Merge branch 'jt/fetch-v2-sideband'

"git fetch" and "git upload-pack" learned to send all exchange over the sideband channel while talking the v2 protocol. * jt/fetch-v2-sideband: tests: define GIT_TEST_SIDEBAND_ALL {fetch,upload}-pack: sideband v2 fetch response sideband: reverse its dependency on pkt-line pkt-line: introduce struct packet_writer pack-protocol.txt: accept error packets in any context Use packet_reader instead of packet_read_line
2025-12-12 20:36:24 +01:00 · 2019-02-05 14:26:11 -08:00
parent 33bea7358f 07c3c2aa16
commit 5f8b86db94
23 changed files with 522 additions and 303 deletions
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -70,6 +70,8 @@ static int allow_filter;
 static int allow_ref_in_want;
 static struct list_objects_filter_options filter_options;

+static int allow_sideband_all;
+
 static void reset_timeout(void)
 {
 	alarm(timeout);
@@ -356,7 +358,8 @@ static int ok_to_give_up(const struct object_array *have_obj,
 					    min_generation);
 }

-static int get_common_commits(struct object_array *have_obj,
+static int get_common_commits(struct packet_reader *reader,
+			      struct object_array *have_obj,
 			      struct object_array *want_obj)
 {
 	struct object_id oid;
@@ -368,12 +371,11 @@ static int get_common_commits(struct object_array *have_obj,
 	save_commit_buffer = 0;

 	for (;;) {
-		char *line = packet_read_line(0, NULL);
 		const char *arg;

 		reset_timeout();

-		if (!line) {
+		if (packet_reader_read(reader) != PACKET_READ_NORMAL) {
 			if (multi_ack == 2 && got_common
 			    && !got_other && ok_to_give_up(have_obj, want_obj)) {
 				sent_ready = 1;
@@ -392,7 +394,7 @@ static int get_common_commits(struct object_array *have_obj,
 			got_other = 0;
 			continue;
 		}
-		if (skip_prefix(line, "have ", &arg)) {
+		if (skip_prefix(reader->line, "have ", &arg)) {
 			switch (got_oid(arg, &oid, have_obj)) {
 			case -1: /* they have what we do not */
 				got_other = 1;
@@ -418,7 +420,7 @@ static int get_common_commits(struct object_array *have_obj,
 			}
 			continue;
 		}
-		if (!strcmp(line, "done")) {
+		if (!strcmp(reader->line, "done")) {
 			if (have_obj->nr > 0) {
 				if (multi_ack)
 					packet_write_fmt(1, "ACK %s\n", last_hex);
@@ -427,7 +429,7 @@ static int get_common_commits(struct object_array *have_obj,
 			packet_write_fmt(1, "NAK\n");
 			return -1;
 		}
-		die("git upload-pack: expected SHA1 list, got '%s'", line);
+		die("git upload-pack: expected SHA1 list, got '%s'", reader->line);
 	}
 }

@@ -615,13 +617,14 @@ error:
 	}
 }

-static void send_shallow(struct commit_list *result)
+static void send_shallow(struct packet_writer *writer,
+			 struct commit_list *result)
 {
 	while (result) {
 		struct object *object = &result->item->object;
 		if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
-			packet_write_fmt(1, "shallow %s",
-					 oid_to_hex(&object->oid));
+			packet_writer_write(writer, "shallow %s",
+					    oid_to_hex(&object->oid));
 			register_shallow(the_repository, &object->oid);
 			shallow_nr++;
 		}
@@ -629,7 +632,8 @@ static void send_shallow(struct commit_list *result)
 	}
 }

-static void send_unshallow(const struct object_array *shallows,
+static void send_unshallow(struct packet_writer *writer,
+			   const struct object_array *shallows,
 			   struct object_array *want_obj)
 {
 	int i;
@@ -638,8 +642,8 @@ static void send_unshallow(const struct object_array *shallows,
 		struct object *object = shallows->objects[i].item;
 		if (object->flags & NOT_SHALLOW) {
 			struct commit_list *parents;
-			packet_write_fmt(1, "unshallow %s",
-					 oid_to_hex(&object->oid));
+			packet_writer_write(writer, "unshallow %s",
+					    oid_to_hex(&object->oid));
 			object->flags &= ~CLIENT_SHALLOW;
 			/*
 			 * We want to _register_ "object" as shallow, but we
@@ -666,8 +670,7 @@ static void send_unshallow(const struct object_array *shallows,

 static int check_ref(const char *refname_full, const struct object_id *oid,
 		     int flag, void *cb_data);
-
-static void deepen(int depth, int deepen_relative,
+static void deepen(struct packet_writer *writer, int depth, int deepen_relative,
 		   struct object_array *shallows, struct object_array *want_obj)
 {
 	if (depth == INFINITE_DEPTH && !is_repository_shallow(the_repository)) {
@@ -692,7 +695,7 @@ static void deepen(int depth, int deepen_relative,
 		result = get_shallow_commits(&reachable_shallows,
 					     depth + 1,
 					     SHALLOW, NOT_SHALLOW);
-		send_shallow(result);
+		send_shallow(writer, result);
 		free_commit_list(result);
 		object_array_clear(&reachable_shallows);
 	} else {
@@ -700,14 +703,15 @@ static void deepen(int depth, int deepen_relative,

 		result = get_shallow_commits(want_obj, depth,
 					     SHALLOW, NOT_SHALLOW);
-		send_shallow(result);
+		send_shallow(writer, result);
 		free_commit_list(result);
 	}

-	send_unshallow(shallows, want_obj);
+	send_unshallow(writer, shallows, want_obj);
 }

-static void deepen_by_rev_list(int ac, const char **av,
+static void deepen_by_rev_list(struct packet_writer *writer, int ac,
+			       const char **av,
 			       struct object_array *shallows,
 			       struct object_array *want_obj)
 {
@@ -715,13 +719,14 @@ static void deepen_by_rev_list(int ac, const char **av,

 	close_commit_graph(the_repository);
 	result = get_shallow_commits_by_rev_list(ac, av, SHALLOW, NOT_SHALLOW);
-	send_shallow(result);
+	send_shallow(writer, result);
 	free_commit_list(result);
-	send_unshallow(shallows, want_obj);
+	send_unshallow(writer, shallows, want_obj);
 }

 /* Returns 1 if a shallow list is sent or 0 otherwise */
-static int send_shallow_list(int depth, int deepen_rev_list,
+static int send_shallow_list(struct packet_writer *writer,
+			     int depth, int deepen_rev_list,
 			     timestamp_t deepen_since,
 			     struct string_list *deepen_not,
 			     int deepen_relative,
@@ -733,7 +738,7 @@ static int send_shallow_list(int depth, int deepen_rev_list,
 	if (depth > 0 && deepen_rev_list)
 		die("git upload-pack: deepen and deepen-since (or deepen-not) cannot be used together");
 	if (depth > 0) {
-		deepen(depth, deepen_relative, shallows, want_obj);
+		deepen(writer, depth, deepen_relative, shallows, want_obj);
 		ret = 1;
 	} else if (deepen_rev_list) {
 		struct argv_array av = ARGV_ARRAY_INIT;
@@ -754,7 +759,7 @@ static int send_shallow_list(int depth, int deepen_rev_list,
 			struct object *o = want_obj->objects[i].item;
 			argv_array_push(&av, oid_to_hex(&o->oid));
 		}
-		deepen_by_rev_list(av.argc, av.argv, shallows, want_obj);
+		deepen_by_rev_list(writer, av.argc, av.argv, shallows, want_obj);
 		argv_array_clear(&av);
 		ret = 1;
 	} else {
@@ -839,7 +844,7 @@ static int process_deepen_not(const char *line, struct string_list *deepen_not,
 	return 0;
 }

-static void receive_needs(struct object_array *want_obj)
+static void receive_needs(struct packet_reader *reader, struct object_array *want_obj)
 {
 	struct object_array shallows = OBJECT_ARRAY_INIT;
 	struct string_list deepen_not = STRING_LIST_INIT_DUP;
@@ -848,39 +853,40 @@ static void receive_needs(struct object_array *want_obj)
 	timestamp_t deepen_since = 0;
 	int deepen_rev_list = 0;
 	int deepen_relative = 0;
+	struct packet_writer writer;

 	shallow_nr = 0;
+	packet_writer_init(&writer, 1);
 	for (;;) {
 		struct object *o;
 		const char *features;
 		struct object_id oid_buf;
-		char *line = packet_read_line(0, NULL);
 		const char *arg;

 		reset_timeout();
-		if (!line)
+		if (packet_reader_read(reader) != PACKET_READ_NORMAL)
 			break;

-		if (process_shallow(line, &shallows))
+		if (process_shallow(reader->line, &shallows))
 			continue;
-		if (process_deepen(line, &depth))
+		if (process_deepen(reader->line, &depth))
 			continue;
-		if (process_deepen_since(line, &deepen_since, &deepen_rev_list))
+		if (process_deepen_since(reader->line, &deepen_since, &deepen_rev_list))
 			continue;
-		if (process_deepen_not(line, &deepen_not, &deepen_rev_list))
+		if (process_deepen_not(reader->line, &deepen_not, &deepen_rev_list))
 			continue;

-		if (skip_prefix(line, "filter ", &arg)) {
+		if (skip_prefix(reader->line, "filter ", &arg)) {
 			if (!filter_capability_requested)
 				die("git upload-pack: filtering capability not negotiated");
 			parse_list_objects_filter(&filter_options, arg);
 			continue;
 		}

-		if (!skip_prefix(line, "want ", &arg) ||
+		if (!skip_prefix(reader->line, "want ", &arg) ||
 		    parse_oid_hex(arg, &oid_buf, &features))
 			die("git upload-pack: protocol error, "
-			    "expected to get object ID, not '%s'", line);
+			    "expected to get object ID, not '%s'", reader->line);

 		if (parse_feature_request(features, "deepen-relative"))
 			deepen_relative = 1;
@@ -907,9 +913,9 @@ static void receive_needs(struct object_array *want_obj)

 		o = parse_object(the_repository, &oid_buf);
 		if (!o) {
-			packet_write_fmt(1,
-					 "ERR upload-pack: not our ref %s",
-					 oid_to_hex(&oid_buf));
+			packet_writer_error(&writer,
+					    "upload-pack: not our ref %s",
+					    oid_to_hex(&oid_buf));
 			die("git upload-pack: not our ref %s",
 			    oid_to_hex(&oid_buf));
 		}
@@ -938,7 +944,7 @@ static void receive_needs(struct object_array *want_obj)
 	if (depth == 0 && !deepen_rev_list && shallows.nr == 0)
 		return;

-	if (send_shallow_list(depth, deepen_rev_list, deepen_since,
+	if (send_shallow_list(&writer, depth, deepen_rev_list, deepen_since,
 			      &deepen_not, deepen_relative, &shallows,
 			      want_obj))
 		packet_flush(1);
@@ -1056,6 +1062,8 @@ static int upload_pack_config(const char *var, const char *value, void *unused)
 		allow_filter = git_config_bool(var, value);
 	} else if (!strcmp("uploadpack.allowrefinwant", var)) {
 		allow_ref_in_want = git_config_bool(var, value);
+	} else if (!strcmp("uploadpack.allowsidebandall", var)) {
+		allow_sideband_all = git_config_bool(var, value);
 	}

 	if (current_config_scope() != CONFIG_SCOPE_REPO) {
@@ -1070,6 +1078,7 @@ void upload_pack(struct upload_pack_options *options)
 {
 	struct string_list symref = STRING_LIST_INIT_DUP;
 	struct object_array want_obj = OBJECT_ARRAY_INIT;
+	struct packet_reader reader;

 	stateless_rpc = options->stateless_rpc;
 	timeout = options->timeout;
@@ -1093,10 +1102,14 @@ void upload_pack(struct upload_pack_options *options)
 	if (options->advertise_refs)
 		return;

-	receive_needs(&want_obj);
+	packet_reader_init(&reader, 0, NULL, 0,
+			   PACKET_READ_CHOMP_NEWLINE |
+			   PACKET_READ_DIE_ON_ERR_PACKET);
+
+	receive_needs(&reader, &want_obj);
 	if (want_obj.nr) {
 		struct object_array have_obj = OBJECT_ARRAY_INIT;
-		get_common_commits(&have_obj, &want_obj);
+		get_common_commits(&reader, &have_obj, &want_obj);
 		create_pack_file(&have_obj, &want_obj);
 	}
 }
@@ -1113,6 +1126,8 @@ struct upload_pack_data {
 	int deepen_rev_list;
 	int deepen_relative;

+	struct packet_writer writer;
+
 	unsigned stateless_rpc : 1;

 	unsigned use_thin_pack : 1;
@@ -1136,6 +1151,7 @@ static void upload_pack_data_init(struct upload_pack_data *data)
 	data->haves = haves;
 	data->shallows = shallows;
 	data->deepen_not = deepen_not;
+	packet_writer_init(&data->writer, 1);
 }

 static void upload_pack_data_clear(struct upload_pack_data *data)
@@ -1147,7 +1163,8 @@ static void upload_pack_data_clear(struct upload_pack_data *data)
 	string_list_clear(&data->deepen_not, 0);
 }

-static int parse_want(const char *line, struct object_array *want_obj)
+static int parse_want(struct packet_writer *writer, const char *line,
+		      struct object_array *want_obj)
 {
 	const char *arg;
 	if (skip_prefix(line, "want ", &arg)) {
@@ -1160,9 +1177,9 @@ static int parse_want(const char *line, struct object_array *want_obj)

 		o = parse_object(the_repository, &oid);
 		if (!o) {
-			packet_write_fmt(1,
-					 "ERR upload-pack: not our ref %s",
-					 oid_to_hex(&oid));
+			packet_writer_error(writer,
+					    "upload-pack: not our ref %s",
+					    oid_to_hex(&oid));
 			die("git upload-pack: not our ref %s",
 			    oid_to_hex(&oid));
 		}
@@ -1178,7 +1195,8 @@ static int parse_want(const char *line, struct object_array *want_obj)
 	return 0;
 }

-static int parse_want_ref(const char *line, struct string_list *wanted_refs,
+static int parse_want_ref(struct packet_writer *writer, const char *line,
+			  struct string_list *wanted_refs,
 			  struct object_array *want_obj)
 {
 	const char *arg;
@@ -1188,7 +1206,7 @@ static int parse_want_ref(const char *line, struct string_list *wanted_refs,
 		struct object *o;

 		if (read_ref(arg, &oid)) {
-			packet_write_fmt(1, "ERR unknown ref %s", arg);
+			packet_writer_error(writer, "unknown ref %s", arg);
 			die("unknown ref %s", arg);
 		}

@@ -1231,10 +1249,11 @@ static void process_args(struct packet_reader *request,
 		const char *p;

 		/* process want */
-		if (parse_want(arg, want_obj))
+		if (parse_want(&data->writer, arg, want_obj))
 			continue;
 		if (allow_ref_in_want &&
-		    parse_want_ref(arg, &data->wanted_refs, want_obj))
+		    parse_want_ref(&data->writer, arg, &data->wanted_refs,
+				   want_obj))
 			continue;
 		/* process have line */
 		if (parse_have(arg, &data->haves))
@@ -1283,6 +1302,13 @@ static void process_args(struct packet_reader *request,
 			continue;
 		}

+		if ((git_env_bool("GIT_TEST_SIDEBAND_ALL", 0) ||
+		     allow_sideband_all) &&
+		    !strcmp(arg, "sideband-all")) {
+			data->writer.use_sideband = 1;
+			continue;
+		}
+
 		/* ignore unknown lines maybe? */
 		die("unexpected line: '%s'", arg);
 	}
@@ -1328,26 +1354,26 @@ static int process_haves(struct oid_array *haves, struct oid_array *common,
 	return 0;
 }

-static int send_acks(struct oid_array *acks, struct strbuf *response,
+static int send_acks(struct packet_writer *writer, struct oid_array *acks,
 		     const struct object_array *have_obj,
 		     struct object_array *want_obj)
 {
 	int i;

-	packet_buf_write(response, "acknowledgments\n");
+	packet_writer_write(writer, "acknowledgments\n");

 	/* Send Acks */
 	if (!acks->nr)
-		packet_buf_write(response, "NAK\n");
+		packet_writer_write(writer, "NAK\n");

 	for (i = 0; i < acks->nr; i++) {
-		packet_buf_write(response, "ACK %s\n",
-				 oid_to_hex(&acks->oid[i]));
+		packet_writer_write(writer, "ACK %s\n",
+				    oid_to_hex(&acks->oid[i]));
 	}

 	if (ok_to_give_up(have_obj, want_obj)) {
 		/* Send Ready */
-		packet_buf_write(response, "ready\n");
+		packet_writer_write(writer, "ready\n");
 		return 1;
 	}

@@ -1359,25 +1385,20 @@ static int process_haves_and_send_acks(struct upload_pack_data *data,
 				       struct object_array *want_obj)
 {
 	struct oid_array common = OID_ARRAY_INIT;
-	struct strbuf response = STRBUF_INIT;
 	int ret = 0;

 	process_haves(&data->haves, &common, have_obj);
 	if (data->done) {
 		ret = 1;
-	} else if (send_acks(&common, &response, have_obj, want_obj)) {
-		packet_buf_delim(&response);
+	} else if (send_acks(&data->writer, &common, have_obj, want_obj)) {
+		packet_writer_delim(&data->writer);
 		ret = 1;
 	} else {
 		/* Add Flush */
-		packet_buf_flush(&response);
+		packet_writer_flush(&data->writer);
 		ret = 0;
 	}

-	/* Send response */
-	write_or_die(1, response.buf, response.len);
-	strbuf_release(&response);
-
 	oid_array_clear(&data->haves);
 	oid_array_clear(&common);
 	return ret;
@@ -1390,15 +1411,15 @@ static void send_wanted_ref_info(struct upload_pack_data *data)
 	if (!data->wanted_refs.nr)
 		return;

-	packet_write_fmt(1, "wanted-refs\n");
+	packet_writer_write(&data->writer, "wanted-refs\n");

 	for_each_string_list_item(item, &data->wanted_refs) {
-		packet_write_fmt(1, "%s %s\n",
-				 oid_to_hex(item->util),
-				 item->string);
+		packet_writer_write(&data->writer, "%s %s\n",
+				    oid_to_hex(item->util),
+				    item->string);
 	}

-	packet_delim(1);
+	packet_writer_delim(&data->writer);
 }

 static void send_shallow_info(struct upload_pack_data *data,
@@ -1409,15 +1430,16 @@ static void send_shallow_info(struct upload_pack_data *data,
 	    !is_repository_shallow(the_repository))
 		return;

-	packet_write_fmt(1, "shallow-info\n");
+	packet_writer_write(&data->writer, "shallow-info\n");

-	if (!send_shallow_list(data->depth, data->deepen_rev_list,
+	if (!send_shallow_list(&data->writer, data->depth,
+			       data->deepen_rev_list,
 			       data->deepen_since, &data->deepen_not,
 			       data->deepen_relative,
 			       &data->shallows, want_obj) &&
 	    is_repository_shallow(the_repository))
-		deepen(INFINITE_DEPTH, data->deepen_relative, &data->shallows,
-		       want_obj);
+		deepen(&data->writer, INFINITE_DEPTH, data->deepen_relative,
+		       &data->shallows, want_obj);

 	packet_delim(1);
 }
@@ -1479,7 +1501,7 @@ int upload_pack_v2(struct repository *r, struct argv_array *keys,
 			send_wanted_ref_info(&data);
 			send_shallow_info(&data, &want_obj);

-			packet_write_fmt(1, "packfile\n");
+			packet_writer_write(&data.writer, "packfile\n");
 			create_pack_file(&have_obj, &want_obj);
 			state = FETCH_DONE;
 			break;
@@ -1500,6 +1522,7 @@ int upload_pack_advertise(struct repository *r,
 	if (value) {
 		int allow_filter_value;
 		int allow_ref_in_want;
+		int allow_sideband_all_value;

 		strbuf_addstr(value, "shallow");

@@ -1514,6 +1537,13 @@ int upload_pack_advertise(struct repository *r,
 					 &allow_ref_in_want) &&
 		    allow_ref_in_want)
 			strbuf_addstr(value, " ref-in-want");
+
+		if (git_env_bool("GIT_TEST_SIDEBAND_ALL", 0) ||
+		    (!repo_config_get_bool(the_repository,
+					   "uploadpack.allowsidebandall",
+					   &allow_sideband_all_value) &&
+		     allow_sideband_all_value))
+			strbuf_addstr(value, " sideband-all");
 	}

 	return 1;