xref: /freebsd/usr.bin/printf/printf.c (revision 0572ccaa4543b0abef8ef81e384c1d04de9f3da1)
1 /*-
2  * Copyright 2014 Garrett D'Amore <garrett@damore.org>
3  * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  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  * 4. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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  * Important: This file is used both as a standalone program /usr/bin/printf
33  * and as a builtin for /bin/sh (#define SHELL).
34  */
35 
36 #ifndef SHELL
37 #ifndef lint
38 static char const copyright[] =
39 "@(#) Copyright (c) 1989, 1993\n\
40 	The Regents of the University of California.  All rights reserved.\n";
41 #endif /* not lint */
42 #endif
43 
44 #ifndef lint
45 #if 0
46 static char const sccsid[] = "@(#)printf.c	8.1 (Berkeley) 7/20/93";
47 #endif
48 static const char rcsid[] =
49   "$FreeBSD$";
50 #endif /* not lint */
51 
52 #include <sys/types.h>
53 
54 #include <ctype.h>
55 #include <err.h>
56 #include <errno.h>
57 #include <inttypes.h>
58 #include <limits.h>
59 #include <locale.h>
60 #include <stdio.h>
61 #include <stdlib.h>
62 #include <string.h>
63 #include <unistd.h>
64 #include <wchar.h>
65 
66 #ifdef SHELL
67 #define	main printfcmd
68 #include "bltin/bltin.h"
69 #include "error.h"
70 #include "options.h"
71 #endif
72 
73 #define	PF(f, func) do {						\
74 	char *b = NULL;							\
75 	if (havewidth)							\
76 		if (haveprec)						\
77 			(void)asprintf(&b, f, fieldwidth, precision, func); \
78 		else							\
79 			(void)asprintf(&b, f, fieldwidth, func);	\
80 	else if (haveprec)						\
81 		(void)asprintf(&b, f, precision, func);			\
82 	else								\
83 		(void)asprintf(&b, f, func);				\
84 	if (b) {							\
85 		(void)fputs(b, stdout);					\
86 		free(b);						\
87 	}								\
88 } while (0)
89 
90 static int	 asciicode(void);
91 static char	*printf_doformat(char *, int *);
92 static int	 escape(char *, int, size_t *);
93 static int	 getchr(void);
94 static int	 getfloating(long double *, int);
95 static int	 getint(int *);
96 static int	 getnum(intmax_t *, uintmax_t *, int);
97 static const char
98 		*getstr(void);
99 static char	*mknum(char *, char);
100 static void	 usage(void);
101 
102 static const char digits[] = "0123456789";
103 
104 static char end_fmt[1];
105 
106 static int  myargc;
107 static char **myargv;
108 static char **gargv;
109 static char **maxargv;
110 
111 int
112 main(int argc, char *argv[])
113 {
114 	size_t len;
115 	int end, rval;
116 	char *format, *fmt, *start;
117 #ifndef SHELL
118 	int ch;
119 
120 	(void) setlocale(LC_ALL, "");
121 #endif
122 
123 #ifdef SHELL
124 	nextopt("");
125 	argc -= argptr - argv;
126 	argv = argptr;
127 #else
128 	while ((ch = getopt(argc, argv, "")) != -1)
129 		switch (ch) {
130 		case '?':
131 		default:
132 			usage();
133 			return (1);
134 		}
135 	argc -= optind;
136 	argv += optind;
137 #endif
138 
139 	if (argc < 1) {
140 		usage();
141 		return (1);
142 	}
143 
144 #ifdef SHELL
145 	INTOFF;
146 #endif
147 	/*
148 	 * Basic algorithm is to scan the format string for conversion
149 	 * specifications -- once one is found, find out if the field
150 	 * width or precision is a '*'; if it is, gather up value.  Note,
151 	 * format strings are reused as necessary to use up the provided
152 	 * arguments, arguments of zero/null string are provided to use
153 	 * up the format string.
154 	 */
155 	fmt = format = *argv;
156 	escape(fmt, 1, &len);		/* backslash interpretation */
157 	rval = end = 0;
158 	gargv = ++argv;
159 
160 	for (;;) {
161 		maxargv = gargv;
162 
163 		myargv = gargv;
164 		for (myargc = 0; gargv[myargc]; myargc++)
165 			/* nop */;
166 		start = fmt;
167 		while (fmt < format + len) {
168 			if (fmt[0] == '%') {
169 				fwrite(start, 1, fmt - start, stdout);
170 				if (fmt[1] == '%') {
171 					/* %% prints a % */
172 					putchar('%');
173 					fmt += 2;
174 				} else {
175 					fmt = printf_doformat(fmt, &rval);
176 					if (fmt == NULL || fmt == end_fmt) {
177 #ifdef SHELL
178 						INTON;
179 #endif
180 						return (fmt == NULL ? 1 : rval);
181 					}
182 					end = 0;
183 				}
184 				start = fmt;
185 			} else
186 				fmt++;
187 			if (gargv > maxargv)
188 				maxargv = gargv;
189 		}
190 		gargv = maxargv;
191 
192 		if (end == 1) {
193 			warnx("missing format character");
194 #ifdef SHELL
195 			INTON;
196 #endif
197 			return (1);
198 		}
199 		fwrite(start, 1, fmt - start, stdout);
200 		if (!*gargv) {
201 #ifdef SHELL
202 			INTON;
203 #endif
204 			return (rval);
205 		}
206 		/* Restart at the beginning of the format string. */
207 		fmt = format;
208 		end = 1;
209 	}
210 	/* NOTREACHED */
211 }
212 
213 
214 static char *
215 printf_doformat(char *fmt, int *rval)
216 {
217 	static const char skip1[] = "#'-+ 0";
218 	int fieldwidth, haveprec, havewidth, mod_ldbl, precision;
219 	char convch, nextch;
220 	char start[strlen(fmt) + 1];
221 	char **fargv;
222 	char *dptr;
223 	int l;
224 
225 	dptr = start;
226 	*dptr++ = '%';
227 	*dptr = 0;
228 
229 	fmt++;
230 
231 	/* look for "n$" field index specifier */
232 	l = strspn(fmt, digits);
233 	if ((l > 0) && (fmt[l] == '$')) {
234 		int idx = atoi(fmt);
235 		if (idx <= myargc) {
236 			gargv = &myargv[idx - 1];
237 		} else {
238 			gargv = &myargv[myargc];
239 		}
240 		if (gargv > maxargv)
241 			maxargv = gargv;
242 		fmt += l + 1;
243 
244 		/* save format argument */
245 		fargv = gargv;
246 	} else {
247 	fargv = NULL;
248 	}
249 
250 	/* skip to field width */
251 	while (strchr(skip1, *fmt) != NULL) {
252 		*dptr++ = *fmt++;
253 		*dptr = 0;
254 	}
255 
256 	if (*fmt == '*') {
257 
258 		fmt++;
259 		l = strspn(fmt, digits);
260 		if ((l > 0) && (fmt[l] == '$')) {
261 			int idx = atoi(fmt);
262 			if (idx <= myargc) {
263 				gargv = &myargv[idx - 1];
264 			} else {
265 				gargv = &myargv[myargc];
266 			}
267 			fmt += l + 1;
268 		}
269 
270 		if (getint(&fieldwidth))
271 			return (NULL);
272 		if (gargv > maxargv)
273 			maxargv = gargv;
274 		havewidth = 1;
275 
276 		*dptr++ = '*';
277 		*dptr = 0;
278 	} else {
279 		havewidth = 0;
280 
281 		/* skip to possible '.', get following precision */
282 		while (isdigit(*fmt)) {
283 			*dptr++ = *fmt++;
284 			*dptr = 0;
285 		}
286 	}
287 
288 	if (*fmt == '.') {
289 		/* precision present? */
290 		fmt++;
291 		*dptr++ = '.';
292 
293 		if (*fmt == '*') {
294 
295 			fmt++;
296 			l = strspn(fmt, digits);
297 			if ((l > 0) && (fmt[l] == '$')) {
298 				int idx = atoi(fmt);
299 				if (idx <= myargc) {
300 					gargv = &myargv[idx - 1];
301 				} else {
302 					gargv = &myargv[myargc];
303 				}
304 				fmt += l + 1;
305 			}
306 
307 			if (getint(&precision))
308 				return (NULL);
309 			if (gargv > maxargv)
310 				maxargv = gargv;
311 			haveprec = 1;
312 			*dptr++ = '*';
313 			*dptr = 0;
314 		} else {
315 			haveprec = 0;
316 
317 			/* skip to conversion char */
318 			while (isdigit(*fmt)) {
319 				*dptr++ = *fmt++;
320 				*dptr = 0;
321 			}
322 		}
323 	} else
324 		haveprec = 0;
325 	if (!*fmt) {
326 		warnx("missing format character");
327 		return (NULL);
328 	}
329 	*dptr++ = *fmt;
330 	*dptr = 0;
331 
332 	/*
333 	 * Look for a length modifier.  POSIX doesn't have these, so
334 	 * we only support them for floating-point conversions, which
335 	 * are extensions.  This is useful because the L modifier can
336 	 * be used to gain extra range and precision, while omitting
337 	 * it is more likely to produce consistent results on different
338 	 * architectures.  This is not so important for integers
339 	 * because overflow is the only bad thing that can happen to
340 	 * them, but consider the command  printf %a 1.1
341 	 */
342 	if (*fmt == 'L') {
343 		mod_ldbl = 1;
344 		fmt++;
345 		if (!strchr("aAeEfFgG", *fmt)) {
346 			warnx("bad modifier L for %%%c", *fmt);
347 			return (NULL);
348 		}
349 	} else {
350 		mod_ldbl = 0;
351 	}
352 
353 	/* save the current arg offset, and set to the format arg */
354 	if (fargv != NULL) {
355 		gargv = fargv;
356 	}
357 
358 	convch = *fmt;
359 	nextch = *++fmt;
360 
361 	*fmt = '\0';
362 	switch (convch) {
363 	case 'b': {
364 		size_t len;
365 		char *p;
366 		int getout;
367 
368 		p = strdup(getstr());
369 		if (p == NULL) {
370 			warnx("%s", strerror(ENOMEM));
371 			return (NULL);
372 		}
373 		getout = escape(p, 0, &len);
374 		fputs(p, stdout);
375 		free(p);
376 		if (getout)
377 			return (end_fmt);
378 		break;
379 	}
380 	case 'c': {
381 		char p;
382 
383 		p = getchr();
384 		PF(start, p);
385 		break;
386 	}
387 	case 's': {
388 		const char *p;
389 
390 		p = getstr();
391 		PF(start, p);
392 		break;
393 	}
394 	case 'd': case 'i': case 'o': case 'u': case 'x': case 'X': {
395 		char *f;
396 		intmax_t val;
397 		uintmax_t uval;
398 		int signedconv;
399 
400 		signedconv = (convch == 'd' || convch == 'i');
401 		if ((f = mknum(start, convch)) == NULL)
402 			return (NULL);
403 		if (getnum(&val, &uval, signedconv))
404 			*rval = 1;
405 		if (signedconv)
406 			PF(f, val);
407 		else
408 			PF(f, uval);
409 		break;
410 	}
411 	case 'e': case 'E':
412 	case 'f': case 'F':
413 	case 'g': case 'G':
414 	case 'a': case 'A': {
415 		long double p;
416 
417 		if (getfloating(&p, mod_ldbl))
418 			*rval = 1;
419 		if (mod_ldbl)
420 			PF(start, p);
421 		else
422 			PF(start, (double)p);
423 		break;
424 	}
425 	default:
426 		warnx("illegal format character %c", convch);
427 		return (NULL);
428 	}
429 	*fmt = nextch;
430 	/* return the gargv to the next element */
431 	return (fmt);
432 }
433 
434 static char *
435 mknum(char *str, char ch)
436 {
437 	static char *copy;
438 	static size_t copy_size;
439 	char *newcopy;
440 	size_t len, newlen;
441 
442 	len = strlen(str) + 2;
443 	if (len > copy_size) {
444 		newlen = ((len + 1023) >> 10) << 10;
445 		if ((newcopy = realloc(copy, newlen)) == NULL)
446 		{
447 			warnx("%s", strerror(ENOMEM));
448 			return (NULL);
449 		}
450 		copy = newcopy;
451 		copy_size = newlen;
452 	}
453 
454 	memmove(copy, str, len - 3);
455 	copy[len - 3] = 'j';
456 	copy[len - 2] = ch;
457 	copy[len - 1] = '\0';
458 	return (copy);
459 }
460 
461 static int
462 escape(char *fmt, int percent, size_t *len)
463 {
464 	char *save, *store, c;
465 	int value;
466 
467 	for (save = store = fmt; ((c = *fmt) != 0); ++fmt, ++store) {
468 		if (c != '\\') {
469 			*store = c;
470 			continue;
471 		}
472 		switch (*++fmt) {
473 		case '\0':		/* EOS, user error */
474 			*store = '\\';
475 			*++store = '\0';
476 			*len = store - save;
477 			return (0);
478 		case '\\':		/* backslash */
479 		case '\'':		/* single quote */
480 			*store = *fmt;
481 			break;
482 		case 'a':		/* bell/alert */
483 			*store = '\a';
484 			break;
485 		case 'b':		/* backspace */
486 			*store = '\b';
487 			break;
488 		case 'c':
489 			if (!percent) {
490 				*store = '\0';
491 				*len = store - save;
492 				return (1);
493 			}
494 			*store = 'c';
495 			break;
496 		case 'f':		/* form-feed */
497 			*store = '\f';
498 			break;
499 		case 'n':		/* newline */
500 			*store = '\n';
501 			break;
502 		case 'r':		/* carriage-return */
503 			*store = '\r';
504 			break;
505 		case 't':		/* horizontal tab */
506 			*store = '\t';
507 			break;
508 		case 'v':		/* vertical tab */
509 			*store = '\v';
510 			break;
511 					/* octal constant */
512 		case '0': case '1': case '2': case '3':
513 		case '4': case '5': case '6': case '7':
514 			c = (!percent && *fmt == '0') ? 4 : 3;
515 			for (value = 0;
516 			    c-- && *fmt >= '0' && *fmt <= '7'; ++fmt) {
517 				value <<= 3;
518 				value += *fmt - '0';
519 			}
520 			--fmt;
521 			if (percent && value == '%') {
522 				*store++ = '%';
523 				*store = '%';
524 			} else
525 				*store = (char)value;
526 			break;
527 		default:
528 			*store = *fmt;
529 			break;
530 		}
531 	}
532 	*store = '\0';
533 	*len = store - save;
534 	return (0);
535 }
536 
537 static int
538 getchr(void)
539 {
540 	if (!*gargv)
541 		return ('\0');
542 	return ((int)**gargv++);
543 }
544 
545 static const char *
546 getstr(void)
547 {
548 	if (!*gargv)
549 		return ("");
550 	return (*gargv++);
551 }
552 
553 static int
554 getint(int *ip)
555 {
556 	intmax_t val;
557 	uintmax_t uval;
558 	int rval;
559 
560 	if (getnum(&val, &uval, 1))
561 		return (1);
562 	rval = 0;
563 	if (val < INT_MIN || val > INT_MAX) {
564 		warnx("%s: %s", *gargv, strerror(ERANGE));
565 		rval = 1;
566 	}
567 	*ip = (int)val;
568 	return (rval);
569 }
570 
571 static int
572 getnum(intmax_t *ip, uintmax_t *uip, int signedconv)
573 {
574 	char *ep;
575 	int rval;
576 
577 	if (!*gargv) {
578 		*ip = *uip = 0;
579 		return (0);
580 	}
581 	if (**gargv == '"' || **gargv == '\'') {
582 		if (signedconv)
583 			*ip = asciicode();
584 		else
585 			*uip = asciicode();
586 		return (0);
587 	}
588 	rval = 0;
589 	errno = 0;
590 	if (signedconv)
591 		*ip = strtoimax(*gargv, &ep, 0);
592 	else
593 		*uip = strtoumax(*gargv, &ep, 0);
594 	if (ep == *gargv) {
595 		warnx("%s: expected numeric value", *gargv);
596 		rval = 1;
597 	}
598 	else if (*ep != '\0') {
599 		warnx("%s: not completely converted", *gargv);
600 		rval = 1;
601 	}
602 	if (errno == ERANGE) {
603 		warnx("%s: %s", *gargv, strerror(ERANGE));
604 		rval = 1;
605 	}
606 	++gargv;
607 	return (rval);
608 }
609 
610 static int
611 getfloating(long double *dp, int mod_ldbl)
612 {
613 	char *ep;
614 	int rval;
615 
616 	if (!*gargv) {
617 		*dp = 0.0;
618 		return (0);
619 	}
620 	if (**gargv == '"' || **gargv == '\'') {
621 		*dp = asciicode();
622 		return (0);
623 	}
624 	rval = 0;
625 	errno = 0;
626 	if (mod_ldbl)
627 		*dp = strtold(*gargv, &ep);
628 	else
629 		*dp = strtod(*gargv, &ep);
630 	if (ep == *gargv) {
631 		warnx("%s: expected numeric value", *gargv);
632 		rval = 1;
633 	} else if (*ep != '\0') {
634 		warnx("%s: not completely converted", *gargv);
635 		rval = 1;
636 	}
637 	if (errno == ERANGE) {
638 		warnx("%s: %s", *gargv, strerror(ERANGE));
639 		rval = 1;
640 	}
641 	++gargv;
642 	return (rval);
643 }
644 
645 static int
646 asciicode(void)
647 {
648 	int ch;
649 	wchar_t wch;
650 	mbstate_t mbs;
651 
652 	ch = (unsigned char)**gargv;
653 	if (ch == '\'' || ch == '"') {
654 		memset(&mbs, 0, sizeof(mbs));
655 		switch (mbrtowc(&wch, *gargv + 1, MB_LEN_MAX, &mbs)) {
656 		case (size_t)-2:
657 		case (size_t)-1:
658 			wch = (unsigned char)gargv[0][1];
659 			break;
660 		case 0:
661 			wch = 0;
662 			break;
663 		}
664 		ch = wch;
665 	}
666 	++gargv;
667 	return (ch);
668 }
669 
670 static void
671 usage(void)
672 {
673 	(void)fprintf(stderr, "usage: printf format [arguments ...]\n");
674 }
675