Squashed 'third_party/git/' content from commit cb71568594

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

1 files changed, 627 insertions, 0 deletions

diff --git a/send-pack.c b/send-pack.c
new file mode 100644
index 000000000000..6dc16c321163
--- /dev/null
+++ b/send-pack.c
@@ -0,0 +1,627 @@
+#include "builtin.h"
+#include "config.h"
+#include "commit.h"
+#include "refs.h"
+#include "object-store.h"
+#include "pkt-line.h"
+#include "sideband.h"
+#include "run-command.h"
+#include "remote.h"
+#include "connect.h"
+#include "send-pack.h"
+#include "quote.h"
+#include "transport.h"
+#include "version.h"
+#include "sha1-array.h"
+#include "gpg-interface.h"
+#include "cache.h"
+
+int option_parse_push_signed(const struct option *opt,
+			     const char *arg, int unset)
+{
+	if (unset) {
+		*(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
+		return 0;
+	}
+	switch (git_parse_maybe_bool(arg)) {
+	case 1:
+		*(int *)(opt->value) = SEND_PACK_PUSH_CERT_ALWAYS;
+		return 0;
+	case 0:
+		*(int *)(opt->value) = SEND_PACK_PUSH_CERT_NEVER;
+		return 0;
+	}
+	if (!strcasecmp("if-asked", arg)) {
+		*(int *)(opt->value) = SEND_PACK_PUSH_CERT_IF_ASKED;
+		return 0;
+	}
+	die("bad %s argument: %s", opt->long_name, arg);
+}
+
+static void feed_object(const struct object_id *oid, FILE *fh, int negative)
+{
+	if (negative && !has_object_file(oid))
+		return;
+
+	if (negative)
+		putc('^', fh);
+	fputs(oid_to_hex(oid), fh);
+	putc('\n', fh);
+}
+
+/*
+ * Make a pack stream and spit it out into file descriptor fd
+ */
+static int pack_objects(int fd, struct ref *refs, struct oid_array *extra, struct send_pack_args *args)
+{
+	/*
+	 * The child becomes pack-objects --revs; we feed
+	 * the revision parameters to it via its stdin and
+	 * let its stdout go back to the other end.
+	 */
+	struct child_process po = CHILD_PROCESS_INIT;
+	FILE *po_in;
+	int i;
+	int rc;
+
+	argv_array_push(&po.args, "pack-objects");
+	argv_array_push(&po.args, "--all-progress-implied");
+	argv_array_push(&po.args, "--revs");
+	argv_array_push(&po.args, "--stdout");
+	if (args->use_thin_pack)
+		argv_array_push(&po.args, "--thin");
+	if (args->use_ofs_delta)
+		argv_array_push(&po.args, "--delta-base-offset");
+	if (args->quiet || !args->progress)
+		argv_array_push(&po.args, "-q");
+	if (args->progress)
+		argv_array_push(&po.args, "--progress");
+	if (is_repository_shallow(the_repository))
+		argv_array_push(&po.args, "--shallow");
+	po.in = -1;
+	po.out = args->stateless_rpc ? -1 : fd;
+	po.git_cmd = 1;
+	if (start_command(&po))
+		die_errno("git pack-objects failed");
+
+	/*
+	 * We feed the pack-objects we just spawned with revision
+	 * parameters by writing to the pipe.
+	 */
+	po_in = xfdopen(po.in, "w");
+	for (i = 0; i < extra->nr; i++)
+		feed_object(&extra->oid[i], po_in, 1);
+
+	while (refs) {
+		if (!is_null_oid(&refs->old_oid))
+			feed_object(&refs->old_oid, po_in, 1);
+		if (!is_null_oid(&refs->new_oid))
+			feed_object(&refs->new_oid, po_in, 0);
+		refs = refs->next;
+	}
+
+	fflush(po_in);
+	if (ferror(po_in))
+		die_errno("error writing to pack-objects");
+	fclose(po_in);
+
+	if (args->stateless_rpc) {
+		char *buf = xmalloc(LARGE_PACKET_MAX);
+		while (1) {
+			ssize_t n = xread(po.out, buf, LARGE_PACKET_MAX);
+			if (n <= 0)
+				break;
+			send_sideband(fd, -1, buf, n, LARGE_PACKET_MAX);
+		}
+		free(buf);
+		close(po.out);
+		po.out = -1;
+	}
+
+	rc = finish_command(&po);
+	if (rc) {
+		/*
+		 * For a normal non-zero exit, we assume pack-objects wrote
+		 * something useful to stderr. For death by signal, though,
+		 * we should mention it to the user. The exception is SIGPIPE
+		 * (141), because that's a normal occurrence if the remote end
+		 * hangs up (and we'll report that by trying to read the unpack
+		 * status).
+		 */
+		if (rc > 128 && rc != 141)
+			error("pack-objects died of signal %d", rc - 128);
+		return -1;
+	}
+	return 0;
+}
+
+static int receive_unpack_status(struct packet_reader *reader)
+{
+	if (packet_reader_read(reader) != PACKET_READ_NORMAL)
+		return error(_("unexpected flush packet while reading remote unpack status"));
+	if (!skip_prefix(reader->line, "unpack ", &reader->line))
+		return error(_("unable to parse remote unpack status: %s"), reader->line);
+	if (strcmp(reader->line, "ok"))
+		return error(_("remote unpack failed: %s"), reader->line);
+	return 0;
+}
+
+static int receive_status(struct packet_reader *reader, struct ref *refs)
+{
+	struct ref *hint;
+	int ret;
+
+	hint = NULL;
+	ret = receive_unpack_status(reader);
+	while (1) {
+		const char *refname;
+		char *msg;
+		if (packet_reader_read(reader) != PACKET_READ_NORMAL)
+			break;
+		if (!starts_with(reader->line, "ok ") && !starts_with(reader->line, "ng ")) {
+			error("invalid ref status from remote: %s", reader->line);
+			ret = -1;
+			break;
+		}
+
+		refname = reader->line + 3;
+		msg = strchr(refname, ' ');
+		if (msg)
+			*msg++ = '\0';
+
+		/* first try searching at our hint, falling back to all refs */
+		if (hint)
+			hint = find_ref_by_name(hint, refname);
+		if (!hint)
+			hint = find_ref_by_name(refs, refname);
+		if (!hint) {
+			warning("remote reported status on unknown ref: %s",
+					refname);
+			continue;
+		}
+		if (hint->status != REF_STATUS_EXPECTING_REPORT) {
+			warning("remote reported status on unexpected ref: %s",
+					refname);
+			continue;
+		}
+
+		if (reader->line[0] == 'o' && reader->line[1] == 'k')
+			hint->status = REF_STATUS_OK;
+		else {
+			hint->status = REF_STATUS_REMOTE_REJECT;
+			ret = -1;
+		}
+		hint->remote_status = xstrdup_or_null(msg);
+		/* start our next search from the next ref */
+		hint = hint->next;
+	}
+	return ret;
+}
+
+static int sideband_demux(int in, int out, void *data)
+{
+	int *fd = data, ret;
+	if (async_with_fork())
+		close(fd[1]);
+	ret = recv_sideband("send-pack", fd[0], out);
+	close(out);
+	return ret;
+}
+
+static int advertise_shallow_grafts_cb(const struct commit_graft *graft, void *cb)
+{
+	struct strbuf *sb = cb;
+	if (graft->nr_parent == -1)
+		packet_buf_write(sb, "shallow %s\n", oid_to_hex(&graft->oid));
+	return 0;
+}
+
+static void advertise_shallow_grafts_buf(struct strbuf *sb)
+{
+	if (!is_repository_shallow(the_repository))
+		return;
+	for_each_commit_graft(advertise_shallow_grafts_cb, sb);
+}
+
+#define CHECK_REF_NO_PUSH -1
+#define CHECK_REF_STATUS_REJECTED -2
+#define CHECK_REF_UPTODATE -3
+static int check_to_send_update(const struct ref *ref, const struct send_pack_args *args)
+{
+	if (!ref->peer_ref && !args->send_mirror)
+		return CHECK_REF_NO_PUSH;
+
+	/* Check for statuses set by set_ref_status_for_push() */
+	switch (ref->status) {
+	case REF_STATUS_REJECT_NONFASTFORWARD:
+	case REF_STATUS_REJECT_ALREADY_EXISTS:
+	case REF_STATUS_REJECT_FETCH_FIRST:
+	case REF_STATUS_REJECT_NEEDS_FORCE:
+	case REF_STATUS_REJECT_STALE:
+	case REF_STATUS_REJECT_NODELETE:
+		return CHECK_REF_STATUS_REJECTED;
+	case REF_STATUS_UPTODATE:
+		return CHECK_REF_UPTODATE;
+	default:
+		return 0;
+	}
+}
+
+/*
+ * the beginning of the next line, or the end of buffer.
+ *
+ * NEEDSWORK: perhaps move this to git-compat-util.h or somewhere and
+ * convert many similar uses found by "git grep -A4 memchr".
+ */
+static const char *next_line(const char *line, size_t len)
+{
+	const char *nl = memchr(line, '\n', len);
+	if (!nl)
+		return line + len; /* incomplete line */
+	return nl + 1;
+}
+
+static int generate_push_cert(struct strbuf *req_buf,
+			      const struct ref *remote_refs,
+			      struct send_pack_args *args,
+			      const char *cap_string,
+			      const char *push_cert_nonce)
+{
+	const struct ref *ref;
+	struct string_list_item *item;
+	char *signing_key = xstrdup(get_signing_key());
+	const char *cp, *np;
+	struct strbuf cert = STRBUF_INIT;
+	int update_seen = 0;
+
+	strbuf_addstr(&cert, "certificate version 0.1\n");
+	strbuf_addf(&cert, "pusher %s ", signing_key);
+	datestamp(&cert);
+	strbuf_addch(&cert, '\n');
+	if (args->url && *args->url) {
+		char *anon_url = transport_anonymize_url(args->url);
+		strbuf_addf(&cert, "pushee %s\n", anon_url);
+		free(anon_url);
+	}
+	if (push_cert_nonce[0])
+		strbuf_addf(&cert, "nonce %s\n", push_cert_nonce);
+	if (args->push_options)
+		for_each_string_list_item(item, args->push_options)
+			strbuf_addf(&cert, "push-option %s\n", item->string);
+	strbuf_addstr(&cert, "\n");
+
+	for (ref = remote_refs; ref; ref = ref->next) {
+		if (check_to_send_update(ref, args) < 0)
+			continue;
+		update_seen = 1;
+		strbuf_addf(&cert, "%s %s %s\n",
+			    oid_to_hex(&ref->old_oid),
+			    oid_to_hex(&ref->new_oid),
+			    ref->name);
+	}
+	if (!update_seen)
+		goto free_return;
+
+	if (sign_buffer(&cert, &cert, signing_key))
+		die(_("failed to sign the push certificate"));
+
+	packet_buf_write(req_buf, "push-cert%c%s", 0, cap_string);
+	for (cp = cert.buf; cp < cert.buf + cert.len; cp = np) {
+		np = next_line(cp, cert.buf + cert.len - cp);
+		packet_buf_write(req_buf,
+				 "%.*s", (int)(np - cp), cp);
+	}
+	packet_buf_write(req_buf, "push-cert-end\n");
+
+free_return:
+	free(signing_key);
+	strbuf_release(&cert);
+	return update_seen;
+}
+
+
+static int atomic_push_failure(struct send_pack_args *args,
+			       struct ref *remote_refs,
+			       struct ref *failing_ref)
+{
+	struct ref *ref;
+	/* Mark other refs as failed */
+	for (ref = remote_refs; ref; ref = ref->next) {
+		if (!ref->peer_ref && !args->send_mirror)
+			continue;
+
+		switch (ref->status) {
+		case REF_STATUS_EXPECTING_REPORT:
+			ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
+			continue;
+		default:
+			break; /* do nothing */
+		}
+	}
+	return error("atomic push failed for ref %s. status: %d\n",
+		     failing_ref->name, failing_ref->status);
+}
+
+#define NONCE_LEN_LIMIT 256
+
+static void reject_invalid_nonce(const char *nonce, int len)
+{
+	int i = 0;
+
+	if (NONCE_LEN_LIMIT <= len)
+		die("the receiving end asked to sign an invalid nonce <%.*s>",
+		    len, nonce);
+
+	for (i = 0; i < len; i++) {
+		int ch = nonce[i] & 0xFF;
+		if (isalnum(ch) ||
+		    ch == '-' || ch == '.' ||
+		    ch == '/' || ch == '+' ||
+		    ch == '=' || ch == '_')
+			continue;
+		die("the receiving end asked to sign an invalid nonce <%.*s>",
+		    len, nonce);
+	}
+}
+
+int send_pack(struct send_pack_args *args,
+	      int fd[], struct child_process *conn,
+	      struct ref *remote_refs,
+	      struct oid_array *extra_have)
+{
+	int in = fd[0];
+	int out = fd[1];
+	struct strbuf req_buf = STRBUF_INIT;
+	struct strbuf cap_buf = STRBUF_INIT;
+	struct ref *ref;
+	int need_pack_data = 0;
+	int allow_deleting_refs = 0;
+	int status_report = 0;
+	int use_sideband = 0;
+	int quiet_supported = 0;
+	int agent_supported = 0;
+	int use_atomic = 0;
+	int atomic_supported = 0;
+	int use_push_options = 0;
+	int push_options_supported = 0;
+	unsigned cmds_sent = 0;
+	int ret;
+	struct async demux;
+	const char *push_cert_nonce = NULL;
+	struct packet_reader reader;
+
+	/* Does the other end support the reporting? */
+	if (server_supports("report-status"))
+		status_report = 1;
+	if (server_supports("delete-refs"))
+		allow_deleting_refs = 1;
+	if (server_supports("ofs-delta"))
+		args->use_ofs_delta = 1;
+	if (server_supports("side-band-64k"))
+		use_sideband = 1;
+	if (server_supports("quiet"))
+		quiet_supported = 1;
+	if (server_supports("agent"))
+		agent_supported = 1;
+	if (server_supports("no-thin"))
+		args->use_thin_pack = 0;
+	if (server_supports("atomic"))
+		atomic_supported = 1;
+	if (server_supports("push-options"))
+		push_options_supported = 1;
+
+	if (args->push_cert != SEND_PACK_PUSH_CERT_NEVER) {
+		int len;
+		push_cert_nonce = server_feature_value("push-cert", &len);
+		if (push_cert_nonce) {
+			reject_invalid_nonce(push_cert_nonce, len);
+			push_cert_nonce = xmemdupz(push_cert_nonce, len);
+		} else if (args->push_cert == SEND_PACK_PUSH_CERT_ALWAYS) {
+			die(_("the receiving end does not support --signed push"));
+		} else if (args->push_cert == SEND_PACK_PUSH_CERT_IF_ASKED) {
+			warning(_("not sending a push certificate since the"
+				  " receiving end does not support --signed"
+				  " push"));
+		}
+	}
+
+	if (!remote_refs) {
+		fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
+			"Perhaps you should specify a branch such as 'master'.\n");
+		return 0;
+	}
+	if (args->atomic && !atomic_supported)
+		die(_("the receiving end does not support --atomic push"));
+
+	use_atomic = atomic_supported && args->atomic;
+
+	if (args->push_options && !push_options_supported)
+		die(_("the receiving end does not support push options"));
+
+	use_push_options = push_options_supported && args->push_options;
+
+	if (status_report)
+		strbuf_addstr(&cap_buf, " report-status");
+	if (use_sideband)
+		strbuf_addstr(&cap_buf, " side-band-64k");
+	if (quiet_supported && (args->quiet || !args->progress))
+		strbuf_addstr(&cap_buf, " quiet");
+	if (use_atomic)
+		strbuf_addstr(&cap_buf, " atomic");
+	if (use_push_options)
+		strbuf_addstr(&cap_buf, " push-options");
+	if (agent_supported)
+		strbuf_addf(&cap_buf, " agent=%s", git_user_agent_sanitized());
+
+	/*
+	 * NEEDSWORK: why does delete-refs have to be so specific to
+	 * send-pack machinery that set_ref_status_for_push() cannot
+	 * set this bit for us???
+	 */
+	for (ref = remote_refs; ref; ref = ref->next)
+		if (ref->deletion && !allow_deleting_refs)
+			ref->status = REF_STATUS_REJECT_NODELETE;
+
+	if (!args->dry_run)
+		advertise_shallow_grafts_buf(&req_buf);
+
+	if (!args->dry_run && push_cert_nonce)
+		cmds_sent = generate_push_cert(&req_buf, remote_refs, args,
+					       cap_buf.buf, push_cert_nonce);
+
+	/*
+	 * Clear the status for each ref and see if we need to send
+	 * the pack data.
+	 */
+	for (ref = remote_refs; ref; ref = ref->next) {
+		switch (check_to_send_update(ref, args)) {
+		case 0: /* no error */
+			break;
+		case CHECK_REF_STATUS_REJECTED:
+			/*
+			 * When we know the server would reject a ref update if
+			 * we were to send it and we're trying to send the refs
+			 * atomically, abort the whole operation.
+			 */
+			if (use_atomic) {
+				strbuf_release(&req_buf);
+				strbuf_release(&cap_buf);
+				return atomic_push_failure(args, remote_refs, ref);
+			}
+			/* else fallthrough */
+		default:
+			continue;
+		}
+		if (!ref->deletion)
+			need_pack_data = 1;
+
+		if (args->dry_run || !status_report)
+			ref->status = REF_STATUS_OK;
+		else
+			ref->status = REF_STATUS_EXPECTING_REPORT;
+	}
+
+	/*
+	 * Finally, tell the other end!
+	 */
+	for (ref = remote_refs; ref; ref = ref->next) {
+		char *old_hex, *new_hex;
+
+		if (args->dry_run || push_cert_nonce)
+			continue;
+
+		if (check_to_send_update(ref, args) < 0)
+			continue;
+
+		old_hex = oid_to_hex(&ref->old_oid);
+		new_hex = oid_to_hex(&ref->new_oid);
+		if (!cmds_sent) {
+			packet_buf_write(&req_buf,
+					 "%s %s %s%c%s",
+					 old_hex, new_hex, ref->name, 0,
+					 cap_buf.buf);
+			cmds_sent = 1;
+		} else {
+			packet_buf_write(&req_buf, "%s %s %s",
+					 old_hex, new_hex, ref->name);
+		}
+	}
+
+	if (use_push_options) {
+		struct string_list_item *item;
+
+		packet_buf_flush(&req_buf);
+		for_each_string_list_item(item, args->push_options)
+			packet_buf_write(&req_buf, "%s", item->string);
+	}
+
+	if (args->stateless_rpc) {
+		if (!args->dry_run && (cmds_sent || is_repository_shallow(the_repository))) {
+			packet_buf_flush(&req_buf);
+			send_sideband(out, -1, req_buf.buf, req_buf.len, LARGE_PACKET_MAX);
+		}
+	} else {
+		write_or_die(out, req_buf.buf, req_buf.len);
+		packet_flush(out);
+	}
+	strbuf_release(&req_buf);
+	strbuf_release(&cap_buf);
+
+	if (use_sideband && cmds_sent) {
+		memset(&demux, 0, sizeof(demux));
+		demux.proc = sideband_demux;
+		demux.data = fd;
+		demux.out = -1;
+		demux.isolate_sigpipe = 1;
+		if (start_async(&demux))
+			die("send-pack: unable to fork off sideband demultiplexer");
+		in = demux.out;
+	}
+
+	packet_reader_init(&reader, in, NULL, 0,
+			   PACKET_READ_CHOMP_NEWLINE |
+			   PACKET_READ_DIE_ON_ERR_PACKET);
+
+	if (need_pack_data && cmds_sent) {
+		if (pack_objects(out, remote_refs, extra_have, args) < 0) {
+			for (ref = remote_refs; ref; ref = ref->next)
+				ref->status = REF_STATUS_NONE;
+			if (args->stateless_rpc)
+				close(out);
+			if (git_connection_is_socket(conn))
+				shutdown(fd[0], SHUT_WR);
+
+			/*
+			 * Do not even bother with the return value; we know we
+			 * are failing, and just want the error() side effects.
+			 */
+			if (status_report)
+				receive_unpack_status(&reader);
+
+			if (use_sideband) {
+				close(demux.out);
+				finish_async(&demux);
+			}
+			fd[1] = -1;
+			return -1;
+		}
+		if (!args->stateless_rpc)
+			/* Closed by pack_objects() via start_command() */
+			fd[1] = -1;
+	}
+	if (args->stateless_rpc && cmds_sent)
+		packet_flush(out);
+
+	if (status_report && cmds_sent)
+		ret = receive_status(&reader, remote_refs);
+	else
+		ret = 0;
+	if (args->stateless_rpc)
+		packet_flush(out);
+
+	if (use_sideband && cmds_sent) {
+		close(demux.out);
+		if (finish_async(&demux)) {
+			error("error in sideband demultiplexer");
+			ret = -1;
+		}
+	}
+
+	if (ret < 0)
+		return ret;
+
+	if (args->porcelain)
+		return 0;
+
+	for (ref = remote_refs; 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;
+}