hexnan.c revision 165743
1/**************************************************************** 2 3The author of this software is David M. Gay. 4 5Copyright (C) 2000 by Lucent Technologies 6All Rights Reserved 7 8Permission to use, copy, modify, and distribute this software and 9its documentation for any purpose and without fee is hereby 10granted, provided that the above copyright notice appear in all 11copies and that both that the copyright notice and this 12permission notice and warranty disclaimer appear in supporting 13documentation, and that the name of Lucent or any of its entities 14not be used in advertising or publicity pertaining to 15distribution of the software without specific, written prior 16permission. 17 18LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 19INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. 20IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY 21SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 22WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER 23IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, 24ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF 25THIS SOFTWARE. 26 27****************************************************************/ 28 29/* Please send bug reports to David M. Gay (dmg at acm dot org, 30 * with " at " changed at "@" and " dot " changed to "."). */ 31 32#include "gdtoaimp.h" 33 34 static void 35#ifdef KR_headers 36L_shift(x, x1, i) ULong *x; ULong *x1; int i; 37#else 38L_shift(ULong *x, ULong *x1, int i) 39#endif 40{ 41 int j; 42 43 i = 8 - i; 44 i <<= 2; 45 j = ULbits - i; 46 do { 47 *x |= x[1] << j; 48 x[1] >>= i; 49 } while(++x < x1); 50 } 51 52 int 53#ifdef KR_headers 54hexnan(sp, fpi, x0) 55 CONST char **sp; FPI *fpi; ULong *x0; 56#else 57hexnan( CONST char **sp, FPI *fpi, ULong *x0) 58#endif 59{ 60 ULong c, h, *x, *x1, *xe; 61 CONST char *s; 62 int havedig, hd0, i, nbits; 63 64 if (!hexdig['0']) 65 hexdig_init_D2A(); 66 nbits = fpi->nbits; 67 x = x0 + (nbits >> kshift); 68 if (nbits & kmask) 69 x++; 70 *--x = 0; 71 x1 = xe = x; 72 havedig = hd0 = i = 0; 73 s = *sp; 74 while(c = *(CONST unsigned char*)++s) { 75 if (!(h = hexdig[c])) { 76 if (c <= ' ') { 77 if (hd0 < havedig) { 78 if (x < x1 && i < 8) 79 L_shift(x, x1, i); 80 if (x <= x0) { 81 i = 8; 82 continue; 83 } 84 hd0 = havedig; 85 *--x = 0; 86 x1 = x; 87 i = 0; 88 } 89 continue; 90 } 91 if (/*(*/ c == ')' && havedig) { 92 *sp = s + 1; 93 break; 94 } 95 return STRTOG_NaN; 96 } 97 havedig++; 98 if (++i > 8) { 99 if (x <= x0) 100 continue; 101 i = 1; 102 *--x = 0; 103 } 104 *x = (*x << 4) | h & 0xf; 105 } 106 if (!havedig) 107 return STRTOG_NaN; 108 if (x < x1 && i < 8) 109 L_shift(x, x1, i); 110 if (x > x0) { 111 x1 = x0; 112 do *x1++ = *x++; 113 while(x <= xe); 114 do *x1++ = 0; 115 while(x1 <= xe); 116 } 117 else { 118 /* truncate high-order word if necessary */ 119 if ( (i = nbits & (ULbits-1)) !=0) 120 *xe &= ((ULong)0xffffffff) >> (ULbits - i); 121 } 122 for(x1 = xe;; --x1) { 123 if (*x1 != 0) 124 break; 125 if (x1 == x0) { 126 *x1 = 1; 127 break; 128 } 129 } 130 return STRTOG_NaNbits; 131 } 132