gistfile1.c

static VALUE
ossl_start_ssl(VALUE self, int (*func)())
{
    SSL *ssl;
    OpenFile *fptr;
    int ret;

    Data_Get_Struct(self, SSL, ssl);
    GetOpenFile(ossl_ssl_get_io(self), fptr);
    for(;;){
	if((ret = func(ssl)) > 0) break;
	switch(ssl_get_error(ssl, ret)){
	case SSL_ERROR_WANT_WRITE:
            rb_io_wait_writable(fileno(fptr->f));
            continue;
	case SSL_ERROR_WANT_READ:
            rb_io_wait_readable(fileno(fptr->f));
            continue;
	case SSL_ERROR_SYSCALL:
	    if (errno) rb_sys_fail(0); /* an error occurs here */
	default:
	    ossl_raise(eSSLError, NULL);
	}
    }

    return self;
}