xref: /netbsd-src/usr.bin/printf/printf.c (revision 21e37cc72a480a47828990a439cde7ac9ffaf0c6)
1 /*	$NetBSD: printf.c,v 1.29 2003/08/07 11:15:33 agc 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\n\
36 	The Regents of the University of California.  All rights reserved.\n");
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 1.29 2003/08/07 11:15:33 agc 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 int	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 			(void)printf(f, fieldwidth, precision, func); \
102 		else \
103 			(void)printf(f, fieldwidth, func); \
104 	} else if (precision != -1) \
105 		(void)printf(f, precision, func); \
106 	else \
107 		(void)printf(f, func); \
108 }
109 
110 #define APF(cpp, f, func) { \
111 	if (fieldwidth != -1) { \
112 		if (precision != -1) \
113 			(void)asprintf(cpp, f, fieldwidth, precision, func); \
114 		else \
115 			(void)asprintf(cpp, f, fieldwidth, func); \
116 	} else if (precision != -1) \
117 		(void)asprintf(cpp, f, precision, func); \
118 	else \
119 		(void)asprintf(cpp, f, func); \
120 }
121 
122 int main(int, char **);
123 int main(int argc, char *argv[])
124 {
125 	char *fmt, *start;
126 	int fieldwidth, precision;
127 	char nextch;
128 	char *format;
129 	int ch;
130 
131 #if !defined(SHELL) && !defined(BUILTIN)
132 	(void)setlocale (LC_ALL, "");
133 #endif
134 
135 	while ((ch = getopt(argc, argv, "")) != -1) {
136 		switch (ch) {
137 		case '?':
138 		default:
139 			usage();
140 			return (1);
141 		}
142 	}
143 	argc -= optind;
144 	argv += optind;
145 
146 	if (argc < 1) {
147 		usage();
148 		return (1);
149 	}
150 
151 	format = *argv;
152 	gargv = ++argv;
153 
154 #define SKIP1	"#-+ 0"
155 #define SKIP2	"*0123456789"
156 	do {
157 		/*
158 		 * Basic algorithm is to scan the format string for conversion
159 		 * specifications -- once one is found, find out if the field
160 		 * width or precision is a '*'; if it is, gather up value.
161 		 * Note, format strings are reused as necessary to use up the
162 		 * provided arguments, arguments of zero/null string are
163 		 * provided to use up the format string.
164 		 */
165 
166 		/* find next format specification */
167 		for (fmt = format; (ch = *fmt++) ;) {
168 			if (ch == '\\') {
169 				char c_ch;
170 				fmt = conv_escape(fmt, &c_ch);
171 				putchar(c_ch);
172 				continue;
173 			}
174 			if (ch != '%' || (*fmt == '%' && ++fmt)) {
175 				(void)putchar(ch);
176 				continue;
177 			}
178 
179 			/* Ok - we've found a format specification,
180 			   Save its address for a later printf(). */
181 			start = fmt - 1;
182 
183 			/* skip to field width */
184 			fmt += strspn(fmt, SKIP1);
185 			fieldwidth = *fmt == '*' ? getwidth() : -1;
186 
187 			/* skip to possible '.', get following precision */
188 			fmt += strspn(fmt, SKIP2);
189 			if (*fmt == '.')
190 				++fmt;
191 			precision = *fmt == '*' ? getwidth() : -1;
192 
193 			fmt += strspn(fmt, SKIP2);
194 
195 			ch = *fmt;
196 			if (!ch) {
197 				warnx("missing format character");
198 				return (1);
199 			}
200 			/* null terminate format string to we can use it
201 			   as an argument to printf. */
202 			nextch = fmt[1];
203 			fmt[1] = 0;
204 			switch (ch) {
205 
206 			case 'B': {
207 				const char *p = conv_expand(getstr());
208 				*fmt = 's';
209 				PF(start, p);
210 				break;
211 			}
212 			case 'b': {
213 				/* There has to be a better way to do this,
214 				 * but the string we generate might have
215 				 * embedded nulls. */
216 				static char *a, *t;
217 				char *cp = getstr();
218 				/* Free on entry in case shell longjumped out */
219 				if (a != NULL)
220 					free(a);
221 				a = NULL;
222 				if (t != NULL)
223 					free(t);
224 				t = NULL;
225 				/* Count number of bytes we want to output */
226 				b_length = 0;
227 				conv_escape_str(cp, b_count);
228 				t = malloc(b_length + 1);
229 				if (t == NULL)
230 					break;
231 				memset(t, 'x', b_length);
232 				t[b_length] = 0;
233 				/* Get printf to calculate the lengths */
234 				*fmt = 's';
235 				APF(&a, start, t);
236 				b_fmt = a;
237 				/* Output leading spaces and data bytes */
238 				conv_escape_str(cp, b_output);
239 				/* Add any trailing spaces */
240 				printf("%s", b_fmt);
241 				break;
242 			}
243 			case 'c': {
244 				char p = getchr();
245 				PF(start, p);
246 				break;
247 			}
248 			case 's': {
249 				char *p = getstr();
250 				PF(start, p);
251 				break;
252 			}
253 			case 'd':
254 			case 'i': {
255 				intmax_t p = getintmax();
256 				char *f = mklong(start, ch);
257 				PF(f, p);
258 				break;
259 			}
260 			case 'o':
261 			case 'u':
262 			case 'x':
263 			case 'X': {
264 				uintmax_t p = getuintmax();
265 				char *f = mklong(start, ch);
266 				PF(f, p);
267 				break;
268 			}
269 			case 'e':
270 			case 'E':
271 			case 'f':
272 			case 'g':
273 			case 'G': {
274 				double p = getdouble();
275 				PF(start, p);
276 				break;
277 			}
278 			default:
279 				warnx("%s: invalid directive", start);
280 				return (1);
281 			}
282 			*fmt++ = ch;
283 			*fmt = nextch;
284 			/* escape if a \c was encountered */
285 			if (rval & 0x100)
286 				return (rval & ~0x100);
287 		}
288 	} while (gargv != argv && *gargv);
289 
290 	return (rval);
291 }
292 
293 /* helper functions for conv_escape_str */
294 
295 static void
296 b_count(int ch)
297 {
298 	b_length++;
299 }
300 
301 /* Output one converted character for every 'x' in the 'format' */
302 
303 static void
304 b_output(int ch)
305 {
306 	for (;;) {
307 		switch (*b_fmt++) {
308 		case 0:
309 			b_fmt--;
310 			return;
311 		case ' ':
312 			putchar(' ');
313 			break;
314 		default:
315 			putchar(ch);
316 			return;
317 		}
318 	}
319 }
320 
321 
322 /*
323  * Print SysV echo(1) style escape string
324  *	Halts processing string if a \c escape is encountered.
325  */
326 static void
327 conv_escape_str(char *str, void (*do_putchar)(int))
328 {
329 	int value;
330 	int ch;
331 	char c;
332 
333 	while ((ch = *str++)) {
334 		if (ch != '\\') {
335 			do_putchar(ch);
336 			continue;
337 		}
338 
339 		ch = *str++;
340 		if (ch == 'c') {
341 			/* \c as in SYSV echo - abort all processing.... */
342 			rval |= 0x100;
343 			break;
344 		}
345 
346 		/*
347 		 * %b string octal constants are not like those in C.
348 		 * They start with a \0, and are followed by 0, 1, 2,
349 		 * or 3 octal digits.
350 		 */
351 		if (ch == '0') {
352 			char octnum[4], *oct_end;
353 			octnum[0] = str[0];
354 			octnum[1] = str[1];
355 			octnum[2] = str[2];
356 			octnum[3] = 0;
357 			do_putchar(strtoul(octnum, &oct_end, 8));
358 			str += oct_end - octnum;
359 			continue;
360 		}
361 
362 		/* \[M][^|-]C as defined by vis(3) */
363 		if (ch == 'M' && *str == '-') {
364 			do_putchar(0200 | str[1]);
365 			str += 2;
366 			continue;
367 		}
368 		if (ch == 'M' && *str == '^') {
369 			str++;
370 			value = 0200;
371 			ch = '^';
372 		} else
373 			value = 0;
374 		if (ch == '^') {
375 			ch = *str++;
376 			if (ch == '?')
377 				value |= 0177;
378 			else
379 				value |= ch & 037;
380 			do_putchar(value);
381 			continue;
382 		}
383 
384 		/* Finally test for sequences valid in the format string */
385 		str = conv_escape(str - 1, &c);
386 		do_putchar(c);
387 	}
388 }
389 
390 /*
391  * Print "standard" escape characters
392  */
393 static char *
394 conv_escape(char *str, char *conv_ch)
395 {
396 	int value;
397 	int ch;
398 	char num_buf[4], *num_end;
399 
400 	ch = *str++;
401 
402 	switch (ch) {
403 	case '0': case '1': case '2': case '3':
404 	case '4': case '5': case '6': case '7':
405 		num_buf[0] = ch;
406 		ch = str[0];
407 		num_buf[1] = ch;
408 		num_buf[2] = ch ? str[1] : 0;
409 		num_buf[3] = 0;
410 		value = strtoul(num_buf, &num_end, 8);
411 		str += num_end  - (num_buf + 1);
412 		break;
413 
414 	case 'x':
415 		/* Hexadecimal character constants are not required to be
416 		   supported (by SuS v1) because there is no consistent
417 		   way to detect the end of the constant.
418 		   Supporting 2 byte constants is a compromise. */
419 		ch = str[0];
420 		num_buf[0] = ch;
421 		num_buf[1] = ch ? str[1] : 0;
422 		num_buf[2] = 0;
423 		value = strtoul(num_buf, &num_end, 16);
424 		str += num_end - num_buf;
425 		break;
426 
427 	case '\\':	value = '\\';	break;	/* backslash */
428 	case '\'':	value = '\'';	break;	/* single quote */
429 	case '"':	value = '"';	break;	/* double quote */
430 	case 'a':	value = '\a';	break;	/* alert */
431 	case 'b':	value = '\b';	break;	/* backspace */
432 	case 'e':	value = ESCAPE;	break;	/* escape */
433 	case 'f':	value = '\f';	break;	/* form-feed */
434 	case 'n':	value = '\n';	break;	/* newline */
435 	case 'r':	value = '\r';	break;	/* carriage-return */
436 	case 't':	value = '\t';	break;	/* tab */
437 	case 'v':	value = '\v';	break;	/* vertical-tab */
438 
439 	default:
440 		warnx("unknown escape sequence `\\%c'", ch);
441 		rval = 1;
442 		value = ch;
443 		break;
444 	}
445 
446 	*conv_ch = value;
447 	return str;
448 }
449 
450 /* expand a string so that everything is printable */
451 
452 static char *
453 conv_expand(const char *str)
454 {
455 	static char *conv_str;
456 	char *cp;
457 	int ch;
458 
459 	if (conv_str)
460 		free(conv_str);
461 	/* get a buffer that is definitely large enough.... */
462 	conv_str = malloc(4 * strlen(str) + 1);
463 	if (!conv_str)
464 		return "<no memory>";
465 	cp = conv_str;
466 
467 	while ((ch = *(unsigned char *)str++)) {
468 		switch (ch) {
469 		/* Use C escapes for expected control characters */
470 		case '\\':	ch = '\\';	break;	/* backslash */
471 		case '\'':	ch = '\'';	break;	/* single quote */
472 		case '"':	ch = '"';	break;	/* double quote */
473 		case '\a':	ch = 'a';	break;	/* alert */
474 		case '\b':	ch = 'b';	break;	/* backspace */
475 		case ESCAPE:	ch = 'e';	break;	/* escape */
476 		case '\f':	ch = 'f';	break;	/* form-feed */
477 		case '\n':	ch = 'n';	break;	/* newline */
478 		case '\r':	ch = 'r';	break;	/* carriage-return */
479 		case '\t':	ch = 't';	break;	/* tab */
480 		case '\v':	ch = 'v';	break;	/* vertical-tab */
481 		default:
482 			/* Copy anything printable */
483 			if (isprint(ch)) {
484 				*cp++ = ch;
485 				continue;
486 			}
487 			/* Use vis(3) encodings for the rest */
488 			*cp++ = '\\';
489 			if (ch & 0200) {
490 				*cp++ = 'M';
491 				ch &= ~0200;
492 			}
493 			if (ch == 0177) {
494 				*cp++ = '^';
495 				*cp++ = '?';
496 				continue;
497 			}
498 			if (ch < 040) {
499 				*cp++ = '^';
500 				*cp++ = ch | 0100;
501 				continue;
502 			}
503 			*cp++ = '-';
504 			*cp++ = ch;
505 			continue;
506 		}
507 		*cp++ = '\\';
508 		*cp++ = ch;
509 	}
510 
511 	*cp = 0;
512 	return conv_str;
513 }
514 
515 static char *
516 mklong(const char *str, int ch)
517 {
518 	static char copy[64];
519 	size_t len;
520 
521 	len = strlen(str) + 2;
522 	if (len > sizeof copy) {
523 		warnx("format %s too complex\n", str);
524 		len = 4;
525 	}
526 	(void)memmove(copy, str, len - 3);
527 	copy[len - 3] = 'j';
528 	copy[len - 2] = ch;
529 	copy[len - 1] = '\0';
530 	return (copy);
531 }
532 
533 static int
534 getchr(void)
535 {
536 	if (!*gargv)
537 		return ('\0');
538 	return ((int)**gargv++);
539 }
540 
541 static char *
542 getstr(void)
543 {
544 	if (!*gargv)
545 		return ("");
546 	return (*gargv++);
547 }
548 
549 static int
550 getwidth(void)
551 {
552 	long val;
553 	char *s, *ep;
554 
555 	s = *gargv;
556 	if (!*gargv)
557 		return (0);
558 	gargv++;
559 
560 	errno = 0;
561 	val = strtoul(s, &ep, 0);
562 	check_conversion(s, ep);
563 
564 	/* Arbitrarily 'restrict' field widths to 1Mbyte */
565 	if (val < 0 || val > 1 << 20) {
566 		warnx("%s: invalid field width", s);
567 		return 0;
568 	}
569 
570 	return val;
571 }
572 
573 static intmax_t
574 getintmax(void)
575 {
576 	intmax_t val;
577 	char *cp, *ep;
578 
579 	cp = *gargv;
580 	if (cp == NULL)
581 		return 0;
582 	gargv++;
583 
584 	if (*cp == '\"' || *cp == '\'')
585 		return *(cp+1);
586 
587 	errno = 0;
588 	val = strtoimax(cp, &ep, 0);
589 	check_conversion(cp, ep);
590 	return val;
591 }
592 
593 static uintmax_t
594 getuintmax(void)
595 {
596 	uintmax_t val;
597 	char *cp, *ep;
598 
599 	cp = *gargv;
600 	if (cp == NULL)
601 		return 0;
602 	gargv++;
603 
604 	if (*cp == '\"' || *cp == '\'')
605 		return *(cp+1);
606 
607 	/* strtoumax won't error -ve values */
608 	while (isspace(*(unsigned char *)cp))
609 		cp++;
610 	if (*cp == '-') {
611 		warnx("%s: expected positive numeric value", cp);
612 		rval = 1;
613 		return 0;
614 	}
615 
616 	errno = 0;
617 	val = strtoumax(cp, &ep, 0);
618 	check_conversion(cp, ep);
619 	return val;
620 }
621 
622 static double
623 getdouble(void)
624 {
625 	double val;
626 	char *ep;
627 
628 	if (!*gargv)
629 		return (0.0);
630 
631 	if (**gargv == '\"' || **gargv == '\'')
632 		return (double) *((*gargv++)+1);
633 
634 	errno = 0;
635 	val = strtod(*gargv, &ep);
636 	check_conversion(*gargv++, ep);
637 	return val;
638 }
639 
640 static void
641 check_conversion(const char *s, const char *ep)
642 {
643 	if (*ep) {
644 		if (ep == s)
645 			warnx("%s: expected numeric value", s);
646 		else
647 			warnx("%s: not completely converted", s);
648 		rval = 1;
649 	} else if (errno == ERANGE) {
650 		warnx("%s: %s", s, strerror(ERANGE));
651 		rval = 1;
652 	}
653 }
654 
655 static void
656 usage(void)
657 {
658 	(void)fprintf(stderr, "usage: printf format [arg ...]\n");
659 }
660