1 /*-
2 * Copyright (c) 1990, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Chris Torek.
7 *
8 * Copyright (c) 2011 The FreeBSD Foundation
9 * All rights reserved.
10 * Portions of this software were developed by David Chisnall
11 * under sponsorship from the FreeBSD Foundation.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 * $FreeBSD: head/lib/libc/stdio/printfcommon.h 227753 2011-11-20 14:45:42Z theraven $
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
58 static int exponent(CHAR *, int, CHAR);
59
60 #endif /* !NO_FLOATING_POINT */
61
62 static CHAR *__ujtoa(uintmax_t, CHAR *, int, int, const char *);
63 static CHAR *__ultoa(u_long, CHAR *, int, int, const char *);
64
65 #define NIOV 8
66 struct io_state {
67 FILE *fp;
68 struct __suio uio; /* output information: summary */
69 struct __siov iov[NIOV];/* ... and individual io vectors */
70 };
71
72 static inline void
io_init(struct io_state * iop,FILE * fp)73 io_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 */
86 static inline int
io_print(struct io_state * iop,const CHAR * __restrict ptr,int len,locale_t locale)87 io_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 */
105 static const CHAR blanks[PADSIZE] =
106 {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '};
107 static 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 */
114 static inline int
io_pad(struct io_state * iop,int howmany,const CHAR * __restrict with,locale_t locale)115 io_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 */
133 static inline int
io_printandpad(struct io_state * iop,const CHAR * p,const CHAR * ep,int len,const CHAR * __restrict with,locale_t locale)134 io_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
151 static inline int
io_flush(struct io_state * iop,locale_t locale)152 io_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 */
164 static CHAR *
__ultoa(u_long val,CHAR * endp,int base,int octzero,const char * xdigs)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 8:
198 do {
199 *--cp = to_char(val & 7);
200 val >>= 3;
201 } while (val);
202 if (octzero && *cp != '0')
203 *--cp = '0';
204 break;
205
206 case 16:
207 do {
208 *--cp = xdigs[val & 15];
209 val >>= 4;
210 } while (val);
211 break;
212
213 default: /* oops */
214 abort();
215 }
216 return (cp);
217 }
218
219 /* Identical to __ultoa, but for intmax_t. */
220 static CHAR *
__ujtoa(uintmax_t val,CHAR * endp,int base,int octzero,const char * xdigs)221 __ujtoa(uintmax_t val, CHAR *endp, int base, int octzero, const char *xdigs)
222 {
223 CHAR *cp = endp;
224 intmax_t sval;
225
226 /* quick test for small values; __ultoa is typically much faster */
227 /* (perhaps instead we should run until small, then call __ultoa?) */
228 if (val <= ULONG_MAX)
229 return (__ultoa((u_long)val, endp, base, octzero, xdigs));
230 switch (base) {
231 case 10:
232 if (val > INTMAX_MAX) {
233 *--cp = to_char(val % 10);
234 sval = val / 10;
235 } else
236 sval = val;
237 do {
238 *--cp = to_char(sval % 10);
239 sval /= 10;
240 } while (sval != 0);
241 break;
242
243 case 8:
244 do {
245 *--cp = to_char(val & 7);
246 val >>= 3;
247 } while (val);
248 if (octzero && *cp != '0')
249 *--cp = '0';
250 break;
251
252 case 16:
253 do {
254 *--cp = xdigs[val & 15];
255 val >>= 4;
256 } while (val);
257 break;
258
259 default:
260 abort();
261 }
262 return (cp);
263 }
264
265 #ifndef NO_FLOATING_POINT
266
267 static int
exponent(CHAR * p0,int exp,CHAR fmtch)268 exponent(CHAR *p0, int exp, CHAR fmtch)
269 {
270 CHAR *p, *t;
271 CHAR expbuf[MAXEXPDIG];
272
273 p = p0;
274 *p++ = fmtch;
275 if (exp < 0) {
276 exp = -exp;
277 *p++ = '-';
278 }
279 else
280 *p++ = '+';
281 t = expbuf + MAXEXPDIG;
282 if (exp > 9) {
283 do {
284 *--t = to_char(exp % 10);
285 } while ((exp /= 10) > 9);
286 *--t = to_char(exp);
287 for (; t < expbuf + MAXEXPDIG; *p++ = *t++);
288 }
289 else {
290 /*
291 * Exponents for decimal floating point conversions
292 * (%[eEgG]) must be at least two characters long,
293 * whereas exponents for hexadecimal conversions can
294 * be only one character long.
295 */
296 if (fmtch == 'e' || fmtch == 'E')
297 *p++ = '0';
298 *p++ = to_char(exp);
299 }
300 return (p - p0);
301 }
302
303 #endif /* !NO_FLOATING_POINT */
304