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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 12:47:08 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 12:47:08 +0000
commit29b5ab554790bb57337a3b6ab9dcd963cf69d22e (patch)
treebe1456d2bc6c1fb078695fad7bc8f6b212062d3c /examples/describe.c
parentInitial commit. (diff)
downloadlibgit2-29b5ab554790bb57337a3b6ab9dcd963cf69d22e.tar.xz
libgit2-29b5ab554790bb57337a3b6ab9dcd963cf69d22e.zip
Adding upstream version 1.7.2+ds.upstream/1.7.2+ds
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+/*
+ * libgit2 "describe" example - shows how to describe commits
+ *
+ * Written by the libgit2 contributors
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along
+ * with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
+ */
+
+#include "common.h"
+
+/**
+ * The following example partially reimplements the `git describe` command
+ * and some of its options.
+ *
+ * These commands should work:
+
+ * - Describe HEAD with default options (`describe`)
+ * - Describe specified revision (`describe master~2`)
+ * - Describe specified revisions (`describe master~2 HEAD~3`)
+ * - Describe HEAD with dirty state suffix (`describe --dirty=*`)
+ * - Describe consider all refs (`describe --all master`)
+ * - Describe consider lightweight tags (`describe --tags temp-tag`)
+ * - Describe show non-default abbreviated size (`describe --abbrev=10`)
+ * - Describe always output the long format if matches a tag (`describe --long v1.0`)
+ * - Describe consider only tags of specified pattern (`describe --match v*-release`)
+ * - Describe show the fallback result (`describe --always`)
+ * - Describe follow only the first parent commit (`describe --first-parent`)
+ *
+ * The command line parsing logic is simplified and doesn't handle
+ * all of the use cases.
+ */
+
+/** describe_options represents the parsed command line options */
+struct describe_options {
+ const char **commits;
+ size_t commit_count;
+ git_describe_options describe_options;
+ git_describe_format_options format_options;
+};
+
+static void opts_add_commit(struct describe_options *opts, const char *commit)
+{
+ size_t sz;
+
+ assert(opts != NULL);
+
+ sz = ++opts->commit_count * sizeof(opts->commits[0]);
+ opts->commits = xrealloc((void *) opts->commits, sz);
+ opts->commits[opts->commit_count - 1] = commit;
+}
+
+static void do_describe_single(git_repository *repo, struct describe_options *opts, const char *rev)
+{
+ git_object *commit;
+ git_describe_result *describe_result;
+ git_buf buf = { 0 };
+
+ if (rev) {
+ check_lg2(git_revparse_single(&commit, repo, rev),
+ "Failed to lookup rev", rev);
+
+ check_lg2(git_describe_commit(&describe_result, commit, &opts->describe_options),
+ "Failed to describe rev", rev);
+ }
+ else
+ check_lg2(git_describe_workdir(&describe_result, repo, &opts->describe_options),
+ "Failed to describe workdir", NULL);
+
+ check_lg2(git_describe_format(&buf, describe_result, &opts->format_options),
+ "Failed to format describe rev", rev);
+
+ printf("%s\n", buf.ptr);
+}
+
+static void do_describe(git_repository *repo, struct describe_options *opts)
+{
+ if (opts->commit_count == 0)
+ do_describe_single(repo, opts, NULL);
+ else
+ {
+ size_t i;
+ for (i = 0; i < opts->commit_count; i++)
+ do_describe_single(repo, opts, opts->commits[i]);
+ }
+}
+
+static void print_usage(void)
+{
+ fprintf(stderr, "usage: see `git help describe`\n");
+ exit(1);
+}
+
+/** Parse command line arguments */
+static void parse_options(struct describe_options *opts, int argc, char **argv)
+{
+ struct args_info args = ARGS_INFO_INIT;
+
+ for (args.pos = 1; args.pos < argc; ++args.pos) {
+ const char *curr = argv[args.pos];
+
+ if (curr[0] != '-') {
+ opts_add_commit(opts, curr);
+ } else if (!strcmp(curr, "--all")) {
+ opts->describe_options.describe_strategy = GIT_DESCRIBE_ALL;
+ } else if (!strcmp(curr, "--tags")) {
+ opts->describe_options.describe_strategy = GIT_DESCRIBE_TAGS;
+ } else if (!strcmp(curr, "--exact-match")) {
+ opts->describe_options.max_candidates_tags = 0;
+ } else if (!strcmp(curr, "--long")) {
+ opts->format_options.always_use_long_format = 1;
+ } else if (!strcmp(curr, "--always")) {
+ opts->describe_options.show_commit_oid_as_fallback = 1;
+ } else if (!strcmp(curr, "--first-parent")) {
+ opts->describe_options.only_follow_first_parent = 1;
+ } else if (optional_str_arg(&opts->format_options.dirty_suffix, &args, "--dirty", "-dirty")) {
+ } else if (match_int_arg((int *)&opts->format_options.abbreviated_size, &args, "--abbrev", 0)) {
+ } else if (match_int_arg((int *)&opts->describe_options.max_candidates_tags, &args, "--candidates", 0)) {
+ } else if (match_str_arg(&opts->describe_options.pattern, &args, "--match")) {
+ } else {
+ print_usage();
+ }
+ }
+
+ if (opts->commit_count > 0) {
+ if (opts->format_options.dirty_suffix)
+ fatal("--dirty is incompatible with commit-ishes", NULL);
+ }
+ else {
+ if (!opts->format_options.dirty_suffix || !opts->format_options.dirty_suffix[0]) {
+ opts_add_commit(opts, "HEAD");
+ }
+ }
+}
+
+/** Initialize describe_options struct */
+static void describe_options_init(struct describe_options *opts)
+{
+ memset(opts, 0, sizeof(*opts));
+
+ opts->commits = NULL;
+ opts->commit_count = 0;
+ git_describe_options_init(&opts->describe_options, GIT_DESCRIBE_OPTIONS_VERSION);
+ git_describe_format_options_init(&opts->format_options, GIT_DESCRIBE_FORMAT_OPTIONS_VERSION);
+}
+
+int lg2_describe(git_repository *repo, int argc, char **argv)
+{
+ struct describe_options opts;
+
+ describe_options_init(&opts);
+ parse_options(&opts, argc, argv);
+
+ do_describe(repo, &opts);
+
+ return 0;
+}