merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 207 insertions, 65 deletions

diff --git a/third_party/git/transport-helper.c b/third_party/git/transport-helper.c
index 6b05a88faf59..b573b6c730cc 100644
--- a/third_party/git/transport-helper.c
+++ b/third_party/git/transport-helper.c
@@ -9,7 +9,7 @@
 #include "string-list.h"
 #include "thread-utils.h"
 #include "sigchain.h"
-#include "argv-array.h"
+#include "strvec.h"
 #include "refs.h"
 #include "refspec.h"
 #include "transport-internal.h"
@@ -32,7 +32,18 @@ struct helper_data {
 		signed_tags : 1,
 		check_connectivity : 1,
 		no_disconnect_req : 1,
-		no_private_update : 1;
+		no_private_update : 1,
+		object_format : 1;
+
+	/*
+	 * As an optimization, the transport code may invoke fetch before
+	 * get_refs_list. If this happens, and if the transport helper doesn't
+	 * support connect or stateless_connect, we need to invoke
+	 * get_refs_list ourselves if we haven't already done so. Keep track of
+	 * whether we have invoked get_refs_list.
+	 */
+	unsigned get_refs_list_called : 1;
+
 	char *export_marks;
 	char *import_marks;
 	/* These go from remote name (as in "list") to private name */
@@ -117,17 +128,17 @@ static struct child_process *get_helper(struct transport *transport)
 	helper->in = -1;
 	helper->out = -1;
 	helper->err = 0;
-	argv_array_pushf(&helper->args, "git-remote-%s", data->name);
-	argv_array_push(&helper->args, transport->remote->name);
-	argv_array_push(&helper->args, remove_ext_force(transport->url));
-	helper->git_cmd = 0;
+	strvec_pushf(&helper->args, "remote-%s", data->name);
+	strvec_push(&helper->args, transport->remote->name);
+	strvec_push(&helper->args, remove_ext_force(transport->url));
+	helper->git_cmd = 1;
 	helper->silent_exec_failure = 1;
 
 	if (have_git_dir())
-		argv_array_pushf(&helper->env_array, "%s=%s",
-				 GIT_DIR_ENVIRONMENT, get_git_dir());
+		strvec_pushf(&helper->env_array, "%s=%s",
+			     GIT_DIR_ENVIRONMENT, get_git_dir());
 
-	helper->trace2_child_class = helper->args.argv[0]; /* "remote-<name>" */
+	helper->trace2_child_class = helper->args.v[0]; /* "remote-<name>" */
 
 	code = start_command(helper);
 	if (code < 0 && errno == ENOENT)
@@ -197,6 +208,8 @@ static struct child_process *get_helper(struct transport *transport)
 			data->import_marks = xstrdup(arg);
 		} else if (starts_with(capname, "no-private-update")) {
 			data->no_private_update = 1;
+		} else if (starts_with(capname, "object-format")) {
+			data->object_format = 1;
 		} else if (mandatory) {
 			die(_("unknown mandatory capability %s; this remote "
 			      "helper probably needs newer version of Git"),
@@ -394,15 +407,17 @@ static int fetch_with_fetch(struct transport *transport,
 	sendline(data, &buf);
 
 	while (1) {
+		const char *name;
+
 		if (recvline(data, &buf))
 			exit(128);
 
-		if (starts_with(buf.buf, "lock ")) {
-			const char *name = buf.buf + 5;
-			if (transport->pack_lockfile)
+		if (skip_prefix(buf.buf, "lock ", &name)) {
+			if (transport->pack_lockfiles.nr)
 				warning(_("%s also locked %s"), data->name, name);
 			else
-				transport->pack_lockfile = xstrdup(name);
+				string_list_append(&transport->pack_lockfiles,
+						   name);
 		}
 		else if (data->check_connectivity &&
 			 data->transport_options.check_self_contained_and_connected &&
@@ -424,12 +439,13 @@ static int get_importer(struct transport *transport, struct child_process *fasti
 	int cat_blob_fd, code;
 	child_process_init(fastimport);
 	fastimport->in = xdup(helper->out);
-	argv_array_push(&fastimport->args, "fast-import");
-	argv_array_push(&fastimport->args, debug ? "--stats" : "--quiet");
+	strvec_push(&fastimport->args, "fast-import");
+	strvec_push(&fastimport->args, "--allow-unsafe-features");
+	strvec_push(&fastimport->args, debug ? "--stats" : "--quiet");
 
 	if (data->bidi_import) {
 		cat_blob_fd = xdup(helper->in);
-		argv_array_pushf(&fastimport->args, "--cat-blob-fd=%d", cat_blob_fd);
+		strvec_pushf(&fastimport->args, "--cat-blob-fd=%d", cat_blob_fd);
 	}
 	fastimport->git_cmd = 1;
 
@@ -450,17 +466,17 @@ static int get_exporter(struct transport *transport,
 	/* we need to duplicate helper->in because we want to use it after
 	 * fastexport is done with it. */
 	fastexport->out = dup(helper->in);
-	argv_array_push(&fastexport->args, "fast-export");
-	argv_array_push(&fastexport->args, "--use-done-feature");
-	argv_array_push(&fastexport->args, data->signed_tags ?
+	strvec_push(&fastexport->args, "fast-export");
+	strvec_push(&fastexport->args, "--use-done-feature");
+	strvec_push(&fastexport->args, data->signed_tags ?
 		"--signed-tags=verbatim" : "--signed-tags=warn-strip");
 	if (data->export_marks)
-		argv_array_pushf(&fastexport->args, "--export-marks=%s.tmp", data->export_marks);
+		strvec_pushf(&fastexport->args, "--export-marks=%s.tmp", data->export_marks);
 	if (data->import_marks)
-		argv_array_pushf(&fastexport->args, "--import-marks=%s", data->import_marks);
+		strvec_pushf(&fastexport->args, "--import-marks=%s", data->import_marks);
 
 	for (i = 0; i < revlist_args->nr; i++)
-		argv_array_push(&fastexport->args, revlist_args->items[i].string);
+		strvec_push(&fastexport->args, revlist_args->items[i].string);
 
 	fastexport->git_cmd = 1;
 	return start_command(fastexport);
@@ -652,17 +668,25 @@ static int connect_helper(struct transport *transport, const char *name,
 	return 0;
 }
 
+static struct ref *get_refs_list_using_list(struct transport *transport,
+					    int for_push);
+
 static int fetch(struct transport *transport,
 		 int nr_heads, struct ref **to_fetch)
 {
 	struct helper_data *data = transport->data;
 	int i, count;
 
+	get_helper(transport);
+
 	if (process_connect(transport, 0)) {
 		do_take_over(transport);
 		return transport->vtable->fetch(transport, nr_heads, to_fetch);
 	}
 
+	if (!data->get_refs_list_called)
+		get_refs_list_using_list(transport, 0);
+
 	count = 0;
 	for (i = 0; i < nr_heads; i++)
 		if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
@@ -682,13 +706,9 @@ static int fetch(struct transport *transport,
 		set_helper_option(transport, "update-shallow", "true");
 
 	if (data->transport_options.filter_options.choice) {
-		struct strbuf expanded_filter_spec = STRBUF_INIT;
-		expand_list_objects_filter_spec(
-			&data->transport_options.filter_options,
-			&expanded_filter_spec);
-		set_helper_option(transport, "filter",
-				  expanded_filter_spec.buf);
-		strbuf_release(&expanded_filter_spec);
+		const char *spec = expand_list_objects_filter_spec(
+			&data->transport_options.filter_options);
+		set_helper_option(transport, "filter", spec);
 	}
 
 	if (data->transport_options.negotiation_tips)
@@ -703,13 +723,61 @@ static int fetch(struct transport *transport,
 	return -1;
 }
 
+struct push_update_ref_state {
+	struct ref *hint;
+	struct ref_push_report *report;
+	int new_report;
+};
+
 static int push_update_ref_status(struct strbuf *buf,
-				   struct ref **ref,
+				   struct push_update_ref_state *state,
 				   struct ref *remote_refs)
 {
 	char *refname, *msg;
 	int status, forced = 0;
 
+	if (starts_with(buf->buf, "option ")) {
+		struct object_id old_oid, new_oid;
+		const char *key, *val;
+		char *p;
+
+		if (!state->hint || !(state->report || state->new_report))
+			die(_("'option' without a matching 'ok/error' directive"));
+		if (state->new_report) {
+			if (!state->hint->report) {
+				state->hint->report = xcalloc(1, sizeof(struct ref_push_report));
+				state->report = state->hint->report;
+			} else {
+				state->report = state->hint->report;
+				while (state->report->next)
+					state->report = state->report->next;
+				state->report->next = xcalloc(1, sizeof(struct ref_push_report));
+				state->report = state->report->next;
+			}
+			state->new_report = 0;
+		}
+		key = buf->buf + 7;
+		p = strchr(key, ' ');
+		if (p)
+			*p++ = '\0';
+		val = p;
+		if (!strcmp(key, "refname"))
+			state->report->ref_name = xstrdup_or_null(val);
+		else if (!strcmp(key, "old-oid") && val &&
+			 !parse_oid_hex(val, &old_oid, &val))
+			state->report->old_oid = oiddup(&old_oid);
+		else if (!strcmp(key, "new-oid") && val &&
+			 !parse_oid_hex(val, &new_oid, &val))
+			state->report->new_oid = oiddup(&new_oid);
+		else if (!strcmp(key, "forced-update"))
+			state->report->forced_update = 1;
+		/* Not update remote namespace again. */
+		return 1;
+	}
+
+	state->report = NULL;
+	state->new_report = 0;
+
 	if (starts_with(buf->buf, "ok ")) {
 		status = REF_STATUS_OK;
 		refname = buf->buf + 3;
@@ -765,16 +833,16 @@ static int push_update_ref_status(struct strbuf *buf,
 		}
 	}
 
-	if (*ref)
-		*ref = find_ref_by_name(*ref, refname);
-	if (!*ref)
-		*ref = find_ref_by_name(remote_refs, refname);
-	if (!*ref) {
+	if (state->hint)
+		state->hint = find_ref_by_name(state->hint, refname);
+	if (!state->hint)
+		state->hint = find_ref_by_name(remote_refs, refname);
+	if (!state->hint) {
 		warning(_("helper reported unexpected status of %s"), refname);
 		return 1;
 	}
 
-	if ((*ref)->status != REF_STATUS_NONE) {
+	if (state->hint->status != REF_STATUS_NONE) {
 		/*
 		 * Earlier, the ref was marked not to be pushed, so ignore the ref
 		 * status reported by the remote helper if the latter is 'no match'.
@@ -783,9 +851,11 @@ static int push_update_ref_status(struct strbuf *buf,
 			return 1;
 	}
 
-	(*ref)->status = status;
-	(*ref)->forced_update |= forced;
-	(*ref)->remote_status = msg;
+	if (status == REF_STATUS_OK)
+		state->new_report = 1;
+	state->hint->status = status;
+	state->hint->forced_update |= forced;
+	state->hint->remote_status = msg;
 	return !(status == REF_STATUS_OK);
 }
 
@@ -793,37 +863,57 @@ static int push_update_refs_status(struct helper_data *data,
 				    struct ref *remote_refs,
 				    int flags)
 {
+	struct ref *ref;
+	struct ref_push_report *report;
 	struct strbuf buf = STRBUF_INIT;
-	struct ref *ref = remote_refs;
-	int ret = 0;
+	struct push_update_ref_state state = { remote_refs, NULL, 0 };
 
 	for (;;) {
-		char *private;
-
 		if (recvline(data, &buf)) {
-			ret = 1;
-			break;
+			strbuf_release(&buf);
+			return 1;
 		}
-
 		if (!buf.len)
 			break;
+		push_update_ref_status(&buf, &state, remote_refs);
+	}
+	strbuf_release(&buf);
 
-		if (push_update_ref_status(&buf, &ref, remote_refs))
-			continue;
+	if (flags & TRANSPORT_PUSH_DRY_RUN || !data->rs.nr || data->no_private_update)
+		return 0;
 
-		if (flags & TRANSPORT_PUSH_DRY_RUN || !data->rs.nr || data->no_private_update)
-			continue;
+	/* propagate back the update to the remote namespace */
+	for (ref = remote_refs; ref; ref = ref->next) {
+		char *private;
 
-		/* propagate back the update to the remote namespace */
-		private = apply_refspecs(&data->rs, ref->name);
-		if (!private)
+		if (ref->status != REF_STATUS_OK)
 			continue;
-		update_ref("update by helper", private, &ref->new_oid, NULL,
-			   0, 0);
-		free(private);
+
+		if (!ref->report) {
+			private = apply_refspecs(&data->rs, ref->name);
+			if (!private)
+				continue;
+			update_ref("update by helper", private, &(ref->new_oid),
+				   NULL, 0, 0);
+			free(private);
+		} else {
+			for (report = ref->report; report; report = report->next) {
+				private = apply_refspecs(&data->rs,
+							 report->ref_name
+							 ? report->ref_name
+							 : ref->name);
+				if (!private)
+					continue;
+				update_ref("update by helper", private,
+					   report->new_oid
+					   ? report->new_oid
+					   : &(ref->new_oid),
+					   NULL, 0, 0);
+				free(private);
+			}
+		}
 	}
-	strbuf_release(&buf);
-	return ret;
+	return 0;
 }
 
 static void set_common_push_options(struct transport *transport,
@@ -840,6 +930,10 @@ static void set_common_push_options(struct transport *transport,
 			die(_("helper %s does not support --signed=if-asked"), name);
 	}
 
+	if (flags & TRANSPORT_PUSH_ATOMIC)
+		if (set_helper_option(transport, TRANS_OPT_ATOMIC, "true") != 0)
+			die(_("helper %s does not support --atomic"), name);
+
 	if (flags & TRANSPORT_PUSH_OPTIONS) {
 		struct string_list_item *item;
 		for_each_string_list_item(item, transport->push_options)
@@ -874,6 +968,7 @@ static int push_refs_with_push(struct transport *transport,
 		case REF_STATUS_REJECT_STALE:
 		case REF_STATUS_REJECT_ALREADY_EXISTS:
 			if (atomic) {
+				reject_atomic_push(remote_refs, mirror);
 				string_list_clear(&cas_options, 0);
 				return 0;
 			} else
@@ -1025,7 +1120,7 @@ static int push_refs(struct transport *transport,
 	if (!remote_refs) {
 		fprintf(stderr,
 			_("No refs in common and none specified; doing nothing.\n"
-			  "Perhaps you should specify a branch such as 'master'.\n"));
+			  "Perhaps you should specify a branch.\n"));
 		return 0;
 	}
 
@@ -1057,7 +1152,20 @@ static int has_attribute(const char *attrs, const char *attr)
 }
 
 static struct ref *get_refs_list(struct transport *transport, int for_push,
-				 const struct argv_array *ref_prefixes)
+				 const struct strvec *ref_prefixes)
+{
+	get_helper(transport);
+
+	if (process_connect(transport, for_push)) {
+		do_take_over(transport);
+		return transport->vtable->get_refs_list(transport, for_push, ref_prefixes);
+	}
+
+	return get_refs_list_using_list(transport, for_push);
+}
+
+static struct ref *get_refs_list_using_list(struct transport *transport,
+					    int for_push)
 {
 	struct helper_data *data = transport->data;
 	struct child_process *helper;
@@ -1066,11 +1174,13 @@ static struct ref *get_refs_list(struct transport *transport, int for_push,
 	struct ref *posn;
 	struct strbuf buf = STRBUF_INIT;
 
+	data->get_refs_list_called = 1;
 	helper = get_helper(transport);
 
-	if (process_connect(transport, for_push)) {
-		do_take_over(transport);
-		return transport->vtable->get_refs_list(transport, for_push, ref_prefixes);
+	if (data->object_format) {
+		write_str_in_full(helper->in, "option object-format\n");
+		if (recvline(data, &buf) || strcmp(buf.buf, "ok"))
+			exit(128);
 	}
 
 	if (data->push && for_push)
@@ -1085,6 +1195,17 @@ static struct ref *get_refs_list(struct transport *transport, int for_push,
 
 		if (!*buf.buf)
 			break;
+		else if (buf.buf[0] == ':') {
+			const char *value;
+			if (skip_prefix(buf.buf, ":object-format ", &value)) {
+				int algo = hash_algo_by_name(value);
+				if (algo == GIT_HASH_UNKNOWN)
+					die(_("unsupported object format '%s'"),
+					    value);
+				transport->hash_algo = &hash_algos[algo];
+			}
+			continue;
+		}
 
 		eov = strchr(buf.buf, ' ');
 		if (!eov)
@@ -1097,7 +1218,7 @@ static struct ref *get_refs_list(struct transport *transport, int for_push,
 		if (buf.buf[0] == '@')
 			(*tail)->symref = xstrdup(buf.buf + 1);
 		else if (buf.buf[0] != '?')
-			get_oid_hex(buf.buf, &(*tail)->old_oid);
+			get_oid_hex_algop(buf.buf, &(*tail)->old_oid, transport->hash_algo);
 		if (eon) {
 			if (has_attribute(eon + 1, "unchanged")) {
 				(*tail)->status |= REF_STATUS_UPTODATE;
@@ -1119,7 +1240,6 @@ static struct ref *get_refs_list(struct transport *transport, int for_push,
 }
 
 static struct transport_vtable vtable = {
-	0,
 	set_helper_option,
 	get_refs_list,
 	fetch,
@@ -1460,3 +1580,25 @@ int bidirectional_transfer_loop(int input, int output)
 
 	return tloop_spawnwait_tasks(&state);
 }
+
+void reject_atomic_push(struct ref *remote_refs, int mirror_mode)
+{
+	struct ref *ref;
+
+	/* Mark other refs as failed */
+	for (ref = remote_refs; ref; ref = ref->next) {
+		if (!ref->peer_ref && !mirror_mode)
+			continue;
+
+		switch (ref->status) {
+		case REF_STATUS_NONE:
+		case REF_STATUS_OK:
+		case REF_STATUS_EXPECTING_REPORT:
+			ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
+			continue;
+		default:
+			break; /* do nothing */
+		}
+	}
+	return;
+}