xref: /netbsd-src/usr.bin/printf/printf.c (revision d3d2abdc28a790079ac0d9b337b15bd97b65d751)
1 /*	$NetBSD: printf.c,v 1.49 2019/07/21 15:25:39 kre Exp $	*/
2 
3 /*
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  * 3. 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 #include <sys/cdefs.h>
33 #ifndef lint
34 #if !defined(BUILTIN) && !defined(SHELL)
35 __COPYRIGHT("@(#) Copyright (c) 1989, 1993\
36  The Regents of the University of California.  All rights reserved.");
37 #endif
38 #endif
39 
40 #ifndef lint
41 #if 0
42 static char sccsid[] = "@(#)printf.c	8.2 (Berkeley) 3/22/95";
43 #else
44 __RCSID("$NetBSD: printf.c,v 1.49 2019/07/21 15:25:39 kre Exp $");
45 #endif
46 #endif /* not lint */
47 
48 #include <sys/types.h>
49 
50 #include <ctype.h>
51 #include <err.h>
52 #include <errno.h>
53 #include <inttypes.h>
54 #include <limits.h>
55 #include <locale.h>
56 #include <stdarg.h>
57 #include <stdio.h>
58 #include <stdlib.h>
59 #include <string.h>
60 #include <unistd.h>
61 
62 #ifdef __GNUC__
63 #define ESCAPE '\e'
64 #else
65 #define ESCAPE 033
66 #endif
67 
68 static void	 conv_escape_str(char *, void (*)(int), int);
69 static char	*conv_escape(char *, char *, int);
70 static char	*conv_expand(const char *);
71 static char	 getchr(void);
72 static double	 getdouble(void);
73 static int	 getwidth(void);
74 static intmax_t	 getintmax(void);
75 static char	*getstr(void);
76 static char	*mklong(const char *, char);
77 static void      check_conversion(const char *, const char *);
78 static void	 usage(void);
79 
80 static void	b_count(int);
81 static void	b_output(int);
82 static size_t	b_length;
83 static char	*b_fmt;
84 
85 static int	rval;
86 static char  **gargv;
87 
88 #ifdef BUILTIN		/* csh builtin */
89 #define main progprintf
90 #endif
91 
92 #ifdef SHELL		/* sh (aka ash) builtin */
93 #define main printfcmd
94 #include "../../bin/sh/bltin/bltin.h"
95 #endif /* SHELL */
96 
97 #define PF(f, func) { \
98 	if (fieldwidth != -1) { \
99 		if (precision != -1) \
100 			error = printf(f, fieldwidth, precision, func); \
101 		else \
102 			error = printf(f, fieldwidth, func); \
103 	} else if (precision != -1) \
104 		error = printf(f, precision, func); \
105 	else \
106 		error = printf(f, func); \
107 }
108 
109 #define APF(cpp, f, func) { \
110 	if (fieldwidth != -1) { \
111 		if (precision != -1) \
112 			error = asprintf(cpp, f, fieldwidth, precision, func); \
113 		else \
114 			error = asprintf(cpp, f, fieldwidth, func); \
115 	} else if (precision != -1) \
116 		error = asprintf(cpp, f, precision, func); \
117 	else \
118 		error = asprintf(cpp, f, func); \
119 }
120 
121 #ifdef main
122 int main(int, char *[]);
123 #endif
124 
125 int
126 main(int argc, char *argv[])
127 {
128 	char *fmt, *start;
129 	int fieldwidth, precision;
130 	char nextch;
131 	char *format;
132 	char ch;
133 	int error;
134 
135 #if !defined(SHELL) && !defined(BUILTIN)
136 	(void)setlocale (LC_ALL, "");
137 #endif
138 
139 	rval = 0;	/* clear for builtin versions (avoid holdover) */
140 
141 #if 0
142 	int o;
143 
144 	/*
145 	 * printf does not comply with Posix XBD 12.2 - there are no opts,
146 	 * not even the -- end of options marker.   Do not run getoot().
147 	 */
148 	while ((o = getopt(argc, argv, "")) != -1) {
149 		switch (o) {
150 		case '?':
151 		default:
152 			usage();
153 			return 1;
154 		}
155 	}
156 	argc -= optind;
157 	argv += optind;
158 #else
159 	argc -= 1;
160 	argv += 1;
161 #endif
162 
163 	if (argc < 1) {
164 		usage();
165 		return 1;
166 	}
167 
168 	format = *argv;
169 	gargv = ++argv;
170 
171 #define SKIP1	"#-+ 0'"
172 #define SKIP2	"0123456789"
173 	do {
174 		/*
175 		 * Basic algorithm is to scan the format string for conversion
176 		 * specifications -- once one is found, find out if the field
177 		 * width or precision is a '*'; if it is, gather up value.
178 		 * Note, format strings are reused as necessary to use up the
179 		 * provided arguments, arguments of zero/null string are
180 		 * provided to use up the format string.
181 		 */
182 
183 		/* find next format specification */
184 		for (fmt = format; (ch = *fmt++) != '\0';) {
185 			if (ch == '\\') {
186 				char c_ch;
187 				fmt = conv_escape(fmt, &c_ch, 0);
188 				putchar(c_ch);
189 				continue;
190 			}
191 			if (ch != '%' || (*fmt == '%' && ++fmt)) {
192 				(void)putchar(ch);
193 				continue;
194 			}
195 
196 			/*
197 			 * Ok - we've found a format specification,
198 			 * Save its address for a later printf().
199 			 */
200 			start = fmt - 1;
201 
202 			/* skip to field width */
203 			fmt += strspn(fmt, SKIP1);
204 			if (*fmt == '*') {
205 				fmt++;
206 				fieldwidth = getwidth();
207 			} else {
208 				fieldwidth = -1;
209 
210 				/* skip to possible '.' for precision */
211 				fmt += strspn(fmt, SKIP2);
212 			}
213 
214 			if (*fmt == '.') {
215 				 /* get following precision */
216 				fmt++;
217 				if (*fmt == '*') {
218 					fmt++;
219 					precision = getwidth();
220 				} else {
221 					precision = -1;
222 					fmt += strspn(fmt, SKIP2);
223 				}
224 			} else
225 				precision = -1;
226 
227 			ch = *fmt;
228 			if (!ch) {
229 				warnx("%s: missing format character", start);
230 				return 1;
231 			}
232 
233 			/*
234 			 * null terminate format string to we can use it
235 			 * as an argument to printf.
236 			 */
237 			nextch = fmt[1];
238 			fmt[1] = 0;
239 
240 			switch (ch) {
241 
242 			case 'B': {
243 				const char *p = conv_expand(getstr());
244 
245 				if (p == NULL)
246 					goto out;
247 				*fmt = 's';
248 				PF(start, p);
249 				if (error < 0)
250 					goto out;
251 				break;
252 			}
253 			case 'b': {
254 				/*
255 				 * There has to be a better way to do this,
256 				 * but the string we generate might have
257 				 * embedded nulls
258 				 */
259 				static char *a, *t;
260 				char *cp = getstr();
261 
262 				/* Free on entry in case shell longjumped out */
263 				if (a != NULL)
264 					free(a);
265 				a = NULL;
266 				if (t != NULL)
267 					free(t);
268 				t = NULL;
269 
270 				/* Count number of bytes we want to output */
271 				b_length = 0;
272 				conv_escape_str(cp, b_count, 0);
273 				t = malloc(b_length + 1);
274 				if (t == NULL)
275 					goto out;
276 				(void)memset(t, 'x', b_length);
277 				t[b_length] = 0;
278 
279 				/* Get printf to calculate the lengths */
280 				*fmt = 's';
281 				APF(&a, start, t);
282 				if (error == -1)
283 					goto out;
284 				b_fmt = a;
285 
286 				/* Output leading spaces and data bytes */
287 				conv_escape_str(cp, b_output, 1);
288 
289 				/* Add any trailing spaces */
290 				printf("%s", b_fmt);
291 				break;
292 			}
293 			case 'c': {
294 				char p = getchr();
295 
296 				PF(start, p);
297 				if (error < 0)
298 					goto out;
299 				break;
300 			}
301 			case 's': {
302 				char *p = getstr();
303 
304 				PF(start, p);
305 				if (error < 0)
306 					goto out;
307 				break;
308 			}
309 			case 'd':
310 			case 'i': {
311 				intmax_t p = getintmax();
312 				char *f = mklong(start, ch);
313 
314 				PF(f, p);
315 				if (error < 0)
316 					goto out;
317 				break;
318 			}
319 			case 'o':
320 			case 'u':
321 			case 'x':
322 			case 'X': {
323 				uintmax_t p = (uintmax_t)getintmax();
324 				char *f = mklong(start, ch);
325 
326 				PF(f, p);
327 				if (error < 0)
328 					goto out;
329 				break;
330 			}
331 			case 'a':
332 			case 'A':
333 			case 'e':
334 			case 'E':
335 			case 'f':
336 			case 'F':
337 			case 'g':
338 			case 'G': {
339 				double p = getdouble();
340 
341 				PF(start, p);
342 				if (error < 0)
343 					goto out;
344 				break;
345 			}
346 			case '%':
347 				/* Don't ask, but this is useful ... */
348 				if (fieldwidth == 'N' && precision == 'B')
349 					return 0;
350 				/* FALLTHROUGH */
351 			default:
352 				warnx("%s: invalid directive", start);
353 				return 1;
354 			}
355 			*fmt++ = ch;
356 			*fmt = nextch;
357 			/* escape if a \c was encountered */
358 			if (rval & 0x100)
359 				return rval & ~0x100;
360 		}
361 	} while (gargv != argv && *gargv);
362 
363 	return rval & ~0x100;
364   out:
365 	warn("print failed");
366 	return 1;
367 }
368 
369 /* helper functions for conv_escape_str */
370 
371 static void
372 /*ARGSUSED*/
373 b_count(int ch)
374 {
375 	b_length++;
376 }
377 
378 /* Output one converted character for every 'x' in the 'format' */
379 
380 static void
381 b_output(int ch)
382 {
383 	for (;;) {
384 		switch (*b_fmt++) {
385 		case 0:
386 			b_fmt--;
387 			return;
388 		case ' ':
389 			putchar(' ');
390 			break;
391 		default:
392 			putchar(ch);
393 			return;
394 		}
395 	}
396 }
397 
398 
399 /*
400  * Print SysV echo(1) style escape string
401  *	Halts processing string if a \c escape is encountered.
402  */
403 static void
404 conv_escape_str(char *str, void (*do_putchar)(int), int quiet)
405 {
406 	int value;
407 	int ch;
408 	char c;
409 
410 	while ((ch = *str++) != '\0') {
411 		if (ch != '\\') {
412 			do_putchar(ch);
413 			continue;
414 		}
415 
416 		ch = *str++;
417 		if (ch == 'c') {
418 			/* \c as in SYSV echo - abort all processing.... */
419 			rval |= 0x100;
420 			break;
421 		}
422 
423 		/*
424 		 * %b string octal constants are not like those in C.
425 		 * They start with a \0, and are followed by 0, 1, 2,
426 		 * or 3 octal digits.
427 		 */
428 		if (ch == '0') {
429 			int octnum = 0, i;
430 			for (i = 0; i < 3; i++) {
431 				if (!isdigit((unsigned char)*str) || *str > '7')
432 					break;
433 				octnum = (octnum << 3) | (*str++ - '0');
434 			}
435 			do_putchar(octnum);
436 			continue;
437 		}
438 
439 		/* \[M][^|-]C as defined by vis(3) */
440 		if (ch == 'M' && *str == '-') {
441 			do_putchar(0200 | str[1]);
442 			str += 2;
443 			continue;
444 		}
445 		if (ch == 'M' && *str == '^') {
446 			str++;
447 			value = 0200;
448 			ch = '^';
449 		} else
450 			value = 0;
451 		if (ch == '^') {
452 			ch = *str++;
453 			if (ch == '?')
454 				value |= 0177;
455 			else
456 				value |= ch & 037;
457 			do_putchar(value);
458 			continue;
459 		}
460 
461 		/* Finally test for sequences valid in the format string */
462 		str = conv_escape(str - 1, &c, quiet);
463 		do_putchar(c);
464 	}
465 }
466 
467 /*
468  * Print "standard" escape characters
469  */
470 static char *
471 conv_escape(char *str, char *conv_ch, int quiet)
472 {
473 	char value;
474 	char ch;
475 	char num_buf[4], *num_end;
476 
477 	ch = *str++;
478 
479 	switch (ch) {
480 	case '\0':
481 		if (!quiet)
482 			warnx("incomplete escape sequence");
483 		rval = 1;
484 		value = '\\';
485 		--str;
486 		break;
487 
488 	case '0': case '1': case '2': case '3':
489 	case '4': case '5': case '6': case '7':
490 		num_buf[0] = ch;
491 		ch = str[0];
492 		num_buf[1] = ch;
493 		num_buf[2] = (char)(ch != '\0' ? str[1] : '\0');
494 		num_buf[3] = '\0';
495 		value = (char)strtoul(num_buf, &num_end, 8);
496 		str += num_end  - (num_buf + 1);
497 		break;
498 
499 	case 'x':
500 		/*
501 		 * Hexadecimal character constants are not required to be
502 		 * supported (by SuS v1) because there is no consistent
503 		 * way to detect the end of the constant.
504 		 * Supporting 2 byte constants is a compromise.
505 		 */
506 		ch = str[0];
507 		num_buf[0] = ch;
508 		num_buf[1] = (char)(ch != '\0' ? str[1] : '\0');
509 		num_buf[2] = '\0';
510 		value = (char)strtoul(num_buf, &num_end, 16);
511 		str += num_end - num_buf;
512 		break;
513 
514 	case '\\':	value = '\\';	break;	/* backslash */
515 	case '\'':	value = '\'';	break;	/* single quote */
516 	case '"':	value = '"';	break;	/* double quote */
517 	case 'a':	value = '\a';	break;	/* alert */
518 	case 'b':	value = '\b';	break;	/* backspace */
519 	case 'e':	value = ESCAPE;	break;	/* escape */
520 	case 'E':	value = ESCAPE;	break;	/* escape */
521 	case 'f':	value = '\f';	break;	/* form-feed */
522 	case 'n':	value = '\n';	break;	/* newline */
523 	case 'r':	value = '\r';	break;	/* carriage-return */
524 	case 't':	value = '\t';	break;	/* tab */
525 	case 'v':	value = '\v';	break;	/* vertical-tab */
526 
527 	default:
528 		if (!quiet)
529 			warnx("unknown escape sequence `\\%c'", ch);
530 		rval = 1;
531 		value = ch;
532 		break;
533 	}
534 
535 	*conv_ch = value;
536 	return str;
537 }
538 
539 /* expand a string so that everything is printable */
540 
541 static char *
542 conv_expand(const char *str)
543 {
544 	static char *conv_str;
545 	char *cp;
546 	char ch;
547 
548 	if (conv_str)
549 		free(conv_str);
550 	/* get a buffer that is definitely large enough.... */
551 	conv_str = malloc(4 * strlen(str) + 1);
552 	if (!conv_str)
553 		return NULL;
554 	cp = conv_str;
555 
556 	while ((ch = *(const char *)str++) != '\0') {
557 		switch (ch) {
558 		/* Use C escapes for expected control characters */
559 		case '\\':	ch = '\\';	break;	/* backslash */
560 		case '\'':	ch = '\'';	break;	/* single quote */
561 		case '"':	ch = '"';	break;	/* double quote */
562 		case '\a':	ch = 'a';	break;	/* alert */
563 		case '\b':	ch = 'b';	break;	/* backspace */
564 		case ESCAPE:	ch = 'e';	break;	/* escape */
565 		case '\f':	ch = 'f';	break;	/* form-feed */
566 		case '\n':	ch = 'n';	break;	/* newline */
567 		case '\r':	ch = 'r';	break;	/* carriage-return */
568 		case '\t':	ch = 't';	break;	/* tab */
569 		case '\v':	ch = 'v';	break;	/* vertical-tab */
570 		default:
571 			/* Copy anything printable */
572 			if (isprint((unsigned char)ch)) {
573 				*cp++ = ch;
574 				continue;
575 			}
576 			/* Use vis(3) encodings for the rest */
577 			*cp++ = '\\';
578 			if (ch & 0200) {
579 				*cp++ = 'M';
580 				ch &= (char)~0200;
581 			}
582 			if (ch == 0177) {
583 				*cp++ = '^';
584 				*cp++ = '?';
585 				continue;
586 			}
587 			if (ch < 040) {
588 				*cp++ = '^';
589 				*cp++ = ch | 0100;
590 				continue;
591 			}
592 			*cp++ = '-';
593 			*cp++ = ch;
594 			continue;
595 		}
596 		*cp++ = '\\';
597 		*cp++ = ch;
598 	}
599 
600 	*cp = 0;
601 	return conv_str;
602 }
603 
604 static char *
605 mklong(const char *str, char ch)
606 {
607 	static char copy[64];
608 	size_t len;
609 
610 	len = strlen(str) + 2;
611 	if (len > sizeof copy) {
612 		warnx("format %s too complex", str);
613 		len = 4;
614 	}
615 	(void)memmove(copy, str, len - 3);
616 	copy[len - 3] = 'j';
617 	copy[len - 2] = ch;
618 	copy[len - 1] = '\0';
619 	return copy;
620 }
621 
622 static char
623 getchr(void)
624 {
625 	if (!*gargv)
626 		return 0;
627 	return **gargv++;
628 }
629 
630 static char *
631 getstr(void)
632 {
633 	static char empty[] = "";
634 	if (!*gargv)
635 		return empty;
636 	return *gargv++;
637 }
638 
639 static int
640 getwidth(void)
641 {
642 	unsigned long val;
643 	char *s, *ep;
644 
645 	s = *gargv;
646 	if (s == NULL)
647 		return 0;
648 	gargv++;
649 
650 	errno = 0;
651 	val = strtoul(s, &ep, 0);
652 	check_conversion(s, ep);
653 
654 	/* Arbitrarily 'restrict' field widths to 1Mbyte */
655 	if (val > 1 << 20) {
656 		warnx("%s: invalid field width", s);
657 		return 0;
658 	}
659 
660 	return (int)val;
661 }
662 
663 static intmax_t
664 getintmax(void)
665 {
666 	intmax_t val;
667 	char *cp, *ep;
668 
669 	cp = *gargv;
670 	if (cp == NULL)
671 		return 0;
672 	gargv++;
673 
674 	if (*cp == '\"' || *cp == '\'')
675 		return *(cp + 1);
676 
677 	errno = 0;
678 	val = strtoimax(cp, &ep, 0);
679 	check_conversion(cp, ep);
680 	return val;
681 }
682 
683 static double
684 getdouble(void)
685 {
686 	double val;
687 	char *ep;
688 
689 	if (!*gargv)
690 		return 0.0;
691 
692 	if (**gargv == '\"' || **gargv == '\'')
693 		return (double) *((*gargv++)+1);
694 
695 	errno = 0;
696 	val = strtod(*gargv, &ep);
697 	check_conversion(*gargv++, ep);
698 	return val;
699 }
700 
701 static void
702 check_conversion(const char *s, const char *ep)
703 {
704 	if (*ep) {
705 		if (ep == s)
706 			warnx("%s: expected numeric value", s);
707 		else
708 			warnx("%s: not completely converted", s);
709 		rval = 1;
710 	} else if (errno == ERANGE) {
711 		warnx("%s: %s", s, strerror(ERANGE));
712 		rval = 1;
713 	}
714 }
715 
716 static void
717 usage(void)
718 {
719 	(void)fprintf(stderr, "Usage: %s format [arg ...]\n", getprogname());
720 }
721