1/*
2 * ntp_fp.h - definitions for NTP fixed/floating-point arithmetic
3 */
4
5#ifndef NTP_FP_H
6#define NTP_FP_H
7
8#include <sys/types.h>
9#include <sys/socket.h>
10#include <netinet/in.h>
11
12#include "ntp_rfc2553.h"
13
14#include "ntp_types.h"
15
16/*
17 * NTP uses two fixed point formats.  The first (l_fp) is the "long"
18 * format and is 64 bits long with the decimal between bits 31 and 32.
19 * This is used for time stamps in the NTP packet header (in network
20 * byte order) and for internal computations of offsets (in local host
21 * byte order). We use the same structure for both signed and unsigned
22 * values, which is a big hack but saves rewriting all the operators
23 * twice. Just to confuse this, we also sometimes just carry the
24 * fractional part in calculations, in both signed and unsigned forms.
25 * Anyway, an l_fp looks like:
26 *
27 *    0			  1		      2			  3
28 *    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
29 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
30 *   |			       Integral Part			     |
31 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
32 *   |			       Fractional Part			     |
33 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
34 *
35 */
36typedef struct {
37	union {
38		u_int32 Xl_ui;
39		int32 Xl_i;
40	} Ul_i;
41	union {
42		u_int32 Xl_uf;
43		int32 Xl_f;
44	} Ul_f;
45} l_fp;
46
47#define l_ui	Ul_i.Xl_ui		/* unsigned integral part */
48#define	l_i	Ul_i.Xl_i		/* signed integral part */
49#define	l_uf	Ul_f.Xl_uf		/* unsigned fractional part */
50#define	l_f	Ul_f.Xl_f		/* signed fractional part */
51
52/*
53 * Fractional precision (of an l_fp) is actually the number of
54 * bits in a long.
55 */
56#define	FRACTION_PREC	(32)
57
58
59/*
60 * The second fixed point format is 32 bits, with the decimal between
61 * bits 15 and 16.  There is a signed version (s_fp) and an unsigned
62 * version (u_fp).  This is used to represent synchronizing distance
63 * and synchronizing dispersion in the NTP packet header (again, in
64 * network byte order) and internally to hold both distance and
65 * dispersion values (in local byte order).  In network byte order
66 * it looks like:
67 *
68 *    0			  1		      2			  3
69 *    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
70 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
71 *   |		  Integer Part	     |	   Fraction Part	     |
72 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
73 *
74 */
75typedef int32 s_fp;
76typedef u_int32 u_fp;
77
78/*
79 * A unit second in fp format.  Actually 2**(half_the_bits_in_a_long)
80 */
81#define	FP_SECOND	(0x10000)
82
83/*
84 * Byte order conversions
85 */
86#define	HTONS_FP(x)	(htonl(x))
87#define	HTONL_FP(h, n)	do { (n)->l_ui = htonl((h)->l_ui); \
88			     (n)->l_uf = htonl((h)->l_uf); } while (0)
89#define	NTOHS_FP(x)	(ntohl(x))
90#define	NTOHL_FP(n, h)	do { (h)->l_ui = ntohl((n)->l_ui); \
91			     (h)->l_uf = ntohl((n)->l_uf); } while (0)
92#define	NTOHL_MFP(ni, nf, hi, hf) \
93	do { (hi) = ntohl(ni); (hf) = ntohl(nf); } while (0)
94#define	HTONL_MFP(hi, hf, ni, nf) \
95	do { (ni) = ntohl(hi); (nf) = ntohl(hf); } while (0)
96
97/* funny ones.  Converts ts fractions to net order ts */
98#define	HTONL_UF(uf, nts) \
99	do { (nts)->l_ui = 0; (nts)->l_uf = htonl(uf); } while (0)
100#define	HTONL_F(f, nts) do { (nts)->l_uf = htonl(f); \
101				if ((f) & 0x80000000) \
102					(nts)->l_i = -1; \
103				else \
104					(nts)->l_i = 0; \
105			} while (0)
106
107/*
108 * Conversions between the two fixed point types
109 */
110#define	MFPTOFP(x_i, x_f)	(((x_i) >= 0x00010000) ? 0x7fffffff : \
111				(((x_i) <= -0x00010000) ? 0x80000000 : \
112				(((x_i)<<16) | (((x_f)>>16)&0xffff))))
113#define	LFPTOFP(v)		MFPTOFP((v)->l_i, (v)->l_f)
114
115#define UFPTOLFP(x, v) ((v)->l_ui = (u_fp)(x)>>16, (v)->l_uf = (x)<<16)
116#define FPTOLFP(x, v)  (UFPTOLFP((x), (v)), (x) < 0 ? (v)->l_ui -= 0x10000 : 0)
117
118#define MAXLFP(v) ((v)->l_ui = 0x7fffffff, (v)->l_uf = 0xffffffff)
119#define MINLFP(v) ((v)->l_ui = 0x80000000, (v)->l_uf = 0)
120
121/*
122 * Primitive operations on long fixed point values.  If these are
123 * reminiscent of assembler op codes it's only because some may
124 * be replaced by inline assembler for particular machines someday.
125 * These are the (kind of inefficient) run-anywhere versions.
126 */
127#define	M_NEG(v_i, v_f) 	/* v = -v */ \
128	do { \
129		if ((v_f) == 0) \
130			(v_i) = -((s_fp)(v_i)); \
131		else { \
132			(v_f) = -((s_fp)(v_f)); \
133			(v_i) = ~(v_i); \
134		} \
135	} while(0)
136
137#define	M_NEGM(r_i, r_f, a_i, a_f) 	/* r = -a */ \
138	do { \
139		if ((a_f) == 0) { \
140			(r_f) = 0; \
141			(r_i) = -(a_i); \
142		} else { \
143			(r_f) = -(a_f); \
144			(r_i) = ~(a_i); \
145		} \
146	} while(0)
147
148#define M_ADD(r_i, r_f, a_i, a_f) 	/* r += a */ \
149	do { \
150		register u_int32 lo_tmp; \
151		register u_int32 hi_tmp; \
152		\
153		lo_tmp = ((r_f) & 0xffff) + ((a_f) & 0xffff); \
154		hi_tmp = (((r_f) >> 16) & 0xffff) + (((a_f) >> 16) & 0xffff); \
155		if (lo_tmp & 0x10000) \
156			hi_tmp++; \
157		(r_f) = ((hi_tmp & 0xffff) << 16) | (lo_tmp & 0xffff); \
158		\
159		(r_i) += (a_i); \
160		if (hi_tmp & 0x10000) \
161			(r_i)++; \
162	} while (0)
163
164#define M_ADD3(r_ovr, r_i, r_f, a_ovr, a_i, a_f) /* r += a, three word */ \
165	do { \
166		register u_int32 lo_tmp; \
167		register u_int32 hi_tmp; \
168		\
169		lo_tmp = ((r_f) & 0xffff) + ((a_f) & 0xffff); \
170		hi_tmp = (((r_f) >> 16) & 0xffff) + (((a_f) >> 16) & 0xffff); \
171		if (lo_tmp & 0x10000) \
172			hi_tmp++; \
173		(r_f) = ((hi_tmp & 0xffff) << 16) | (lo_tmp & 0xffff); \
174		\
175		lo_tmp = ((r_i) & 0xffff) + ((a_i) & 0xffff); \
176		if (hi_tmp & 0x10000) \
177			lo_tmp++; \
178		hi_tmp = (((r_i) >> 16) & 0xffff) + (((a_i) >> 16) & 0xffff); \
179		if (lo_tmp & 0x10000) \
180			hi_tmp++; \
181		(r_i) = ((hi_tmp & 0xffff) << 16) | (lo_tmp & 0xffff); \
182		\
183		(r_ovr) += (a_ovr); \
184		if (hi_tmp & 0x10000) \
185			(r_ovr)++; \
186	} while (0)
187
188#define M_SUB(r_i, r_f, a_i, a_f)	/* r -= a */ \
189	do { \
190		register u_int32 lo_tmp; \
191		register u_int32 hi_tmp; \
192		\
193		if ((a_f) == 0) { \
194			(r_i) -= (a_i); \
195		} else { \
196			lo_tmp = ((r_f) & 0xffff) + ((-((s_fp)(a_f))) & 0xffff); \
197			hi_tmp = (((r_f) >> 16) & 0xffff) \
198			    + (((-((s_fp)(a_f))) >> 16) & 0xffff); \
199			if (lo_tmp & 0x10000) \
200				hi_tmp++; \
201			(r_f) = ((hi_tmp & 0xffff) << 16) | (lo_tmp & 0xffff); \
202			\
203			(r_i) += ~(a_i); \
204			if (hi_tmp & 0x10000) \
205				(r_i)++; \
206		} \
207	} while (0)
208
209#define	M_RSHIFTU(v_i, v_f)		/* v >>= 1, v is unsigned */ \
210	do { \
211		(v_f) = (u_int32)(v_f) >> 1; \
212		if ((v_i) & 01) \
213			(v_f) |= 0x80000000; \
214		(v_i) = (u_int32)(v_i) >> 1; \
215	} while (0)
216
217#define	M_RSHIFT(v_i, v_f)		/* v >>= 1, v is signed */ \
218	do { \
219		(v_f) = (u_int32)(v_f) >> 1; \
220		if ((v_i) & 01) \
221			(v_f) |= 0x80000000; \
222		if ((v_i) & 0x80000000) \
223			(v_i) = ((v_i) >> 1) | 0x80000000; \
224		else \
225			(v_i) = (v_i) >> 1; \
226	} while (0)
227
228#define	M_LSHIFT(v_i, v_f)		/* v <<= 1 */ \
229	do { \
230		(v_i) <<= 1; \
231		if ((v_f) & 0x80000000) \
232			(v_i) |= 0x1; \
233		(v_f) <<= 1; \
234	} while (0)
235
236#define	M_LSHIFT3(v_ovr, v_i, v_f)	/* v <<= 1, with overflow */ \
237	do { \
238		(v_ovr) <<= 1; \
239		if ((v_i) & 0x80000000) \
240			(v_ovr) |= 0x1; \
241		(v_i) <<= 1; \
242		if ((v_f) & 0x80000000) \
243			(v_i) |= 0x1; \
244		(v_f) <<= 1; \
245	} while (0)
246
247#define	M_ADDUF(r_i, r_f, uf) 		/* r += uf, uf is u_int32 fraction */ \
248	M_ADD((r_i), (r_f), 0, (uf))	/* let optimizer worry about it */
249
250#define	M_SUBUF(r_i, r_f, uf)		/* r -= uf, uf is u_int32 fraction */ \
251	M_SUB((r_i), (r_f), 0, (uf))	/* let optimizer worry about it */
252
253#define	M_ADDF(r_i, r_f, f)		/* r += f, f is a int32 fraction */ \
254	do { \
255		if ((f) > 0) \
256			M_ADD((r_i), (r_f), 0, (f)); \
257		else if ((f) < 0) \
258			M_ADD((r_i), (r_f), (-1), (f));\
259	} while(0)
260
261#define	M_ISNEG(v_i, v_f) 		/* v < 0 */ \
262	(((v_i) & 0x80000000) != 0)
263
264#define	M_ISHIS(a_i, a_f, b_i, b_f)	/* a >= b unsigned */ \
265	(((u_int32)(a_i)) > ((u_int32)(b_i)) || \
266	  ((a_i) == (b_i) && ((u_int32)(a_f)) >= ((u_int32)(b_f))))
267
268#define	M_ISGEQ(a_i, a_f, b_i, b_f)	/* a >= b signed */ \
269	(((int32)(a_i)) > ((int32)(b_i)) || \
270	  ((a_i) == (b_i) && ((u_int32)(a_f)) >= ((u_int32)(b_f))))
271
272#define	M_ISEQU(a_i, a_f, b_i, b_f)	/* a == b unsigned */ \
273	((a_i) == (b_i) && (a_f) == (b_f))
274
275/*
276 * Operations on the long fp format
277 */
278#define	L_ADD(r, a)	M_ADD((r)->l_ui, (r)->l_uf, (a)->l_ui, (a)->l_uf)
279#define	L_SUB(r, a)	M_SUB((r)->l_ui, (r)->l_uf, (a)->l_ui, (a)->l_uf)
280#define	L_NEG(v)	M_NEG((v)->l_ui, (v)->l_uf)
281#define L_ADDUF(r, uf)	M_ADDUF((r)->l_ui, (r)->l_uf, (uf))
282#define L_SUBUF(r, uf)	M_SUBUF((r)->l_ui, (r)->l_uf, (uf))
283#define	L_ADDF(r, f)	M_ADDF((r)->l_ui, (r)->l_uf, (f))
284#define	L_RSHIFT(v)	M_RSHIFT((v)->l_i, (v)->l_uf)
285#define	L_RSHIFTU(v)	M_RSHIFTU((v)->l_ui, (v)->l_uf)
286#define	L_LSHIFT(v)	M_LSHIFT((v)->l_ui, (v)->l_uf)
287#define	L_CLR(v)	((v)->l_ui = (v)->l_uf = 0)
288
289#define	L_ISNEG(v)	(((v)->l_ui & 0x80000000) != 0)
290#define L_ISZERO(v)	((v)->l_ui == 0 && (v)->l_uf == 0)
291#define	L_ISHIS(a, b)	((a)->l_ui > (b)->l_ui || \
292			  ((a)->l_ui == (b)->l_ui && (a)->l_uf >= (b)->l_uf))
293#define	L_ISGEQ(a, b)	((a)->l_i > (b)->l_i || \
294			  ((a)->l_i == (b)->l_i && (a)->l_uf >= (b)->l_uf))
295#define	L_ISEQU(a, b)	M_ISEQU((a)->l_ui, (a)->l_uf, (b)->l_ui, (b)->l_uf)
296
297/*
298 * s_fp/double and u_fp/double conversions
299 */
300#define FRIC		65536.	 		/* 2^16 as a double */
301#define DTOFP(r)	((s_fp)((r) * FRIC))
302#define DTOUFP(r)	((u_fp)((r) * FRIC))
303#define FPTOD(r)	((double)(r) / FRIC)
304
305/*
306 * l_fp/double conversions
307 */
308#define FRAC		4294967296. 		/* 2^32 as a double */
309#define M_DTOLFP(d, r_i, r_uf) 			/* double to l_fp */ \
310	do { \
311		register double d_tmp; \
312		\
313		d_tmp = (d); \
314		if (d_tmp < 0) { \
315			d_tmp = -d_tmp; \
316			(r_i) = (int32)(d_tmp); \
317			(r_uf) = (u_int32)(((d_tmp) - (double)(r_i)) * FRAC); \
318			M_NEG((r_i), (r_uf)); \
319		} else { \
320			(r_i) = (int32)(d_tmp); \
321			(r_uf) = (u_int32)(((d_tmp) - (double)(r_i)) * FRAC); \
322		} \
323	} while (0)
324#define M_LFPTOD(r_i, r_uf, d) 			/* l_fp to double */ \
325	do { \
326		register l_fp l_tmp; \
327		\
328		l_tmp.l_i = (r_i); \
329		l_tmp.l_f = (r_uf); \
330		if (l_tmp.l_i < 0) { \
331			M_NEG(l_tmp.l_i, l_tmp.l_uf); \
332			(d) = -((double)l_tmp.l_i + ((double)l_tmp.l_uf) / FRAC); \
333		} else { \
334			(d) = (double)l_tmp.l_i + ((double)l_tmp.l_uf) / FRAC; \
335		} \
336	} while (0)
337#define DTOLFP(d, v) 	M_DTOLFP((d), (v)->l_ui, (v)->l_uf)
338#define LFPTOD(v, d) 	M_LFPTOD((v)->l_ui, (v)->l_uf, (d))
339
340/*
341 * Prototypes
342 */
343extern	char *	dofptoa		P((u_fp, int, short, int));
344extern	char *	dolfptoa	P((u_long, u_long, int, short, int));
345
346extern	int	atolfp		P((const char *, l_fp *));
347extern	int	buftvtots	P((const char *, l_fp *));
348extern	char *	fptoa		P((s_fp, short));
349extern	char *	fptoms		P((s_fp, short));
350extern	int	hextolfp	P((const char *, l_fp *));
351extern  void    gpstolfp        P((int, int, unsigned long, l_fp *));
352extern	int	mstolfp		P((const char *, l_fp *));
353extern	char *	prettydate	P((l_fp *));
354extern	char *	gmprettydate	P((l_fp *));
355extern	char *	uglydate	P((l_fp *));
356extern  void    mfp_mul         P((int32 *, u_int32 *, int32, u_int32, int32, u_int32));
357
358extern	void	get_systime	P((l_fp *));
359extern	int	step_systime	P((double));
360extern	int	adj_systime	P((double));
361
362extern	struct tm * ntp2unix_tm P((u_long ntp, int local));
363
364#define	lfptoa(_fpv, _ndec)	mfptoa((_fpv)->l_ui, (_fpv)->l_uf, (_ndec))
365#define	lfptoms(_fpv, _ndec)	mfptoms((_fpv)->l_ui, (_fpv)->l_uf, (_ndec))
366
367#define stoa(_sin)	socktoa((_sin))
368#define stohost(_sin)	socktohost((_sin))
369
370#define	ntoa(_sin)	stoa(_sin)
371#define	ntohost(_sin)	stohost(_sin)
372
373#define	ufptoa(_fpv, _ndec)	dofptoa((_fpv), 0, (_ndec), 0)
374#define	ufptoms(_fpv, _ndec)	dofptoa((_fpv), 0, (_ndec), 1)
375#define	ulfptoa(_fpv, _ndec)	dolfptoa((_fpv)->l_ui, (_fpv)->l_uf, 0, (_ndec), 0)
376#define	ulfptoms(_fpv, _ndec)	dolfptoa((_fpv)->l_ui, (_fpv)->l_uf, 0, (_ndec), 1)
377#define	umfptoa(_fpi, _fpf, _ndec) dolfptoa((_fpi), (_fpf), 0, (_ndec), 0)
378
379#endif /* NTP_FP_H */
380