| /**************************************************************** |
| |
| The author of this software is David M. Gay. |
| |
| Copyright (C) 1998 by Lucent Technologies |
| All Rights Reserved |
| |
| Permission to use, copy, modify, and distribute this software and |
| its documentation for any purpose and without fee is hereby |
| granted, provided that the above copyright notice appear in all |
| copies and that both that the copyright notice and this |
| permission notice and warranty disclaimer appear in supporting |
| documentation, and that the name of Lucent or any of its entities |
| not be used in advertising or publicity pertaining to |
| distribution of the software without specific, written prior |
| permission. |
| |
| LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, |
| INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. |
| IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY |
| SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER |
| IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, |
| ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF |
| THIS SOFTWARE. |
| |
| ****************************************************************/ |
| |
| /* Please send bug reports to David M. Gay (dmg at acm dot org, |
| * with " at " changed at "@" and " dot " changed to "."). */ |
| |
| #include <_ansi.h> |
| #include <reent.h> |
| #include <string.h> |
| #include "mprec.h" |
| #include "gdtoa.h" |
| #include "gd_qnan.h" |
| #include "locale.h" |
| |
| unsigned char hexdig[256]; |
| |
| static void |
| _DEFUN (htinit, (h, s, inc), |
| unsigned char *h _AND |
| unsigned char *s _AND |
| int inc) |
| { |
| int i, j; |
| for(i = 0; (j = s[i]) !=0; i++) |
| h[j] = i + inc; |
| } |
| |
| void |
| _DEFUN_VOID (hexdig_init) |
| { |
| #define USC (unsigned char *) |
| htinit(hexdig, USC "0123456789", 0x10); |
| htinit(hexdig, USC "abcdef", 0x10 + 10); |
| htinit(hexdig, USC "ABCDEF", 0x10 + 10); |
| } |
| |
| static void |
| _DEFUN(rshift, (b, k), |
| _Bigint *b _AND |
| int k) |
| { |
| __ULong *x, *x1, *xe, y; |
| int n; |
| |
| x = x1 = b->_x; |
| n = k >> kshift; |
| if (n < b->_wds) { |
| xe = x + b->_wds; |
| x += n; |
| if (k &= kmask) { |
| n = ULbits - k; |
| y = *x++ >> k; |
| while(x < xe) { |
| *x1++ = (y | (*x << n)) & ALL_ON; |
| y = *x++ >> k; |
| } |
| if ((*x1 = y) !=0) |
| x1++; |
| } |
| else |
| while(x < xe) |
| *x1++ = *x++; |
| } |
| if ((b->_wds = x1 - b->_x) == 0) |
| b->_x[0] = 0; |
| } |
| |
| static _Bigint * |
| _DEFUN (increment, (ptr, b), |
| struct _reent *ptr _AND |
| _Bigint *b) |
| { |
| __ULong *x, *xe; |
| _Bigint *b1; |
| #ifdef Pack_16 |
| __ULong carry = 1, y; |
| #endif |
| |
| x = b->_x; |
| xe = x + b->_wds; |
| #ifdef Pack_32 |
| do { |
| if (*x < (__ULong)0xffffffffL) { |
| ++*x; |
| return b; |
| } |
| *x++ = 0; |
| } while(x < xe); |
| #else |
| do { |
| y = *x + carry; |
| carry = y >> 16; |
| *x++ = y & 0xffff; |
| if (!carry) |
| return b; |
| } while(x < xe); |
| if (carry) |
| #endif |
| { |
| if (b->_wds >= b->_maxwds) { |
| b1 = Balloc(ptr, b->_k+1); |
| Bcopy(b1, b); |
| Bfree(ptr, b); |
| b = b1; |
| } |
| b->_x[b->_wds++] = 1; |
| } |
| return b; |
| } |
| |
| |
| int |
| _DEFUN(gethex, (ptr, sp, fpi, exp, bp, sign), |
| struct _reent *ptr _AND |
| _CONST char **sp _AND |
| FPI *fpi _AND |
| Long *exp _AND |
| _Bigint **bp _AND |
| int sign) |
| { |
| _Bigint *b; |
| _CONST unsigned char *decpt, *s0, *s, *s1; |
| int esign, havedig, irv, k, n, nbits, up, zret; |
| __ULong L, lostbits, *x; |
| Long e, e1; |
| unsigned char *decimalpoint = (unsigned char *) |
| _localeconv_r (ptr)->decimal_point; |
| size_t decp_len = strlen ((const char *) decimalpoint); |
| unsigned char decp_end = decimalpoint[decp_len - 1]; |
| |
| if (!hexdig['0']) |
| hexdig_init(); |
| havedig = 0; |
| s0 = *(_CONST unsigned char **)sp + 2; |
| while(s0[havedig] == '0') |
| havedig++; |
| s0 += havedig; |
| s = s0; |
| decpt = 0; |
| zret = 0; |
| e = 0; |
| if (!hexdig[*s]) { |
| zret = 1; |
| if (strncmp ((const char *) s, (const char *) decimalpoint, |
| decp_len) != 0) |
| goto pcheck; |
| decpt = (s += decp_len); |
| if (!hexdig[*s]) |
| goto pcheck; |
| while(*s == '0') |
| s++; |
| if (hexdig[*s]) |
| zret = 0; |
| havedig = 1; |
| s0 = s; |
| } |
| while(hexdig[*s]) |
| s++; |
| if (strncmp ((const char *) s, (const char *) decimalpoint, |
| decp_len) == 0 |
| && !decpt) { |
| decpt = (s += decp_len); |
| while(hexdig[*s]) |
| s++; |
| } |
| if (decpt) |
| e = -(((Long)(s-decpt)) << 2); |
| pcheck: |
| s1 = s; |
| switch(*s) { |
| case 'p': |
| case 'P': |
| esign = 0; |
| switch(*++s) { |
| case '-': |
| esign = 1; |
| /* no break */ |
| case '+': |
| s++; |
| } |
| if ((n = hexdig[*s]) == 0 || n > 0x19) { |
| s = s1; |
| break; |
| } |
| e1 = n - 0x10; |
| while((n = hexdig[*++s]) !=0 && n <= 0x19) |
| e1 = 10*e1 + n - 0x10; |
| if (esign) |
| e1 = -e1; |
| e += e1; |
| } |
| *sp = (char*)s; |
| if (zret) |
| return havedig ? STRTOG_Zero : STRTOG_NoNumber; |
| n = s1 - s0 - 1; |
| for(k = 0; n > 7; n >>= 1) |
| k++; |
| b = Balloc(ptr, k); |
| x = b->_x; |
| n = 0; |
| L = 0; |
| while(s1 > s0) { |
| if (*--s1 == decp_end && s1 - decp_len + 1 >= s0 |
| && strncmp ((const char *) s1 - decp_len + 1, |
| (const char *) decimalpoint, decp_len) == 0) { |
| s1 -= decp_len - 1; /* Note the --s1 above! */ |
| continue; |
| } |
| if (n == 32) { |
| *x++ = L; |
| L = 0; |
| n = 0; |
| } |
| L |= (hexdig[*s1] & 0x0f) << n; |
| n += 4; |
| } |
| *x++ = L; |
| b->_wds = n = x - b->_x; |
| n = 32*n - hi0bits(L); |
| nbits = fpi->nbits; |
| lostbits = 0; |
| x = b->_x; |
| if (n > nbits) { |
| n -= nbits; |
| if (any_on(b,n)) { |
| lostbits = 1; |
| k = n - 1; |
| if (x[k>>kshift] & 1 << (k & kmask)) { |
| lostbits = 2; |
| if (k > 1 && any_on(b,k-1)) |
| lostbits = 3; |
| } |
| } |
| rshift(b, n); |
| e += n; |
| } |
| else if (n < nbits) { |
| n = nbits - n; |
| b = lshift(ptr, b, n); |
| e -= n; |
| x = b->_x; |
| } |
| if (e > fpi->emax) { |
| ovfl: |
| Bfree(ptr, b); |
| *bp = 0; |
| return STRTOG_Infinite | STRTOG_Overflow | STRTOG_Inexhi; |
| } |
| irv = STRTOG_Normal; |
| if (e < fpi->emin) { |
| irv = STRTOG_Denormal; |
| n = fpi->emin - e; |
| if (n >= nbits) { |
| switch (fpi->rounding) { |
| case FPI_Round_near: |
| if (n == nbits && (n < 2 || any_on(b,n-1))) |
| goto one_bit; |
| break; |
| case FPI_Round_up: |
| if (!sign) |
| goto one_bit; |
| break; |
| case FPI_Round_down: |
| if (sign) { |
| one_bit: |
| *exp = fpi->emin; |
| x[0] = b->_wds = 1; |
| *bp = b; |
| return STRTOG_Denormal | STRTOG_Inexhi |
| | STRTOG_Underflow; |
| } |
| } |
| Bfree(ptr, b); |
| *bp = 0; |
| return STRTOG_Zero | STRTOG_Inexlo | STRTOG_Underflow; |
| } |
| k = n - 1; |
| if (lostbits) |
| lostbits = 1; |
| else if (k > 0) |
| lostbits = any_on(b,k); |
| if (x[k>>kshift] & 1 << (k & kmask)) |
| lostbits |= 2; |
| nbits -= n; |
| rshift(b,n); |
| e = fpi->emin; |
| } |
| if (lostbits) { |
| up = 0; |
| switch(fpi->rounding) { |
| case FPI_Round_zero: |
| break; |
| case FPI_Round_near: |
| if ((lostbits & 2) |
| && ((lostbits & 1) | (x[0] & 1))) |
| up = 1; |
| break; |
| case FPI_Round_up: |
| up = 1 - sign; |
| break; |
| case FPI_Round_down: |
| up = sign; |
| } |
| if (up) { |
| k = b->_wds; |
| b = increment(ptr, b); |
| x = b->_x; |
| if (irv == STRTOG_Denormal) { |
| if (nbits == fpi->nbits - 1 |
| && x[nbits >> kshift] & 1 << (nbits & kmask)) |
| irv = STRTOG_Normal; |
| } |
| else if ((b->_wds > k) |
| || ((n = nbits & kmask) !=0 |
| && (hi0bits(x[k-1]) < 32-n))) { |
| rshift(b,1); |
| if (++e > fpi->emax) |
| goto ovfl; |
| } |
| irv |= STRTOG_Inexhi; |
| } |
| else |
| irv |= STRTOG_Inexlo; |
| } |
| *bp = b; |
| *exp = e; |
| return irv; |
| } |
| |