Function pqGetline3

src/interfaces/libpq/fe-protocol3.c:1952–1997

* PQgetline - gets a newline-terminated string from the backend. * * See fe-exec.c for documentation. */

 * See fe-exec.c for documentation.
 */
int
pqGetline3(PGconn *conn, char *s, int maxlen)
{
	int			status;

	if (conn->sock == PGINVALID_SOCKET ||
		(conn->asyncStatus != PGASYNC_COPY_OUT &&
		 conn->asyncStatus != PGASYNC_COPY_BOTH) ||
		conn->copy_is_binary)
	{
		appendPQExpBufferStr(&conn->errorMessage,
							 libpq_gettext("PQgetline: not doing text COPY OUT\n"));
		*s = '\0';
		return EOF;
	}

	while ((status = PQgetlineAsync(conn, s, maxlen - 1)) == 0)
	{
		/* need to load more data */
		if (pqWait(true, false, conn) ||
			pqReadData(conn) < 0)
		{
			*s = '\0';
			return EOF;
		}
	}

	if (status < 0)
	{
		/* End of copy detected; gin up old-style terminator */
		strcpy(s, "\\.");
		return 0;
	}

	/* Add null terminator, and strip trailing \n if present */
	if (s[status - 1] == '\n')
	{
		s[status - 1] = '\0';
		return 0;
	}
	else
	{
		s[status] = '\0';
		return 1;
	}
}

/*
 * PQgetlineAsync - gets a COPY data row without blocking.