xref: /onnv-gate/usr/src/lib/libc/port/i18n/wstod.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24*0Sstevel@tonic-gate  * Use is subject to license terms.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
28*0Sstevel@tonic-gate 
29*0Sstevel@tonic-gate /*	Copyright (c) 1988 AT&T	*/
30*0Sstevel@tonic-gate /*	  All Rights Reserved  	*/
31*0Sstevel@tonic-gate 
32*0Sstevel@tonic-gate 
33*0Sstevel@tonic-gate /*
34*0Sstevel@tonic-gate  * This file is based on /usr/src/lib/libc/port/gen/strtod.c and
35*0Sstevel@tonic-gate  * /usr/src/lib/libc/sparc/fp/string_decim.c
36*0Sstevel@tonic-gate  */
37*0Sstevel@tonic-gate 
38*0Sstevel@tonic-gate #pragma weak wcstod = _wcstod
39*0Sstevel@tonic-gate #pragma weak wstod = _wstod
40*0Sstevel@tonic-gate 
41*0Sstevel@tonic-gate #include "synonyms.h"
42*0Sstevel@tonic-gate #include <errno.h>
43*0Sstevel@tonic-gate #include <stdio.h>
44*0Sstevel@tonic-gate #include <values.h>
45*0Sstevel@tonic-gate #include <floatingpoint.h>
46*0Sstevel@tonic-gate #include <stddef.h>
47*0Sstevel@tonic-gate #include <wctype.h>
48*0Sstevel@tonic-gate #include "base_conversion.h"	/* from usr/src/lib/libc/inc */
49*0Sstevel@tonic-gate #include <locale.h>
50*0Sstevel@tonic-gate #include "libc.h"
51*0Sstevel@tonic-gate #include "xpg6.h"
52*0Sstevel@tonic-gate 
53*0Sstevel@tonic-gate static void wstring_to_decimal(const wchar_t **, int, decimal_record *, int *);
54*0Sstevel@tonic-gate 
55*0Sstevel@tonic-gate double
56*0Sstevel@tonic-gate _wcstod(const wchar_t *cp, wchar_t **ptr)
57*0Sstevel@tonic-gate {
58*0Sstevel@tonic-gate 	double		x;
59*0Sstevel@tonic-gate 	decimal_mode	mr;
60*0Sstevel@tonic-gate 	decimal_record	dr;
61*0Sstevel@tonic-gate 	fp_exception_field_type fs;
62*0Sstevel@tonic-gate 	int 		form;
63*0Sstevel@tonic-gate 
64*0Sstevel@tonic-gate 	wstring_to_decimal(&cp, __xpg6 & _C99SUSv3_recognize_hexfp, &dr, &form);
65*0Sstevel@tonic-gate 	if (ptr != NULL)
66*0Sstevel@tonic-gate 		*ptr = (wchar_t *)cp;
67*0Sstevel@tonic-gate 	if (form == 0)
68*0Sstevel@tonic-gate 		return (0.0);	/* Shameful kluge for SVID's sake. */
69*0Sstevel@tonic-gate #if defined(__i386) || defined(__amd64)
70*0Sstevel@tonic-gate 	mr.rd = __xgetRD();
71*0Sstevel@tonic-gate #elif defined(__sparc)
72*0Sstevel@tonic-gate 	mr.rd = _QgetRD();
73*0Sstevel@tonic-gate #else
74*0Sstevel@tonic-gate #error Unknown architecture!
75*0Sstevel@tonic-gate #endif
76*0Sstevel@tonic-gate 	if (form < 0)
77*0Sstevel@tonic-gate 		__hex_to_double(&dr, mr.rd, &x, &fs);
78*0Sstevel@tonic-gate 	else
79*0Sstevel@tonic-gate 		decimal_to_double(&x, &mr, &dr, &fs);
80*0Sstevel@tonic-gate 	if (fs & ((1 << fp_overflow) | (1 << fp_underflow)))
81*0Sstevel@tonic-gate 		errno = ERANGE;
82*0Sstevel@tonic-gate 	return (x);
83*0Sstevel@tonic-gate }
84*0Sstevel@tonic-gate 
85*0Sstevel@tonic-gate float
86*0Sstevel@tonic-gate wcstof(const wchar_t *cp, wchar_t **ptr)
87*0Sstevel@tonic-gate {
88*0Sstevel@tonic-gate 	float		x;
89*0Sstevel@tonic-gate 	decimal_mode	mr;
90*0Sstevel@tonic-gate 	decimal_record	dr;
91*0Sstevel@tonic-gate 	fp_exception_field_type fs;
92*0Sstevel@tonic-gate 	int		form;
93*0Sstevel@tonic-gate 
94*0Sstevel@tonic-gate 	wstring_to_decimal(&cp, 1, &dr, &form);
95*0Sstevel@tonic-gate 	if (ptr != NULL)
96*0Sstevel@tonic-gate 		*ptr = (wchar_t *)cp;
97*0Sstevel@tonic-gate 	if (form == 0)
98*0Sstevel@tonic-gate 		return (0.0f);
99*0Sstevel@tonic-gate #if defined(__i386) || defined(__amd64)
100*0Sstevel@tonic-gate 	mr.rd = __xgetRD();
101*0Sstevel@tonic-gate #elif defined(__sparc)
102*0Sstevel@tonic-gate 	mr.rd = _QgetRD();
103*0Sstevel@tonic-gate #else
104*0Sstevel@tonic-gate #error Unknown architecture!
105*0Sstevel@tonic-gate #endif
106*0Sstevel@tonic-gate 	if (form < 0)
107*0Sstevel@tonic-gate 		__hex_to_single(&dr, mr.rd, &x, &fs);
108*0Sstevel@tonic-gate 	else
109*0Sstevel@tonic-gate 		decimal_to_single(&x, &mr, &dr, &fs);
110*0Sstevel@tonic-gate 	if (fs & ((1 << fp_overflow) | (1 << fp_underflow)))
111*0Sstevel@tonic-gate 		errno = ERANGE;
112*0Sstevel@tonic-gate 	return (x);
113*0Sstevel@tonic-gate }
114*0Sstevel@tonic-gate 
115*0Sstevel@tonic-gate long double
116*0Sstevel@tonic-gate wcstold(const wchar_t *cp, wchar_t **ptr)
117*0Sstevel@tonic-gate {
118*0Sstevel@tonic-gate 	long double	x;
119*0Sstevel@tonic-gate 	decimal_mode	mr;
120*0Sstevel@tonic-gate 	decimal_record	dr;
121*0Sstevel@tonic-gate 	fp_exception_field_type fs;
122*0Sstevel@tonic-gate 	int		form;
123*0Sstevel@tonic-gate 
124*0Sstevel@tonic-gate 	wstring_to_decimal(&cp, 1, &dr, &form);
125*0Sstevel@tonic-gate 	if (ptr != NULL)
126*0Sstevel@tonic-gate 		*ptr = (wchar_t *)cp;
127*0Sstevel@tonic-gate 	if (form == 0)
128*0Sstevel@tonic-gate 		return (0.0L);
129*0Sstevel@tonic-gate #if defined(__i386) || defined(__amd64)
130*0Sstevel@tonic-gate 	mr.rd = __xgetRD();
131*0Sstevel@tonic-gate 	if (form < 0)
132*0Sstevel@tonic-gate 		__hex_to_extended(&dr, mr.rd, (extended *)&x, &fs);
133*0Sstevel@tonic-gate 	else
134*0Sstevel@tonic-gate 		decimal_to_extended((extended *)&x, &mr, &dr, &fs);
135*0Sstevel@tonic-gate #elif defined(__sparc)
136*0Sstevel@tonic-gate 	mr.rd = _QgetRD();
137*0Sstevel@tonic-gate 	if (form < 0)
138*0Sstevel@tonic-gate 		__hex_to_quadruple(&dr, mr.rd, &x, &fs);
139*0Sstevel@tonic-gate 	else
140*0Sstevel@tonic-gate 		decimal_to_quadruple(&x, &mr, &dr, &fs);
141*0Sstevel@tonic-gate #else
142*0Sstevel@tonic-gate #error Unknown architecture!
143*0Sstevel@tonic-gate #endif
144*0Sstevel@tonic-gate 	if (fs & ((1 << fp_overflow) | (1 << fp_underflow)))
145*0Sstevel@tonic-gate 		errno = ERANGE;
146*0Sstevel@tonic-gate 	return (x);
147*0Sstevel@tonic-gate }
148*0Sstevel@tonic-gate 
149*0Sstevel@tonic-gate double
150*0Sstevel@tonic-gate _wstod(const wchar_t *cp, wchar_t **ptr)
151*0Sstevel@tonic-gate {
152*0Sstevel@tonic-gate 	return (_wcstod(cp, ptr));
153*0Sstevel@tonic-gate }
154*0Sstevel@tonic-gate 
155*0Sstevel@tonic-gate static const char *infstring = "INFINITY";
156*0Sstevel@tonic-gate static const char *nanstring = "NAN";
157*0Sstevel@tonic-gate 
158*0Sstevel@tonic-gate /*
159*0Sstevel@tonic-gate  * The following macro is applied to wchar_t arguments solely for the
160*0Sstevel@tonic-gate  * purpose of comparing the result with one of the characters in the
161*0Sstevel@tonic-gate  * strings above.
162*0Sstevel@tonic-gate  */
163*0Sstevel@tonic-gate #define	UCASE(c)	(((L'a' <= c) && (c <= L'z'))? c - 32 : c)
164*0Sstevel@tonic-gate 
165*0Sstevel@tonic-gate /*
166*0Sstevel@tonic-gate  * The following macro yields an expression that is true whenever
167*0Sstevel@tonic-gate  * the argument is a valid nonzero digit for the form being parsed.
168*0Sstevel@tonic-gate  */
169*0Sstevel@tonic-gate #define	NZDIGIT(c)	((L'1' <= c && c <= L'9') || (form < 0 && \
170*0Sstevel@tonic-gate 			((L'a' <= c && c <= L'f') || (L'A' <= c && c <= L'F'))))
171*0Sstevel@tonic-gate 
172*0Sstevel@tonic-gate /*
173*0Sstevel@tonic-gate  * wstring_to_decimal is modelled on string_to_decimal, the majority
174*0Sstevel@tonic-gate  * of which can be found in the common file char_to_decimal.h.  The
175*0Sstevel@tonic-gate  * significant differences are:
176*0Sstevel@tonic-gate  *
177*0Sstevel@tonic-gate  * 1. This code recognizes only C99 (hex fp strings and restricted
178*0Sstevel@tonic-gate  *    characters in parentheses following "nan") vs. C90 modes, no
179*0Sstevel@tonic-gate  *    Fortran conventions.
180*0Sstevel@tonic-gate  *
181*0Sstevel@tonic-gate  * 2. *pform is an int rather than an enum decimal_string_form.  On
182*0Sstevel@tonic-gate  *    return, *pform == 0 if no valid token was found, *pform < 0
183*0Sstevel@tonic-gate  *    if a C99 hex fp string was found, and *pform > 0 if a decimal
184*0Sstevel@tonic-gate  *    string was found.
185*0Sstevel@tonic-gate  */
186*0Sstevel@tonic-gate static void
187*0Sstevel@tonic-gate wstring_to_decimal(const wchar_t **ppc, int c99, decimal_record *pd,
188*0Sstevel@tonic-gate     int *pform)
189*0Sstevel@tonic-gate {
190*0Sstevel@tonic-gate 	const wchar_t	*cp = *ppc; /* last character seen */
191*0Sstevel@tonic-gate 	const wchar_t	*good = cp - 1;	/* last character accepted */
192*0Sstevel@tonic-gate 	wchar_t		current; /* always equal to *cp */
193*0Sstevel@tonic-gate 	int		sigfound;
194*0Sstevel@tonic-gate 	int		ids = 0;
195*0Sstevel@tonic-gate 	int		i, agree;
196*0Sstevel@tonic-gate 	int		nzbp = 0; /* number of zeros before point */
197*0Sstevel@tonic-gate 	int		nzap = 0; /* number of zeros after point */
198*0Sstevel@tonic-gate 	char		decpt;
199*0Sstevel@tonic-gate 	int		nfast, nfastlimit;
200*0Sstevel@tonic-gate 	char		*pfast;
201*0Sstevel@tonic-gate 	int		e, esign;
202*0Sstevel@tonic-gate 	int		expshift = 0;
203*0Sstevel@tonic-gate 	int		form;
204*0Sstevel@tonic-gate 
205*0Sstevel@tonic-gate 	/*
206*0Sstevel@tonic-gate 	 * This routine assumes that the radix point is a single
207*0Sstevel@tonic-gate 	 * ASCII character, so that following this assignment, the
208*0Sstevel@tonic-gate 	 * condition (current == decpt) will correctly detect it.
209*0Sstevel@tonic-gate 	 */
210*0Sstevel@tonic-gate 	decpt = *(localeconv()->decimal_point);
211*0Sstevel@tonic-gate 
212*0Sstevel@tonic-gate 	/* input is invalid until we find something */
213*0Sstevel@tonic-gate 	pd->fpclass = fp_signaling;
214*0Sstevel@tonic-gate 	pd->sign = 0;
215*0Sstevel@tonic-gate 	pd->exponent = 0;
216*0Sstevel@tonic-gate 	pd->ds[0] = '\0';
217*0Sstevel@tonic-gate 	pd->more = 0;
218*0Sstevel@tonic-gate 	pd->ndigits = 0;
219*0Sstevel@tonic-gate 	*pform = form = 0;
220*0Sstevel@tonic-gate 
221*0Sstevel@tonic-gate 	/* skip white space */
222*0Sstevel@tonic-gate 	current = *cp;
223*0Sstevel@tonic-gate 	while (iswspace((wint_t)current))
224*0Sstevel@tonic-gate 		current = *++cp;
225*0Sstevel@tonic-gate 
226*0Sstevel@tonic-gate 	/* look for optional leading sign */
227*0Sstevel@tonic-gate 	if (current == L'+') {
228*0Sstevel@tonic-gate 		current = *++cp;
229*0Sstevel@tonic-gate 	} else if (current == L'-') {
230*0Sstevel@tonic-gate 		pd->sign = 1;
231*0Sstevel@tonic-gate 		current = *++cp;
232*0Sstevel@tonic-gate 	}
233*0Sstevel@tonic-gate 
234*0Sstevel@tonic-gate 	sigfound = -1;		/* -1 = no digits found yet */
235*0Sstevel@tonic-gate 
236*0Sstevel@tonic-gate 	/*
237*0Sstevel@tonic-gate 	 * Admissible first non-white-space, non-sign characters are
238*0Sstevel@tonic-gate 	 * 0-9, i, I, n, N, or the radix point.
239*0Sstevel@tonic-gate 	 */
240*0Sstevel@tonic-gate 	if (L'1' <= current && current <= L'9') {
241*0Sstevel@tonic-gate 		pd->fpclass = fp_normal;
242*0Sstevel@tonic-gate 		form = 1;
243*0Sstevel@tonic-gate 		good = cp;
244*0Sstevel@tonic-gate 		sigfound = 1;	/* 1 = significant digits found */
245*0Sstevel@tonic-gate 		pd->ds[ids++] = (char)current;
246*0Sstevel@tonic-gate 		current = *++cp;
247*0Sstevel@tonic-gate 	} else {
248*0Sstevel@tonic-gate 		switch (current) {
249*0Sstevel@tonic-gate 		case L'0':
250*0Sstevel@tonic-gate 			/*
251*0Sstevel@tonic-gate 			 * Accept the leading zero and set pd->fpclass
252*0Sstevel@tonic-gate 			 * accordingly, but don't set sigfound until we
253*0Sstevel@tonic-gate 			 * determine that this isn't a "fake" hex string
254*0Sstevel@tonic-gate 			 * (i.e., 0x.p...).
255*0Sstevel@tonic-gate 			 */
256*0Sstevel@tonic-gate 			good = cp;
257*0Sstevel@tonic-gate 			pd->fpclass = fp_zero;
258*0Sstevel@tonic-gate 			if (c99) {
259*0Sstevel@tonic-gate 				/* look for a hex fp string */
260*0Sstevel@tonic-gate 				current = *++cp;
261*0Sstevel@tonic-gate 				if (current == L'X' || current == L'x') {
262*0Sstevel@tonic-gate 					/* assume hex fp form */
263*0Sstevel@tonic-gate 					form = -1;
264*0Sstevel@tonic-gate 					expshift = 2;
265*0Sstevel@tonic-gate 					current = *++cp;
266*0Sstevel@tonic-gate 					/*
267*0Sstevel@tonic-gate 					 * Only a digit or radix point can
268*0Sstevel@tonic-gate 					 * follow "0x".
269*0Sstevel@tonic-gate 					 */
270*0Sstevel@tonic-gate 					if (NZDIGIT(current)) {
271*0Sstevel@tonic-gate 						pd->fpclass = fp_normal;
272*0Sstevel@tonic-gate 						good = cp;
273*0Sstevel@tonic-gate 						sigfound = 1;
274*0Sstevel@tonic-gate 						pd->ds[ids++] = (char)current;
275*0Sstevel@tonic-gate 						current = *++cp;
276*0Sstevel@tonic-gate 						break;
277*0Sstevel@tonic-gate 					} else if (current == (wchar_t)decpt) {
278*0Sstevel@tonic-gate 						current = *++cp;
279*0Sstevel@tonic-gate 						goto afterpoint;
280*0Sstevel@tonic-gate 					} else if (current != L'0') {
281*0Sstevel@tonic-gate 						/* not hex fp after all */
282*0Sstevel@tonic-gate 						form = 1;
283*0Sstevel@tonic-gate 						expshift = 0;
284*0Sstevel@tonic-gate 						goto done;
285*0Sstevel@tonic-gate 					}
286*0Sstevel@tonic-gate 				} else {
287*0Sstevel@tonic-gate 					form = 1;
288*0Sstevel@tonic-gate 				}
289*0Sstevel@tonic-gate 			} else {
290*0Sstevel@tonic-gate 				form = 1;
291*0Sstevel@tonic-gate 			}
292*0Sstevel@tonic-gate 
293*0Sstevel@tonic-gate 			/* skip all leading zeros */
294*0Sstevel@tonic-gate 			while (current == L'0')
295*0Sstevel@tonic-gate 				current = *++cp;
296*0Sstevel@tonic-gate 			good = cp - 1;
297*0Sstevel@tonic-gate 			sigfound = 0;	/* 0 = only zeros found so far */
298*0Sstevel@tonic-gate 			break;
299*0Sstevel@tonic-gate 
300*0Sstevel@tonic-gate 		case L'i':
301*0Sstevel@tonic-gate 		case L'I':
302*0Sstevel@tonic-gate 			/* look for inf or infinity */
303*0Sstevel@tonic-gate 			current = *++cp;
304*0Sstevel@tonic-gate 			agree = 1;
305*0Sstevel@tonic-gate 			while (agree <= 7 &&
306*0Sstevel@tonic-gate 			    UCASE(current) == (wchar_t)infstring[agree]) {
307*0Sstevel@tonic-gate 				current = *++cp;
308*0Sstevel@tonic-gate 				agree++;
309*0Sstevel@tonic-gate 			}
310*0Sstevel@tonic-gate 			if (agree >= 3) {
311*0Sstevel@tonic-gate 				/* found valid infinity */
312*0Sstevel@tonic-gate 				pd->fpclass = fp_infinity;
313*0Sstevel@tonic-gate 				form = 1;
314*0Sstevel@tonic-gate 				good = (agree < 8)? cp + 2 - agree : cp - 1;
315*0Sstevel@tonic-gate 				__inf_read = 1;
316*0Sstevel@tonic-gate 			}
317*0Sstevel@tonic-gate 			goto done;
318*0Sstevel@tonic-gate 
319*0Sstevel@tonic-gate 		case L'n':
320*0Sstevel@tonic-gate 		case L'N':
321*0Sstevel@tonic-gate 			/* look for nan or nan(string) */
322*0Sstevel@tonic-gate 			current = *++cp;
323*0Sstevel@tonic-gate 			agree = 1;
324*0Sstevel@tonic-gate 			while (agree <= 2 &&
325*0Sstevel@tonic-gate 			    UCASE(current) == (wchar_t)nanstring[agree]) {
326*0Sstevel@tonic-gate 				current = *++cp;
327*0Sstevel@tonic-gate 				agree++;
328*0Sstevel@tonic-gate 			}
329*0Sstevel@tonic-gate 			if (agree == 3) {
330*0Sstevel@tonic-gate 				/* found valid NaN */
331*0Sstevel@tonic-gate 				pd->fpclass = fp_quiet;
332*0Sstevel@tonic-gate 				form = 1;
333*0Sstevel@tonic-gate 				good = cp - 1;
334*0Sstevel@tonic-gate 				__nan_read = 1;
335*0Sstevel@tonic-gate 				if (current == L'(') {
336*0Sstevel@tonic-gate 					/* accept parenthesized string */
337*0Sstevel@tonic-gate 					if (c99) {
338*0Sstevel@tonic-gate 						do {
339*0Sstevel@tonic-gate 							current = *++cp;
340*0Sstevel@tonic-gate 						} while (iswalnum(current) ||
341*0Sstevel@tonic-gate 						    current == L'_');
342*0Sstevel@tonic-gate 					} else {
343*0Sstevel@tonic-gate 						do {
344*0Sstevel@tonic-gate 							current = *++cp;
345*0Sstevel@tonic-gate 						} while (current &&
346*0Sstevel@tonic-gate 						    current != L')');
347*0Sstevel@tonic-gate 					}
348*0Sstevel@tonic-gate 					if (current == L')')
349*0Sstevel@tonic-gate 						good = cp;
350*0Sstevel@tonic-gate 				}
351*0Sstevel@tonic-gate 			}
352*0Sstevel@tonic-gate 			goto done;
353*0Sstevel@tonic-gate 
354*0Sstevel@tonic-gate 		default:
355*0Sstevel@tonic-gate 			if (current == (wchar_t)decpt) {
356*0Sstevel@tonic-gate 				/*
357*0Sstevel@tonic-gate 				 * Don't accept the radix point just yet;
358*0Sstevel@tonic-gate 				 * we need to see at least one digit.
359*0Sstevel@tonic-gate 				 */
360*0Sstevel@tonic-gate 				current = *++cp;
361*0Sstevel@tonic-gate 				goto afterpoint;
362*0Sstevel@tonic-gate 			}
363*0Sstevel@tonic-gate 			goto done;
364*0Sstevel@tonic-gate 		}
365*0Sstevel@tonic-gate 	}
366*0Sstevel@tonic-gate 
367*0Sstevel@tonic-gate nextnumber:
368*0Sstevel@tonic-gate 	/*
369*0Sstevel@tonic-gate 	 * Admissible characters after the first digit are a valid
370*0Sstevel@tonic-gate 	 * digit, an exponent delimiter (E or e for decimal form,
371*0Sstevel@tonic-gate 	 * P or p for hex form), or the radix point.  (Note that we
372*0Sstevel@tonic-gate 	 * can't get here unless we've already found a digit.)
373*0Sstevel@tonic-gate 	 */
374*0Sstevel@tonic-gate 	if (NZDIGIT(current)) {
375*0Sstevel@tonic-gate 		/*
376*0Sstevel@tonic-gate 		 * Found another nonzero digit.  If there's enough room
377*0Sstevel@tonic-gate 		 * in pd->ds, store any intervening zeros we've found so far
378*0Sstevel@tonic-gate 		 * and then store this digit.  Otherwise, stop storing
379*0Sstevel@tonic-gate 		 * digits in pd->ds and set pd->more.
380*0Sstevel@tonic-gate 		 */
381*0Sstevel@tonic-gate 		if (ids + nzbp + 2 < DECIMAL_STRING_LENGTH) {
382*0Sstevel@tonic-gate 			for (i = 0; i < nzbp; i++)
383*0Sstevel@tonic-gate 				pd->ds[ids++] = '0';
384*0Sstevel@tonic-gate 			pd->ds[ids++] = (char)current;
385*0Sstevel@tonic-gate 		} else {
386*0Sstevel@tonic-gate 			pd->exponent += (nzbp + 1) << expshift;
387*0Sstevel@tonic-gate 			pd->more = 1;
388*0Sstevel@tonic-gate 			if (ids < DECIMAL_STRING_LENGTH) {
389*0Sstevel@tonic-gate 				pd->ds[ids] = '\0';
390*0Sstevel@tonic-gate 				pd->ndigits = ids;
391*0Sstevel@tonic-gate 				/* don't store any more digits */
392*0Sstevel@tonic-gate 				ids = DECIMAL_STRING_LENGTH;
393*0Sstevel@tonic-gate 			}
394*0Sstevel@tonic-gate 		}
395*0Sstevel@tonic-gate 		pd->fpclass = fp_normal;
396*0Sstevel@tonic-gate 		sigfound = 1;
397*0Sstevel@tonic-gate 		nzbp = 0;
398*0Sstevel@tonic-gate 		current = *++cp;
399*0Sstevel@tonic-gate 
400*0Sstevel@tonic-gate 		/*
401*0Sstevel@tonic-gate 		 * Use an optimized loop to grab a consecutive sequence
402*0Sstevel@tonic-gate 		 * of nonzero digits quickly.
403*0Sstevel@tonic-gate 		 */
404*0Sstevel@tonic-gate 		nfastlimit = DECIMAL_STRING_LENGTH - 3 - ids;
405*0Sstevel@tonic-gate 		for (nfast = 0, pfast = &(pd->ds[ids]);
406*0Sstevel@tonic-gate 		    nfast < nfastlimit && NZDIGIT(current);
407*0Sstevel@tonic-gate 		    nfast++) {
408*0Sstevel@tonic-gate 			*pfast++ = (char)current;
409*0Sstevel@tonic-gate 			current = *++cp;
410*0Sstevel@tonic-gate 		}
411*0Sstevel@tonic-gate 		ids += nfast;
412*0Sstevel@tonic-gate 		if (current == L'0')
413*0Sstevel@tonic-gate 			goto nextnumberzero;	/* common case */
414*0Sstevel@tonic-gate 		/* advance good to the last accepted digit */
415*0Sstevel@tonic-gate 		good = cp - 1;
416*0Sstevel@tonic-gate 		goto nextnumber;
417*0Sstevel@tonic-gate 	} else {
418*0Sstevel@tonic-gate 		switch (current) {
419*0Sstevel@tonic-gate 		case L'0':
420*0Sstevel@tonic-gate nextnumberzero:
421*0Sstevel@tonic-gate 			/*
422*0Sstevel@tonic-gate 			 * Count zeros before the radix point.  Later we
423*0Sstevel@tonic-gate 			 * will either put these zeros into pd->ds or add
424*0Sstevel@tonic-gate 			 * nzbp to pd->exponent to account for them.
425*0Sstevel@tonic-gate 			 */
426*0Sstevel@tonic-gate 			while (current == L'0') {
427*0Sstevel@tonic-gate 				nzbp++;
428*0Sstevel@tonic-gate 				current = *++cp;
429*0Sstevel@tonic-gate 			}
430*0Sstevel@tonic-gate 			good = cp - 1;
431*0Sstevel@tonic-gate 			goto nextnumber;
432*0Sstevel@tonic-gate 
433*0Sstevel@tonic-gate 		case L'E':
434*0Sstevel@tonic-gate 		case L'e':
435*0Sstevel@tonic-gate 			if (form < 0)
436*0Sstevel@tonic-gate 				goto done;
437*0Sstevel@tonic-gate 			goto exponent;
438*0Sstevel@tonic-gate 
439*0Sstevel@tonic-gate 		case L'P':
440*0Sstevel@tonic-gate 		case L'p':
441*0Sstevel@tonic-gate 			if (form > 0)
442*0Sstevel@tonic-gate 				goto done;
443*0Sstevel@tonic-gate 			goto exponent;
444*0Sstevel@tonic-gate 
445*0Sstevel@tonic-gate 		default:
446*0Sstevel@tonic-gate 			if (current == decpt) {
447*0Sstevel@tonic-gate 				/* accept the radix point */
448*0Sstevel@tonic-gate 				good = cp;
449*0Sstevel@tonic-gate 				current = *++cp;
450*0Sstevel@tonic-gate 				goto afterpoint;
451*0Sstevel@tonic-gate 			}
452*0Sstevel@tonic-gate 			goto done;
453*0Sstevel@tonic-gate 		}
454*0Sstevel@tonic-gate 	}
455*0Sstevel@tonic-gate 
456*0Sstevel@tonic-gate afterpoint:
457*0Sstevel@tonic-gate 	/*
458*0Sstevel@tonic-gate 	 * Admissible characters after the radix point are a valid digit
459*0Sstevel@tonic-gate 	 * or an exponent delimiter.  (Note that it is possible to get
460*0Sstevel@tonic-gate 	 * here even though we haven't found any digits yet.)
461*0Sstevel@tonic-gate 	 */
462*0Sstevel@tonic-gate 	if (NZDIGIT(current)) {
463*0Sstevel@tonic-gate 		if (form == 0)
464*0Sstevel@tonic-gate 			form = 1;
465*0Sstevel@tonic-gate 		if (sigfound < 1) {
466*0Sstevel@tonic-gate 			/* no significant digits found until now */
467*0Sstevel@tonic-gate 			pd->fpclass = fp_normal;
468*0Sstevel@tonic-gate 			sigfound = 1;
469*0Sstevel@tonic-gate 			pd->ds[ids++] = (char)current;
470*0Sstevel@tonic-gate 			pd->exponent = (-(nzap + 1)) << expshift;
471*0Sstevel@tonic-gate 		} else {
472*0Sstevel@tonic-gate 			/* significant digits have been found */
473*0Sstevel@tonic-gate 			if (ids + nzbp + nzap + 2 < DECIMAL_STRING_LENGTH) {
474*0Sstevel@tonic-gate 				for (i = 0; i < nzbp + nzap; i++)
475*0Sstevel@tonic-gate 					pd->ds[ids++] = '0';
476*0Sstevel@tonic-gate 				pd->ds[ids++] = (char)current;
477*0Sstevel@tonic-gate 				pd->exponent -= (nzap + 1) << expshift;
478*0Sstevel@tonic-gate 			} else {
479*0Sstevel@tonic-gate 				pd->exponent += nzbp << expshift;
480*0Sstevel@tonic-gate 				pd->more = 1;
481*0Sstevel@tonic-gate 				if (ids < DECIMAL_STRING_LENGTH) {
482*0Sstevel@tonic-gate 					pd->ds[ids] = '\0';
483*0Sstevel@tonic-gate 					pd->ndigits = ids;
484*0Sstevel@tonic-gate 					/* don't store any more digits */
485*0Sstevel@tonic-gate 					ids = DECIMAL_STRING_LENGTH;
486*0Sstevel@tonic-gate 				}
487*0Sstevel@tonic-gate 			}
488*0Sstevel@tonic-gate 		}
489*0Sstevel@tonic-gate 		nzbp = 0;
490*0Sstevel@tonic-gate 		nzap = 0;
491*0Sstevel@tonic-gate 		current = *++cp;
492*0Sstevel@tonic-gate 
493*0Sstevel@tonic-gate 		/*
494*0Sstevel@tonic-gate 		 * Use an optimized loop to grab a consecutive sequence
495*0Sstevel@tonic-gate 		 * of nonzero digits quickly.
496*0Sstevel@tonic-gate 		 */
497*0Sstevel@tonic-gate 		nfastlimit = DECIMAL_STRING_LENGTH - 3 - ids;
498*0Sstevel@tonic-gate 		for (nfast = 0, pfast = &(pd->ds[ids]);
499*0Sstevel@tonic-gate 		    nfast < nfastlimit && NZDIGIT(current);
500*0Sstevel@tonic-gate 		    nfast++) {
501*0Sstevel@tonic-gate 			*pfast++ = (char)current;
502*0Sstevel@tonic-gate 			current = *++cp;
503*0Sstevel@tonic-gate 		}
504*0Sstevel@tonic-gate 		ids += nfast;
505*0Sstevel@tonic-gate 		pd->exponent -= nfast << expshift;
506*0Sstevel@tonic-gate 		if (current == L'0')
507*0Sstevel@tonic-gate 			goto zeroafterpoint;
508*0Sstevel@tonic-gate 		/* advance good to the last accepted digit */
509*0Sstevel@tonic-gate 		good = cp - 1;
510*0Sstevel@tonic-gate 		goto afterpoint;
511*0Sstevel@tonic-gate 	} else {
512*0Sstevel@tonic-gate 		switch (current) {
513*0Sstevel@tonic-gate 		case L'0':
514*0Sstevel@tonic-gate 			if (form == 0)
515*0Sstevel@tonic-gate 				form = 1;
516*0Sstevel@tonic-gate 			if (sigfound == -1) {
517*0Sstevel@tonic-gate 				pd->fpclass = fp_zero;
518*0Sstevel@tonic-gate 				sigfound = 0;
519*0Sstevel@tonic-gate 			}
520*0Sstevel@tonic-gate zeroafterpoint:
521*0Sstevel@tonic-gate 			/*
522*0Sstevel@tonic-gate 			 * Count zeros after the radix point.  If we find
523*0Sstevel@tonic-gate 			 * any more nonzero digits later, we will put these
524*0Sstevel@tonic-gate 			 * zeros into pd->ds and decrease pd->exponent by
525*0Sstevel@tonic-gate 			 * nzap.
526*0Sstevel@tonic-gate 			 */
527*0Sstevel@tonic-gate 			while (current == L'0') {
528*0Sstevel@tonic-gate 				nzap++;
529*0Sstevel@tonic-gate 				current = *++cp;
530*0Sstevel@tonic-gate 			}
531*0Sstevel@tonic-gate 			good = cp - 1;
532*0Sstevel@tonic-gate 			goto afterpoint;
533*0Sstevel@tonic-gate 
534*0Sstevel@tonic-gate 		case L'E':
535*0Sstevel@tonic-gate 		case L'e':
536*0Sstevel@tonic-gate 			/* don't accept exponent without preceding digits */
537*0Sstevel@tonic-gate 			if (sigfound == -1 || form < 0)
538*0Sstevel@tonic-gate 				goto done;
539*0Sstevel@tonic-gate 			break;
540*0Sstevel@tonic-gate 
541*0Sstevel@tonic-gate 		case L'P':
542*0Sstevel@tonic-gate 		case L'p':
543*0Sstevel@tonic-gate 			/* don't accept exponent without preceding digits */
544*0Sstevel@tonic-gate 			if (sigfound == -1 || form > 0)
545*0Sstevel@tonic-gate 				goto done;
546*0Sstevel@tonic-gate 			break;
547*0Sstevel@tonic-gate 
548*0Sstevel@tonic-gate 		default:
549*0Sstevel@tonic-gate 			goto done;
550*0Sstevel@tonic-gate 		}
551*0Sstevel@tonic-gate 	}
552*0Sstevel@tonic-gate 
553*0Sstevel@tonic-gate exponent:
554*0Sstevel@tonic-gate 	e = 0;
555*0Sstevel@tonic-gate 	esign = 0;
556*0Sstevel@tonic-gate 
557*0Sstevel@tonic-gate 	/* look for optional exponent sign */
558*0Sstevel@tonic-gate 	current = *++cp;
559*0Sstevel@tonic-gate 	if (current == L'+') {
560*0Sstevel@tonic-gate 		current = *++cp;
561*0Sstevel@tonic-gate 	} else if (current == L'-') {
562*0Sstevel@tonic-gate 		esign = 1;
563*0Sstevel@tonic-gate 		current = *++cp;
564*0Sstevel@tonic-gate 	}
565*0Sstevel@tonic-gate 
566*0Sstevel@tonic-gate 	/*
567*0Sstevel@tonic-gate 	 * Accumulate explicit exponent.  Note that if we don't find at
568*0Sstevel@tonic-gate 	 * least one digit, good won't be updated and e will remain 0.
569*0Sstevel@tonic-gate 	 * Also, we keep e from getting too large so we don't overflow
570*0Sstevel@tonic-gate 	 * the range of int (but notice that the threshold is large
571*0Sstevel@tonic-gate 	 * enough that any larger e would cause the result to underflow
572*0Sstevel@tonic-gate 	 * or overflow anyway).
573*0Sstevel@tonic-gate 	 */
574*0Sstevel@tonic-gate 	while (L'0' <= current && current <= L'9') {
575*0Sstevel@tonic-gate 		good = cp;
576*0Sstevel@tonic-gate 		if (e <= 1000000)
577*0Sstevel@tonic-gate 			e = 10 * e + current - L'0';
578*0Sstevel@tonic-gate 		current = *++cp;
579*0Sstevel@tonic-gate 	}
580*0Sstevel@tonic-gate 	if (esign)
581*0Sstevel@tonic-gate 		pd->exponent -= e;
582*0Sstevel@tonic-gate 	else
583*0Sstevel@tonic-gate 		pd->exponent += e;
584*0Sstevel@tonic-gate 
585*0Sstevel@tonic-gate done:
586*0Sstevel@tonic-gate 	/*
587*0Sstevel@tonic-gate 	 * If we found any zeros before the radix point that were not
588*0Sstevel@tonic-gate 	 * accounted for earlier, adjust the exponent.  (This is only
589*0Sstevel@tonic-gate 	 * relevant when pd->fpclass == fp_normal, but it's harmless
590*0Sstevel@tonic-gate 	 * in all other cases.)
591*0Sstevel@tonic-gate 	 */
592*0Sstevel@tonic-gate 	pd->exponent += nzbp << expshift;
593*0Sstevel@tonic-gate 
594*0Sstevel@tonic-gate 	/* terminate pd->ds if we haven't already */
595*0Sstevel@tonic-gate 	if (ids < DECIMAL_STRING_LENGTH) {
596*0Sstevel@tonic-gate 		pd->ds[ids] = '\0';
597*0Sstevel@tonic-gate 		pd->ndigits = ids;
598*0Sstevel@tonic-gate 	}
599*0Sstevel@tonic-gate 
600*0Sstevel@tonic-gate 	/*
601*0Sstevel@tonic-gate 	 * If we accepted any characters, advance *ppc to point to the
602*0Sstevel@tonic-gate 	 * first character we didn't accept; otherwise, pass back a
603*0Sstevel@tonic-gate 	 * signaling nan.
604*0Sstevel@tonic-gate 	 */
605*0Sstevel@tonic-gate 	if (good >= *ppc) {
606*0Sstevel@tonic-gate 		*ppc = good + 1;
607*0Sstevel@tonic-gate 	} else {
608*0Sstevel@tonic-gate 		pd->fpclass = fp_signaling;
609*0Sstevel@tonic-gate 		pd->sign = 0;
610*0Sstevel@tonic-gate 		form = 0;
611*0Sstevel@tonic-gate 	}
612*0Sstevel@tonic-gate 
613*0Sstevel@tonic-gate 	*pform = form;
614*0Sstevel@tonic-gate }
615