push: accept push options

This implements everything that is required on the client side to make use
of push options from the porcelain push command.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-push.txt

@@ -11,7 +11,7 @@ SYNOPSIS
 [verse]
 'git push' [--all | --mirror | --tags] [--follow-tags] [--atomic] [-n | --dry-run] [--receive-pack=<git-receive-pack>]
 	   [--repo=<repository>] [-f | --force] [-d | --delete] [--prune] [-v | --verbose]
-	   [-u | --set-upstream]
+	   [-u | --set-upstream] [--push-option=<string>]
 	   [--[no-]signed|--sign=(true|false|if-asked)]
 	   [--force-with-lease[=<refname>[:<expect>]]]
 	   [--no-verify] [<repository> [<refspec>...]]
@@ -156,6 +156,12 @@ already exists on the remote side.
 	Either all refs are updated, or on error, no refs are updated.
 	If the server does not support atomic pushes the push will fail.
 
+-o::
+--push-option::
+	Transmit the given string to the server, which passes them to
+	the pre-receive as well as the post-receive hook. The given string
+	must not contain a NUL or LF character.
+
 --receive-pack=<git-receive-pack>::
 --exec=<git-receive-pack>::
 	Path to the 'git-receive-pack' program on the remote

builtin/push.c

@@ -353,7 +353,8 @@ static int push_with_options(struct transport *transport, int flags)
 	return 1;
 }
 
-static int do_push(const char *repo, int flags)
+static int do_push(const char *repo, int flags,
+		   const struct string_list *push_options)
 {
 	int i, errs;
 	struct remote *remote = pushremote_get(repo);
@@ -376,6 +377,9 @@ static int do_push(const char *repo, int flags)
 	if (remote->mirror)
 		flags |= (TRANSPORT_PUSH_MIRROR|TRANSPORT_PUSH_FORCE);
 
+	if (push_options->nr)
+		flags |= TRANSPORT_PUSH_OPTIONS;
+
 	if ((flags & TRANSPORT_PUSH_ALL) && refspec) {
 		if (!strcmp(*refspec, "refs/tags/*"))
 			return error(_("--all and --tags are incompatible"));
@@ -406,13 +410,16 @@ static int do_push(const char *repo, int flags)
 		for (i = 0; i < url_nr; i++) {
 			struct transport *transport =
 				transport_get(remote, url[i]);
+			if (flags & TRANSPORT_PUSH_OPTIONS)
+				transport->push_options = push_options;
 			if (push_with_options(transport, flags))
 				errs++;
 		}
 	} else {
 		struct transport *transport =
 			transport_get(remote, NULL);
-
+		if (flags & TRANSPORT_PUSH_OPTIONS)
+			transport->push_options = push_options;
 		if (push_with_options(transport, flags))
 			errs++;
 	}
@@ -500,6 +507,9 @@ int cmd_push(int argc, const char **argv, const char *prefix)
 	int push_cert = -1;
 	int rc;
 	const char *repo = NULL;	/* default repository */
+	static struct string_list push_options = STRING_LIST_INIT_DUP;
+	static struct string_list_item *item;
+
 	struct option options[] = {
 		OPT__VERBOSITY(&verbosity),
 		OPT_STRING( 0 , "repo", &repo, N_("repository"), N_("repository")),
@@ -533,6 +543,7 @@ int cmd_push(int argc, const char **argv, const char *prefix)
 		  0, "signed", &push_cert, "yes|no|if-asked", N_("GPG sign the push"),
 		  PARSE_OPT_OPTARG, option_parse_push_signed },
 		OPT_BIT(0, "atomic", &flags, N_("request atomic transaction on remote side"), TRANSPORT_PUSH_ATOMIC),
+		OPT_STRING_LIST('o', "push-option", &push_options, N_("server-specific"), N_("option to transmit")),
 		OPT_SET_INT('4', "ipv4", &family, N_("use IPv4 addresses only"),
 				TRANSPORT_FAMILY_IPV4),
 		OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
@@ -563,7 +574,11 @@ int cmd_push(int argc, const char **argv, const char *prefix)
 		set_refspecs(argv + 1, argc - 1, repo);
 	}
 
-	rc = do_push(repo, flags);
+	for_each_string_list_item(item, &push_options)
+		if (strchr(item->string, '\n'))
+			die(_("push options must not have new line characters"));
+
+	rc = do_push(repo, flags, &push_options);
 	if (rc == -1)
 		usage_with_options(push_usage, options);
 	else

send-pack.c

@@ -260,6 +260,7 @@ static int generate_push_cert(struct strbuf *req_buf,
 			      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;
@@ -276,6 +277,9 @@ static int generate_push_cert(struct strbuf *req_buf,
 	}
 	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) {
@@ -370,6 +374,8 @@ int send_pack(struct send_pack_args *args,
 	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;
@@ -392,6 +398,8 @@ int send_pack(struct send_pack_args *args,
 		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;
@@ -418,6 +426,11 @@ int send_pack(struct send_pack_args *args,
 
 	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)
@@ -426,6 +439,8 @@ int send_pack(struct send_pack_args *args,
 		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());
 
@@ -512,6 +527,18 @@ int send_pack(struct send_pack_args *args,
 	strbuf_release(&req_buf);
 	strbuf_release(&cap_buf);
 
+	if (use_push_options) {
+		struct string_list_item *item;
+		struct strbuf sb = STRBUF_INIT;
+
+		for_each_string_list_item(item, args->push_options)
+			packet_buf_write(&sb, "%s", item->string);
+
+		write_or_die(out, sb.buf, sb.len);
+		packet_flush(out);
+		strbuf_release(&sb);
+	}
+
 	if (use_sideband && cmds_sent) {
 		memset(&demux, 0, sizeof(demux));
 		demux.proc = sideband_demux;

send-pack.h

@@ -1,6 +1,8 @@
 #ifndef SEND_PACK_H
 #define SEND_PACK_H
 
+#include "string-list.h"
+
 /* Possible values for push_cert field in send_pack_args. */
 #define SEND_PACK_PUSH_CERT_NEVER 0
 #define SEND_PACK_PUSH_CERT_IF_ASKED 1
@@ -21,6 +23,7 @@ struct send_pack_args {
 		push_cert:2,
 		stateless_rpc:1,
 		atomic:1;
+	const struct string_list *push_options;
 };
 
 struct option;

transport.c

@@ -510,6 +510,7 @@ static int git_transport_push(struct transport *transport, struct ref *remote_re
 	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)

transport.h

@@ -48,6 +48,12 @@ struct transport {
 	 */
 	unsigned cloning : 1;
 
+	/*
+	 * These strings will be passed to the {pre, post}-receive hook,
+	 * on the remote side, if both sides support the push options capability.
+	 */
+	const struct string_list *push_options;
+
 	/**
 	 * Returns 0 if successful, positive if the option is not
 	 * recognized or is inapplicable, and negative if the option
@@ -134,6 +140,7 @@ struct transport {
 #define TRANSPORT_PUSH_CERT_ALWAYS 2048
 #define TRANSPORT_PUSH_CERT_IF_ASKED 4096
 #define TRANSPORT_PUSH_ATOMIC 8192
+#define TRANSPORT_PUSH_OPTIONS 16384
 
 #define TRANSPORT_SUMMARY_WIDTH (2 * DEFAULT_ABBREV + 3)
 #define TRANSPORT_SUMMARY(x) (int)(TRANSPORT_SUMMARY_WIDTH + strlen(x) - gettext_width(x)), (x)