fetch: define shallow boundary with --shallow-since

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/fetch-options.txt

@@ -14,6 +14,10 @@
 	linkgit:git-clone[1]), deepen or shorten the history to the specified
 	number of commits. Tags for the deepened commits are not fetched.
 
+--shallow-since=<date>::
+	Deepen or shorten the history of a shallow repository to
+	include all reachable commits after <date>.
+
 --unshallow::
 	If the source repository is complete, convert a shallow
 	repository to a complete one, removing all the limitations

Documentation/git-fetch-pack.txt

@@ -87,6 +87,10 @@ be in a separate packet, and the list must end with a flush packet.
 	'git-upload-pack' treats the special depth 2147483647 as
 	infinite even if there is an ancestor-chain that long.
 
+--shallow-since=<date>::
+	Deepen or shorten the history of a shallow'repository to
+	include all reachable commits after <date>.
+
 --no-progress::
 	Do not show the progress.
 

Documentation/gitremote-helpers.txt

@@ -415,6 +415,9 @@ set by Git if the remote helper has the 'option' capability.
 'option depth' <depth>::
 	Deepens the history of a shallow repository.
 
+'option deepen-since <timestamp>::
+	Deepens the history of a shallow repository based on time.
+
 'option followtags' {'true'|'false'}::
 	If enabled the helper should automatically fetch annotated
 	tag objects if the object the tag points at was transferred

builtin/fetch-pack.c

@@ -104,6 +104,10 @@ int cmd_fetch_pack(int argc, const char **argv, const char *prefix)
 			args.depth = strtol(arg, NULL, 0);
 			continue;
 		}
+		if (skip_prefix(arg, "--shallow-since=", &arg)) {
+			args.deepen_since = xstrdup(arg);
+			continue;
+		}
 		if (!strcmp("--no-progress", arg)) {
 			args.no_progress = 1;
 			continue;

builtin/fetch.c

@@ -36,9 +36,10 @@ static int prune = -1; /* unspecified */
 
 static int all, append, dry_run, force, keep, multiple, update_head_ok, verbosity;
 static int progress = -1, recurse_submodules = RECURSE_SUBMODULES_DEFAULT;
-static int tags = TAGS_DEFAULT, unshallow, update_shallow;
+static int tags = TAGS_DEFAULT, unshallow, update_shallow, deepen;
 static int max_children = 1;
 static const char *depth;
+static const char *deepen_since;
 static const char *upload_pack;
 static struct strbuf default_rla = STRBUF_INIT;
 static struct transport *gtransport;
@@ -115,6 +116,8 @@ static struct option builtin_fetch_options[] = {
 	OPT_BOOL(0, "progress", &progress, N_("force progress reporting")),
 	OPT_STRING(0, "depth", &depth, N_("depth"),
 		   N_("deepen history of shallow clone")),
+	OPT_STRING(0, "shallow-since", &deepen_since, N_("time"),
+		   N_("deepen history of shallow repository based on time")),
 	{ OPTION_SET_INT, 0, "unshallow", &unshallow, NULL,
 		   N_("convert to a complete repository"),
 		   PARSE_OPT_NONEG | PARSE_OPT_NOARG, NULL, 1 },
@@ -754,7 +757,7 @@ static int quickfetch(struct ref *ref_map)
 	 * really need to perform.  Claiming failure now will ensure
 	 * we perform the network exchange to deepen our history.
 	 */
-	if (depth)
+	if (deepen)
 		return -1;
 	return check_everything_connected(iterate_ref_map, 1, &rm);
 }
@@ -859,7 +862,7 @@ static void set_option(struct transport *transport, const char *name, const char
 			name, transport->url);
 }
 
-static struct transport *prepare_transport(struct remote *remote)
+static struct transport *prepare_transport(struct remote *remote, int deepen)
 {
 	struct transport *transport;
 	transport = transport_get(remote, NULL);
@@ -870,6 +873,8 @@ static struct transport *prepare_transport(struct remote *remote)
 		set_option(transport, TRANS_OPT_KEEP, "yes");
 	if (depth)
 		set_option(transport, TRANS_OPT_DEPTH, depth);
+	if (deepen && deepen_since)
+		set_option(transport, TRANS_OPT_DEEPEN_SINCE, deepen_since);
 	if (update_shallow)
 		set_option(transport, TRANS_OPT_UPDATE_SHALLOW, "yes");
 	return transport;
@@ -877,8 +882,18 @@ static struct transport *prepare_transport(struct remote *remote)
 
 static void backfill_tags(struct transport *transport, struct ref *ref_map)
 {
-	if (transport->cannot_reuse) {
-		gsecondary = prepare_transport(transport->remote);
+	int cannot_reuse;
+
+	/*
+	 * Once we have set TRANS_OPT_DEEPEN_SINCE, we can't unset it
+	 * when remote helper is used (setting it to an empty string
+	 * is not unsetting). We could extend the remote helper
+	 * protocol for that, but for now, just force a new connection
+	 * without deepen-since.
+	 */
+	cannot_reuse = transport->cannot_reuse || deepen_since;
+	if (cannot_reuse) {
+		gsecondary = prepare_transport(transport->remote, 0);
 		transport = gsecondary;
 	}
 
@@ -1095,7 +1110,7 @@ static int fetch_one(struct remote *remote, int argc, const char **argv)
 		die(_("No remote repository specified.  Please, specify either a URL or a\n"
 		    "remote name from which new revisions should be fetched."));
 
-	gtransport = prepare_transport(remote);
+	gtransport = prepare_transport(remote, 1);
 
 	if (prune < 0) {
 		/* no command line request */
@@ -1167,6 +1182,8 @@ int cmd_fetch(int argc, const char **argv, const char *prefix)
 	/* no need to be strict, transport_set_option() will validate it again */
 	if (depth && atoi(depth) < 1)
 		die(_("depth %s is not a positive number"), depth);
+	if (depth || deepen_since)
+		deepen = 1;
 
 	if (recurse_submodules != RECURSE_SUBMODULES_OFF) {
 		if (recurse_submodules_default) {

fetch-pack.c

@@ -21,6 +21,7 @@ static int fetch_unpack_limit = -1;
 static int unpack_limit = 100;
 static int prefer_ofs_delta = 1;
 static int no_done;
+static int deepen_since_ok;
 static int fetch_fsck_objects = -1;
 static int transfer_fsck_objects = -1;
 static int agent_supported;
@@ -326,6 +327,7 @@ static int find_common(struct fetch_pack_args *args,
 			if (args->no_progress)   strbuf_addstr(&c, " no-progress");
 			if (args->include_tag)   strbuf_addstr(&c, " include-tag");
 			if (prefer_ofs_delta)   strbuf_addstr(&c, " ofs-delta");
+			if (deepen_since_ok)    strbuf_addstr(&c, " deepen-since");
 			if (agent_supported)    strbuf_addf(&c, " agent=%s",
 							    git_user_agent_sanitized());
 			packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf);
@@ -345,6 +347,10 @@ static int find_common(struct fetch_pack_args *args,
 		write_shallow_commits(&req_buf, 1, NULL);
 	if (args->depth > 0)
 		packet_buf_write(&req_buf, "deepen %d", args->depth);
+	if (args->deepen_since) {
+		unsigned long max_age = approxidate(args->deepen_since);
+		packet_buf_write(&req_buf, "deepen-since %lu", max_age);
+	}
 	packet_buf_flush(&req_buf);
 	state_len = req_buf.len;
 
@@ -812,7 +818,7 @@ static struct ref *do_fetch_pack(struct fetch_pack_args *args,
 
 	if ((args->depth > 0 || is_repository_shallow()) && !server_supports("shallow"))
 		die(_("Server does not support shallow clients"));
-	if (args->depth > 0)
+	if (args->depth > 0 || args->deepen_since)
 		args->deepen = 1;
 	if (server_supports("multi_ack_detailed")) {
 		print_verbose(args, _("Server supports multi_ack_detailed"));
@@ -860,6 +866,10 @@ static struct ref *do_fetch_pack(struct fetch_pack_args *args,
 			print_verbose(args, _("Server version is %.*s"),
 				      agent_len, agent_feature);
 	}
+	if (server_supports("deepen-since"))
+		deepen_since_ok = 1;
+	else if (args->deepen_since)
+		die(_("Server does not support --shallow-since"));
 
 	if (everything_local(args, &ref, sought, nr_sought)) {
 		packet_flush(fd[1]);

fetch-pack.h

@@ -10,6 +10,7 @@ struct fetch_pack_args {
 	const char *uploadpack;
 	int unpacklimit;
 	int depth;
+	const char *deepen_since;
 	unsigned quiet:1;
 	unsigned keep_pack:1;
 	unsigned lock_pack:1;

remote-curl.c

@@ -20,6 +20,7 @@ static struct strbuf url = STRBUF_INIT;
 struct options {
 	int verbosity;
 	unsigned long depth;
+	char *deepen_since;
 	unsigned progress : 1,
 		check_self_contained_and_connected : 1,
 		cloning : 1,
@@ -60,6 +61,10 @@ static int set_option(const char *name, const char *value)
 		options.depth = v;
 		return 0;
 	}
+	else if (!strcmp(name, "deepen-since")) {
+		options.deepen_since = xstrdup(value);
+		return 0;
+	}
 	else if (!strcmp(name, "followtags")) {
 		if (!strcmp(value, "true"))
 			options.followtags = 1;
@@ -699,8 +704,8 @@ static int fetch_dumb(int nr_heads, struct ref **to_fetch)
 	char **targets = xmalloc(nr_heads * sizeof(char*));
 	int ret, i;
 
-	if (options.depth)
-		die("dumb http transport does not support --depth");
+	if (options.depth || options.deepen_since)
+		die("dumb http transport does not support shallow capabilities");
 	for (i = 0; i < nr_heads; i++)
 		targets[i] = xstrdup(oid_to_hex(&to_fetch[i]->old_oid));
 
@@ -746,6 +751,8 @@ static int fetch_git(struct discovery *heads,
 		argv_array_push(&args, "--no-progress");
 	if (options.depth)
 		argv_array_pushf(&args, "--depth=%lu", options.depth);
+	if (options.deepen_since)
+		argv_array_pushf(&args, "--shallow-since=%s", options.deepen_since);
 	argv_array_push(&args, url.buf);
 
 	for (i = 0; i < nr_heads; i++) {

transport.c

@@ -151,6 +151,9 @@ static int set_git_option(struct git_transport_options *opts,
 				die("transport: invalid depth option '%s'", value);
 		}
 		return 0;
+	} else if (!strcmp(name, TRANS_OPT_DEEPEN_SINCE)) {
+		opts->deepen_since = value;
+		return 0;
 	}
 	return 1;
 }
@@ -205,6 +208,7 @@ static int fetch_refs_via_pack(struct transport *transport,
 	args.quiet = (transport->verbose < 0);
 	args.no_progress = !transport->progress;
 	args.depth = data->options.depth;
+	args.deepen_since = data->options.deepen_since;
 	args.check_self_contained_and_connected =
 		data->options.check_self_contained_and_connected;
 	args.cloning = transport->cloning;

transport.h

@@ -13,6 +13,7 @@ struct git_transport_options {
 	unsigned self_contained_and_connected : 1;
 	unsigned update_shallow : 1;
 	int depth;
+	const char *deepen_since;
 	const char *uploadpack;
 	const char *receivepack;
 	struct push_cas_option *cas;
@@ -171,6 +172,9 @@ int transport_restrict_protocols(void);
 /* Limit the depth of the fetch if not null */
 #define TRANS_OPT_DEPTH "depth"
 
+/* Limit the depth of the fetch based on time if not null */
+#define TRANS_OPT_DEEPEN_SINCE "deepen-since"
+
 /* Aggressively fetch annotated tags if possible */
 #define TRANS_OPT_FOLLOWTAGS "followtags"