strfmon.c revision 178457 
1/*-
2 * Copyright (c) 2001 Alexey Zelkin <phantom@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD: head/lib/libc/stdlib/strfmon.c 178457 2008-04-24 07:49:00Z ru $");
30
31#include <sys/types.h>
32#include <ctype.h>
33#include <errno.h>
34#include <limits.h>
35#include <locale.h>
36#include <monetary.h>
37#include <stdarg.h>
38#include <stdio.h>
39#include <stdlib.h>
40#include <string.h>
41
42/* internal flags */
43#define	NEED_GROUPING		0x01	/* print digits grouped (default) */
44#define	SIGN_POSN_USED		0x02	/* '+' or '(' usage flag */
45#define	LOCALE_POSN		0x04	/* use locale defined +/- (default) */
46#define	PARENTH_POSN		0x08	/* enclose negative amount in () */
47#define	SUPRESS_CURR_SYMBOL	0x10	/* supress the currency from output */
48#define	LEFT_JUSTIFY		0x20	/* left justify */
49#define	USE_INTL_CURRENCY	0x40	/* use international currency symbol */
50#define IS_NEGATIVE		0x80	/* is argument value negative ? */
51
52/* internal macros */
53#define PRINT(CH) do {						\
54	if (dst >= s + maxsize) 				\
55		goto e2big_error;				\
56	*dst++ = CH;						\
57} while (0)
58
59#define PRINTS(STR) do {					\
60	char *tmps = STR;					\
61	while (*tmps != '\0')					\
62		PRINT(*tmps++);					\
63} while (0)
64
65#define GET_NUMBER(VAR)	do {					\
66	VAR = 0;						\
67	while (isdigit((unsigned char)*fmt)) {			\
68		if (VAR > INT_MAX / 10)				\
69			goto e2big_error;			\
70		VAR *= 10;					\
71		VAR += *fmt - '0';				\
72		if (VAR < 0)					\
73			goto e2big_error;			\
74		fmt++;						\
75	}							\
76} while (0)
77
78#define GRPCPY(howmany) do {					\
79	int i = howmany;					\
80	while (i-- > 0) {					\
81		avalue_size--;					\
82		*--bufend = *(avalue+avalue_size+padded);	\
83	}							\
84} while (0)
85
86#define GRPSEP do {						\
87	*--bufend = thousands_sep;				\
88	groups++;						\
89} while (0)
90
91static void __setup_vars(int, char *, char *, char *, char **);
92static int __calc_left_pad(int, char *);
93static char *__format_grouped_double(double, int *, int, int, int);
94
95ssize_t
96strfmon(char * __restrict s, size_t maxsize, const char * __restrict format,
97    ...)
98{
99	va_list		ap;
100	char 		*dst;		/* output destination pointer */
101	const char 	*fmt;		/* current format poistion pointer */
102	struct lconv 	*lc;		/* pointer to lconv structure */
103	char		*asciivalue;	/* formatted double pointer */
104
105	int		flags;		/* formatting options */
106	int		pad_char;	/* padding character */
107	int		pad_size;	/* pad size */
108	int		width;		/* field width */
109	int		left_prec;	/* left precision */
110	int		right_prec;	/* right precision */
111	double		value;		/* just value */
112	char		space_char = ' '; /* space after currency */
113
114	char		cs_precedes,	/* values gathered from struct lconv */
115			sep_by_space,
116			sign_posn,
117			*signstr,
118			*currency_symbol;
119
120	char		*tmpptr;	/* temporary vars */
121	int		sverrno;
122
123        va_start(ap, format);
124
125	lc = localeconv();
126	dst = s;
127	fmt = format;
128	asciivalue = NULL;
129	currency_symbol = NULL;
130	pad_size = 0;
131
132	while (*fmt) {
133		/* pass nonformating characters AS IS */
134		if (*fmt != '%')
135			goto literal;
136
137		/* '%' found ! */
138
139		/* "%%" mean just '%' */
140		if (*(fmt+1) == '%') {
141			fmt++;
142	literal:
143			PRINT(*fmt++);
144			continue;
145		}
146
147		/* set up initial values */
148		flags = (NEED_GROUPING|LOCALE_POSN);
149		pad_char = ' ';		/* padding character is "space" */
150		left_prec = -1;		/* no left precision specified */
151		right_prec = -1;	/* no right precision specified */
152		width = -1;		/* no width specified */
153		value = 0;		/* we have no value to print now */
154
155		/* Flags */
156		while (1) {
157			switch (*++fmt) {
158				case '=':	/* fill character */
159					pad_char = *++fmt;
160					if (pad_char == '\0')
161						goto format_error;
162					continue;
163				case '^':	/* not group currency  */
164					flags &= ~(NEED_GROUPING);
165					continue;
166				case '+':	/* use locale defined signs */
167					if (flags & SIGN_POSN_USED)
168						goto format_error;
169					flags |= (SIGN_POSN_USED|LOCALE_POSN);
170					continue;
171				case '(':	/* enclose negatives with () */
172					if (flags & SIGN_POSN_USED)
173						goto format_error;
174					flags |= (SIGN_POSN_USED|PARENTH_POSN);
175					continue;
176				case '!':	/* suppress currency symbol */
177					flags |= SUPRESS_CURR_SYMBOL;
178					continue;
179				case '-':	/* alignment (left)  */
180					flags |= LEFT_JUSTIFY;
181					continue;
182				default:
183					break;
184			}
185			break;
186		}
187
188		/* field Width */
189		if (isdigit((unsigned char)*fmt)) {
190			GET_NUMBER(width);
191			/* Do we have enough space to put number with
192			 * required width ?
193			 */
194			if ((unsigned int)width >= maxsize - (dst - s))
195				goto e2big_error;
196		}
197
198		/* Left precision */
199		if (*fmt == '#') {
200			if (!isdigit((unsigned char)*++fmt))
201				goto format_error;
202			GET_NUMBER(left_prec);
203			if ((unsigned int)left_prec >= maxsize - (dst - s))
204				goto e2big_error;
205		}
206
207		/* Right precision */
208		if (*fmt == '.') {
209			if (!isdigit((unsigned char)*++fmt))
210				goto format_error;
211			GET_NUMBER(right_prec);
212			if ((unsigned int)right_prec >= maxsize - (dst - s) -
213			    left_prec)
214				goto e2big_error;
215		}
216
217		/* Conversion Characters */
218		switch (*fmt++) {
219			case 'i':	/* use internaltion currency format */
220				flags |= USE_INTL_CURRENCY;
221				break;
222			case 'n':	/* use national currency format */
223				flags &= ~(USE_INTL_CURRENCY);
224				break;
225			default:	/* required character is missing or
226					   premature EOS */
227				goto format_error;
228		}
229
230		if (currency_symbol != NULL)
231			free(currency_symbol);
232		if (flags & USE_INTL_CURRENCY) {
233			currency_symbol = strdup(lc->int_curr_symbol);
234			if (currency_symbol != NULL)
235				space_char = *(currency_symbol+3);
236		} else
237			currency_symbol = strdup(lc->currency_symbol);
238
239		if (currency_symbol == NULL)
240			goto end_error;			/* ENOMEM. */
241
242		/* value itself */
243		value = va_arg(ap, double);
244
245		/* detect sign */
246		if (value < 0) {
247			flags |= IS_NEGATIVE;
248			value = -value;
249		}
250
251		/* fill left_prec with amount of padding chars */
252		if (left_prec >= 0) {
253			pad_size = __calc_left_pad((flags ^ IS_NEGATIVE),
254							currency_symbol) -
255				   __calc_left_pad(flags, currency_symbol);
256			if (pad_size < 0)
257				pad_size = 0;
258		}
259
260		if (asciivalue != NULL)
261			free(asciivalue);
262		asciivalue = __format_grouped_double(value, &flags,
263				left_prec, right_prec, pad_char);
264		if (asciivalue == NULL)
265			goto end_error;		/* errno already set     */
266						/* to ENOMEM by malloc() */
267
268		/* set some variables for later use */
269		__setup_vars(flags, &cs_precedes, &sep_by_space,
270				&sign_posn, &signstr);
271
272		/*
273		 * Description of some LC_MONETARY's values:
274		 *
275		 * p_cs_precedes & n_cs_precedes
276		 *
277		 * = 1 - $currency_symbol precedes the value
278		 *       for a monetary quantity with a non-negative value
279		 * = 0 - symbol succeeds the value
280		 *
281		 * p_sep_by_space & n_sep_by_space
282                 *
283		 * = 0 - no space separates $currency_symbol
284		 *       from the value for a monetary quantity with a
285		 *	 non-negative value
286		 * = 1 - space separates the symbol from the value
287		 * = 2 - space separates the symbol and the sign string,
288		 *       if adjacent.
289                 *
290		 * p_sign_posn & n_sign_posn
291                 *
292		 * = 0 - parentheses enclose the quantity and the
293		 *	 $currency_symbol
294		 * = 1 - the sign string precedes the quantity and the
295		 *       $currency_symbol
296		 * = 2 - the sign string succeeds the quantity and the
297		 *       $currency_symbol
298		 * = 3 - the sign string precedes the $currency_symbol
299		 * = 4 - the sign string succeeds the $currency_symbol
300                 *
301		 */
302
303		tmpptr = dst;
304
305		while (pad_size-- > 0)
306			PRINT(' ');
307
308		if (sign_posn == 0 && (flags & IS_NEGATIVE))
309			PRINT('(');
310
311		if (cs_precedes == 1) {
312			if (sign_posn == 1 || sign_posn == 3) {
313				PRINTS(signstr);
314				if (sep_by_space == 2)		/* XXX: ? */
315					PRINT(' ');
316			}
317
318			if (!(flags & SUPRESS_CURR_SYMBOL)) {
319				PRINTS(currency_symbol);
320
321				if (sign_posn == 4) {
322					if (sep_by_space == 2)
323						PRINT(space_char);
324					PRINTS(signstr);
325					if (sep_by_space == 1)
326						PRINT(' ');
327				} else if (sep_by_space == 1)
328					PRINT(space_char);
329			}
330		} else if (sign_posn == 1)
331			PRINTS(signstr);
332
333		PRINTS(asciivalue);
334
335		if (cs_precedes == 0) {
336			if (sign_posn == 3) {
337				if (sep_by_space == 1)
338					PRINT(' ');
339				PRINTS(signstr);
340			}
341
342			if (!(flags & SUPRESS_CURR_SYMBOL)) {
343				if ((sign_posn == 3 && sep_by_space == 2)
344				    || (sep_by_space == 1
345				    && (sign_posn == 0
346				    || sign_posn == 1
347				    || sign_posn == 2
348				    || sign_posn == 4)))
349					PRINT(space_char);
350				PRINTS(currency_symbol); /* XXX: len */
351				if (sign_posn == 4) {
352					if (sep_by_space == 2)
353						PRINT(' ');
354					PRINTS(signstr);
355				}
356			}
357		}
358
359		if (sign_posn == 2) {
360			if (sep_by_space == 2)
361				PRINT(' ');
362			PRINTS(signstr);
363		}
364
365		if (sign_posn == 0 && (flags & IS_NEGATIVE))
366			PRINT(')');
367
368		if (dst - tmpptr < width) {
369			if (flags & LEFT_JUSTIFY) {
370				while (dst - tmpptr < width)
371					PRINT(' ');
372			} else {
373				pad_size = dst-tmpptr;
374				memmove(tmpptr + width-pad_size, tmpptr,
375				    pad_size);
376				memset(tmpptr, ' ', width-pad_size);
377				dst += width-pad_size;
378			}
379		}
380	}
381
382	PRINT('\0');
383	va_end(ap);
384	free(asciivalue);
385	free(currency_symbol);
386	return (dst - s - 1);	/* return size of put data except trailing '\0' */
387
388e2big_error:
389	errno = E2BIG;
390	goto end_error;
391
392format_error:
393	errno = EINVAL;
394
395end_error:
396	sverrno = errno;
397	if (asciivalue != NULL)
398		free(asciivalue);
399	if (currency_symbol != NULL)
400		free(currency_symbol);
401	errno = sverrno;
402	va_end(ap);
403	return (-1);
404}
405
406static void
407__setup_vars(int flags, char *cs_precedes, char *sep_by_space,
408		char *sign_posn, char **signstr) {
409
410	struct lconv *lc = localeconv();
411
412	if ((flags & IS_NEGATIVE) && (flags & USE_INTL_CURRENCY)) {
413		*cs_precedes = lc->int_n_cs_precedes;
414		*sep_by_space = lc->int_n_sep_by_space;
415		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_n_sign_posn;
416		*signstr = (lc->negative_sign == '\0') ? "-"
417		    : lc->negative_sign;
418	} else if (flags & USE_INTL_CURRENCY) {
419		*cs_precedes = lc->int_p_cs_precedes;
420		*sep_by_space = lc->int_p_sep_by_space;
421		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_p_sign_posn;
422		*signstr = lc->positive_sign;
423	} else if (flags & IS_NEGATIVE) {
424		*cs_precedes = lc->n_cs_precedes;
425		*sep_by_space = lc->n_sep_by_space;
426		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->n_sign_posn;
427		*signstr = (lc->negative_sign == '\0') ? "-"
428		    : lc->negative_sign;
429	} else {
430		*cs_precedes = lc->p_cs_precedes;
431		*sep_by_space = lc->p_sep_by_space;
432		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->p_sign_posn;
433		*signstr = lc->positive_sign;
434	}
435
436	/* Set defult values for unspecified information. */
437	if (*cs_precedes != 0)
438		*cs_precedes = 1;
439	if (*sep_by_space == CHAR_MAX)
440		*sep_by_space = 0;
441	if (*sign_posn == CHAR_MAX)
442		*sign_posn = 0;
443}
444
445static int
446__calc_left_pad(int flags, char *cur_symb) {
447
448	char cs_precedes, sep_by_space, sign_posn, *signstr;
449	int left_chars = 0;
450
451	__setup_vars(flags, &cs_precedes, &sep_by_space, &sign_posn, &signstr);
452
453	if (cs_precedes != 0) {
454		left_chars += strlen(cur_symb);
455		if (sep_by_space != 0)
456			left_chars++;
457	}
458
459	switch (sign_posn) {
460		case 1:
461			left_chars += strlen(signstr);
462			break;
463		case 3:
464		case 4:
465			if (cs_precedes != 0)
466				left_chars += strlen(signstr);
467	}
468	return (left_chars);
469}
470
471static int
472get_groups(int size, char *grouping) {
473
474	int	chars = 0;
475
476	if (*grouping == CHAR_MAX || *grouping <= 0)	/* no grouping ? */
477		return (0);
478
479	while (size > (int)*grouping) {
480		chars++;
481		size -= (int)*grouping++;
482		/* no more grouping ? */
483		if (*grouping == CHAR_MAX)
484			break;
485		/* rest grouping with same value ? */
486		if (*grouping == 0) {
487			chars += (size - 1) / *(grouping - 1);
488			break;
489		}
490	}
491	return (chars);
492}
493
494/* convert double to ASCII */
495static char *
496__format_grouped_double(double value, int *flags,
497			int left_prec, int right_prec, int pad_char) {
498
499	char		*rslt;
500	char		*avalue;
501	int		avalue_size;
502	char		fmt[32];
503
504	size_t		bufsize;
505	char		*bufend;
506
507	int		padded;
508
509	struct lconv	*lc = localeconv();
510	char		*grouping;
511	char		decimal_point;
512	char		thousands_sep;
513
514	int groups = 0;
515
516	grouping = lc->mon_grouping;
517	decimal_point = *lc->mon_decimal_point;
518	if (decimal_point == '\0')
519		decimal_point = *lc->decimal_point;
520	thousands_sep = *lc->mon_thousands_sep;
521	if (thousands_sep == '\0')
522		thousands_sep = *lc->thousands_sep;
523
524	/* fill left_prec with default value */
525	if (left_prec == -1)
526		left_prec = 0;
527
528	/* fill right_prec with default value */
529	if (right_prec == -1) {
530                if (*flags & USE_INTL_CURRENCY)
531                        right_prec = lc->int_frac_digits;
532                else
533                        right_prec = lc->frac_digits;
534
535		if (right_prec == CHAR_MAX)	/* POSIX locale ? */
536			right_prec = 2;
537	}
538
539	if (*flags & NEED_GROUPING)
540		left_prec += get_groups(left_prec, grouping);
541
542	/* convert to string */
543	snprintf(fmt, sizeof(fmt), "%%%d.%df", left_prec + right_prec + 1,
544	    right_prec);
545	avalue_size = asprintf(&avalue, fmt, value);
546	if (avalue_size < 0)
547		return (NULL);
548
549	/* make sure that we've enough space for result string */
550	bufsize = strlen(avalue)*2+1;
551	rslt = calloc(1, bufsize);
552	if (rslt == NULL) {
553		free(avalue);
554		return (NULL);
555	}
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		    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, 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, padded);
610	}
611
612	bufsize = bufsize - (bufend - rslt) + 1;
613	memmove(rslt, bufend, bufsize);
614	free(avalue);
615	return (rslt);
616}
617