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diff --git a/libparse/ieee754io.c b/libparse/ieee754io.c
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+/*
+ * /src/NTP/ntp4-dev/libntp/ieee754io.c,v 4.12 2005/04/16 17:32:10 kardel RELEASE_20050508_A
+ *
+ * ieee754io.c,v 4.12 2005/04/16 17:32:10 kardel RELEASE_20050508_A
+ *
+ * $Created: Sun Jul 13 09:12:02 1997 $
+ *
+ * Copyright (c) 1997-2005 by Frank Kardel <kardel <AT> ntp.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the author nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdio.h>
+#include "l_stdlib.h"
+#include "ntp_stdlib.h"
+#include "ntp_fp.h"
+#include "ieee754io.h"
+
+static unsigned char get_byte (unsigned char *, offsets_t, int *);
+#ifdef __not_yet__
+static void put_byte (unsigned char *, offsets_t, int *, unsigned char);
+#endif
+
+#ifdef LIBDEBUG
+
+#include "lib_strbuf.h"
+
+static char *
+fmt_blong(
+ unsigned long val,
+ int cnt
+ )
+{
+ char *buf, *s;
+ int i = cnt;
+
+ val <<= 32 - cnt;
+ LIB_GETBUF(buf);
+ s = buf;
+
+ while (i--)
+ {
+ if (val & 0x80000000)
+ {
+ *s++ = '1';
+ }
+ else
+ {
+ *s++ = '0';
+ }
+ val <<= 1;
+ }
+ *s = '\0';
+ return buf;
+}
+
+static char *
+fmt_flt(
+ unsigned int sign,
+ unsigned long mh,
+ unsigned long ml,
+ unsigned long ch
+ )
+{
+ char *buf;
+
+ LIB_GETBUF(buf);
+ snprintf(buf, LIB_BUFLENGTH, "%c %s %s %s", sign ? '-' : '+',
+ fmt_blong(ch, 11),
+ fmt_blong(mh, 20),
+ fmt_blong(ml, 32));
+
+ return buf;
+}
+
+static char *
+fmt_hex(
+ unsigned char *bufp,
+ int length
+ )
+{
+ char * buf;
+ char hex[4];
+ int i;
+
+ LIB_GETBUF(buf);
+ buf[0] = '\0';
+ for (i = 0; i < length; i++) {
+ snprintf(hex, sizeof(hex), "%02x", bufp[i]);
+ strlcat(buf, hex, LIB_BUFLENGTH);
+ }
+
+ return buf;
+}
+
+#endif
+
+static unsigned char
+get_byte(
+ unsigned char *bufp,
+ offsets_t offset,
+ int *fieldindex
+ )
+{
+ unsigned char val;
+
+ val = *(bufp + offset[*fieldindex]);
+#ifdef LIBDEBUG
+ if (debug > 4)
+ printf("fetchieee754: getbyte(0x%08x, %d) = 0x%02x\n", (unsigned int)(bufp)+offset[*fieldindex], *fieldindex, val);
+#endif
+ (*fieldindex)++;
+ return val;
+}
+
+#ifdef __not_yet__
+static void
+put_byte(
+ unsigned char *bufp,
+ offsets_t offsets,
+ int *fieldindex,
+ unsigned char val
+ )
+{
+ *(bufp + offsets[*fieldindex]) = val;
+ (*fieldindex)++;
+}
+#endif
+
+/*
+ * make conversions to and from external IEEE754 formats and internal
+ * NTP FP format.
+ */
+int
+fetch_ieee754(
+ unsigned char **buffpp,
+ int size,
+ l_fp *lfpp,
+ offsets_t offsets
+ )
+{
+ unsigned char *bufp = *buffpp;
+ unsigned int sign;
+ unsigned int bias;
+ unsigned int maxexp;
+ int mbits;
+ u_long mantissa_low;
+ u_long mantissa_high;
+ u_long characteristic;
+ long exponent;
+#ifdef LIBDEBUG
+ int length;
+#endif
+ unsigned char val;
+ int fieldindex = 0;
+
+ switch (size)
+ {
+ case IEEE_DOUBLE:
+#ifdef LIBDEBUG
+ length = 8;
+#endif
+ mbits = 52;
+ bias = 1023;
+ maxexp = 2047;
+ break;
+
+ case IEEE_SINGLE:
+#ifdef LIBDEBUG
+ length = 4;
+#endif
+ mbits = 23;
+ bias = 127;
+ maxexp = 255;
+ break;
+
+ default:
+ return IEEE_BADCALL;
+ }
+
+ val = get_byte(bufp, offsets, &fieldindex); /* fetch sign byte & first part of characteristic */
+
+ sign = (val & 0x80) != 0;
+ characteristic = (val & 0x7F);
+
+ val = get_byte(bufp, offsets, &fieldindex); /* fetch rest of characteristic and start of mantissa */
+
+ switch (size)
+ {
+ case IEEE_SINGLE:
+ characteristic <<= 1;
+ characteristic |= (val & 0x80) != 0; /* grab last characteristic bit */
+
+ mantissa_high = 0;
+
+ mantissa_low = (val &0x7F) << 16;
+ mantissa_low |= (u_long)get_byte(bufp, offsets, &fieldindex) << 8;
+ mantissa_low |= get_byte(bufp, offsets, &fieldindex);
+ break;
+
+ case IEEE_DOUBLE:
+ characteristic <<= 4;
+ characteristic |= (val & 0xF0) >> 4; /* grab lower characteristic bits */
+
+ mantissa_high = (val & 0x0F) << 16;
+ mantissa_high |= (u_long)get_byte(bufp, offsets, &fieldindex) << 8;
+ mantissa_high |= get_byte(bufp, offsets, &fieldindex);
+
+ mantissa_low = (u_long)get_byte(bufp, offsets, &fieldindex) << 24;
+ mantissa_low |= (u_long)get_byte(bufp, offsets, &fieldindex) << 16;
+ mantissa_low |= (u_long)get_byte(bufp, offsets, &fieldindex) << 8;
+ mantissa_low |= get_byte(bufp, offsets, &fieldindex);
+ break;
+
+ default:
+ return IEEE_BADCALL;
+ }
+#ifdef LIBDEBUG
+ if (debug > 4)
+ {
+ double d;
+ float f;
+
+ if (size == IEEE_SINGLE)
+ {
+ int i;
+
+ for (i = 0; i < length; i++)
+ {
+ *((unsigned char *)(&f)+i) = *(*buffpp + offsets[i]);
+ }
+ d = f;
+ }
+ else
+ {
+ int i;
+
+ for (i = 0; i < length; i++)
+ {
+ *((unsigned char *)(&d)+i) = *(*buffpp + offsets[i]);
+ }
+ }
+
+ printf("fetchieee754: FP: %s -> %s -> %e(=%s)\n", fmt_hex(*buffpp, length),
+ fmt_flt(sign, mantissa_high, mantissa_low, characteristic),
+ d, fmt_hex((unsigned char *)&d, length));
+ }
+#endif
+
+ *buffpp += fieldindex;
+
+ /*
+ * detect funny numbers
+ */
+ if (characteristic == maxexp)
+ {
+ /*
+ * NaN or Infinity
+ */
+ if (mantissa_low || mantissa_high)
+ {
+ /*
+ * NaN
+ */
+ return IEEE_NAN;
+ }
+ else
+ {
+ /*
+ * +Inf or -Inf
+ */
+ return sign ? IEEE_NEGINFINITY : IEEE_POSINFINITY;
+ }
+ }
+ else
+ {
+ /*
+ * collect real numbers
+ */
+
+ L_CLR(lfpp);
+
+ /*
+ * check for overflows
+ */
+ exponent = characteristic - bias;
+
+ if (exponent > 31) /* sorry - hardcoded */
+ {
+ /*
+ * overflow only in respect to NTP-FP representation
+ */
+ return sign ? IEEE_NEGOVERFLOW : IEEE_POSOVERFLOW;
+ }
+ else
+ {
+ int frac_offset; /* where the fraction starts */
+
+ frac_offset = mbits - exponent;
+
+ if (characteristic == 0)
+ {
+ /*
+ * de-normalized or tiny number - fits only as 0
+ */
+ return IEEE_OK;
+ }
+ else
+ {
+ /*
+ * adjust for implied 1
+ */
+ if (mbits > 31)
+ mantissa_high |= 1 << (mbits - 32);
+ else
+ mantissa_low |= 1 << mbits;
+
+ /*
+ * take mantissa apart - if only all machine would support
+ * 64 bit operations 8-(
+ */
+ if (frac_offset > mbits)
+ {
+ lfpp->l_ui = 0; /* only fractional number */
+ frac_offset -= mbits + 1; /* will now contain right shift count - 1*/
+ if (mbits > 31)
+ {
+ lfpp->l_uf = mantissa_high << (63 - mbits);
+ lfpp->l_uf |= mantissa_low >> (mbits - 33);
+ lfpp->l_uf >>= frac_offset;
+ }
+ else
+ {
+ lfpp->l_uf = mantissa_low >> frac_offset;
+ }
+ }
+ else
+ {
+ if (frac_offset > 32)
+ {
+ /*
+ * must split in high word
+ */
+ lfpp->l_ui = mantissa_high >> (frac_offset - 32);
+ lfpp->l_uf = (mantissa_high & ((1 << (frac_offset - 32)) - 1)) << (64 - frac_offset);
+ lfpp->l_uf |= mantissa_low >> (frac_offset - 32);
+ }
+ else
+ {
+ /*
+ * must split in low word
+ */
+ lfpp->l_ui = mantissa_high << (32 - frac_offset);
+ lfpp->l_ui |= (mantissa_low >> frac_offset) & ((1 << (32 - frac_offset)) - 1);
+ lfpp->l_uf = (mantissa_low & ((1 << frac_offset) - 1)) << (32 - frac_offset);
+ }
+ }
+
+ /*
+ * adjust for sign
+ */
+ if (sign)
+ {
+ L_NEG(lfpp);
+ }
+
+ return IEEE_OK;
+ }
+ }
+ }
+}
+
+int
+put_ieee754(
+ unsigned char **bufpp,
+ int size,
+ l_fp *lfpp,
+ offsets_t offsets
+ )
+{
+ l_fp outlfp;
+#ifdef LIBDEBUG
+ unsigned int sign;
+ unsigned int bias;
+#endif
+/*unsigned int maxexp;*/
+ int mbits;
+ int msb;
+ u_long mantissa_low = 0;
+ u_long mantissa_high = 0;
+#ifdef LIBDEBUG
+ u_long characteristic = 0;
+ long exponent;
+#endif
+/*int length;*/
+ unsigned long mask;
+
+ outlfp = *lfpp;
+
+ switch (size)
+ {
+ case IEEE_DOUBLE:
+ /*length = 8;*/
+ mbits = 52;
+#ifdef LIBDEBUG
+ bias = 1023;
+#endif
+ /*maxexp = 2047;*/
+ break;
+
+ case IEEE_SINGLE:
+ /*length = 4;*/
+ mbits = 23;
+#ifdef LIBDEBUG
+ bias = 127;
+#endif
+ /*maxexp = 255;*/
+ break;
+
+ default:
+ return IEEE_BADCALL;
+ }
+
+ /*
+ * find sign
+ */
+ if (L_ISNEG(&outlfp))
+ {
+ L_NEG(&outlfp);
+#ifdef LIBDEBUG
+ sign = 1;
+#endif
+ }
+ else
+ {
+#ifdef LIBDEBUG
+ sign = 0;
+#endif
+ }
+
+ if (L_ISZERO(&outlfp))
+ {
+#ifdef LIBDEBUG
+ exponent = mantissa_high = mantissa_low = 0; /* true zero */
+#endif
+ }
+ else
+ {
+ /*
+ * find number of significant integer bits
+ */
+ mask = 0x80000000;
+ if (outlfp.l_ui)
+ {
+ msb = 63;
+ while (mask && ((outlfp.l_ui & mask) == 0))
+ {
+ mask >>= 1;
+ msb--;
+ }
+ }
+ else
+ {
+ msb = 31;
+ while (mask && ((outlfp.l_uf & mask) == 0))
+ {
+ mask >>= 1;
+ msb--;
+ }
+ }
+
+ switch (size)
+ {
+ case IEEE_SINGLE:
+ mantissa_high = 0;
+ if (msb >= 32)
+ {
+ mantissa_low = (outlfp.l_ui & ((1 << (msb - 32)) - 1)) << (mbits - (msb - 32));
+ mantissa_low |= outlfp.l_uf >> (mbits - (msb - 32));
+ }
+ else
+ {
+ mantissa_low = (outlfp.l_uf << (mbits - msb)) & ((1 << mbits) - 1);
+ }
+ break;
+
+ case IEEE_DOUBLE:
+ if (msb >= 32)
+ {
+ mantissa_high = (outlfp.l_ui << (mbits - msb)) & ((1 << (mbits - 32)) - 1);
+ mantissa_high |= outlfp.l_uf >> (32 - (mbits - msb));
+ mantissa_low = (outlfp.l_ui & ((1 << (msb - mbits)) - 1)) << (32 - (msb - mbits));
+ mantissa_low |= outlfp.l_uf >> (msb - mbits);
+ }
+ else
+ {
+ mantissa_high = outlfp.l_uf << (mbits - 32 - msb);
+ mantissa_low = outlfp.l_uf << (mbits - 32);
+ }
+ }
+
+#ifdef LIBDEBUG
+ exponent = msb - 32;
+ characteristic = exponent + bias;
+
+ if (debug > 4)
+ printf("FP: %s\n", fmt_flt(sign, mantissa_high, mantissa_low, characteristic));
+#endif
+ }
+ return IEEE_OK;
+}
+
+
+#if defined(DEBUG) && defined(LIBDEBUG)
+int main(
+ int argc,
+ char **argv
+ )
+{
+ static offsets_t native_off = { 0, 1, 2, 3, 4, 5, 6, 7 };
+ double f = 1.0;
+ double *f_p = &f;
+ l_fp fp;
+
+ if (argc == 2)
+ {
+ if (sscanf(argv[1], "%lf", &f) != 1)
+ {
+ printf("cannot convert %s to a float\n", argv[1]);
+ return 1;
+ }
+ }
+
+ printf("double: %s %s\n", fmt_blong(*(unsigned long *)&f, 32), fmt_blong(*(unsigned long *)((char *)(&f)+4), 32));
+ printf("fetch from %f = %d\n", f, fetch_ieee754((void *)&f_p, IEEE_DOUBLE, &fp, native_off));
+ printf("fp [%s %s] = %s\n", fmt_blong(fp.l_ui, 32), fmt_blong(fp.l_uf, 32), mfptoa(fp.l_ui, fp.l_uf, 15));
+ f_p = &f;
+ put_ieee754((void *)&f_p, IEEE_DOUBLE, &fp, native_off);
+
+ return 0;
+}
+
+#endif
+/*
+ * History:
+ *
+ * ieee754io.c,v
+ * Revision 4.12 2005/04/16 17:32:10 kardel
+ * update copyright
+ *
+ * Revision 4.11 2004/11/14 15:29:41 kardel
+ * support PPSAPI, upgrade Copyright to Berkeley style
+ *
+ * Revision 4.8 1999/02/21 12:17:36 kardel
+ * 4.91f reconcilation
+ *
+ * Revision 4.7 1999/02/21 11:26:03 kardel
+ * renamed index to fieldindex to avoid index() name clash
+ *
+ * Revision 4.6 1998/11/15 20:27:52 kardel
+ * Release 4.0.73e13 reconcilation
+ *
+ * Revision 4.5 1998/08/16 19:01:51 kardel
+ * debug information only compile for LIBDEBUG case
+ *
+ * Revision 4.4 1998/08/09 09:39:28 kardel
+ * Release 4.0.73e2 reconcilation
+ *
+ * Revision 4.3 1998/06/13 11:56:19 kardel
+ * disabled putbute() for the time being
+ *
+ * Revision 4.2 1998/06/12 15:16:58 kardel
+ * ansi2knr compatibility
+ *
+ * Revision 4.1 1998/05/24 07:59:56 kardel
+ * conditional debug support
+ *
+ * Revision 4.0 1998/04/10 19:46:29 kardel
+ * Start 4.0 release version numbering
+ *
+ * Revision 1.1 1998/04/10 19:27:46 kardel
+ * initial NTP VERSION 4 integration of PARSE with GPS166 binary support
+ *
+ * Revision 1.1 1997/10/06 21:05:45 kardel
+ * new parse structure
+ *
+ */
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