Squashed 'third_party/git/' content from commit cb71568594

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

1 files changed, 1448 insertions, 0 deletions

diff --git a/remote-curl.c b/remote-curl.c
new file mode 100644
index 000000000000..051f26629d7b
--- /dev/null
+++ b/remote-curl.c
@@ -0,0 +1,1448 @@
+#include "cache.h"
+#include "config.h"
+#include "remote.h"
+#include "connect.h"
+#include "strbuf.h"
+#include "walker.h"
+#include "http.h"
+#include "exec-cmd.h"
+#include "run-command.h"
+#include "pkt-line.h"
+#include "string-list.h"
+#include "sideband.h"
+#include "argv-array.h"
+#include "credential.h"
+#include "sha1-array.h"
+#include "send-pack.h"
+#include "protocol.h"
+#include "quote.h"
+#include "transport.h"
+
+static struct remote *remote;
+/* always ends with a trailing slash */
+static struct strbuf url = STRBUF_INIT;
+
+struct options {
+	int verbosity;
+	unsigned long depth;
+	char *deepen_since;
+	struct string_list deepen_not;
+	struct string_list push_options;
+	char *filter;
+	unsigned progress : 1,
+		check_self_contained_and_connected : 1,
+		cloning : 1,
+		update_shallow : 1,
+		followtags : 1,
+		dry_run : 1,
+		thin : 1,
+		/* One of the SEND_PACK_PUSH_CERT_* constants. */
+		push_cert : 2,
+		deepen_relative : 1,
+		from_promisor : 1,
+		no_dependents : 1;
+};
+static struct options options;
+static struct string_list cas_options = STRING_LIST_INIT_DUP;
+
+static int set_option(const char *name, const char *value)
+{
+	if (!strcmp(name, "verbosity")) {
+		char *end;
+		int v = strtol(value, &end, 10);
+		if (value == end || *end)
+			return -1;
+		options.verbosity = v;
+		return 0;
+	}
+	else if (!strcmp(name, "progress")) {
+		if (!strcmp(value, "true"))
+			options.progress = 1;
+		else if (!strcmp(value, "false"))
+			options.progress = 0;
+		else
+			return -1;
+		return 0;
+	}
+	else if (!strcmp(name, "depth")) {
+		char *end;
+		unsigned long v = strtoul(value, &end, 10);
+		if (value == end || *end)
+			return -1;
+		options.depth = v;
+		return 0;
+	}
+	else if (!strcmp(name, "deepen-since")) {
+		options.deepen_since = xstrdup(value);
+		return 0;
+	}
+	else if (!strcmp(name, "deepen-not")) {
+		string_list_append(&options.deepen_not, value);
+		return 0;
+	}
+	else if (!strcmp(name, "deepen-relative")) {
+		if (!strcmp(value, "true"))
+			options.deepen_relative = 1;
+		else if (!strcmp(value, "false"))
+			options.deepen_relative = 0;
+		else
+			return -1;
+		return 0;
+	}
+	else if (!strcmp(name, "followtags")) {
+		if (!strcmp(value, "true"))
+			options.followtags = 1;
+		else if (!strcmp(value, "false"))
+			options.followtags = 0;
+		else
+			return -1;
+		return 0;
+	}
+	else if (!strcmp(name, "dry-run")) {
+		if (!strcmp(value, "true"))
+			options.dry_run = 1;
+		else if (!strcmp(value, "false"))
+			options.dry_run = 0;
+		else
+			return -1;
+		return 0;
+	}
+	else if (!strcmp(name, "check-connectivity")) {
+		if (!strcmp(value, "true"))
+			options.check_self_contained_and_connected = 1;
+		else if (!strcmp(value, "false"))
+			options.check_self_contained_and_connected = 0;
+		else
+			return -1;
+		return 0;
+	}
+	else if (!strcmp(name, "cas")) {
+		struct strbuf val = STRBUF_INIT;
+		strbuf_addf(&val, "--" CAS_OPT_NAME "=%s", value);
+		string_list_append(&cas_options, val.buf);
+		strbuf_release(&val);
+		return 0;
+	} else if (!strcmp(name, "cloning")) {
+		if (!strcmp(value, "true"))
+			options.cloning = 1;
+		else if (!strcmp(value, "false"))
+			options.cloning = 0;
+		else
+			return -1;
+		return 0;
+	} else if (!strcmp(name, "update-shallow")) {
+		if (!strcmp(value, "true"))
+			options.update_shallow = 1;
+		else if (!strcmp(value, "false"))
+			options.update_shallow = 0;
+		else
+			return -1;
+		return 0;
+	} else if (!strcmp(name, "pushcert")) {
+		if (!strcmp(value, "true"))
+			options.push_cert = SEND_PACK_PUSH_CERT_ALWAYS;
+		else if (!strcmp(value, "false"))
+			options.push_cert = SEND_PACK_PUSH_CERT_NEVER;
+		else if (!strcmp(value, "if-asked"))
+			options.push_cert = SEND_PACK_PUSH_CERT_IF_ASKED;
+		else
+			return -1;
+		return 0;
+	} else if (!strcmp(name, "push-option")) {
+		if (*value != '"')
+			string_list_append(&options.push_options, value);
+		else {
+			struct strbuf unquoted = STRBUF_INIT;
+			if (unquote_c_style(&unquoted, value, NULL) < 0)
+				die(_("invalid quoting in push-option value: '%s'"), value);
+			string_list_append_nodup(&options.push_options,
+						 strbuf_detach(&unquoted, NULL));
+		}
+		return 0;
+
+#if LIBCURL_VERSION_NUM >= 0x070a08
+	} else if (!strcmp(name, "family")) {
+		if (!strcmp(value, "ipv4"))
+			git_curl_ipresolve = CURL_IPRESOLVE_V4;
+		else if (!strcmp(value, "ipv6"))
+			git_curl_ipresolve = CURL_IPRESOLVE_V6;
+		else if (!strcmp(value, "all"))
+			git_curl_ipresolve = CURL_IPRESOLVE_WHATEVER;
+		else
+			return -1;
+		return 0;
+#endif /* LIBCURL_VERSION_NUM >= 0x070a08 */
+	} else if (!strcmp(name, "from-promisor")) {
+		options.from_promisor = 1;
+		return 0;
+	} else if (!strcmp(name, "no-dependents")) {
+		options.no_dependents = 1;
+		return 0;
+	} else if (!strcmp(name, "filter")) {
+		options.filter = xstrdup(value);
+		return 0;
+	} else {
+		return 1 /* unsupported */;
+	}
+}
+
+struct discovery {
+	char *service;
+	char *buf_alloc;
+	char *buf;
+	size_t len;
+	struct ref *refs;
+	struct oid_array shallow;
+	enum protocol_version version;
+	unsigned proto_git : 1;
+};
+static struct discovery *last_discovery;
+
+static struct ref *parse_git_refs(struct discovery *heads, int for_push)
+{
+	struct ref *list = NULL;
+	struct packet_reader reader;
+
+	packet_reader_init(&reader, -1, heads->buf, heads->len,
+			   PACKET_READ_CHOMP_NEWLINE |
+			   PACKET_READ_GENTLE_ON_EOF |
+			   PACKET_READ_DIE_ON_ERR_PACKET);
+
+	heads->version = discover_version(&reader);
+	switch (heads->version) {
+	case protocol_v2:
+		/*
+		 * Do nothing.  This isn't a list of refs but rather a
+		 * capability advertisement.  Client would have run
+		 * 'stateless-connect' so we'll dump this capability listing
+		 * and let them request the refs themselves.
+		 */
+		break;
+	case protocol_v1:
+	case protocol_v0:
+		get_remote_heads(&reader, &list, for_push ? REF_NORMAL : 0,
+				 NULL, &heads->shallow);
+		break;
+	case protocol_unknown_version:
+		BUG("unknown protocol version");
+	}
+
+	return list;
+}
+
+static struct ref *parse_info_refs(struct discovery *heads)
+{
+	char *data, *start, *mid;
+	char *ref_name;
+	int i = 0;
+
+	struct ref *refs = NULL;
+	struct ref *ref = NULL;
+	struct ref *last_ref = NULL;
+
+	data = heads->buf;
+	start = NULL;
+	mid = data;
+	while (i < heads->len) {
+		if (!start) {
+			start = &data[i];
+		}
+		if (data[i] == '\t')
+			mid = &data[i];
+		if (data[i] == '\n') {
+			if (mid - start != the_hash_algo->hexsz)
+				die(_("%sinfo/refs not valid: is this a git repository?"),
+				    transport_anonymize_url(url.buf));
+			data[i] = 0;
+			ref_name = mid + 1;
+			ref = alloc_ref(ref_name);
+			get_oid_hex(start, &ref->old_oid);
+			if (!refs)
+				refs = ref;
+			if (last_ref)
+				last_ref->next = ref;
+			last_ref = ref;
+			start = NULL;
+		}
+		i++;
+	}
+
+	ref = alloc_ref("HEAD");
+	if (!http_fetch_ref(url.buf, ref) &&
+	    !resolve_remote_symref(ref, refs)) {
+		ref->next = refs;
+		refs = ref;
+	} else {
+		free(ref);
+	}
+
+	return refs;
+}
+
+static void free_discovery(struct discovery *d)
+{
+	if (d) {
+		if (d == last_discovery)
+			last_discovery = NULL;
+		free(d->shallow.oid);
+		free(d->buf_alloc);
+		free_refs(d->refs);
+		free(d->service);
+		free(d);
+	}
+}
+
+static int show_http_message(struct strbuf *type, struct strbuf *charset,
+			     struct strbuf *msg)
+{
+	const char *p, *eol;
+
+	/*
+	 * We only show text/plain parts, as other types are likely
+	 * to be ugly to look at on the user's terminal.
+	 */
+	if (strcmp(type->buf, "text/plain"))
+		return -1;
+	if (charset->len)
+		strbuf_reencode(msg, charset->buf, get_log_output_encoding());
+
+	strbuf_trim(msg);
+	if (!msg->len)
+		return -1;
+
+	p = msg->buf;
+	do {
+		eol = strchrnul(p, '\n');
+		fprintf(stderr, "remote: %.*s\n", (int)(eol - p), p);
+		p = eol + 1;
+	} while(*eol);
+	return 0;
+}
+
+static int get_protocol_http_header(enum protocol_version version,
+				    struct strbuf *header)
+{
+	if (version > 0) {
+		strbuf_addf(header, GIT_PROTOCOL_HEADER ": version=%d",
+			    version);
+
+		return 1;
+	}
+
+	return 0;
+}
+
+static void check_smart_http(struct discovery *d, const char *service,
+			     struct strbuf *type)
+{
+	const char *p;
+	struct packet_reader reader;
+
+	/*
+	 * If we don't see x-$service-advertisement, then it's not smart-http.
+	 * But once we do, we commit to it and assume any other protocol
+	 * violations are hard errors.
+	 */
+	if (!skip_prefix(type->buf, "application/x-", &p) ||
+	    !skip_prefix(p, service, &p) ||
+	    strcmp(p, "-advertisement"))
+		return;
+
+	packet_reader_init(&reader, -1, d->buf, d->len,
+			   PACKET_READ_CHOMP_NEWLINE |
+			   PACKET_READ_DIE_ON_ERR_PACKET);
+	if (packet_reader_read(&reader) != PACKET_READ_NORMAL)
+		die(_("invalid server response; expected service, got flush packet"));
+
+	if (skip_prefix(reader.line, "# service=", &p) && !strcmp(p, service)) {
+		/*
+		 * The header can include additional metadata lines, up
+		 * until a packet flush marker.  Ignore these now, but
+		 * in the future we might start to scan them.
+		 */
+		for (;;) {
+			packet_reader_read(&reader);
+			if (reader.pktlen <= 0) {
+				break;
+			}
+		}
+
+		/*
+		 * v0 smart http; callers expect us to soak up the
+		 * service and header packets
+		 */
+		d->buf = reader.src_buffer;
+		d->len = reader.src_len;
+		d->proto_git = 1;
+
+	} else if (!strcmp(reader.line, "version 2")) {
+		/*
+		 * v2 smart http; do not consume version packet, which will
+		 * be handled elsewhere.
+		 */
+		d->proto_git = 1;
+
+	} else {
+		die(_("invalid server response; got '%s'"), reader.line);
+	}
+}
+
+static struct discovery *discover_refs(const char *service, int for_push)
+{
+	struct strbuf type = STRBUF_INIT;
+	struct strbuf charset = STRBUF_INIT;
+	struct strbuf buffer = STRBUF_INIT;
+	struct strbuf refs_url = STRBUF_INIT;
+	struct strbuf effective_url = STRBUF_INIT;
+	struct strbuf protocol_header = STRBUF_INIT;
+	struct string_list extra_headers = STRING_LIST_INIT_DUP;
+	struct discovery *last = last_discovery;
+	int http_ret, maybe_smart = 0;
+	struct http_get_options http_options;
+	enum protocol_version version = get_protocol_version_config();
+
+	if (last && !strcmp(service, last->service))
+		return last;
+	free_discovery(last);
+
+	strbuf_addf(&refs_url, "%sinfo/refs", url.buf);
+	if ((starts_with(url.buf, "http://") || starts_with(url.buf, "https://")) &&
+	     git_env_bool("GIT_SMART_HTTP", 1)) {
+		maybe_smart = 1;
+		if (!strchr(url.buf, '?'))
+			strbuf_addch(&refs_url, '?');
+		else
+			strbuf_addch(&refs_url, '&');
+		strbuf_addf(&refs_url, "service=%s", service);
+	}
+
+	/*
+	 * NEEDSWORK: If we are trying to use protocol v2 and we are planning
+	 * to perform a push, then fallback to v0 since the client doesn't know
+	 * how to push yet using v2.
+	 */
+	if (version == protocol_v2 && !strcmp("git-receive-pack", service))
+		version = protocol_v0;
+
+	/* Add the extra Git-Protocol header */
+	if (get_protocol_http_header(version, &protocol_header))
+		string_list_append(&extra_headers, protocol_header.buf);
+
+	memset(&http_options, 0, sizeof(http_options));
+	http_options.content_type = &type;
+	http_options.charset = &charset;
+	http_options.effective_url = &effective_url;
+	http_options.base_url = &url;
+	http_options.extra_headers = &extra_headers;
+	http_options.initial_request = 1;
+	http_options.no_cache = 1;
+
+	http_ret = http_get_strbuf(refs_url.buf, &buffer, &http_options);
+	switch (http_ret) {
+	case HTTP_OK:
+		break;
+	case HTTP_MISSING_TARGET:
+		show_http_message(&type, &charset, &buffer);
+		die(_("repository '%s' not found"),
+		    transport_anonymize_url(url.buf));
+	case HTTP_NOAUTH:
+		show_http_message(&type, &charset, &buffer);
+		die(_("Authentication failed for '%s'"),
+		    transport_anonymize_url(url.buf));
+	default:
+		show_http_message(&type, &charset, &buffer);
+		die(_("unable to access '%s': %s"),
+		    transport_anonymize_url(url.buf), curl_errorstr);
+	}
+
+	if (options.verbosity && !starts_with(refs_url.buf, url.buf)) {
+		char *u = transport_anonymize_url(url.buf);
+		warning(_("redirecting to %s"), u);
+		free(u);
+	}
+
+	last= xcalloc(1, sizeof(*last_discovery));
+	last->service = xstrdup(service);
+	last->buf_alloc = strbuf_detach(&buffer, &last->len);
+	last->buf = last->buf_alloc;
+
+	if (maybe_smart)
+		check_smart_http(last, service, &type);
+
+	if (last->proto_git)
+		last->refs = parse_git_refs(last, for_push);
+	else
+		last->refs = parse_info_refs(last);
+
+	strbuf_release(&refs_url);
+	strbuf_release(&type);
+	strbuf_release(&charset);
+	strbuf_release(&effective_url);
+	strbuf_release(&buffer);
+	strbuf_release(&protocol_header);
+	string_list_clear(&extra_headers, 0);
+	last_discovery = last;
+	return last;
+}
+
+static struct ref *get_refs(int for_push)
+{
+	struct discovery *heads;
+
+	if (for_push)
+		heads = discover_refs("git-receive-pack", for_push);
+	else
+		heads = discover_refs("git-upload-pack", for_push);
+
+	return heads->refs;
+}
+
+static void output_refs(struct ref *refs)
+{
+	struct ref *posn;
+	for (posn = refs; posn; posn = posn->next) {
+		if (posn->symref)
+			printf("@%s %s\n", posn->symref, posn->name);
+		else
+			printf("%s %s\n", oid_to_hex(&posn->old_oid), posn->name);
+	}
+	printf("\n");
+	fflush(stdout);
+}
+
+struct rpc_state {
+	const char *service_name;
+	char *service_url;
+	char *hdr_content_type;
+	char *hdr_accept;
+	char *protocol_header;
+	char *buf;
+	size_t alloc;
+	size_t len;
+	size_t pos;
+	int in;
+	int out;
+	int any_written;
+	unsigned gzip_request : 1;
+	unsigned initial_buffer : 1;
+
+	/*
+	 * Whenever a pkt-line is read into buf, append the 4 characters
+	 * denoting its length before appending the payload.
+	 */
+	unsigned write_line_lengths : 1;
+
+	/*
+	 * Used by rpc_out; initialize to 0. This is true if a flush has been
+	 * read, but the corresponding line length (if write_line_lengths is
+	 * true) and EOF have not been sent to libcurl. Since each flush marks
+	 * the end of a request, each flush must be completely sent before any
+	 * further reading occurs.
+	 */
+	unsigned flush_read_but_not_sent : 1;
+};
+
+/*
+ * Appends the result of reading from rpc->out to the string represented by
+ * rpc->buf and rpc->len if there is enough space. Returns 1 if there was
+ * enough space, 0 otherwise.
+ *
+ * If rpc->write_line_lengths is true, appends the line length as a 4-byte
+ * hexadecimal string before appending the result described above.
+ *
+ * Writes the total number of bytes appended into appended.
+ */
+static int rpc_read_from_out(struct rpc_state *rpc, int options,
+			     size_t *appended,
+			     enum packet_read_status *status) {
+	size_t left;
+	char *buf;
+	int pktlen_raw;
+
+	if (rpc->write_line_lengths) {
+		left = rpc->alloc - rpc->len - 4;
+		buf = rpc->buf + rpc->len + 4;
+	} else {
+		left = rpc->alloc - rpc->len;
+		buf = rpc->buf + rpc->len;
+	}
+
+	if (left < LARGE_PACKET_MAX)
+		return 0;
+
+	*status = packet_read_with_status(rpc->out, NULL, NULL, buf,
+			left, &pktlen_raw, options);
+	if (*status != PACKET_READ_EOF) {
+		*appended = pktlen_raw + (rpc->write_line_lengths ? 4 : 0);
+		rpc->len += *appended;
+	}
+
+	if (rpc->write_line_lengths) {
+		switch (*status) {
+		case PACKET_READ_EOF:
+			if (!(options & PACKET_READ_GENTLE_ON_EOF))
+				die(_("shouldn't have EOF when not gentle on EOF"));
+			break;
+		case PACKET_READ_NORMAL:
+			set_packet_header(buf - 4, *appended);
+			break;
+		case PACKET_READ_DELIM:
+			memcpy(buf - 4, "0001", 4);
+			break;
+		case PACKET_READ_FLUSH:
+			memcpy(buf - 4, "0000", 4);
+			break;
+		}
+	}
+
+	return 1;
+}
+
+static size_t rpc_out(void *ptr, size_t eltsize,
+		size_t nmemb, void *buffer_)
+{
+	size_t max = eltsize * nmemb;
+	struct rpc_state *rpc = buffer_;
+	size_t avail = rpc->len - rpc->pos;
+	enum packet_read_status status;
+
+	if (!avail) {
+		rpc->initial_buffer = 0;
+		rpc->len = 0;
+		rpc->pos = 0;
+		if (!rpc->flush_read_but_not_sent) {
+			if (!rpc_read_from_out(rpc, 0, &avail, &status))
+				BUG("The entire rpc->buf should be larger than LARGE_PACKET_MAX");
+			if (status == PACKET_READ_FLUSH)
+				rpc->flush_read_but_not_sent = 1;
+		}
+		/*
+		 * If flush_read_but_not_sent is true, we have already read one
+		 * full request but have not fully sent it + EOF, which is why
+		 * we need to refrain from reading.
+		 */
+	}
+	if (rpc->flush_read_but_not_sent) {
+		if (!avail) {
+			/*
+			 * The line length either does not need to be sent at
+			 * all or has already been completely sent. Now we can
+			 * return 0, indicating EOF, meaning that the flush has
+			 * been fully sent.
+			 */
+			rpc->flush_read_but_not_sent = 0;
+			return 0;
+		}
+		/*
+		 * If avail is non-zerp, the line length for the flush still
+		 * hasn't been fully sent. Proceed with sending the line
+		 * length.
+		 */
+	}
+
+	if (max < avail)
+		avail = max;
+	memcpy(ptr, rpc->buf + rpc->pos, avail);
+	rpc->pos += avail;
+	return avail;
+}
+
+#ifndef NO_CURL_IOCTL
+static curlioerr rpc_ioctl(CURL *handle, int cmd, void *clientp)
+{
+	struct rpc_state *rpc = clientp;
+
+	switch (cmd) {
+	case CURLIOCMD_NOP:
+		return CURLIOE_OK;
+
+	case CURLIOCMD_RESTARTREAD:
+		if (rpc->initial_buffer) {
+			rpc->pos = 0;
+			return CURLIOE_OK;
+		}
+		error(_("unable to rewind rpc post data - try increasing http.postBuffer"));
+		return CURLIOE_FAILRESTART;
+
+	default:
+		return CURLIOE_UNKNOWNCMD;
+	}
+}
+#endif
+
+struct rpc_in_data {
+	struct rpc_state *rpc;
+	struct active_request_slot *slot;
+};
+
+/*
+ * A callback for CURLOPT_WRITEFUNCTION. The return value is the bytes consumed
+ * from ptr.
+ */
+static size_t rpc_in(char *ptr, size_t eltsize,
+		size_t nmemb, void *buffer_)
+{
+	size_t size = eltsize * nmemb;
+	struct rpc_in_data *data = buffer_;
+	long response_code;
+
+	if (curl_easy_getinfo(data->slot->curl, CURLINFO_RESPONSE_CODE,
+			      &response_code) != CURLE_OK)
+		return size;
+	if (response_code >= 300)
+		return size;
+	if (size)
+		data->rpc->any_written = 1;
+	write_or_die(data->rpc->in, ptr, size);
+	return size;
+}
+
+static int run_slot(struct active_request_slot *slot,
+		    struct slot_results *results)
+{
+	int err;
+	struct slot_results results_buf;
+
+	if (!results)
+		results = &results_buf;
+
+	err = run_one_slot(slot, results);
+
+	if (err != HTTP_OK && err != HTTP_REAUTH) {
+		struct strbuf msg = STRBUF_INIT;
+		if (results->http_code && results->http_code != 200)
+			strbuf_addf(&msg, "HTTP %ld", results->http_code);
+		if (results->curl_result != CURLE_OK) {
+			if (msg.len)
+				strbuf_addch(&msg, ' ');
+			strbuf_addf(&msg, "curl %d", results->curl_result);
+			if (curl_errorstr[0]) {
+				strbuf_addch(&msg, ' ');
+				strbuf_addstr(&msg, curl_errorstr);
+			}
+		}
+		error(_("RPC failed; %s"), msg.buf);
+		strbuf_release(&msg);
+	}
+
+	return err;
+}
+
+static int probe_rpc(struct rpc_state *rpc, struct slot_results *results)
+{
+	struct active_request_slot *slot;
+	struct curl_slist *headers = http_copy_default_headers();
+	struct strbuf buf = STRBUF_INIT;
+	int err;
+
+	slot = get_active_slot();
+
+	headers = curl_slist_append(headers, rpc->hdr_content_type);
+	headers = curl_slist_append(headers, rpc->hdr_accept);
+
+	curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
+	curl_easy_setopt(slot->curl, CURLOPT_POST, 1);
+	curl_easy_setopt(slot->curl, CURLOPT_URL, rpc->service_url);
+	curl_easy_setopt(slot->curl, CURLOPT_ENCODING, NULL);
+	curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, "0000");
+	curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDSIZE, 4);
+	curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
+	curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
+	curl_easy_setopt(slot->curl, CURLOPT_FILE, &buf);
+
+	err = run_slot(slot, results);
+
+	curl_slist_free_all(headers);
+	strbuf_release(&buf);
+	return err;
+}
+
+static curl_off_t xcurl_off_t(size_t len)
+{
+	uintmax_t size = len;
+	if (size > maximum_signed_value_of_type(curl_off_t))
+		die(_("cannot handle pushes this big"));
+	return (curl_off_t)size;
+}
+
+/*
+ * If flush_received is true, do not attempt to read any more; just use what's
+ * in rpc->buf.
+ */
+static int post_rpc(struct rpc_state *rpc, int flush_received)
+{
+	struct active_request_slot *slot;
+	struct curl_slist *headers = http_copy_default_headers();
+	int use_gzip = rpc->gzip_request;
+	char *gzip_body = NULL;
+	size_t gzip_size = 0;
+	int err, large_request = 0;
+	int needs_100_continue = 0;
+	struct rpc_in_data rpc_in_data;
+
+	/* Try to load the entire request, if we can fit it into the
+	 * allocated buffer space we can use HTTP/1.0 and avoid the
+	 * chunked encoding mess.
+	 */
+	if (!flush_received) {
+		while (1) {
+			size_t n;
+			enum packet_read_status status;
+
+			if (!rpc_read_from_out(rpc, 0, &n, &status)) {
+				large_request = 1;
+				use_gzip = 0;
+				break;
+			}
+			if (status == PACKET_READ_FLUSH)
+				break;
+		}
+	}
+
+	if (large_request) {
+		struct slot_results results;
+
+		do {
+			err = probe_rpc(rpc, &results);
+			if (err == HTTP_REAUTH)
+				credential_fill(&http_auth);
+		} while (err == HTTP_REAUTH);
+		if (err != HTTP_OK)
+			return -1;
+
+		if (results.auth_avail & CURLAUTH_GSSNEGOTIATE)
+			needs_100_continue = 1;
+	}
+
+	headers = curl_slist_append(headers, rpc->hdr_content_type);
+	headers = curl_slist_append(headers, rpc->hdr_accept);
+	headers = curl_slist_append(headers, needs_100_continue ?
+		"Expect: 100-continue" : "Expect:");
+
+	/* Add the extra Git-Protocol header */
+	if (rpc->protocol_header)
+		headers = curl_slist_append(headers, rpc->protocol_header);
+
+retry:
+	slot = get_active_slot();
+
+	curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
+	curl_easy_setopt(slot->curl, CURLOPT_POST, 1);
+	curl_easy_setopt(slot->curl, CURLOPT_URL, rpc->service_url);
+	curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "");
+
+	if (large_request) {
+		/* The request body is large and the size cannot be predicted.
+		 * We must use chunked encoding to send it.
+		 */
+		headers = curl_slist_append(headers, "Transfer-Encoding: chunked");
+		rpc->initial_buffer = 1;
+		curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, rpc_out);
+		curl_easy_setopt(slot->curl, CURLOPT_INFILE, rpc);
+#ifndef NO_CURL_IOCTL
+		curl_easy_setopt(slot->curl, CURLOPT_IOCTLFUNCTION, rpc_ioctl);
+		curl_easy_setopt(slot->curl, CURLOPT_IOCTLDATA, rpc);
+#endif
+		if (options.verbosity > 1) {
+			fprintf(stderr, "POST %s (chunked)\n", rpc->service_name);
+			fflush(stderr);
+		}
+
+	} else if (gzip_body) {
+		/*
+		 * If we are looping to retry authentication, then the previous
+		 * run will have set up the headers and gzip buffer already,
+		 * and we just need to send it.
+		 */
+		curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, gzip_body);
+		curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDSIZE_LARGE, xcurl_off_t(gzip_size));
+
+	} else if (use_gzip && 1024 < rpc->len) {
+		/* The client backend isn't giving us compressed data so
+		 * we can try to deflate it ourselves, this may save on
+		 * the transfer time.
+		 */
+		git_zstream stream;
+		int ret;
+
+		git_deflate_init_gzip(&stream, Z_BEST_COMPRESSION);
+		gzip_size = git_deflate_bound(&stream, rpc->len);
+		gzip_body = xmalloc(gzip_size);
+
+		stream.next_in = (unsigned char *)rpc->buf;
+		stream.avail_in = rpc->len;
+		stream.next_out = (unsigned char *)gzip_body;
+		stream.avail_out = gzip_size;
+
+		ret = git_deflate(&stream, Z_FINISH);
+		if (ret != Z_STREAM_END)
+			die(_("cannot deflate request; zlib deflate error %d"), ret);
+
+		ret = git_deflate_end_gently(&stream);
+		if (ret != Z_OK)
+			die(_("cannot deflate request; zlib end error %d"), ret);
+
+		gzip_size = stream.total_out;
+
+		headers = curl_slist_append(headers, "Content-Encoding: gzip");
+		curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, gzip_body);
+		curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDSIZE_LARGE, xcurl_off_t(gzip_size));
+
+		if (options.verbosity > 1) {
+			fprintf(stderr, "POST %s (gzip %lu to %lu bytes)\n",
+				rpc->service_name,
+				(unsigned long)rpc->len, (unsigned long)gzip_size);
+			fflush(stderr);
+		}
+	} else {
+		/* We know the complete request size in advance, use the
+		 * more normal Content-Length approach.
+		 */
+		curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, rpc->buf);
+		curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDSIZE_LARGE, xcurl_off_t(rpc->len));
+		if (options.verbosity > 1) {
+			fprintf(stderr, "POST %s (%lu bytes)\n",
+				rpc->service_name, (unsigned long)rpc->len);
+			fflush(stderr);
+		}
+	}
+
+	curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
+	curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, rpc_in);
+	rpc_in_data.rpc = rpc;
+	rpc_in_data.slot = slot;
+	curl_easy_setopt(slot->curl, CURLOPT_FILE, &rpc_in_data);
+	curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
+
+
+	rpc->any_written = 0;
+	err = run_slot(slot, NULL);
+	if (err == HTTP_REAUTH && !large_request) {
+		credential_fill(&http_auth);
+		goto retry;
+	}
+	if (err != HTTP_OK)
+		err = -1;
+
+	if (!rpc->any_written)
+		err = -1;
+
+	curl_slist_free_all(headers);
+	free(gzip_body);
+	return err;
+}
+
+static int rpc_service(struct rpc_state *rpc, struct discovery *heads,
+		       const char **client_argv, const struct strbuf *preamble,
+		       struct strbuf *rpc_result)
+{
+	const char *svc = rpc->service_name;
+	struct strbuf buf = STRBUF_INIT;
+	struct child_process client = CHILD_PROCESS_INIT;
+	int err = 0;
+
+	client.in = -1;
+	client.out = -1;
+	client.git_cmd = 1;
+	client.argv = client_argv;
+	if (start_command(&client))
+		exit(1);
+	write_or_die(client.in, preamble->buf, preamble->len);
+	if (heads)
+		write_or_die(client.in, heads->buf, heads->len);
+
+	rpc->alloc = http_post_buffer;
+	rpc->buf = xmalloc(rpc->alloc);
+	rpc->in = client.in;
+	rpc->out = client.out;
+
+	strbuf_addf(&buf, "%s%s", url.buf, svc);
+	rpc->service_url = strbuf_detach(&buf, NULL);
+
+	strbuf_addf(&buf, "Content-Type: application/x-%s-request", svc);
+	rpc->hdr_content_type = strbuf_detach(&buf, NULL);
+
+	strbuf_addf(&buf, "Accept: application/x-%s-result", svc);
+	rpc->hdr_accept = strbuf_detach(&buf, NULL);
+
+	if (get_protocol_http_header(heads->version, &buf))
+		rpc->protocol_header = strbuf_detach(&buf, NULL);
+	else
+		rpc->protocol_header = NULL;
+
+	while (!err) {
+		int n = packet_read(rpc->out, NULL, NULL, rpc->buf, rpc->alloc, 0);
+		if (!n)
+			break;
+		rpc->pos = 0;
+		rpc->len = n;
+		err |= post_rpc(rpc, 0);
+	}
+
+	close(client.in);
+	client.in = -1;
+	if (!err) {
+		strbuf_read(rpc_result, client.out, 0);
+	} else {
+		char buf[4096];
+		for (;;)
+			if (xread(client.out, buf, sizeof(buf)) <= 0)
+				break;
+	}
+
+	close(client.out);
+	client.out = -1;
+
+	err |= finish_command(&client);
+	free(rpc->service_url);
+	free(rpc->hdr_content_type);
+	free(rpc->hdr_accept);
+	free(rpc->protocol_header);
+	free(rpc->buf);
+	strbuf_release(&buf);
+	return err;
+}
+
+static int fetch_dumb(int nr_heads, struct ref **to_fetch)
+{
+	struct walker *walker;
+	char **targets;
+	int ret, i;
+
+	ALLOC_ARRAY(targets, nr_heads);
+	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));
+
+	walker = get_http_walker(url.buf);
+	walker->get_verbosely = options.verbosity >= 3;
+	walker->get_recover = 0;
+	ret = walker_fetch(walker, nr_heads, targets, NULL, NULL);
+	walker_free(walker);
+
+	for (i = 0; i < nr_heads; i++)
+		free(targets[i]);
+	free(targets);
+
+	return ret ? error(_("fetch failed.")) : 0;
+}
+
+static int fetch_git(struct discovery *heads,
+	int nr_heads, struct ref **to_fetch)
+{
+	struct rpc_state rpc;
+	struct strbuf preamble = STRBUF_INIT;
+	int i, err;
+	struct argv_array args = ARGV_ARRAY_INIT;
+	struct strbuf rpc_result = STRBUF_INIT;
+
+	argv_array_pushl(&args, "fetch-pack", "--stateless-rpc",
+			 "--stdin", "--lock-pack", NULL);
+	if (options.followtags)
+		argv_array_push(&args, "--include-tag");
+	if (options.thin)
+		argv_array_push(&args, "--thin");
+	if (options.verbosity >= 3)
+		argv_array_pushl(&args, "-v", "-v", NULL);
+	if (options.check_self_contained_and_connected)
+		argv_array_push(&args, "--check-self-contained-and-connected");
+	if (options.cloning)
+		argv_array_push(&args, "--cloning");
+	if (options.update_shallow)
+		argv_array_push(&args, "--update-shallow");
+	if (!options.progress)
+		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);
+	for (i = 0; i < options.deepen_not.nr; i++)
+		argv_array_pushf(&args, "--shallow-exclude=%s",
+				 options.deepen_not.items[i].string);
+	if (options.deepen_relative && options.depth)
+		argv_array_push(&args, "--deepen-relative");
+	if (options.from_promisor)
+		argv_array_push(&args, "--from-promisor");
+	if (options.no_dependents)
+		argv_array_push(&args, "--no-dependents");
+	if (options.filter)
+		argv_array_pushf(&args, "--filter=%s", options.filter);
+	argv_array_push(&args, url.buf);
+
+	for (i = 0; i < nr_heads; i++) {
+		struct ref *ref = to_fetch[i];
+		if (!*ref->name)
+			die(_("cannot fetch by sha1 over smart http"));
+		packet_buf_write(&preamble, "%s %s\n",
+				 oid_to_hex(&ref->old_oid), ref->name);
+	}
+	packet_buf_flush(&preamble);
+
+	memset(&rpc, 0, sizeof(rpc));
+	rpc.service_name = "git-upload-pack",
+	rpc.gzip_request = 1;
+
+	err = rpc_service(&rpc, heads, args.argv, &preamble, &rpc_result);
+	if (rpc_result.len)
+		write_or_die(1, rpc_result.buf, rpc_result.len);
+	strbuf_release(&rpc_result);
+	strbuf_release(&preamble);
+	argv_array_clear(&args);
+	return err;
+}
+
+static int fetch(int nr_heads, struct ref **to_fetch)
+{
+	struct discovery *d = discover_refs("git-upload-pack", 0);
+	if (d->proto_git)
+		return fetch_git(d, nr_heads, to_fetch);
+	else
+		return fetch_dumb(nr_heads, to_fetch);
+}
+
+static void parse_fetch(struct strbuf *buf)
+{
+	struct ref **to_fetch = NULL;
+	struct ref *list_head = NULL;
+	struct ref **list = &list_head;
+	int alloc_heads = 0, nr_heads = 0;
+
+	do {
+		const char *p;
+		if (skip_prefix(buf->buf, "fetch ", &p)) {
+			const char *name;
+			struct ref *ref;
+			struct object_id old_oid;
+			const char *q;
+
+			if (parse_oid_hex(p, &old_oid, &q))
+				die(_("protocol error: expected sha/ref, got '%s'"), p);
+			if (*q == ' ')
+				name = q + 1;
+			else if (!*q)
+				name = "";
+			else
+				die(_("protocol error: expected sha/ref, got '%s'"), p);
+
+			ref = alloc_ref(name);
+			oidcpy(&ref->old_oid, &old_oid);
+
+			*list = ref;
+			list = &ref->next;
+
+			ALLOC_GROW(to_fetch, nr_heads + 1, alloc_heads);
+			to_fetch[nr_heads++] = ref;
+		}
+		else
+			die(_("http transport does not support %s"), buf->buf);
+
+		strbuf_reset(buf);
+		if (strbuf_getline_lf(buf, stdin) == EOF)
+			return;
+		if (!*buf->buf)
+			break;
+	} while (1);
+
+	if (fetch(nr_heads, to_fetch))
+		exit(128); /* error already reported */
+	free_refs(list_head);
+	free(to_fetch);
+
+	printf("\n");
+	fflush(stdout);
+	strbuf_reset(buf);
+}
+
+static int push_dav(int nr_spec, char **specs)
+{
+	struct child_process child = CHILD_PROCESS_INIT;
+	size_t i;
+
+	child.git_cmd = 1;
+	argv_array_push(&child.args, "http-push");
+	argv_array_push(&child.args, "--helper-status");
+	if (options.dry_run)
+		argv_array_push(&child.args, "--dry-run");
+	if (options.verbosity > 1)
+		argv_array_push(&child.args, "--verbose");
+	argv_array_push(&child.args, url.buf);
+	for (i = 0; i < nr_spec; i++)
+		argv_array_push(&child.args, specs[i]);
+
+	if (run_command(&child))
+		die(_("git-http-push failed"));
+	return 0;
+}
+
+static int push_git(struct discovery *heads, int nr_spec, char **specs)
+{
+	struct rpc_state rpc;
+	int i, err;
+	struct argv_array args;
+	struct string_list_item *cas_option;
+	struct strbuf preamble = STRBUF_INIT;
+	struct strbuf rpc_result = STRBUF_INIT;
+
+	argv_array_init(&args);
+	argv_array_pushl(&args, "send-pack", "--stateless-rpc", "--helper-status",
+			 NULL);
+
+	if (options.thin)
+		argv_array_push(&args, "--thin");
+	if (options.dry_run)
+		argv_array_push(&args, "--dry-run");
+	if (options.push_cert == SEND_PACK_PUSH_CERT_ALWAYS)
+		argv_array_push(&args, "--signed=yes");
+	else if (options.push_cert == SEND_PACK_PUSH_CERT_IF_ASKED)
+		argv_array_push(&args, "--signed=if-asked");
+	if (options.verbosity == 0)
+		argv_array_push(&args, "--quiet");
+	else if (options.verbosity > 1)
+		argv_array_push(&args, "--verbose");
+	for (i = 0; i < options.push_options.nr; i++)
+		argv_array_pushf(&args, "--push-option=%s",
+				 options.push_options.items[i].string);
+	argv_array_push(&args, options.progress ? "--progress" : "--no-progress");
+	for_each_string_list_item(cas_option, &cas_options)
+		argv_array_push(&args, cas_option->string);
+	argv_array_push(&args, url.buf);
+
+	argv_array_push(&args, "--stdin");
+	for (i = 0; i < nr_spec; i++)
+		packet_buf_write(&preamble, "%s\n", specs[i]);
+	packet_buf_flush(&preamble);
+
+	memset(&rpc, 0, sizeof(rpc));
+	rpc.service_name = "git-receive-pack",
+
+	err = rpc_service(&rpc, heads, args.argv, &preamble, &rpc_result);
+	if (rpc_result.len)
+		write_or_die(1, rpc_result.buf, rpc_result.len);
+	strbuf_release(&rpc_result);
+	strbuf_release(&preamble);
+	argv_array_clear(&args);
+	return err;
+}
+
+static int push(int nr_spec, char **specs)
+{
+	struct discovery *heads = discover_refs("git-receive-pack", 1);
+	int ret;
+
+	if (heads->proto_git)
+		ret = push_git(heads, nr_spec, specs);
+	else
+		ret = push_dav(nr_spec, specs);
+	free_discovery(heads);
+	return ret;
+}
+
+static void parse_push(struct strbuf *buf)
+{
+	char **specs = NULL;
+	int alloc_spec = 0, nr_spec = 0, i, ret;
+
+	do {
+		if (starts_with(buf->buf, "push ")) {
+			ALLOC_GROW(specs, nr_spec + 1, alloc_spec);
+			specs[nr_spec++] = xstrdup(buf->buf + 5);
+		}
+		else
+			die(_("http transport does not support %s"), buf->buf);
+
+		strbuf_reset(buf);
+		if (strbuf_getline_lf(buf, stdin) == EOF)
+			goto free_specs;
+		if (!*buf->buf)
+			break;
+	} while (1);
+
+	ret = push(nr_spec, specs);
+	printf("\n");
+	fflush(stdout);
+
+	if (ret)
+		exit(128); /* error already reported */
+
+ free_specs:
+	for (i = 0; i < nr_spec; i++)
+		free(specs[i]);
+	free(specs);
+}
+
+static int stateless_connect(const char *service_name)
+{
+	struct discovery *discover;
+	struct rpc_state rpc;
+	struct strbuf buf = STRBUF_INIT;
+
+	/*
+	 * Run the info/refs request and see if the server supports protocol
+	 * v2.  If and only if the server supports v2 can we successfully
+	 * establish a stateless connection, otherwise we need to tell the
+	 * client to fallback to using other transport helper functions to
+	 * complete their request.
+	 */
+	discover = discover_refs(service_name, 0);
+	if (discover->version != protocol_v2) {
+		printf("fallback\n");
+		fflush(stdout);
+		return -1;
+	} else {
+		/* Stateless Connection established */
+		printf("\n");
+		fflush(stdout);
+	}
+
+	rpc.service_name = service_name;
+	rpc.service_url = xstrfmt("%s%s", url.buf, rpc.service_name);
+	rpc.hdr_content_type = xstrfmt("Content-Type: application/x-%s-request", rpc.service_name);
+	rpc.hdr_accept = xstrfmt("Accept: application/x-%s-result", rpc.service_name);
+	if (get_protocol_http_header(discover->version, &buf)) {
+		rpc.protocol_header = strbuf_detach(&buf, NULL);
+	} else {
+		rpc.protocol_header = NULL;
+		strbuf_release(&buf);
+	}
+	rpc.buf = xmalloc(http_post_buffer);
+	rpc.alloc = http_post_buffer;
+	rpc.len = 0;
+	rpc.pos = 0;
+	rpc.in = 1;
+	rpc.out = 0;
+	rpc.any_written = 0;
+	rpc.gzip_request = 1;
+	rpc.initial_buffer = 0;
+	rpc.write_line_lengths = 1;
+	rpc.flush_read_but_not_sent = 0;
+
+	/*
+	 * Dump the capability listing that we got from the server earlier
+	 * during the info/refs request.
+	 */
+	write_or_die(rpc.in, discover->buf, discover->len);
+
+	/* Until we see EOF keep sending POSTs */
+	while (1) {
+		size_t avail;
+		enum packet_read_status status;
+
+		if (!rpc_read_from_out(&rpc, PACKET_READ_GENTLE_ON_EOF, &avail,
+				       &status))
+			BUG("The entire rpc->buf should be larger than LARGE_PACKET_MAX");
+		if (status == PACKET_READ_EOF)
+			break;
+		if (post_rpc(&rpc, status == PACKET_READ_FLUSH))
+			/* We would have an err here */
+			break;
+		/* Reset the buffer for next request */
+		rpc.len = 0;
+	}
+
+	free(rpc.service_url);
+	free(rpc.hdr_content_type);
+	free(rpc.hdr_accept);
+	free(rpc.protocol_header);
+	free(rpc.buf);
+	strbuf_release(&buf);
+
+	return 0;
+}
+
+int cmd_main(int argc, const char **argv)
+{
+	struct strbuf buf = STRBUF_INIT;
+	int nongit;
+
+	setup_git_directory_gently(&nongit);
+	if (argc < 2) {
+		error(_("remote-curl: usage: git remote-curl <remote> [<url>]"));
+		return 1;
+	}
+
+	options.verbosity = 1;
+	options.progress = !!isatty(2);
+	options.thin = 1;
+	string_list_init(&options.deepen_not, 1);
+	string_list_init(&options.push_options, 1);
+
+	/*
+	 * Just report "remote-curl" here (folding all the various aliases
+	 * ("git-remote-http", "git-remote-https", and etc.) here since they
+	 * are all just copies of the same actual executable.
+	 */
+	trace2_cmd_name("remote-curl");
+
+	remote = remote_get(argv[1]);
+
+	if (argc > 2) {
+		end_url_with_slash(&url, argv[2]);
+	} else {
+		end_url_with_slash(&url, remote->url[0]);
+	}
+
+	http_init(remote, url.buf, 0);
+
+	do {
+		const char *arg;
+
+		if (strbuf_getline_lf(&buf, stdin) == EOF) {
+			if (ferror(stdin))
+				error(_("remote-curl: error reading command stream from git"));
+			return 1;
+		}
+		if (buf.len == 0)
+			break;
+		if (starts_with(buf.buf, "fetch ")) {
+			if (nongit)
+				die(_("remote-curl: fetch attempted without a local repo"));
+			parse_fetch(&buf);
+
+		} else if (!strcmp(buf.buf, "list") || starts_with(buf.buf, "list ")) {
+			int for_push = !!strstr(buf.buf + 4, "for-push");
+			output_refs(get_refs(for_push));
+
+		} else if (starts_with(buf.buf, "push ")) {
+			parse_push(&buf);
+
+		} else if (skip_prefix(buf.buf, "option ", &arg)) {
+			char *value = strchr(arg, ' ');
+			int result;
+
+			if (value)
+				*value++ = '\0';
+			else
+				value = "true";
+
+			result = set_option(arg, value);
+			if (!result)
+				printf("ok\n");
+			else if (result < 0)
+				printf("error invalid value\n");
+			else
+				printf("unsupported\n");
+			fflush(stdout);
+
+		} else if (!strcmp(buf.buf, "capabilities")) {
+			printf("stateless-connect\n");
+			printf("fetch\n");
+			printf("option\n");
+			printf("push\n");
+			printf("check-connectivity\n");
+			printf("\n");
+			fflush(stdout);
+		} else if (skip_prefix(buf.buf, "stateless-connect ", &arg)) {
+			if (!stateless_connect(arg))
+				break;
+		} else {
+			error(_("remote-curl: unknown command '%s' from git"), buf.buf);
+			return 1;
+		}
+		strbuf_reset(&buf);
+	} while (1);
+
+	http_cleanup();
+
+	return 0;
+}