diff options
Diffstat (limited to 'include/ntp_fp.h')
-rw-r--r-- | include/ntp_fp.h | 376 |
1 files changed, 376 insertions, 0 deletions
diff --git a/include/ntp_fp.h b/include/ntp_fp.h new file mode 100644 index 0000000..256bab8 --- /dev/null +++ b/include/ntp_fp.h @@ -0,0 +1,376 @@ +/* + * ntp_fp.h - definitions for NTP fixed/floating-point arithmetic + */ + +#ifndef NTP_FP_H +#define NTP_FP_H + +#include <sys/types.h> +#include <sys/socket.h> +#include "ntp_rfc2553.h" +#include <netinet/in.h> + +#include "ntp_types.h" + +/* + * NTP uses two fixed point formats. The first (l_fp) is the "long" + * format and is 64 bits long with the decimal between bits 31 and 32. + * This is used for time stamps in the NTP packet header (in network + * byte order) and for internal computations of offsets (in local host + * byte order). We use the same structure for both signed and unsigned + * values, which is a big hack but saves rewriting all the operators + * twice. Just to confuse this, we also sometimes just carry the + * fractional part in calculations, in both signed and unsigned forms. + * Anyway, an l_fp looks like: + * + * 0 1 2 3 + * 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 + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Integral Part | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Fractional Part | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * + */ +typedef struct { + union { + u_int32 Xl_ui; + int32 Xl_i; + } Ul_i; + union { + u_int32 Xl_uf; + int32 Xl_f; + } Ul_f; +} l_fp; + +#define l_ui Ul_i.Xl_ui /* unsigned integral part */ +#define l_i Ul_i.Xl_i /* signed integral part */ +#define l_uf Ul_f.Xl_uf /* unsigned fractional part */ +#define l_f Ul_f.Xl_f /* signed fractional part */ + +/* + * Fractional precision (of an l_fp) is actually the number of + * bits in a long. + */ +#define FRACTION_PREC (32) + + +/* + * The second fixed point format is 32 bits, with the decimal between + * bits 15 and 16. There is a signed version (s_fp) and an unsigned + * version (u_fp). This is used to represent synchronizing distance + * and synchronizing dispersion in the NTP packet header (again, in + * network byte order) and internally to hold both distance and + * dispersion values (in local byte order). In network byte order + * it looks like: + * + * 0 1 2 3 + * 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 + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Integer Part | Fraction Part | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * + */ +typedef int32 s_fp; +typedef u_int32 u_fp; + +/* + * A unit second in fp format. Actually 2**(half_the_bits_in_a_long) + */ +#define FP_SECOND (0x10000) + +/* + * Byte order conversions + */ +#define HTONS_FP(x) (htonl(x)) +#define HTONL_FP(h, n) do { (n)->l_ui = htonl((h)->l_ui); \ + (n)->l_uf = htonl((h)->l_uf); } while (0) +#define NTOHS_FP(x) (ntohl(x)) +#define NTOHL_FP(n, h) do { (h)->l_ui = ntohl((n)->l_ui); \ + (h)->l_uf = ntohl((n)->l_uf); } while (0) +#define NTOHL_MFP(ni, nf, hi, hf) \ + do { (hi) = ntohl(ni); (hf) = ntohl(nf); } while (0) +#define HTONL_MFP(hi, hf, ni, nf) \ + do { (ni) = ntohl(hi); (nf) = ntohl(hf); } while (0) + +/* funny ones. Converts ts fractions to net order ts */ +#define HTONL_UF(uf, nts) \ + do { (nts)->l_ui = 0; (nts)->l_uf = htonl(uf); } while (0) +#define HTONL_F(f, nts) do { (nts)->l_uf = htonl(f); \ + if ((f) & 0x80000000) \ + (nts)->l_i = -1; \ + else \ + (nts)->l_i = 0; \ + } while (0) + +/* + * Conversions between the two fixed point types + */ +#define MFPTOFP(x_i, x_f) (((x_i) >= 0x00010000) ? 0x7fffffff : \ + (((x_i) <= -0x00010000) ? 0x80000000 : \ + (((x_i)<<16) | (((x_f)>>16)&0xffff)))) +#define LFPTOFP(v) MFPTOFP((v)->l_i, (v)->l_f) + +#define UFPTOLFP(x, v) ((v)->l_ui = (u_fp)(x)>>16, (v)->l_uf = (x)<<16) +#define FPTOLFP(x, v) (UFPTOLFP((x), (v)), (x) < 0 ? (v)->l_ui -= 0x10000 : 0) + +#define MAXLFP(v) ((v)->l_ui = 0x7fffffff, (v)->l_uf = 0xffffffff) +#define MINLFP(v) ((v)->l_ui = 0x80000000, (v)->l_uf = 0) + +/* + * Primitive operations on long fixed point values. If these are + * reminiscent of assembler op codes it's only because some may + * be replaced by inline assembler for particular machines someday. + * These are the (kind of inefficient) run-anywhere versions. + */ +#define M_NEG(v_i, v_f) /* v = -v */ \ + do { \ + if ((v_f) == 0) \ + (v_i) = -((s_fp)(v_i)); \ + else { \ + (v_f) = -((s_fp)(v_f)); \ + (v_i) = ~(v_i); \ + } \ + } while(0) + +#define M_NEGM(r_i, r_f, a_i, a_f) /* r = -a */ \ + do { \ + if ((a_f) == 0) { \ + (r_f) = 0; \ + (r_i) = -(a_i); \ + } else { \ + (r_f) = -(a_f); \ + (r_i) = ~(a_i); \ + } \ + } while(0) + +#define M_ADD(r_i, r_f, a_i, a_f) /* r += a */ \ + do { \ + register u_int32 lo_tmp; \ + register u_int32 hi_tmp; \ + \ + lo_tmp = ((r_f) & 0xffff) + ((a_f) & 0xffff); \ + hi_tmp = (((r_f) >> 16) & 0xffff) + (((a_f) >> 16) & 0xffff); \ + if (lo_tmp & 0x10000) \ + hi_tmp++; \ + (r_f) = ((hi_tmp & 0xffff) << 16) | (lo_tmp & 0xffff); \ + \ + (r_i) += (a_i); \ + if (hi_tmp & 0x10000) \ + (r_i)++; \ + } while (0) + +#define M_ADD3(r_ovr, r_i, r_f, a_ovr, a_i, a_f) /* r += a, three word */ \ + do { \ + register u_int32 lo_tmp; \ + register u_int32 hi_tmp; \ + \ + lo_tmp = ((r_f) & 0xffff) + ((a_f) & 0xffff); \ + hi_tmp = (((r_f) >> 16) & 0xffff) + (((a_f) >> 16) & 0xffff); \ + if (lo_tmp & 0x10000) \ + hi_tmp++; \ + (r_f) = ((hi_tmp & 0xffff) << 16) | (lo_tmp & 0xffff); \ + \ + lo_tmp = ((r_i) & 0xffff) + ((a_i) & 0xffff); \ + if (hi_tmp & 0x10000) \ + lo_tmp++; \ + hi_tmp = (((r_i) >> 16) & 0xffff) + (((a_i) >> 16) & 0xffff); \ + if (lo_tmp & 0x10000) \ + hi_tmp++; \ + (r_i) = ((hi_tmp & 0xffff) << 16) | (lo_tmp & 0xffff); \ + \ + (r_ovr) += (a_ovr); \ + if (hi_tmp & 0x10000) \ + (r_ovr)++; \ + } while (0) + +#define M_SUB(r_i, r_f, a_i, a_f) /* r -= a */ \ + do { \ + register u_int32 lo_tmp; \ + register u_int32 hi_tmp; \ + \ + if ((a_f) == 0) { \ + (r_i) -= (a_i); \ + } else { \ + lo_tmp = ((r_f) & 0xffff) + ((-((s_fp)(a_f))) & 0xffff); \ + hi_tmp = (((r_f) >> 16) & 0xffff) \ + + (((-((s_fp)(a_f))) >> 16) & 0xffff); \ + if (lo_tmp & 0x10000) \ + hi_tmp++; \ + (r_f) = ((hi_tmp & 0xffff) << 16) | (lo_tmp & 0xffff); \ + \ + (r_i) += ~(a_i); \ + if (hi_tmp & 0x10000) \ + (r_i)++; \ + } \ + } while (0) + +#define M_RSHIFTU(v_i, v_f) /* v >>= 1, v is unsigned */ \ + do { \ + (v_f) = (u_int32)(v_f) >> 1; \ + if ((v_i) & 01) \ + (v_f) |= 0x80000000; \ + (v_i) = (u_int32)(v_i) >> 1; \ + } while (0) + +#define M_RSHIFT(v_i, v_f) /* v >>= 1, v is signed */ \ + do { \ + (v_f) = (u_int32)(v_f) >> 1; \ + if ((v_i) & 01) \ + (v_f) |= 0x80000000; \ + if ((v_i) & 0x80000000) \ + (v_i) = ((v_i) >> 1) | 0x80000000; \ + else \ + (v_i) = (v_i) >> 1; \ + } while (0) + +#define M_LSHIFT(v_i, v_f) /* v <<= 1 */ \ + do { \ + (v_i) <<= 1; \ + if ((v_f) & 0x80000000) \ + (v_i) |= 0x1; \ + (v_f) <<= 1; \ + } while (0) + +#define M_LSHIFT3(v_ovr, v_i, v_f) /* v <<= 1, with overflow */ \ + do { \ + (v_ovr) <<= 1; \ + if ((v_i) & 0x80000000) \ + (v_ovr) |= 0x1; \ + (v_i) <<= 1; \ + if ((v_f) & 0x80000000) \ + (v_i) |= 0x1; \ + (v_f) <<= 1; \ + } while (0) + +#define M_ADDUF(r_i, r_f, uf) /* r += uf, uf is u_int32 fraction */ \ + M_ADD((r_i), (r_f), 0, (uf)) /* let optimizer worry about it */ + +#define M_SUBUF(r_i, r_f, uf) /* r -= uf, uf is u_int32 fraction */ \ + M_SUB((r_i), (r_f), 0, (uf)) /* let optimizer worry about it */ + +#define M_ADDF(r_i, r_f, f) /* r += f, f is a int32 fraction */ \ + do { \ + if ((f) > 0) \ + M_ADD((r_i), (r_f), 0, (f)); \ + else if ((f) < 0) \ + M_ADD((r_i), (r_f), (-1), (f));\ + } while(0) + +#define M_ISNEG(v_i, v_f) /* v < 0 */ \ + (((v_i) & 0x80000000) != 0) + +#define M_ISHIS(a_i, a_f, b_i, b_f) /* a >= b unsigned */ \ + (((u_int32)(a_i)) > ((u_int32)(b_i)) || \ + ((a_i) == (b_i) && ((u_int32)(a_f)) >= ((u_int32)(b_f)))) + +#define M_ISGEQ(a_i, a_f, b_i, b_f) /* a >= b signed */ \ + (((int32)(a_i)) > ((int32)(b_i)) || \ + ((a_i) == (b_i) && ((u_int32)(a_f)) >= ((u_int32)(b_f)))) + +#define M_ISEQU(a_i, a_f, b_i, b_f) /* a == b unsigned */ \ + ((a_i) == (b_i) && (a_f) == (b_f)) + +/* + * Operations on the long fp format + */ +#define L_ADD(r, a) M_ADD((r)->l_ui, (r)->l_uf, (a)->l_ui, (a)->l_uf) +#define L_SUB(r, a) M_SUB((r)->l_ui, (r)->l_uf, (a)->l_ui, (a)->l_uf) +#define L_NEG(v) M_NEG((v)->l_ui, (v)->l_uf) +#define L_ADDUF(r, uf) M_ADDUF((r)->l_ui, (r)->l_uf, (uf)) +#define L_SUBUF(r, uf) M_SUBUF((r)->l_ui, (r)->l_uf, (uf)) +#define L_ADDF(r, f) M_ADDF((r)->l_ui, (r)->l_uf, (f)) +#define L_RSHIFT(v) M_RSHIFT((v)->l_i, (v)->l_uf) +#define L_RSHIFTU(v) M_RSHIFT((v)->l_ui, (v)->l_uf) +#define L_LSHIFT(v) M_LSHIFT((v)->l_ui, (v)->l_uf) +#define L_CLR(v) ((v)->l_ui = (v)->l_uf = 0) + +#define L_ISNEG(v) (((v)->l_ui & 0x80000000) != 0) +#define L_ISZERO(v) ((v)->l_ui == 0 && (v)->l_uf == 0) +#define L_ISHIS(a, b) ((a)->l_ui > (b)->l_ui || \ + ((a)->l_ui == (b)->l_ui && (a)->l_uf >= (b)->l_uf)) +#define L_ISGEQ(a, b) ((a)->l_i > (b)->l_i || \ + ((a)->l_i == (b)->l_i && (a)->l_uf >= (b)->l_uf)) +#define L_ISEQU(a, b) M_ISEQU((a)->l_ui, (a)->l_uf, (b)->l_ui, (b)->l_uf) + +/* + * s_fp/double and u_fp/double conversions + */ +#define FRIC 65536. /* 2^16 as a double */ +#define DTOFP(r) ((s_fp)((r) * FRIC)) +#define DTOUFP(r) ((u_fp)((r) * FRIC)) +#define FPTOD(r) ((double)(r) / FRIC) + +/* + * l_fp/double conversions + */ +#define FRAC 4294967296. /* 2^32 as a double */ +#define M_DTOLFP(d, r_i, r_uf) /* double to l_fp */ \ + do { \ + register double d_tmp; \ + \ + d_tmp = (d); \ + if (d_tmp < 0) { \ + d_tmp = -d_tmp; \ + (r_i) = (int32)(d_tmp); \ + (r_uf) = (u_int32)(((d_tmp) - (double)(r_i)) * FRAC); \ + M_NEG((r_i), (r_uf)); \ + } else { \ + (r_i) = (int32)(d_tmp); \ + (r_uf) = (u_int32)(((d_tmp) - (double)(r_i)) * FRAC); \ + } \ + } while (0) +#define M_LFPTOD(r_i, r_uf, d) /* l_fp to double */ \ + do { \ + register l_fp l_tmp; \ + \ + l_tmp.l_i = (r_i); \ + l_tmp.l_f = (r_uf); \ + if (l_tmp.l_i < 0) { \ + M_NEG(l_tmp.l_i, l_tmp.l_uf); \ + (d) = -((double)l_tmp.l_i + ((double)l_tmp.l_uf) / FRAC); \ + } else { \ + (d) = (double)l_tmp.l_i + ((double)l_tmp.l_uf) / FRAC; \ + } \ + } while (0) +#define DTOLFP(d, v) M_DTOLFP((d), (v)->l_ui, (v)->l_uf) +#define LFPTOD(v, d) M_LFPTOD((v)->l_ui, (v)->l_uf, (d)) + +/* + * Prototypes + */ +extern char * dofptoa P((u_fp, int, short, int)); +extern char * dolfptoa P((u_long, u_long, int, short, int)); + +extern int atolfp P((const char *, l_fp *)); +extern int buftvtots P((const char *, l_fp *)); +extern char * fptoa P((s_fp, short)); +extern char * fptoms P((s_fp, short)); +extern int hextolfp P((const char *, l_fp *)); +extern void gpstolfp P((int, int, unsigned long, l_fp *)); +extern int mstolfp P((const char *, l_fp *)); +extern char * prettydate P((l_fp *)); +extern char * gmprettydate P((l_fp *)); +extern char * uglydate P((l_fp *)); +extern void mfp_mul P((int32 *, u_int32 *, int32, u_int32, int32, u_int32)); + +extern void get_systime P((l_fp *)); +extern int step_systime P((double)); +extern int adj_systime P((double)); + +#define lfptoa(_fpv, _ndec) mfptoa((_fpv)->l_ui, (_fpv)->l_uf, (_ndec)) +#define lfptoms(_fpv, _ndec) mfptoms((_fpv)->l_ui, (_fpv)->l_uf, (_ndec)) + +#define stoa(_sin) socktoa((_sin)) +#define stohost(_sin) socktohost((_sin)) + +#define ntoa(_sin) stoa(_sin) +#define ntohost(_sin) stohost(_sin) + +#define ufptoa(_fpv, _ndec) dofptoa((_fpv), 0, (_ndec), 0) +#define ufptoms(_fpv, _ndec) dofptoa((_fpv), 0, (_ndec), 1) +#define ulfptoa(_fpv, _ndec) dolfptoa((_fpv)->l_ui, (_fpv)->l_uf, 0, (_ndec), 0) +#define ulfptoms(_fpv, _ndec) dolfptoa((_fpv)->l_ui, (_fpv)->l_uf, 0, (_ndec), 1) +#define umfptoa(_fpi, _fpf, _ndec) dolfptoa((_fpi), (_fpf), 0, (_ndec), 0) + +#endif /* NTP_FP_H */ |