diff options
author | das <das@FreeBSD.org> | 2003-03-12 20:18:32 +0000 |
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committer | das <das@FreeBSD.org> | 2003-03-12 20:18:32 +0000 |
commit | db3a0f1435efcb4461005cb8d8509bff01f9b018 (patch) | |
tree | 632bc138392cfc4c37a7e12065afe443d31145eb /contrib/gdtoa/hexnan.c | |
download | FreeBSD-src-db3a0f1435efcb4461005cb8d8509bff01f9b018.zip FreeBSD-src-db3a0f1435efcb4461005cb8d8509bff01f9b018.tar.gz |
Initial import of David Gay's gdtoa library for conversion between
strings and floating point.
Diffstat (limited to 'contrib/gdtoa/hexnan.c')
-rw-r--r-- | contrib/gdtoa/hexnan.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/contrib/gdtoa/hexnan.c b/contrib/gdtoa/hexnan.c new file mode 100644 index 0000000..7a7e03a --- /dev/null +++ b/contrib/gdtoa/hexnan.c @@ -0,0 +1,137 @@ +/**************************************************************** + +The author of this software is David M. Gay. + +Copyright (C) 2000 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 + Bell Laboratories, Room 2C-463 + 600 Mountain Avenue + Murray Hill, NJ 07974-0636 + U.S.A. + dmg@bell-labs.com + */ + +#include "gdtoaimp.h" + + static void +#ifdef KR_headers +L_shift(x, x1, i) ULong *x; ULong *x1; int i; +#else +L_shift(ULong *x, ULong *x1, int i) +#endif +{ + int j; + + i = 8 - i; + i <<= 2; + j = ULbits - i; + do { + *x |= x[1] << j; + x[1] >>= i; + } while(++x < x1); + } + + int +#ifdef KR_headers +hexnan(sp, fpi, x0) + CONST char **sp; FPI *fpi; ULong *x0; +#else +hexnan( CONST char **sp, FPI *fpi, ULong *x0) +#endif +{ + ULong c, h, *x, *x1, *xe; + CONST char *s; + int havedig, hd0, i, nbits; + + if (!hexdig['0']) + hexdig_init_D2A(); + nbits = fpi->nbits; + x = x0 + (nbits >> kshift); + if (nbits & kmask) + x++; + *--x = 0; + x1 = xe = x; + havedig = hd0 = i = 0; + s = *sp; + while(c = *(CONST unsigned char*)++s) { + if (!(h = hexdig[c])) { + if (c <= ' ') { + if (hd0 < havedig) { + if (x < x1 && i < 8) + L_shift(x, x1, i); + if (x <= x0) { + i = 8; + continue; + } + hd0 = havedig; + *--x = 0; + x1 = x; + i = 0; + } + continue; + } + if (/*(*/ c == ')' && havedig) { + *sp = s + 1; + break; + } + return STRTOG_NaN; + } + havedig++; + if (++i > 8) { + if (x <= x0) + continue; + i = 1; + *--x = 0; + } + *x = (*x << 4) | h & 0xf; + } + if (!havedig) + return STRTOG_NaN; + if (x < x1 && i < 8) + L_shift(x, x1, i); + if (x > x0) { + x1 = x0; + do *x1++ = *x++; + while(x <= xe); + do *x1++ = 0; + while(x1 <= xe); + } + else { + /* truncate high-order word if necessary */ + if ( (i = nbits & (ULbits-1)) !=0) + *xe &= ((ULong)0xffffffff) >> (ULbits - i); + } + for(x1 = xe;; --x1) { + if (*x1 != 0) + break; + if (x1 == x0) { + *x1 = 1; + break; + } + } + return STRTOG_NaNbits; + } |