1/*
2 * Copyright (c) 1999
3 * Silicon Graphics Computer Systems, Inc.
4 *
5 * Copyright (c) 1999
6 * Boris Fomitchev
7 *
8 * This material is provided "as is", with absolutely no warranty expressed
9 * or implied. Any use is at your own risk.
10 *
11 * Permission to use or copy this software for any purpose is hereby granted
12 * without fee, provided the above notices are retained on all copies.
13 * Permission to modify the code and to distribute modified code is granted,
14 * provided the above notices are retained, and a notice that the code was
15 * modified is included with the above copyright notice.
16 *
17 */
18
19#include "stlport_prefix.h"
20
21#include <limits>
22#include <locale>
23#include <istream>
24
25#if (defined (__GNUC__) && !defined (__sun) && !defined (__hpux)) || \
26    defined (__DMC__)
27#  include <stdint.h>
28#endif
29
30#if defined (__linux__) || defined (__MINGW32__) || defined (__CYGWIN__) || \
31    defined (__BORLANDC__) || defined (__DMC__) || defined (__HP_aCC)
32
33#  if defined (__BORLANDC__)
34typedef unsigned int uint32_t;
35typedef unsigned __int64 uint64_t;
36#  endif
37
38union _ll {
39  uint64_t i64;
40  struct {
41#  if defined (_STLP_BIG_ENDIAN)
42    uint32_t hi;
43    uint32_t lo;
44#  elif defined (_STLP_LITTLE_ENDIAN)
45    uint32_t lo;
46    uint32_t hi;
47#  else
48#    error Unknown endianess
49#  endif
50  } i32;
51};
52
53#  if defined (__linux__) && !defined (__ANDROID__)
54#    include <ieee754.h>
55#  else
56union ieee854_long_double {
57  long double d;
58
59  /* This is the IEEE 854 double-extended-precision format.  */
60  struct {
61    unsigned int mantissa1:32;
62    unsigned int mantissa0:32;
63    unsigned int exponent:15;
64    unsigned int negative:1;
65    unsigned int empty:16;
66  } ieee;
67};
68
69#    define IEEE854_LONG_DOUBLE_BIAS 0x3fff
70#  endif
71#endif
72
73_STLP_BEGIN_NAMESPACE
74_STLP_MOVE_TO_PRIV_NAMESPACE
75
76//----------------------------------------------------------------------
77// num_get
78
79// Helper functions for _M_do_get_float.
80
81#if !defined (_STLP_NO_WCHAR_T)
82void  _STLP_CALL
83_Initialize_get_float( const ctype<wchar_t>& ct,
84                       wchar_t& Plus, wchar_t& Minus,
85                       wchar_t& pow_e, wchar_t& pow_E,
86                       wchar_t* digits) {
87  char ndigits[11] = "0123456789";
88  Plus  = ct.widen('+');
89  Minus = ct.widen('-');
90  pow_e = ct.widen('e');
91  pow_E = ct.widen('E');
92  ct.widen(ndigits + 0, ndigits + 10, digits);
93}
94#endif /* WCHAR_T */
95
96/*
97 * __string_to_double is just lifted from atof, the difference being
98 * that we just use '.' for the decimal point, rather than let it
99 * be taken from the current C locale, which of course is not accessible
100 * to us.
101 */
102#if defined (_STLP_MSVC) || defined (__BORLANDC__) || defined (__ICL)
103typedef unsigned long uint32;
104typedef unsigned __int64 uint64;
105#  define ULL(x) x##Ui64
106#elif defined (__unix) || defined (__MINGW32__) || \
107      (defined (__DMC__) && (__LONGLONG)) || defined (__WATCOMC__) || \
108      defined (__ANDROID__)
109typedef uint32_t uint32;
110typedef uint64_t uint64;
111#  define ULL(x) x##ULL
112#else
113#  error There should be some unsigned 64-bit integer on the system!
114#endif
115
116// Multiplication of two 64-bit integers, giving a 128-bit result.
117// Taken from Algorithm M in Knuth section 4.3.1, with the loop
118// hand-unrolled.
119static void _Stl_mult64(const uint64 u, const uint64 v,
120                        uint64& high, uint64& low) {
121  const uint64 low_mask = ULL(0xffffffff);
122  const uint64 u0 = u & low_mask;
123  const uint64 u1 = u >> 32;
124  const uint64 v0 = v & low_mask;
125  const uint64 v1 = v >> 32;
126
127  uint64 t = u0 * v0;
128  low = t & low_mask;
129
130  t = u1 * v0 + (t >> 32);
131  uint64 w1 = t & low_mask;
132  uint64 w2 = t >> 32;
133
134  uint64 x = u0 * v1 + w1;
135  low += (x & low_mask) << 32;
136  high = u1 * v1 + w2 + (x >> 32);
137}
138
139#if !defined (__linux__) || defined (__ANDROID__)
140
141#  define bit11 ULL(0x7ff)
142#  define exponent_mask (bit11 << 52)
143
144#  if !defined (__GNUC__) || (__GNUC__ != 3) || (__GNUC_MINOR__ != 4) || \
145      (!defined (__CYGWIN__) && !defined (__MINGW32__))
146//Generate bad code when compiled with -O2 option.
147inline
148#  endif
149void _Stl_set_exponent(uint64 &val, uint64 exp)
150{ val = (val & ~exponent_mask) | ((exp & bit11) << 52); }
151
152#endif // __linux__
153
154/* Power of ten fractions for tenscale*/
155/* The constants are factored so that at most two constants
156 * and two multiplies are needed. Furthermore, one of the constants
157 * is represented exactly - 10**n where 1<= n <= 27.
158 */
159
160static const uint64 _Stl_tenpow[80] = {
161ULL(0xa000000000000000), /* _Stl_tenpow[0]=(10**1)/(2**4) */
162ULL(0xc800000000000000), /* _Stl_tenpow[1]=(10**2)/(2**7) */
163ULL(0xfa00000000000000), /* _Stl_tenpow[2]=(10**3)/(2**10) */
164ULL(0x9c40000000000000), /* _Stl_tenpow[3]=(10**4)/(2**14) */
165ULL(0xc350000000000000), /* _Stl_tenpow[4]=(10**5)/(2**17) */
166ULL(0xf424000000000000), /* _Stl_tenpow[5]=(10**6)/(2**20) */
167ULL(0x9896800000000000), /* _Stl_tenpow[6]=(10**7)/(2**24) */
168ULL(0xbebc200000000000), /* _Stl_tenpow[7]=(10**8)/(2**27) */
169ULL(0xee6b280000000000), /* _Stl_tenpow[8]=(10**9)/(2**30) */
170ULL(0x9502f90000000000), /* _Stl_tenpow[9]=(10**10)/(2**34) */
171ULL(0xba43b74000000000), /* _Stl_tenpow[10]=(10**11)/(2**37) */
172ULL(0xe8d4a51000000000), /* _Stl_tenpow[11]=(10**12)/(2**40) */
173ULL(0x9184e72a00000000), /* _Stl_tenpow[12]=(10**13)/(2**44) */
174ULL(0xb5e620f480000000), /* _Stl_tenpow[13]=(10**14)/(2**47) */
175ULL(0xe35fa931a0000000), /* _Stl_tenpow[14]=(10**15)/(2**50) */
176ULL(0x8e1bc9bf04000000), /* _Stl_tenpow[15]=(10**16)/(2**54) */
177ULL(0xb1a2bc2ec5000000), /* _Stl_tenpow[16]=(10**17)/(2**57) */
178ULL(0xde0b6b3a76400000), /* _Stl_tenpow[17]=(10**18)/(2**60) */
179ULL(0x8ac7230489e80000), /* _Stl_tenpow[18]=(10**19)/(2**64) */
180ULL(0xad78ebc5ac620000), /* _Stl_tenpow[19]=(10**20)/(2**67) */
181ULL(0xd8d726b7177a8000), /* _Stl_tenpow[20]=(10**21)/(2**70) */
182ULL(0x878678326eac9000), /* _Stl_tenpow[21]=(10**22)/(2**74) */
183ULL(0xa968163f0a57b400), /* _Stl_tenpow[22]=(10**23)/(2**77) */
184ULL(0xd3c21bcecceda100), /* _Stl_tenpow[23]=(10**24)/(2**80) */
185ULL(0x84595161401484a0), /* _Stl_tenpow[24]=(10**25)/(2**84) */
186ULL(0xa56fa5b99019a5c8), /* _Stl_tenpow[25]=(10**26)/(2**87) */
187ULL(0xcecb8f27f4200f3a), /* _Stl_tenpow[26]=(10**27)/(2**90) */
188
189ULL(0xd0cf4b50cfe20766), /* _Stl_tenpow[27]=(10**55)/(2**183) */
190ULL(0xd2d80db02aabd62c), /* _Stl_tenpow[28]=(10**83)/(2**276) */
191ULL(0xd4e5e2cdc1d1ea96), /* _Stl_tenpow[29]=(10**111)/(2**369) */
192ULL(0xd6f8d7509292d603), /* _Stl_tenpow[30]=(10**139)/(2**462) */
193ULL(0xd910f7ff28069da4), /* _Stl_tenpow[31]=(10**167)/(2**555) */
194ULL(0xdb2e51bfe9d0696a), /* _Stl_tenpow[32]=(10**195)/(2**648) */
195ULL(0xdd50f1996b947519), /* _Stl_tenpow[33]=(10**223)/(2**741) */
196ULL(0xdf78e4b2bd342cf7), /* _Stl_tenpow[34]=(10**251)/(2**834) */
197ULL(0xe1a63853bbd26451), /* _Stl_tenpow[35]=(10**279)/(2**927) */
198ULL(0xe3d8f9e563a198e5), /* _Stl_tenpow[36]=(10**307)/(2**1020) */
199
200// /* _Stl_tenpow[36]=(10**335)/(2**) */
201// /* _Stl_tenpow[36]=(10**335)/(2**) */
202
203ULL(0xfd87b5f28300ca0e), /* _Stl_tenpow[37]=(10**-28)/(2**-93) */
204ULL(0xfb158592be068d2f), /* _Stl_tenpow[38]=(10**-56)/(2**-186) */
205ULL(0xf8a95fcf88747d94), /* _Stl_tenpow[39]=(10**-84)/(2**-279) */
206ULL(0xf64335bcf065d37d), /* _Stl_tenpow[40]=(10**-112)/(2**-372) */
207ULL(0xf3e2f893dec3f126), /* _Stl_tenpow[41]=(10**-140)/(2**-465) */
208ULL(0xf18899b1bc3f8ca2), /* _Stl_tenpow[42]=(10**-168)/(2**-558) */
209ULL(0xef340a98172aace5), /* _Stl_tenpow[43]=(10**-196)/(2**-651) */
210ULL(0xece53cec4a314ebe), /* _Stl_tenpow[44]=(10**-224)/(2**-744) */
211ULL(0xea9c227723ee8bcb), /* _Stl_tenpow[45]=(10**-252)/(2**-837)     */
212ULL(0xe858ad248f5c22ca), /* _Stl_tenpow[46]=(10**-280)/(2**-930) */
213ULL(0xe61acf033d1a45df), /* _Stl_tenpow[47]=(10**-308)/(2**-1023)    */
214ULL(0xe3e27a444d8d98b8), /* _Stl_tenpow[48]=(10**-336)/(2**-1116) */
215ULL(0xe1afa13afbd14d6e)  /* _Stl_tenpow[49]=(10**-364)/(2**-1209) */
216};
217
218static const short _Stl_twoexp[80] = {
2194,7,10,14,17,20,24,27,30,34,37,40,44,47,50,54,57,60,64,67,70,74,77,80,84,87,90,
220183,276,369,462,555,648,741,834,927,1020,
221-93,-186,-279,-372,-465,-558,-651,-744,-837,-930,-1023,-1116,-1209
222};
223
224#define  TEN_1  0           /* offset to 10 **   1 */
225#define  TEN_27   26        /* offset to 10 **  27 */
226#define  TEN_M28  37        /* offset to 10 ** -28 */
227#define  NUM_HI_P 11
228#define  NUM_HI_N 13
229
230#define _Stl_HIBITULL (ULL(1) << 63)
231
232static void _Stl_norm_and_round(uint64& p, int& norm, uint64 prodhi, uint64 prodlo) {
233  norm = 0;
234  if ((prodhi & _Stl_HIBITULL) == 0) {
235                                /* leading bit is a zero
236                                 * may have to normalize
237                                 */
238    if ((prodhi == ~_Stl_HIBITULL) &&
239        ((prodlo >> 62) == 0x3)) {  /* normalization followed by round
240                                     * would cause carry to create
241                                     * extra bit, so don't normalize
242                                     */
243      p = _Stl_HIBITULL;
244      return;
245    }
246    p = (prodhi << 1) | (prodlo >> 63); /* normalize */
247    norm = 1;
248    prodlo <<= 1;
249  }
250  else {
251    p = prodhi;
252  }
253
254  if ((prodlo & _Stl_HIBITULL) != 0) {     /* first guard bit a one */
255    if (((p & 0x1) != 0) ||
256        prodlo != _Stl_HIBITULL ) {    /* not borderline for round to even */
257      /* round */
258      ++p;
259      if (p == 0)
260        ++p;
261    }
262  }
263}
264
265// Convert a 64-bitb fraction * 10^exp to a 64-bit fraction * 2^bexp.
266// p:    64-bit fraction
267// exp:  base-10 exponent
268// bexp: base-2 exponent (output parameter)
269static void _Stl_tenscale(uint64& p, int exp, int& bexp) {
270  bexp = 0;
271
272  if ( exp == 0 ) {              /* no scaling needed */
273    return;
274  }
275
276  int exp_hi = 0, exp_lo = exp; /* exp = exp_hi*32 + exp_lo */
277  int tlo = TEN_1, thi;         /* offsets in power of ten table */
278  int num_hi;                   /* number of high exponent powers */
279
280  if (exp > 0) {                /* split exponent */
281    if (exp_lo > 27) {
282      exp_lo++;
283      while (exp_lo > 27) {
284        exp_hi++;
285        exp_lo -= 28;
286      }
287    }
288    thi = TEN_27;
289    num_hi = NUM_HI_P;
290  } else { // exp < 0
291    while (exp_lo < 0) {
292      exp_hi++;
293      exp_lo += 28;
294    }
295    thi = TEN_M28;
296    num_hi = NUM_HI_N;
297  }
298
299  uint64 prodhi, prodlo;        /* 128b product */
300  int norm;                     /* number of bits of normalization */
301
302  int hi, lo;                   /* offsets in power of ten table */
303  while (exp_hi) {              /* scale */
304    hi = (min) (exp_hi, num_hi);    /* only a few large powers of 10 */
305    exp_hi -= hi;               /* could iterate in extreme case */
306    hi += thi-1;
307    _Stl_mult64(p, _Stl_tenpow[hi], prodhi, prodlo);
308    _Stl_norm_and_round(p, norm, prodhi, prodlo);
309    bexp += _Stl_twoexp[hi] - norm;
310  }
311
312  if (exp_lo) {
313    lo = tlo + exp_lo -1;
314    _Stl_mult64(p, _Stl_tenpow[lo], prodhi, prodlo);
315    _Stl_norm_and_round(p, norm, prodhi, prodlo);
316    bexp += _Stl_twoexp[lo] - norm;
317  }
318
319  return;
320}
321
322// First argument is a buffer of values from 0 to 9, NOT ascii.
323// Second argument is number of digits in buffer, 1 <= digits <= 17.
324// Third argument is base-10 exponent.
325
326/* IEEE representation */
327#if !defined (__linux__) || defined (__ANDROID__)
328
329union _Double_rep {
330  uint64 ival;
331  double val;
332};
333
334static double _Stl_atod(char *buffer, ptrdiff_t ndigit, int dexp) {
335  typedef numeric_limits<double> limits;
336  _Double_rep drep;
337  uint64 &value = drep.ival;  /* Value develops as follows:
338                                 * 1) decimal digits as an integer
339                                 * 2) left adjusted fraction
340                                 * 3) right adjusted fraction
341                                 * 4) exponent and fraction
342                                 */
343
344  uint32 guard;         /* First guard bit */
345  uint64 rest;          /* Remaining guard bits */
346
347  int bexp;             /* binary exponent */
348  int nzero;            /* number of non-zero bits */
349  int sexp;             /* scaling exponent */
350
351  char *bufferend;              /* pointer to char after last digit */
352
353  /* Convert the decimal digits to a binary integer. */
354  bufferend = buffer + ndigit;
355  value = 0;
356
357  while (buffer < bufferend) {
358    value *= 10;
359    value += *buffer++;
360  }
361
362  /* Check for zero and treat it as a special case */
363  if (value == 0) {
364    return 0.0;
365  }
366
367  /* Normalize value */
368  bexp = 64;                    /* convert from 64b int to fraction */
369
370  /* Count number of non-zeroes in value */
371  nzero = 0;
372  if ((value >> 32) != 0) { nzero  = 32; }    //*TY 03/25/2000 - added explicit comparison to zero to avoid uint64 to bool conversion operator
373  if ((value >> (16 + nzero)) != 0) { nzero += 16; }
374  if ((value >> ( 8 + nzero)) != 0) { nzero +=  8; }
375  if ((value >> ( 4 + nzero)) != 0) { nzero +=  4; }
376  if ((value >> ( 2 + nzero)) != 0) { nzero +=  2; }
377  if ((value >> ( 1 + nzero)) != 0) { nzero +=  1; }
378  if ((value >> (     nzero)) != 0) { nzero +=  1; }
379
380  /* Normalize */
381  value <<= /*(uint64)*/ (64 - nzero);    //*TY 03/25/2000 - removed extraneous cast to uint64
382  bexp -= 64 - nzero;
383
384  /* At this point we have a 64b fraction and a binary exponent
385   * but have yet to incorporate the decimal exponent.
386   */
387
388  /* multiply by 10^dexp */
389  _Stl_tenscale(value, dexp, sexp);
390  bexp += sexp;
391
392  if (bexp <= -1022) {          /* HI denorm or underflow */
393    bexp += 1022;
394    if (bexp < -53) {          /* guaranteed underflow */
395      value = 0;
396    }
397    else {                      /* denorm or possible underflow */
398      int lead0 = 12 - bexp;          /* 12 sign and exponent bits */
399
400      /* we must special case right shifts of more than 63 */
401      if (lead0 > 64) {
402        rest = value;
403        guard = 0;
404        value = 0;
405      }
406      else if (lead0 == 64) {
407        rest = value & ((ULL(1)<< 63)-1);
408        guard = (uint32) ((value>> 63) & 1 );
409        value = 0;
410      }
411      else {
412        rest = value & (((ULL(1) << lead0)-1)-1);
413        guard = (uint32) (((value>> lead0)-1) & 1);
414        value >>= /*(uint64)*/ lead0; /* exponent is zero */
415      }
416
417      /* Round */
418      if (guard && ((value & 1) || rest) ) {
419        ++value;
420        if (value == (ULL(1) << (limits::digits - 1))) { /* carry created normal number */
421          value = 0;
422          _Stl_set_exponent(value, 1);
423        }
424      }
425    }
426  }
427  else {                        /* not zero or denorm */
428    /* Round to 53 bits */
429    rest = value & ((1 << 10) - 1);
430    value >>= 10;
431    guard = (uint32) value & 1;
432    value >>= 1;
433
434    /*  value&1 guard   rest    Action
435     *
436     *  dc      0       dc      none
437     *  1       1       dc      round
438     *  0       1       0       none
439     *  0       1       !=0     round
440     */
441    if (guard) {
442      if (((value&1)!=0) || (rest!=0)) {
443        ++value;                        /* round */
444        if ((value >> 53) != 0) {       /* carry all the way across */
445          value >>= 1;          /* renormalize */
446          ++bexp;
447        }
448      }
449    }
450    /*
451     * Check for overflow
452     * IEEE Double Precision Format
453     * (From Table 7-8 of Kane and Heinrich)
454     *
455     * Fraction bits               52
456     * Emax                     +1023
457     * Emin                     -1022
458     * Exponent bias            +1023
459     * Exponent bits               11
460     * Integer bit             hidden
461     * Total width in bits         64
462     */
463
464    if (bexp > limits::max_exponent) {          /* overflow */
465      return limits::infinity();
466    }
467    else {                      /* value is normal */
468      value &= ~(ULL(1) << (limits::digits - 1));   /* hide hidden bit */
469      _Stl_set_exponent(value, bexp + 1022); /* add bias */
470    }
471  }
472
473  _STLP_STATIC_ASSERT(sizeof(uint64) >= sizeof(double))
474  return drep.val;
475}
476
477#endif
478
479#if defined (__linux__) || defined (__MINGW32__) || defined (__CYGWIN__) || \
480    defined (__BORLANDC__) || defined (__DMC__) || defined (__HP_aCC)
481
482template <class D, class IEEE, int M, int BIAS>
483D _Stl_atodT(char *buffer, ptrdiff_t ndigit, int dexp)
484{
485  typedef numeric_limits<D> limits;
486
487  /* Convert the decimal digits to a binary integer. */
488  char *bufferend = buffer + ndigit; /* pointer to char after last digit */
489  _ll vv;
490  vv.i64 = 0L;
491
492  while ( buffer < bufferend ) {
493    vv.i64 *= 10;
494    vv.i64 += *buffer++;
495  }
496
497  if ( vv.i64 == ULL(0) ) { /* Check for zero and treat it as a special case */
498    return D(0.0);
499  }
500
501  /* Normalize value */
502
503  int bexp = 64; /* convert from 64b int to fraction */
504
505  /* Count number of non-zeroes in value */
506  int nzero = 0;
507  if ((vv.i64 >> 32) != 0) { nzero = 32; }
508  if ((vv.i64 >> (16 + nzero)) != 0) { nzero += 16; }
509  if ((vv.i64 >> ( 8 + nzero)) != 0) { nzero +=  8; }
510  if ((vv.i64 >> ( 4 + nzero)) != 0) { nzero +=  4; }
511  if ((vv.i64 >> ( 2 + nzero)) != 0) { nzero +=  2; }
512  if ((vv.i64 >> ( 1 + nzero)) != 0) { nzero +=  1; }
513  if ((vv.i64 >> (     nzero)) != 0) { nzero +=  1; }
514
515  /* Normalize */
516  nzero = 64 - nzero;
517  vv.i64 <<= nzero;    // * TY 03/25/2000 - removed extraneous cast to uint64
518  bexp -= nzero;
519
520  /* At this point we have a 64b fraction and a binary exponent
521   * but have yet to incorporate the decimal exponent.
522   */
523
524  /* multiply by 10^dexp */
525  int sexp;
526  _Stl_tenscale(vv.i64, dexp, sexp);
527  bexp += sexp;
528
529  if ( bexp >= limits::min_exponent ) { /* not zero or denorm */
530    if ( limits::digits < 64 ) {
531      /* Round to (64 - M + 1) bits */
532      uint64_t rest = vv.i64 & ((~ULL(0) / ULL(2)) >> (limits::digits - 1));
533      vv.i64 >>= M - 2;
534      uint32_t guard = (uint32) vv.i64 & 1;
535      vv.i64 >>= 1;
536
537      /*  value&1 guard   rest    Action
538       *
539       *  dc      0       dc      none
540       *  1       1       dc      round
541       *  0       1       0       none
542       *  0       1       !=0     round
543       */
544
545      if (guard) {
546        if ( ((vv.i64 & 1) != 0) || (rest != 0) ) {
547          vv.i64++;       /* round */
548          if ( (vv.i64 >> (limits::digits < 64 ? limits::digits : 0)) != 0 ) { /* carry all the way across */
549            vv.i64 >>= 1; /* renormalize */
550            ++bexp;
551          }
552        }
553      }
554
555      vv.i64 &= ~(ULL(1) << (limits::digits - 1)); /* hide hidden bit */
556    }
557    /*
558     * Check for overflow
559     * IEEE Double Precision Format
560     * (From Table 7-8 of Kane and Heinrich)
561     *
562     * Fraction bits               52
563     * Emax                     +1023
564     * Emin                     -1022
565     * Exponent bias            +1023
566     * Exponent bits               11
567     * Integer bit             hidden
568     * Total width in bits         64
569     */
570
571    if (bexp > limits::max_exponent) { /* overflow */
572      return limits::infinity();
573    }
574
575    /* value is normal */
576
577    IEEE v;
578
579    v.ieee.mantissa0 = vv.i32.hi;
580    v.ieee.mantissa1 = vv.i32.lo;
581    v.ieee.negative = 0;
582    v.ieee.exponent = bexp + BIAS - 1;
583
584    return v.d;
585  }
586
587  /* HI denorm or underflow */
588  bexp += BIAS - 1;
589  if (bexp < -limits::digits) { /* guaranteed underflow */
590    vv.i64 = 0;
591  } else {  /* denorm or possible underflow */
592
593    /*
594     * Problem point for long double: looks like this code reflect shareing of mantissa
595     * and exponent in 64b int; not so for long double
596     */
597
598    int lead0 = M - bexp; /* M = 12 sign and exponent bits */
599    uint64_t rest;
600    uint32_t guard;
601
602    /* we must special case right shifts of more than 63 */
603
604    if (lead0 > 64) {
605      rest = vv.i64;
606      guard = 0;
607      vv.i64 = 0;
608    } else if (lead0 == 64) {
609      rest = vv.i64 & ((ULL(1) << 63)-1);
610      guard = (uint32) ((vv.i64 >> 63) & 1 );
611      vv.i64 = 0;
612    } else {
613      rest = vv.i64 & (((ULL(1) << lead0)-1)-1);
614      guard = (uint32) (((vv.i64 >> lead0)-1) & 1);
615      vv.i64 >>= /*(uint64)*/ lead0; /* exponent is zero */
616    }
617
618    /* Round */
619    if (guard && ( (vv.i64 & 1) || rest)) {
620      vv.i64++;
621      if (vv.i64 == (ULL(1) << (limits::digits - 1))) { /* carry created normal number */
622        IEEE v;
623
624        v.ieee.mantissa0 = 0;
625        v.ieee.mantissa1 = 0;
626        v.ieee.negative = 0;
627        v.ieee.exponent = 1;
628        return v.d;
629      }
630    }
631  }
632
633  IEEE v;
634
635  v.ieee.mantissa0 = vv.i32.hi;
636  v.ieee.mantissa1 = vv.i32.lo;
637  v.ieee.negative = 0;
638  v.ieee.exponent = 0;
639
640  return v.d;
641}
642#endif // __linux__
643
644#if !defined (__linux__) || defined (__ANDROID__)
645static double _Stl_string_to_double(const char *s) {
646  typedef numeric_limits<double> limits;
647  const int max_digits = limits::digits10 + 2;
648  unsigned c;
649  unsigned Negate, decimal_point;
650  char *d;
651  int exp;
652  int dpchar;
653  char digits[max_digits];
654
655  c = *s++;
656
657  /* process sign */
658  Negate = 0;
659  if (c == '+') {
660    c = *s++;
661  } else if (c == '-') {
662    Negate = 1;
663    c = *s++;
664  }
665
666  d = digits;
667  dpchar = '.' - '0';
668  decimal_point = 0;
669  exp = 0;
670
671  for (;;) {
672    c -= '0';
673    if (c < 10) {
674      if (d == digits + max_digits) {
675        /* ignore more than max_digits digits, but adjust exponent */
676        exp += (decimal_point ^ 1);
677      } else {
678        if (c == 0 && d == digits) {
679          /* ignore leading zeros */
680        } else {
681          *d++ = (char) c;
682        }
683        exp -= decimal_point;
684      }
685    } else if (c == (unsigned int) dpchar && !decimal_point) { /* INTERNATIONAL */
686      decimal_point = 1;
687    } else {
688      break;
689    }
690    c = *s++;
691  }
692
693  /* strtod cant return until it finds the end of the exponent */
694  if (d == digits) {
695    return 0.0;
696  }
697
698  if (c == 'e' - '0' || c == 'E' - '0') {
699    register unsigned negate_exp = 0;
700    register int e = 0;
701    c = *s++;
702    if (c == '+' || c == ' ') {
703      c = *s++;
704    } else if (c == '-') {
705      negate_exp = 1;
706      c = *s++;
707    }
708    if (c -= '0', c < 10) {
709      do {
710        e = e * 10 + (int)c;
711        c = *s++;
712      } while (c -= '0', c < 10);
713
714      if (negate_exp) {
715        e = -e;
716      }
717      exp += e;
718    }
719  }
720
721  double x;
722  ptrdiff_t n = d - digits;
723  if ((exp + n - 1) < limits::min_exponent10) {
724    x = 0;
725  }
726  else if ((exp + n - 1) > limits::max_exponent10) {
727    x = limits::infinity();
728  }
729  else {
730    /* Let _Stl_atod diagnose under- and over-flows.
731     * If the input was == 0.0, we have already returned,
732     * so retval of +-Inf signals OVERFLOW, 0.0 UNDERFLOW */
733    x = _Stl_atod(digits, n, exp);
734  }
735
736  if (Negate) {
737    x = -x;
738  }
739
740  return x;
741}
742
743#endif
744
745#if defined (__linux__) || defined (__MINGW32__) || defined (__CYGWIN__) || \
746    defined (__BORLANDC__) || defined (__DMC__) || defined (__HP_aCC)
747
748template <class D, class IEEE, int M, int BIAS>
749D _Stl_string_to_doubleT(const char *s)
750{
751  typedef numeric_limits<D> limits;
752  const int max_digits = limits::digits10; /* + 2 17 */;
753  unsigned c;
754  unsigned decimal_point;
755  char *d;
756  int exp;
757  D x;
758  int dpchar;
759  char digits[max_digits];
760
761  c = *s++;
762
763  /* process sign */
764  bool Negate = false;
765  if (c == '+') {
766    c = *s++;
767  } else if (c == '-') {
768    Negate = true;
769    c = *s++;
770  }
771
772  d = digits;
773  dpchar = '.' - '0';
774  decimal_point = 0;
775  exp = 0;
776
777  for (;;) {
778    c -= '0';
779    if (c < 10) {
780      if (d == digits + max_digits) {
781        /* ignore more than max_digits digits, but adjust exponent */
782        exp += (decimal_point ^ 1);
783      } else {
784        if (c == 0 && d == digits) {
785          /* ignore leading zeros */
786        } else {
787          *d++ = (char) c;
788        }
789        exp -= decimal_point;
790      }
791    } else if (c == (unsigned int) dpchar && !decimal_point) {    /* INTERNATIONAL */
792      decimal_point = 1;
793    } else {
794      break;
795    }
796    c = *s++;
797  }
798  /* strtod cant return until it finds the end of the exponent */
799  if (d == digits) {
800    return D(0.0);
801  }
802
803  if (c == 'e'-'0' || c == 'E'-'0') {
804    bool negate_exp = false;
805    register int e = 0;
806    c = *s++;
807    if (c == '+' || c == ' ') {
808      c = *s++;
809    } else if (c == '-') {
810      negate_exp = true;
811      c = *s++;
812    }
813    if (c -= '0', c < 10) {
814      do {
815        e = e * 10 + (int)c;
816        c = *s++;
817      } while (c -= '0', c < 10);
818
819      if (negate_exp) {
820        e = -e;
821      }
822      exp += e;
823    }
824  }
825
826  ptrdiff_t n = d - digits;
827  if ((exp + n - 1) < limits::min_exponent10) {
828    return D(0.0); // +0.0 is the same as -0.0
829  } else if ((exp + n - 1) > limits::max_exponent10 ) {
830    // not good, because of x = -x below; this may lead to portability problems
831    x = limits::infinity();
832  } else {
833    /* let _Stl_atod diagnose under- and over-flows */
834    /* if the input was == 0.0, we have already returned,
835       so retval of +-Inf signals OVERFLOW, 0.0 UNDERFLOW
836    */
837    x = _Stl_atodT<D,IEEE,M,BIAS>(digits, n, exp);
838  }
839
840  return Negate ? -x : x;
841}
842
843#endif // __linux__
844
845void _STLP_CALL
846__string_to_float(const __iostring& v, float& val)
847{
848#if !defined (__linux__) || defined (__ANDROID__)
849  val = (float)_Stl_string_to_double(v.c_str());
850#else
851  val = (float)_Stl_string_to_doubleT<double,ieee754_double,12,IEEE754_DOUBLE_BIAS>(v.c_str());
852#endif
853}
854
855void _STLP_CALL
856__string_to_float(const __iostring& v, double& val)
857{
858#if !defined (__linux__) || defined (__ANDROID__)
859  val = _Stl_string_to_double(v.c_str());
860#else
861  val = _Stl_string_to_doubleT<double,ieee754_double,12,IEEE754_DOUBLE_BIAS>(v.c_str());
862#endif
863}
864
865#if !defined (_STLP_NO_LONG_DOUBLE)
866void _STLP_CALL
867__string_to_float(const __iostring& v, long double& val) {
868#if !defined (__linux__) && !defined (__MINGW32__) && !defined (__CYGWIN__) && \
869    !defined (__BORLANDC__) && !defined (__DMC__) && !defined (__HP_aCC)
870  //The following function is valid only if long double is an alias for double.
871  _STLP_STATIC_ASSERT( sizeof(long double) <= sizeof(double) )
872  val = _Stl_string_to_double(v.c_str());
873#else
874  val = _Stl_string_to_doubleT<long double,ieee854_long_double,16,IEEE854_LONG_DOUBLE_BIAS>(v.c_str());
875#endif
876}
877#endif
878
879_STLP_MOVE_TO_STD_NAMESPACE
880_STLP_END_NAMESPACE
881
882// Local Variables:
883// mode:C++
884// End:
885