| 1 | /* numeric.c |
| 2 | * |
| 3 | * Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, |
| 4 | * 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others |
| 5 | * |
| 6 | * You may distribute under the terms of either the GNU General Public |
| 7 | * License or the Artistic License, as specified in the README file. |
| 8 | * |
| 9 | */ |
| 10 | |
| 11 | /* |
| 12 | * "That only makes eleven (plus one mislaid) and not fourteen, |
| 13 | * unless wizards count differently to other people." --Beorn |
| 14 | * |
| 15 | * [p.115 of _The Hobbit_: "Queer Lodgings"] |
| 16 | */ |
| 17 | |
| 18 | /* |
| 19 | =head1 Numeric functions |
| 20 | |
| 21 | =cut |
| 22 | |
| 23 | This file contains all the stuff needed by perl for manipulating numeric |
| 24 | values, including such things as replacements for the OS's atof() function |
| 25 | |
| 26 | */ |
| 27 | |
| 28 | #include "EXTERN.h" |
| 29 | #define PERL_IN_NUMERIC_C |
| 30 | #include "perl.h" |
| 31 | |
| 32 | U32 |
| 33 | Perl_cast_ulong(NV f) |
| 34 | { |
| 35 | if (f < 0.0) |
| 36 | return f < I32_MIN ? (U32) I32_MIN : (U32)(I32) f; |
| 37 | if (f < U32_MAX_P1) { |
| 38 | #if CASTFLAGS & 2 |
| 39 | if (f < U32_MAX_P1_HALF) |
| 40 | return (U32) f; |
| 41 | f -= U32_MAX_P1_HALF; |
| 42 | return ((U32) f) | (1 + (U32_MAX >> 1)); |
| 43 | #else |
| 44 | return (U32) f; |
| 45 | #endif |
| 46 | } |
| 47 | return f > 0 ? U32_MAX : 0 /* NaN */; |
| 48 | } |
| 49 | |
| 50 | I32 |
| 51 | Perl_cast_i32(NV f) |
| 52 | { |
| 53 | if (f < I32_MAX_P1) |
| 54 | return f < I32_MIN ? I32_MIN : (I32) f; |
| 55 | if (f < U32_MAX_P1) { |
| 56 | #if CASTFLAGS & 2 |
| 57 | if (f < U32_MAX_P1_HALF) |
| 58 | return (I32)(U32) f; |
| 59 | f -= U32_MAX_P1_HALF; |
| 60 | return (I32)(((U32) f) | (1 + (U32_MAX >> 1))); |
| 61 | #else |
| 62 | return (I32)(U32) f; |
| 63 | #endif |
| 64 | } |
| 65 | return f > 0 ? (I32)U32_MAX : 0 /* NaN */; |
| 66 | } |
| 67 | |
| 68 | IV |
| 69 | Perl_cast_iv(NV f) |
| 70 | { |
| 71 | if (f < IV_MAX_P1) |
| 72 | return f < IV_MIN ? IV_MIN : (IV) f; |
| 73 | if (f < UV_MAX_P1) { |
| 74 | #if CASTFLAGS & 2 |
| 75 | /* For future flexibility allowing for sizeof(UV) >= sizeof(IV) */ |
| 76 | if (f < UV_MAX_P1_HALF) |
| 77 | return (IV)(UV) f; |
| 78 | f -= UV_MAX_P1_HALF; |
| 79 | return (IV)(((UV) f) | (1 + (UV_MAX >> 1))); |
| 80 | #else |
| 81 | return (IV)(UV) f; |
| 82 | #endif |
| 83 | } |
| 84 | return f > 0 ? (IV)UV_MAX : 0 /* NaN */; |
| 85 | } |
| 86 | |
| 87 | UV |
| 88 | Perl_cast_uv(NV f) |
| 89 | { |
| 90 | if (f < 0.0) |
| 91 | return f < IV_MIN ? (UV) IV_MIN : (UV)(IV) f; |
| 92 | if (f < UV_MAX_P1) { |
| 93 | #if CASTFLAGS & 2 |
| 94 | if (f < UV_MAX_P1_HALF) |
| 95 | return (UV) f; |
| 96 | f -= UV_MAX_P1_HALF; |
| 97 | return ((UV) f) | (1 + (UV_MAX >> 1)); |
| 98 | #else |
| 99 | return (UV) f; |
| 100 | #endif |
| 101 | } |
| 102 | return f > 0 ? UV_MAX : 0 /* NaN */; |
| 103 | } |
| 104 | |
| 105 | /* |
| 106 | =for apidoc grok_bin |
| 107 | |
| 108 | converts a string representing a binary number to numeric form. |
| 109 | |
| 110 | On entry C<start> and C<*len> give the string to scan, C<*flags> gives |
| 111 | conversion flags, and C<result> should be C<NULL> or a pointer to an NV. |
| 112 | The scan stops at the end of the string, or the first invalid character. |
| 113 | Unless C<PERL_SCAN_SILENT_ILLDIGIT> is set in C<*flags>, encountering an |
| 114 | invalid character will also trigger a warning. |
| 115 | On return C<*len> is set to the length of the scanned string, |
| 116 | and C<*flags> gives output flags. |
| 117 | |
| 118 | If the value is <= C<UV_MAX> it is returned as a UV, the output flags are clear, |
| 119 | and nothing is written to C<*result>. If the value is > C<UV_MAX>, C<grok_bin> |
| 120 | returns C<UV_MAX>, sets C<PERL_SCAN_GREATER_THAN_UV_MAX> in the output flags, |
| 121 | and writes the value to C<*result> (or the value is discarded if C<result> |
| 122 | is NULL). |
| 123 | |
| 124 | The binary number may optionally be prefixed with C<"0b"> or C<"b"> unless |
| 125 | C<PERL_SCAN_DISALLOW_PREFIX> is set in C<*flags> on entry. If |
| 126 | C<PERL_SCAN_ALLOW_UNDERSCORES> is set in C<*flags> then the binary |
| 127 | number may use C<"_"> characters to separate digits. |
| 128 | |
| 129 | =cut |
| 130 | |
| 131 | Not documented yet because experimental is C<PERL_SCAN_SILENT_NON_PORTABLE |
| 132 | which suppresses any message for non-portable numbers that are still valid |
| 133 | on this platform. |
| 134 | */ |
| 135 | |
| 136 | UV |
| 137 | Perl_grok_bin(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result) |
| 138 | { |
| 139 | const char *s = start; |
| 140 | STRLEN len = *len_p; |
| 141 | UV value = 0; |
| 142 | NV value_nv = 0; |
| 143 | |
| 144 | const UV max_div_2 = UV_MAX / 2; |
| 145 | const bool allow_underscores = cBOOL(*flags & PERL_SCAN_ALLOW_UNDERSCORES); |
| 146 | bool overflowed = FALSE; |
| 147 | char bit; |
| 148 | |
| 149 | PERL_ARGS_ASSERT_GROK_BIN; |
| 150 | |
| 151 | if (!(*flags & PERL_SCAN_DISALLOW_PREFIX)) { |
| 152 | /* strip off leading b or 0b. |
| 153 | for compatibility silently suffer "b" and "0b" as valid binary |
| 154 | numbers. */ |
| 155 | if (len >= 1) { |
| 156 | if (isALPHA_FOLD_EQ(s[0], 'b')) { |
| 157 | s++; |
| 158 | len--; |
| 159 | } |
| 160 | else if (len >= 2 && s[0] == '0' && (isALPHA_FOLD_EQ(s[1], 'b'))) { |
| 161 | s+=2; |
| 162 | len-=2; |
| 163 | } |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | for (; len-- && (bit = *s); s++) { |
| 168 | if (bit == '0' || bit == '1') { |
| 169 | /* Write it in this wonky order with a goto to attempt to get the |
| 170 | compiler to make the common case integer-only loop pretty tight. |
| 171 | With gcc seems to be much straighter code than old scan_bin. */ |
| 172 | redo: |
| 173 | if (!overflowed) { |
| 174 | if (value <= max_div_2) { |
| 175 | value = (value << 1) | (bit - '0'); |
| 176 | continue; |
| 177 | } |
| 178 | /* Bah. We're just overflowed. */ |
| 179 | /* diag_listed_as: Integer overflow in %s number */ |
| 180 | Perl_ck_warner_d(aTHX_ packWARN(WARN_OVERFLOW), |
| 181 | "Integer overflow in binary number"); |
| 182 | overflowed = TRUE; |
| 183 | value_nv = (NV) value; |
| 184 | } |
| 185 | value_nv *= 2.0; |
| 186 | /* If an NV has not enough bits in its mantissa to |
| 187 | * represent a UV this summing of small low-order numbers |
| 188 | * is a waste of time (because the NV cannot preserve |
| 189 | * the low-order bits anyway): we could just remember when |
| 190 | * did we overflow and in the end just multiply value_nv by the |
| 191 | * right amount. */ |
| 192 | value_nv += (NV)(bit - '0'); |
| 193 | continue; |
| 194 | } |
| 195 | if (bit == '_' && len && allow_underscores && (bit = s[1]) |
| 196 | && (bit == '0' || bit == '1')) |
| 197 | { |
| 198 | --len; |
| 199 | ++s; |
| 200 | goto redo; |
| 201 | } |
| 202 | if (!(*flags & PERL_SCAN_SILENT_ILLDIGIT)) |
| 203 | Perl_ck_warner(aTHX_ packWARN(WARN_DIGIT), |
| 204 | "Illegal binary digit '%c' ignored", *s); |
| 205 | break; |
| 206 | } |
| 207 | |
| 208 | if ( ( overflowed && value_nv > 4294967295.0) |
| 209 | #if UVSIZE > 4 |
| 210 | || (!overflowed && value > 0xffffffff |
| 211 | && ! (*flags & PERL_SCAN_SILENT_NON_PORTABLE)) |
| 212 | #endif |
| 213 | ) { |
| 214 | Perl_ck_warner(aTHX_ packWARN(WARN_PORTABLE), |
| 215 | "Binary number > 0b11111111111111111111111111111111 non-portable"); |
| 216 | } |
| 217 | *len_p = s - start; |
| 218 | if (!overflowed) { |
| 219 | *flags = 0; |
| 220 | return value; |
| 221 | } |
| 222 | *flags = PERL_SCAN_GREATER_THAN_UV_MAX; |
| 223 | if (result) |
| 224 | *result = value_nv; |
| 225 | return UV_MAX; |
| 226 | } |
| 227 | |
| 228 | /* |
| 229 | =for apidoc grok_hex |
| 230 | |
| 231 | converts a string representing a hex number to numeric form. |
| 232 | |
| 233 | On entry C<start> and C<*len_p> give the string to scan, C<*flags> gives |
| 234 | conversion flags, and C<result> should be C<NULL> or a pointer to an NV. |
| 235 | The scan stops at the end of the string, or the first invalid character. |
| 236 | Unless C<PERL_SCAN_SILENT_ILLDIGIT> is set in C<*flags>, encountering an |
| 237 | invalid character will also trigger a warning. |
| 238 | On return C<*len> is set to the length of the scanned string, |
| 239 | and C<*flags> gives output flags. |
| 240 | |
| 241 | If the value is <= C<UV_MAX> it is returned as a UV, the output flags are clear, |
| 242 | and nothing is written to C<*result>. If the value is > C<UV_MAX>, C<grok_hex> |
| 243 | returns C<UV_MAX>, sets C<PERL_SCAN_GREATER_THAN_UV_MAX> in the output flags, |
| 244 | and writes the value to C<*result> (or the value is discarded if C<result> |
| 245 | is C<NULL>). |
| 246 | |
| 247 | The hex number may optionally be prefixed with C<"0x"> or C<"x"> unless |
| 248 | C<PERL_SCAN_DISALLOW_PREFIX> is set in C<*flags> on entry. If |
| 249 | C<PERL_SCAN_ALLOW_UNDERSCORES> is set in C<*flags> then the hex |
| 250 | number may use C<"_"> characters to separate digits. |
| 251 | |
| 252 | =cut |
| 253 | |
| 254 | Not documented yet because experimental is C<PERL_SCAN_SILENT_NON_PORTABLE |
| 255 | which suppresses any message for non-portable numbers, but which are valid |
| 256 | on this platform. |
| 257 | */ |
| 258 | |
| 259 | UV |
| 260 | Perl_grok_hex(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result) |
| 261 | { |
| 262 | const char *s = start; |
| 263 | STRLEN len = *len_p; |
| 264 | UV value = 0; |
| 265 | NV value_nv = 0; |
| 266 | const UV max_div_16 = UV_MAX / 16; |
| 267 | const bool allow_underscores = cBOOL(*flags & PERL_SCAN_ALLOW_UNDERSCORES); |
| 268 | bool overflowed = FALSE; |
| 269 | |
| 270 | PERL_ARGS_ASSERT_GROK_HEX; |
| 271 | |
| 272 | if (!(*flags & PERL_SCAN_DISALLOW_PREFIX)) { |
| 273 | /* strip off leading x or 0x. |
| 274 | for compatibility silently suffer "x" and "0x" as valid hex numbers. |
| 275 | */ |
| 276 | if (len >= 1) { |
| 277 | if (isALPHA_FOLD_EQ(s[0], 'x')) { |
| 278 | s++; |
| 279 | len--; |
| 280 | } |
| 281 | else if (len >= 2 && s[0] == '0' && (isALPHA_FOLD_EQ(s[1], 'x'))) { |
| 282 | s+=2; |
| 283 | len-=2; |
| 284 | } |
| 285 | } |
| 286 | } |
| 287 | |
| 288 | for (; len-- && *s; s++) { |
| 289 | if (isXDIGIT(*s)) { |
| 290 | /* Write it in this wonky order with a goto to attempt to get the |
| 291 | compiler to make the common case integer-only loop pretty tight. |
| 292 | With gcc seems to be much straighter code than old scan_hex. */ |
| 293 | redo: |
| 294 | if (!overflowed) { |
| 295 | if (value <= max_div_16) { |
| 296 | value = (value << 4) | XDIGIT_VALUE(*s); |
| 297 | continue; |
| 298 | } |
| 299 | /* Bah. We're just overflowed. */ |
| 300 | /* diag_listed_as: Integer overflow in %s number */ |
| 301 | Perl_ck_warner_d(aTHX_ packWARN(WARN_OVERFLOW), |
| 302 | "Integer overflow in hexadecimal number"); |
| 303 | overflowed = TRUE; |
| 304 | value_nv = (NV) value; |
| 305 | } |
| 306 | value_nv *= 16.0; |
| 307 | /* If an NV has not enough bits in its mantissa to |
| 308 | * represent a UV this summing of small low-order numbers |
| 309 | * is a waste of time (because the NV cannot preserve |
| 310 | * the low-order bits anyway): we could just remember when |
| 311 | * did we overflow and in the end just multiply value_nv by the |
| 312 | * right amount of 16-tuples. */ |
| 313 | value_nv += (NV) XDIGIT_VALUE(*s); |
| 314 | continue; |
| 315 | } |
| 316 | if (*s == '_' && len && allow_underscores && s[1] |
| 317 | && isXDIGIT(s[1])) |
| 318 | { |
| 319 | --len; |
| 320 | ++s; |
| 321 | goto redo; |
| 322 | } |
| 323 | if (!(*flags & PERL_SCAN_SILENT_ILLDIGIT)) |
| 324 | Perl_ck_warner(aTHX_ packWARN(WARN_DIGIT), |
| 325 | "Illegal hexadecimal digit '%c' ignored", *s); |
| 326 | break; |
| 327 | } |
| 328 | |
| 329 | if ( ( overflowed && value_nv > 4294967295.0) |
| 330 | #if UVSIZE > 4 |
| 331 | || (!overflowed && value > 0xffffffff |
| 332 | && ! (*flags & PERL_SCAN_SILENT_NON_PORTABLE)) |
| 333 | #endif |
| 334 | ) { |
| 335 | Perl_ck_warner(aTHX_ packWARN(WARN_PORTABLE), |
| 336 | "Hexadecimal number > 0xffffffff non-portable"); |
| 337 | } |
| 338 | *len_p = s - start; |
| 339 | if (!overflowed) { |
| 340 | *flags = 0; |
| 341 | return value; |
| 342 | } |
| 343 | *flags = PERL_SCAN_GREATER_THAN_UV_MAX; |
| 344 | if (result) |
| 345 | *result = value_nv; |
| 346 | return UV_MAX; |
| 347 | } |
| 348 | |
| 349 | /* |
| 350 | =for apidoc grok_oct |
| 351 | |
| 352 | converts a string representing an octal number to numeric form. |
| 353 | |
| 354 | On entry C<start> and C<*len> give the string to scan, C<*flags> gives |
| 355 | conversion flags, and C<result> should be C<NULL> or a pointer to an NV. |
| 356 | The scan stops at the end of the string, or the first invalid character. |
| 357 | Unless C<PERL_SCAN_SILENT_ILLDIGIT> is set in C<*flags>, encountering an |
| 358 | 8 or 9 will also trigger a warning. |
| 359 | On return C<*len> is set to the length of the scanned string, |
| 360 | and C<*flags> gives output flags. |
| 361 | |
| 362 | If the value is <= C<UV_MAX> it is returned as a UV, the output flags are clear, |
| 363 | and nothing is written to C<*result>. If the value is > C<UV_MAX>, C<grok_oct> |
| 364 | returns C<UV_MAX>, sets C<PERL_SCAN_GREATER_THAN_UV_MAX> in the output flags, |
| 365 | and writes the value to C<*result> (or the value is discarded if C<result> |
| 366 | is C<NULL>). |
| 367 | |
| 368 | If C<PERL_SCAN_ALLOW_UNDERSCORES> is set in C<*flags> then the octal |
| 369 | number may use C<"_"> characters to separate digits. |
| 370 | |
| 371 | =cut |
| 372 | |
| 373 | Not documented yet because experimental is C<PERL_SCAN_SILENT_NON_PORTABLE> |
| 374 | which suppresses any message for non-portable numbers, but which are valid |
| 375 | on this platform. |
| 376 | */ |
| 377 | |
| 378 | UV |
| 379 | Perl_grok_oct(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result) |
| 380 | { |
| 381 | const char *s = start; |
| 382 | STRLEN len = *len_p; |
| 383 | UV value = 0; |
| 384 | NV value_nv = 0; |
| 385 | const UV max_div_8 = UV_MAX / 8; |
| 386 | const bool allow_underscores = cBOOL(*flags & PERL_SCAN_ALLOW_UNDERSCORES); |
| 387 | bool overflowed = FALSE; |
| 388 | |
| 389 | PERL_ARGS_ASSERT_GROK_OCT; |
| 390 | |
| 391 | for (; len-- && *s; s++) { |
| 392 | if (isOCTAL(*s)) { |
| 393 | /* Write it in this wonky order with a goto to attempt to get the |
| 394 | compiler to make the common case integer-only loop pretty tight. |
| 395 | */ |
| 396 | redo: |
| 397 | if (!overflowed) { |
| 398 | if (value <= max_div_8) { |
| 399 | value = (value << 3) | OCTAL_VALUE(*s); |
| 400 | continue; |
| 401 | } |
| 402 | /* Bah. We're just overflowed. */ |
| 403 | /* diag_listed_as: Integer overflow in %s number */ |
| 404 | Perl_ck_warner_d(aTHX_ packWARN(WARN_OVERFLOW), |
| 405 | "Integer overflow in octal number"); |
| 406 | overflowed = TRUE; |
| 407 | value_nv = (NV) value; |
| 408 | } |
| 409 | value_nv *= 8.0; |
| 410 | /* If an NV has not enough bits in its mantissa to |
| 411 | * represent a UV this summing of small low-order numbers |
| 412 | * is a waste of time (because the NV cannot preserve |
| 413 | * the low-order bits anyway): we could just remember when |
| 414 | * did we overflow and in the end just multiply value_nv by the |
| 415 | * right amount of 8-tuples. */ |
| 416 | value_nv += (NV) OCTAL_VALUE(*s); |
| 417 | continue; |
| 418 | } |
| 419 | if (*s == '_' && len && allow_underscores && isOCTAL(s[1])) { |
| 420 | --len; |
| 421 | ++s; |
| 422 | goto redo; |
| 423 | } |
| 424 | /* Allow \octal to work the DWIM way (that is, stop scanning |
| 425 | * as soon as non-octal characters are seen, complain only if |
| 426 | * someone seems to want to use the digits eight and nine. Since we |
| 427 | * know it is not octal, then if isDIGIT, must be an 8 or 9). */ |
| 428 | if (isDIGIT(*s)) { |
| 429 | if (!(*flags & PERL_SCAN_SILENT_ILLDIGIT)) |
| 430 | Perl_ck_warner(aTHX_ packWARN(WARN_DIGIT), |
| 431 | "Illegal octal digit '%c' ignored", *s); |
| 432 | } |
| 433 | break; |
| 434 | } |
| 435 | |
| 436 | if ( ( overflowed && value_nv > 4294967295.0) |
| 437 | #if UVSIZE > 4 |
| 438 | || (!overflowed && value > 0xffffffff |
| 439 | && ! (*flags & PERL_SCAN_SILENT_NON_PORTABLE)) |
| 440 | #endif |
| 441 | ) { |
| 442 | Perl_ck_warner(aTHX_ packWARN(WARN_PORTABLE), |
| 443 | "Octal number > 037777777777 non-portable"); |
| 444 | } |
| 445 | *len_p = s - start; |
| 446 | if (!overflowed) { |
| 447 | *flags = 0; |
| 448 | return value; |
| 449 | } |
| 450 | *flags = PERL_SCAN_GREATER_THAN_UV_MAX; |
| 451 | if (result) |
| 452 | *result = value_nv; |
| 453 | return UV_MAX; |
| 454 | } |
| 455 | |
| 456 | /* |
| 457 | =for apidoc scan_bin |
| 458 | |
| 459 | For backwards compatibility. Use C<grok_bin> instead. |
| 460 | |
| 461 | =for apidoc scan_hex |
| 462 | |
| 463 | For backwards compatibility. Use C<grok_hex> instead. |
| 464 | |
| 465 | =for apidoc scan_oct |
| 466 | |
| 467 | For backwards compatibility. Use C<grok_oct> instead. |
| 468 | |
| 469 | =cut |
| 470 | */ |
| 471 | |
| 472 | NV |
| 473 | Perl_scan_bin(pTHX_ const char *start, STRLEN len, STRLEN *retlen) |
| 474 | { |
| 475 | NV rnv; |
| 476 | I32 flags = *retlen ? PERL_SCAN_ALLOW_UNDERSCORES : 0; |
| 477 | const UV ruv = grok_bin (start, &len, &flags, &rnv); |
| 478 | |
| 479 | PERL_ARGS_ASSERT_SCAN_BIN; |
| 480 | |
| 481 | *retlen = len; |
| 482 | return (flags & PERL_SCAN_GREATER_THAN_UV_MAX) ? rnv : (NV)ruv; |
| 483 | } |
| 484 | |
| 485 | NV |
| 486 | Perl_scan_oct(pTHX_ const char *start, STRLEN len, STRLEN *retlen) |
| 487 | { |
| 488 | NV rnv; |
| 489 | I32 flags = *retlen ? PERL_SCAN_ALLOW_UNDERSCORES : 0; |
| 490 | const UV ruv = grok_oct (start, &len, &flags, &rnv); |
| 491 | |
| 492 | PERL_ARGS_ASSERT_SCAN_OCT; |
| 493 | |
| 494 | *retlen = len; |
| 495 | return (flags & PERL_SCAN_GREATER_THAN_UV_MAX) ? rnv : (NV)ruv; |
| 496 | } |
| 497 | |
| 498 | NV |
| 499 | Perl_scan_hex(pTHX_ const char *start, STRLEN len, STRLEN *retlen) |
| 500 | { |
| 501 | NV rnv; |
| 502 | I32 flags = *retlen ? PERL_SCAN_ALLOW_UNDERSCORES : 0; |
| 503 | const UV ruv = grok_hex (start, &len, &flags, &rnv); |
| 504 | |
| 505 | PERL_ARGS_ASSERT_SCAN_HEX; |
| 506 | |
| 507 | *retlen = len; |
| 508 | return (flags & PERL_SCAN_GREATER_THAN_UV_MAX) ? rnv : (NV)ruv; |
| 509 | } |
| 510 | |
| 511 | /* |
| 512 | =for apidoc grok_numeric_radix |
| 513 | |
| 514 | Scan and skip for a numeric decimal separator (radix). |
| 515 | |
| 516 | =cut |
| 517 | */ |
| 518 | bool |
| 519 | Perl_grok_numeric_radix(pTHX_ const char **sp, const char *send) |
| 520 | { |
| 521 | #ifdef USE_LOCALE_NUMERIC |
| 522 | PERL_ARGS_ASSERT_GROK_NUMERIC_RADIX; |
| 523 | |
| 524 | if (IN_LC(LC_NUMERIC)) { |
| 525 | DECLARATION_FOR_LC_NUMERIC_MANIPULATION; |
| 526 | STORE_LC_NUMERIC_SET_TO_NEEDED(); |
| 527 | if (PL_numeric_radix_sv) { |
| 528 | STRLEN len; |
| 529 | const char * const radix = SvPV(PL_numeric_radix_sv, len); |
| 530 | if (*sp + len <= send && memEQ(*sp, radix, len)) { |
| 531 | *sp += len; |
| 532 | RESTORE_LC_NUMERIC(); |
| 533 | return TRUE; |
| 534 | } |
| 535 | } |
| 536 | RESTORE_LC_NUMERIC(); |
| 537 | } |
| 538 | /* always try "." if numeric radix didn't match because |
| 539 | * we may have data from different locales mixed */ |
| 540 | #endif |
| 541 | |
| 542 | PERL_ARGS_ASSERT_GROK_NUMERIC_RADIX; |
| 543 | |
| 544 | if (*sp < send && **sp == '.') { |
| 545 | ++*sp; |
| 546 | return TRUE; |
| 547 | } |
| 548 | return FALSE; |
| 549 | } |
| 550 | |
| 551 | /* |
| 552 | =for apidoc grok_infnan |
| 553 | |
| 554 | Helper for C<grok_number()>, accepts various ways of spelling "infinity" |
| 555 | or "not a number", and returns one of the following flag combinations: |
| 556 | |
| 557 | IS_NUMBER_INFINITE |
| 558 | IS_NUMBER_NAN |
| 559 | IS_NUMBER_INFINITE | IS_NUMBER_NEG |
| 560 | IS_NUMBER_NAN | IS_NUMBER_NEG |
| 561 | 0 |
| 562 | |
| 563 | possibly |-ed with C<IS_NUMBER_TRAILING>. |
| 564 | |
| 565 | If an infinity or a not-a-number is recognized, C<*sp> will point to |
| 566 | one byte past the end of the recognized string. If the recognition fails, |
| 567 | zero is returned, and C<*sp> will not move. |
| 568 | |
| 569 | =cut |
| 570 | */ |
| 571 | |
| 572 | int |
| 573 | Perl_grok_infnan(pTHX_ const char** sp, const char* send) |
| 574 | { |
| 575 | const char* s = *sp; |
| 576 | int flags = 0; |
| 577 | bool odh = FALSE; /* one-dot-hash: 1.#INF */ |
| 578 | |
| 579 | PERL_ARGS_ASSERT_GROK_INFNAN; |
| 580 | |
| 581 | if (*s == '+') { |
| 582 | s++; if (s == send) return 0; |
| 583 | } |
| 584 | else if (*s == '-') { |
| 585 | flags |= IS_NUMBER_NEG; /* Yes, -NaN happens. Incorrect but happens. */ |
| 586 | s++; if (s == send) return 0; |
| 587 | } |
| 588 | |
| 589 | if (*s == '1') { |
| 590 | /* Visual C: 1.#SNAN, -1.#QNAN, 1#INF, 1.#IND (maybe also 1.#NAN) |
| 591 | * Let's keep the dot optional. */ |
| 592 | s++; if (s == send) return 0; |
| 593 | if (*s == '.') { |
| 594 | s++; if (s == send) return 0; |
| 595 | } |
| 596 | if (*s == '#') { |
| 597 | s++; if (s == send) return 0; |
| 598 | } else |
| 599 | return 0; |
| 600 | odh = TRUE; |
| 601 | } |
| 602 | |
| 603 | if (isALPHA_FOLD_EQ(*s, 'I')) { |
| 604 | /* INF or IND (1.#IND is "indeterminate", a certain type of NAN) */ |
| 605 | |
| 606 | s++; if (s == send || isALPHA_FOLD_NE(*s, 'N')) return 0; |
| 607 | s++; if (s == send) return 0; |
| 608 | if (isALPHA_FOLD_EQ(*s, 'F')) { |
| 609 | s++; |
| 610 | if (s < send && (isALPHA_FOLD_EQ(*s, 'I'))) { |
| 611 | int fail = |
| 612 | flags | IS_NUMBER_INFINITY | IS_NUMBER_NOT_INT | IS_NUMBER_TRAILING; |
| 613 | s++; if (s == send || isALPHA_FOLD_NE(*s, 'N')) return fail; |
| 614 | s++; if (s == send || isALPHA_FOLD_NE(*s, 'I')) return fail; |
| 615 | s++; if (s == send || isALPHA_FOLD_NE(*s, 'T')) return fail; |
| 616 | s++; if (s == send || isALPHA_FOLD_NE(*s, 'Y')) return fail; |
| 617 | s++; |
| 618 | } else if (odh) { |
| 619 | while (*s == '0') { /* 1.#INF00 */ |
| 620 | s++; |
| 621 | } |
| 622 | } |
| 623 | while (s < send && isSPACE(*s)) |
| 624 | s++; |
| 625 | if (s < send && *s) { |
| 626 | flags |= IS_NUMBER_TRAILING; |
| 627 | } |
| 628 | flags |= IS_NUMBER_INFINITY | IS_NUMBER_NOT_INT; |
| 629 | } |
| 630 | else if (isALPHA_FOLD_EQ(*s, 'D') && odh) { /* 1.#IND */ |
| 631 | s++; |
| 632 | flags |= IS_NUMBER_NAN | IS_NUMBER_NOT_INT; |
| 633 | while (*s == '0') { /* 1.#IND00 */ |
| 634 | s++; |
| 635 | } |
| 636 | if (*s) { |
| 637 | flags |= IS_NUMBER_TRAILING; |
| 638 | } |
| 639 | } else |
| 640 | return 0; |
| 641 | } |
| 642 | else { |
| 643 | /* Maybe NAN of some sort */ |
| 644 | |
| 645 | if (isALPHA_FOLD_EQ(*s, 'S') || isALPHA_FOLD_EQ(*s, 'Q')) { |
| 646 | /* snan, qNaN */ |
| 647 | /* XXX do something with the snan/qnan difference */ |
| 648 | s++; if (s == send) return 0; |
| 649 | } |
| 650 | |
| 651 | if (isALPHA_FOLD_EQ(*s, 'N')) { |
| 652 | s++; if (s == send || isALPHA_FOLD_NE(*s, 'A')) return 0; |
| 653 | s++; if (s == send || isALPHA_FOLD_NE(*s, 'N')) return 0; |
| 654 | s++; |
| 655 | |
| 656 | flags |= IS_NUMBER_NAN | IS_NUMBER_NOT_INT; |
| 657 | |
| 658 | /* NaN can be followed by various stuff (NaNQ, NaNS), but |
| 659 | * there are also multiple different NaN values, and some |
| 660 | * implementations output the "payload" values, |
| 661 | * e.g. NaN123, NAN(abc), while some legacy implementations |
| 662 | * have weird stuff like NaN%. */ |
| 663 | if (isALPHA_FOLD_EQ(*s, 'q') || |
| 664 | isALPHA_FOLD_EQ(*s, 's')) { |
| 665 | /* "nanq" or "nans" are ok, though generating |
| 666 | * these portably is tricky. */ |
| 667 | s++; |
| 668 | } |
| 669 | if (*s == '(') { |
| 670 | /* C99 style "nan(123)" or Perlish equivalent "nan($uv)". */ |
| 671 | const char *t; |
| 672 | s++; |
| 673 | if (s == send) { |
| 674 | return flags | IS_NUMBER_TRAILING; |
| 675 | } |
| 676 | t = s + 1; |
| 677 | while (t < send && *t && *t != ')') { |
| 678 | t++; |
| 679 | } |
| 680 | if (t == send) { |
| 681 | return flags | IS_NUMBER_TRAILING; |
| 682 | } |
| 683 | if (*t == ')') { |
| 684 | int nantype; |
| 685 | UV nanval; |
| 686 | if (s[0] == '0' && s + 2 < t && |
| 687 | isALPHA_FOLD_EQ(s[1], 'x') && |
| 688 | isXDIGIT(s[2])) { |
| 689 | STRLEN len = t - s; |
| 690 | I32 flags = PERL_SCAN_ALLOW_UNDERSCORES; |
| 691 | nanval = grok_hex(s, &len, &flags, NULL); |
| 692 | if ((flags & PERL_SCAN_GREATER_THAN_UV_MAX)) { |
| 693 | nantype = 0; |
| 694 | } else { |
| 695 | nantype = IS_NUMBER_IN_UV; |
| 696 | } |
| 697 | s += len; |
| 698 | } else if (s[0] == '0' && s + 2 < t && |
| 699 | isALPHA_FOLD_EQ(s[1], 'b') && |
| 700 | (s[2] == '0' || s[2] == '1')) { |
| 701 | STRLEN len = t - s; |
| 702 | I32 flags = PERL_SCAN_ALLOW_UNDERSCORES; |
| 703 | nanval = grok_bin(s, &len, &flags, NULL); |
| 704 | if ((flags & PERL_SCAN_GREATER_THAN_UV_MAX)) { |
| 705 | nantype = 0; |
| 706 | } else { |
| 707 | nantype = IS_NUMBER_IN_UV; |
| 708 | } |
| 709 | s += len; |
| 710 | } else { |
| 711 | const char *u; |
| 712 | nantype = |
| 713 | grok_number_flags(s, t - s, &nanval, |
| 714 | PERL_SCAN_TRAILING | |
| 715 | PERL_SCAN_ALLOW_UNDERSCORES); |
| 716 | /* Unfortunately grok_number_flags() doesn't |
| 717 | * tell how far we got and the ')' will always |
| 718 | * be "trailing", so we need to double-check |
| 719 | * whether we had something dubious. */ |
| 720 | for (u = s; u < t; u++) { |
| 721 | if (!isDIGIT(*u)) { |
| 722 | flags |= IS_NUMBER_TRAILING; |
| 723 | break; |
| 724 | } |
| 725 | } |
| 726 | s = u; |
| 727 | } |
| 728 | |
| 729 | /* XXX Doesn't do octal: nan("0123"). |
| 730 | * Probably not a big loss. */ |
| 731 | |
| 732 | if ((nantype & IS_NUMBER_NOT_INT) || |
| 733 | !(nantype && IS_NUMBER_IN_UV)) { |
| 734 | /* XXX the nanval is currently unused, that is, |
| 735 | * not inserted as the NaN payload of the NV. |
| 736 | * But the above code already parses the C99 |
| 737 | * nan(...) format. See below, and see also |
| 738 | * the nan() in POSIX.xs. |
| 739 | * |
| 740 | * Certain configuration combinations where |
| 741 | * NVSIZE is greater than UVSIZE mean that |
| 742 | * a single UV cannot contain all the possible |
| 743 | * NaN payload bits. There would need to be |
| 744 | * some more generic syntax than "nan($uv)". |
| 745 | * |
| 746 | * Issues to keep in mind: |
| 747 | * |
| 748 | * (1) In most common cases there would |
| 749 | * not be an integral number of bytes that |
| 750 | * could be set, only a certain number of bits. |
| 751 | * For example for the common case of |
| 752 | * NVSIZE == UVSIZE == 8 there is room for 52 |
| 753 | * bits in the payload, but the most significant |
| 754 | * bit is commonly reserved for the |
| 755 | * signaling/quiet bit, leaving 51 bits. |
| 756 | * Furthermore, the C99 nan() is supposed |
| 757 | * to generate quiet NaNs, so it is doubtful |
| 758 | * whether it should be able to generate |
| 759 | * signaling NaNs. For the x86 80-bit doubles |
| 760 | * (if building a long double Perl) there would |
| 761 | * be 62 bits (s/q bit being the 63rd). |
| 762 | * |
| 763 | * (2) Endianness of the payload bits. If the |
| 764 | * payload is specified as an UV, the low-order |
| 765 | * bits of the UV are naturally little-endianed |
| 766 | * (rightmost) bits of the payload. The endianness |
| 767 | * of UVs and NVs can be different. */ |
| 768 | return 0; |
| 769 | } |
| 770 | if (s < t) { |
| 771 | flags |= IS_NUMBER_TRAILING; |
| 772 | } |
| 773 | } else { |
| 774 | /* Looked like nan(...), but no close paren. */ |
| 775 | flags |= IS_NUMBER_TRAILING; |
| 776 | } |
| 777 | } else { |
| 778 | while (s < send && isSPACE(*s)) |
| 779 | s++; |
| 780 | if (s < send && *s) { |
| 781 | /* Note that we here implicitly accept (parse as |
| 782 | * "nan", but with warnings) also any other weird |
| 783 | * trailing stuff for "nan". In the above we just |
| 784 | * check that if we got the C99-style "nan(...)", |
| 785 | * the "..." looks sane. |
| 786 | * If in future we accept more ways of specifying |
| 787 | * the nan payload, the accepting would happen around |
| 788 | * here. */ |
| 789 | flags |= IS_NUMBER_TRAILING; |
| 790 | } |
| 791 | } |
| 792 | s = send; |
| 793 | } |
| 794 | else |
| 795 | return 0; |
| 796 | } |
| 797 | |
| 798 | while (s < send && isSPACE(*s)) |
| 799 | s++; |
| 800 | |
| 801 | *sp = s; |
| 802 | return flags; |
| 803 | } |
| 804 | |
| 805 | /* |
| 806 | =for apidoc grok_number_flags |
| 807 | |
| 808 | Recognise (or not) a number. The type of the number is returned |
| 809 | (0 if unrecognised), otherwise it is a bit-ORed combination of |
| 810 | C<IS_NUMBER_IN_UV>, C<IS_NUMBER_GREATER_THAN_UV_MAX>, C<IS_NUMBER_NOT_INT>, |
| 811 | C<IS_NUMBER_NEG>, C<IS_NUMBER_INFINITY>, C<IS_NUMBER_NAN> (defined in perl.h). |
| 812 | |
| 813 | If the value of the number can fit in a UV, it is returned in C<*valuep>. |
| 814 | C<IS_NUMBER_IN_UV> will be set to indicate that C<*valuep> is valid, C<IS_NUMBER_IN_UV> |
| 815 | will never be set unless C<*valuep> is valid, but C<*valuep> may have been assigned |
| 816 | to during processing even though C<IS_NUMBER_IN_UV> is not set on return. |
| 817 | If C<valuep> is C<NULL>, C<IS_NUMBER_IN_UV> will be set for the same cases as when |
| 818 | C<valuep> is non-C<NULL>, but no actual assignment (or SEGV) will occur. |
| 819 | |
| 820 | C<IS_NUMBER_NOT_INT> will be set with C<IS_NUMBER_IN_UV> if trailing decimals were |
| 821 | seen (in which case C<*valuep> gives the true value truncated to an integer), and |
| 822 | C<IS_NUMBER_NEG> if the number is negative (in which case C<*valuep> holds the |
| 823 | absolute value). C<IS_NUMBER_IN_UV> is not set if e notation was used or the |
| 824 | number is larger than a UV. |
| 825 | |
| 826 | C<flags> allows only C<PERL_SCAN_TRAILING>, which allows for trailing |
| 827 | non-numeric text on an otherwise successful I<grok>, setting |
| 828 | C<IS_NUMBER_TRAILING> on the result. |
| 829 | |
| 830 | =for apidoc grok_number |
| 831 | |
| 832 | Identical to C<grok_number_flags()> with C<flags> set to zero. |
| 833 | |
| 834 | =cut |
| 835 | */ |
| 836 | int |
| 837 | Perl_grok_number(pTHX_ const char *pv, STRLEN len, UV *valuep) |
| 838 | { |
| 839 | PERL_ARGS_ASSERT_GROK_NUMBER; |
| 840 | |
| 841 | return grok_number_flags(pv, len, valuep, 0); |
| 842 | } |
| 843 | |
| 844 | static const UV uv_max_div_10 = UV_MAX / 10; |
| 845 | static const U8 uv_max_mod_10 = UV_MAX % 10; |
| 846 | |
| 847 | int |
| 848 | Perl_grok_number_flags(pTHX_ const char *pv, STRLEN len, UV *valuep, U32 flags) |
| 849 | { |
| 850 | const char *s = pv; |
| 851 | const char * const send = pv + len; |
| 852 | const char *d; |
| 853 | int numtype = 0; |
| 854 | |
| 855 | PERL_ARGS_ASSERT_GROK_NUMBER_FLAGS; |
| 856 | |
| 857 | while (s < send && isSPACE(*s)) |
| 858 | s++; |
| 859 | if (s == send) { |
| 860 | return 0; |
| 861 | } else if (*s == '-') { |
| 862 | s++; |
| 863 | numtype = IS_NUMBER_NEG; |
| 864 | } |
| 865 | else if (*s == '+') |
| 866 | s++; |
| 867 | |
| 868 | if (s == send) |
| 869 | return 0; |
| 870 | |
| 871 | /* The first digit (after optional sign): note that might |
| 872 | * also point to "infinity" or "nan", or "1.#INF". */ |
| 873 | d = s; |
| 874 | |
| 875 | /* next must be digit or the radix separator or beginning of infinity/nan */ |
| 876 | if (isDIGIT(*s)) { |
| 877 | /* UVs are at least 32 bits, so the first 9 decimal digits cannot |
| 878 | overflow. */ |
| 879 | UV value = *s - '0'; |
| 880 | /* This construction seems to be more optimiser friendly. |
| 881 | (without it gcc does the isDIGIT test and the *s - '0' separately) |
| 882 | With it gcc on arm is managing 6 instructions (6 cycles) per digit. |
| 883 | In theory the optimiser could deduce how far to unroll the loop |
| 884 | before checking for overflow. */ |
| 885 | if (++s < send) { |
| 886 | int digit = *s - '0'; |
| 887 | if (digit >= 0 && digit <= 9) { |
| 888 | value = value * 10 + digit; |
| 889 | if (++s < send) { |
| 890 | digit = *s - '0'; |
| 891 | if (digit >= 0 && digit <= 9) { |
| 892 | value = value * 10 + digit; |
| 893 | if (++s < send) { |
| 894 | digit = *s - '0'; |
| 895 | if (digit >= 0 && digit <= 9) { |
| 896 | value = value * 10 + digit; |
| 897 | if (++s < send) { |
| 898 | digit = *s - '0'; |
| 899 | if (digit >= 0 && digit <= 9) { |
| 900 | value = value * 10 + digit; |
| 901 | if (++s < send) { |
| 902 | digit = *s - '0'; |
| 903 | if (digit >= 0 && digit <= 9) { |
| 904 | value = value * 10 + digit; |
| 905 | if (++s < send) { |
| 906 | digit = *s - '0'; |
| 907 | if (digit >= 0 && digit <= 9) { |
| 908 | value = value * 10 + digit; |
| 909 | if (++s < send) { |
| 910 | digit = *s - '0'; |
| 911 | if (digit >= 0 && digit <= 9) { |
| 912 | value = value * 10 + digit; |
| 913 | if (++s < send) { |
| 914 | digit = *s - '0'; |
| 915 | if (digit >= 0 && digit <= 9) { |
| 916 | value = value * 10 + digit; |
| 917 | if (++s < send) { |
| 918 | /* Now got 9 digits, so need to check |
| 919 | each time for overflow. */ |
| 920 | digit = *s - '0'; |
| 921 | while (digit >= 0 && digit <= 9 |
| 922 | && (value < uv_max_div_10 |
| 923 | || (value == uv_max_div_10 |
| 924 | && digit <= uv_max_mod_10))) { |
| 925 | value = value * 10 + digit; |
| 926 | if (++s < send) |
| 927 | digit = *s - '0'; |
| 928 | else |
| 929 | break; |
| 930 | } |
| 931 | if (digit >= 0 && digit <= 9 |
| 932 | && (s < send)) { |
| 933 | /* value overflowed. |
| 934 | skip the remaining digits, don't |
| 935 | worry about setting *valuep. */ |
| 936 | do { |
| 937 | s++; |
| 938 | } while (s < send && isDIGIT(*s)); |
| 939 | numtype |= |
| 940 | IS_NUMBER_GREATER_THAN_UV_MAX; |
| 941 | goto skip_value; |
| 942 | } |
| 943 | } |
| 944 | } |
| 945 | } |
| 946 | } |
| 947 | } |
| 948 | } |
| 949 | } |
| 950 | } |
| 951 | } |
| 952 | } |
| 953 | } |
| 954 | } |
| 955 | } |
| 956 | } |
| 957 | } |
| 958 | } |
| 959 | } |
| 960 | numtype |= IS_NUMBER_IN_UV; |
| 961 | if (valuep) |
| 962 | *valuep = value; |
| 963 | |
| 964 | skip_value: |
| 965 | if (GROK_NUMERIC_RADIX(&s, send)) { |
| 966 | numtype |= IS_NUMBER_NOT_INT; |
| 967 | while (s < send && isDIGIT(*s)) /* optional digits after the radix */ |
| 968 | s++; |
| 969 | } |
| 970 | } |
| 971 | else if (GROK_NUMERIC_RADIX(&s, send)) { |
| 972 | numtype |= IS_NUMBER_NOT_INT | IS_NUMBER_IN_UV; /* valuep assigned below */ |
| 973 | /* no digits before the radix means we need digits after it */ |
| 974 | if (s < send && isDIGIT(*s)) { |
| 975 | do { |
| 976 | s++; |
| 977 | } while (s < send && isDIGIT(*s)); |
| 978 | if (valuep) { |
| 979 | /* integer approximation is valid - it's 0. */ |
| 980 | *valuep = 0; |
| 981 | } |
| 982 | } |
| 983 | else |
| 984 | return 0; |
| 985 | } |
| 986 | |
| 987 | if (s > d && s < send) { |
| 988 | /* we can have an optional exponent part */ |
| 989 | if (isALPHA_FOLD_EQ(*s, 'e')) { |
| 990 | s++; |
| 991 | if (s < send && (*s == '-' || *s == '+')) |
| 992 | s++; |
| 993 | if (s < send && isDIGIT(*s)) { |
| 994 | do { |
| 995 | s++; |
| 996 | } while (s < send && isDIGIT(*s)); |
| 997 | } |
| 998 | else if (flags & PERL_SCAN_TRAILING) |
| 999 | return numtype | IS_NUMBER_TRAILING; |
| 1000 | else |
| 1001 | return 0; |
| 1002 | |
| 1003 | /* The only flag we keep is sign. Blow away any "it's UV" */ |
| 1004 | numtype &= IS_NUMBER_NEG; |
| 1005 | numtype |= IS_NUMBER_NOT_INT; |
| 1006 | } |
| 1007 | } |
| 1008 | while (s < send && isSPACE(*s)) |
| 1009 | s++; |
| 1010 | if (s >= send) |
| 1011 | return numtype; |
| 1012 | if (len == 10 && memEQ(pv, "0 but true", 10)) { |
| 1013 | if (valuep) |
| 1014 | *valuep = 0; |
| 1015 | return IS_NUMBER_IN_UV; |
| 1016 | } |
| 1017 | /* We could be e.g. at "Inf" or "NaN", or at the "#" of "1.#INF". */ |
| 1018 | if ((s + 2 < send) && strchr("inqs#", toFOLD(*s))) { |
| 1019 | /* Really detect inf/nan. Start at d, not s, since the above |
| 1020 | * code might have already consumed the "1." or "1". */ |
| 1021 | int infnan = Perl_grok_infnan(aTHX_ &d, send); |
| 1022 | if ((infnan & IS_NUMBER_INFINITY)) { |
| 1023 | return (numtype | infnan); /* Keep sign for infinity. */ |
| 1024 | } |
| 1025 | else if ((infnan & IS_NUMBER_NAN)) { |
| 1026 | return (numtype | infnan) & ~IS_NUMBER_NEG; /* Clear sign for nan. */ |
| 1027 | } |
| 1028 | } |
| 1029 | else if (flags & PERL_SCAN_TRAILING) { |
| 1030 | return numtype | IS_NUMBER_TRAILING; |
| 1031 | } |
| 1032 | |
| 1033 | return 0; |
| 1034 | } |
| 1035 | |
| 1036 | /* |
| 1037 | grok_atoUV |
| 1038 | |
| 1039 | grok_atoUV parses a C-style zero-byte terminated string, looking for |
| 1040 | a decimal unsigned integer. |
| 1041 | |
| 1042 | Returns the unsigned integer, if a valid value can be parsed |
| 1043 | from the beginning of the string. |
| 1044 | |
| 1045 | Accepts only the decimal digits '0'..'9'. |
| 1046 | |
| 1047 | As opposed to atoi or strtol, grok_atoUV does NOT allow optional |
| 1048 | leading whitespace, or negative inputs. If such features are |
| 1049 | required, the calling code needs to explicitly implement those. |
| 1050 | |
| 1051 | Returns true if a valid value could be parsed. In that case, valptr |
| 1052 | is set to the parsed value, and endptr (if provided) is set to point |
| 1053 | to the character after the last digit. |
| 1054 | |
| 1055 | Returns false otherwise. This can happen if a) there is a leading zero |
| 1056 | followed by another digit; b) the digits would overflow a UV; or c) |
| 1057 | there are trailing non-digits AND endptr is not provided. |
| 1058 | |
| 1059 | Background: atoi has severe problems with illegal inputs, it cannot be |
| 1060 | used for incremental parsing, and therefore should be avoided |
| 1061 | atoi and strtol are also affected by locale settings, which can also be |
| 1062 | seen as a bug (global state controlled by user environment). |
| 1063 | |
| 1064 | */ |
| 1065 | |
| 1066 | bool |
| 1067 | Perl_grok_atoUV(const char *pv, UV *valptr, const char** endptr) |
| 1068 | { |
| 1069 | const char* s = pv; |
| 1070 | const char** eptr; |
| 1071 | const char* end2; /* Used in case endptr is NULL. */ |
| 1072 | UV val = 0; /* The parsed value. */ |
| 1073 | |
| 1074 | PERL_ARGS_ASSERT_GROK_ATOUV; |
| 1075 | |
| 1076 | eptr = endptr ? endptr : &end2; |
| 1077 | if (isDIGIT(*s)) { |
| 1078 | /* Single-digit inputs are quite common. */ |
| 1079 | val = *s++ - '0'; |
| 1080 | if (isDIGIT(*s)) { |
| 1081 | /* Fail on extra leading zeros. */ |
| 1082 | if (val == 0) |
| 1083 | return FALSE; |
| 1084 | while (isDIGIT(*s)) { |
| 1085 | /* This could be unrolled like in grok_number(), but |
| 1086 | * the expected uses of this are not speed-needy, and |
| 1087 | * unlikely to need full 64-bitness. */ |
| 1088 | U8 digit = *s++ - '0'; |
| 1089 | if (val < uv_max_div_10 || |
| 1090 | (val == uv_max_div_10 && digit <= uv_max_mod_10)) { |
| 1091 | val = val * 10 + digit; |
| 1092 | } else { |
| 1093 | return FALSE; |
| 1094 | } |
| 1095 | } |
| 1096 | } |
| 1097 | } |
| 1098 | if (s == pv) |
| 1099 | return FALSE; |
| 1100 | if (endptr == NULL && *s) |
| 1101 | return FALSE; /* If endptr is NULL, no trailing non-digits allowed. */ |
| 1102 | *eptr = s; |
| 1103 | *valptr = val; |
| 1104 | return TRUE; |
| 1105 | } |
| 1106 | |
| 1107 | #ifndef USE_QUADMATH |
| 1108 | STATIC NV |
| 1109 | S_mulexp10(NV value, I32 exponent) |
| 1110 | { |
| 1111 | NV result = 1.0; |
| 1112 | NV power = 10.0; |
| 1113 | bool negative = 0; |
| 1114 | I32 bit; |
| 1115 | |
| 1116 | if (exponent == 0) |
| 1117 | return value; |
| 1118 | if (value == 0) |
| 1119 | return (NV)0; |
| 1120 | |
| 1121 | /* On OpenVMS VAX we by default use the D_FLOAT double format, |
| 1122 | * and that format does not have *easy* capabilities [1] for |
| 1123 | * overflowing doubles 'silently' as IEEE fp does. We also need |
| 1124 | * to support G_FLOAT on both VAX and Alpha, and though the exponent |
| 1125 | * range is much larger than D_FLOAT it still doesn't do silent |
| 1126 | * overflow. Therefore we need to detect early whether we would |
| 1127 | * overflow (this is the behaviour of the native string-to-float |
| 1128 | * conversion routines, and therefore of native applications, too). |
| 1129 | * |
| 1130 | * [1] Trying to establish a condition handler to trap floating point |
| 1131 | * exceptions is not a good idea. */ |
| 1132 | |
| 1133 | /* In UNICOS and in certain Cray models (such as T90) there is no |
| 1134 | * IEEE fp, and no way at all from C to catch fp overflows gracefully. |
| 1135 | * There is something you can do if you are willing to use some |
| 1136 | * inline assembler: the instruction is called DFI-- but that will |
| 1137 | * disable *all* floating point interrupts, a little bit too large |
| 1138 | * a hammer. Therefore we need to catch potential overflows before |
| 1139 | * it's too late. */ |
| 1140 | |
| 1141 | #if ((defined(VMS) && !defined(_IEEE_FP)) || defined(_UNICOS)) && defined(NV_MAX_10_EXP) |
| 1142 | STMT_START { |
| 1143 | const NV exp_v = log10(value); |
| 1144 | if (exponent >= NV_MAX_10_EXP || exponent + exp_v >= NV_MAX_10_EXP) |
| 1145 | return NV_MAX; |
| 1146 | if (exponent < 0) { |
| 1147 | if (-(exponent + exp_v) >= NV_MAX_10_EXP) |
| 1148 | return 0.0; |
| 1149 | while (-exponent >= NV_MAX_10_EXP) { |
| 1150 | /* combination does not overflow, but 10^(-exponent) does */ |
| 1151 | value /= 10; |
| 1152 | ++exponent; |
| 1153 | } |
| 1154 | } |
| 1155 | } STMT_END; |
| 1156 | #endif |
| 1157 | |
| 1158 | if (exponent < 0) { |
| 1159 | negative = 1; |
| 1160 | exponent = -exponent; |
| 1161 | #ifdef NV_MAX_10_EXP |
| 1162 | /* for something like 1234 x 10^-309, the action of calculating |
| 1163 | * the intermediate value 10^309 then returning 1234 / (10^309) |
| 1164 | * will fail, since 10^309 becomes infinity. In this case try to |
| 1165 | * refactor it as 123 / (10^308) etc. |
| 1166 | */ |
| 1167 | while (value && exponent > NV_MAX_10_EXP) { |
| 1168 | exponent--; |
| 1169 | value /= 10; |
| 1170 | } |
| 1171 | if (value == 0.0) |
| 1172 | return value; |
| 1173 | #endif |
| 1174 | } |
| 1175 | #if defined(__osf__) |
| 1176 | /* Even with cc -ieee + ieee_set_fp_control(IEEE_TRAP_ENABLE_INV) |
| 1177 | * Tru64 fp behavior on inf/nan is somewhat broken. Another way |
| 1178 | * to do this would be ieee_set_fp_control(IEEE_TRAP_ENABLE_OVF) |
| 1179 | * but that breaks another set of infnan.t tests. */ |
| 1180 | # define FP_OVERFLOWS_TO_ZERO |
| 1181 | #endif |
| 1182 | for (bit = 1; exponent; bit <<= 1) { |
| 1183 | if (exponent & bit) { |
| 1184 | exponent ^= bit; |
| 1185 | result *= power; |
| 1186 | #ifdef FP_OVERFLOWS_TO_ZERO |
| 1187 | if (result == 0) |
| 1188 | return value < 0 ? -NV_INF : NV_INF; |
| 1189 | #endif |
| 1190 | /* Floating point exceptions are supposed to be turned off, |
| 1191 | * but if we're obviously done, don't risk another iteration. |
| 1192 | */ |
| 1193 | if (exponent == 0) break; |
| 1194 | } |
| 1195 | power *= power; |
| 1196 | } |
| 1197 | return negative ? value / result : value * result; |
| 1198 | } |
| 1199 | #endif /* #ifndef USE_QUADMATH */ |
| 1200 | |
| 1201 | NV |
| 1202 | Perl_my_atof(pTHX_ const char* s) |
| 1203 | { |
| 1204 | NV x = 0.0; |
| 1205 | #ifdef USE_QUADMATH |
| 1206 | Perl_my_atof2(aTHX_ s, &x); |
| 1207 | return x; |
| 1208 | #else |
| 1209 | # ifdef USE_LOCALE_NUMERIC |
| 1210 | PERL_ARGS_ASSERT_MY_ATOF; |
| 1211 | |
| 1212 | { |
| 1213 | DECLARATION_FOR_LC_NUMERIC_MANIPULATION; |
| 1214 | STORE_LC_NUMERIC_SET_TO_NEEDED(); |
| 1215 | if (PL_numeric_radix_sv && IN_LC(LC_NUMERIC)) { |
| 1216 | const char *standard = NULL, *local = NULL; |
| 1217 | bool use_standard_radix; |
| 1218 | |
| 1219 | /* Look through the string for the first thing that looks like a |
| 1220 | * decimal point: either the value in the current locale or the |
| 1221 | * standard fallback of '.'. The one which appears earliest in the |
| 1222 | * input string is the one that we should have atof look for. Note |
| 1223 | * that we have to determine this beforehand because on some |
| 1224 | * systems, Perl_atof2 is just a wrapper around the system's atof. |
| 1225 | * */ |
| 1226 | standard = strchr(s, '.'); |
| 1227 | local = strstr(s, SvPV_nolen(PL_numeric_radix_sv)); |
| 1228 | |
| 1229 | use_standard_radix = standard && (!local || standard < local); |
| 1230 | |
| 1231 | if (use_standard_radix) |
| 1232 | SET_NUMERIC_STANDARD(); |
| 1233 | |
| 1234 | Perl_atof2(s, x); |
| 1235 | |
| 1236 | if (use_standard_radix) |
| 1237 | SET_NUMERIC_UNDERLYING(); |
| 1238 | } |
| 1239 | else |
| 1240 | Perl_atof2(s, x); |
| 1241 | RESTORE_LC_NUMERIC(); |
| 1242 | } |
| 1243 | # else |
| 1244 | Perl_atof2(s, x); |
| 1245 | # endif |
| 1246 | #endif |
| 1247 | return x; |
| 1248 | } |
| 1249 | |
| 1250 | |
| 1251 | #ifdef USING_MSVC6 |
| 1252 | # pragma warning(push) |
| 1253 | # pragma warning(disable:4756;disable:4056) |
| 1254 | #endif |
| 1255 | static char* |
| 1256 | S_my_atof_infnan(pTHX_ const char* s, bool negative, const char* send, NV* value) |
| 1257 | { |
| 1258 | const char *p0 = negative ? s - 1 : s; |
| 1259 | const char *p = p0; |
| 1260 | int infnan = grok_infnan(&p, send); |
| 1261 | if (infnan && p != p0) { |
| 1262 | /* If we can generate inf/nan directly, let's do so. */ |
| 1263 | #ifdef NV_INF |
| 1264 | if ((infnan & IS_NUMBER_INFINITY)) { |
| 1265 | *value = (infnan & IS_NUMBER_NEG) ? -NV_INF: NV_INF; |
| 1266 | return (char*)p; |
| 1267 | } |
| 1268 | #endif |
| 1269 | #ifdef NV_NAN |
| 1270 | if ((infnan & IS_NUMBER_NAN)) { |
| 1271 | *value = NV_NAN; |
| 1272 | return (char*)p; |
| 1273 | } |
| 1274 | #endif |
| 1275 | #ifdef Perl_strtod |
| 1276 | /* If still here, we didn't have either NV_INF or NV_NAN, |
| 1277 | * and can try falling back to native strtod/strtold. |
| 1278 | * |
| 1279 | * (Though, are our NV_INF or NV_NAN ever not defined?) |
| 1280 | * |
| 1281 | * The native interface might not recognize all the possible |
| 1282 | * inf/nan strings Perl recognizes. What we can try |
| 1283 | * is to try faking the input. We will try inf/-inf/nan |
| 1284 | * as the most promising/portable input. */ |
| 1285 | { |
| 1286 | const char* fake = NULL; |
| 1287 | char* endp; |
| 1288 | NV nv; |
| 1289 | if ((infnan & IS_NUMBER_INFINITY)) { |
| 1290 | fake = ((infnan & IS_NUMBER_NEG)) ? "-inf" : "inf"; |
| 1291 | } |
| 1292 | else if ((infnan & IS_NUMBER_NAN)) { |
| 1293 | fake = "nan"; |
| 1294 | } |
| 1295 | assert(fake); |
| 1296 | nv = Perl_strtod(fake, &endp); |
| 1297 | if (fake != endp) { |
| 1298 | if ((infnan & IS_NUMBER_INFINITY)) { |
| 1299 | #ifdef Perl_isinf |
| 1300 | if (Perl_isinf(nv)) |
| 1301 | *value = nv; |
| 1302 | #else |
| 1303 | /* last resort, may generate SIGFPE */ |
| 1304 | *value = Perl_exp((NV)1e9); |
| 1305 | if ((infnan & IS_NUMBER_NEG)) |
| 1306 | *value = -*value; |
| 1307 | #endif |
| 1308 | return (char*)p; /* p, not endp */ |
| 1309 | } |
| 1310 | else if ((infnan & IS_NUMBER_NAN)) { |
| 1311 | #ifdef Perl_isnan |
| 1312 | if (Perl_isnan(nv)) |
| 1313 | *value = nv; |
| 1314 | #else |
| 1315 | /* last resort, may generate SIGFPE */ |
| 1316 | *value = Perl_log((NV)-1.0); |
| 1317 | #endif |
| 1318 | return (char*)p; /* p, not endp */ |
| 1319 | } |
| 1320 | } |
| 1321 | } |
| 1322 | #endif /* #ifdef Perl_strtod */ |
| 1323 | } |
| 1324 | return NULL; |
| 1325 | } |
| 1326 | #ifdef USING_MSVC6 |
| 1327 | # pragma warning(pop) |
| 1328 | #endif |
| 1329 | |
| 1330 | char* |
| 1331 | Perl_my_atof2(pTHX_ const char* orig, NV* value) |
| 1332 | { |
| 1333 | const char* s = orig; |
| 1334 | NV result[3] = {0.0, 0.0, 0.0}; |
| 1335 | #if defined(USE_PERL_ATOF) || defined(USE_QUADMATH) |
| 1336 | const char* send = s + strlen(orig); /* one past the last */ |
| 1337 | bool negative = 0; |
| 1338 | #endif |
| 1339 | #if defined(USE_PERL_ATOF) && !defined(USE_QUADMATH) |
| 1340 | UV accumulator[2] = {0,0}; /* before/after dp */ |
| 1341 | bool seen_digit = 0; |
| 1342 | I32 exp_adjust[2] = {0,0}; |
| 1343 | I32 exp_acc[2] = {-1, -1}; |
| 1344 | /* the current exponent adjust for the accumulators */ |
| 1345 | I32 exponent = 0; |
| 1346 | I32 seen_dp = 0; |
| 1347 | I32 digit = 0; |
| 1348 | I32 old_digit = 0; |
| 1349 | I32 sig_digits = 0; /* noof significant digits seen so far */ |
| 1350 | #endif |
| 1351 | |
| 1352 | #if defined(USE_PERL_ATOF) || defined(USE_QUADMATH) |
| 1353 | PERL_ARGS_ASSERT_MY_ATOF2; |
| 1354 | |
| 1355 | /* leading whitespace */ |
| 1356 | while (isSPACE(*s)) |
| 1357 | ++s; |
| 1358 | |
| 1359 | /* sign */ |
| 1360 | switch (*s) { |
| 1361 | case '-': |
| 1362 | negative = 1; |
| 1363 | /* FALLTHROUGH */ |
| 1364 | case '+': |
| 1365 | ++s; |
| 1366 | } |
| 1367 | #endif |
| 1368 | |
| 1369 | #ifdef USE_QUADMATH |
| 1370 | { |
| 1371 | char* endp; |
| 1372 | if ((endp = S_my_atof_infnan(aTHX_ s, negative, send, value))) |
| 1373 | return endp; |
| 1374 | result[2] = strtoflt128(s, &endp); |
| 1375 | if (s != endp) { |
| 1376 | *value = negative ? -result[2] : result[2]; |
| 1377 | return endp; |
| 1378 | } |
| 1379 | return NULL; |
| 1380 | } |
| 1381 | #elif defined(USE_PERL_ATOF) |
| 1382 | |
| 1383 | /* There is no point in processing more significant digits |
| 1384 | * than the NV can hold. Note that NV_DIG is a lower-bound value, |
| 1385 | * while we need an upper-bound value. We add 2 to account for this; |
| 1386 | * since it will have been conservative on both the first and last digit. |
| 1387 | * For example a 32-bit mantissa with an exponent of 4 would have |
| 1388 | * exact values in the set |
| 1389 | * 4 |
| 1390 | * 8 |
| 1391 | * .. |
| 1392 | * 17179869172 |
| 1393 | * 17179869176 |
| 1394 | * 17179869180 |
| 1395 | * |
| 1396 | * where for the purposes of calculating NV_DIG we would have to discount |
| 1397 | * both the first and last digit, since neither can hold all values from |
| 1398 | * 0..9; but for calculating the value we must examine those two digits. |
| 1399 | */ |
| 1400 | #ifdef MAX_SIG_DIG_PLUS |
| 1401 | /* It is not necessarily the case that adding 2 to NV_DIG gets all the |
| 1402 | possible digits in a NV, especially if NVs are not IEEE compliant |
| 1403 | (e.g., long doubles on IRIX) - Allen <allens@cpan.org> */ |
| 1404 | # define MAX_SIG_DIGITS (NV_DIG+MAX_SIG_DIG_PLUS) |
| 1405 | #else |
| 1406 | # define MAX_SIG_DIGITS (NV_DIG+2) |
| 1407 | #endif |
| 1408 | |
| 1409 | /* the max number we can accumulate in a UV, and still safely do 10*N+9 */ |
| 1410 | #define MAX_ACCUMULATE ( (UV) ((UV_MAX - 9)/10)) |
| 1411 | |
| 1412 | { |
| 1413 | const char* endp; |
| 1414 | if ((endp = S_my_atof_infnan(aTHX_ s, negative, send, value))) |
| 1415 | return (char*)endp; |
| 1416 | } |
| 1417 | |
| 1418 | /* we accumulate digits into an integer; when this becomes too |
| 1419 | * large, we add the total to NV and start again */ |
| 1420 | |
| 1421 | while (1) { |
| 1422 | if (isDIGIT(*s)) { |
| 1423 | seen_digit = 1; |
| 1424 | old_digit = digit; |
| 1425 | digit = *s++ - '0'; |
| 1426 | if (seen_dp) |
| 1427 | exp_adjust[1]++; |
| 1428 | |
| 1429 | /* don't start counting until we see the first significant |
| 1430 | * digit, eg the 5 in 0.00005... */ |
| 1431 | if (!sig_digits && digit == 0) |
| 1432 | continue; |
| 1433 | |
| 1434 | if (++sig_digits > MAX_SIG_DIGITS) { |
| 1435 | /* limits of precision reached */ |
| 1436 | if (digit > 5) { |
| 1437 | ++accumulator[seen_dp]; |
| 1438 | } else if (digit == 5) { |
| 1439 | if (old_digit % 2) { /* round to even - Allen */ |
| 1440 | ++accumulator[seen_dp]; |
| 1441 | } |
| 1442 | } |
| 1443 | if (seen_dp) { |
| 1444 | exp_adjust[1]--; |
| 1445 | } else { |
| 1446 | exp_adjust[0]++; |
| 1447 | } |
| 1448 | /* skip remaining digits */ |
| 1449 | while (isDIGIT(*s)) { |
| 1450 | ++s; |
| 1451 | if (! seen_dp) { |
| 1452 | exp_adjust[0]++; |
| 1453 | } |
| 1454 | } |
| 1455 | /* warn of loss of precision? */ |
| 1456 | } |
| 1457 | else { |
| 1458 | if (accumulator[seen_dp] > MAX_ACCUMULATE) { |
| 1459 | /* add accumulator to result and start again */ |
| 1460 | result[seen_dp] = S_mulexp10(result[seen_dp], |
| 1461 | exp_acc[seen_dp]) |
| 1462 | + (NV)accumulator[seen_dp]; |
| 1463 | accumulator[seen_dp] = 0; |
| 1464 | exp_acc[seen_dp] = 0; |
| 1465 | } |
| 1466 | accumulator[seen_dp] = accumulator[seen_dp] * 10 + digit; |
| 1467 | ++exp_acc[seen_dp]; |
| 1468 | } |
| 1469 | } |
| 1470 | else if (!seen_dp && GROK_NUMERIC_RADIX(&s, send)) { |
| 1471 | seen_dp = 1; |
| 1472 | if (sig_digits > MAX_SIG_DIGITS) { |
| 1473 | do { |
| 1474 | ++s; |
| 1475 | } while (isDIGIT(*s)); |
| 1476 | break; |
| 1477 | } |
| 1478 | } |
| 1479 | else { |
| 1480 | break; |
| 1481 | } |
| 1482 | } |
| 1483 | |
| 1484 | result[0] = S_mulexp10(result[0], exp_acc[0]) + (NV)accumulator[0]; |
| 1485 | if (seen_dp) { |
| 1486 | result[1] = S_mulexp10(result[1], exp_acc[1]) + (NV)accumulator[1]; |
| 1487 | } |
| 1488 | |
| 1489 | if (seen_digit && (isALPHA_FOLD_EQ(*s, 'e'))) { |
| 1490 | bool expnegative = 0; |
| 1491 | |
| 1492 | ++s; |
| 1493 | switch (*s) { |
| 1494 | case '-': |
| 1495 | expnegative = 1; |
| 1496 | /* FALLTHROUGH */ |
| 1497 | case '+': |
| 1498 | ++s; |
| 1499 | } |
| 1500 | while (isDIGIT(*s)) |
| 1501 | exponent = exponent * 10 + (*s++ - '0'); |
| 1502 | if (expnegative) |
| 1503 | exponent = -exponent; |
| 1504 | } |
| 1505 | |
| 1506 | |
| 1507 | |
| 1508 | /* now apply the exponent */ |
| 1509 | |
| 1510 | if (seen_dp) { |
| 1511 | result[2] = S_mulexp10(result[0],exponent+exp_adjust[0]) |
| 1512 | + S_mulexp10(result[1],exponent-exp_adjust[1]); |
| 1513 | } else { |
| 1514 | result[2] = S_mulexp10(result[0],exponent+exp_adjust[0]); |
| 1515 | } |
| 1516 | |
| 1517 | /* now apply the sign */ |
| 1518 | if (negative) |
| 1519 | result[2] = -result[2]; |
| 1520 | #endif /* USE_PERL_ATOF */ |
| 1521 | *value = result[2]; |
| 1522 | return (char *)s; |
| 1523 | } |
| 1524 | |
| 1525 | /* |
| 1526 | =for apidoc isinfnan |
| 1527 | |
| 1528 | C<Perl_isinfnan()> is utility function that returns true if the NV |
| 1529 | argument is either an infinity or a C<NaN>, false otherwise. To test |
| 1530 | in more detail, use C<Perl_isinf()> and C<Perl_isnan()>. |
| 1531 | |
| 1532 | This is also the logical inverse of Perl_isfinite(). |
| 1533 | |
| 1534 | =cut |
| 1535 | */ |
| 1536 | bool |
| 1537 | Perl_isinfnan(NV nv) |
| 1538 | { |
| 1539 | #ifdef Perl_isinf |
| 1540 | if (Perl_isinf(nv)) |
| 1541 | return TRUE; |
| 1542 | #endif |
| 1543 | #ifdef Perl_isnan |
| 1544 | if (Perl_isnan(nv)) |
| 1545 | return TRUE; |
| 1546 | #endif |
| 1547 | return FALSE; |
| 1548 | } |
| 1549 | |
| 1550 | /* |
| 1551 | =for apidoc |
| 1552 | |
| 1553 | Checks whether the argument would be either an infinity or C<NaN> when used |
| 1554 | as a number, but is careful not to trigger non-numeric or uninitialized |
| 1555 | warnings. it assumes the caller has done C<SvGETMAGIC(sv)> already. |
| 1556 | |
| 1557 | =cut |
| 1558 | */ |
| 1559 | |
| 1560 | bool |
| 1561 | Perl_isinfnansv(pTHX_ SV *sv) |
| 1562 | { |
| 1563 | PERL_ARGS_ASSERT_ISINFNANSV; |
| 1564 | if (!SvOK(sv)) |
| 1565 | return FALSE; |
| 1566 | if (SvNOKp(sv)) |
| 1567 | return Perl_isinfnan(SvNVX(sv)); |
| 1568 | if (SvIOKp(sv)) |
| 1569 | return FALSE; |
| 1570 | { |
| 1571 | STRLEN len; |
| 1572 | const char *s = SvPV_nomg_const(sv, len); |
| 1573 | return cBOOL(grok_infnan(&s, s+len)); |
| 1574 | } |
| 1575 | } |
| 1576 | |
| 1577 | #ifndef HAS_MODFL |
| 1578 | /* C99 has truncl, pre-C99 Solaris had aintl. We can use either with |
| 1579 | * copysignl to emulate modfl, which is in some platforms missing or |
| 1580 | * broken. */ |
| 1581 | # if defined(HAS_TRUNCL) && defined(HAS_COPYSIGNL) |
| 1582 | long double |
| 1583 | Perl_my_modfl(long double x, long double *ip) |
| 1584 | { |
| 1585 | *ip = truncl(x); |
| 1586 | return (x == *ip ? copysignl(0.0L, x) : x - *ip); |
| 1587 | } |
| 1588 | # elif defined(HAS_AINTL) && defined(HAS_COPYSIGNL) |
| 1589 | long double |
| 1590 | Perl_my_modfl(long double x, long double *ip) |
| 1591 | { |
| 1592 | *ip = aintl(x); |
| 1593 | return (x == *ip ? copysignl(0.0L, x) : x - *ip); |
| 1594 | } |
| 1595 | # endif |
| 1596 | #endif |
| 1597 | |
| 1598 | /* Similarly, with ilogbl and scalbnl we can emulate frexpl. */ |
| 1599 | #if ! defined(HAS_FREXPL) && defined(HAS_ILOGBL) && defined(HAS_SCALBNL) |
| 1600 | long double |
| 1601 | Perl_my_frexpl(long double x, int *e) { |
| 1602 | *e = x == 0.0L ? 0 : ilogbl(x) + 1; |
| 1603 | return (scalbnl(x, -*e)); |
| 1604 | } |
| 1605 | #endif |
| 1606 | |
| 1607 | /* |
| 1608 | =for apidoc Perl_signbit |
| 1609 | |
| 1610 | Return a non-zero integer if the sign bit on an NV is set, and 0 if |
| 1611 | it is not. |
| 1612 | |
| 1613 | If F<Configure> detects this system has a C<signbit()> that will work with |
| 1614 | our NVs, then we just use it via the C<#define> in F<perl.h>. Otherwise, |
| 1615 | fall back on this implementation. The main use of this function |
| 1616 | is catching C<-0.0>. |
| 1617 | |
| 1618 | C<Configure> notes: This function is called C<'Perl_signbit'> instead of a |
| 1619 | plain C<'signbit'> because it is easy to imagine a system having a C<signbit()> |
| 1620 | function or macro that doesn't happen to work with our particular choice |
| 1621 | of NVs. We shouldn't just re-C<#define> C<signbit> as C<Perl_signbit> and expect |
| 1622 | the standard system headers to be happy. Also, this is a no-context |
| 1623 | function (no C<pTHX_>) because C<Perl_signbit()> is usually re-C<#defined> in |
| 1624 | F<perl.h> as a simple macro call to the system's C<signbit()>. |
| 1625 | Users should just always call C<Perl_signbit()>. |
| 1626 | |
| 1627 | =cut |
| 1628 | */ |
| 1629 | #if !defined(HAS_SIGNBIT) |
| 1630 | int |
| 1631 | Perl_signbit(NV x) { |
| 1632 | # ifdef Perl_fp_class_nzero |
| 1633 | return Perl_fp_class_nzero(x); |
| 1634 | /* Try finding the high byte, and assume it's highest bit |
| 1635 | * is the sign. This assumption is probably wrong somewhere. */ |
| 1636 | # elif defined(USE_LONG_DOUBLE) && LONG_DOUBLEKIND == LONG_DOUBLE_IS_X86_80_BIT_LITTLE_ENDIAN |
| 1637 | return (((unsigned char *)&x)[9] & 0x80); |
| 1638 | # elif defined(NV_LITTLE_ENDIAN) |
| 1639 | /* Note that NVSIZE is sizeof(NV), which would make the below be |
| 1640 | * wrong if the end bytes are unused, which happens with the x86 |
| 1641 | * 80-bit long doubles, which is why take care of that above. */ |
| 1642 | return (((unsigned char *)&x)[NVSIZE - 1] & 0x80); |
| 1643 | # elif defined(NV_BIG_ENDIAN) |
| 1644 | return (((unsigned char *)&x)[0] & 0x80); |
| 1645 | # else |
| 1646 | /* This last resort fallback is wrong for the negative zero. */ |
| 1647 | return (x < 0.0) ? 1 : 0; |
| 1648 | # endif |
| 1649 | } |
| 1650 | #endif |
| 1651 | |
| 1652 | /* |
| 1653 | * ex: set ts=8 sts=4 sw=4 et: |
| 1654 | */ |