xref: /freebsd/lib/libc/stdlib/strfmon.c (revision 076ad2f8)
1 /*-
2  * Copyright (c) 2001 Alexey Zelkin <phantom@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Copyright (c) 2011 The FreeBSD Foundation
6  * All rights reserved.
7  * Portions of this software were developed by David Chisnall
8  * under sponsorship from the FreeBSD Foundation.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/types.h>
37 #include <ctype.h>
38 #include <errno.h>
39 #include <limits.h>
40 #include <locale.h>
41 #include <monetary.h>
42 #include <stdarg.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include "xlocale_private.h"
47 
48 /* internal flags */
49 #define	NEED_GROUPING		0x01	/* print digits grouped (default) */
50 #define	SIGN_POSN_USED		0x02	/* '+' or '(' usage flag */
51 #define	LOCALE_POSN		0x04	/* use locale defined +/- (default) */
52 #define	PARENTH_POSN		0x08	/* enclose negative amount in () */
53 #define	SUPRESS_CURR_SYMBOL	0x10	/* suppress the currency from output */
54 #define	LEFT_JUSTIFY		0x20	/* left justify */
55 #define	USE_INTL_CURRENCY	0x40	/* use international currency symbol */
56 #define IS_NEGATIVE		0x80	/* is argument value negative ? */
57 
58 /* internal macros */
59 #define PRINT(CH) do {						\
60 	if (dst >= s + maxsize) 				\
61 		goto e2big_error;				\
62 	*dst++ = CH;						\
63 } while (0)
64 
65 #define PRINTS(STR) do {					\
66 	char *tmps = STR;					\
67 	while (*tmps != '\0')					\
68 		PRINT(*tmps++);					\
69 } while (0)
70 
71 #define GET_NUMBER(VAR)	do {					\
72 	VAR = 0;						\
73 	while (isdigit((unsigned char)*fmt)) {			\
74 		if (VAR > INT_MAX / 10)				\
75 			goto e2big_error;			\
76 		VAR *= 10;					\
77 		VAR += *fmt - '0';				\
78 		if (VAR < 0)					\
79 			goto e2big_error;			\
80 		fmt++;						\
81 	}							\
82 } while (0)
83 
84 #define GRPCPY(howmany) do {					\
85 	int i = howmany;					\
86 	while (i-- > 0) {					\
87 		avalue_size--;					\
88 		*--bufend = *(avalue+avalue_size+padded);	\
89 	}							\
90 } while (0)
91 
92 #define GRPSEP do {						\
93 	*--bufend = thousands_sep;				\
94 	groups++;						\
95 } while (0)
96 
97 static void __setup_vars(int, char *, char *, char *, char **);
98 static int __calc_left_pad(int, char *);
99 static char *__format_grouped_double(double, int *, int, int, int);
100 
101 static ssize_t
102 vstrfmon_l(char * __restrict s, size_t maxsize, locale_t loc,
103 		const char * __restrict format, va_list ap)
104 {
105 	char 		*dst;		/* output destination pointer */
106 	const char 	*fmt;		/* current format poistion pointer */
107 	struct lconv 	*lc;		/* pointer to lconv structure */
108 	char		*asciivalue;	/* formatted double pointer */
109 
110 	int		flags;		/* formatting options */
111 	int		pad_char;	/* padding character */
112 	int		pad_size;	/* pad size */
113 	int		width;		/* field width */
114 	int		left_prec;	/* left precision */
115 	int		right_prec;	/* right precision */
116 	double		value;		/* just value */
117 	char		space_char = ' '; /* space after currency */
118 
119 	char		cs_precedes,	/* values gathered from struct lconv */
120 			sep_by_space,
121 			sign_posn,
122 			*signstr,
123 			*currency_symbol;
124 
125 	char		*tmpptr;	/* temporary vars */
126 	int		sverrno;
127 	FIX_LOCALE(loc);
128 
129 
130 	lc = localeconv_l(loc);
131 	dst = s;
132 	fmt = format;
133 	asciivalue = NULL;
134 	currency_symbol = NULL;
135 	pad_size = 0;
136 
137 	while (*fmt) {
138 		/* pass nonformating characters AS IS */
139 		if (*fmt != '%')
140 			goto literal;
141 
142 		/* '%' found ! */
143 
144 		/* "%%" mean just '%' */
145 		if (*(fmt+1) == '%') {
146 			fmt++;
147 	literal:
148 			PRINT(*fmt++);
149 			continue;
150 		}
151 
152 		/* set up initial values */
153 		flags = (NEED_GROUPING|LOCALE_POSN);
154 		pad_char = ' ';		/* padding character is "space" */
155 		left_prec = -1;		/* no left precision specified */
156 		right_prec = -1;	/* no right precision specified */
157 		width = -1;		/* no width specified */
158 		value = 0;		/* we have no value to print now */
159 
160 		/* Flags */
161 		while (1) {
162 			switch (*++fmt) {
163 				case '=':	/* fill character */
164 					pad_char = *++fmt;
165 					if (pad_char == '\0')
166 						goto format_error;
167 					continue;
168 				case '^':	/* not group currency  */
169 					flags &= ~(NEED_GROUPING);
170 					continue;
171 				case '+':	/* use locale defined signs */
172 					if (flags & SIGN_POSN_USED)
173 						goto format_error;
174 					flags |= (SIGN_POSN_USED|LOCALE_POSN);
175 					continue;
176 				case '(':	/* enclose negatives with () */
177 					if (flags & SIGN_POSN_USED)
178 						goto format_error;
179 					flags |= (SIGN_POSN_USED|PARENTH_POSN);
180 					continue;
181 				case '!':	/* suppress currency symbol */
182 					flags |= SUPRESS_CURR_SYMBOL;
183 					continue;
184 				case '-':	/* alignment (left)  */
185 					flags |= LEFT_JUSTIFY;
186 					continue;
187 				default:
188 					break;
189 			}
190 			break;
191 		}
192 
193 		/* field Width */
194 		if (isdigit((unsigned char)*fmt)) {
195 			GET_NUMBER(width);
196 			/* Do we have enough space to put number with
197 			 * required width ?
198 			 */
199 			if ((unsigned int)width >= maxsize - (dst - s))
200 				goto e2big_error;
201 		}
202 
203 		/* Left precision */
204 		if (*fmt == '#') {
205 			if (!isdigit((unsigned char)*++fmt))
206 				goto format_error;
207 			GET_NUMBER(left_prec);
208 			if ((unsigned int)left_prec >= maxsize - (dst - s))
209 				goto e2big_error;
210 		}
211 
212 		/* Right precision */
213 		if (*fmt == '.') {
214 			if (!isdigit((unsigned char)*++fmt))
215 				goto format_error;
216 			GET_NUMBER(right_prec);
217 			if ((unsigned int)right_prec >= maxsize - (dst - s) -
218 			    left_prec)
219 				goto e2big_error;
220 		}
221 
222 		/* Conversion Characters */
223 		switch (*fmt++) {
224 			case 'i':	/* use internaltion currency format */
225 				flags |= USE_INTL_CURRENCY;
226 				break;
227 			case 'n':	/* use national currency format */
228 				flags &= ~(USE_INTL_CURRENCY);
229 				break;
230 			default:	/* required character is missing or
231 					   premature EOS */
232 				goto format_error;
233 		}
234 
235 		if (currency_symbol != NULL)
236 			free(currency_symbol);
237 		if (flags & USE_INTL_CURRENCY) {
238 			currency_symbol = strdup(lc->int_curr_symbol);
239 			if (currency_symbol != NULL)
240 				space_char = *(currency_symbol+3);
241 		} else
242 			currency_symbol = strdup(lc->currency_symbol);
243 
244 		if (currency_symbol == NULL)
245 			goto end_error;			/* ENOMEM. */
246 
247 		/* value itself */
248 		value = va_arg(ap, double);
249 
250 		/* detect sign */
251 		if (value < 0) {
252 			flags |= IS_NEGATIVE;
253 			value = -value;
254 		}
255 
256 		/* fill left_prec with amount of padding chars */
257 		if (left_prec >= 0) {
258 			pad_size = __calc_left_pad((flags ^ IS_NEGATIVE),
259 							currency_symbol) -
260 				   __calc_left_pad(flags, currency_symbol);
261 			if (pad_size < 0)
262 				pad_size = 0;
263 		}
264 
265 		if (asciivalue != NULL)
266 			free(asciivalue);
267 		asciivalue = __format_grouped_double(value, &flags,
268 				left_prec, right_prec, pad_char);
269 		if (asciivalue == NULL)
270 			goto end_error;		/* errno already set     */
271 						/* to ENOMEM by malloc() */
272 
273 		/* set some variables for later use */
274 		__setup_vars(flags, &cs_precedes, &sep_by_space,
275 				&sign_posn, &signstr);
276 
277 		/*
278 		 * Description of some LC_MONETARY's values:
279 		 *
280 		 * p_cs_precedes & n_cs_precedes
281 		 *
282 		 * = 1 - $currency_symbol precedes the value
283 		 *       for a monetary quantity with a non-negative value
284 		 * = 0 - symbol succeeds the value
285 		 *
286 		 * p_sep_by_space & n_sep_by_space
287                  *
288 		 * = 0 - no space separates $currency_symbol
289 		 *       from the value for a monetary quantity with a
290 		 *	 non-negative value
291 		 * = 1 - space separates the symbol from the value
292 		 * = 2 - space separates the symbol and the sign string,
293 		 *       if adjacent.
294                  *
295 		 * p_sign_posn & n_sign_posn
296                  *
297 		 * = 0 - parentheses enclose the quantity and the
298 		 *	 $currency_symbol
299 		 * = 1 - the sign string precedes the quantity and the
300 		 *       $currency_symbol
301 		 * = 2 - the sign string succeeds the quantity and the
302 		 *       $currency_symbol
303 		 * = 3 - the sign string precedes the $currency_symbol
304 		 * = 4 - the sign string succeeds the $currency_symbol
305                  *
306 		 */
307 
308 		tmpptr = dst;
309 
310 		while (pad_size-- > 0)
311 			PRINT(' ');
312 
313 		if (sign_posn == 0 && (flags & IS_NEGATIVE))
314 			PRINT('(');
315 
316 		if (cs_precedes == 1) {
317 			if (sign_posn == 1 || sign_posn == 3) {
318 				PRINTS(signstr);
319 				if (sep_by_space == 2)		/* XXX: ? */
320 					PRINT(' ');
321 			}
322 
323 			if (!(flags & SUPRESS_CURR_SYMBOL)) {
324 				PRINTS(currency_symbol);
325 
326 				if (sign_posn == 4) {
327 					if (sep_by_space == 2)
328 						PRINT(space_char);
329 					PRINTS(signstr);
330 					if (sep_by_space == 1)
331 						PRINT(' ');
332 				} else if (sep_by_space == 1)
333 					PRINT(space_char);
334 			}
335 		} else if (sign_posn == 1)
336 			PRINTS(signstr);
337 
338 		PRINTS(asciivalue);
339 
340 		if (cs_precedes == 0) {
341 			if (sign_posn == 3) {
342 				if (sep_by_space == 1)
343 					PRINT(' ');
344 				PRINTS(signstr);
345 			}
346 
347 			if (!(flags & SUPRESS_CURR_SYMBOL)) {
348 				if ((sign_posn == 3 && sep_by_space == 2)
349 				    || (sep_by_space == 1
350 				    && (sign_posn == 0
351 				    || sign_posn == 1
352 				    || sign_posn == 2
353 				    || sign_posn == 4)))
354 					PRINT(space_char);
355 				PRINTS(currency_symbol); /* XXX: len */
356 				if (sign_posn == 4) {
357 					if (sep_by_space == 2)
358 						PRINT(' ');
359 					PRINTS(signstr);
360 				}
361 			}
362 		}
363 
364 		if (sign_posn == 2) {
365 			if (sep_by_space == 2)
366 				PRINT(' ');
367 			PRINTS(signstr);
368 		}
369 
370 		if (sign_posn == 0 && (flags & IS_NEGATIVE))
371 			PRINT(')');
372 
373 		if (dst - tmpptr < width) {
374 			if (flags & LEFT_JUSTIFY) {
375 				while (dst - tmpptr < width)
376 					PRINT(' ');
377 			} else {
378 				pad_size = dst-tmpptr;
379 				memmove(tmpptr + width-pad_size, tmpptr,
380 				    pad_size);
381 				memset(tmpptr, ' ', width-pad_size);
382 				dst += width-pad_size;
383 			}
384 		}
385 	}
386 
387 	PRINT('\0');
388 	free(asciivalue);
389 	free(currency_symbol);
390 	return (dst - s - 1);	/* return size of put data except trailing '\0' */
391 
392 e2big_error:
393 	errno = E2BIG;
394 	goto end_error;
395 
396 format_error:
397 	errno = EINVAL;
398 
399 end_error:
400 	sverrno = errno;
401 	if (asciivalue != NULL)
402 		free(asciivalue);
403 	if (currency_symbol != NULL)
404 		free(currency_symbol);
405 	errno = sverrno;
406 	return (-1);
407 }
408 ssize_t
409 strfmon_l(char * __restrict s, size_t maxsize, locale_t loc, const char * __restrict format,
410     ...)
411 {
412 	size_t ret;
413 	va_list ap;
414 	va_start(ap, format);
415 	ret = vstrfmon_l(s, maxsize, loc, format, ap);
416 	va_end(ap);
417 	return ret;
418 }
419 
420 ssize_t
421 strfmon(char * __restrict s, size_t maxsize, const char * __restrict format,
422     ...)
423 {
424 	size_t ret;
425 	va_list ap;
426 	va_start(ap, format);
427 	ret = vstrfmon_l(s, maxsize, __get_locale(), format, ap);
428 	va_end(ap);
429 	return ret;
430 }
431 
432 
433 static void
434 __setup_vars(int flags, char *cs_precedes, char *sep_by_space,
435 		char *sign_posn, char **signstr) {
436 
437 	struct lconv *lc = localeconv();
438 
439 	if ((flags & IS_NEGATIVE) && (flags & USE_INTL_CURRENCY)) {
440 		*cs_precedes = lc->int_n_cs_precedes;
441 		*sep_by_space = lc->int_n_sep_by_space;
442 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_n_sign_posn;
443 		*signstr = (lc->negative_sign[0] == '\0') ? "-"
444 		    : lc->negative_sign;
445 	} else if (flags & USE_INTL_CURRENCY) {
446 		*cs_precedes = lc->int_p_cs_precedes;
447 		*sep_by_space = lc->int_p_sep_by_space;
448 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_p_sign_posn;
449 		*signstr = lc->positive_sign;
450 	} else if (flags & IS_NEGATIVE) {
451 		*cs_precedes = lc->n_cs_precedes;
452 		*sep_by_space = lc->n_sep_by_space;
453 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->n_sign_posn;
454 		*signstr = (lc->negative_sign[0] == '\0') ? "-"
455 		    : lc->negative_sign;
456 	} else {
457 		*cs_precedes = lc->p_cs_precedes;
458 		*sep_by_space = lc->p_sep_by_space;
459 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->p_sign_posn;
460 		*signstr = lc->positive_sign;
461 	}
462 
463 	/* Set defult values for unspecified information. */
464 	if (*cs_precedes != 0)
465 		*cs_precedes = 1;
466 	if (*sep_by_space == CHAR_MAX)
467 		*sep_by_space = 0;
468 	if (*sign_posn == CHAR_MAX)
469 		*sign_posn = 0;
470 }
471 
472 static int
473 __calc_left_pad(int flags, char *cur_symb) {
474 
475 	char cs_precedes, sep_by_space, sign_posn, *signstr;
476 	int left_chars = 0;
477 
478 	__setup_vars(flags, &cs_precedes, &sep_by_space, &sign_posn, &signstr);
479 
480 	if (cs_precedes != 0) {
481 		left_chars += strlen(cur_symb);
482 		if (sep_by_space != 0)
483 			left_chars++;
484 	}
485 
486 	switch (sign_posn) {
487 		case 1:
488 			left_chars += strlen(signstr);
489 			break;
490 		case 3:
491 		case 4:
492 			if (cs_precedes != 0)
493 				left_chars += strlen(signstr);
494 	}
495 	return (left_chars);
496 }
497 
498 static int
499 get_groups(int size, char *grouping) {
500 
501 	int	chars = 0;
502 
503 	if (*grouping == CHAR_MAX || *grouping <= 0)	/* no grouping ? */
504 		return (0);
505 
506 	while (size > (int)*grouping) {
507 		chars++;
508 		size -= (int)*grouping++;
509 		/* no more grouping ? */
510 		if (*grouping == CHAR_MAX)
511 			break;
512 		/* rest grouping with same value ? */
513 		if (*grouping == 0) {
514 			chars += (size - 1) / *(grouping - 1);
515 			break;
516 		}
517 	}
518 	return (chars);
519 }
520 
521 /* convert double to ASCII */
522 static char *
523 __format_grouped_double(double value, int *flags,
524 			int left_prec, int right_prec, int pad_char) {
525 
526 	char		*rslt;
527 	char		*avalue;
528 	int		avalue_size;
529 
530 	size_t		bufsize;
531 	char		*bufend;
532 
533 	int		padded;
534 
535 	struct lconv	*lc = localeconv();
536 	char		*grouping;
537 	char		decimal_point;
538 	char		thousands_sep;
539 
540 	int groups = 0;
541 
542 	grouping = lc->mon_grouping;
543 	decimal_point = *lc->mon_decimal_point;
544 	if (decimal_point == '\0')
545 		decimal_point = *lc->decimal_point;
546 	thousands_sep = *lc->mon_thousands_sep;
547 	if (thousands_sep == '\0')
548 		thousands_sep = *lc->thousands_sep;
549 
550 	/* fill left_prec with default value */
551 	if (left_prec == -1)
552 		left_prec = 0;
553 
554 	/* fill right_prec with default value */
555 	if (right_prec == -1) {
556                 if (*flags & USE_INTL_CURRENCY)
557                         right_prec = lc->int_frac_digits;
558                 else
559                         right_prec = lc->frac_digits;
560 
561 		if (right_prec == CHAR_MAX)	/* POSIX locale ? */
562 			right_prec = 2;
563 	}
564 
565 	if (*flags & NEED_GROUPING)
566 		left_prec += get_groups(left_prec, grouping);
567 
568 	/* convert to string */
569 	avalue_size = asprintf(&avalue, "%*.*f", left_prec + right_prec + 1,
570 	    right_prec, value);
571 	if (avalue_size < 0)
572 		return (NULL);
573 
574 	/* make sure that we've enough space for result string */
575 	bufsize = avalue_size * 2 + 1;
576 	rslt = calloc(1, bufsize);
577 	if (rslt == NULL) {
578 		free(avalue);
579 		return (NULL);
580 	}
581 	bufend = rslt + bufsize - 1;	/* reserve space for trailing '\0' */
582 
583 	/* skip spaces at beginning */
584 	padded = 0;
585 	while (avalue[padded] == ' ') {
586 		padded++;
587 		avalue_size--;
588 	}
589 
590 	if (right_prec > 0) {
591 		bufend -= right_prec;
592 		memcpy(bufend, avalue + avalue_size+padded-right_prec,
593 		    right_prec);
594 		*--bufend = decimal_point;
595 		avalue_size -= (right_prec + 1);
596 	}
597 
598 	if ((*flags & NEED_GROUPING) &&
599 	    thousands_sep != '\0' &&	/* XXX: need investigation */
600 	    *grouping != CHAR_MAX &&
601 	    *grouping > 0) {
602 		while (avalue_size > (int)*grouping) {
603 			GRPCPY(*grouping);
604 			GRPSEP;
605 			grouping++;
606 
607 			/* no more grouping ? */
608 			if (*grouping == CHAR_MAX)
609 				break;
610 
611 			/* rest grouping with same value ? */
612 			if (*grouping == 0) {
613 				grouping--;
614 				while (avalue_size > *grouping) {
615 					GRPCPY(*grouping);
616 					GRPSEP;
617 				}
618 			}
619 		}
620 		if (avalue_size != 0)
621 			GRPCPY(avalue_size);
622 		padded -= groups;
623 
624 	} else {
625 		bufend -= avalue_size;
626 		memcpy(bufend, avalue+padded, avalue_size);
627 		if (right_prec == 0)
628 			padded--;	/* decrease assumed $decimal_point */
629 	}
630 
631 	/* do padding with pad_char */
632 	if (padded > 0) {
633 		bufend -= padded;
634 		memset(bufend, pad_char, padded);
635 	}
636 
637 	bufsize = bufsize - (bufend - rslt) + 1;
638 	memmove(rslt, bufend, bufsize);
639 	free(avalue);
640 	return (rslt);
641 }
642