xref: /freebsd/lib/libc/stdlib/strfmon.c (revision a0409676120c1e558d0ade943019934e0f15118d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2001 Alexey Zelkin <phantom@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Copyright (c) 2011 The FreeBSD Foundation
8  * All rights reserved.
9  * Portions of this software were developed by David Chisnall
10  * under sponsorship from the FreeBSD Foundation.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  */
34 
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #include <sys/types.h>
39 #include <ctype.h>
40 #include <errno.h>
41 #include <limits.h>
42 #include <locale.h>
43 #include <monetary.h>
44 #include <stdarg.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include "xlocale_private.h"
49 
50 /* internal flags */
51 #define	NEED_GROUPING		0x01	/* print digits grouped (default) */
52 #define	SIGN_POSN_USED		0x02	/* '+' or '(' usage flag */
53 #define	LOCALE_POSN		0x04	/* use locale defined +/- (default) */
54 #define	PARENTH_POSN		0x08	/* enclose negative amount in () */
55 #define	SUPRESS_CURR_SYMBOL	0x10	/* suppress the currency from output */
56 #define	LEFT_JUSTIFY		0x20	/* left justify */
57 #define	USE_INTL_CURRENCY	0x40	/* use international currency symbol */
58 #define IS_NEGATIVE		0x80	/* is argument value negative ? */
59 
60 /* internal macros */
61 #define PRINT(CH) do {						\
62 	if (dst >= s + maxsize) 				\
63 		goto e2big_error;				\
64 	*dst++ = CH;						\
65 } while (0)
66 
67 #define PRINTS(STR) do {					\
68 	char *tmps = STR;					\
69 	while (*tmps != '\0')					\
70 		PRINT(*tmps++);					\
71 } while (0)
72 
73 #define GET_NUMBER(VAR)	do {					\
74 	VAR = 0;						\
75 	while (isdigit((unsigned char)*fmt)) {			\
76 		if (VAR > INT_MAX / 10)				\
77 			goto e2big_error;			\
78 		VAR *= 10;					\
79 		VAR += *fmt - '0';				\
80 		if (VAR < 0)					\
81 			goto e2big_error;			\
82 		fmt++;						\
83 	}							\
84 } while (0)
85 
86 #define GRPCPY(howmany) do {					\
87 	int i = howmany;					\
88 	while (i-- > 0) {					\
89 		avalue_size--;					\
90 		*--bufend = *(avalue+avalue_size+padded);	\
91 	}							\
92 } while (0)
93 
94 #define GRPSEP do {						\
95 	bufend -= thousands_sep_size;				\
96 	memcpy(bufend, thousands_sep, thousands_sep_size);	\
97 	groups++;						\
98 } while (0)
99 
100 static void __setup_vars(int, char *, char *, char *, char **);
101 static int __calc_left_pad(int, char *);
102 static char *__format_grouped_double(double, int *, int, int, int);
103 
104 static ssize_t
105 vstrfmon_l(char * __restrict s, size_t maxsize, locale_t loc,
106 		const char * __restrict format, va_list ap)
107 {
108 	char 		*dst;		/* output destination pointer */
109 	const char 	*fmt;		/* current format poistion pointer */
110 	struct lconv 	*lc;		/* pointer to lconv structure */
111 	char		*asciivalue;	/* formatted double pointer */
112 
113 	int		flags;		/* formatting options */
114 	int		pad_char;	/* padding character */
115 	int		pad_size;	/* pad size */
116 	int		width;		/* field width */
117 	int		left_prec;	/* left precision */
118 	int		right_prec;	/* right precision */
119 	double		value;		/* just value */
120 	char		space_char = ' '; /* space after currency */
121 
122 	char		cs_precedes,	/* values gathered from struct lconv */
123 			sep_by_space,
124 			sign_posn,
125 			*signstr,
126 			*currency_symbol;
127 
128 	char		*tmpptr;	/* temporary vars */
129 	int		sverrno;
130 	FIX_LOCALE(loc);
131 
132 
133 	lc = localeconv_l(loc);
134 	dst = s;
135 	fmt = format;
136 	asciivalue = NULL;
137 	currency_symbol = NULL;
138 	pad_size = 0;
139 
140 	while (*fmt) {
141 		/* pass nonformating characters AS IS */
142 		if (*fmt != '%')
143 			goto literal;
144 
145 		/* '%' found ! */
146 
147 		/* "%%" mean just '%' */
148 		if (*(fmt+1) == '%') {
149 			fmt++;
150 	literal:
151 			PRINT(*fmt++);
152 			continue;
153 		}
154 
155 		/* set up initial values */
156 		flags = (NEED_GROUPING|LOCALE_POSN);
157 		pad_char = ' ';		/* padding character is "space" */
158 		left_prec = -1;		/* no left precision specified */
159 		right_prec = -1;	/* no right precision specified */
160 		width = -1;		/* no width specified */
161 		value = 0;		/* we have no value to print now */
162 
163 		/* Flags */
164 		while (1) {
165 			switch (*++fmt) {
166 				case '=':	/* fill character */
167 					pad_char = *++fmt;
168 					if (pad_char == '\0')
169 						goto format_error;
170 					continue;
171 				case '^':	/* not group currency  */
172 					flags &= ~(NEED_GROUPING);
173 					continue;
174 				case '+':	/* use locale defined signs */
175 					if (flags & SIGN_POSN_USED)
176 						goto format_error;
177 					flags |= (SIGN_POSN_USED|LOCALE_POSN);
178 					continue;
179 				case '(':	/* enclose negatives with () */
180 					if (flags & SIGN_POSN_USED)
181 						goto format_error;
182 					flags |= (SIGN_POSN_USED|PARENTH_POSN);
183 					continue;
184 				case '!':	/* suppress currency symbol */
185 					flags |= SUPRESS_CURR_SYMBOL;
186 					continue;
187 				case '-':	/* alignment (left)  */
188 					flags |= LEFT_JUSTIFY;
189 					continue;
190 				default:
191 					break;
192 			}
193 			break;
194 		}
195 
196 		/* field Width */
197 		if (isdigit((unsigned char)*fmt)) {
198 			GET_NUMBER(width);
199 			/* Do we have enough space to put number with
200 			 * required width ?
201 			 */
202 			if ((unsigned int)width >= maxsize - (dst - s))
203 				goto e2big_error;
204 		}
205 
206 		/* Left precision */
207 		if (*fmt == '#') {
208 			if (!isdigit((unsigned char)*++fmt))
209 				goto format_error;
210 			GET_NUMBER(left_prec);
211 			if ((unsigned int)left_prec >= maxsize - (dst - s))
212 				goto e2big_error;
213 		}
214 
215 		/* Right precision */
216 		if (*fmt == '.') {
217 			if (!isdigit((unsigned char)*++fmt))
218 				goto format_error;
219 			GET_NUMBER(right_prec);
220 			if ((unsigned int)right_prec >= maxsize - (dst - s) -
221 			    left_prec)
222 				goto e2big_error;
223 		}
224 
225 		/* Conversion Characters */
226 		switch (*fmt++) {
227 			case 'i':	/* use internaltion currency format */
228 				flags |= USE_INTL_CURRENCY;
229 				break;
230 			case 'n':	/* use national currency format */
231 				flags &= ~(USE_INTL_CURRENCY);
232 				break;
233 			default:	/* required character is missing or
234 					   premature EOS */
235 				goto format_error;
236 		}
237 
238 		if (currency_symbol != NULL)
239 			free(currency_symbol);
240 		if (flags & USE_INTL_CURRENCY) {
241 			currency_symbol = strdup(lc->int_curr_symbol);
242 			if (currency_symbol != NULL)
243 				space_char = *(currency_symbol+3);
244 		} else
245 			currency_symbol = strdup(lc->currency_symbol);
246 
247 		if (currency_symbol == NULL)
248 			goto end_error;			/* ENOMEM. */
249 
250 		/* value itself */
251 		value = va_arg(ap, double);
252 
253 		/* detect sign */
254 		if (value < 0) {
255 			flags |= IS_NEGATIVE;
256 			value = -value;
257 		}
258 
259 		/* fill left_prec with amount of padding chars */
260 		if (left_prec >= 0) {
261 			pad_size = __calc_left_pad((flags ^ IS_NEGATIVE),
262 							currency_symbol) -
263 				   __calc_left_pad(flags, currency_symbol);
264 			if (pad_size < 0)
265 				pad_size = 0;
266 		}
267 
268 		if (asciivalue != NULL)
269 			free(asciivalue);
270 		asciivalue = __format_grouped_double(value, &flags,
271 				left_prec, right_prec, pad_char);
272 		if (asciivalue == NULL)
273 			goto end_error;		/* errno already set     */
274 						/* to ENOMEM by malloc() */
275 
276 		/* set some variables for later use */
277 		__setup_vars(flags, &cs_precedes, &sep_by_space,
278 				&sign_posn, &signstr);
279 
280 		/*
281 		 * Description of some LC_MONETARY's values:
282 		 *
283 		 * p_cs_precedes & n_cs_precedes
284 		 *
285 		 * = 1 - $currency_symbol precedes the value
286 		 *       for a monetary quantity with a non-negative value
287 		 * = 0 - symbol succeeds the value
288 		 *
289 		 * p_sep_by_space & n_sep_by_space
290                  *
291 		 * = 0 - no space separates $currency_symbol
292 		 *       from the value for a monetary quantity with a
293 		 *	 non-negative value
294 		 * = 1 - space separates the symbol from the value
295 		 * = 2 - space separates the symbol and the sign string,
296 		 *       if adjacent.
297                  *
298 		 * p_sign_posn & n_sign_posn
299                  *
300 		 * = 0 - parentheses enclose the quantity and the
301 		 *	 $currency_symbol
302 		 * = 1 - the sign string precedes the quantity and the
303 		 *       $currency_symbol
304 		 * = 2 - the sign string succeeds the quantity and the
305 		 *       $currency_symbol
306 		 * = 3 - the sign string precedes the $currency_symbol
307 		 * = 4 - the sign string succeeds the $currency_symbol
308                  *
309 		 */
310 
311 		tmpptr = dst;
312 
313 		while (pad_size-- > 0)
314 			PRINT(' ');
315 
316 		if (sign_posn == 0 && (flags & IS_NEGATIVE))
317 			PRINT('(');
318 
319 		if (cs_precedes == 1) {
320 			if (sign_posn == 1 || sign_posn == 3) {
321 				PRINTS(signstr);
322 				if (sep_by_space == 2)		/* XXX: ? */
323 					PRINT(' ');
324 			}
325 
326 			if (!(flags & SUPRESS_CURR_SYMBOL)) {
327 				PRINTS(currency_symbol);
328 
329 				if (sign_posn == 4) {
330 					if (sep_by_space == 2)
331 						PRINT(space_char);
332 					PRINTS(signstr);
333 					if (sep_by_space == 1)
334 						PRINT(' ');
335 				} else if (sep_by_space == 1)
336 					PRINT(space_char);
337 			}
338 		} else if (sign_posn == 1)
339 			PRINTS(signstr);
340 
341 		PRINTS(asciivalue);
342 
343 		if (cs_precedes == 0) {
344 			if (sign_posn == 3) {
345 				if (sep_by_space == 1)
346 					PRINT(' ');
347 				PRINTS(signstr);
348 			}
349 
350 			if (!(flags & SUPRESS_CURR_SYMBOL)) {
351 				if ((sign_posn == 3 && sep_by_space == 2)
352 				    || (sep_by_space == 1
353 				    && (sign_posn == 0
354 				    || sign_posn == 1
355 				    || sign_posn == 2
356 				    || sign_posn == 4)))
357 					PRINT(space_char);
358 				PRINTS(currency_symbol); /* XXX: len */
359 				if (sign_posn == 4) {
360 					if (sep_by_space == 2)
361 						PRINT(' ');
362 					PRINTS(signstr);
363 				}
364 			}
365 		}
366 
367 		if (sign_posn == 2) {
368 			if (sep_by_space == 2)
369 				PRINT(' ');
370 			PRINTS(signstr);
371 		}
372 
373 		if (sign_posn == 0 && (flags & IS_NEGATIVE))
374 			PRINT(')');
375 
376 		if (dst - tmpptr < width) {
377 			if (flags & LEFT_JUSTIFY) {
378 				while (dst - tmpptr < width)
379 					PRINT(' ');
380 			} else {
381 				pad_size = dst-tmpptr;
382 				memmove(tmpptr + width-pad_size, tmpptr,
383 				    pad_size);
384 				memset(tmpptr, ' ', width-pad_size);
385 				dst += width-pad_size;
386 			}
387 		}
388 	}
389 
390 	PRINT('\0');
391 	free(asciivalue);
392 	free(currency_symbol);
393 	return (dst - s - 1);	/* return size of put data except trailing '\0' */
394 
395 e2big_error:
396 	errno = E2BIG;
397 	goto end_error;
398 
399 format_error:
400 	errno = EINVAL;
401 
402 end_error:
403 	sverrno = errno;
404 	if (asciivalue != NULL)
405 		free(asciivalue);
406 	if (currency_symbol != NULL)
407 		free(currency_symbol);
408 	errno = sverrno;
409 	return (-1);
410 }
411 ssize_t
412 strfmon_l(char * __restrict s, size_t maxsize, locale_t loc, const char * __restrict format,
413     ...)
414 {
415 	size_t ret;
416 	va_list ap;
417 	va_start(ap, format);
418 	ret = vstrfmon_l(s, maxsize, loc, format, ap);
419 	va_end(ap);
420 	return ret;
421 }
422 
423 ssize_t
424 strfmon(char * __restrict s, size_t maxsize, const char * __restrict format,
425     ...)
426 {
427 	size_t ret;
428 	va_list ap;
429 	va_start(ap, format);
430 	ret = vstrfmon_l(s, maxsize, __get_locale(), format, ap);
431 	va_end(ap);
432 	return ret;
433 }
434 
435 
436 static void
437 __setup_vars(int flags, char *cs_precedes, char *sep_by_space,
438 		char *sign_posn, char **signstr) {
439 
440 	struct lconv *lc = localeconv();
441 
442 	if ((flags & IS_NEGATIVE) && (flags & USE_INTL_CURRENCY)) {
443 		*cs_precedes = lc->int_n_cs_precedes;
444 		*sep_by_space = lc->int_n_sep_by_space;
445 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_n_sign_posn;
446 		*signstr = (lc->negative_sign[0] == '\0') ? "-"
447 		    : lc->negative_sign;
448 	} else if (flags & USE_INTL_CURRENCY) {
449 		*cs_precedes = lc->int_p_cs_precedes;
450 		*sep_by_space = lc->int_p_sep_by_space;
451 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_p_sign_posn;
452 		*signstr = lc->positive_sign;
453 	} else if (flags & IS_NEGATIVE) {
454 		*cs_precedes = lc->n_cs_precedes;
455 		*sep_by_space = lc->n_sep_by_space;
456 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->n_sign_posn;
457 		*signstr = (lc->negative_sign[0] == '\0') ? "-"
458 		    : lc->negative_sign;
459 	} else {
460 		*cs_precedes = lc->p_cs_precedes;
461 		*sep_by_space = lc->p_sep_by_space;
462 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->p_sign_posn;
463 		*signstr = lc->positive_sign;
464 	}
465 
466 	/* Set defult values for unspecified information. */
467 	if (*cs_precedes != 0)
468 		*cs_precedes = 1;
469 	if (*sep_by_space == CHAR_MAX)
470 		*sep_by_space = 0;
471 	if (*sign_posn == CHAR_MAX)
472 		*sign_posn = 0;
473 }
474 
475 static int
476 __calc_left_pad(int flags, char *cur_symb) {
477 
478 	char cs_precedes, sep_by_space, sign_posn, *signstr;
479 	int left_chars = 0;
480 
481 	__setup_vars(flags, &cs_precedes, &sep_by_space, &sign_posn, &signstr);
482 
483 	if (cs_precedes != 0) {
484 		left_chars += strlen(cur_symb);
485 		if (sep_by_space != 0)
486 			left_chars++;
487 	}
488 
489 	switch (sign_posn) {
490 		case 1:
491 			left_chars += strlen(signstr);
492 			break;
493 		case 3:
494 		case 4:
495 			if (cs_precedes != 0)
496 				left_chars += strlen(signstr);
497 	}
498 	return (left_chars);
499 }
500 
501 static int
502 get_groups(int size, char *grouping) {
503 
504 	int	chars = 0;
505 
506 	if (*grouping == CHAR_MAX || *grouping <= 0)	/* no grouping ? */
507 		return (0);
508 
509 	while (size > (int)*grouping) {
510 		chars++;
511 		size -= (int)*grouping++;
512 		/* no more grouping ? */
513 		if (*grouping == CHAR_MAX)
514 			break;
515 		/* rest grouping with same value ? */
516 		if (*grouping == 0) {
517 			chars += (size - 1) / *(grouping - 1);
518 			break;
519 		}
520 	}
521 	return (chars);
522 }
523 
524 /* convert double to locale-encoded string */
525 static char *
526 __format_grouped_double(double value, int *flags,
527 			int left_prec, int right_prec, int pad_char) {
528 
529 	char		*rslt;
530 	char		*avalue;
531 	int		avalue_size;
532 
533 	size_t		bufsize;
534 	char		*bufend;
535 
536 	int		padded;
537 
538 	struct lconv	*lc = localeconv();
539 	char		*grouping;
540 	const char	*decimal_point;
541 	const char	*thousands_sep;
542 	size_t		decimal_point_size;
543 	size_t		thousands_sep_size;
544 
545 	int groups = 0;
546 
547 	grouping = lc->mon_grouping;
548 	decimal_point = lc->mon_decimal_point;
549 	if (*decimal_point == '\0')
550 		decimal_point = lc->decimal_point;
551 	thousands_sep = lc->mon_thousands_sep;
552 	if (*thousands_sep == '\0')
553 		thousands_sep = lc->thousands_sep;
554 
555 	decimal_point_size = strlen(decimal_point);
556 	thousands_sep_size = strlen(thousands_sep);
557 
558 	/* fill left_prec with default value */
559 	if (left_prec == -1)
560 		left_prec = 0;
561 
562 	/* fill right_prec with default value */
563 	if (right_prec == -1) {
564                 if (*flags & USE_INTL_CURRENCY)
565                         right_prec = lc->int_frac_digits;
566                 else
567                         right_prec = lc->frac_digits;
568 
569 		if (right_prec == CHAR_MAX)	/* POSIX locale ? */
570 			right_prec = 2;
571 	}
572 
573 	if (*flags & NEED_GROUPING)
574 		left_prec += get_groups(left_prec, grouping);
575 
576 	/* convert to string */
577 	avalue_size = asprintf(&avalue, "%*.*f", left_prec + right_prec + 1,
578 	    right_prec, value);
579 	if (avalue_size < 0)
580 		return (NULL);
581 
582 	/* make sure that we've enough space for result string */
583 	bufsize = avalue_size * (1 + thousands_sep_size) + decimal_point_size +
584 	    1;
585 	rslt = calloc(1, bufsize);
586 	if (rslt == NULL) {
587 		free(avalue);
588 		return (NULL);
589 	}
590 	bufend = rslt + bufsize - 1;	/* reserve space for trailing '\0' */
591 
592 	/* skip spaces at beginning */
593 	padded = 0;
594 	while (avalue[padded] == ' ') {
595 		padded++;
596 		avalue_size--;
597 	}
598 
599 	if (right_prec > 0) {
600 		bufend -= right_prec;
601 		memcpy(bufend, avalue + avalue_size+padded-right_prec,
602 		    right_prec);
603 		bufend -= decimal_point_size;
604 		memcpy(bufend, decimal_point, decimal_point_size);
605 		avalue_size -= (right_prec + 1);
606 	}
607 
608 	if ((*flags & NEED_GROUPING) &&
609 	    thousands_sep_size > 0 &&	/* XXX: need investigation */
610 	    *grouping != CHAR_MAX &&
611 	    *grouping > 0) {
612 		while (avalue_size > (int)*grouping) {
613 			GRPCPY(*grouping);
614 			GRPSEP;
615 			grouping++;
616 
617 			/* no more grouping ? */
618 			if (*grouping == CHAR_MAX)
619 				break;
620 
621 			/* rest grouping with same value ? */
622 			if (*grouping == 0) {
623 				grouping--;
624 				while (avalue_size > *grouping) {
625 					GRPCPY(*grouping);
626 					GRPSEP;
627 				}
628 			}
629 		}
630 		if (avalue_size != 0)
631 			GRPCPY(avalue_size);
632 		padded -= groups;
633 
634 	} else {
635 		bufend -= avalue_size;
636 		memcpy(bufend, avalue+padded, avalue_size);
637 		/* decrease assumed $decimal_point */
638 		if (right_prec == 0)
639 			padded -= decimal_point_size;
640 	}
641 
642 	/* do padding with pad_char */
643 	if (padded > 0) {
644 		bufend -= padded;
645 		memset(bufend, pad_char, padded);
646 	}
647 
648 	bufsize = rslt + bufsize - bufend;
649 	memmove(rslt, bufend, bufsize);
650 	free(avalue);
651 	return (rslt);
652 }
653