xref: /netbsd-src/usr.bin/printf/printf.c (revision d710132b4b8ce7f7cccaaf660cb16aa16b4077a0)
1 /*	$NetBSD: printf.c,v 1.27 2003/06/25 09:54:15 dsl 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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #ifndef lint
38 #if !defined(BUILTIN) && !defined(SHELL)
39 __COPYRIGHT("@(#) Copyright (c) 1989, 1993\n\
40 	The Regents of the University of California.  All rights reserved.\n");
41 #endif
42 #endif
43 
44 #ifndef lint
45 #if 0
46 static char sccsid[] = "@(#)printf.c	8.2 (Berkeley) 3/22/95";
47 #else
48 __RCSID("$NetBSD: printf.c,v 1.27 2003/06/25 09:54:15 dsl Exp $");
49 #endif
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 <stdarg.h>
61 #include <stdio.h>
62 #include <stdlib.h>
63 #include <string.h>
64 #include <unistd.h>
65 
66 #ifdef __GNUC__
67 #define ESCAPE '\e'
68 #else
69 #define ESCAPE 033
70 #endif
71 
72 static void	 conv_escape_str(char *, void (*)(int));
73 static char	*conv_escape(char *, char *);
74 static char	*conv_expand(const char *);
75 static int	 getchr(void);
76 static double	 getdouble(void);
77 static int	 getwidth(void);
78 static intmax_t	 getintmax(void);
79 static uintmax_t getuintmax(void);
80 static char	*getstr(void);
81 static char	*mklong(const char *, int);
82 static void      check_conversion(const char *, const char *);
83 static void	 usage(void);
84 
85 static void	b_count(int);
86 static void	b_output(int);
87 static int	b_length;
88 static char	*b_fmt;
89 
90 static int	rval;
91 static char  **gargv;
92 
93 #ifdef BUILTIN		/* csh builtin */
94 #define main progprintf
95 #endif
96 
97 #ifdef SHELL		/* sh (aka ash) builtin */
98 #define main printfcmd
99 #include "../../bin/sh/bltin/bltin.h"
100 #endif /* SHELL */
101 
102 #define PF(f, func) { \
103 	if (fieldwidth != -1) { \
104 		if (precision != -1) \
105 			(void)printf(f, fieldwidth, precision, func); \
106 		else \
107 			(void)printf(f, fieldwidth, func); \
108 	} else if (precision != -1) \
109 		(void)printf(f, precision, func); \
110 	else \
111 		(void)printf(f, func); \
112 }
113 
114 #define APF(cpp, f, func) { \
115 	if (fieldwidth != -1) { \
116 		if (precision != -1) \
117 			(void)asprintf(cpp, f, fieldwidth, precision, func); \
118 		else \
119 			(void)asprintf(cpp, f, fieldwidth, func); \
120 	} else if (precision != -1) \
121 		(void)asprintf(cpp, f, precision, func); \
122 	else \
123 		(void)asprintf(cpp, f, func); \
124 }
125 
126 int main(int, char **);
127 int main(int argc, char *argv[])
128 {
129 	char *fmt, *start;
130 	int fieldwidth, precision;
131 	char nextch;
132 	char *format;
133 	int ch;
134 
135 #if !defined(SHELL) && !defined(BUILTIN)
136 	(void)setlocale (LC_ALL, "");
137 #endif
138 
139 /*
140  * IEEE 1003.1 (2003) doesn't say that printf(1) should conform to the
141  * "Utility Syntax Guidlines".
142  * It just says: Options: None.
143  */
144 #if 0
145 	while ((ch = getopt(argc, argv, "")) != -1) {
146 		switch (ch) {
147 		case '?':
148 		default:
149 			usage();
150 			return (1);
151 		}
152 	}
153 	argc -= optind;
154 	argv += optind;
155 #endif
156 
157 	if (argc < 1) {
158 		usage();
159 		return (1);
160 	}
161 
162 	format = *argv;
163 	gargv = ++argv;
164 
165 #define SKIP1	"#-+ 0"
166 #define SKIP2	"*0123456789"
167 	do {
168 		/*
169 		 * Basic algorithm is to scan the format string for conversion
170 		 * specifications -- once one is found, find out if the field
171 		 * width or precision is a '*'; if it is, gather up value.
172 		 * Note, format strings are reused as necessary to use up the
173 		 * provided arguments, arguments of zero/null string are
174 		 * provided to use up the format string.
175 		 */
176 
177 		/* find next format specification */
178 		for (fmt = format; (ch = *fmt++) ;) {
179 			if (ch == '\\') {
180 				char c_ch;
181 				fmt = conv_escape(fmt, &c_ch);
182 				putchar(c_ch);
183 				continue;
184 			}
185 			if (ch != '%' || (*fmt == '%' && ++fmt)) {
186 				(void)putchar(ch);
187 				continue;
188 			}
189 
190 			/* Ok - we've found a format specification,
191 			   Save its address for a later printf(). */
192 			start = fmt - 1;
193 
194 			/* skip to field width */
195 			fmt += strspn(fmt, SKIP1);
196 			fieldwidth = *fmt == '*' ? getwidth() : -1;
197 
198 			/* skip to possible '.', get following precision */
199 			fmt += strspn(fmt, SKIP2);
200 			if (*fmt == '.')
201 				++fmt;
202 			precision = *fmt == '*' ? getwidth() : -1;
203 
204 			fmt += strspn(fmt, SKIP2);
205 
206 			ch = *fmt;
207 			if (!ch) {
208 				warnx("missing format character");
209 				return (1);
210 			}
211 			/* null terminate format string to we can use it
212 			   as an argument to printf. */
213 			nextch = fmt[1];
214 			fmt[1] = 0;
215 			switch (ch) {
216 
217 			case 'B': {
218 				const char *p = conv_expand(getstr());
219 				*fmt = 's';
220 				PF(start, p);
221 				break;
222 			}
223 			case 'b': {
224 				/* There has to be a better way to do this,
225 				 * but the string we generate might have
226 				 * embedded nulls. */
227 				static char *a, *t;
228 				char *cp = getstr();
229 				/* Free on entry in case shell longjumped out */
230 				if (a != NULL)
231 					free(a);
232 				a = NULL;
233 				if (t != NULL)
234 					free(t);
235 				t = NULL;
236 				/* Count number of bytes we want to output */
237 				b_length = 0;
238 				conv_escape_str(cp, b_count);
239 				t = malloc(b_length + 1);
240 				if (t == NULL)
241 					break;
242 				memset(t, 'x', b_length);
243 				t[b_length] = 0;
244 				/* Get printf to calculate the lengths */
245 				*fmt = 's';
246 				APF(&a, start, t);
247 				b_fmt = a;
248 				/* Output leading spaces and data bytes */
249 				conv_escape_str(cp, b_output);
250 				/* Add any trailing spaces */
251 				printf("%s", b_fmt);
252 				break;
253 			}
254 			case 'c': {
255 				char p = getchr();
256 				PF(start, p);
257 				break;
258 			}
259 			case 's': {
260 				char *p = getstr();
261 				PF(start, p);
262 				break;
263 			}
264 			case 'd':
265 			case 'i': {
266 				intmax_t p = getintmax();
267 				char *f = mklong(start, ch);
268 				PF(f, p);
269 				break;
270 			}
271 			case 'o':
272 			case 'u':
273 			case 'x':
274 			case 'X': {
275 				uintmax_t p = getuintmax();
276 				char *f = mklong(start, ch);
277 				PF(f, p);
278 				break;
279 			}
280 			case 'e':
281 			case 'E':
282 			case 'f':
283 			case 'g':
284 			case 'G': {
285 				double p = getdouble();
286 				PF(start, p);
287 				break;
288 			}
289 			default:
290 				warnx("%s: invalid directive", start);
291 				return (1);
292 			}
293 			*fmt++ = ch;
294 			*fmt = nextch;
295 			/* escape if a \c was encountered */
296 			if (rval & 0x100)
297 				return (rval & ~0x100);
298 		}
299 	} while (gargv != argv && *gargv);
300 
301 	return (rval);
302 }
303 
304 /* helper functions for conv_escape_str */
305 
306 static void
307 b_count(int ch)
308 {
309 	b_length++;
310 }
311 
312 /* Output one converted character for every 'x' in the 'format' */
313 
314 static void
315 b_output(int ch)
316 {
317 	for (;;) {
318 		switch (*b_fmt++) {
319 		case 0:
320 			b_fmt--;
321 			return;
322 		case ' ':
323 			putchar(' ');
324 			break;
325 		default:
326 			putchar(ch);
327 			return;
328 		}
329 	}
330 }
331 
332 
333 /*
334  * Print SysV echo(1) style escape string
335  *	Halts processing string if a \c escape is encountered.
336  */
337 static void
338 conv_escape_str(char *str, void (*do_putchar)(int))
339 {
340 	int value;
341 	int ch;
342 	char c;
343 
344 	while ((ch = *str++)) {
345 		if (ch != '\\') {
346 			do_putchar(ch);
347 			continue;
348 		}
349 
350 		ch = *str++;
351 		if (ch == 'c') {
352 			/* \c as in SYSV echo - abort all processing.... */
353 			rval |= 0x100;
354 			break;
355 		}
356 
357 		/*
358 		 * %b string octal constants are not like those in C.
359 		 * They start with a \0, and are followed by 0, 1, 2,
360 		 * or 3 octal digits.
361 		 */
362 		if (ch == '0') {
363 			char octnum[4], *oct_end;
364 			octnum[0] = str[0];
365 			octnum[1] = str[1];
366 			octnum[2] = str[2];
367 			octnum[3] = 0;
368 			do_putchar(strtoul(octnum, &oct_end, 8));
369 			str += oct_end - octnum;
370 			continue;
371 		}
372 
373 		/* \[M][^|-]C as defined by vis(3) */
374 		if (ch == 'M' && *str == '-') {
375 			do_putchar(0200 | str[1]);
376 			str += 2;
377 			continue;
378 		}
379 		if (ch == 'M' && *str == '^') {
380 			str++;
381 			value = 0200;
382 			ch = '^';
383 		} else
384 			value = 0;
385 		if (ch == '^') {
386 			ch = *str++;
387 			if (ch == '?')
388 				value |= 0177;
389 			else
390 				value |= ch & 037;
391 			do_putchar(value);
392 			continue;
393 		}
394 
395 		/* Finally test for sequences valid in the format string */
396 		str = conv_escape(str - 1, &c);
397 		do_putchar(c);
398 	}
399 }
400 
401 /*
402  * Print "standard" escape characters
403  */
404 static char *
405 conv_escape(char *str, char *conv_ch)
406 {
407 	int value;
408 	int ch;
409 	char num_buf[4], *num_end;
410 
411 	ch = *str++;
412 
413 	switch (ch) {
414 	case '0': case '1': case '2': case '3':
415 	case '4': case '5': case '6': case '7':
416 		num_buf[0] = ch;
417 		ch = str[0];
418 		num_buf[1] = ch;
419 		num_buf[2] = ch ? str[1] : 0;
420 		num_buf[3] = 0;
421 		value = strtoul(num_buf, &num_end, 8);
422 		str += num_end  - (num_buf + 1);
423 		break;
424 
425 	case 'x':
426 		/* Hexadecimal character constants are not required to be
427 		   supported (by SuS v1) because there is no consistent
428 		   way to detect the end of the constant.
429 		   Supporting 2 byte constants is a compromise. */
430 		ch = str[0];
431 		num_buf[0] = ch;
432 		num_buf[1] = ch ? str[1] : 0;
433 		num_buf[2] = 0;
434 		value = strtoul(num_buf, &num_end, 16);
435 		str += num_end - num_buf;
436 		break;
437 
438 	case '\\':	value = '\\';	break;	/* backslash */
439 	case '\'':	value = '\'';	break;	/* single quote */
440 	case '"':	value = '"';	break;	/* double quote */
441 	case 'a':	value = '\a';	break;	/* alert */
442 	case 'b':	value = '\b';	break;	/* backspace */
443 	case 'e':	value = ESCAPE;	break;	/* escape */
444 	case 'f':	value = '\f';	break;	/* form-feed */
445 	case 'n':	value = '\n';	break;	/* newline */
446 	case 'r':	value = '\r';	break;	/* carriage-return */
447 	case 't':	value = '\t';	break;	/* tab */
448 	case 'v':	value = '\v';	break;	/* vertical-tab */
449 
450 	default:
451 		warnx("unknown escape sequence `\\%c'", ch);
452 		rval = 1;
453 		value = ch;
454 		break;
455 	}
456 
457 	*conv_ch = value;
458 	return str;
459 }
460 
461 /* expand a string so that everything is printable */
462 
463 static char *
464 conv_expand(const char *str)
465 {
466 	static char *conv_str;
467 	char *cp;
468 	int ch;
469 
470 	if (conv_str)
471 		free(conv_str);
472 	/* get a buffer that is definitely large enough.... */
473 	conv_str = malloc(4 * strlen(str) + 1);
474 	if (!conv_str)
475 		return "<no memory>";
476 	cp = conv_str;
477 
478 	while ((ch = *(unsigned char *)str++)) {
479 		switch (ch) {
480 		/* Use C escapes for expected control characters */
481 		case '\\':	ch = '\\';	break;	/* backslash */
482 		case '\'':	ch = '\'';	break;	/* single quote */
483 		case '"':	ch = '"';	break;	/* double quote */
484 		case '\a':	ch = 'a';	break;	/* alert */
485 		case '\b':	ch = 'b';	break;	/* backspace */
486 		case ESCAPE:	ch = 'e';	break;	/* escape */
487 		case '\f':	ch = 'f';	break;	/* form-feed */
488 		case '\n':	ch = 'n';	break;	/* newline */
489 		case '\r':	ch = 'r';	break;	/* carriage-return */
490 		case '\t':	ch = 't';	break;	/* tab */
491 		case '\v':	ch = 'v';	break;	/* vertical-tab */
492 		default:
493 			/* Copy anything printable */
494 			if (isprint(ch)) {
495 				*cp++ = ch;
496 				continue;
497 			}
498 			/* Use vis(3) encodings for the rest */
499 			*cp++ = '\\';
500 			if (ch & 0200) {
501 				*cp++ = 'M';
502 				ch &= ~0200;
503 			}
504 			if (ch == 0177) {
505 				*cp++ = '^';
506 				*cp++ = '?';
507 				continue;
508 			}
509 			if (ch < 040) {
510 				*cp++ = '^';
511 				*cp++ = ch | 0100;
512 				continue;
513 			}
514 			*cp++ = '-';
515 			*cp++ = ch;
516 			continue;
517 		}
518 		*cp++ = '\\';
519 		*cp++ = ch;
520 	}
521 
522 	*cp = 0;
523 	return conv_str;
524 }
525 
526 static char *
527 mklong(const char *str, int ch)
528 {
529 	static char copy[64];
530 	size_t len;
531 
532 	len = strlen(str) + 2;
533 	if (len > sizeof copy) {
534 		warnx("format %s too complex\n", str);
535 		len = 4;
536 	}
537 	(void)memmove(copy, str, len - 3);
538 	copy[len - 3] = 'j';
539 	copy[len - 2] = ch;
540 	copy[len - 1] = '\0';
541 	return (copy);
542 }
543 
544 static int
545 getchr(void)
546 {
547 	if (!*gargv)
548 		return ('\0');
549 	return ((int)**gargv++);
550 }
551 
552 static char *
553 getstr(void)
554 {
555 	if (!*gargv)
556 		return ("");
557 	return (*gargv++);
558 }
559 
560 static int
561 getwidth(void)
562 {
563 	long val;
564 	char *s, *ep;
565 
566 	s = *gargv;
567 	if (!*gargv)
568 		return (0);
569 	gargv++;
570 
571 	errno = 0;
572 	val = strtoul(s, &ep, 0);
573 	check_conversion(s, ep);
574 
575 	/* Arbitrarily 'restrict' field widths to 1Mbyte */
576 	if (val < 0 || val > 1 << 20) {
577 		warnx("%s: invalid field width", s);
578 		return 0;
579 	}
580 
581 	return val;
582 }
583 
584 static intmax_t
585 getintmax(void)
586 {
587 	intmax_t val;
588 	char *cp, *ep;
589 
590 	cp = *gargv;
591 	if (cp == NULL)
592 		return 0;
593 	gargv++;
594 
595 	if (*cp == '\"' || *cp == '\'')
596 		return *(cp+1);
597 
598 	errno = 0;
599 	val = strtoimax(cp, &ep, 0);
600 	check_conversion(cp, ep);
601 	return val;
602 }
603 
604 static uintmax_t
605 getuintmax(void)
606 {
607 	uintmax_t val;
608 	char *cp, *ep;
609 
610 	cp = *gargv;
611 	if (cp == NULL)
612 		return 0;
613 	gargv++;
614 
615 	if (*cp == '\"' || *cp == '\'')
616 		return *(cp+1);
617 
618 	/* strtoumax won't error -ve values */
619 	while (isspace(*(unsigned char *)cp))
620 		cp++;
621 	if (*cp == '-') {
622 		warnx("%s: expected positive numeric value", cp);
623 		rval = 1;
624 		return 0;
625 	}
626 
627 	errno = 0;
628 	val = strtoumax(cp, &ep, 0);
629 	check_conversion(cp, ep);
630 	return val;
631 }
632 
633 static double
634 getdouble(void)
635 {
636 	double val;
637 	char *ep;
638 
639 	if (!*gargv)
640 		return (0.0);
641 
642 	if (**gargv == '\"' || **gargv == '\'')
643 		return (double) *((*gargv++)+1);
644 
645 	errno = 0;
646 	val = strtod(*gargv, &ep);
647 	check_conversion(*gargv++, ep);
648 	return val;
649 }
650 
651 static void
652 check_conversion(const char *s, const char *ep)
653 {
654 	if (*ep) {
655 		if (ep == s)
656 			warnx("%s: expected numeric value", s);
657 		else
658 			warnx("%s: not completely converted", s);
659 		rval = 1;
660 	} else if (errno == ERANGE) {
661 		warnx("%s: %s", s, strerror(ERANGE));
662 		rval = 1;
663 	}
664 }
665 
666 static void
667 usage(void)
668 {
669 	(void)fprintf(stderr, "usage: printf format [arg ...]\n");
670 }
671