Initial import of David Gay's gdtoa library for conversion between

strings and floating point.

1 files changed, 94 insertions, 0 deletions

diff --git a/contrib/gdtoa/g_ffmt.c b/contrib/gdtoa/g_ffmt.c
new file mode 100644
index 0000000..851394a
--- /dev/null
+++ b/contrib/gdtoa/g_ffmt.c
@@ -0,0 +1,94 @@
+/****************************************************************
+
+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
+	Bell Laboratories, Room 2C-463
+	600 Mountain Avenue
+	Murray Hill, NJ 07974-0636
+	U.S.A.
+	dmg@bell-labs.com
+ */
+
+#include "gdtoaimp.h"
+
+ char*
+#ifdef KR_headers
+g_ffmt(buf, f, ndig, bufsize) char *buf; float *f; int ndig; unsigned bufsize;
+#else
+g_ffmt(char *buf, float *f, int ndig, unsigned bufsize)
+#endif
+{
+	static FPI fpi = { 24, 1-127-24+1,  254-127-24+1, 1, 0 };
+	char *b, *s, *se;
+	ULong bits[1], *L, sign;
+	int decpt, ex, i, mode;
+
+	if (ndig < 0)
+		ndig = 0;
+	if (bufsize < ndig + 10)
+		return 0;
+
+	L = (ULong*)f;
+	sign = L[0] & 0x80000000L;
+	if ((L[0] & 0x7f800000) == 0x7f800000) {
+		/* Infinity or NaN */
+		if (L[0] & 0x7fffff) {
+			return strcp(buf, "NaN");
+			}
+		b = buf;
+		if (sign)
+			*b++ = '-';
+		return strcp(b, "Infinity");
+		}
+	if (*f == 0.) {
+		b = buf;
+#ifndef IGNORE_ZERO_SIGN
+		if (L[0] & 0x80000000L)
+			*b++ = '-';
+#endif
+		*b++ = '0';
+		*b = 0;
+		return b;
+		}
+	bits[0] = L[0] & 0x7fffff;
+	if ( (ex = (L[0] >> 23) & 0xff) !=0)
+		bits[0] |= 0x800000;
+	else
+		ex = 1;
+	ex -= 0x7f + 23;
+	mode = 2;
+	if (ndig <= 0) {
+		if (bufsize < 16)
+			return 0;
+		mode = 0;
+		}
+	i = STRTOG_Normal;
+	s = gdtoa(&fpi, ex, bits, &i, mode, ndig, &decpt, &se);
+	return g__fmt(buf, s, se, decpt, sign);
+	}