Adding upstream version 1:2.45.1.upstream/1%2.45.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 205 insertions, 62 deletions

diff --git a/refs.c b/refs.c
index fcae5dd..55d2e0b 100644
--- a/refs.c
+++ b/refs.c
@@ -33,17 +33,34 @@
 /*
  * List of all available backends
  */
-static struct ref_storage_be *refs_backends = &refs_be_files;
+static const struct ref_storage_be *refs_backends[] = {
+	[REF_STORAGE_FORMAT_FILES] = &refs_be_files,
+	[REF_STORAGE_FORMAT_REFTABLE] = &refs_be_reftable,
+};
 
-static struct ref_storage_be *find_ref_storage_backend(const char *name)
+static const struct ref_storage_be *find_ref_storage_backend(unsigned int ref_storage_format)
 {
-	struct ref_storage_be *be;
-	for (be = refs_backends; be; be = be->next)
-		if (!strcmp(be->name, name))
-			return be;
+	if (ref_storage_format < ARRAY_SIZE(refs_backends))
+		return refs_backends[ref_storage_format];
 	return NULL;
 }
 
+unsigned int ref_storage_format_by_name(const char *name)
+{
+	for (unsigned int i = 0; i < ARRAY_SIZE(refs_backends); i++)
+		if (refs_backends[i] && !strcmp(refs_backends[i]->name, name))
+			return i;
+	return REF_STORAGE_FORMAT_UNKNOWN;
+}
+
+const char *ref_storage_format_to_name(unsigned int ref_storage_format)
+{
+	const struct ref_storage_be *be = find_ref_storage_backend(ref_storage_format);
+	if (!be)
+		return "unknown";
+	return be->name;
+}
+
 /*
  * How to handle various characters in refnames:
  * 0: An acceptable character for refs
@@ -843,6 +860,47 @@ static int is_pseudoref_syntax(const char *refname)
 	return 1;
 }
 
+int is_pseudoref(struct ref_store *refs, const char *refname)
+{
+	static const char *const irregular_pseudorefs[] = {
+		"AUTO_MERGE",
+		"BISECT_EXPECTED_REV",
+		"NOTES_MERGE_PARTIAL",
+		"NOTES_MERGE_REF",
+		"MERGE_AUTOSTASH",
+	};
+	struct object_id oid;
+	size_t i;
+
+	if (!is_pseudoref_syntax(refname))
+		return 0;
+
+	if (ends_with(refname, "_HEAD")) {
+		refs_resolve_ref_unsafe(refs, refname,
+					RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
+					&oid, NULL);
+		return !is_null_oid(&oid);
+	}
+
+	for (i = 0; i < ARRAY_SIZE(irregular_pseudorefs); i++)
+		if (!strcmp(refname, irregular_pseudorefs[i])) {
+			refs_resolve_ref_unsafe(refs, refname,
+						RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
+						&oid, NULL);
+			return !is_null_oid(&oid);
+		}
+
+	return 0;
+}
+
+int is_headref(struct ref_store *refs, const char *refname)
+{
+	if (!strcmp(refname, "HEAD"))
+		return refs_ref_exists(refs, refname);
+
+	return 0;
+}
+
 static int is_current_worktree_ref(const char *ref) {
 	return is_pseudoref_syntax(ref) || is_per_worktree_ref(ref);
 }
@@ -1022,55 +1080,40 @@ static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
 			   const char *message, void *cb_data)
 {
 	struct read_ref_at_cb *cb = cb_data;
-	int reached_count;
 
 	cb->tz = tz;
 	cb->date = timestamp;
 
-	/*
-	 * It is not possible for cb->cnt == 0 on the first iteration because
-	 * that special case is handled in read_ref_at().
-	 */
-	if (cb->cnt > 0)
-		cb->cnt--;
-	reached_count = cb->cnt == 0 && !is_null_oid(ooid);
-	if (timestamp <= cb->at_time || reached_count) {
+	if (timestamp <= cb->at_time || cb->cnt == 0) {
 		set_read_ref_cutoffs(cb, timestamp, tz, message);
 		/*
 		 * we have not yet updated cb->[n|o]oid so they still
 		 * hold the values for the previous record.
 		 */
-		if (!is_null_oid(&cb->ooid) && !oideq(&cb->ooid, noid))
-			warning(_("log for ref %s has gap after %s"),
+		if (!is_null_oid(&cb->ooid)) {
+			oidcpy(cb->oid, noid);
+			if (!oideq(&cb->ooid, noid))
+				warning(_("log for ref %s has gap after %s"),
 					cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
-		if (reached_count)
-			oidcpy(cb->oid, ooid);
-		else if (!is_null_oid(&cb->ooid) || cb->date == cb->at_time)
+		}
+		else if (cb->date == cb->at_time)
 			oidcpy(cb->oid, noid);
 		else if (!oideq(noid, cb->oid))
 			warning(_("log for ref %s unexpectedly ended on %s"),
 				cb->refname, show_date(cb->date, cb->tz,
 						       DATE_MODE(RFC2822)));
+		cb->reccnt++;
+		oidcpy(&cb->ooid, ooid);
+		oidcpy(&cb->noid, noid);
 		cb->found_it = 1;
+		return 1;
 	}
 	cb->reccnt++;
 	oidcpy(&cb->ooid, ooid);
 	oidcpy(&cb->noid, noid);
-	return cb->found_it;
-}
-
-static int read_ref_at_ent_newest(struct object_id *ooid UNUSED,
-				  struct object_id *noid,
-				  const char *email UNUSED,
-				  timestamp_t timestamp, int tz,
-				  const char *message, void *cb_data)
-{
-	struct read_ref_at_cb *cb = cb_data;
-
-	set_read_ref_cutoffs(cb, timestamp, tz, message);
-	oidcpy(cb->oid, noid);
-	/* We just want the first entry */
-	return 1;
+	if (cb->cnt > 0)
+		cb->cnt--;
+	return 0;
 }
 
 static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
@@ -1082,7 +1125,7 @@ static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid
 
 	set_read_ref_cutoffs(cb, timestamp, tz, message);
 	oidcpy(cb->oid, ooid);
-	if (is_null_oid(cb->oid))
+	if (cb->at_time && is_null_oid(cb->oid))
 		oidcpy(cb->oid, noid);
 	/* We just want the first entry */
 	return 1;
@@ -1105,14 +1148,24 @@ int read_ref_at(struct ref_store *refs, const char *refname,
 	cb.cutoff_cnt = cutoff_cnt;
 	cb.oid = oid;
 
-	if (cb.cnt == 0) {
-		refs_for_each_reflog_ent_reverse(refs, refname, read_ref_at_ent_newest, &cb);
-		return 0;
-	}
-
 	refs_for_each_reflog_ent_reverse(refs, refname, read_ref_at_ent, &cb);
 
 	if (!cb.reccnt) {
+		if (cnt == 0) {
+			/*
+			 * The caller asked for ref@{0}, and we had no entries.
+			 * It's a bit subtle, but in practice all callers have
+			 * prepped the "oid" field with the current value of
+			 * the ref, which is the most reasonable fallback.
+			 *
+			 * We'll put dummy values into the out-parameters (so
+			 * they're not just uninitialized garbage), and the
+			 * caller can take our return value as a hint that
+			 * we did not find any such reflog.
+			 */
+			set_read_ref_cutoffs(&cb, 0, 0, "empty reflog");
+			return 1;
+		}
 		if (flags & GET_OID_QUIETLY)
 			exit(128);
 		else
@@ -1577,10 +1630,6 @@ struct ref_iterator *refs_ref_iterator_begin(
 	if (trim)
 		iter = prefix_ref_iterator_begin(iter, "", trim);
 
-	/* Sanity check for subclasses: */
-	if (!iter->ordered)
-		BUG("reference iterator is not ordered");
-
 	return iter;
 }
 
@@ -1707,6 +1756,13 @@ int for_each_rawref(each_ref_fn fn, void *cb_data)
 	return refs_for_each_rawref(get_main_ref_store(the_repository), fn, cb_data);
 }
 
+int refs_for_each_include_root_refs(struct ref_store *refs, each_ref_fn fn,
+				    void *cb_data)
+{
+	return do_for_each_ref(refs, "", NULL, fn, 0,
+			       DO_FOR_EACH_INCLUDE_ROOT_REFS, cb_data);
+}
+
 static int qsort_strcmp(const void *va, const void *vb)
 {
 	const char *a = *(const char **)va;
@@ -1806,8 +1862,10 @@ static int refs_read_special_head(struct ref_store *ref_store,
 	int result = -1;
 	strbuf_addf(&full_path, "%s/%s", ref_store->gitdir, refname);
 
-	if (strbuf_read_file(&content, full_path.buf, 0) < 0)
+	if (strbuf_read_file(&content, full_path.buf, 0) < 0) {
+		*failure_errno = errno;
 		goto done;
+	}
 
 	result = parse_loose_ref_contents(content.buf, oid, referent, type,
 					  failure_errno);
@@ -1818,15 +1876,45 @@ done:
 	return result;
 }
 
+static int is_special_ref(const char *refname)
+{
+	/*
+	 * Special references are refs that have different semantics compared
+	 * to "normal" refs. These refs can thus not be stored in the ref
+	 * backend, but must always be accessed via the filesystem. The
+	 * following refs are special:
+	 *
+	 * - FETCH_HEAD may contain multiple object IDs, and each one of them
+	 *   carries additional metadata like where it came from.
+	 *
+	 * - MERGE_HEAD may contain multiple object IDs when merging multiple
+	 *   heads.
+	 *
+	 * Reading, writing or deleting references must consistently go either
+	 * through the filesystem (special refs) or through the reference
+	 * backend (normal ones).
+	 */
+	static const char * const special_refs[] = {
+		"FETCH_HEAD",
+		"MERGE_HEAD",
+	};
+	size_t i;
+
+	for (i = 0; i < ARRAY_SIZE(special_refs); i++)
+		if (!strcmp(refname, special_refs[i]))
+			return 1;
+
+	return 0;
+}
+
 int refs_read_raw_ref(struct ref_store *ref_store, const char *refname,
 		      struct object_id *oid, struct strbuf *referent,
 		      unsigned int *type, int *failure_errno)
 {
 	assert(failure_errno);
-	if (!strcmp(refname, "FETCH_HEAD") || !strcmp(refname, "MERGE_HEAD")) {
+	if (is_special_ref(refname))
 		return refs_read_special_head(ref_store, refname, oid, referent,
 					      type, failure_errno);
-	}
 
 	return ref_store->be->read_raw_ref(ref_store, refname, oid, referent,
 					   type, failure_errno);
@@ -1928,11 +2016,9 @@ const char *refs_resolve_ref_unsafe(struct ref_store *refs,
 }
 
 /* backend functions */
-int refs_init_db(struct strbuf *err)
+int refs_init_db(struct ref_store *refs, int flags, struct strbuf *err)
 {
-	struct ref_store *refs = get_main_ref_store(the_repository);
-
-	return refs->be->init_db(refs, err);
+	return refs->be->init_db(refs, flags, err);
 }
 
 const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
@@ -2029,12 +2115,12 @@ static struct ref_store *ref_store_init(struct repository *repo,
 					const char *gitdir,
 					unsigned int flags)
 {
-	const char *be_name = "files";
-	struct ref_storage_be *be = find_ref_storage_backend(be_name);
+	const struct ref_storage_be *be;
 	struct ref_store *refs;
 
+	be = find_ref_storage_backend(repo->ref_storage_format);
 	if (!be)
-		BUG("reference backend %s is unknown", be_name);
+		BUG("reference backend is unknown");
 
 	refs = be->init(repo, gitdir, flags);
 	return refs;
@@ -2469,18 +2555,33 @@ cleanup:
 	return ret;
 }
 
-int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)
+struct do_for_each_reflog_help {
+	each_reflog_fn *fn;
+	void *cb_data;
+};
+
+static int do_for_each_reflog_helper(struct repository *r UNUSED,
+				     const char *refname,
+				     const struct object_id *oid UNUSED,
+				     int flags,
+				     void *cb_data)
+{
+	struct do_for_each_reflog_help *hp = cb_data;
+	return hp->fn(refname, hp->cb_data);
+}
+
+int refs_for_each_reflog(struct ref_store *refs, each_reflog_fn fn, void *cb_data)
 {
 	struct ref_iterator *iter;
-	struct do_for_each_ref_help hp = { fn, cb_data };
+	struct do_for_each_reflog_help hp = { fn, cb_data };
 
 	iter = refs->be->reflog_iterator_begin(refs);
 
 	return do_for_each_repo_ref_iterator(the_repository, iter,
-					     do_for_each_ref_helper, &hp);
+					     do_for_each_reflog_helper, &hp);
 }
 
-int for_each_reflog(each_ref_fn fn, void *cb_data)
+int for_each_reflog(each_reflog_fn fn, void *cb_data)
 {
 	return refs_for_each_reflog(get_main_ref_store(the_repository), fn, cb_data);
 }
@@ -2599,13 +2700,55 @@ void ref_transaction_for_each_queued_update(struct ref_transaction *transaction,
 int refs_delete_refs(struct ref_store *refs, const char *logmsg,
 		     struct string_list *refnames, unsigned int flags)
 {
+	struct ref_transaction *transaction;
+	struct strbuf err = STRBUF_INIT;
+	struct string_list_item *item;
+	int ret = 0, failures = 0;
 	char *msg;
-	int retval;
+
+	if (!refnames->nr)
+		return 0;
 
 	msg = normalize_reflog_message(logmsg);
-	retval = refs->be->delete_refs(refs, msg, refnames, flags);
+
+	/*
+	 * Since we don't check the references' old_oids, the
+	 * individual updates can't fail, so we can pack all of the
+	 * updates into a single transaction.
+	 */
+	transaction = ref_store_transaction_begin(refs, &err);
+	if (!transaction) {
+		ret = error("%s", err.buf);
+		goto out;
+	}
+
+	for_each_string_list_item(item, refnames) {
+		ret = ref_transaction_delete(transaction, item->string,
+					     NULL, flags, msg, &err);
+		if (ret) {
+			warning(_("could not delete reference %s: %s"),
+				item->string, err.buf);
+			strbuf_reset(&err);
+			failures = 1;
+		}
+	}
+
+	ret = ref_transaction_commit(transaction, &err);
+	if (ret) {
+		if (refnames->nr == 1)
+			error(_("could not delete reference %s: %s"),
+			      refnames->items[0].string, err.buf);
+		else
+			error(_("could not delete references: %s"), err.buf);
+	}
+
+out:
+	if (!ret && failures)
+		ret = -1;
+	ref_transaction_free(transaction);
+	strbuf_release(&err);
 	free(msg);
-	return retval;
+	return ret;
 }
 
 int delete_refs(const char *msg, struct string_list *refnames,