connect: split ssh command line options into separate function

The git_connect function is growing long.  Split the portion that
discovers an ssh command and options it accepts before the service
name and path to a separate function to make it easier to read.

No functional change intended.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

connect.c

@@ -919,6 +919,65 @@ static struct child_process *git_connect_git(int fd[2], char *hostandport,
 	return conn;
 }
 
+/* Prepare a child_process for use by Git's SSH-tunneled transport. */
+static void fill_ssh_args(struct child_process *conn, const char *ssh_host,
+			  const char *port, int flags)
+{
+	const char *ssh;
+	enum ssh_variant variant;
+
+	if (looks_like_command_line_option(ssh_host))
+		die("strange hostname '%s' blocked", ssh_host);
+
+	ssh = get_ssh_command();
+	if (ssh) {
+		variant = determine_ssh_variant(ssh, 1);
+	} else {
+		/*
+		 * GIT_SSH is the no-shell version of
+		 * GIT_SSH_COMMAND (and must remain so for
+		 * historical compatibility).
+		 */
+		conn->use_shell = 0;
+
+		ssh = getenv("GIT_SSH");
+		if (!ssh)
+			ssh = "ssh";
+		variant = determine_ssh_variant(ssh, 0);
+	}
+
+	argv_array_push(&conn->args, ssh);
+
+	if (variant == VARIANT_SSH &&
+	    get_protocol_version_config() > 0) {
+		argv_array_push(&conn->args, "-o");
+		argv_array_push(&conn->args, "SendEnv=" GIT_PROTOCOL_ENVIRONMENT);
+		argv_array_pushf(&conn->env_array, GIT_PROTOCOL_ENVIRONMENT "=version=%d",
+				 get_protocol_version_config());
+	}
+
+	if (variant != VARIANT_SIMPLE) {
+		if (flags & CONNECT_IPV4)
+			argv_array_push(&conn->args, "-4");
+		else if (flags & CONNECT_IPV6)
+			argv_array_push(&conn->args, "-6");
+	}
+
+	if (variant == VARIANT_TORTOISEPLINK)
+		argv_array_push(&conn->args, "-batch");
+
+	if (port && variant != VARIANT_SIMPLE) {
+		if (variant == VARIANT_SSH)
+			argv_array_push(&conn->args, "-p");
+		else
+			argv_array_push(&conn->args, "-P");
+
+		argv_array_push(&conn->args, port);
+	}
+
+	argv_array_push(&conn->args, ssh_host);
+}
+
 /*
  * This returns the dummy child_process `no_fork` if the transport protocol
  * does not need fork(2), or a struct child_process object if it does.  Once
@@ -972,8 +1031,6 @@ struct child_process *git_connect(int fd[2], const char *url,
 		conn->use_shell = 1;
 		conn->in = conn->out = -1;
 		if (protocol == PROTO_SSH) {
-			const char *ssh;
-			enum ssh_variant variant;
 			char *ssh_host = hostandport;
 			const char *port = NULL;
 			transport_check_allowed("ssh");
@@ -995,57 +1052,7 @@ struct child_process *git_connect(int fd[2], const char *url,
 				strbuf_release(&cmd);
 				return NULL;
 			}
-
+			fill_ssh_args(conn, ssh_host, port, flags);
-			if (looks_like_command_line_option(ssh_host))
-				die("strange hostname '%s' blocked", ssh_host);
-
-			ssh = get_ssh_command();
-			if (ssh) {
-				variant = determine_ssh_variant(ssh, 1);
-			} else {
-				/*
-				 * GIT_SSH is the no-shell version of
-				 * GIT_SSH_COMMAND (and must remain so for
-				 * historical compatibility).
-				 */
-				conn->use_shell = 0;
-
-				ssh = getenv("GIT_SSH");
-				if (!ssh)
-					ssh = "ssh";
-				variant = determine_ssh_variant(ssh, 0);
-			}
-
-			argv_array_push(&conn->args, ssh);
-
-			if (variant == VARIANT_SSH &&
-			    get_protocol_version_config() > 0) {
-				argv_array_push(&conn->args, "-o");
-				argv_array_push(&conn->args, "SendEnv=" GIT_PROTOCOL_ENVIRONMENT);
-				argv_array_pushf(&conn->env_array, GIT_PROTOCOL_ENVIRONMENT "=version=%d",
-						 get_protocol_version_config());
-			}
-
-			if (variant != VARIANT_SIMPLE) {
-				if (flags & CONNECT_IPV4)
-					argv_array_push(&conn->args, "-4");
-				else if (flags & CONNECT_IPV6)
-					argv_array_push(&conn->args, "-6");
-			}
-
-			if (variant == VARIANT_TORTOISEPLINK)
-				argv_array_push(&conn->args, "-batch");
-
-			if (port && variant != VARIANT_SIMPLE) {
-				if (variant == VARIANT_SSH)
-					argv_array_push(&conn->args, "-p");
-				else
-					argv_array_push(&conn->args, "-P");
-
-				argv_array_push(&conn->args, port);
-			}
-
-			argv_array_push(&conn->args, ssh_host);
 		} else {
 			transport_check_allowed("file");
 			if (get_protocol_version_config() > 0) {