fetch-object-info: parse type from server response

The server can handle type requests but does not advertise the
capability yet. Prepare the client to know how to parse the server
response once the server advertises the type capability.

Mentored-by: Karthik Nayak <karthik.188@gmail.com>
Mentored-by: Chandra Pratap <chandrapratap3519@gmail.com>
Signed-off-by: Pablo Sabater <pabloosabaterr@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/cat-file.c

@@ -844,6 +844,8 @@ static void parse_cmd_remote_object_info(struct batch_options *opt,
 
 	if (data->info.sizep)
 		results.wants_size = 1;
+	if (data->info.typep)
+		results.wants_type = 1;
 
 	if (get_remote_info(count, argv, &results, &object_info_oids))
 		die(_("failed to get object info from the remote: %s"), argv[0]);
@@ -852,6 +854,8 @@ static void parse_cmd_remote_object_info(struct batch_options *opt,
 	string_list_append(&data->remote_allowed_atoms, "objectname");
 	if (results.sizes)
 		string_list_append(&data->remote_allowed_atoms, "objectsize");
+	if (results.types)
+		string_list_append(&data->remote_allowed_atoms, "objecttype");
 
 	data->skip_object_info = 1;
 	for (size_t i = 0; i < results.nr; i++) {
@@ -870,6 +874,9 @@ static void parse_cmd_remote_object_info(struct batch_options *opt,
 		if (results.sizes)
 			data->size = results.sizes[i];
 
+		if (results.types)
+			data->type = results.types[i];
+
 		opt->batch_mode = BATCH_MODE_INFO;
 		data->is_remote = 1;
 		batch_object_write(argv[i + 1], output, opt, data, NULL, 0);

fetch-object-info.c

@@ -1,6 +1,7 @@
 #include "git-compat-util.h"
 #include "gettext.h"
 #include "hex.h"
+#include "object.h"
 #include "pkt-line.h"
 #include "connect.h"
 #include "oid-array.h"
@@ -12,7 +13,8 @@
 static void send_object_info_request(const int fd_out,
 				     const struct string_list *server_options,
 				     struct oid_array *oids,
-				     unsigned ask_size)
+				     unsigned ask_size,
+				     unsigned ask_type)
 {
 	struct strbuf req_buf = STRBUF_INIT;
 
@@ -21,6 +23,9 @@ static void send_object_info_request(const int fd_out,
 	if (ask_size)
 		packet_buf_write(&req_buf, "size");
 
+	if (ask_type)
+		packet_buf_write(&req_buf, "type");
+
 	if (oids)
 		for (size_t i = 0; i < oids->nr; i++)
 			packet_buf_write(&req_buf, "oid %s",
@@ -56,7 +61,9 @@ void fetch_object_info(enum protocol_version version,
 		       int fd_out)
 {
 	unsigned ask_size = 0;
+	unsigned ask_type = 0;
 	int size_index = -1;
+	int type_index = -1;
 	size_t wanted;
 
 	results->nr = oids->nr;
@@ -71,11 +78,16 @@ void fetch_object_info(enum protocol_version version,
 		    server_supports_feature("object-info", "size", 0))
 			ask_size = 1;
 
+		if (results->wants_type &&
+		    server_supports_feature("object-info", "type", 0))
+			ask_type = 1;
+
 		/*
 		 * Even if no options are left, we still send the oid so we get
 		 * at least an existence check.
 		 */
-		send_object_info_request(fd_out, server_options, oids, ask_size);
+		send_object_info_request(fd_out, server_options, oids, ask_size,
+					 ask_type);
 		break;
 	case protocol_v1:
 	case protocol_v0:
@@ -83,7 +95,7 @@ void fetch_object_info(enum protocol_version version,
 	case protocol_unknown_version:
 		BUG("unknown protocol version");
 	}
-	wanted = ask_size;
+	wanted = ask_size + ask_type;
 
 	for (size_t i = 0; i < wanted; i++) {
 		if (packet_reader_read(reader) != PACKET_READ_NORMAL) {
@@ -100,6 +112,13 @@ void fetch_object_info(enum protocol_version version,
 				die(_("object-info: duplicate 'size' attribute"));
 			size_index = (int)i;
 			CALLOC_ARRAY(results->sizes, results->nr);
+		} else if (!strcmp(reader->line, "type")) {
+			if (!ask_type)
+				die(_("object-info: unrequested 'type' attribute"));
+			if (results->types)
+				die(_("object-info: duplicate 'type' attribute"));
+			type_index = (int)i;
+			CALLOC_ARRAY(results->types, results->nr);
 		} else {
 			die(_("object-info: unknown attribute '%s'"),
 			    reader->line);
@@ -149,6 +168,18 @@ void fetch_object_info(enum protocol_version version,
 			    object_info_values.items[0].string,
 			    object_info_values.items[size_index + 1].string);
 
+		if (results->types) {
+			const char *type_str =
+				object_info_values.items[type_index + 1].string;
+			int type = type_from_string_gently(type_str, -1, 1);
+
+			if (type < 0)
+				die(_("object-info: object %s has invalid type '%s'"),
+				    object_info_values.items[0].string, type_str);
+
+			results->types[i] = type;
+		}
+
 		string_list_clear(&object_info_values, 0);
 	}
 
@@ -162,6 +193,7 @@ void fetch_object_info(enum protocol_version version,
 void free_fetch_object_info_results(struct fetch_object_info_results *results)
 {
 	free(results->sizes);
+	free(results->types);
 	free(results->unrecognized);
 	memset(results, 0, sizeof(*results));
 }

fetch-object-info.h

@@ -1,14 +1,17 @@
 #ifndef FETCH_OBJECT_INFO_H
 #define FETCH_OBJECT_INFO_H
 
+#include "object.h"
 #include "pkt-line.h"
 #include "protocol.h"
 
 struct fetch_object_info_results {
 	size_t *sizes;
+	enum object_type *types;
 	uint8_t *unrecognized;
 	size_t nr;
 	unsigned wants_size:1;
+	unsigned wants_type:1;
 };
 
 #define FETCH_OBJECT_INFO_RESULTS_INIT { 0 }