diff options
Diffstat (limited to 'StdLib/LibC/gdtoa/gethex.c')
| -rw-r--r-- | StdLib/LibC/gdtoa/gethex.c | 249 |
1 files changed, 249 insertions, 0 deletions
diff --git a/StdLib/LibC/gdtoa/gethex.c b/StdLib/LibC/gdtoa/gethex.c new file mode 100644 index 0000000000..02920e748c --- /dev/null +++ b/StdLib/LibC/gdtoa/gethex.c @@ -0,0 +1,249 @@ +/* $NetBSD: gethex.c,v 1.3.14.1 2008/04/08 21:10:55 jdc 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 <LibConfig.h>
+
+#include "gdtoaimp.h"
+
+#ifdef USE_LOCALE
+#include "locale.h"
+#endif
+
+ int
+gethex( CONST char **sp, CONST FPI *fpi, Long *expt, Bigint **bp, int sign)
+{
+ 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 = (int)(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 = (int)(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;
+ }
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