xref: /netbsd-src/lib/libc/stdlib/strfmon.c (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06) 
1 /*	$NetBSD: strfmon.c,v 1.3 2005/12/02 14:19:43 yamt Exp $	*/
2 
3 /*-
4  * Copyright (c) 2001 Alexey Zelkin <phantom@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  */
29 
30 #include <sys/cdefs.h>
31 #if defined(LIBC_SCCS) && !defined(lint)
32 #if 0
33 __FBSDID("$FreeBSD: src/lib/libc/stdlib/strfmon.c,v 1.14 2003/03/20 08:18:55 ache Exp $");
34 #else
35 __RCSID("$NetBSD: strfmon.c,v 1.3 2005/12/02 14:19:43 yamt Exp $");
36 #endif
37 #endif /* LIBC_SCCS and not lint */
38 
39 #if defined(__NetBSD__)
40 #include "namespace.h"
41 #include <monetary.h>
42 #endif
43 
44 #include <sys/types.h>
45 #include <ctype.h>
46 #include <errno.h>
47 #include <limits.h>
48 #include <locale.h>
49 #include <stdarg.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 
54 /* internal flags */
55 #define	NEED_GROUPING		0x01	/* print digits grouped (default) */
56 #define	SIGN_POSN_USED		0x02	/* '+' or '(' usage flag */
57 #define	LOCALE_POSN		0x04	/* use locale defined +/- (default) */
58 #define	PARENTH_POSN		0x08	/* enclose negative amount in () */
59 #define	SUPRESS_CURR_SYMBOL	0x10	/* supress the currency from output */
60 #define	LEFT_JUSTIFY		0x20	/* left justify */
61 #define	USE_INTL_CURRENCY	0x40	/* use international currency symbol */
62 #define IS_NEGATIVE		0x80	/* is argument value negative ? */
63 
64 /* internal macros */
65 #define PRINT(CH) do {						\
66 	if (dst >= s + maxsize) 				\
67 		goto e2big_error;				\
68 	*dst++ = CH;						\
69 } while (/* CONSTCOND */ 0)
70 
71 #define PRINTS(STR) do {					\
72 	const char *tmps = STR;					\
73 	while (*tmps != '\0')					\
74 		PRINT(*tmps++);					\
75 } while (/* CONSTCOND */ 0)
76 
77 #define GET_NUMBER(VAR)	do {					\
78 	VAR = 0;						\
79 	while (isdigit((unsigned char)*fmt)) {			\
80 		VAR *= 10;					\
81 		VAR += *fmt - '0';				\
82 		fmt++;						\
83 	}							\
84 } while (/* CONSTCOND */ 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 (/* CONSTCOND */ 0)
93 
94 #define GRPSEP do {						\
95 	*--bufend = thousands_sep;				\
96 	groups++;						\
97 } while (/* CONSTCOND */ 0)
98 
99 static void __setup_vars(int, char *, char *, char *, const char **);
100 static int __calc_left_pad(int, char *);
101 static char *__format_grouped_double(double, int *, int, int, int);
102 
103 ssize_t
104 strfmon(char * __restrict s, size_t maxsize, const char * __restrict format,
105     ...)
106 {
107 	va_list		ap;
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 			*currency_symbol;
126 	const char	*signstr;
127 
128 	char		*tmpptr;	/* temporary vars */
129 	int		sverrno;
130 
131         va_start(ap, format);
132 
133 	lc = localeconv();
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 (/* CONSTCOND */ 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 (dst + width >= s + maxsize)
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 		}
212 
213 		/* Right precision */
214 		if (*fmt == '.') {
215 			if (!isdigit((unsigned char)*++fmt))
216 				goto format_error;
217 			GET_NUMBER(right_prec);
218 		}
219 
220 		/* Conversion Characters */
221 		switch (*fmt++) {
222 			case 'i':	/* use internaltion currency format */
223 				flags |= USE_INTL_CURRENCY;
224 				break;
225 			case 'n':	/* use national currency format */
226 				flags &= ~(USE_INTL_CURRENCY);
227 				break;
228 			default:	/* required character is missing or
229 					   premature EOS */
230 				goto format_error;
231 		}
232 
233 		if (flags & USE_INTL_CURRENCY) {
234 			currency_symbol = strdup(lc->int_curr_symbol);
235 			if (currency_symbol != NULL)
236 				space_char = *(currency_symbol+3);
237 		} else
238 			currency_symbol = strdup(lc->currency_symbol);
239 
240 		if (currency_symbol == NULL)
241 			goto end_error;			/* ENOMEM. */
242 
243 		/* value itself */
244 		value = va_arg(ap, double);
245 
246 		/* detect sign */
247 		if (value < 0) {
248 			flags |= IS_NEGATIVE;
249 			value = -value;
250 		}
251 
252 		/* fill left_prec with amount of padding chars */
253 		if (left_prec >= 0) {
254 			pad_size = __calc_left_pad((flags ^ IS_NEGATIVE),
255 							currency_symbol) -
256 				   __calc_left_pad(flags, currency_symbol);
257 			if (pad_size < 0)
258 				pad_size = 0;
259 		}
260 
261 		asciivalue = __format_grouped_double(value, &flags,
262 				left_prec, right_prec, pad_char);
263 		if (asciivalue == NULL)
264 			goto end_error;		/* errno already set     */
265 						/* to ENOMEM by malloc() */
266 
267 		/* set some variables for later use */
268 		__setup_vars(flags, &cs_precedes, &sep_by_space,
269 				&sign_posn, &signstr);
270 
271 		/*
272 		 * Description of some LC_MONETARY's values:
273 		 *
274 		 * p_cs_precedes & n_cs_precedes
275 		 *
276 		 * = 1 - $currency_symbol precedes the value
277 		 *       for a monetary quantity with a non-negative value
278 		 * = 0 - symbol succeeds the value
279 		 *
280 		 * p_sep_by_space & n_sep_by_space
281                  *
282 		 * = 0 - no space separates $currency_symbol
283 		 *       from the value for a monetary quantity with a
284 		 *	 non-negative value
285 		 * = 1 - space separates the symbol from the value
286 		 * = 2 - space separates the symbol and the sign string,
287 		 *       if adjacent.
288                  *
289 		 * p_sign_posn & n_sign_posn
290                  *
291 		 * = 0 - parentheses enclose the quantity and the
292 		 *	 $currency_symbol
293 		 * = 1 - the sign string precedes the quantity and the
294 		 *       $currency_symbol
295 		 * = 2 - the sign string succeeds the quantity and the
296 		 *       $currency_symbol
297 		 * = 3 - the sign string precedes the $currency_symbol
298 		 * = 4 - the sign string succeeds the $currency_symbol
299                  *
300 		 */
301 
302 		tmpptr = dst;
303 
304 		while (pad_size-- > 0)
305 			PRINT(' ');
306 
307 		if (sign_posn == 0 && (flags & IS_NEGATIVE))
308 			PRINT('(');
309 
310 		if (cs_precedes == 1) {
311 			if (sign_posn == 1 || sign_posn == 3) {
312 				PRINTS(signstr);
313 				if (sep_by_space == 2)		/* XXX: ? */
314 					PRINT(' ');
315 			}
316 
317 			if (!(flags & SUPRESS_CURR_SYMBOL)) {
318 				PRINTS(currency_symbol);
319 
320 				if (sign_posn == 4) {
321 					if (sep_by_space == 2)
322 						PRINT(space_char);
323 					PRINTS(signstr);
324 					if (sep_by_space == 1)
325 						PRINT(' ');
326 				} else if (sep_by_space == 1)
327 					PRINT(space_char);
328 			}
329 		} else if (sign_posn == 1)
330 			PRINTS(signstr);
331 
332 		PRINTS(asciivalue);
333 
334 		if (cs_precedes == 0) {
335 			if (sign_posn == 3) {
336 				if (sep_by_space == 1)
337 					PRINT(' ');
338 				PRINTS(signstr);
339 			}
340 
341 			if (!(flags & SUPRESS_CURR_SYMBOL)) {
342 				if ((sign_posn == 3 && sep_by_space == 2)
343 				    || (sep_by_space == 1
344 				    && (sign_posn == 0
345 				    || sign_posn == 1
346 				    || sign_posn == 2
347 				    || sign_posn == 4)))
348 					PRINT(space_char);
349 				PRINTS(currency_symbol); /* XXX: len */
350 				if (sign_posn == 4) {
351 					if (sep_by_space == 2)
352 						PRINT(' ');
353 					PRINTS(signstr);
354 				}
355 			}
356 		}
357 
358 		if (sign_posn == 2) {
359 			if (sep_by_space == 2)
360 				PRINT(' ');
361 			PRINTS(signstr);
362 		}
363 
364 		if (sign_posn == 0 && (flags & IS_NEGATIVE))
365 			PRINT(')');
366 
367 		if (dst - tmpptr < width) {
368 			if (flags & LEFT_JUSTIFY) {
369 				while (dst - tmpptr < width)
370 					PRINT(' ');
371 			} else {
372 				pad_size = dst-tmpptr;
373 				memmove(tmpptr + width-pad_size, tmpptr,
374 				    (size_t) pad_size);
375 				memset(tmpptr, ' ', (size_t) width-pad_size);
376 				dst += width-pad_size;
377 			}
378 		}
379 	}
380 
381 	PRINT('\0');
382 	va_end(ap);
383 	free(asciivalue);
384 	free(currency_symbol);
385 	return (dst - s - 1);	/* return size of put data except trailing '\0' */
386 
387 e2big_error:
388 	errno = E2BIG;
389 	goto end_error;
390 
391 format_error:
392 	errno = EINVAL;
393 
394 end_error:
395 	sverrno = errno;
396 	if (asciivalue != NULL)
397 		free(asciivalue);
398 	if (currency_symbol != NULL)
399 		free(currency_symbol);
400 	errno = sverrno;
401 	va_end(ap);
402 	return (-1);
403 }
404 
405 static void
406 __setup_vars(int flags, char *cs_precedes, char *sep_by_space,
407 		char *sign_posn, const char **signstr) {
408 	struct lconv *lc = localeconv();
409 
410 	if ((flags & IS_NEGATIVE) && (flags & USE_INTL_CURRENCY)) {
411 		*cs_precedes = lc->int_n_cs_precedes;
412 		*sep_by_space = lc->int_n_sep_by_space;
413 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_n_sign_posn;
414 		*signstr = (lc->negative_sign == '\0') ? "-"
415 		    : lc->negative_sign;
416 	} else if (flags & USE_INTL_CURRENCY) {
417 		*cs_precedes = lc->int_p_cs_precedes;
418 		*sep_by_space = lc->int_p_sep_by_space;
419 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_p_sign_posn;
420 		*signstr = lc->positive_sign;
421 	} else if (flags & IS_NEGATIVE) {
422 		*cs_precedes = lc->n_cs_precedes;
423 		*sep_by_space = lc->n_sep_by_space;
424 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->n_sign_posn;
425 		*signstr = (lc->negative_sign == '\0') ? "-"
426 		    : lc->negative_sign;
427 	} else {
428 		*cs_precedes = lc->p_cs_precedes;
429 		*sep_by_space = lc->p_sep_by_space;
430 		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->p_sign_posn;
431 		*signstr = lc->positive_sign;
432 	}
433 
434 	/* Set defult values for unspecified information. */
435 	if (*cs_precedes != 0)
436 		*cs_precedes = 1;
437 	if (*sep_by_space == CHAR_MAX)
438 		*sep_by_space = 0;
439 	if (*sign_posn == CHAR_MAX)
440 		*sign_posn = 0;
441 }
442 
443 static int
444 __calc_left_pad(int flags, char *cur_symb) {
445 
446 	char cs_precedes, sep_by_space, sign_posn;
447 	const char *signstr;
448 	int left_chars = 0;
449 
450 	__setup_vars(flags, &cs_precedes, &sep_by_space, &sign_posn, &signstr);
451 
452 	if (cs_precedes != 0) {
453 		left_chars += strlen(cur_symb);
454 		if (sep_by_space != 0)
455 			left_chars++;
456 	}
457 
458 	switch (sign_posn) {
459 		case 1:
460 			left_chars += strlen(signstr);
461 			break;
462 		case 3:
463 		case 4:
464 			if (cs_precedes != 0)
465 				left_chars += strlen(signstr);
466 	}
467 	return (left_chars);
468 }
469 
470 static int
471 get_groups(int size, char *grouping) {
472 
473 	int	chars = 0;
474 
475 	if (*grouping == CHAR_MAX || *grouping <= 0)	/* no grouping ? */
476 		return (0);
477 
478 	while (size > (int)*grouping) {
479 		chars++;
480 		size -= (int)*grouping++;
481 		/* no more grouping ? */
482 		if (*grouping == CHAR_MAX)
483 			break;
484 		/* rest grouping with same value ? */
485 		if (*grouping == 0) {
486 			chars += (size - 1) / *(grouping - 1);
487 			break;
488 		}
489 	}
490 	return (chars);
491 }
492 
493 /* convert double to ASCII */
494 static char *
495 __format_grouped_double(double value, int *flags,
496 			int left_prec, int right_prec, int pad_char) {
497 
498 	char		*rslt;
499 	char		*avalue;
500 	int		avalue_size;
501 	char		fmt[32];
502 
503 	size_t		bufsize;
504 	char		*bufend;
505 
506 	int		padded;
507 
508 	struct lconv	*lc = localeconv();
509 	char		*grouping;
510 	char		decimal_point;
511 	char		thousands_sep;
512 
513 	int groups = 0;
514 
515 	grouping = lc->mon_grouping;
516 	decimal_point = *lc->mon_decimal_point;
517 	if (decimal_point == '\0')
518 		decimal_point = *lc->decimal_point;
519 	thousands_sep = *lc->mon_thousands_sep;
520 	if (thousands_sep == '\0')
521 		thousands_sep = *lc->thousands_sep;
522 
523 	/* fill left_prec with default value */
524 	if (left_prec == -1)
525 		left_prec = 0;
526 
527 	/* fill right_prec with default value */
528 	if (right_prec == -1) {
529                 if (*flags & USE_INTL_CURRENCY)
530                         right_prec = lc->int_frac_digits;
531                 else
532                         right_prec = lc->frac_digits;
533 
534 		if (right_prec == CHAR_MAX)	/* POSIX locale ? */
535 			right_prec = 2;
536 	}
537 
538 	if (*flags & NEED_GROUPING)
539 		left_prec += get_groups(left_prec, grouping);
540 
541 	/* convert to string */
542 	snprintf(fmt, sizeof(fmt), "%%%d.%df", left_prec + right_prec + 1,
543 	    right_prec);
544 	avalue_size = asprintf(&avalue, fmt, value);
545 	if (avalue_size < 0)
546 		return (NULL);
547 
548 	/* make sure that we've enough space for result string */
549 	bufsize = strlen(avalue)*2+1;
550 	rslt = malloc(bufsize);
551 	if (rslt == NULL) {
552 		free(avalue);
553 		return (NULL);
554 	}
555 	memset(rslt, 0, bufsize);
556 	bufend = rslt + bufsize - 1;	/* reserve space for trailing '\0' */
557 
558 	/* skip spaces at beggining */
559 	padded = 0;
560 	while (avalue[padded] == ' ') {
561 		padded++;
562 		avalue_size--;
563 	}
564 
565 	if (right_prec > 0) {
566 		bufend -= right_prec;
567 		memcpy(bufend, avalue + avalue_size+padded-right_prec,
568 		    (size_t) right_prec);
569 		*--bufend = decimal_point;
570 		avalue_size -= (right_prec + 1);
571 	}
572 
573 	if ((*flags & NEED_GROUPING) &&
574 	    thousands_sep != '\0' &&	/* XXX: need investigation */
575 	    *grouping != CHAR_MAX &&
576 	    *grouping > 0) {
577 		while (avalue_size > (int)*grouping) {
578 			GRPCPY(*grouping);
579 			GRPSEP;
580 			grouping++;
581 
582 			/* no more grouping ? */
583 			if (*grouping == CHAR_MAX)
584 				break;
585 
586 			/* rest grouping with same value ? */
587 			if (*grouping == 0) {
588 				grouping--;
589 				while (avalue_size > *grouping) {
590 					GRPCPY(*grouping);
591 					GRPSEP;
592 				}
593 			}
594 		}
595 		if (avalue_size != 0)
596 			GRPCPY(avalue_size);
597 		padded -= groups;
598 
599 	} else {
600 		bufend -= avalue_size;
601 		memcpy(bufend, avalue+padded, (size_t) avalue_size);
602 		if (right_prec == 0)
603 			padded--;	/* decrease assumed $decimal_point */
604 	}
605 
606 	/* do padding with pad_char */
607 	if (padded > 0) {
608 		bufend -= padded;
609 		memset(bufend, pad_char, (size_t) padded);
610 	}
611 
612 	bufsize = bufsize - (bufend - rslt) + 1;
613 	memmove(rslt, bufend, bufsize);
614 	free(avalue);
615 	return (rslt);
616 }
617