT Subject: [PATCH v3 04/11] bundle-uri: parse bundle.heuristic=creationToken Message-ID: <49bf10e0fd4468720cd86cc47e425bf446a1a4f7.1675171759.git.gitgitgadget@gmail.com> In-Reply-To: From: Derrick Stolee The bundle.heuristic value communicates that the bundle list is organized to make use of the bundle..creationToken values that may be provided in the bundle list. Those values will create a total order on the bundles, allowing the Git client to download them in a specific order and even remember previously-downloaded bundles by storing the maximum creation token value. Before implementing any logic that parses or uses the bundle..creationToken values, teach Git to parse the bundle.heuristic value from a bundle list. We can use 'test-tool bundle-uri' to print the heuristic value and verify that the parsing works correctly. As an extra precaution, create the internal 'heuristics' array to be a list of (enum, string) pairs so we can iterate through the array entries carefully, regardless of the enum values. Signed-off-by: Derrick Stolee --- Documentation/config/bundle.txt | 7 +++++++ bundle-uri.c | 34 +++++++++++++++++++++++++++++++++ bundle-uri.h | 14 ++++++++++++++ t/t5750-bundle-uri-parse.sh | 19 ++++++++++++++++++ 4 files changed, 74 insertions(+) diff --git a/Documentation/config/bundle.txt b/Documentation/config/bundle.txt index daa21eb674a..3faae386853 100644 --- a/Documentation/config/bundle.txt +++ b/Documentation/config/bundle.txt @@ -15,6 +15,13 @@ bundle.mode:: complete understanding of the bundled information (`all`) or if any one of the listed bundle URIs is sufficient (`any`). +bundle.heuristic:: + If this string-valued key exists, then the bundle list is designed to + work well with incremental `git fetch` commands. The heuristic signals + that there are additional keys available for each bundle that help + determine which subset of bundles the client should download. The + only value currently understood is `creationToken`. + bundle..*:: The `bundle..*` keys are used to describe a single item in the bundle list, grouped under `` for identification purposes. diff --git a/bundle-uri.c b/bundle-uri.c index 36268dda172..36ec542718d 100644 --- a/bundle-uri.c +++ b/bundle-uri.c @@ -9,6 +9,14 @@ #include "config.h" #include "remote.h" +static struct { + enum bundle_list_heuristic heuristic; + const char *name; +} heuristics[BUNDLE_HEURISTIC__COUNT] = { + { BUNDLE_HEURISTIC_NONE, ""}, + { BUNDLE_HEURISTIC_CREATIONTOKEN, "creationToken" }, +}; + static int compare_bundles(const void *hashmap_cmp_fn_data, const struct hashmap_entry *he1, const struct hashmap_entry *he2, @@ -100,6 +108,17 @@ void print_bundle_list(FILE *fp, struct bundle_list *list) fprintf(fp, "\tversion = %d\n", list->version); fprintf(fp, "\tmode = %s\n", mode); + if (list->heuristic) { + int i; + for (i = 0; i < BUNDLE_HEURISTIC__COUNT; i++) { + if (heuristics[i].heuristic == list->heuristic) { + printf("\theuristic = %s\n", + heuristics[list->heuristic].name); + break; + } + } + } + for_all_bundles_in_list(list, summarize_bundle, fp); } @@ -142,6 +161,21 @@ static int bundle_list_update(const char *key, const char *value, return 0; } + if (!strcmp(subkey, "heuristic")) { + int i; + for (i = 0; i < BUNDLE_HEURISTIC__COUNT; i++) { + if (heuristics[i].heuristic && + heuristics[i].name && + !strcmp(value, heuristics[i].name)) { + list->heuristic = heuristics[i].heuristic; + return 0; + } + } + + /* Ignore unknown heuristics. */ + return 0; + } + /* Ignore other unknown global keys. */ return 0; } diff --git a/bundle-uri.h b/bundle-uri.h index d5e89f1671c..2e44a50a90b 100644 --- a/bundle-uri.h +++ b/bundle-uri.h @@ -52,6 +52,14 @@ enum bundle_list_mode { BUNDLE_MODE_ANY }; +enum bundle_list_heuristic { + BUNDLE_HEURISTIC_NONE = 0, + BUNDLE_HEURISTIC_CREATIONTOKEN, + + /* Must be last. */ + BUNDLE_HEURISTIC__COUNT +}; + /** * A bundle_list contains an unordered set of remote_bundle_info structs, * as well as information about the bundle listing, such as version and @@ -75,6 +83,12 @@ struct bundle_list { * advertised by the bundle list at that location. */ char *baseURI; + + /** + * A list can have a heuristic, which helps reduce the number of + * downloaded bundles. + */ + enum bundle_list_heuristic heuristic; }; void init_bundle_list(struct bundle_list *list); diff --git a/t/t5750-bundle-uri-parse.sh b/t/t5750-bundle-uri-parse.sh index 7b4f930e532..6fc92a9c0d4 100755 --- a/t/t5750-bundle-uri-parse.sh +++ b/t/t5750-bundle-uri-parse.sh @@ -250,4 +250,23 @@ test_expect_success 'parse config format edge cases: empty key or value' ' test_cmp_config_output expect actual ' +test_expect_success 'parse config format: creationToken heuristic' ' + cat >expect <<-\EOF && + [bundle] + version = 1 + mode = all + heuristic = creationToken + [bundle "one"] + uri = http://example.com/bundle.bdl + [bundle "two"] + uri = https://example.com/bundle.bdl + [bundle "three"] + uri = file:///usr/share/git/bundle.bdl + EOF + + test-tool bundle-uri parse-config expect >actual 2>err && + test_must_be_empty err && + test_cmp_config_output expect actual +' + test_done -- gitgitgadget