xref: /netbsd-src/usr.bin/printf/printf.c (revision 466a16a118933bd295a8a104f095714fadf9cf68)
1 /*	$NetBSD: printf.c,v 1.33 2008/07/21 14:19:24 lukem 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 1.33 2008/07/21 14:19:24 lukem 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));
69 static char	*conv_escape(char *, char *);
70 static char	*conv_expand(const char *);
71 static int	 getchr(void);
72 static double	 getdouble(void);
73 static int	 getwidth(void);
74 static intmax_t	 getintmax(void);
75 static uintmax_t getuintmax(void);
76 static char	*getstr(void);
77 static char	*mklong(const char *, int);
78 static void      check_conversion(const char *, const char *);
79 static void	 usage(void);
80 
81 static void	b_count(int);
82 static void	b_output(int);
83 static size_t	b_length;
84 static char	*b_fmt;
85 
86 static int	rval;
87 static char  **gargv;
88 
89 #ifdef BUILTIN		/* csh builtin */
90 #define main progprintf
91 #endif
92 
93 #ifdef SHELL		/* sh (aka ash) builtin */
94 #define main printfcmd
95 #include "../../bin/sh/bltin/bltin.h"
96 #endif /* SHELL */
97 
98 #define PF(f, func) { \
99 	if (fieldwidth != -1) { \
100 		if (precision != -1) \
101 			error = printf(f, fieldwidth, precision, func); \
102 		else \
103 			error = printf(f, fieldwidth, func); \
104 	} else if (precision != -1) \
105 		error = printf(f, precision, func); \
106 	else \
107 		error = printf(f, func); \
108 }
109 
110 #define APF(cpp, f, func) { \
111 	if (fieldwidth != -1) { \
112 		if (precision != -1) \
113 			error = asprintf(cpp, f, fieldwidth, precision, func); \
114 		else \
115 			error = asprintf(cpp, f, fieldwidth, func); \
116 	} else if (precision != -1) \
117 		error = asprintf(cpp, f, precision, func); \
118 	else \
119 		error = asprintf(cpp, f, func); \
120 }
121 
122 #ifdef main
123 int main(int, char *[]);
124 #endif
125 int main(int argc, char *argv[])
126 {
127 	char *fmt, *start;
128 	int fieldwidth, precision;
129 	char nextch;
130 	char *format;
131 	int ch;
132 	int error;
133 
134 #if !defined(SHELL) && !defined(BUILTIN)
135 	(void)setlocale (LC_ALL, "");
136 #endif
137 
138 	while ((ch = getopt(argc, argv, "")) != -1) {
139 		switch (ch) {
140 		case '?':
141 		default:
142 			usage();
143 			return 1;
144 		}
145 	}
146 	argc -= optind;
147 	argv += optind;
148 
149 	if (argc < 1) {
150 		usage();
151 		return 1;
152 	}
153 
154 	format = *argv;
155 	gargv = ++argv;
156 
157 #define SKIP1	"#-+ 0"
158 #define SKIP2	"*0123456789"
159 	do {
160 		/*
161 		 * Basic algorithm is to scan the format string for conversion
162 		 * specifications -- once one is found, find out if the field
163 		 * width or precision is a '*'; if it is, gather up value.
164 		 * Note, format strings are reused as necessary to use up the
165 		 * provided arguments, arguments of zero/null string are
166 		 * provided to use up the format string.
167 		 */
168 
169 		/* find next format specification */
170 		for (fmt = format; (ch = *fmt++) != '\0';) {
171 			if (ch == '\\') {
172 				char c_ch;
173 				fmt = conv_escape(fmt, &c_ch);
174 				putchar(c_ch);
175 				continue;
176 			}
177 			if (ch != '%' || (*fmt == '%' && ++fmt)) {
178 				(void)putchar(ch);
179 				continue;
180 			}
181 
182 			/* Ok - we've found a format specification,
183 			   Save its address for a later printf(). */
184 			start = fmt - 1;
185 
186 			/* skip to field width */
187 			fmt += strspn(fmt, SKIP1);
188 			fieldwidth = *fmt == '*' ? getwidth() : -1;
189 
190 			/* skip to possible '.', get following precision */
191 			fmt += strspn(fmt, SKIP2);
192 			if (*fmt == '.')
193 				++fmt;
194 			precision = *fmt == '*' ? getwidth() : -1;
195 
196 			fmt += strspn(fmt, SKIP2);
197 
198 			ch = *fmt;
199 			if (!ch) {
200 				warnx("missing format character");
201 				return (1);
202 			}
203 			/* null terminate format string to we can use it
204 			   as an argument to printf. */
205 			nextch = fmt[1];
206 			fmt[1] = 0;
207 			switch (ch) {
208 
209 			case 'B': {
210 				const char *p = conv_expand(getstr());
211 				if (p == NULL)
212 					goto out;
213 				*fmt = 's';
214 				PF(start, p);
215 				if (error < 0)
216 					goto out;
217 				break;
218 			}
219 			case 'b': {
220 				/* There has to be a better way to do this,
221 				 * but the string we generate might have
222 				 * embedded nulls. */
223 				static char *a, *t;
224 				char *cp = getstr();
225 				/* Free on entry in case shell longjumped out */
226 				if (a != NULL)
227 					free(a);
228 				a = NULL;
229 				if (t != NULL)
230 					free(t);
231 				t = NULL;
232 				/* Count number of bytes we want to output */
233 				b_length = 0;
234 				conv_escape_str(cp, b_count);
235 				t = malloc(b_length + 1);
236 				if (t == NULL)
237 					goto out;
238 				(void)memset(t, 'x', b_length);
239 				t[b_length] = 0;
240 				/* Get printf to calculate the lengths */
241 				*fmt = 's';
242 				APF(&a, start, t);
243 				if (error == -1)
244 					goto out;
245 				b_fmt = a;
246 				/* Output leading spaces and data bytes */
247 				conv_escape_str(cp, b_output);
248 				/* Add any trailing spaces */
249 				printf("%s", b_fmt);
250 				break;
251 			}
252 			case 'c': {
253 				char p = getchr();
254 				PF(start, p);
255 				if (error < 0)
256 					goto out;
257 				break;
258 			}
259 			case 's': {
260 				char *p = getstr();
261 				PF(start, p);
262 				if (error < 0)
263 					goto out;
264 				break;
265 			}
266 			case 'd':
267 			case 'i': {
268 				intmax_t p = getintmax();
269 				char *f = mklong(start, ch);
270 				PF(f, p);
271 				if (error < 0)
272 					goto out;
273 				break;
274 			}
275 			case 'o':
276 			case 'u':
277 			case 'x':
278 			case 'X': {
279 				uintmax_t p = getuintmax();
280 				char *f = mklong(start, ch);
281 				PF(f, p);
282 				if (error < 0)
283 					goto out;
284 				break;
285 			}
286 			case 'e':
287 			case 'E':
288 			case 'f':
289 			case 'g':
290 			case 'G': {
291 				double p = getdouble();
292 				PF(start, p);
293 				if (error < 0)
294 					goto out;
295 				break;
296 			}
297 			default:
298 				warnx("%s: invalid directive", start);
299 				return 1;
300 			}
301 			*fmt++ = ch;
302 			*fmt = nextch;
303 			/* escape if a \c was encountered */
304 			if (rval & 0x100)
305 				return rval & ~0x100;
306 		}
307 	} while (gargv != argv && *gargv);
308 
309 	return rval & ~0x100;
310 out:
311 	warn("print failed");
312 	return 1;
313 }
314 
315 /* helper functions for conv_escape_str */
316 
317 static void
318 /*ARGSUSED*/
319 b_count(int ch)
320 {
321 	b_length++;
322 }
323 
324 /* Output one converted character for every 'x' in the 'format' */
325 
326 static void
327 b_output(int ch)
328 {
329 	for (;;) {
330 		switch (*b_fmt++) {
331 		case 0:
332 			b_fmt--;
333 			return;
334 		case ' ':
335 			putchar(' ');
336 			break;
337 		default:
338 			putchar(ch);
339 			return;
340 		}
341 	}
342 }
343 
344 
345 /*
346  * Print SysV echo(1) style escape string
347  *	Halts processing string if a \c escape is encountered.
348  */
349 static void
350 conv_escape_str(char *str, void (*do_putchar)(int))
351 {
352 	int value;
353 	int ch;
354 	char c;
355 
356 	while ((ch = *str++) != '\0') {
357 		if (ch != '\\') {
358 			do_putchar(ch);
359 			continue;
360 		}
361 
362 		ch = *str++;
363 		if (ch == 'c') {
364 			/* \c as in SYSV echo - abort all processing.... */
365 			rval |= 0x100;
366 			break;
367 		}
368 
369 		/*
370 		 * %b string octal constants are not like those in C.
371 		 * They start with a \0, and are followed by 0, 1, 2,
372 		 * or 3 octal digits.
373 		 */
374 		if (ch == '0') {
375 			int octnum = 0, i;
376 			for (i = 0; i < 3; i++) {
377 				if (!isdigit((unsigned char)*str) || *str > '7')
378 					break;
379 				octnum = (octnum << 3) | (*str++ - '0');
380 			}
381 			do_putchar(octnum);
382 			continue;
383 		}
384 
385 		/* \[M][^|-]C as defined by vis(3) */
386 		if (ch == 'M' && *str == '-') {
387 			do_putchar(0200 | str[1]);
388 			str += 2;
389 			continue;
390 		}
391 		if (ch == 'M' && *str == '^') {
392 			str++;
393 			value = 0200;
394 			ch = '^';
395 		} else
396 			value = 0;
397 		if (ch == '^') {
398 			ch = *str++;
399 			if (ch == '?')
400 				value |= 0177;
401 			else
402 				value |= ch & 037;
403 			do_putchar(value);
404 			continue;
405 		}
406 
407 		/* Finally test for sequences valid in the format string */
408 		str = conv_escape(str - 1, &c);
409 		do_putchar(c);
410 	}
411 }
412 
413 /*
414  * Print "standard" escape characters
415  */
416 static char *
417 conv_escape(char *str, char *conv_ch)
418 {
419 	int value;
420 	int ch;
421 	char num_buf[4], *num_end;
422 
423 	ch = *str++;
424 
425 	switch (ch) {
426 	case '0': case '1': case '2': case '3':
427 	case '4': case '5': case '6': case '7':
428 		num_buf[0] = ch;
429 		ch = str[0];
430 		num_buf[1] = ch;
431 		num_buf[2] = ch ? str[1] : 0;
432 		num_buf[3] = 0;
433 		value = strtoul(num_buf, &num_end, 8);
434 		str += num_end  - (num_buf + 1);
435 		break;
436 
437 	case 'x':
438 		/* Hexadecimal character constants are not required to be
439 		   supported (by SuS v1) because there is no consistent
440 		   way to detect the end of the constant.
441 		   Supporting 2 byte constants is a compromise. */
442 		ch = str[0];
443 		num_buf[0] = ch;
444 		num_buf[1] = ch ? str[1] : 0;
445 		num_buf[2] = 0;
446 		value = strtoul(num_buf, &num_end, 16);
447 		str += num_end - num_buf;
448 		break;
449 
450 	case '\\':	value = '\\';	break;	/* backslash */
451 	case '\'':	value = '\'';	break;	/* single quote */
452 	case '"':	value = '"';	break;	/* double quote */
453 	case 'a':	value = '\a';	break;	/* alert */
454 	case 'b':	value = '\b';	break;	/* backspace */
455 	case 'e':	value = ESCAPE;	break;	/* escape */
456 	case 'f':	value = '\f';	break;	/* form-feed */
457 	case 'n':	value = '\n';	break;	/* newline */
458 	case 'r':	value = '\r';	break;	/* carriage-return */
459 	case 't':	value = '\t';	break;	/* tab */
460 	case 'v':	value = '\v';	break;	/* vertical-tab */
461 
462 	default:
463 		warnx("unknown escape sequence `\\%c'", ch);
464 		rval = 1;
465 		value = ch;
466 		break;
467 	}
468 
469 	*conv_ch = value;
470 	return str;
471 }
472 
473 /* expand a string so that everything is printable */
474 
475 static char *
476 conv_expand(const char *str)
477 {
478 	static char *conv_str;
479 	char *cp;
480 	int ch;
481 
482 	if (conv_str)
483 		free(conv_str);
484 	/* get a buffer that is definitely large enough.... */
485 	conv_str = malloc(4 * strlen(str) + 1);
486 	if (!conv_str)
487 		return NULL;
488 	cp = conv_str;
489 
490 	while ((ch = *(const unsigned char *)str++) != '\0') {
491 		switch (ch) {
492 		/* Use C escapes for expected control characters */
493 		case '\\':	ch = '\\';	break;	/* backslash */
494 		case '\'':	ch = '\'';	break;	/* single quote */
495 		case '"':	ch = '"';	break;	/* double quote */
496 		case '\a':	ch = 'a';	break;	/* alert */
497 		case '\b':	ch = 'b';	break;	/* backspace */
498 		case ESCAPE:	ch = 'e';	break;	/* escape */
499 		case '\f':	ch = 'f';	break;	/* form-feed */
500 		case '\n':	ch = 'n';	break;	/* newline */
501 		case '\r':	ch = 'r';	break;	/* carriage-return */
502 		case '\t':	ch = 't';	break;	/* tab */
503 		case '\v':	ch = 'v';	break;	/* vertical-tab */
504 		default:
505 			/* Copy anything printable */
506 			if (isprint(ch)) {
507 				*cp++ = ch;
508 				continue;
509 			}
510 			/* Use vis(3) encodings for the rest */
511 			*cp++ = '\\';
512 			if (ch & 0200) {
513 				*cp++ = 'M';
514 				ch &= ~0200;
515 			}
516 			if (ch == 0177) {
517 				*cp++ = '^';
518 				*cp++ = '?';
519 				continue;
520 			}
521 			if (ch < 040) {
522 				*cp++ = '^';
523 				*cp++ = ch | 0100;
524 				continue;
525 			}
526 			*cp++ = '-';
527 			*cp++ = ch;
528 			continue;
529 		}
530 		*cp++ = '\\';
531 		*cp++ = ch;
532 	}
533 
534 	*cp = 0;
535 	return conv_str;
536 }
537 
538 static char *
539 mklong(const char *str, int ch)
540 {
541 	static char copy[64];
542 	size_t len;
543 
544 	len = strlen(str) + 2;
545 	if (len > sizeof copy) {
546 		warnx("format %s too complex\n", str);
547 		len = 4;
548 	}
549 	(void)memmove(copy, str, len - 3);
550 	copy[len - 3] = 'j';
551 	copy[len - 2] = ch;
552 	copy[len - 1] = '\0';
553 	return copy;
554 }
555 
556 static int
557 getchr(void)
558 {
559 	if (!*gargv)
560 		return 0;
561 	return (int)**gargv++;
562 }
563 
564 static char *
565 getstr(void)
566 {
567 	static char empty[] = "";
568 	if (!*gargv)
569 		return empty;
570 	return *gargv++;
571 }
572 
573 static int
574 getwidth(void)
575 {
576 	long val;
577 	char *s, *ep;
578 
579 	s = *gargv;
580 	if (!*gargv)
581 		return (0);
582 	gargv++;
583 
584 	errno = 0;
585 	val = strtoul(s, &ep, 0);
586 	check_conversion(s, ep);
587 
588 	/* Arbitrarily 'restrict' field widths to 1Mbyte */
589 	if (val < 0 || val > 1 << 20) {
590 		warnx("%s: invalid field width", s);
591 		return 0;
592 	}
593 
594 	return val;
595 }
596 
597 static intmax_t
598 getintmax(void)
599 {
600 	intmax_t val;
601 	char *cp, *ep;
602 
603 	cp = *gargv;
604 	if (cp == NULL)
605 		return 0;
606 	gargv++;
607 
608 	if (*cp == '\"' || *cp == '\'')
609 		return *(cp+1);
610 
611 	errno = 0;
612 	val = strtoimax(cp, &ep, 0);
613 	check_conversion(cp, ep);
614 	return val;
615 }
616 
617 static uintmax_t
618 getuintmax(void)
619 {
620 	uintmax_t val;
621 	char *cp, *ep;
622 
623 	cp = *gargv;
624 	if (cp == NULL)
625 		return 0;
626 	gargv++;
627 
628 	if (*cp == '\"' || *cp == '\'')
629 		return *(cp + 1);
630 
631 	/* strtoumax won't error -ve values */
632 	while (isspace(*(unsigned char *)cp))
633 		cp++;
634 	if (*cp == '-') {
635 		warnx("%s: expected positive numeric value", cp);
636 		rval = 1;
637 		return 0;
638 	}
639 
640 	errno = 0;
641 	val = strtoumax(cp, &ep, 0);
642 	check_conversion(cp, ep);
643 	return val;
644 }
645 
646 static double
647 getdouble(void)
648 {
649 	double val;
650 	char *ep;
651 
652 	if (!*gargv)
653 		return (0.0);
654 
655 	if (**gargv == '\"' || **gargv == '\'')
656 		return (double) *((*gargv++)+1);
657 
658 	errno = 0;
659 	val = strtod(*gargv, &ep);
660 	check_conversion(*gargv++, ep);
661 	return val;
662 }
663 
664 static void
665 check_conversion(const char *s, const char *ep)
666 {
667 	if (*ep) {
668 		if (ep == s)
669 			warnx("%s: expected numeric value", s);
670 		else
671 			warnx("%s: not completely converted", s);
672 		rval = 1;
673 	} else if (errno == ERANGE) {
674 		warnx("%s: %s", s, strerror(ERANGE));
675 		rval = 1;
676 	}
677 }
678 
679 static void
680 usage(void)
681 {
682 	(void)fprintf(stderr, "Usage: %s format [arg ...]\n", getprogname());
683 }
684