Merge branch 'ps/receive-use-only-advertised'

"git receive-pack" used to use all the local refs as the boundary for
checking connectivity of the data "git push" sent, but now it uses
only the refs that it advertised to the pusher. In a repository with
the .hideRefs configuration, this reduces the resources needed to
perform the check.
cf. <221028.86bkpw805n.gmgdl@evledraar.gmail.com>
cf. <xmqqr0yrizqm.fsf@gitster.g>

* ps/receive-use-only-advertised:
  receive-pack: only use visible refs for connectivity check
  rev-parse: add `--exclude-hidden=` option
  revision: add new parameter to exclude hidden refs
  revision: introduce struct to handle exclusions
  revision: move together exclusion-related functions
  refs: get rid of global list of hidden refs
  refs: fix memory leak when parsing hideRefs config

Documentation/git-rev-parse.txt

@@ -197,6 +197,13 @@ respectively, and they must begin with `refs/` when applied to `--glob`
 or `--all`. If a trailing '/{asterisk}' is intended, it must be given
 explicitly.
 
+--exclude-hidden=[receive|uploadpack]::
+	Do not include refs that would be hidden by `git-receive-pack` or
+	`git-upload-pack` by consulting the appropriate `receive.hideRefs` or
+	`uploadpack.hideRefs` configuration along with `transfer.hideRefs` (see
+	linkgit:git-config[1]). This option affects the next pseudo-ref option
+	`--all` or `--glob` and is cleared after processing them.
+
 --disambiguate=<prefix>::
 	Show every object whose name begins with the given prefix.
 	The <prefix> must be at least 4 hexadecimal digits long to

Documentation/rev-list-options.txt

@@ -195,6 +195,13 @@ respectively, and they must begin with `refs/` when applied to `--glob`
 or `--all`. If a trailing '/{asterisk}' is intended, it must be given
 explicitly.
 
+--exclude-hidden=[receive|uploadpack]::
+	Do not include refs that would be hidden by `git-receive-pack` or
+	`git-upload-pack` by consulting the appropriate `receive.hideRefs` or
+	`uploadpack.hideRefs` configuration along with `transfer.hideRefs` (see
+	linkgit:git-config[1]). This option affects the next pseudo-ref option
+	`--all` or `--glob` and is cleared after processing them.
+
 --reflog::
 	Pretend as if all objects mentioned by reflogs are listed on the
 	command line as `<commit>`.

builtin/receive-pack.c

@@ -80,6 +80,7 @@ static struct object_id push_cert_oid;
 static struct signature_check sigcheck;
 static const char *push_cert_nonce;
 static const char *cert_nonce_seed;
+static struct string_list hidden_refs = STRING_LIST_INIT_DUP;
 
 static const char *NONCE_UNSOLICITED = "UNSOLICITED";
 static const char *NONCE_BAD = "BAD";
@@ -130,7 +131,7 @@ static enum deny_action parse_deny_action(const char *var, const char *value)
 
 static int receive_pack_config(const char *var, const char *value, void *cb)
 {
-	int status = parse_hide_refs_config(var, value, "receive");
+	int status = parse_hide_refs_config(var, value, "receive", &hidden_refs);
 
 	if (status)
 		return status;
@@ -296,7 +297,7 @@ static int show_ref_cb(const char *path_full, const struct object_id *oid,
 	struct oidset *seen = data;
 	const char *path = strip_namespace(path_full);
 
-	if (ref_is_hidden(path, path_full))
+	if (ref_is_hidden(path, path_full, &hidden_refs))
 		return 0;
 
 	/*
@@ -1794,7 +1795,7 @@ static void reject_updates_to_hidden(struct command *commands)
 		strbuf_setlen(&refname_full, prefix_len);
 		strbuf_addstr(&refname_full, cmd->ref_name);
 
-		if (!ref_is_hidden(cmd->ref_name, refname_full.buf))
+		if (!ref_is_hidden(cmd->ref_name, refname_full.buf, &hidden_refs))
 			continue;
 		if (is_null_oid(&cmd->new_oid))
 			cmd->error_string = "deny deleting a hidden ref";
@@ -1928,6 +1929,8 @@ static void execute_commands(struct command *commands,
 	opt.err_fd = err_fd;
 	opt.progress = err_fd && !quiet;
 	opt.env = tmp_objdir_env(tmp_objdir);
+	opt.exclude_hidden_refs_section = "receive";
+
 	if (check_connected(iterate_receive_command_list, &data, &opt))
 		set_connectivity_errors(commands, si);
 
@@ -2591,6 +2594,7 @@ int cmd_receive_pack(int argc, const char **argv, const char *prefix)
 		packet_flush(1);
 	oid_array_clear(&shallow);
 	oid_array_clear(&ref);
+	string_list_clear(&hidden_refs, 0);
 	free((void *)push_cert_nonce);
 	return 0;
 }

builtin/rev-list.c

@@ -38,6 +38,7 @@ static const char rev_list_usage[] =
 "    --tags\n"
 "    --remotes\n"
 "    --stdin\n"
+"    --exclude-hidden=[receive|uploadpack]\n"
 "    --quiet\n"
 "  ordering output:\n"
 "    --topo-order\n"

builtin/rev-parse.c

@@ -39,7 +39,7 @@ static int abbrev_ref_strict;
 static int output_sq;
 
 static int stuck_long;
-static struct string_list *ref_excludes;
+static struct ref_exclusions ref_excludes = REF_EXCLUSIONS_INIT;
 
 /*
  * Some arguments are relevant "revision" arguments,
@@ -198,7 +198,7 @@ static int show_default(void)
 static int show_reference(const char *refname, const struct object_id *oid,
 			  int flag UNUSED, void *cb_data UNUSED)
 {
-	if (ref_excluded(ref_excludes, refname))
+	if (ref_excluded(&ref_excludes, refname))
 		return 0;
 	show_rev(NORMAL, oid, refname);
 	return 0;
@@ -585,7 +585,7 @@ static void handle_ref_opt(const char *pattern, const char *prefix)
 		for_each_glob_ref_in(show_reference, pattern, prefix, NULL);
 	else
 		for_each_ref_in(prefix, show_reference, NULL);
-	clear_ref_exclusion(&ref_excludes);
+	clear_ref_exclusions(&ref_excludes);
 }
 
 enum format_type {
@@ -863,7 +863,7 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 			}
 			if (!strcmp(arg, "--all")) {
 				for_each_ref(show_reference, NULL);
-				clear_ref_exclusion(&ref_excludes);
+				clear_ref_exclusions(&ref_excludes);
 				continue;
 			}
 			if (skip_prefix(arg, "--disambiguate=", &arg)) {
@@ -876,10 +876,14 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 				continue;
 			}
 			if (opt_with_value(arg, "--branches", &arg)) {
+				if (ref_excludes.hidden_refs_configured)
+					return error(_("--exclude-hidden cannot be used together with --branches"));
 				handle_ref_opt(arg, "refs/heads/");
 				continue;
 			}
 			if (opt_with_value(arg, "--tags", &arg)) {
+				if (ref_excludes.hidden_refs_configured)
+					return error(_("--exclude-hidden cannot be used together with --tags"));
 				handle_ref_opt(arg, "refs/tags/");
 				continue;
 			}
@@ -888,13 +892,19 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 				continue;
 			}
 			if (opt_with_value(arg, "--remotes", &arg)) {
+				if (ref_excludes.hidden_refs_configured)
+					return error(_("--exclude-hidden cannot be used together with --remotes"));
 				handle_ref_opt(arg, "refs/remotes/");
 				continue;
 			}
 			if (skip_prefix(arg, "--exclude=", &arg)) {
 				add_ref_exclusion(&ref_excludes, arg);
 				continue;
 			}
+			if (skip_prefix(arg, "--exclude-hidden=", &arg)) {
+				exclude_hidden_refs(&ref_excludes, arg);
+				continue;
+			}
 			if (!strcmp(arg, "--show-toplevel")) {
 				const char *work_tree = get_git_work_tree();
 				if (work_tree)

connected.c

@@ -100,6 +100,9 @@ int check_connected(oid_iterate_fn fn, void *cb_data,
 		strvec_push(&rev_list.args, "--exclude-promisor-objects");
 	if (!opt->is_deepening_fetch) {
 		strvec_push(&rev_list.args, "--not");
+		if (opt->exclude_hidden_refs_section)
+			strvec_pushf(&rev_list.args, "--exclude-hidden=%s",
+				     opt->exclude_hidden_refs_section);
 		strvec_push(&rev_list.args, "--all");
 	}
 	strvec_push(&rev_list.args, "--quiet");

connected.h

@@ -46,6 +46,13 @@ struct check_connected_options {
 	 * during a fetch.
 	 */
 	unsigned is_deepening_fetch : 1;
+
+	/*
+	 * If not NULL, use `--exclude-hidden=$section` to exclude all refs
+	 * hidden via the `$section.hideRefs` config from the set of
+	 * already-reachable refs.
+	 */
+	const char *exclude_hidden_refs_section;
 };
 
 #define CHECK_CONNECTED_INIT { 0 }

ls-refs.c

@@ -6,6 +6,7 @@
 #include "ls-refs.h"
 #include "pkt-line.h"
 #include "config.h"
+#include "string-list.h"
 
 static int config_read;
 static int advertise_unborn;
@@ -73,6 +74,7 @@ struct ls_refs_data {
 	unsigned symrefs;
 	struct strvec prefixes;
 	struct strbuf buf;
+	struct string_list hidden_refs;
 	unsigned unborn : 1;
 };
 
@@ -84,7 +86,7 @@ static int send_ref(const char *refname, const struct object_id *oid,
 
 	strbuf_reset(&data->buf);
 
-	if (ref_is_hidden(refname_nons, refname))
+	if (ref_is_hidden(refname_nons, refname, &data->hidden_refs))
 		return 0;
 
 	if (!ref_match(&data->prefixes, refname_nons))
@@ -137,14 +139,15 @@ static void send_possibly_unborn_head(struct ls_refs_data *data)
 }
 
 static int ls_refs_config(const char *var, const char *value,
-			  void *data UNUSED)
+			  void *cb_data)
 {
+	struct ls_refs_data *data = cb_data;
 	/*
 	 * We only serve fetches over v2 for now, so respect only "uploadpack"
 	 * config. This may need to eventually be expanded to "receive", but we
 	 * don't yet know how that information will be passed to ls-refs.
 	 */
-	return parse_hide_refs_config(var, value, "uploadpack");
+	return parse_hide_refs_config(var, value, "uploadpack", &data->hidden_refs);
 }
 
 int ls_refs(struct repository *r, struct packet_reader *request)
@@ -154,9 +157,10 @@ int ls_refs(struct repository *r, struct packet_reader *request)
 	memset(&data, 0, sizeof(data));
 	strvec_init(&data.prefixes);
 	strbuf_init(&data.buf, 0);
+	string_list_init_dup(&data.hidden_refs);
 
 	ensure_config_read();
-	git_config(ls_refs_config, NULL);
+	git_config(ls_refs_config, &data);
 
 	while (packet_reader_read(request) == PACKET_READ_NORMAL) {
 		const char *arg = request->line;
@@ -195,6 +199,7 @@ int ls_refs(struct repository *r, struct packet_reader *request)
 	packet_fflush(stdout);
 	strvec_clear(&data.prefixes);
 	strbuf_release(&data.buf);
+	string_list_clear(&data.hidden_refs, 0);
 	return 0;
 }
 

refs.c

@@ -1414,9 +1414,8 @@ char *shorten_unambiguous_ref(const char *refname, int strict)
 					    refname, strict);
 }
 
-static struct string_list *hide_refs;
-
-int parse_hide_refs_config(const char *var, const char *value, const char *section)
+int parse_hide_refs_config(const char *var, const char *value, const char *section,
+			   struct string_list *hide_refs)
 {
 	const char *key;
 	if (!strcmp("transfer.hiderefs", var) ||
@@ -1431,21 +1430,16 @@ int parse_hide_refs_config(const char *var, const char *value, const char *secti
 		len = strlen(ref);
 		while (len && ref[len - 1] == '/')
 			ref[--len] = '\0';
-		if (!hide_refs) {
-			CALLOC_ARRAY(hide_refs, 1);
-			hide_refs->strdup_strings = 1;
-		}
-		string_list_append(hide_refs, ref);
+		string_list_append_nodup(hide_refs, ref);
 	}
 	return 0;
 }
 
-int ref_is_hidden(const char *refname, const char *refname_full)
+int ref_is_hidden(const char *refname, const char *refname_full,
+		  const struct string_list *hide_refs)
 {
 	int i;
 
-	if (!hide_refs)
-		return 0;
 	for (i = hide_refs->nr - 1; i >= 0; i--) {
 		const char *match = hide_refs->items[i].string;
 		const char *subject;

refs.h

@@ -808,7 +808,8 @@ int update_ref(const char *msg, const char *refname,
 	       const struct object_id *new_oid, const struct object_id *old_oid,
 	       unsigned int flags, enum action_on_err onerr);
 
-int parse_hide_refs_config(const char *var, const char *value, const char *);
+int parse_hide_refs_config(const char *var, const char *value, const char *,
+			   struct string_list *);
 
 /*
  * Check whether a ref is hidden. If no namespace is set, both the first and
@@ -818,7 +819,7 @@ int parse_hide_refs_config(const char *var, const char *value, const char *);
  * the ref is outside that namespace, the first parameter is NULL. The second
  * parameter always points to the full ref name.
  */
-int ref_is_hidden(const char *, const char *);
+int ref_is_hidden(const char *, const char *, const struct string_list *);
 
 /* Is this a per-worktree ref living in the refs/ namespace? */
 int is_per_worktree_ref(const char *refname);