1 files changed, 300 insertions, 125 deletions

diff --git a/transport-helper.c b/transport-helper.c
index 6f227e253b..a6bff8b308 100644
--- a/transport-helper.c
+++ b/transport-helper.c
@@ -5,10 +5,12 @@
 #include "commit.h"
 #include "diff.h"
 #include "revision.h"
-#include "quote.h"
 #include "remote.h"
 #include "string-list.h"
 #include "thread-utils.h"
+#include "sigchain.h"
+#include "argv-array.h"
+#include "refs.h"
 
 static int debug;
 
@@ -18,11 +20,15 @@ struct helper_data {
 	FILE *out;
 	unsigned fetch : 1,
 		import : 1,
+		bidi_import : 1,
 		export : 1,
 		option : 1,
 		push : 1,
 		connect : 1,
-		no_disconnect_req : 1;
+		signed_tags : 1,
+		check_connectivity : 1,
+		no_disconnect_req : 1,
+		no_private_update : 1;
 	char *export_marks;
 	char *import_marks;
 	/* These go from remote name (as in "list") to private name */
@@ -43,15 +49,15 @@ static void sendline(struct helper_data *helper, struct strbuf *buffer)
 		die_errno("Full write to remote helper failed");
 }
 
-static int recvline_fh(FILE *helper, struct strbuf *buffer)
+static int recvline_fh(FILE *helper, struct strbuf *buffer, const char *name)
 {
 	strbuf_reset(buffer);
 	if (debug)
 		fprintf(stderr, "Debug: Remote helper: Waiting...\n");
-	if (strbuf_getline(buffer, helper, '\n') == EOF) {
+	if (strbuf_getline(buffer, helper) == EOF) {
 		if (debug)
 			fprintf(stderr, "Debug: Remote helper quit.\n");
-		exit(128);
+		return 1;
 	}
 
 	if (debug)
@@ -61,13 +67,7 @@ static int recvline_fh(FILE *helper, struct strbuf *buffer)
 
 static int recvline(struct helper_data *helper, struct strbuf *buffer)
 {
-	return recvline_fh(helper->out, buffer);
-}
-
-static void xchgline(struct helper_data *helper, struct strbuf *buffer)
-{
-	sendline(helper, buffer);
-	recvline(helper, buffer);
+	return recvline_fh(helper->out, buffer, helper->name);
 }
 
 static void write_constant(int fd, const char *str)
@@ -97,6 +97,8 @@ static void do_take_over(struct transport *transport)
 	free(data);
 }
 
+static void standard_options(struct transport *t);
+
 static struct child_process *get_helper(struct transport *transport)
 {
 	struct helper_data *data = transport->data;
@@ -107,30 +109,23 @@ static struct child_process *get_helper(struct transport *transport)
 	int refspec_alloc = 0;
 	int duped;
 	int code;
-	char git_dir_buf[sizeof(GIT_DIR_ENVIRONMENT) + PATH_MAX + 1];
-	const char *helper_env[] = {
-		git_dir_buf,
-		NULL
-	};
-
 
 	if (data->helper)
 		return data->helper;
 
-	helper = xcalloc(1, sizeof(*helper));
+	helper = xmalloc(sizeof(*helper));
+	child_process_init(helper);
 	helper->in = -1;
 	helper->out = -1;
 	helper->err = 0;
-	helper->argv = xcalloc(4, sizeof(*helper->argv));
-	strbuf_addf(&buf, "git-remote-%s", data->name);
-	helper->argv[0] = strbuf_detach(&buf, NULL);
-	helper->argv[1] = transport->remote->name;
-	helper->argv[2] = remove_ext_force(transport->url);
+	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;
 	helper->silent_exec_failure = 1;
 
-	snprintf(git_dir_buf, sizeof(git_dir_buf), "%s=%s", GIT_DIR_ENVIRONMENT, get_git_dir());
-	helper->env = helper_env;
+	argv_array_pushf(&helper->env_array, "%s=%s", GIT_DIR_ENVIRONMENT,
+			 get_git_dir());
 
 	code = start_command(helper);
 	if (code < 0 && errno == ENOENT)
@@ -142,7 +137,8 @@ static struct child_process *get_helper(struct transport *transport)
 	data->no_disconnect_req = 0;
 
 	/*
-	 * Open the output as FILE* so strbuf_getline() can be used.
+	 * Open the output as FILE* so strbuf_getline_*() family of
+	 * functions can be used.
 	 * Do this with duped fd because fclose() will close the fd,
 	 * and stuff like taking over will require the fd to remain.
 	 */
@@ -154,9 +150,10 @@ static struct child_process *get_helper(struct transport *transport)
 	write_constant(helper->in, "capabilities\n");
 
 	while (1) {
-		const char *capname;
+		const char *capname, *arg;
 		int mandatory = 0;
-		recvline(data, &buf);
+		if (recvline(data, &buf))
+			exit(128);
 
 		if (!*buf.buf)
 			break;
@@ -177,28 +174,30 @@ static struct child_process *get_helper(struct transport *transport)
 			data->push = 1;
 		else if (!strcmp(capname, "import"))
 			data->import = 1;
+		else if (!strcmp(capname, "bidi-import"))
+			data->bidi_import = 1;
 		else if (!strcmp(capname, "export"))
 			data->export = 1;
-		else if (!data->refspecs && !prefixcmp(capname, "refspec ")) {
+		else if (!strcmp(capname, "check-connectivity"))
+			data->check_connectivity = 1;
+		else if (!data->refspecs && skip_prefix(capname, "refspec ", &arg)) {
 			ALLOC_GROW(refspecs,
 				   refspec_nr + 1,
 				   refspec_alloc);
-			refspecs[refspec_nr++] = xstrdup(capname + strlen("refspec "));
+			refspecs[refspec_nr++] = xstrdup(arg);
 		} else if (!strcmp(capname, "connect")) {
 			data->connect = 1;
-		} else if (!prefixcmp(capname, "export-marks ")) {
-			struct strbuf arg = STRBUF_INIT;
-			strbuf_addstr(&arg, "--export-marks=");
-			strbuf_addstr(&arg, capname + strlen("export-marks "));
-			data->export_marks = strbuf_detach(&arg, NULL);
-		} else if (!prefixcmp(capname, "import-marks")) {
-			struct strbuf arg = STRBUF_INIT;
-			strbuf_addstr(&arg, "--import-marks=");
-			strbuf_addstr(&arg, capname + strlen("import-marks "));
-			data->import_marks = strbuf_detach(&arg, NULL);
+		} else if (!strcmp(capname, "signed-tags")) {
+			data->signed_tags = 1;
+		} else if (skip_prefix(capname, "export-marks ", &arg)) {
+			data->export_marks = xstrdup(arg);
+		} else if (skip_prefix(capname, "import-marks ", &arg)) {
+			data->import_marks = xstrdup(arg);
+		} else if (starts_with(capname, "no-private-update")) {
+			data->no_private_update = 1;
 		} else if (mandatory) {
 			die("Unknown mandatory capability %s. This remote "
-			    "helper probably needs newer version of Git.\n",
+			    "helper probably needs newer version of Git.",
 			    capname);
 		}
 	}
@@ -206,36 +205,42 @@ static struct child_process *get_helper(struct transport *transport)
 		int i;
 		data->refspec_nr = refspec_nr;
 		data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
-		for (i = 0; i < refspec_nr; i++) {
+		for (i = 0; i < refspec_nr; i++)
 			free((char *)refspecs[i]);
-		}
 		free(refspecs);
+	} else if (data->import || data->bidi_import || data->export) {
+		warning("This remote helper should implement refspec capability.");
 	}
 	strbuf_release(&buf);
 	if (debug)
 		fprintf(stderr, "Debug: Capabilities complete.\n");
+	standard_options(transport);
 	return data->helper;
 }
 
 static int disconnect_helper(struct transport *transport)
 {
 	struct helper_data *data = transport->data;
-	struct strbuf buf = STRBUF_INIT;
 	int res = 0;
 
 	if (data->helper) {
 		if (debug)
 			fprintf(stderr, "Debug: Disconnecting.\n");
 		if (!data->no_disconnect_req) {
-			strbuf_addf(&buf, "\n");
-			sendline(data, &buf);
+			/*
+			 * Ignore write errors; there's nothing we can do,
+			 * since we're about to close the pipe anyway. And the
+			 * most likely error is EPIPE due to the helper dying
+			 * to report an error itself.
+			 */
+			sigchain_push(SIGPIPE, SIG_IGN);
+			xwrite(data->helper->in, "\n", 1);
+			sigchain_pop(SIGPIPE);
 		}
 		close(data->helper->in);
 		close(data->helper->out);
 		fclose(data->out);
 		res = finish_command(data->helper);
-		free((char *)data->helper->argv[0]);
-		free(data->helper->argv);
 		free(data->helper);
 		data->helper = NULL;
 	}
@@ -248,10 +253,11 @@ static const char *unsupported_options[] = {
 	TRANS_OPT_THIN,
 	TRANS_OPT_KEEP
 	};
+
 static const char *boolean_options[] = {
 	TRANS_OPT_THIN,
 	TRANS_OPT_KEEP,
-	TRANS_OPT_FOLLOWTAGS
+	TRANS_OPT_FOLLOWTAGS,
 	};
 
 static int set_helper_option(struct transport *transport,
@@ -285,11 +291,13 @@ static int set_helper_option(struct transport *transport,
 		quote_c_style(value, &buf, NULL, 0);
 	strbuf_addch(&buf, '\n');
 
-	xchgline(data, &buf);
+	sendline(data, &buf);
+	if (recvline(data, &buf))
+		exit(128);
 
 	if (!strcmp(buf.buf, "ok"))
 		ret = 0;
-	else if (!prefixcmp(buf.buf, "error")) {
+	else if (starts_with(buf.buf, "error")) {
 		ret = -1;
 	} else if (!strcmp(buf.buf, "unsupported"))
 		ret = 1;
@@ -333,30 +341,34 @@ static int fetch_with_fetch(struct transport *transport,
 	int i;
 	struct strbuf buf = STRBUF_INIT;
 
-	standard_options(transport);
-
 	for (i = 0; i < nr_heads; i++) {
 		const struct ref *posn = to_fetch[i];
 		if (posn->status & REF_STATUS_UPTODATE)
 			continue;
 
 		strbuf_addf(&buf, "fetch %s %s\n",
-			    sha1_to_hex(posn->old_sha1), posn->name);
+			    oid_to_hex(&posn->old_oid),
+			    posn->symref ? posn->symref : posn->name);
 	}
 
 	strbuf_addch(&buf, '\n');
 	sendline(data, &buf);
 
 	while (1) {
-		recvline(data, &buf);
+		if (recvline(data, &buf))
+			exit(128);
 
-		if (!prefixcmp(buf.buf, "lock ")) {
+		if (starts_with(buf.buf, "lock ")) {
 			const char *name = buf.buf + 5;
 			if (transport->pack_lockfile)
 				warning("%s also locked %s", data->name, name);
 			else
 				transport->pack_lockfile = xstrdup(name);
 		}
+		else if (data->check_connectivity &&
+			 data->transport_options.check_self_contained_and_connected &&
+			 !strcmp(buf.buf, "connectivity-ok"))
+			data->transport_options.self_contained_and_connected = 1;
 		else if (!buf.len)
 			break;
 		else
@@ -369,14 +381,21 @@ static int fetch_with_fetch(struct transport *transport,
 static int get_importer(struct transport *transport, struct child_process *fastimport)
 {
 	struct child_process *helper = get_helper(transport);
-	memset(fastimport, 0, sizeof(*fastimport));
+	struct helper_data *data = transport->data;
+	int cat_blob_fd, code;
+	child_process_init(fastimport);
 	fastimport->in = helper->out;
-	fastimport->argv = xcalloc(5, sizeof(*fastimport->argv));
-	fastimport->argv[0] = "fast-import";
-	fastimport->argv[1] = "--quiet";
+	argv_array_push(&fastimport->args, "fast-import");
+	argv_array_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);
+	}
 	fastimport->git_cmd = 1;
-	return start_command(fastimport);
+
+	code = start_command(fastimport);
+	return code;
 }
 
 static int get_exporter(struct transport *transport,
@@ -385,22 +404,24 @@ static int get_exporter(struct transport *transport,
 {
 	struct helper_data *data = transport->data;
 	struct child_process *helper = get_helper(transport);
-	int argc = 0, i;
-	memset(fastexport, 0, sizeof(*fastexport));
+	int i;
+
+	child_process_init(fastexport);
 
 	/* we need to duplicate helper->in because we want to use it after
 	 * fastexport is done with it. */
 	fastexport->out = dup(helper->in);
-	fastexport->argv = xcalloc(5 + revlist_args->nr, sizeof(*fastexport->argv));
-	fastexport->argv[argc++] = "fast-export";
-	fastexport->argv[argc++] = "--use-done-feature";
+	argv_array_push(&fastexport->args, "fast-export");
+	argv_array_push(&fastexport->args, "--use-done-feature");
+	argv_array_push(&fastexport->args, data->signed_tags ?
+		"--signed-tags=verbatim" : "--signed-tags=warn-strip");
 	if (data->export_marks)
-		fastexport->argv[argc++] = data->export_marks;
+		argv_array_pushf(&fastexport->args, "--export-marks=%s.tmp", data->export_marks);
 	if (data->import_marks)
-		fastexport->argv[argc++] = data->import_marks;
+		argv_array_pushf(&fastexport->args, "--import-marks=%s", data->import_marks);
 
 	for (i = 0; i < revlist_args->nr; i++)
-		fastexport->argv[argc++] = revlist_args->items[i].string;
+		argv_array_push(&fastexport->args, revlist_args->items[i].string);
 
 	fastexport->git_cmd = 1;
 	return start_command(fastexport);
@@ -425,29 +446,52 @@ static int fetch_with_import(struct transport *transport,
 		if (posn->status & REF_STATUS_UPTODATE)
 			continue;
 
-		strbuf_addf(&buf, "import %s\n", posn->name);
+		strbuf_addf(&buf, "import %s\n",
+			    posn->symref ? posn->symref : posn->name);
 		sendline(data, &buf);
 		strbuf_reset(&buf);
 	}
 
 	write_constant(data->helper->in, "\n");
+	/*
+	 * remote-helpers that advertise the bidi-import capability are required to
+	 * buffer the complete batch of import commands until this newline before
+	 * sending data to fast-import.
+	 * These helpers read back data from fast-import on their stdin, which could
+	 * be mixed with import commands, otherwise.
+	 */
 
 	if (finish_command(&fastimport))
 		die("Error while running fast-import");
-	free(fastimport.argv);
-	fastimport.argv = NULL;
 
+	/*
+	 * The fast-import stream of a remote helper that advertises
+	 * the "refspec" capability writes to the refs named after the
+	 * right hand side of the first refspec matching each ref we
+	 * were fetching.
+	 *
+	 * (If no "refspec" capability was specified, for historical
+	 * reasons we default to the equivalent of *:*.)
+	 *
+	 * Store the result in to_fetch[i].old_sha1.  Callers such
+	 * as "git fetch" can use the value to write feedback to the
+	 * terminal, populate FETCH_HEAD, and determine what new value
+	 * should be written to peer_ref if the update is a
+	 * fast-forward or this is a forced update.
+	 */
 	for (i = 0; i < nr_heads; i++) {
-		char *private;
+		char *private, *name;
 		posn = to_fetch[i];
 		if (posn->status & REF_STATUS_UPTODATE)
 			continue;
+		name = posn->symref ? posn->symref : posn->name;
 		if (data->refspecs)
-			private = apply_refspecs(data->refspecs, data->refspec_nr, posn->name);
+			private = apply_refspecs(data->refspecs, data->refspec_nr, name);
 		else
-			private = xstrdup(posn->name);
+			private = xstrdup(name);
 		if (private) {
-			read_ref(private, posn->old_sha1);
+			if (read_ref(private, posn->old_oid.hash) < 0)
+				die("Could not read ref %s", private);
 			free(private);
 		}
 	}
@@ -496,7 +540,9 @@ static int process_connect_service(struct transport *transport,
 		goto exit;
 
 	sendline(data, &cmdbuf);
-	recvline_fh(input, &cmdbuf);
+	if (recvline_fh(input, &cmdbuf, name))
+		exit(128);
+
 	if (!strcmp(cmdbuf.buf, "")) {
 		data->no_disconnect_req = 1;
 		if (debug)
@@ -569,6 +615,16 @@ static int fetch(struct transport *transport,
 	if (!count)
 		return 0;
 
+	if (data->check_connectivity &&
+	    data->transport_options.check_self_contained_and_connected)
+		set_helper_option(transport, "check-connectivity", "true");
+
+	if (transport->cloning)
+		set_helper_option(transport, "cloning", "true");
+
+	if (data->transport_options.update_shallow)
+		set_helper_option(transport, "update-shallow", "true");
+
 	if (data->fetch)
 		return fetch_with_fetch(transport, nr_heads, to_fetch);
 
@@ -578,21 +634,21 @@ static int fetch(struct transport *transport,
 	return -1;
 }
 
-static void push_update_ref_status(struct strbuf *buf,
+static int push_update_ref_status(struct strbuf *buf,
 				   struct ref **ref,
 				   struct ref *remote_refs)
 {
 	char *refname, *msg;
-	int status;
+	int status, forced = 0;
 
-	if (!prefixcmp(buf->buf, "ok ")) {
+	if (starts_with(buf->buf, "ok ")) {
 		status = REF_STATUS_OK;
 		refname = buf->buf + 3;
-	} else if (!prefixcmp(buf->buf, "error ")) {
+	} else if (starts_with(buf->buf, "error ")) {
 		status = REF_STATUS_REMOTE_REJECT;
 		refname = buf->buf + 6;
 	} else
-		die("expected ok/error, helper said '%s'\n", buf->buf);
+		die("expected ok/error, helper said '%s'", buf->buf);
 
 	msg = strchr(refname, ' ');
 	if (msg) {
@@ -621,6 +677,31 @@ static void push_update_ref_status(struct strbuf *buf,
 			free(msg);
 			msg = NULL;
 		}
+		else if (!strcmp(msg, "already exists")) {
+			status = REF_STATUS_REJECT_ALREADY_EXISTS;
+			free(msg);
+			msg = NULL;
+		}
+		else if (!strcmp(msg, "fetch first")) {
+			status = REF_STATUS_REJECT_FETCH_FIRST;
+			free(msg);
+			msg = NULL;
+		}
+		else if (!strcmp(msg, "needs force")) {
+			status = REF_STATUS_REJECT_NEEDS_FORCE;
+			free(msg);
+			msg = NULL;
+		}
+		else if (!strcmp(msg, "stale info")) {
+			status = REF_STATUS_REJECT_STALE;
+			free(msg);
+			msg = NULL;
+		}
+		else if (!strcmp(msg, "forced update")) {
+			forced = 1;
+			free(msg);
+			msg = NULL;
+		}
 	}
 
 	if (*ref)
@@ -629,7 +710,7 @@ static void push_update_ref_status(struct strbuf *buf,
 		*ref = find_ref_by_name(remote_refs, refname);
 	if (!*ref) {
 		warning("helper reported unexpected status of %s", refname);
-		return;
+		return 1;
 	}
 
 	if ((*ref)->status != REF_STATUS_NONE) {
@@ -638,36 +719,76 @@ static void push_update_ref_status(struct strbuf *buf,
 		 * status reported by the remote helper if the latter is 'no match'.
 		 */
 		if (status == REF_STATUS_NONE)
-			return;
+			return 1;
 	}
 
 	(*ref)->status = status;
+	(*ref)->forced_update |= forced;
 	(*ref)->remote_status = msg;
+	return !(status == REF_STATUS_OK);
 }
 
-static void push_update_refs_status(struct helper_data *data,
-				    struct ref *remote_refs)
+static int push_update_refs_status(struct helper_data *data,
+				    struct ref *remote_refs,
+				    int flags)
 {
 	struct strbuf buf = STRBUF_INIT;
 	struct ref *ref = remote_refs;
+	int ret = 0;
+
 	for (;;) {
-		recvline(data, &buf);
+		char *private;
+
+		if (recvline(data, &buf)) {
+			ret = 1;
+			break;
+		}
+
 		if (!buf.len)
 			break;
 
-		push_update_ref_status(&buf, &ref, remote_refs);
+		if (push_update_ref_status(&buf, &ref, remote_refs))
+			continue;
+
+		if (flags & TRANSPORT_PUSH_DRY_RUN || !data->refspecs || data->no_private_update)
+			continue;
+
+		/* propagate back the update to the remote namespace */
+		private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
+		if (!private)
+			continue;
+		update_ref("update by helper", private, ref->new_oid.hash, NULL, 0, 0);
+		free(private);
 	}
 	strbuf_release(&buf);
+	return ret;
+}
+
+static void set_common_push_options(struct transport *transport,
+				   const char *name, int flags)
+{
+	if (flags & TRANSPORT_PUSH_DRY_RUN) {
+		if (set_helper_option(transport, "dry-run", "true") != 0)
+			die("helper %s does not support dry-run", name);
+	} else if (flags & TRANSPORT_PUSH_CERT_ALWAYS) {
+		if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "true") != 0)
+			die("helper %s does not support --signed", name);
+	} else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED) {
+		if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "if-asked") != 0)
+			die("helper %s does not support --signed=if-asked", name);
+	}
 }
 
 static int push_refs_with_push(struct transport *transport,
-		struct ref *remote_refs, int flags)
+			       struct ref *remote_refs, int flags)
 {
 	int force_all = flags & TRANSPORT_PUSH_FORCE;
 	int mirror = flags & TRANSPORT_PUSH_MIRROR;
 	struct helper_data *data = transport->data;
 	struct strbuf buf = STRBUF_INIT;
 	struct ref *ref;
+	struct string_list cas_options = STRING_LIST_INIT_DUP;
+	struct string_list_item *cas_option;
 
 	get_helper(transport);
 	if (!data->push)
@@ -680,6 +801,8 @@ static int push_refs_with_push(struct transport *transport,
 		/* Check for statuses set by set_ref_status_for_push() */
 		switch (ref->status) {
 		case REF_STATUS_REJECT_NONFASTFORWARD:
+		case REF_STATUS_REJECT_STALE:
+		case REF_STATUS_REJECT_ALREADY_EXISTS:
 		case REF_STATUS_UPTODATE:
 			continue;
 		default:
@@ -696,28 +819,40 @@ static int push_refs_with_push(struct transport *transport,
 			if (ref->peer_ref)
 				strbuf_addstr(&buf, ref->peer_ref->name);
 			else
-				strbuf_addstr(&buf, sha1_to_hex(ref->new_sha1));
+				strbuf_addstr(&buf, oid_to_hex(&ref->new_oid));
 		}
 		strbuf_addch(&buf, ':');
 		strbuf_addstr(&buf, ref->name);
 		strbuf_addch(&buf, '\n');
+
+		/*
+		 * The "--force-with-lease" options without explicit
+		 * values to expect have already been expanded into
+		 * the ref->old_oid_expect[] field; we can ignore
+		 * transport->smart_options->cas altogether and instead
+		 * can enumerate them from the refs.
+		 */
+		if (ref->expect_old_sha1) {
+			struct strbuf cas = STRBUF_INIT;
+			strbuf_addf(&cas, "%s:%s",
+				    ref->name, oid_to_hex(&ref->old_oid_expect));
+			string_list_append(&cas_options, strbuf_detach(&cas, NULL));
+		}
 	}
-	if (buf.len == 0)
+	if (buf.len == 0) {
+		string_list_clear(&cas_options, 0);
 		return 0;
-
-	standard_options(transport);
-
-	if (flags & TRANSPORT_PUSH_DRY_RUN) {
-		if (set_helper_option(transport, "dry-run", "true") != 0)
-			die("helper %s does not support dry-run", data->name);
 	}
 
+	for_each_string_list_item(cas_option, &cas_options)
+		set_helper_option(transport, "cas", cas_option->string);
+	set_common_push_options(transport, data->name, flags);
+
 	strbuf_addch(&buf, '\n');
 	sendline(data, &buf);
 	strbuf_release(&buf);
 
-	push_update_refs_status(data, remote_refs);
-	return 0;
+	return push_update_refs_status(data, remote_refs, flags);
 }
 
 static int push_refs_with_export(struct transport *transport,
@@ -726,43 +861,77 @@ static int push_refs_with_export(struct transport *transport,
 	struct ref *ref;
 	struct child_process *helper, exporter;
 	struct helper_data *data = transport->data;
-	struct string_list revlist_args = STRING_LIST_INIT_NODUP;
+	struct string_list revlist_args = STRING_LIST_INIT_DUP;
 	struct strbuf buf = STRBUF_INIT;
 
+	if (!data->refspecs)
+		die("remote-helper doesn't support push; refspec needed");
+
+	set_common_push_options(transport, data->name, flags);
+	if (flags & TRANSPORT_PUSH_FORCE) {
+		if (set_helper_option(transport, "force", "true") != 0)
+			warning("helper %s does not support 'force'", data->name);
+	}
+
 	helper = get_helper(transport);
 
 	write_constant(helper->in, "export\n");
 
-	strbuf_reset(&buf);
-
 	for (ref = remote_refs; ref; ref = ref->next) {
 		char *private;
-		unsigned char sha1[20];
+		struct object_id oid;
 
-		if (!data->refspecs)
-			continue;
 		private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
-		if (private && !get_sha1(private, sha1)) {
+		if (private && !get_sha1(private, oid.hash)) {
 			strbuf_addf(&buf, "^%s", private);
 			string_list_append(&revlist_args, strbuf_detach(&buf, NULL));
+			oidcpy(&ref->old_oid, &oid);
 		}
 		free(private);
 
-		if (ref->deletion) {
-			die("remote-helpers do not support ref deletion");
+		if (ref->peer_ref) {
+			if (strcmp(ref->name, ref->peer_ref->name)) {
+				if (!ref->deletion) {
+					const char *name;
+					int flag;
+
+					/* Follow symbolic refs (mainly for HEAD). */
+					name = resolve_ref_unsafe(
+						 ref->peer_ref->name,
+						 RESOLVE_REF_READING,
+						 oid.hash, &flag);
+					if (!name || !(flag & REF_ISSYMREF))
+						name = ref->peer_ref->name;
+
+					strbuf_addf(&buf, "%s:%s", name, ref->name);
+				} else
+					strbuf_addf(&buf, ":%s", ref->name);
+
+				string_list_append(&revlist_args, "--refspec");
+				string_list_append(&revlist_args, buf.buf);
+				strbuf_release(&buf);
+			}
+			if (!ref->deletion)
+				string_list_append(&revlist_args, ref->peer_ref->name);
 		}
-
-		if (ref->peer_ref)
-			string_list_append(&revlist_args, ref->peer_ref->name);
-
 	}
 
 	if (get_exporter(transport, &exporter, &revlist_args))
 		die("Couldn't run fast-export");
 
+	string_list_clear(&revlist_args, 1);
+
 	if (finish_command(&exporter))
 		die("Error while running fast-export");
-	push_update_refs_status(data, remote_refs);
+	if (push_update_refs_status(data, remote_refs, flags))
+		return 1;
+
+	if (data->export_marks) {
+		strbuf_addf(&buf, "%s.tmp", data->export_marks);
+		rename(buf.buf, data->export_marks);
+		strbuf_release(&buf);
+	}
+
 	return 0;
 }
 
@@ -831,7 +1000,8 @@ static struct ref *get_refs_list(struct transport *transport, int for_push)
 
 	while (1) {
 		char *eov, *eon;
-		recvline(data, &buf);
+		if (recvline(data, &buf))
+			exit(128);
 
 		if (!*buf.buf)
 			break;
@@ -847,11 +1017,14 @@ 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_sha1_hex(buf.buf, (*tail)->old_sha1);
+			get_oid_hex(buf.buf, &(*tail)->old_oid);
 		if (eon) {
 			if (has_attribute(eon + 1, "unchanged")) {
 				(*tail)->status |= REF_STATUS_UPTODATE;
-				read_ref((*tail)->name, (*tail)->old_sha1);
+				if (read_ref((*tail)->name,
+					     (*tail)->old_oid.hash) < 0)
+					die(N_("Could not read ref %s"),
+					    (*tail)->name);
 			}
 		}
 		tail = &((*tail)->next);
@@ -868,9 +1041,11 @@ static struct ref *get_refs_list(struct transport *transport, int for_push)
 
 int transport_helper_init(struct transport *transport, const char *name)
 {
-	struct helper_data *data = xcalloc(sizeof(*data), 1);
+	struct helper_data *data = xcalloc(1, sizeof(*data));
 	data->name = name;
 
+	transport_check_allowed(name);
+
 	if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
 		debug = 1;
 
@@ -894,6 +1069,7 @@ int transport_helper_init(struct transport *transport, const char *name)
 #define PBUFFERSIZE 8192
 
 /* Print bidirectional transfer loop debug message. */
+__attribute__((format (printf, 1, 2)))
 static void transfer_debug(const char *fmt, ...)
 {
 	va_list args;
@@ -935,7 +1111,7 @@ struct unidirectional_transfer {
 	int src_is_sock;
 	/* Is destination socket? */
 	int dest_is_sock;
-	/* Transfer state (TRANSFERING/FLUSHING/FINISHED) */
+	/* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
 	int state;
 	/* Buffer. */
 	char buf[BUFFERSIZE];
@@ -979,7 +1155,7 @@ static int udt_do_read(struct unidirectional_transfer *t)
 		return -1;
 	} else if (bytes == 0) {
 		transfer_debug("%s EOF (with %i bytes in buffer)",
-			t->src_name, t->bufuse);
+			t->src_name, (int)t->bufuse);
 		t->state = SSTATE_FLUSHING;
 	} else if (bytes > 0) {
 		t->bufuse += bytes;
@@ -1000,9 +1176,8 @@ static int udt_do_write(struct unidirectional_transfer *t)
 		return 0;	/* Nothing to write. */
 
 	transfer_debug("%s is writable", t->dest_name);
-	bytes = write(t->dest, t->buf, t->bufuse);
-	if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
-		errno != EINTR) {
+	bytes = xwrite(t->dest, t->buf, t->bufuse);
+	if (bytes < 0 && errno != EWOULDBLOCK) {
 		error("write(%s) failed: %s", t->dest_name, strerror(errno));
 		return -1;
 	} else if (bytes > 0) {
@@ -1043,7 +1218,7 @@ static void *udt_copy_task_routine(void *udt)
 #ifndef NO_PTHREADS
 
 /*
- * Join thread, with apporiate errors on failure. Name is name for the
+ * Join thread, with appropriate errors on failure. Name is name for the
  * thread (for error messages). Returns 0 on success, 1 on failure.
  */
 static int tloop_join(pthread_t thread, const char *name)
@@ -1109,7 +1284,7 @@ static void udt_kill_transfer(struct unidirectional_transfer *t)
 }
 
 /*
- * Join process, with apporiate errors on failure. Name is name for the
+ * Join process, with appropriate errors on failure. Name is name for the
  * process (for error messages). Returns 0 on success, 1 on failure.
  */
 static int tloop_join(pid_t pid, const char *name)