1#include <config.h>
2
3#include <ntp.h>
4#include <ntp_fp.h>
5#include <refidsmear.h>
6
7/*
8 * we want to test a refid format of:
9 * 254.x.y.x
10 *
11 * where x.y.z are 24 bits containing 2 (signed) integer bits
12 * and 22 fractional bits.
13 *
14 */
15
16
17l_fp
18convertRefIDToLFP(uint32_t r)
19{
20	l_fp temp;
21
22	r = ntohl(r);
23
24	// printf("%03d %08x: ", (r >> 24) & 0xFF, (r & 0x00FFFFFF) );
25
26	temp.l_uf = (r << 10);	/* 22 fractional bits */
27
28	temp.l_ui = (r >> 22) & 0x3;
29	temp.l_ui |= ~(temp.l_ui & 2) + 1;
30
31	return temp;
32}
33
34
35uint32_t
36convertLFPToRefID(l_fp num)
37{
38	uint32_t temp;
39
40	/* round the input with the highest bit to shift out from the
41	 * fraction, then keep just two bits from the integral part.
42	 *
43	 * TODO: check for overflows; should we clamp/saturate or just
44	 * complain?
45	 */
46	L_ADDUF(&num, 0x200);
47	num.l_ui &= 3;
48
49	/* combine integral and fractional part to 24 bits */
50	temp  = (num.l_ui << 22) | (num.l_uf >> 10);
51
52	/* put in the leading 254.0.0.0 */
53	temp |= UINT32_C(0xFE000000);
54
55	// printf("%03d %08x: ", (temp >> 24) & 0xFF, (temp & 0x00FFFFFF) );
56
57	return htonl(temp);
58}
59