Squashed 'third_party/git/' content from commit cb71568594

git-subtree-dir: third_party/git
git-subtree-split: cb715685942260375e1eb8153b0768a376e4ece7

1 files changed, 1396 insertions, 0 deletions

diff --git a/transport.c b/transport.c
new file mode 100644
index 000000000000..778c60bf573a
--- /dev/null
+++ b/transport.c
@@ -0,0 +1,1396 @@
+#include "cache.h"
+#include "config.h"
+#include "transport.h"
+#include "run-command.h"
+#include "pkt-line.h"
+#include "fetch-pack.h"
+#include "remote.h"
+#include "connect.h"
+#include "send-pack.h"
+#include "walker.h"
+#include "bundle.h"
+#include "dir.h"
+#include "refs.h"
+#include "refspec.h"
+#include "branch.h"
+#include "url.h"
+#include "submodule.h"
+#include "string-list.h"
+#include "sha1-array.h"
+#include "sigchain.h"
+#include "transport-internal.h"
+#include "protocol.h"
+#include "object-store.h"
+#include "color.h"
+
+static int transport_use_color = -1;
+static char transport_colors[][COLOR_MAXLEN] = {
+	GIT_COLOR_RESET,
+	GIT_COLOR_RED		/* REJECTED */
+};
+
+enum color_transport {
+	TRANSPORT_COLOR_RESET = 0,
+	TRANSPORT_COLOR_REJECTED = 1
+};
+
+static int transport_color_config(void)
+{
+	const char *keys[] = {
+		"color.transport.reset",
+		"color.transport.rejected"
+	}, *key = "color.transport";
+	char *value;
+	int i;
+	static int initialized;
+
+	if (initialized)
+		return 0;
+	initialized = 1;
+
+	if (!git_config_get_string(key, &value))
+		transport_use_color = git_config_colorbool(key, value);
+
+	if (!want_color_stderr(transport_use_color))
+		return 0;
+
+	for (i = 0; i < ARRAY_SIZE(keys); i++)
+		if (!git_config_get_string(keys[i], &value)) {
+			if (!value)
+				return config_error_nonbool(keys[i]);
+			if (color_parse(value, transport_colors[i]) < 0)
+				return -1;
+		}
+
+	return 0;
+}
+
+static const char *transport_get_color(enum color_transport ix)
+{
+	if (want_color_stderr(transport_use_color))
+		return transport_colors[ix];
+	return "";
+}
+
+static void set_upstreams(struct transport *transport, struct ref *refs,
+	int pretend)
+{
+	struct ref *ref;
+	for (ref = refs; ref; ref = ref->next) {
+		const char *localname;
+		const char *tmp;
+		const char *remotename;
+		int flag = 0;
+		/*
+		 * Check suitability for tracking. Must be successful /
+		 * already up-to-date ref create/modify (not delete).
+		 */
+		if (ref->status != REF_STATUS_OK &&
+			ref->status != REF_STATUS_UPTODATE)
+			continue;
+		if (!ref->peer_ref)
+			continue;
+		if (is_null_oid(&ref->new_oid))
+			continue;
+
+		/* Follow symbolic refs (mainly for HEAD). */
+		localname = ref->peer_ref->name;
+		remotename = ref->name;
+		tmp = resolve_ref_unsafe(localname, RESOLVE_REF_READING,
+					 NULL, &flag);
+		if (tmp && flag & REF_ISSYMREF &&
+			starts_with(tmp, "refs/heads/"))
+			localname = tmp;
+
+		/* Both source and destination must be local branches. */
+		if (!localname || !starts_with(localname, "refs/heads/"))
+			continue;
+		if (!remotename || !starts_with(remotename, "refs/heads/"))
+			continue;
+
+		if (!pretend)
+			install_branch_config(BRANCH_CONFIG_VERBOSE,
+				localname + 11, transport->remote->name,
+				remotename);
+		else
+			printf(_("Would set upstream of '%s' to '%s' of '%s'\n"),
+				localname + 11, remotename + 11,
+				transport->remote->name);
+	}
+}
+
+struct bundle_transport_data {
+	int fd;
+	struct bundle_header header;
+};
+
+static struct ref *get_refs_from_bundle(struct transport *transport,
+					int for_push,
+					const struct argv_array *ref_prefixes)
+{
+	struct bundle_transport_data *data = transport->data;
+	struct ref *result = NULL;
+	int i;
+
+	if (for_push)
+		return NULL;
+
+	if (data->fd > 0)
+		close(data->fd);
+	data->fd = read_bundle_header(transport->url, &data->header);
+	if (data->fd < 0)
+		die(_("could not read bundle '%s'"), transport->url);
+	for (i = 0; i < data->header.references.nr; i++) {
+		struct ref_list_entry *e = data->header.references.list + i;
+		struct ref *ref = alloc_ref(e->name);
+		oidcpy(&ref->old_oid, &e->oid);
+		ref->next = result;
+		result = ref;
+	}
+	return result;
+}
+
+static int fetch_refs_from_bundle(struct transport *transport,
+			       int nr_heads, struct ref **to_fetch)
+{
+	struct bundle_transport_data *data = transport->data;
+	return unbundle(the_repository, &data->header, data->fd,
+			transport->progress ? BUNDLE_VERBOSE : 0);
+}
+
+static int close_bundle(struct transport *transport)
+{
+	struct bundle_transport_data *data = transport->data;
+	if (data->fd > 0)
+		close(data->fd);
+	free(data);
+	return 0;
+}
+
+struct git_transport_data {
+	struct git_transport_options options;
+	struct child_process *conn;
+	int fd[2];
+	unsigned got_remote_heads : 1;
+	enum protocol_version version;
+	struct oid_array extra_have;
+	struct oid_array shallow;
+};
+
+static int set_git_option(struct git_transport_options *opts,
+			  const char *name, const char *value)
+{
+	if (!strcmp(name, TRANS_OPT_UPLOADPACK)) {
+		opts->uploadpack = value;
+		return 0;
+	} else if (!strcmp(name, TRANS_OPT_RECEIVEPACK)) {
+		opts->receivepack = value;
+		return 0;
+	} else if (!strcmp(name, TRANS_OPT_THIN)) {
+		opts->thin = !!value;
+		return 0;
+	} else if (!strcmp(name, TRANS_OPT_FOLLOWTAGS)) {
+		opts->followtags = !!value;
+		return 0;
+	} else if (!strcmp(name, TRANS_OPT_KEEP)) {
+		opts->keep = !!value;
+		return 0;
+	} else if (!strcmp(name, TRANS_OPT_UPDATE_SHALLOW)) {
+		opts->update_shallow = !!value;
+		return 0;
+	} else if (!strcmp(name, TRANS_OPT_DEPTH)) {
+		if (!value)
+			opts->depth = 0;
+		else {
+			char *end;
+			opts->depth = strtol(value, &end, 0);
+			if (*end)
+				die(_("transport: invalid depth option '%s'"), value);
+		}
+		return 0;
+	} else if (!strcmp(name, TRANS_OPT_DEEPEN_SINCE)) {
+		opts->deepen_since = value;
+		return 0;
+	} else if (!strcmp(name, TRANS_OPT_DEEPEN_NOT)) {
+		opts->deepen_not = (const struct string_list *)value;
+		return 0;
+	} else if (!strcmp(name, TRANS_OPT_DEEPEN_RELATIVE)) {
+		opts->deepen_relative = !!value;
+		return 0;
+	} else if (!strcmp(name, TRANS_OPT_FROM_PROMISOR)) {
+		opts->from_promisor = !!value;
+		return 0;
+	} else if (!strcmp(name, TRANS_OPT_NO_DEPENDENTS)) {
+		opts->no_dependents = !!value;
+		return 0;
+	} else if (!strcmp(name, TRANS_OPT_LIST_OBJECTS_FILTER)) {
+		parse_list_objects_filter(&opts->filter_options, value);
+		return 0;
+	}
+	return 1;
+}
+
+static int connect_setup(struct transport *transport, int for_push)
+{
+	struct git_transport_data *data = transport->data;
+	int flags = transport->verbose > 0 ? CONNECT_VERBOSE : 0;
+
+	if (data->conn)
+		return 0;
+
+	switch (transport->family) {
+	case TRANSPORT_FAMILY_ALL: break;
+	case TRANSPORT_FAMILY_IPV4: flags |= CONNECT_IPV4; break;
+	case TRANSPORT_FAMILY_IPV6: flags |= CONNECT_IPV6; break;
+	}
+
+	data->conn = git_connect(data->fd, transport->url,
+				 for_push ? data->options.receivepack :
+				 data->options.uploadpack,
+				 flags);
+
+	return 0;
+}
+
+static void die_if_server_options(struct transport *transport)
+{
+	if (!transport->server_options || !transport->server_options->nr)
+		return;
+	advise(_("see protocol.version in 'git help config' for more details"));
+	die(_("server options require protocol version 2 or later"));
+}
+
+/*
+ * Obtains the protocol version from the transport and writes it to
+ * transport->data->version, first connecting if not already connected.
+ *
+ * If the protocol version is one that allows skipping the listing of remote
+ * refs, and must_list_refs is 0, the listing of remote refs is skipped and
+ * this function returns NULL. Otherwise, this function returns the list of
+ * remote refs.
+ */
+static struct ref *handshake(struct transport *transport, int for_push,
+			     const struct argv_array *ref_prefixes,
+			     int must_list_refs)
+{
+	struct git_transport_data *data = transport->data;
+	struct ref *refs = NULL;
+	struct packet_reader reader;
+
+	connect_setup(transport, for_push);
+
+	packet_reader_init(&reader, data->fd[0], NULL, 0,
+			   PACKET_READ_CHOMP_NEWLINE |
+			   PACKET_READ_GENTLE_ON_EOF |
+			   PACKET_READ_DIE_ON_ERR_PACKET);
+
+	data->version = discover_version(&reader);
+	switch (data->version) {
+	case protocol_v2:
+		if (must_list_refs)
+			get_remote_refs(data->fd[1], &reader, &refs, for_push,
+					ref_prefixes,
+					transport->server_options);
+		break;
+	case protocol_v1:
+	case protocol_v0:
+		die_if_server_options(transport);
+		get_remote_heads(&reader, &refs,
+				 for_push ? REF_NORMAL : 0,
+				 &data->extra_have,
+				 &data->shallow);
+		break;
+	case protocol_unknown_version:
+		BUG("unknown protocol version");
+	}
+	data->got_remote_heads = 1;
+
+	if (reader.line_peeked)
+		BUG("buffer must be empty at the end of handshake()");
+
+	return refs;
+}
+
+static struct ref *get_refs_via_connect(struct transport *transport, int for_push,
+					const struct argv_array *ref_prefixes)
+{
+	return handshake(transport, for_push, ref_prefixes, 1);
+}
+
+static int fetch_refs_via_pack(struct transport *transport,
+			       int nr_heads, struct ref **to_fetch)
+{
+	int ret = 0;
+	struct git_transport_data *data = transport->data;
+	struct ref *refs = NULL;
+	struct fetch_pack_args args;
+	struct ref *refs_tmp = NULL;
+
+	memset(&args, 0, sizeof(args));
+	args.uploadpack = data->options.uploadpack;
+	args.keep_pack = data->options.keep;
+	args.lock_pack = 1;
+	args.use_thin_pack = data->options.thin;
+	args.include_tag = data->options.followtags;
+	args.verbose = (transport->verbose > 1);
+	args.quiet = (transport->verbose < 0);
+	args.no_progress = !transport->progress;
+	args.depth = data->options.depth;
+	args.deepen_since = data->options.deepen_since;
+	args.deepen_not = data->options.deepen_not;
+	args.deepen_relative = data->options.deepen_relative;
+	args.check_self_contained_and_connected =
+		data->options.check_self_contained_and_connected;
+	args.cloning = transport->cloning;
+	args.update_shallow = data->options.update_shallow;
+	args.from_promisor = data->options.from_promisor;
+	args.no_dependents = data->options.no_dependents;
+	args.filter_options = data->options.filter_options;
+	args.stateless_rpc = transport->stateless_rpc;
+	args.server_options = transport->server_options;
+	args.negotiation_tips = data->options.negotiation_tips;
+
+	if (!data->got_remote_heads) {
+		int i;
+		int must_list_refs = 0;
+		for (i = 0; i < nr_heads; i++) {
+			if (!to_fetch[i]->exact_oid) {
+				must_list_refs = 1;
+				break;
+			}
+		}
+		refs_tmp = handshake(transport, 0, NULL, must_list_refs);
+	}
+
+	switch (data->version) {
+	case protocol_v2:
+		refs = fetch_pack(&args, data->fd,
+				  refs_tmp ? refs_tmp : transport->remote_refs,
+				  to_fetch, nr_heads, &data->shallow,
+				  &transport->pack_lockfile, data->version);
+		break;
+	case protocol_v1:
+	case protocol_v0:
+		die_if_server_options(transport);
+		refs = fetch_pack(&args, data->fd,
+				  refs_tmp ? refs_tmp : transport->remote_refs,
+				  to_fetch, nr_heads, &data->shallow,
+				  &transport->pack_lockfile, data->version);
+		break;
+	case protocol_unknown_version:
+		BUG("unknown protocol version");
+	}
+
+	close(data->fd[0]);
+	close(data->fd[1]);
+	if (finish_connect(data->conn))
+		ret = -1;
+	data->conn = NULL;
+	data->got_remote_heads = 0;
+	data->options.self_contained_and_connected =
+		args.self_contained_and_connected;
+	data->options.connectivity_checked = args.connectivity_checked;
+
+	if (refs == NULL)
+		ret = -1;
+	if (report_unmatched_refs(to_fetch, nr_heads))
+		ret = -1;
+
+	free_refs(refs_tmp);
+	free_refs(refs);
+	return ret;
+}
+
+static int push_had_errors(struct ref *ref)
+{
+	for (; ref; ref = ref->next) {
+		switch (ref->status) {
+		case REF_STATUS_NONE:
+		case REF_STATUS_UPTODATE:
+		case REF_STATUS_OK:
+			break;
+		default:
+			return 1;
+		}
+	}
+	return 0;
+}
+
+int transport_refs_pushed(struct ref *ref)
+{
+	for (; ref; ref = ref->next) {
+		switch(ref->status) {
+		case REF_STATUS_NONE:
+		case REF_STATUS_UPTODATE:
+			break;
+		default:
+			return 1;
+		}
+	}
+	return 0;
+}
+
+void transport_update_tracking_ref(struct remote *remote, struct ref *ref, int verbose)
+{
+	struct refspec_item rs;
+
+	if (ref->status != REF_STATUS_OK && ref->status != REF_STATUS_UPTODATE)
+		return;
+
+	rs.src = ref->name;
+	rs.dst = NULL;
+
+	if (!remote_find_tracking(remote, &rs)) {
+		if (verbose)
+			fprintf(stderr, "updating local tracking ref '%s'\n", rs.dst);
+		if (ref->deletion) {
+			delete_ref(NULL, rs.dst, NULL, 0);
+		} else
+			update_ref("update by push", rs.dst, &ref->new_oid,
+				   NULL, 0, 0);
+		free(rs.dst);
+	}
+}
+
+static void print_ref_status(char flag, const char *summary,
+			     struct ref *to, struct ref *from, const char *msg,
+			     int porcelain, int summary_width)
+{
+	if (porcelain) {
+		if (from)
+			fprintf(stdout, "%c\t%s:%s\t", flag, from->name, to->name);
+		else
+			fprintf(stdout, "%c\t:%s\t", flag, to->name);
+		if (msg)
+			fprintf(stdout, "%s (%s)\n", summary, msg);
+		else
+			fprintf(stdout, "%s\n", summary);
+	} else {
+		const char *red = "", *reset = "";
+		if (push_had_errors(to)) {
+			red = transport_get_color(TRANSPORT_COLOR_REJECTED);
+			reset = transport_get_color(TRANSPORT_COLOR_RESET);
+		}
+		fprintf(stderr, " %s%c %-*s%s ", red, flag, summary_width,
+			summary, reset);
+		if (from)
+			fprintf(stderr, "%s -> %s", prettify_refname(from->name), prettify_refname(to->name));
+		else
+			fputs(prettify_refname(to->name), stderr);
+		if (msg) {
+			fputs(" (", stderr);
+			fputs(msg, stderr);
+			fputc(')', stderr);
+		}
+		fputc('\n', stderr);
+	}
+}
+
+static void print_ok_ref_status(struct ref *ref, int porcelain, int summary_width)
+{
+	if (ref->deletion)
+		print_ref_status('-', "[deleted]", ref, NULL, NULL,
+				 porcelain, summary_width);
+	else if (is_null_oid(&ref->old_oid))
+		print_ref_status('*',
+			(starts_with(ref->name, "refs/tags/") ? "[new tag]" :
+			"[new branch]"),
+			ref, ref->peer_ref, NULL, porcelain, summary_width);
+	else {
+		struct strbuf quickref = STRBUF_INIT;
+		char type;
+		const char *msg;
+
+		strbuf_add_unique_abbrev(&quickref, &ref->old_oid,
+					 DEFAULT_ABBREV);
+		if (ref->forced_update) {
+			strbuf_addstr(&quickref, "...");
+			type = '+';
+			msg = "forced update";
+		} else {
+			strbuf_addstr(&quickref, "..");
+			type = ' ';
+			msg = NULL;
+		}
+		strbuf_add_unique_abbrev(&quickref, &ref->new_oid,
+					 DEFAULT_ABBREV);
+
+		print_ref_status(type, quickref.buf, ref, ref->peer_ref, msg,
+				 porcelain, summary_width);
+		strbuf_release(&quickref);
+	}
+}
+
+static int print_one_push_status(struct ref *ref, const char *dest, int count,
+				 int porcelain, int summary_width)
+{
+	if (!count) {
+		char *url = transport_anonymize_url(dest);
+		fprintf(porcelain ? stdout : stderr, "To %s\n", url);
+		free(url);
+	}
+
+	switch(ref->status) {
+	case REF_STATUS_NONE:
+		print_ref_status('X', "[no match]", ref, NULL, NULL,
+				 porcelain, summary_width);
+		break;
+	case REF_STATUS_REJECT_NODELETE:
+		print_ref_status('!', "[rejected]", ref, NULL,
+				 "remote does not support deleting refs",
+				 porcelain, summary_width);
+		break;
+	case REF_STATUS_UPTODATE:
+		print_ref_status('=', "[up to date]", ref,
+				 ref->peer_ref, NULL, porcelain, summary_width);
+		break;
+	case REF_STATUS_REJECT_NONFASTFORWARD:
+		print_ref_status('!', "[rejected]", ref, ref->peer_ref,
+				 "non-fast-forward", porcelain, summary_width);
+		break;
+	case REF_STATUS_REJECT_ALREADY_EXISTS:
+		print_ref_status('!', "[rejected]", ref, ref->peer_ref,
+				 "already exists", porcelain, summary_width);
+		break;
+	case REF_STATUS_REJECT_FETCH_FIRST:
+		print_ref_status('!', "[rejected]", ref, ref->peer_ref,
+				 "fetch first", porcelain, summary_width);
+		break;
+	case REF_STATUS_REJECT_NEEDS_FORCE:
+		print_ref_status('!', "[rejected]", ref, ref->peer_ref,
+				 "needs force", porcelain, summary_width);
+		break;
+	case REF_STATUS_REJECT_STALE:
+		print_ref_status('!', "[rejected]", ref, ref->peer_ref,
+				 "stale info", porcelain, summary_width);
+		break;
+	case REF_STATUS_REJECT_SHALLOW:
+		print_ref_status('!', "[rejected]", ref, ref->peer_ref,
+				 "new shallow roots not allowed",
+				 porcelain, summary_width);
+		break;
+	case REF_STATUS_REMOTE_REJECT:
+		print_ref_status('!', "[remote rejected]", ref,
+				 ref->deletion ? NULL : ref->peer_ref,
+				 ref->remote_status, porcelain, summary_width);
+		break;
+	case REF_STATUS_EXPECTING_REPORT:
+		print_ref_status('!', "[remote failure]", ref,
+				 ref->deletion ? NULL : ref->peer_ref,
+				 "remote failed to report status",
+				 porcelain, summary_width);
+		break;
+	case REF_STATUS_ATOMIC_PUSH_FAILED:
+		print_ref_status('!', "[rejected]", ref, ref->peer_ref,
+				 "atomic push failed", porcelain, summary_width);
+		break;
+	case REF_STATUS_OK:
+		print_ok_ref_status(ref, porcelain, summary_width);
+		break;
+	}
+
+	return 1;
+}
+
+static int measure_abbrev(const struct object_id *oid, int sofar)
+{
+	char hex[GIT_MAX_HEXSZ + 1];
+	int w = find_unique_abbrev_r(hex, oid, DEFAULT_ABBREV);
+
+	return (w < sofar) ? sofar : w;
+}
+
+int transport_summary_width(const struct ref *refs)
+{
+	int maxw = -1;
+
+	for (; refs; refs = refs->next) {
+		maxw = measure_abbrev(&refs->old_oid, maxw);
+		maxw = measure_abbrev(&refs->new_oid, maxw);
+	}
+	if (maxw < 0)
+		maxw = FALLBACK_DEFAULT_ABBREV;
+	return (2 * maxw + 3);
+}
+
+void transport_print_push_status(const char *dest, struct ref *refs,
+				  int verbose, int porcelain, unsigned int *reject_reasons)
+{
+	struct ref *ref;
+	int n = 0;
+	char *head;
+	int summary_width = transport_summary_width(refs);
+
+	if (transport_color_config() < 0)
+		warning(_("could not parse transport.color.* config"));
+
+	head = resolve_refdup("HEAD", RESOLVE_REF_READING, NULL, NULL);
+
+	if (verbose) {
+		for (ref = refs; ref; ref = ref->next)
+			if (ref->status == REF_STATUS_UPTODATE)
+				n += print_one_push_status(ref, dest, n,
+							   porcelain, summary_width);
+	}
+
+	for (ref = refs; ref; ref = ref->next)
+		if (ref->status == REF_STATUS_OK)
+			n += print_one_push_status(ref, dest, n,
+						   porcelain, summary_width);
+
+	*reject_reasons = 0;
+	for (ref = refs; ref; ref = ref->next) {
+		if (ref->status != REF_STATUS_NONE &&
+		    ref->status != REF_STATUS_UPTODATE &&
+		    ref->status != REF_STATUS_OK)
+			n += print_one_push_status(ref, dest, n,
+						   porcelain, summary_width);
+		if (ref->status == REF_STATUS_REJECT_NONFASTFORWARD) {
+			if (head != NULL && !strcmp(head, ref->name))
+				*reject_reasons |= REJECT_NON_FF_HEAD;
+			else
+				*reject_reasons |= REJECT_NON_FF_OTHER;
+		} else if (ref->status == REF_STATUS_REJECT_ALREADY_EXISTS) {
+			*reject_reasons |= REJECT_ALREADY_EXISTS;
+		} else if (ref->status == REF_STATUS_REJECT_FETCH_FIRST) {
+			*reject_reasons |= REJECT_FETCH_FIRST;
+		} else if (ref->status == REF_STATUS_REJECT_NEEDS_FORCE) {
+			*reject_reasons |= REJECT_NEEDS_FORCE;
+		}
+	}
+	free(head);
+}
+
+static int git_transport_push(struct transport *transport, struct ref *remote_refs, int flags)
+{
+	struct git_transport_data *data = transport->data;
+	struct send_pack_args args;
+	int ret = 0;
+
+	if (transport_color_config() < 0)
+		return -1;
+
+	if (!data->got_remote_heads)
+		get_refs_via_connect(transport, 1, NULL);
+
+	memset(&args, 0, sizeof(args));
+	args.send_mirror = !!(flags & TRANSPORT_PUSH_MIRROR);
+	args.force_update = !!(flags & TRANSPORT_PUSH_FORCE);
+	args.use_thin_pack = data->options.thin;
+	args.verbose = (transport->verbose > 0);
+	args.quiet = (transport->verbose < 0);
+	args.progress = transport->progress;
+	args.dry_run = !!(flags & TRANSPORT_PUSH_DRY_RUN);
+	args.porcelain = !!(flags & TRANSPORT_PUSH_PORCELAIN);
+	args.atomic = !!(flags & TRANSPORT_PUSH_ATOMIC);
+	args.push_options = transport->push_options;
+	args.url = transport->url;
+
+	if (flags & TRANSPORT_PUSH_CERT_ALWAYS)
+		args.push_cert = SEND_PACK_PUSH_CERT_ALWAYS;
+	else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED)
+		args.push_cert = SEND_PACK_PUSH_CERT_IF_ASKED;
+	else
+		args.push_cert = SEND_PACK_PUSH_CERT_NEVER;
+
+	switch (data->version) {
+	case protocol_v2:
+		die(_("support for protocol v2 not implemented yet"));
+		break;
+	case protocol_v1:
+	case protocol_v0:
+		ret = send_pack(&args, data->fd, data->conn, remote_refs,
+				&data->extra_have);
+		break;
+	case protocol_unknown_version:
+		BUG("unknown protocol version");
+	}
+
+	close(data->fd[1]);
+	close(data->fd[0]);
+	ret |= finish_connect(data->conn);
+	data->conn = NULL;
+	data->got_remote_heads = 0;
+
+	return ret;
+}
+
+static int connect_git(struct transport *transport, const char *name,
+		       const char *executable, int fd[2])
+{
+	struct git_transport_data *data = transport->data;
+	data->conn = git_connect(data->fd, transport->url,
+				 executable, 0);
+	fd[0] = data->fd[0];
+	fd[1] = data->fd[1];
+	return 0;
+}
+
+static int disconnect_git(struct transport *transport)
+{
+	struct git_transport_data *data = transport->data;
+	if (data->conn) {
+		if (data->got_remote_heads)
+			packet_flush(data->fd[1]);
+		close(data->fd[0]);
+		close(data->fd[1]);
+		finish_connect(data->conn);
+	}
+
+	free(data);
+	return 0;
+}
+
+static struct transport_vtable taken_over_vtable = {
+	1,
+	NULL,
+	get_refs_via_connect,
+	fetch_refs_via_pack,
+	git_transport_push,
+	NULL,
+	disconnect_git
+};
+
+void transport_take_over(struct transport *transport,
+			 struct child_process *child)
+{
+	struct git_transport_data *data;
+
+	if (!transport->smart_options)
+		BUG("taking over transport requires non-NULL "
+		    "smart_options field.");
+
+	data = xcalloc(1, sizeof(*data));
+	data->options = *transport->smart_options;
+	data->conn = child;
+	data->fd[0] = data->conn->out;
+	data->fd[1] = data->conn->in;
+	data->got_remote_heads = 0;
+	transport->data = data;
+
+	transport->vtable = &taken_over_vtable;
+	transport->smart_options = &(data->options);
+
+	transport->cannot_reuse = 1;
+}
+
+static int is_file(const char *url)
+{
+	struct stat buf;
+	if (stat(url, &buf))
+		return 0;
+	return S_ISREG(buf.st_mode);
+}
+
+static int external_specification_len(const char *url)
+{
+	return strchr(url, ':') - url;
+}
+
+static const struct string_list *protocol_whitelist(void)
+{
+	static int enabled = -1;
+	static struct string_list allowed = STRING_LIST_INIT_DUP;
+
+	if (enabled < 0) {
+		const char *v = getenv("GIT_ALLOW_PROTOCOL");
+		if (v) {
+			string_list_split(&allowed, v, ':', -1);
+			string_list_sort(&allowed);
+			enabled = 1;
+		} else {
+			enabled = 0;
+		}
+	}
+
+	return enabled ? &allowed : NULL;
+}
+
+enum protocol_allow_config {
+	PROTOCOL_ALLOW_NEVER = 0,
+	PROTOCOL_ALLOW_USER_ONLY,
+	PROTOCOL_ALLOW_ALWAYS
+};
+
+static enum protocol_allow_config parse_protocol_config(const char *key,
+							const char *value)
+{
+	if (!strcasecmp(value, "always"))
+		return PROTOCOL_ALLOW_ALWAYS;
+	else if (!strcasecmp(value, "never"))
+		return PROTOCOL_ALLOW_NEVER;
+	else if (!strcasecmp(value, "user"))
+		return PROTOCOL_ALLOW_USER_ONLY;
+
+	die(_("unknown value for config '%s': %s"), key, value);
+}
+
+static enum protocol_allow_config get_protocol_config(const char *type)
+{
+	char *key = xstrfmt("protocol.%s.allow", type);
+	char *value;
+
+	/* first check the per-protocol config */
+	if (!git_config_get_string(key, &value)) {
+		enum protocol_allow_config ret =
+			parse_protocol_config(key, value);
+		free(key);
+		free(value);
+		return ret;
+	}
+	free(key);
+
+	/* if defined, fallback to user-defined default for unknown protocols */
+	if (!git_config_get_string("protocol.allow", &value)) {
+		enum protocol_allow_config ret =
+			parse_protocol_config("protocol.allow", value);
+		free(value);
+		return ret;
+	}
+
+	/* fallback to built-in defaults */
+	/* known safe */
+	if (!strcmp(type, "http") ||
+	    !strcmp(type, "https") ||
+	    !strcmp(type, "git") ||
+	    !strcmp(type, "ssh") ||
+	    !strcmp(type, "file"))
+		return PROTOCOL_ALLOW_ALWAYS;
+
+	/* known scary; err on the side of caution */
+	if (!strcmp(type, "ext"))
+		return PROTOCOL_ALLOW_NEVER;
+
+	/* unknown; by default let them be used only directly by the user */
+	return PROTOCOL_ALLOW_USER_ONLY;
+}
+
+int is_transport_allowed(const char *type, int from_user)
+{
+	const struct string_list *whitelist = protocol_whitelist();
+	if (whitelist)
+		return string_list_has_string(whitelist, type);
+
+	switch (get_protocol_config(type)) {
+	case PROTOCOL_ALLOW_ALWAYS:
+		return 1;
+	case PROTOCOL_ALLOW_NEVER:
+		return 0;
+	case PROTOCOL_ALLOW_USER_ONLY:
+		if (from_user < 0)
+			from_user = git_env_bool("GIT_PROTOCOL_FROM_USER", 1);
+		return from_user;
+	}
+
+	BUG("invalid protocol_allow_config type");
+}
+
+void transport_check_allowed(const char *type)
+{
+	if (!is_transport_allowed(type, -1))
+		die(_("transport '%s' not allowed"), type);
+}
+
+static struct transport_vtable bundle_vtable = {
+	0,
+	NULL,
+	get_refs_from_bundle,
+	fetch_refs_from_bundle,
+	NULL,
+	NULL,
+	close_bundle
+};
+
+static struct transport_vtable builtin_smart_vtable = {
+	1,
+	NULL,
+	get_refs_via_connect,
+	fetch_refs_via_pack,
+	git_transport_push,
+	connect_git,
+	disconnect_git
+};
+
+struct transport *transport_get(struct remote *remote, const char *url)
+{
+	const char *helper;
+	struct transport *ret = xcalloc(1, sizeof(*ret));
+
+	ret->progress = isatty(2);
+
+	if (!remote)
+		BUG("No remote provided to transport_get()");
+
+	ret->got_remote_refs = 0;
+	ret->remote = remote;
+	helper = remote->foreign_vcs;
+
+	if (!url && remote->url)
+		url = remote->url[0];
+	ret->url = url;
+
+	/* maybe it is a foreign URL? */
+	if (url) {
+		const char *p = url;
+
+		while (is_urlschemechar(p == url, *p))
+			p++;
+		if (starts_with(p, "::"))
+			helper = xstrndup(url, p - url);
+	}
+
+	if (helper) {
+		transport_helper_init(ret, helper);
+	} else if (starts_with(url, "rsync:")) {
+		die(_("git-over-rsync is no longer supported"));
+	} else if (url_is_local_not_ssh(url) && is_file(url) && is_bundle(url, 1)) {
+		struct bundle_transport_data *data = xcalloc(1, sizeof(*data));
+		transport_check_allowed("file");
+		ret->data = data;
+		ret->vtable = &bundle_vtable;
+		ret->smart_options = NULL;
+	} else if (!is_url(url)
+		|| starts_with(url, "file://")
+		|| starts_with(url, "git://")
+		|| starts_with(url, "ssh://")
+		|| starts_with(url, "git+ssh://") /* deprecated - do not use */
+		|| starts_with(url, "ssh+git://") /* deprecated - do not use */
+		) {
+		/*
+		 * These are builtin smart transports; "allowed" transports
+		 * will be checked individually in git_connect.
+		 */
+		struct git_transport_data *data = xcalloc(1, sizeof(*data));
+		ret->data = data;
+		ret->vtable = &builtin_smart_vtable;
+		ret->smart_options = &(data->options);
+
+		data->conn = NULL;
+		data->got_remote_heads = 0;
+	} else {
+		/* Unknown protocol in URL. Pass to external handler. */
+		int len = external_specification_len(url);
+		char *handler = xmemdupz(url, len);
+		transport_helper_init(ret, handler);
+	}
+
+	if (ret->smart_options) {
+		ret->smart_options->thin = 1;
+		ret->smart_options->uploadpack = "git-upload-pack";
+		if (remote->uploadpack)
+			ret->smart_options->uploadpack = remote->uploadpack;
+		ret->smart_options->receivepack = "git-receive-pack";
+		if (remote->receivepack)
+			ret->smart_options->receivepack = remote->receivepack;
+	}
+
+	return ret;
+}
+
+int transport_set_option(struct transport *transport,
+			 const char *name, const char *value)
+{
+	int git_reports = 1, protocol_reports = 1;
+
+	if (transport->smart_options)
+		git_reports = set_git_option(transport->smart_options,
+					     name, value);
+
+	if (transport->vtable->set_option)
+		protocol_reports = transport->vtable->set_option(transport,
+								 name, value);
+
+	/* If either report is 0, report 0 (success). */
+	if (!git_reports || !protocol_reports)
+		return 0;
+	/* If either reports -1 (invalid value), report -1. */
+	if ((git_reports == -1) || (protocol_reports == -1))
+		return -1;
+	/* Otherwise if both report unknown, report unknown. */
+	return 1;
+}
+
+void transport_set_verbosity(struct transport *transport, int verbosity,
+	int force_progress)
+{
+	if (verbosity >= 1)
+		transport->verbose = verbosity <= 3 ? verbosity : 3;
+	if (verbosity < 0)
+		transport->verbose = -1;
+
+	/**
+	 * Rules used to determine whether to report progress (processing aborts
+	 * when a rule is satisfied):
+	 *
+	 *   . Report progress, if force_progress is 1 (ie. --progress).
+	 *   . Don't report progress, if force_progress is 0 (ie. --no-progress).
+	 *   . Don't report progress, if verbosity < 0 (ie. -q/--quiet ).
+	 *   . Report progress if isatty(2) is 1.
+	 **/
+	if (force_progress >= 0)
+		transport->progress = !!force_progress;
+	else
+		transport->progress = verbosity >= 0 && isatty(2);
+}
+
+static void die_with_unpushed_submodules(struct string_list *needs_pushing)
+{
+	int i;
+
+	fprintf(stderr, _("The following submodule paths contain changes that can\n"
+			"not be found on any remote:\n"));
+	for (i = 0; i < needs_pushing->nr; i++)
+		fprintf(stderr, "  %s\n", needs_pushing->items[i].string);
+	fprintf(stderr, _("\nPlease try\n\n"
+			  "	git push --recurse-submodules=on-demand\n\n"
+			  "or cd to the path and use\n\n"
+			  "	git push\n\n"
+			  "to push them to a remote.\n\n"));
+
+	string_list_clear(needs_pushing, 0);
+
+	die(_("Aborting."));
+}
+
+static int run_pre_push_hook(struct transport *transport,
+			     struct ref *remote_refs)
+{
+	int ret = 0, x;
+	struct ref *r;
+	struct child_process proc = CHILD_PROCESS_INIT;
+	struct strbuf buf;
+	const char *argv[4];
+
+	if (!(argv[0] = find_hook("pre-push")))
+		return 0;
+
+	argv[1] = transport->remote->name;
+	argv[2] = transport->url;
+	argv[3] = NULL;
+
+	proc.argv = argv;
+	proc.in = -1;
+	proc.trace2_hook_name = "pre-push";
+
+	if (start_command(&proc)) {
+		finish_command(&proc);
+		return -1;
+	}
+
+	sigchain_push(SIGPIPE, SIG_IGN);
+
+	strbuf_init(&buf, 256);
+
+	for (r = remote_refs; r; r = r->next) {
+		if (!r->peer_ref) continue;
+		if (r->status == REF_STATUS_REJECT_NONFASTFORWARD) continue;
+		if (r->status == REF_STATUS_REJECT_STALE) continue;
+		if (r->status == REF_STATUS_UPTODATE) continue;
+
+		strbuf_reset(&buf);
+		strbuf_addf( &buf, "%s %s %s %s\n",
+			 r->peer_ref->name, oid_to_hex(&r->new_oid),
+			 r->name, oid_to_hex(&r->old_oid));
+
+		if (write_in_full(proc.in, buf.buf, buf.len) < 0) {
+			/* We do not mind if a hook does not read all refs. */
+			if (errno != EPIPE)
+				ret = -1;
+			break;
+		}
+	}
+
+	strbuf_release(&buf);
+
+	x = close(proc.in);
+	if (!ret)
+		ret = x;
+
+	sigchain_pop(SIGPIPE);
+
+	x = finish_command(&proc);
+	if (!ret)
+		ret = x;
+
+	return ret;
+}
+
+int transport_push(struct repository *r,
+		   struct transport *transport,
+		   struct refspec *rs, int flags,
+		   unsigned int *reject_reasons)
+{
+	*reject_reasons = 0;
+
+	if (transport_color_config() < 0)
+		return -1;
+
+	if (transport->vtable->push_refs) {
+		struct ref *remote_refs;
+		struct ref *local_refs = get_local_heads();
+		int match_flags = MATCH_REFS_NONE;
+		int verbose = (transport->verbose > 0);
+		int quiet = (transport->verbose < 0);
+		int porcelain = flags & TRANSPORT_PUSH_PORCELAIN;
+		int pretend = flags & TRANSPORT_PUSH_DRY_RUN;
+		int push_ret, ret, err;
+		struct argv_array ref_prefixes = ARGV_ARRAY_INIT;
+
+		if (check_push_refs(local_refs, rs) < 0)
+			return -1;
+
+		refspec_ref_prefixes(rs, &ref_prefixes);
+
+		remote_refs = transport->vtable->get_refs_list(transport, 1,
+							       &ref_prefixes);
+
+		argv_array_clear(&ref_prefixes);
+
+		if (flags & TRANSPORT_PUSH_ALL)
+			match_flags |= MATCH_REFS_ALL;
+		if (flags & TRANSPORT_PUSH_MIRROR)
+			match_flags |= MATCH_REFS_MIRROR;
+		if (flags & TRANSPORT_PUSH_PRUNE)
+			match_flags |= MATCH_REFS_PRUNE;
+		if (flags & TRANSPORT_PUSH_FOLLOW_TAGS)
+			match_flags |= MATCH_REFS_FOLLOW_TAGS;
+
+		if (match_push_refs(local_refs, &remote_refs, rs, match_flags))
+			return -1;
+
+		if (transport->smart_options &&
+		    transport->smart_options->cas &&
+		    !is_empty_cas(transport->smart_options->cas))
+			apply_push_cas(transport->smart_options->cas,
+				       transport->remote, remote_refs);
+
+		set_ref_status_for_push(remote_refs,
+			flags & TRANSPORT_PUSH_MIRROR,
+			flags & TRANSPORT_PUSH_FORCE);
+
+		if (!(flags & TRANSPORT_PUSH_NO_HOOK))
+			if (run_pre_push_hook(transport, remote_refs))
+				return -1;
+
+		if ((flags & (TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND |
+			      TRANSPORT_RECURSE_SUBMODULES_ONLY)) &&
+		    !is_bare_repository()) {
+			struct ref *ref = remote_refs;
+			struct oid_array commits = OID_ARRAY_INIT;
+
+			for (; ref; ref = ref->next)
+				if (!is_null_oid(&ref->new_oid))
+					oid_array_append(&commits,
+							  &ref->new_oid);
+
+			if (!push_unpushed_submodules(r,
+						      &commits,
+						      transport->remote,
+						      rs,
+						      transport->push_options,
+						      pretend)) {
+				oid_array_clear(&commits);
+				die(_("failed to push all needed submodules"));
+			}
+			oid_array_clear(&commits);
+		}
+
+		if (((flags & TRANSPORT_RECURSE_SUBMODULES_CHECK) ||
+		     ((flags & (TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND |
+				TRANSPORT_RECURSE_SUBMODULES_ONLY)) &&
+		      !pretend)) && !is_bare_repository()) {
+			struct ref *ref = remote_refs;
+			struct string_list needs_pushing = STRING_LIST_INIT_DUP;
+			struct oid_array commits = OID_ARRAY_INIT;
+
+			for (; ref; ref = ref->next)
+				if (!is_null_oid(&ref->new_oid))
+					oid_array_append(&commits,
+							  &ref->new_oid);
+
+			if (find_unpushed_submodules(r,
+						     &commits,
+						     transport->remote->name,
+						     &needs_pushing)) {
+				oid_array_clear(&commits);
+				die_with_unpushed_submodules(&needs_pushing);
+			}
+			string_list_clear(&needs_pushing, 0);
+			oid_array_clear(&commits);
+		}
+
+		if (!(flags & TRANSPORT_RECURSE_SUBMODULES_ONLY))
+			push_ret = transport->vtable->push_refs(transport, remote_refs, flags);
+		else
+			push_ret = 0;
+		err = push_had_errors(remote_refs);
+		ret = push_ret | err;
+
+		if ((flags & TRANSPORT_PUSH_ATOMIC) && err) {
+			struct ref *it;
+			for (it = remote_refs; it; it = it->next)
+				switch (it->status) {
+				case REF_STATUS_NONE:
+				case REF_STATUS_UPTODATE:
+				case REF_STATUS_OK:
+					it->status = REF_STATUS_ATOMIC_PUSH_FAILED;
+					break;
+				default:
+					break;
+				}
+		}
+
+		if (!quiet || err)
+			transport_print_push_status(transport->url, remote_refs,
+					verbose | porcelain, porcelain,
+					reject_reasons);
+
+		if (flags & TRANSPORT_PUSH_SET_UPSTREAM)
+			set_upstreams(transport, remote_refs, pretend);
+
+		if (!(flags & (TRANSPORT_PUSH_DRY_RUN |
+			       TRANSPORT_RECURSE_SUBMODULES_ONLY))) {
+			struct ref *ref;
+			for (ref = remote_refs; ref; ref = ref->next)
+				transport_update_tracking_ref(transport->remote, ref, verbose);
+		}
+
+		if (porcelain && !push_ret)
+			puts("Done");
+		else if (!quiet && !ret && !transport_refs_pushed(remote_refs))
+			fprintf(stderr, "Everything up-to-date\n");
+
+		return ret;
+	}
+	return 1;
+}
+
+const struct ref *transport_get_remote_refs(struct transport *transport,
+					    const struct argv_array *ref_prefixes)
+{
+	if (!transport->got_remote_refs) {
+		transport->remote_refs =
+			transport->vtable->get_refs_list(transport, 0,
+							 ref_prefixes);
+		transport->got_remote_refs = 1;
+	}
+
+	return transport->remote_refs;
+}
+
+int transport_fetch_refs(struct transport *transport, struct ref *refs)
+{
+	int rc;
+	int nr_heads = 0, nr_alloc = 0, nr_refs = 0;
+	struct ref **heads = NULL;
+	struct ref *rm;
+
+	if (!transport->vtable->fetch_without_list)
+		/*
+		 * Some transports (e.g. the built-in bundle transport and the
+		 * transport helper interface) do not work when fetching is
+		 * done immediately after transport creation. List the remote
+		 * refs anyway (if not already listed) as a workaround.
+		 */
+		transport_get_remote_refs(transport, NULL);
+
+	for (rm = refs; rm; rm = rm->next) {
+		nr_refs++;
+		if (rm->peer_ref &&
+		    !is_null_oid(&rm->old_oid) &&
+		    oideq(&rm->peer_ref->old_oid, &rm->old_oid))
+			continue;
+		ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
+		heads[nr_heads++] = rm;
+	}
+
+	if (!nr_heads) {
+		/*
+		 * When deepening of a shallow repository is requested,
+		 * then local and remote refs are likely to still be equal.
+		 * Just feed them all to the fetch method in that case.
+		 * This condition shouldn't be met in a non-deepening fetch
+		 * (see builtin/fetch.c:quickfetch()).
+		 */
+		ALLOC_ARRAY(heads, nr_refs);
+		for (rm = refs; rm; rm = rm->next)
+			heads[nr_heads++] = rm;
+	}
+
+	rc = transport->vtable->fetch(transport, nr_heads, heads);
+
+	free(heads);
+	return rc;
+}
+
+void transport_unlock_pack(struct transport *transport)
+{
+	if (transport->pack_lockfile) {
+		unlink_or_warn(transport->pack_lockfile);
+		FREE_AND_NULL(transport->pack_lockfile);
+	}
+}
+
+int transport_connect(struct transport *transport, const char *name,
+		      const char *exec, int fd[2])
+{
+	if (transport->vtable->connect)
+		return transport->vtable->connect(transport, name, exec, fd);
+	else
+		die(_("operation not supported by protocol"));
+}
+
+int transport_disconnect(struct transport *transport)
+{
+	int ret = 0;
+	if (transport->vtable->disconnect)
+		ret = transport->vtable->disconnect(transport);
+	free(transport);
+	return ret;
+}
+
+/*
+ * Strip username (and password) from a URL and return
+ * it in a newly allocated string.
+ */
+char *transport_anonymize_url(const char *url)
+{
+	char *scheme_prefix, *anon_part;
+	size_t anon_len, prefix_len = 0;
+
+	anon_part = strchr(url, '@');
+	if (url_is_local_not_ssh(url) || !anon_part)
+		goto literal_copy;
+
+	anon_len = strlen(++anon_part);
+	scheme_prefix = strstr(url, "://");
+	if (!scheme_prefix) {
+		if (!strchr(anon_part, ':'))
+			/* cannot be "me@there:/path/name" */
+			goto literal_copy;
+	} else {
+		const char *cp;
+		/* make sure scheme is reasonable */
+		for (cp = url; cp < scheme_prefix; cp++) {
+			switch (*cp) {
+				/* RFC 1738 2.1 */
+			case '+': case '.': case '-':
+				break; /* ok */
+			default:
+				if (isalnum(*cp))
+					break;
+				/* it isn't */
+				goto literal_copy;
+			}
+		}
+		/* @ past the first slash does not count */
+		cp = strchr(scheme_prefix + 3, '/');
+		if (cp && cp < anon_part)
+			goto literal_copy;
+		prefix_len = scheme_prefix - url + 3;
+	}
+	return xstrfmt("%.*s%.*s", (int)prefix_len, url,
+		       (int)anon_len, anon_part);
+literal_copy:
+	return xstrdup(url);
+}