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-rw-r--r--builtin/name-rev.c686
1 files changed, 686 insertions, 0 deletions
diff --git a/builtin/name-rev.c b/builtin/name-rev.c
new file mode 100644
index 0000000..15535e9
--- /dev/null
+++ b/builtin/name-rev.c
@@ -0,0 +1,686 @@
+#include "builtin.h"
+#include "cache.h"
+#include "repository.h"
+#include "config.h"
+#include "commit.h"
+#include "tag.h"
+#include "refs.h"
+#include "parse-options.h"
+#include "prio-queue.h"
+#include "hash-lookup.h"
+#include "commit-slab.h"
+#include "commit-graph.h"
+
+/*
+ * One day. See the 'name a rev shortly after epoch' test in t6120 when
+ * changing this value
+ */
+#define CUTOFF_DATE_SLOP 86400
+
+struct rev_name {
+ const char *tip_name;
+ timestamp_t taggerdate;
+ int generation;
+ int distance;
+ int from_tag;
+};
+
+define_commit_slab(commit_rev_name, struct rev_name);
+
+static timestamp_t generation_cutoff = GENERATION_NUMBER_INFINITY;
+static timestamp_t cutoff = TIME_MAX;
+static struct commit_rev_name rev_names;
+
+/* Disable the cutoff checks entirely */
+static void disable_cutoff(void)
+{
+ generation_cutoff = 0;
+ cutoff = 0;
+}
+
+/* Cutoff searching any commits older than this one */
+static void set_commit_cutoff(struct commit *commit)
+{
+
+ if (cutoff > commit->date)
+ cutoff = commit->date;
+
+ if (generation_cutoff) {
+ timestamp_t generation = commit_graph_generation(commit);
+
+ if (generation_cutoff > generation)
+ generation_cutoff = generation;
+ }
+}
+
+/* adjust the commit date cutoff with a slop to allow for slightly incorrect
+ * commit timestamps in case of clock skew.
+ */
+static void adjust_cutoff_timestamp_for_slop(void)
+{
+ if (cutoff) {
+ /* check for undeflow */
+ if (cutoff > TIME_MIN + CUTOFF_DATE_SLOP)
+ cutoff = cutoff - CUTOFF_DATE_SLOP;
+ else
+ cutoff = TIME_MIN;
+ }
+}
+
+/* Check if a commit is before the cutoff. Prioritize generation numbers
+ * first, but use the commit timestamp if we lack generation data.
+ */
+static int commit_is_before_cutoff(struct commit *commit)
+{
+ if (generation_cutoff < GENERATION_NUMBER_INFINITY)
+ return generation_cutoff &&
+ commit_graph_generation(commit) < generation_cutoff;
+
+ return commit->date < cutoff;
+}
+
+/* How many generations are maximally preferred over _one_ merge traversal? */
+#define MERGE_TRAVERSAL_WEIGHT 65535
+
+static int is_valid_rev_name(const struct rev_name *name)
+{
+ return name && name->tip_name;
+}
+
+static struct rev_name *get_commit_rev_name(const struct commit *commit)
+{
+ struct rev_name *name = commit_rev_name_peek(&rev_names, commit);
+
+ return is_valid_rev_name(name) ? name : NULL;
+}
+
+static int effective_distance(int distance, int generation)
+{
+ return distance + (generation > 0 ? MERGE_TRAVERSAL_WEIGHT : 0);
+}
+
+static int is_better_name(struct rev_name *name,
+ timestamp_t taggerdate,
+ int generation,
+ int distance,
+ int from_tag)
+{
+ int name_distance = effective_distance(name->distance, name->generation);
+ int new_distance = effective_distance(distance, generation);
+
+ /*
+ * When comparing names based on tags, prefer names
+ * based on the older tag, even if it is farther away.
+ */
+ if (from_tag && name->from_tag)
+ return (name->taggerdate > taggerdate ||
+ (name->taggerdate == taggerdate &&
+ name_distance > new_distance));
+
+ /*
+ * We know that at least one of them is a non-tag at this point.
+ * favor a tag over a non-tag.
+ */
+ if (name->from_tag != from_tag)
+ return from_tag;
+
+ /*
+ * We are now looking at two non-tags. Tiebreak to favor
+ * shorter hops.
+ */
+ if (name_distance != new_distance)
+ return name_distance > new_distance;
+
+ /* ... or tiebreak to favor older date */
+ if (name->taggerdate != taggerdate)
+ return name->taggerdate > taggerdate;
+
+ /* keep the current one if we cannot decide */
+ return 0;
+}
+
+static struct rev_name *create_or_update_name(struct commit *commit,
+ timestamp_t taggerdate,
+ int generation, int distance,
+ int from_tag)
+{
+ struct rev_name *name = commit_rev_name_at(&rev_names, commit);
+
+ if (is_valid_rev_name(name) &&
+ !is_better_name(name, taggerdate, generation, distance, from_tag))
+ return NULL;
+
+ name->taggerdate = taggerdate;
+ name->generation = generation;
+ name->distance = distance;
+ name->from_tag = from_tag;
+
+ return name;
+}
+
+static char *get_parent_name(const struct rev_name *name, int parent_number)
+{
+ struct strbuf sb = STRBUF_INIT;
+ size_t len;
+
+ strip_suffix(name->tip_name, "^0", &len);
+ if (name->generation > 0) {
+ strbuf_grow(&sb, len +
+ 1 + decimal_width(name->generation) +
+ 1 + decimal_width(parent_number));
+ strbuf_addf(&sb, "%.*s~%d^%d", (int)len, name->tip_name,
+ name->generation, parent_number);
+ } else {
+ strbuf_grow(&sb, len +
+ 1 + decimal_width(parent_number));
+ strbuf_addf(&sb, "%.*s^%d", (int)len, name->tip_name,
+ parent_number);
+ }
+ return strbuf_detach(&sb, NULL);
+}
+
+static void name_rev(struct commit *start_commit,
+ const char *tip_name, timestamp_t taggerdate,
+ int from_tag, int deref)
+{
+ struct prio_queue queue;
+ struct commit *commit;
+ struct commit **parents_to_queue = NULL;
+ size_t parents_to_queue_nr, parents_to_queue_alloc = 0;
+ struct rev_name *start_name;
+
+ parse_commit(start_commit);
+ if (commit_is_before_cutoff(start_commit))
+ return;
+
+ start_name = create_or_update_name(start_commit, taggerdate, 0, 0,
+ from_tag);
+ if (!start_name)
+ return;
+ if (deref)
+ start_name->tip_name = xstrfmt("%s^0", tip_name);
+ else
+ start_name->tip_name = xstrdup(tip_name);
+
+ memset(&queue, 0, sizeof(queue)); /* Use the prio_queue as LIFO */
+ prio_queue_put(&queue, start_commit);
+
+ while ((commit = prio_queue_get(&queue))) {
+ struct rev_name *name = get_commit_rev_name(commit);
+ struct commit_list *parents;
+ int parent_number = 1;
+
+ parents_to_queue_nr = 0;
+
+ for (parents = commit->parents;
+ parents;
+ parents = parents->next, parent_number++) {
+ struct commit *parent = parents->item;
+ struct rev_name *parent_name;
+ int generation, distance;
+
+ parse_commit(parent);
+ if (commit_is_before_cutoff(parent))
+ continue;
+
+ if (parent_number > 1) {
+ generation = 0;
+ distance = name->distance + MERGE_TRAVERSAL_WEIGHT;
+ } else {
+ generation = name->generation + 1;
+ distance = name->distance + 1;
+ }
+
+ parent_name = create_or_update_name(parent, taggerdate,
+ generation,
+ distance, from_tag);
+ if (parent_name) {
+ if (parent_number > 1)
+ parent_name->tip_name =
+ get_parent_name(name,
+ parent_number);
+ else
+ parent_name->tip_name = name->tip_name;
+ ALLOC_GROW(parents_to_queue,
+ parents_to_queue_nr + 1,
+ parents_to_queue_alloc);
+ parents_to_queue[parents_to_queue_nr] = parent;
+ parents_to_queue_nr++;
+ }
+ }
+
+ /* The first parent must come out first from the prio_queue */
+ while (parents_to_queue_nr)
+ prio_queue_put(&queue,
+ parents_to_queue[--parents_to_queue_nr]);
+ }
+
+ clear_prio_queue(&queue);
+ free(parents_to_queue);
+}
+
+static int subpath_matches(const char *path, const char *filter)
+{
+ const char *subpath = path;
+
+ while (subpath) {
+ if (!wildmatch(filter, subpath, 0))
+ return subpath - path;
+ subpath = strchr(subpath, '/');
+ if (subpath)
+ subpath++;
+ }
+ return -1;
+}
+
+static const char *name_ref_abbrev(const char *refname, int shorten_unambiguous)
+{
+ if (shorten_unambiguous)
+ refname = shorten_unambiguous_ref(refname, 0);
+ else if (skip_prefix(refname, "refs/heads/", &refname))
+ ; /* refname already advanced */
+ else
+ skip_prefix(refname, "refs/", &refname);
+ return refname;
+}
+
+struct name_ref_data {
+ int tags_only;
+ int name_only;
+ struct string_list ref_filters;
+ struct string_list exclude_filters;
+};
+
+static struct tip_table {
+ struct tip_table_entry {
+ struct object_id oid;
+ const char *refname;
+ struct commit *commit;
+ timestamp_t taggerdate;
+ unsigned int from_tag:1;
+ unsigned int deref:1;
+ } *table;
+ int nr;
+ int alloc;
+ int sorted;
+} tip_table;
+
+static void add_to_tip_table(const struct object_id *oid, const char *refname,
+ int shorten_unambiguous, struct commit *commit,
+ timestamp_t taggerdate, int from_tag, int deref)
+{
+ refname = name_ref_abbrev(refname, shorten_unambiguous);
+
+ ALLOC_GROW(tip_table.table, tip_table.nr + 1, tip_table.alloc);
+ oidcpy(&tip_table.table[tip_table.nr].oid, oid);
+ tip_table.table[tip_table.nr].refname = xstrdup(refname);
+ tip_table.table[tip_table.nr].commit = commit;
+ tip_table.table[tip_table.nr].taggerdate = taggerdate;
+ tip_table.table[tip_table.nr].from_tag = from_tag;
+ tip_table.table[tip_table.nr].deref = deref;
+ tip_table.nr++;
+ tip_table.sorted = 0;
+}
+
+static int tipcmp(const void *a_, const void *b_)
+{
+ const struct tip_table_entry *a = a_, *b = b_;
+ return oidcmp(&a->oid, &b->oid);
+}
+
+static int cmp_by_tag_and_age(const void *a_, const void *b_)
+{
+ const struct tip_table_entry *a = a_, *b = b_;
+ int cmp;
+
+ /* Prefer tags. */
+ cmp = b->from_tag - a->from_tag;
+ if (cmp)
+ return cmp;
+
+ /* Older is better. */
+ if (a->taggerdate < b->taggerdate)
+ return -1;
+ return a->taggerdate != b->taggerdate;
+}
+
+static int name_ref(const char *path, const struct object_id *oid,
+ int flags UNUSED, void *cb_data)
+{
+ struct object *o = parse_object(the_repository, oid);
+ struct name_ref_data *data = cb_data;
+ int can_abbreviate_output = data->tags_only && data->name_only;
+ int deref = 0;
+ int from_tag = 0;
+ struct commit *commit = NULL;
+ timestamp_t taggerdate = TIME_MAX;
+
+ if (data->tags_only && !starts_with(path, "refs/tags/"))
+ return 0;
+
+ if (data->exclude_filters.nr) {
+ struct string_list_item *item;
+
+ for_each_string_list_item(item, &data->exclude_filters) {
+ if (subpath_matches(path, item->string) >= 0)
+ return 0;
+ }
+ }
+
+ if (data->ref_filters.nr) {
+ struct string_list_item *item;
+ int matched = 0;
+
+ /* See if any of the patterns match. */
+ for_each_string_list_item(item, &data->ref_filters) {
+ /*
+ * Check all patterns even after finding a match, so
+ * that we can see if a match with a subpath exists.
+ * When a user asked for 'refs/tags/v*' and 'v1.*',
+ * both of which match, the user is showing her
+ * willingness to accept a shortened output by having
+ * the 'v1.*' in the acceptable refnames, so we
+ * shouldn't stop when seeing 'refs/tags/v1.4' matches
+ * 'refs/tags/v*'. We should show it as 'v1.4'.
+ */
+ switch (subpath_matches(path, item->string)) {
+ case -1: /* did not match */
+ break;
+ case 0: /* matched fully */
+ matched = 1;
+ break;
+ default: /* matched subpath */
+ matched = 1;
+ can_abbreviate_output = 1;
+ break;
+ }
+ }
+
+ /* If none of the patterns matched, stop now */
+ if (!matched)
+ return 0;
+ }
+
+ while (o && o->type == OBJ_TAG) {
+ struct tag *t = (struct tag *) o;
+ if (!t->tagged)
+ break; /* broken repository */
+ o = parse_object(the_repository, &t->tagged->oid);
+ deref = 1;
+ taggerdate = t->date;
+ }
+ if (o && o->type == OBJ_COMMIT) {
+ commit = (struct commit *)o;
+ from_tag = starts_with(path, "refs/tags/");
+ if (taggerdate == TIME_MAX)
+ taggerdate = commit->date;
+ }
+
+ add_to_tip_table(oid, path, can_abbreviate_output, commit, taggerdate,
+ from_tag, deref);
+ return 0;
+}
+
+static void name_tips(void)
+{
+ int i;
+
+ /*
+ * Try to set better names first, so that worse ones spread
+ * less.
+ */
+ QSORT(tip_table.table, tip_table.nr, cmp_by_tag_and_age);
+ for (i = 0; i < tip_table.nr; i++) {
+ struct tip_table_entry *e = &tip_table.table[i];
+ if (e->commit) {
+ name_rev(e->commit, e->refname, e->taggerdate,
+ e->from_tag, e->deref);
+ }
+ }
+}
+
+static const struct object_id *nth_tip_table_ent(size_t ix, const void *table_)
+{
+ const struct tip_table_entry *table = table_;
+ return &table[ix].oid;
+}
+
+static const char *get_exact_ref_match(const struct object *o)
+{
+ int found;
+
+ if (!tip_table.table || !tip_table.nr)
+ return NULL;
+
+ if (!tip_table.sorted) {
+ QSORT(tip_table.table, tip_table.nr, tipcmp);
+ tip_table.sorted = 1;
+ }
+
+ found = oid_pos(&o->oid, tip_table.table, tip_table.nr,
+ nth_tip_table_ent);
+ if (0 <= found)
+ return tip_table.table[found].refname;
+ return NULL;
+}
+
+/* may return a constant string or use "buf" as scratch space */
+static const char *get_rev_name(const struct object *o, struct strbuf *buf)
+{
+ struct rev_name *n;
+ const struct commit *c;
+
+ if (o->type != OBJ_COMMIT)
+ return get_exact_ref_match(o);
+ c = (const struct commit *) o;
+ n = get_commit_rev_name(c);
+ if (!n)
+ return NULL;
+
+ if (!n->generation)
+ return n->tip_name;
+ else {
+ strbuf_reset(buf);
+ strbuf_addstr(buf, n->tip_name);
+ strbuf_strip_suffix(buf, "^0");
+ strbuf_addf(buf, "~%d", n->generation);
+ return buf->buf;
+ }
+}
+
+static void show_name(const struct object *obj,
+ const char *caller_name,
+ int always, int allow_undefined, int name_only)
+{
+ const char *name;
+ const struct object_id *oid = &obj->oid;
+ struct strbuf buf = STRBUF_INIT;
+
+ if (!name_only)
+ printf("%s ", caller_name ? caller_name : oid_to_hex(oid));
+ name = get_rev_name(obj, &buf);
+ if (name)
+ printf("%s\n", name);
+ else if (allow_undefined)
+ printf("undefined\n");
+ else if (always)
+ printf("%s\n", find_unique_abbrev(oid, DEFAULT_ABBREV));
+ else
+ die("cannot describe '%s'", oid_to_hex(oid));
+ strbuf_release(&buf);
+}
+
+static char const * const name_rev_usage[] = {
+ N_("git name-rev [<options>] <commit>..."),
+ N_("git name-rev [<options>] --all"),
+ N_("git name-rev [<options>] --annotate-stdin"),
+ NULL
+};
+
+static void name_rev_line(char *p, struct name_ref_data *data)
+{
+ struct strbuf buf = STRBUF_INIT;
+ int counter = 0;
+ char *p_start;
+ const unsigned hexsz = the_hash_algo->hexsz;
+
+ for (p_start = p; *p; p++) {
+#define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
+ if (!ishex(*p))
+ counter = 0;
+ else if (++counter == hexsz &&
+ !ishex(*(p+1))) {
+ struct object_id oid;
+ const char *name = NULL;
+ char c = *(p+1);
+ int p_len = p - p_start + 1;
+
+ counter = 0;
+
+ *(p+1) = 0;
+ if (!get_oid(p - (hexsz - 1), &oid)) {
+ struct object *o =
+ lookup_object(the_repository, &oid);
+ if (o)
+ name = get_rev_name(o, &buf);
+ }
+ *(p+1) = c;
+
+ if (!name)
+ continue;
+
+ if (data->name_only)
+ printf("%.*s%s", p_len - hexsz, p_start, name);
+ else
+ printf("%.*s (%s)", p_len, p_start, name);
+ p_start = p + 1;
+ }
+ }
+
+ /* flush */
+ if (p_start != p)
+ fwrite(p_start, p - p_start, 1, stdout);
+
+ strbuf_release(&buf);
+}
+
+int cmd_name_rev(int argc, const char **argv, const char *prefix)
+{
+ struct object_array revs = OBJECT_ARRAY_INIT;
+ int all = 0, annotate_stdin = 0, transform_stdin = 0, allow_undefined = 1, always = 0, peel_tag = 0;
+ struct name_ref_data data = { 0, 0, STRING_LIST_INIT_NODUP, STRING_LIST_INIT_NODUP };
+ struct option opts[] = {
+ OPT_BOOL(0, "name-only", &data.name_only, N_("print only ref-based names (no object names)")),
+ OPT_BOOL(0, "tags", &data.tags_only, N_("only use tags to name the commits")),
+ OPT_STRING_LIST(0, "refs", &data.ref_filters, N_("pattern"),
+ N_("only use refs matching <pattern>")),
+ OPT_STRING_LIST(0, "exclude", &data.exclude_filters, N_("pattern"),
+ N_("ignore refs matching <pattern>")),
+ OPT_GROUP(""),
+ OPT_BOOL(0, "all", &all, N_("list all commits reachable from all refs")),
+ OPT_BOOL(0, "stdin", &transform_stdin, N_("deprecated: use --annotate-stdin instead")),
+ OPT_BOOL(0, "annotate-stdin", &annotate_stdin, N_("annotate text from stdin")),
+ OPT_BOOL(0, "undefined", &allow_undefined, N_("allow to print `undefined` names (default)")),
+ OPT_BOOL(0, "always", &always,
+ N_("show abbreviated commit object as fallback")),
+ {
+ /* A Hidden OPT_BOOL */
+ OPTION_SET_INT, 0, "peel-tag", &peel_tag, NULL,
+ N_("dereference tags in the input (internal use)"),
+ PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1,
+ },
+ OPT_END(),
+ };
+
+ init_commit_rev_name(&rev_names);
+ git_config(git_default_config, NULL);
+ argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
+
+ if (transform_stdin) {
+ warning("--stdin is deprecated. Please use --annotate-stdin instead, "
+ "which is functionally equivalent.\n"
+ "This option will be removed in a future release.");
+ annotate_stdin = 1;
+ }
+
+ if (all + annotate_stdin + !!argc > 1) {
+ error("Specify either a list, or --all, not both!");
+ usage_with_options(name_rev_usage, opts);
+ }
+ if (all || annotate_stdin)
+ disable_cutoff();
+
+ for (; argc; argc--, argv++) {
+ struct object_id oid;
+ struct object *object;
+ struct commit *commit;
+
+ if (get_oid(*argv, &oid)) {
+ fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
+ *argv);
+ continue;
+ }
+
+ commit = NULL;
+ object = parse_object(the_repository, &oid);
+ if (object) {
+ struct object *peeled = deref_tag(the_repository,
+ object, *argv, 0);
+ if (peeled && peeled->type == OBJ_COMMIT)
+ commit = (struct commit *)peeled;
+ }
+
+ if (!object) {
+ fprintf(stderr, "Could not get object for %s. Skipping.\n",
+ *argv);
+ continue;
+ }
+
+ if (commit)
+ set_commit_cutoff(commit);
+
+ if (peel_tag) {
+ if (!commit) {
+ fprintf(stderr, "Could not get commit for %s. Skipping.\n",
+ *argv);
+ continue;
+ }
+ object = (struct object *)commit;
+ }
+ add_object_array(object, *argv, &revs);
+ }
+
+ adjust_cutoff_timestamp_for_slop();
+
+ for_each_ref(name_ref, &data);
+ name_tips();
+
+ if (annotate_stdin) {
+ struct strbuf sb = STRBUF_INIT;
+
+ while (strbuf_getline(&sb, stdin) != EOF) {
+ strbuf_addch(&sb, '\n');
+ name_rev_line(sb.buf, &data);
+ }
+ strbuf_release(&sb);
+ } else if (all) {
+ int i, max;
+
+ max = get_max_object_index();
+ for (i = 0; i < max; i++) {
+ struct object *obj = get_indexed_object(i);
+ if (!obj || obj->type != OBJ_COMMIT)
+ continue;
+ show_name(obj, NULL,
+ always, allow_undefined, data.name_only);
+ }
+ } else {
+ int i;
+ for (i = 0; i < revs.nr; i++)
+ show_name(revs.objects[i].item, revs.objects[i].name,
+ always, allow_undefined, data.name_only);
+ }
+
+ UNLEAK(revs);
+ return 0;
+}