minix/lib/libc/gdtoa/gethex.c
Ben Gras 2fe8fb192f Full switch to clang/ELF. Drop ack. Simplify.
There is important information about booting non-ack images in
docs/UPDATING. ack/aout-format images can't be built any more, and
booting clang/ELF-format ones is a little different. Updating to the
new boot monitor is recommended.

Changes in this commit:

	. drop boot monitor -> allowing dropping ack support
	. facility to copy ELF boot files to /boot so that old boot monitor
	  can still boot fairly easily, see UPDATING
	. no more ack-format libraries -> single-case libraries
	. some cleanup of OBJECT_FMT, COMPILER_TYPE, etc cases
	. drop several ack toolchain commands, but not all support
	  commands (e.g. aal is gone but acksize is not yet).
	. a few libc files moved to netbsd libc dir
	. new /bin/date as minix date used code in libc/
	. test compile fix
	. harmonize includes
	. /usr/lib is no longer special: without ack, /usr/lib plays no
	  kind of special bootstrapping role any more and bootstrapping
	  is done exclusively through packages, so releases depend even
	  less on the state of the machine making them now.
	. rename nbsd_lib* to lib*
	. reduce mtree
2012-02-14 14:52:02 +01:00

253 lines
5.3 KiB
C

/* $NetBSD: gethex.c,v 1.4 2008/03/21 23:13:48 christos Exp $ */
/****************************************************************
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 (dmg at acm dot org,
* with " at " changed at "@" and " dot " changed to "."). */
#include "gdtoaimp.h"
#ifdef USE_LOCALE
#include "locale.h"
#endif
int
#ifdef KR_headers
gethex(sp, fpi, expt, bp, sign)
CONST char **sp; CONST FPI *fpi; Long *expt; Bigint **bp; int sign;
#else
gethex( CONST char **sp, CONST FPI *fpi, Long *expt, Bigint **bp, int sign)
#endif
{
Bigint *b;
CONST unsigned char *decpt, *s0, *s, *s1;
int esign, havedig, irv, k, n, nbits, up, zret;
ULong L, lostbits, *x;
Long e, e1;
#ifdef USE_LOCALE
unsigned char decimalpoint = *localeconv()->decimal_point;
#else
#define decimalpoint '.'
#endif
if (!hexdig['0'])
hexdig_init_D2A();
havedig = 0;
s0 = *(CONST unsigned char **)sp + 2;
while(s0[havedig] == '0')
havedig++;
s0 += havedig;
s = s0;
decpt = 0;
zret = 0;
e = 0;
if (!hexdig[*s]) {
zret = 1;
if (*s != decimalpoint)
goto pcheck;
decpt = ++s;
if (!hexdig[*s])
goto pcheck;
while(*s == '0')
s++;
if (hexdig[*s])
zret = 0;
havedig = 1;
s0 = s;
}
while(hexdig[*s])
s++;
if (*s == decimalpoint && !decpt) {
decpt = ++s;
while(hexdig[*s])
s++;
}
if (decpt)
e = -(((Long)(s-decpt)) << 2);
pcheck:
s1 = s;
switch(*s) {
case 'p':
case 'P':
esign = 0;
switch(*++s) {
case '-':
esign = 1;
/* FALLTHROUGH */
case '+':
s++;
}
if ((n = hexdig[*s]) == 0 || n > 0x19) {
s = s1;
break;
}
e1 = n - 0x10;
while((n = hexdig[*++s]) !=0 && n <= 0x19)
e1 = 10*e1 + n - 0x10;
if (esign)
e1 = -e1;
e += e1;
}
*sp = __UNCONST(s);
if (zret)
return havedig ? STRTOG_Zero : STRTOG_NoNumber;
n = s1 - s0 - 1;
for(k = 0; n > 7; n = (unsigned int)n >> 1)
k++;
b = Balloc(k);
if (b == NULL)
return STRTOG_NoMemory;
x = b->x;
n = 0;
L = 0;
while(s1 > s0) {
if (*--s1 == decimalpoint)
continue;
if (n == 32) {
*x++ = L;
L = 0;
n = 0;
}
L |= (hexdig[*s1] & 0x0f) << n;
n += 4;
}
*x++ = L;
b->wds = n = x - b->x;
n = 32*n - hi0bits(L);
nbits = fpi->nbits;
lostbits = 0;
x = b->x;
if (n > nbits) {
n -= nbits;
if (any_on(b,n)) {
lostbits = 1;
k = n - 1;
if (x[(unsigned int)k>>kshift] & 1 << (k & kmask)) {
lostbits = 2;
if (k > 1 && any_on(b,k-1))
lostbits = 3;
}
}
rshift(b, n);
e += n;
}
else if (n < nbits) {
n = nbits - n;
b = lshift(b, n);
if (b == NULL)
return STRTOG_NoMemory;
e -= n;
x = b->x;
}
if (e > fpi->emax) {
ovfl:
Bfree(b);
*bp = 0;
return STRTOG_Infinite | STRTOG_Overflow | STRTOG_Inexhi;
}
irv = STRTOG_Normal;
if (e < fpi->emin) {
irv = STRTOG_Denormal;
n = fpi->emin - e;
if (n >= nbits) {
switch (fpi->rounding) {
case FPI_Round_near:
if (n == nbits && (n < 2 || any_on(b,n-1)))
goto one_bit;
break;
case FPI_Round_up:
if (!sign)
goto one_bit;
break;
case FPI_Round_down:
if (sign) {
one_bit:
*expt = fpi->emin;
x[0] = b->wds = 1;
*bp = b;
return STRTOG_Denormal | STRTOG_Inexhi
| STRTOG_Underflow;
}
}
Bfree(b);
*bp = 0;
return STRTOG_Zero | STRTOG_Inexlo | STRTOG_Underflow;
}
k = n - 1;
if (lostbits)
lostbits = 1;
else if (k > 0)
lostbits = any_on(b,k);
if (x[(unsigned int)k>>kshift] & 1 << (k & kmask))
lostbits |= 2;
nbits -= n;
rshift(b,n);
e = fpi->emin;
}
if (lostbits) {
up = 0;
switch(fpi->rounding) {
case FPI_Round_zero:
break;
case FPI_Round_near:
if (lostbits & 2
&& (lostbits & 1) | (x[0] & 1))
up = 1;
break;
case FPI_Round_up:
up = 1 - sign;
break;
case FPI_Round_down:
up = sign;
}
if (up) {
k = b->wds;
b = increment(b);
x = b->x;
if (irv == STRTOG_Denormal) {
if (nbits == fpi->nbits - 1
&& x[(unsigned int)nbits >> kshift] & 1 << (nbits & kmask))
irv = STRTOG_Normal;
}
else if (b->wds > k
|| ((n = nbits & kmask) !=0
&& hi0bits(x[k-1]) < 32-n)) {
rshift(b,1);
if (++e > fpi->emax)
goto ovfl;
}
irv |= STRTOG_Inexhi;
}
else
irv |= STRTOG_Inexlo;
}
*bp = b;
*expt = e;
return irv;
}