xref: /freebsd/lib/libc/stdlib/strfmon.c (revision 4f52dfbb8d6c4d446500c5b097e3806ec219fbd4)
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;				\
96 	groups++;						\
97 } while (0)
98 
99 static void __setup_vars(int, char *, char *, char *, char **);
100 static int __calc_left_pad(int, char *);
101 static char *__format_grouped_double(double, int *, int, int, int);
102 
103 static ssize_t
104 vstrfmon_l(char * __restrict s, size_t maxsize, locale_t loc,
105 		const char * __restrict format, va_list ap)
106 {
107 	char 		*dst;		/* output destination pointer */
108 	const char 	*fmt;		/* current format poistion pointer */
109 	struct lconv 	*lc;		/* pointer to lconv structure */
110 	char		*asciivalue;	/* formatted double pointer */
111 
112 	int		flags;		/* formatting options */
113 	int		pad_char;	/* padding character */
114 	int		pad_size;	/* pad size */
115 	int		width;		/* field width */
116 	int		left_prec;	/* left precision */
117 	int		right_prec;	/* right precision */
118 	double		value;		/* just value */
119 	char		space_char = ' '; /* space after currency */
120 
121 	char		cs_precedes,	/* values gathered from struct lconv */
122 			sep_by_space,
123 			sign_posn,
124 			*signstr,
125 			*currency_symbol;
126 
127 	char		*tmpptr;	/* temporary vars */
128 	int		sverrno;
129 	FIX_LOCALE(loc);
130 
131 
132 	lc = localeconv_l(loc);
133 	dst = s;
134 	fmt = format;
135 	asciivalue = NULL;
136 	currency_symbol = NULL;
137 	pad_size = 0;
138 
139 	while (*fmt) {
140 		/* pass nonformating characters AS IS */
141 		if (*fmt != '%')
142 			goto literal;
143 
144 		/* '%' found ! */
145 
146 		/* "%%" mean just '%' */
147 		if (*(fmt+1) == '%') {
148 			fmt++;
149 	literal:
150 			PRINT(*fmt++);
151 			continue;
152 		}
153 
154 		/* set up initial values */
155 		flags = (NEED_GROUPING|LOCALE_POSN);
156 		pad_char = ' ';		/* padding character is "space" */
157 		left_prec = -1;		/* no left precision specified */
158 		right_prec = -1;	/* no right precision specified */
159 		width = -1;		/* no width specified */
160 		value = 0;		/* we have no value to print now */
161 
162 		/* Flags */
163 		while (1) {
164 			switch (*++fmt) {
165 				case '=':	/* fill character */
166 					pad_char = *++fmt;
167 					if (pad_char == '\0')
168 						goto format_error;
169 					continue;
170 				case '^':	/* not group currency  */
171 					flags &= ~(NEED_GROUPING);
172 					continue;
173 				case '+':	/* use locale defined signs */
174 					if (flags & SIGN_POSN_USED)
175 						goto format_error;
176 					flags |= (SIGN_POSN_USED|LOCALE_POSN);
177 					continue;
178 				case '(':	/* enclose negatives with () */
179 					if (flags & SIGN_POSN_USED)
180 						goto format_error;
181 					flags |= (SIGN_POSN_USED|PARENTH_POSN);
182 					continue;
183 				case '!':	/* suppress currency symbol */
184 					flags |= SUPRESS_CURR_SYMBOL;
185 					continue;
186 				case '-':	/* alignment (left)  */
187 					flags |= LEFT_JUSTIFY;
188 					continue;
189 				default:
190 					break;
191 			}
192 			break;
193 		}
194 
195 		/* field Width */
196 		if (isdigit((unsigned char)*fmt)) {
197 			GET_NUMBER(width);
198 			/* Do we have enough space to put number with
199 			 * required width ?
200 			 */
201 			if ((unsigned int)width >= maxsize - (dst - s))
202 				goto e2big_error;
203 		}
204 
205 		/* Left precision */
206 		if (*fmt == '#') {
207 			if (!isdigit((unsigned char)*++fmt))
208 				goto format_error;
209 			GET_NUMBER(left_prec);
210 			if ((unsigned int)left_prec >= maxsize - (dst - s))
211 				goto e2big_error;
212 		}
213 
214 		/* Right precision */
215 		if (*fmt == '.') {
216 			if (!isdigit((unsigned char)*++fmt))
217 				goto format_error;
218 			GET_NUMBER(right_prec);
219 			if ((unsigned int)right_prec >= maxsize - (dst - s) -
220 			    left_prec)
221 				goto e2big_error;
222 		}
223 
224 		/* Conversion Characters */
225 		switch (*fmt++) {
226 			case 'i':	/* use internaltion currency format */
227 				flags |= USE_INTL_CURRENCY;
228 				break;
229 			case 'n':	/* use national currency format */
230 				flags &= ~(USE_INTL_CURRENCY);
231 				break;
232 			default:	/* required character is missing or
233 					   premature EOS */
234 				goto format_error;
235 		}
236 
237 		if (currency_symbol != NULL)
238 			free(currency_symbol);
239 		if (flags & USE_INTL_CURRENCY) {
240 			currency_symbol = strdup(lc->int_curr_symbol);
241 			if (currency_symbol != NULL)
242 				space_char = *(currency_symbol+3);
243 		} else
244 			currency_symbol = strdup(lc->currency_symbol);
245 
246 		if (currency_symbol == NULL)
247 			goto end_error;			/* ENOMEM. */
248 
249 		/* value itself */
250 		value = va_arg(ap, double);
251 
252 		/* detect sign */
253 		if (value < 0) {
254 			flags |= IS_NEGATIVE;
255 			value = -value;
256 		}
257 
258 		/* fill left_prec with amount of padding chars */
259 		if (left_prec >= 0) {
260 			pad_size = __calc_left_pad((flags ^ IS_NEGATIVE),
261 							currency_symbol) -
262 				   __calc_left_pad(flags, currency_symbol);
263 			if (pad_size < 0)
264 				pad_size = 0;
265 		}
266 
267 		if (asciivalue != NULL)
268 			free(asciivalue);
269 		asciivalue = __format_grouped_double(value, &flags,
270 				left_prec, right_prec, pad_char);
271 		if (asciivalue == NULL)
272 			goto end_error;		/* errno already set     */
273 						/* to ENOMEM by malloc() */
274 
275 		/* set some variables for later use */
276 		__setup_vars(flags, &cs_precedes, &sep_by_space,
277 				&sign_posn, &signstr);
278 
279 		/*
280 		 * Description of some LC_MONETARY's values:
281 		 *
282 		 * p_cs_precedes & n_cs_precedes
283 		 *
284 		 * = 1 - $currency_symbol precedes the value
285 		 *       for a monetary quantity with a non-negative value
286 		 * = 0 - symbol succeeds the value
287 		 *
288 		 * p_sep_by_space & n_sep_by_space
289                  *
290 		 * = 0 - no space separates $currency_symbol
291 		 *       from the value for a monetary quantity with a
292 		 *	 non-negative value
293 		 * = 1 - space separates the symbol from the value
294 		 * = 2 - space separates the symbol and the sign string,
295 		 *       if adjacent.
296                  *
297 		 * p_sign_posn & n_sign_posn
298                  *
299 		 * = 0 - parentheses enclose the quantity and the
300 		 *	 $currency_symbol
301 		 * = 1 - the sign string precedes the quantity and the
302 		 *       $currency_symbol
303 		 * = 2 - the sign string succeeds the quantity and the
304 		 *       $currency_symbol
305 		 * = 3 - the sign string precedes the $currency_symbol
306 		 * = 4 - the sign string succeeds the $currency_symbol
307                  *
308 		 */
309 
310 		tmpptr = dst;
311 
312 		while (pad_size-- > 0)
313 			PRINT(' ');
314 
315 		if (sign_posn == 0 && (flags & IS_NEGATIVE))
316 			PRINT('(');
317 
318 		if (cs_precedes == 1) {
319 			if (sign_posn == 1 || sign_posn == 3) {
320 				PRINTS(signstr);
321 				if (sep_by_space == 2)		/* XXX: ? */
322 					PRINT(' ');
323 			}
324 
325 			if (!(flags & SUPRESS_CURR_SYMBOL)) {
326 				PRINTS(currency_symbol);
327 
328 				if (sign_posn == 4) {
329 					if (sep_by_space == 2)
330 						PRINT(space_char);
331 					PRINTS(signstr);
332 					if (sep_by_space == 1)
333 						PRINT(' ');
334 				} else if (sep_by_space == 1)
335 					PRINT(space_char);
336 			}
337 		} else if (sign_posn == 1)
338 			PRINTS(signstr);
339 
340 		PRINTS(asciivalue);
341 
342 		if (cs_precedes == 0) {
343 			if (sign_posn == 3) {
344 				if (sep_by_space == 1)
345 					PRINT(' ');
346 				PRINTS(signstr);
347 			}
348 
349 			if (!(flags & SUPRESS_CURR_SYMBOL)) {
350 				if ((sign_posn == 3 && sep_by_space == 2)
351 				    || (sep_by_space == 1
352 				    && (sign_posn == 0
353 				    || sign_posn == 1
354 				    || sign_posn == 2
355 				    || sign_posn == 4)))
356 					PRINT(space_char);
357 				PRINTS(currency_symbol); /* XXX: len */
358 				if (sign_posn == 4) {
359 					if (sep_by_space == 2)
360 						PRINT(' ');
361 					PRINTS(signstr);
362 				}
363 			}
364 		}
365 
366 		if (sign_posn == 2) {
367 			if (sep_by_space == 2)
368 				PRINT(' ');
369 			PRINTS(signstr);
370 		}
371 
372 		if (sign_posn == 0 && (flags & IS_NEGATIVE))
373 			PRINT(')');
374 
375 		if (dst - tmpptr < width) {
376 			if (flags & LEFT_JUSTIFY) {
377 				while (dst - tmpptr < width)
378 					PRINT(' ');
379 			} else {
380 				pad_size = dst-tmpptr;
381 				memmove(tmpptr + width-pad_size, tmpptr,
382 				    pad_size);
383 				memset(tmpptr, ' ', width-pad_size);
384 				dst += width-pad_size;
385 			}
386 		}
387 	}
388 
389 	PRINT('\0');
390 	free(asciivalue);
391 	free(currency_symbol);
392 	return (dst - s - 1);	/* return size of put data except trailing '\0' */
393 
394 e2big_error:
395 	errno = E2BIG;
396 	goto end_error;
397 
398 format_error:
399 	errno = EINVAL;
400 
401 end_error:
402 	sverrno = errno;
403 	if (asciivalue != NULL)
404 		free(asciivalue);
405 	if (currency_symbol != NULL)
406 		free(currency_symbol);
407 	errno = sverrno;
408 	return (-1);
409 }
410 ssize_t
411 strfmon_l(char * __restrict s, size_t maxsize, locale_t loc, const char * __restrict format,
412     ...)
413 {
414 	size_t ret;
415 	va_list ap;
416 	va_start(ap, format);
417 	ret = vstrfmon_l(s, maxsize, loc, format, ap);
418 	va_end(ap);
419 	return ret;
420 }
421 
422 ssize_t
423 strfmon(char * __restrict s, size_t maxsize, const char * __restrict format,
424     ...)
425 {
426 	size_t ret;
427 	va_list ap;
428 	va_start(ap, format);
429 	ret = vstrfmon_l(s, maxsize, __get_locale(), format, ap);
430 	va_end(ap);
431 	return ret;
432 }
433 
434 
435 static void
436 __setup_vars(int flags, char *cs_precedes, char *sep_by_space,
437 		char *sign_posn, char **signstr) {
438 
439 	struct lconv *lc = localeconv();
440 
441 	if ((flags & IS_NEGATIVE) && (flags & USE_INTL_CURRENCY)) {
442 		*cs_precedes = lc->int_n_cs_precedes;
443 		*sep_by_space = lc->int_n_sep_by_space;
444 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_n_sign_posn;
445 		*signstr = (lc->negative_sign[0] == '\0') ? "-"
446 		    : lc->negative_sign;
447 	} else if (flags & USE_INTL_CURRENCY) {
448 		*cs_precedes = lc->int_p_cs_precedes;
449 		*sep_by_space = lc->int_p_sep_by_space;
450 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_p_sign_posn;
451 		*signstr = lc->positive_sign;
452 	} else if (flags & IS_NEGATIVE) {
453 		*cs_precedes = lc->n_cs_precedes;
454 		*sep_by_space = lc->n_sep_by_space;
455 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->n_sign_posn;
456 		*signstr = (lc->negative_sign[0] == '\0') ? "-"
457 		    : lc->negative_sign;
458 	} else {
459 		*cs_precedes = lc->p_cs_precedes;
460 		*sep_by_space = lc->p_sep_by_space;
461 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->p_sign_posn;
462 		*signstr = lc->positive_sign;
463 	}
464 
465 	/* Set defult values for unspecified information. */
466 	if (*cs_precedes != 0)
467 		*cs_precedes = 1;
468 	if (*sep_by_space == CHAR_MAX)
469 		*sep_by_space = 0;
470 	if (*sign_posn == CHAR_MAX)
471 		*sign_posn = 0;
472 }
473 
474 static int
475 __calc_left_pad(int flags, char *cur_symb) {
476 
477 	char cs_precedes, sep_by_space, sign_posn, *signstr;
478 	int left_chars = 0;
479 
480 	__setup_vars(flags, &cs_precedes, &sep_by_space, &sign_posn, &signstr);
481 
482 	if (cs_precedes != 0) {
483 		left_chars += strlen(cur_symb);
484 		if (sep_by_space != 0)
485 			left_chars++;
486 	}
487 
488 	switch (sign_posn) {
489 		case 1:
490 			left_chars += strlen(signstr);
491 			break;
492 		case 3:
493 		case 4:
494 			if (cs_precedes != 0)
495 				left_chars += strlen(signstr);
496 	}
497 	return (left_chars);
498 }
499 
500 static int
501 get_groups(int size, char *grouping) {
502 
503 	int	chars = 0;
504 
505 	if (*grouping == CHAR_MAX || *grouping <= 0)	/* no grouping ? */
506 		return (0);
507 
508 	while (size > (int)*grouping) {
509 		chars++;
510 		size -= (int)*grouping++;
511 		/* no more grouping ? */
512 		if (*grouping == CHAR_MAX)
513 			break;
514 		/* rest grouping with same value ? */
515 		if (*grouping == 0) {
516 			chars += (size - 1) / *(grouping - 1);
517 			break;
518 		}
519 	}
520 	return (chars);
521 }
522 
523 /* convert double to ASCII */
524 static char *
525 __format_grouped_double(double value, int *flags,
526 			int left_prec, int right_prec, int pad_char) {
527 
528 	char		*rslt;
529 	char		*avalue;
530 	int		avalue_size;
531 
532 	size_t		bufsize;
533 	char		*bufend;
534 
535 	int		padded;
536 
537 	struct lconv	*lc = localeconv();
538 	char		*grouping;
539 	char		decimal_point;
540 	char		thousands_sep;
541 
542 	int groups = 0;
543 
544 	grouping = lc->mon_grouping;
545 	decimal_point = *lc->mon_decimal_point;
546 	if (decimal_point == '\0')
547 		decimal_point = *lc->decimal_point;
548 	thousands_sep = *lc->mon_thousands_sep;
549 	if (thousands_sep == '\0')
550 		thousands_sep = *lc->thousands_sep;
551 
552 	/* fill left_prec with default value */
553 	if (left_prec == -1)
554 		left_prec = 0;
555 
556 	/* fill right_prec with default value */
557 	if (right_prec == -1) {
558                 if (*flags & USE_INTL_CURRENCY)
559                         right_prec = lc->int_frac_digits;
560                 else
561                         right_prec = lc->frac_digits;
562 
563 		if (right_prec == CHAR_MAX)	/* POSIX locale ? */
564 			right_prec = 2;
565 	}
566 
567 	if (*flags & NEED_GROUPING)
568 		left_prec += get_groups(left_prec, grouping);
569 
570 	/* convert to string */
571 	avalue_size = asprintf(&avalue, "%*.*f", left_prec + right_prec + 1,
572 	    right_prec, value);
573 	if (avalue_size < 0)
574 		return (NULL);
575 
576 	/* make sure that we've enough space for result string */
577 	bufsize = avalue_size * 2 + 1;
578 	rslt = calloc(1, bufsize);
579 	if (rslt == NULL) {
580 		free(avalue);
581 		return (NULL);
582 	}
583 	bufend = rslt + bufsize - 1;	/* reserve space for trailing '\0' */
584 
585 	/* skip spaces at beginning */
586 	padded = 0;
587 	while (avalue[padded] == ' ') {
588 		padded++;
589 		avalue_size--;
590 	}
591 
592 	if (right_prec > 0) {
593 		bufend -= right_prec;
594 		memcpy(bufend, avalue + avalue_size+padded-right_prec,
595 		    right_prec);
596 		*--bufend = decimal_point;
597 		avalue_size -= (right_prec + 1);
598 	}
599 
600 	if ((*flags & NEED_GROUPING) &&
601 	    thousands_sep != '\0' &&	/* XXX: need investigation */
602 	    *grouping != CHAR_MAX &&
603 	    *grouping > 0) {
604 		while (avalue_size > (int)*grouping) {
605 			GRPCPY(*grouping);
606 			GRPSEP;
607 			grouping++;
608 
609 			/* no more grouping ? */
610 			if (*grouping == CHAR_MAX)
611 				break;
612 
613 			/* rest grouping with same value ? */
614 			if (*grouping == 0) {
615 				grouping--;
616 				while (avalue_size > *grouping) {
617 					GRPCPY(*grouping);
618 					GRPSEP;
619 				}
620 			}
621 		}
622 		if (avalue_size != 0)
623 			GRPCPY(avalue_size);
624 		padded -= groups;
625 
626 	} else {
627 		bufend -= avalue_size;
628 		memcpy(bufend, avalue+padded, avalue_size);
629 		if (right_prec == 0)
630 			padded--;	/* decrease assumed $decimal_point */
631 	}
632 
633 	/* do padding with pad_char */
634 	if (padded > 0) {
635 		bufend -= padded;
636 		memset(bufend, pad_char, padded);
637 	}
638 
639 	bufsize = bufsize - (bufend - rslt) + 1;
640 	memmove(rslt, bufend, bufsize);
641 	free(avalue);
642 	return (rslt);
643 }
644