Function git_connect

connect.c:1401–1500

* 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 * done, finish the connection with finish_connect() with the value returned * from this function (it is safe to call finish_connect() with NULL to * support the former case). * * If it returns, the connect is successful; it just dies on errors

 * the connection failed).
 */
struct child_process *git_connect(int fd[2], const char *url,
				  enum git_connect_service service,
				  const char *prog, int flags)
{
	char *hostandport, *path;
	struct child_process *conn;
	enum url_scheme scheme;
	enum protocol_version version = get_protocol_version_config();

	/*
	 * NEEDSWORK: If we are trying to use protocol v2 and we are planning
	 * to perform any operation that doesn't involve upload-pack (i.e., a
	 * fetch, ls-remote, etc), then fallback to v0 since we don't know how
	 * to do anything else (like push or remote archive) via v2.
	 */
	if (version == protocol_v2 && service != GIT_CONNECT_UPLOAD_PACK)
		version = protocol_v0;

	/* Without this we cannot rely on waitpid() to tell
	 * what happened to our children.
	 */
	signal(SIGCHLD, SIG_DFL);

	scheme = parse_connect_url(url, &hostandport, &path);
	if ((flags & CONNECT_DIAG_URL) && (scheme != URL_SCHEME_SSH)) {
		printf("Diag: url=%s\n", url ? url : "NULL");
		printf("Diag: protocol=%s\n", url_scheme_name(scheme));
		printf("Diag: hostandport=%s\n", hostandport ? hostandport : "NULL");
		printf("Diag: path=%s\n", path ? path : "NULL");
		conn = NULL;
	} else if (scheme == URL_SCHEME_GIT) {
		conn = git_connect_git(fd, hostandport, path, prog, version, flags);
		conn->trace2_child_class = "transport/git";
	} else {
		struct strbuf cmd = STRBUF_INIT;
		const char *const *var;

		conn = xmalloc(sizeof(*conn));
		child_process_init(conn);

		if (looks_like_command_line_option(path))
			die(_("strange pathname '%s' blocked"), path);

		strbuf_addstr(&cmd, prog);
		strbuf_addch(&cmd, ' ');
		sq_quote_buf(&cmd, path);

		/* remove repo-local variables from the environment */
		for (var = local_repo_env; *var; var++)
			strvec_push(&conn->env, *var);

		conn->use_shell = 1;
		conn->in = conn->out = -1;
		if (scheme == URL_SCHEME_SSH) {
			char *ssh_host = hostandport;
			const char *port = NULL;
			transport_check_allowed("ssh");
			get_host_and_port(&ssh_host, &port);