1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1990, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Chris Torek.
9 *
10 * Copyright (c) 2011 The FreeBSD Foundation
11 *
12 * Portions of this software were developed by David Chisnall
13 * under sponsorship from the FreeBSD Foundation.
14 *
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
17 * are met:
18 * 1. Redistributions of source code must retain the above copyright
19 *    notice, this list of conditions and the following disclaimer.
20 * 2. Redistributions in binary form must reproduce the above copyright
21 *    notice, this list of conditions and the following disclaimer in the
22 *    documentation and/or other materials provided with the distribution.
23 * 3. Neither the name of the University nor the names of its contributors
24 *    may be used to endorse or promote products derived from this software
25 *    without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 */
39
40/*
41 * This file defines common routines used by both printf and wprintf.
42 * You must define CHAR to either char or wchar_t prior to including this.
43 */
44
45
46#ifndef NO_FLOATING_POINT
47
48#define	dtoa		__dtoa
49#define	freedtoa	__freedtoa
50
51#include <float.h>
52#include <math.h>
53#include "floatio.h"
54#include "gdtoa.h"
55
56#define	DEFPREC		6
57
58static int exponent(CHAR *, int, CHAR);
59
60#endif /* !NO_FLOATING_POINT */
61
62static CHAR	*__ujtoa(uintmax_t, CHAR *, int, int, const char *);
63static CHAR	*__ultoa(u_long, CHAR *, int, int, const char *);
64
65#define NIOV 8
66struct io_state {
67	FILE *fp;
68	struct __suio uio;	/* output information: summary */
69	struct __siov iov[NIOV];/* ... and individual io vectors */
70};
71
72static inline void
73io_init(struct io_state *iop, FILE *fp)
74{
75
76	iop->uio.uio_iov = iop->iov;
77	iop->uio.uio_resid = 0;
78	iop->uio.uio_iovcnt = 0;
79	iop->fp = fp;
80}
81
82/*
83 * WARNING: The buffer passed to io_print() is not copied immediately; it must
84 * remain valid until io_flush() is called.
85 */
86static inline int
87io_print(struct io_state *iop, const CHAR * __restrict ptr, int len, locale_t locale)
88{
89
90	iop->iov[iop->uio.uio_iovcnt].iov_base = (char *)ptr;
91	iop->iov[iop->uio.uio_iovcnt].iov_len = len;
92	iop->uio.uio_resid += len;
93	if (++iop->uio.uio_iovcnt >= NIOV)
94		return (__sprint(iop->fp, &iop->uio, locale));
95	else
96		return (0);
97}
98
99/*
100 * Choose PADSIZE to trade efficiency vs. size.  If larger printf
101 * fields occur frequently, increase PADSIZE and make the initialisers
102 * below longer.
103 */
104#define	PADSIZE	16		/* pad chunk size */
105static const CHAR blanks[PADSIZE] =
106{' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '};
107static const CHAR zeroes[PADSIZE] =
108{'0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0'};
109
110/*
111 * Pad with blanks or zeroes. 'with' should point to either the blanks array
112 * or the zeroes array.
113 */
114static inline int
115io_pad(struct io_state *iop, int howmany, const CHAR * __restrict with,
116		locale_t locale)
117{
118	int n;
119
120	while (howmany > 0) {
121		n = (howmany >= PADSIZE) ? PADSIZE : howmany;
122		if (io_print(iop, with, n, locale))
123			return (-1);
124		howmany -= n;
125	}
126	return (0);
127}
128
129/*
130 * Print exactly len characters of the string spanning p to ep, truncating
131 * or padding with 'with' as necessary.
132 */
133static inline int
134io_printandpad(struct io_state *iop, const CHAR *p, const CHAR *ep,
135	       int len, const CHAR * __restrict with, locale_t locale)
136{
137	int p_len;
138
139	p_len = ep - p;
140	if (p_len > len)
141		p_len = len;
142	if (p_len > 0) {
143		if (io_print(iop, p, p_len, locale))
144			return (-1);
145	} else {
146		p_len = 0;
147	}
148	return (io_pad(iop, len - p_len, with, locale));
149}
150
151static inline int
152io_flush(struct io_state *iop, locale_t locale)
153{
154
155	return (__sprint(iop->fp, &iop->uio, locale));
156}
157
158/*
159 * Convert an unsigned long to ASCII for printf purposes, returning
160 * a pointer to the first character of the string representation.
161 * Octal numbers can be forced to have a leading zero; hex numbers
162 * use the given digits.
163 */
164static CHAR *
165__ultoa(u_long val, CHAR *endp, int base, int octzero, const char *xdigs)
166{
167	CHAR *cp = endp;
168	long sval;
169
170	/*
171	 * Handle the three cases separately, in the hope of getting
172	 * better/faster code.
173	 */
174	switch (base) {
175	case 10:
176		if (val < 10) {	/* many numbers are 1 digit */
177			*--cp = to_char(val);
178			return (cp);
179		}
180		/*
181		 * On many machines, unsigned arithmetic is harder than
182		 * signed arithmetic, so we do at most one unsigned mod and
183		 * divide; this is sufficient to reduce the range of
184		 * the incoming value to where signed arithmetic works.
185		 */
186		if (val > LONG_MAX) {
187			*--cp = to_char(val % 10);
188			sval = val / 10;
189		} else
190			sval = val;
191		do {
192			*--cp = to_char(sval % 10);
193			sval /= 10;
194		} while (sval != 0);
195		break;
196
197	case 2:
198		do {
199			*--cp = to_char(val & 1);
200			val >>= 1;
201		} while (val);
202		break;
203
204	case 8:
205		do {
206			*--cp = to_char(val & 7);
207			val >>= 3;
208		} while (val);
209		if (octzero && *cp != '0')
210			*--cp = '0';
211		break;
212
213	case 16:
214		do {
215			*--cp = xdigs[val & 15];
216			val >>= 4;
217		} while (val);
218		break;
219
220	default:			/* oops */
221		abort();
222	}
223	return (cp);
224}
225
226/* Identical to __ultoa, but for intmax_t. */
227static CHAR *
228__ujtoa(uintmax_t val, CHAR *endp, int base, int octzero, const char *xdigs)
229{
230	CHAR *cp = endp;
231	intmax_t sval;
232
233	/* quick test for small values; __ultoa is typically much faster */
234	/* (perhaps instead we should run until small, then call __ultoa?) */
235	if (val <= ULONG_MAX)
236		return (__ultoa((u_long)val, endp, base, octzero, xdigs));
237	switch (base) {
238	case 10:
239		if (val < 10) {
240			*--cp = to_char(val % 10);
241			return (cp);
242		}
243		if (val > INTMAX_MAX) {
244			*--cp = to_char(val % 10);
245			sval = val / 10;
246		} else
247			sval = val;
248		do {
249			*--cp = to_char(sval % 10);
250			sval /= 10;
251		} while (sval != 0);
252		break;
253
254	case 2:
255		do {
256			*--cp = to_char(val & 1);
257			val >>= 1;
258		} while (val);
259		break;
260
261	case 8:
262		do {
263			*--cp = to_char(val & 7);
264			val >>= 3;
265		} while (val);
266		if (octzero && *cp != '0')
267			*--cp = '0';
268		break;
269
270	case 16:
271		do {
272			*--cp = xdigs[val & 15];
273			val >>= 4;
274		} while (val);
275		break;
276
277	default:
278		abort();
279	}
280	return (cp);
281}
282
283#ifndef NO_FLOATING_POINT
284
285static int
286exponent(CHAR *p0, int exp, CHAR fmtch)
287{
288	CHAR *p, *t;
289	CHAR expbuf[MAXEXPDIG];
290
291	p = p0;
292	*p++ = fmtch;
293	if (exp < 0) {
294		exp = -exp;
295		*p++ = '-';
296	}
297	else
298		*p++ = '+';
299	t = expbuf + MAXEXPDIG;
300	if (exp > 9) {
301		do {
302			*--t = to_char(exp % 10);
303		} while ((exp /= 10) > 9);
304		*--t = to_char(exp);
305		for (; t < expbuf + MAXEXPDIG; *p++ = *t++);
306	}
307	else {
308		/*
309		 * Exponents for decimal floating point conversions
310		 * (%[eEgG]) must be at least two characters long,
311		 * whereas exponents for hexadecimal conversions can
312		 * be only one character long.
313		 */
314		if (fmtch == 'e' || fmtch == 'E')
315			*p++ = '0';
316		*p++ = to_char(exp);
317	}
318	return (p - p0);
319}
320
321#endif /* !NO_FLOATING_POINT */
322