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