1 /**************************************************************** 2 3 The author of this software is David M. Gay. 4 5 Copyright (C) 1998 by Lucent Technologies 6 All Rights Reserved 7 8 Permission to use, copy, modify, and distribute this software and 9 its documentation for any purpose and without fee is hereby 10 granted, provided that the above copyright notice appear in all 11 copies and that both that the copyright notice and this 12 permission notice and warranty disclaimer appear in supporting 13 documentation, and that the name of Lucent or any of its entities 14 not be used in advertising or publicity pertaining to 15 distribution of the software without specific, written prior 16 permission. 17 18 LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 19 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. 20 IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY 21 SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 22 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER 23 IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, 24 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF 25 THIS 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 char* 35 #ifdef KR_headers 36 g_dfmt(buf, d, ndig, bufsize) char *buf; double *d; int ndig; size_t bufsize; 37 #else 38 g_dfmt(char *buf, double *d, int ndig, size_t bufsize) 39 #endif 40 { 41 static FPI fpi0 = { 53, 1-1023-53+1, 2046-1023-53+1, 1, 0 }; 42 char *b, *s, *se; 43 ULong bits[2], *L, sign; 44 int decpt, ex, i, mode; 45 #ifdef Honor_FLT_ROUNDS 46 #include "gdtoa_fltrnds.h" 47 #else 48 #define fpi &fpi0 49 #endif 50 51 if (ndig < 0) 52 ndig = 0; 53 if (bufsize < ndig + 10) 54 return 0; 55 56 L = (ULong*)d; 57 sign = L[_0] & 0x80000000L; 58 if ((L[_0] & 0x7ff00000) == 0x7ff00000) { 59 /* Infinity or NaN */ 60 if (bufsize < 10) 61 return 0; 62 if (L[_0] & 0xfffff || L[_1]) { 63 return strcp(buf, "NaN"); 64 } 65 b = buf; 66 if (sign) 67 *b++ = '-'; 68 return strcp(b, "Infinity"); 69 } 70 if (L[_1] == 0 && (L[_0] ^ sign) == 0 /*d == 0.*/) { 71 b = buf; 72 #ifndef IGNORE_ZERO_SIGN 73 if (L[_0] & 0x80000000L) 74 *b++ = '-'; 75 #endif 76 *b++ = '0'; 77 *b = 0; 78 return b; 79 } 80 bits[0] = L[_1]; 81 bits[1] = L[_0] & 0xfffff; 82 if ( (ex = (L[_0] >> 20) & 0x7ff) !=0) 83 bits[1] |= 0x100000; 84 else 85 ex = 1; 86 ex -= 0x3ff + 52; 87 mode = 2; 88 if (ndig <= 0) 89 mode = 0; 90 i = STRTOG_Normal; 91 if (sign) 92 i = STRTOG_Normal | STRTOG_Neg; 93 s = gdtoa(fpi, ex, bits, &i, mode, ndig, &decpt, &se); 94 return g__fmt(buf, s, se, decpt, sign, bufsize); 95 } 96