xref: /freebsd/usr.bin/printf/printf.c (revision b1866dfea3f3f142697f8e325db49b8e668fba35)
1 /*-
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 /*
30  * Important: This file is used both as a standalone program /usr/bin/printf
31  * and as a builtin for /bin/sh (#define SHELL).
32  */
33 
34 #ifndef SHELL
35 #ifndef lint
36 static char const copyright[] =
37 "@(#) Copyright (c) 1989, 1993\n\
38 	The Regents of the University of California.  All rights reserved.\n";
39 #endif /* not lint */
40 #endif
41 
42 #ifndef lint
43 #if 0
44 static char const sccsid[] = "@(#)printf.c	8.1 (Berkeley) 7/20/93";
45 #endif
46 static const char rcsid[] =
47   "$FreeBSD$";
48 #endif /* not lint */
49 
50 #include <sys/types.h>
51 
52 #include <err.h>
53 #include <errno.h>
54 #include <inttypes.h>
55 #include <limits.h>
56 #include <locale.h>
57 #include <stdio.h>
58 #include <stdlib.h>
59 #include <string.h>
60 #include <unistd.h>
61 #include <wchar.h>
62 
63 #ifdef SHELL
64 #define main printfcmd
65 #include "bltin/bltin.h"
66 #include "error.h"
67 #endif
68 
69 #define PF(f, func) do {						\
70 	char *b = NULL;							\
71 	if (havewidth)							\
72 		if (haveprec)						\
73 			(void)asprintf(&b, f, fieldwidth, precision, func); \
74 		else							\
75 			(void)asprintf(&b, f, fieldwidth, func);	\
76 	else if (haveprec)						\
77 		(void)asprintf(&b, f, precision, func);			\
78 	else								\
79 		(void)asprintf(&b, f, func);				\
80 	if (b) {							\
81 		(void)fputs(b, stdout);					\
82 		free(b);						\
83 	}								\
84 } while (0)
85 
86 static int	 asciicode(void);
87 static char	*printf_doformat(char *, int *);
88 static int	 escape(char *, int, size_t *);
89 static int	 getchr(void);
90 static int	 getfloating(long double *, int);
91 static int	 getint(int *);
92 static int	 getnum(intmax_t *, uintmax_t *, int);
93 static const char
94 		*getstr(void);
95 static char	*mknum(char *, char);
96 static void	 usage(void);
97 
98 static char **gargv;
99 
100 int
101 main(int argc, char *argv[])
102 {
103 	size_t len;
104 	int ch, chopped, end, rval;
105 	char *format, *fmt, *start;
106 
107 #ifndef SHELL
108 	(void) setlocale(LC_ALL, "");
109 #endif
110 #ifdef SHELL
111 	optreset = 1; optind = 1; opterr = 0; /* initialize getopt */
112 #endif
113 	while ((ch = getopt(argc, argv, "")) != -1)
114 		switch (ch) {
115 		case '?':
116 		default:
117 			usage();
118 			return (1);
119 		}
120 	argc -= optind;
121 	argv += optind;
122 
123 	if (argc < 1) {
124 		usage();
125 		return (1);
126 	}
127 
128 #ifdef SHELL
129 	INTOFF;
130 #endif
131 	/*
132 	 * Basic algorithm is to scan the format string for conversion
133 	 * specifications -- once one is found, find out if the field
134 	 * width or precision is a '*'; if it is, gather up value.  Note,
135 	 * format strings are reused as necessary to use up the provided
136 	 * arguments, arguments of zero/null string are provided to use
137 	 * up the format string.
138 	 */
139 	fmt = format = *argv;
140 	chopped = escape(fmt, 1, &len);		/* backslash interpretation */
141 	rval = end = 0;
142 	gargv = ++argv;
143 	for (;;) {
144 		start = fmt;
145 		while (fmt < format + len) {
146 			if (fmt[0] == '%') {
147 				fwrite(start, 1, fmt - start, stdout);
148 				if (fmt[1] == '%') {
149 					/* %% prints a % */
150 					putchar('%');
151 					fmt += 2;
152 				} else {
153 					fmt = printf_doformat(fmt, &rval);
154 					if (fmt == NULL) {
155 #ifdef SHELL
156 						INTON;
157 #endif
158 						return (1);
159 					}
160 					end = 0;
161 				}
162 				start = fmt;
163 			} else
164 				fmt++;
165 		}
166 
167 		if (end == 1) {
168 			warnx("missing format character");
169 #ifdef SHELL
170 			INTON;
171 #endif
172 			return (1);
173 		}
174 		fwrite(start, 1, fmt - start, stdout);
175 		if (chopped || !*gargv) {
176 #ifdef SHELL
177 			INTON;
178 #endif
179 			return (rval);
180 		}
181 		/* Restart at the beginning of the format string. */
182 		fmt = format;
183 		end = 1;
184 	}
185 	/* NOTREACHED */
186 }
187 
188 
189 static char *
190 printf_doformat(char *start, int *rval)
191 {
192 	static const char skip1[] = "#'-+ 0";
193 	static const char skip2[] = "0123456789";
194 	char *fmt;
195 	int fieldwidth, haveprec, havewidth, mod_ldbl, precision;
196 	char convch, nextch;
197 
198 	fmt = start + 1;
199 	/* skip to field width */
200 	fmt += strspn(fmt, skip1);
201 	if (*fmt == '*') {
202 		if (getint(&fieldwidth))
203 			return (NULL);
204 		havewidth = 1;
205 		++fmt;
206 	} else {
207 		havewidth = 0;
208 
209 		/* skip to possible '.', get following precision */
210 		fmt += strspn(fmt, skip2);
211 	}
212 	if (*fmt == '.') {
213 		/* precision present? */
214 		++fmt;
215 		if (*fmt == '*') {
216 			if (getint(&precision))
217 				return (NULL);
218 			haveprec = 1;
219 			++fmt;
220 		} else {
221 			haveprec = 0;
222 
223 			/* skip to conversion char */
224 			fmt += strspn(fmt, skip2);
225 		}
226 	} else
227 		haveprec = 0;
228 	if (!*fmt) {
229 		warnx("missing format character");
230 		return (NULL);
231 	}
232 
233 	/*
234 	 * Look for a length modifier.  POSIX doesn't have these, so
235 	 * we only support them for floating-point conversions, which
236 	 * are extensions.  This is useful because the L modifier can
237 	 * be used to gain extra range and precision, while omitting
238 	 * it is more likely to produce consistent results on different
239 	 * architectures.  This is not so important for integers
240 	 * because overflow is the only bad thing that can happen to
241 	 * them, but consider the command  printf %a 1.1
242 	 */
243 	if (*fmt == 'L') {
244 		mod_ldbl = 1;
245 		fmt++;
246 		if (!strchr("aAeEfFgG", *fmt)) {
247 			warnx("bad modifier L for %%%c", *fmt);
248 			return (NULL);
249 		}
250 	} else {
251 		mod_ldbl = 0;
252 	}
253 
254 	convch = *fmt;
255 	nextch = *++fmt;
256 	*fmt = '\0';
257 	switch (convch) {
258 	case 'b': {
259 		size_t len;
260 		char *p;
261 		int getout;
262 
263 		p = strdup(getstr());
264 		if (p == NULL) {
265 			warnx("%s", strerror(ENOMEM));
266 			return (NULL);
267 		}
268 		getout = escape(p, 0, &len);
269 		*(fmt - 1) = 's';
270 		PF(start, p);
271 		*(fmt - 1) = 'b';
272 		free(p);
273 		if (getout)
274 			return (fmt);
275 		break;
276 	}
277 	case 'c': {
278 		char p;
279 
280 		p = getchr();
281 		PF(start, p);
282 		break;
283 	}
284 	case 's': {
285 		const char *p;
286 
287 		p = getstr();
288 		PF(start, p);
289 		break;
290 	}
291 	case 'd': case 'i': case 'o': case 'u': case 'x': case 'X': {
292 		char *f;
293 		intmax_t val;
294 		uintmax_t uval;
295 		int signedconv;
296 
297 		signedconv = (convch == 'd' || convch == 'i');
298 		if ((f = mknum(start, convch)) == NULL)
299 			return (NULL);
300 		if (getnum(&val, &uval, signedconv))
301 			*rval = 1;
302 		if (signedconv)
303 			PF(f, val);
304 		else
305 			PF(f, uval);
306 		break;
307 	}
308 	case 'e': case 'E':
309 	case 'f': case 'F':
310 	case 'g': case 'G':
311 	case 'a': case 'A': {
312 		long double p;
313 
314 		if (getfloating(&p, mod_ldbl))
315 			*rval = 1;
316 		if (mod_ldbl)
317 			PF(start, p);
318 		else
319 			PF(start, (double)p);
320 		break;
321 	}
322 	default:
323 		warnx("illegal format character %c", convch);
324 		return (NULL);
325 	}
326 	*fmt = nextch;
327 	return (fmt);
328 }
329 
330 static char *
331 mknum(char *str, char ch)
332 {
333 	static char *copy;
334 	static size_t copy_size;
335 	char *newcopy;
336 	size_t len, newlen;
337 
338 	len = strlen(str) + 2;
339 	if (len > copy_size) {
340 		newlen = ((len + 1023) >> 10) << 10;
341 		if ((newcopy = realloc(copy, newlen)) == NULL)
342 		{
343 			warnx("%s", strerror(ENOMEM));
344 			return (NULL);
345 		}
346 		copy = newcopy;
347 		copy_size = newlen;
348 	}
349 
350 	memmove(copy, str, len - 3);
351 	copy[len - 3] = 'j';
352 	copy[len - 2] = ch;
353 	copy[len - 1] = '\0';
354 	return (copy);
355 }
356 
357 static int
358 escape(char *fmt, int percent, size_t *len)
359 {
360 	char *save, *store, c;
361 	int value;
362 
363 	for (save = store = fmt; ((c = *fmt) != 0); ++fmt, ++store) {
364 		if (c != '\\') {
365 			*store = c;
366 			continue;
367 		}
368 		switch (*++fmt) {
369 		case '\0':		/* EOS, user error */
370 			*store = '\\';
371 			*++store = '\0';
372 			*len = store - save;
373 			return (0);
374 		case '\\':		/* backslash */
375 		case '\'':		/* single quote */
376 			*store = *fmt;
377 			break;
378 		case 'a':		/* bell/alert */
379 			*store = '\a';
380 			break;
381 		case 'b':		/* backspace */
382 			*store = '\b';
383 			break;
384 		case 'c':
385 			*store = '\0';
386 			*len = store - save;
387 			return (1);
388 		case 'f':		/* form-feed */
389 			*store = '\f';
390 			break;
391 		case 'n':		/* newline */
392 			*store = '\n';
393 			break;
394 		case 'r':		/* carriage-return */
395 			*store = '\r';
396 			break;
397 		case 't':		/* horizontal tab */
398 			*store = '\t';
399 			break;
400 		case 'v':		/* vertical tab */
401 			*store = '\v';
402 			break;
403 					/* octal constant */
404 		case '0': case '1': case '2': case '3':
405 		case '4': case '5': case '6': case '7':
406 			c = (!percent && *fmt == '0') ? 4 : 3;
407 			for (value = 0;
408 			    c-- && *fmt >= '0' && *fmt <= '7'; ++fmt) {
409 				value <<= 3;
410 				value += *fmt - '0';
411 			}
412 			--fmt;
413 			if (percent && value == '%') {
414 				*store++ = '%';
415 				*store = '%';
416 			} else
417 				*store = (char)value;
418 			break;
419 		default:
420 			*store = *fmt;
421 			break;
422 		}
423 	}
424 	*store = '\0';
425 	*len = store - save;
426 	return (0);
427 }
428 
429 static int
430 getchr(void)
431 {
432 	if (!*gargv)
433 		return ('\0');
434 	return ((int)**gargv++);
435 }
436 
437 static const char *
438 getstr(void)
439 {
440 	if (!*gargv)
441 		return ("");
442 	return (*gargv++);
443 }
444 
445 static int
446 getint(int *ip)
447 {
448 	intmax_t val;
449 	uintmax_t uval;
450 	int rval;
451 
452 	if (getnum(&val, &uval, 1))
453 		return (1);
454 	rval = 0;
455 	if (val < INT_MIN || val > INT_MAX) {
456 		warnx("%s: %s", *gargv, strerror(ERANGE));
457 		rval = 1;
458 	}
459 	*ip = (int)val;
460 	return (rval);
461 }
462 
463 static int
464 getnum(intmax_t *ip, uintmax_t *uip, int signedconv)
465 {
466 	char *ep;
467 	int rval;
468 
469 	if (!*gargv) {
470 		*ip = 0;
471 		return (0);
472 	}
473 	if (**gargv == '"' || **gargv == '\'') {
474 		if (signedconv)
475 			*ip = asciicode();
476 		else
477 			*uip = asciicode();
478 		return (0);
479 	}
480 	rval = 0;
481 	errno = 0;
482 	if (signedconv)
483 		*ip = strtoimax(*gargv, &ep, 0);
484 	else
485 		*uip = strtoumax(*gargv, &ep, 0);
486 	if (ep == *gargv) {
487 		warnx("%s: expected numeric value", *gargv);
488 		rval = 1;
489 	}
490 	else if (*ep != '\0') {
491 		warnx("%s: not completely converted", *gargv);
492 		rval = 1;
493 	}
494 	if (errno == ERANGE) {
495 		warnx("%s: %s", *gargv, strerror(ERANGE));
496 		rval = 1;
497 	}
498 	++gargv;
499 	return (rval);
500 }
501 
502 static int
503 getfloating(long double *dp, int mod_ldbl)
504 {
505 	char *ep;
506 	int rval;
507 
508 	if (!*gargv) {
509 		*dp = 0.0;
510 		return (0);
511 	}
512 	if (**gargv == '"' || **gargv == '\'') {
513 		*dp = asciicode();
514 		return (0);
515 	}
516 	rval = 0;
517 	errno = 0;
518 	if (mod_ldbl)
519 		*dp = strtold(*gargv, &ep);
520 	else
521 		*dp = strtod(*gargv, &ep);
522 	if (ep == *gargv) {
523 		warnx("%s: expected numeric value", *gargv);
524 		rval = 1;
525 	} else if (*ep != '\0') {
526 		warnx("%s: not completely converted", *gargv);
527 		rval = 1;
528 	}
529 	if (errno == ERANGE) {
530 		warnx("%s: %s", *gargv, strerror(ERANGE));
531 		rval = 1;
532 	}
533 	++gargv;
534 	return (rval);
535 }
536 
537 static int
538 asciicode(void)
539 {
540 	int ch;
541 	wchar_t wch;
542 	mbstate_t mbs;
543 
544 	ch = (unsigned char)**gargv;
545 	if (ch == '\'' || ch == '"') {
546 		memset(&mbs, 0, sizeof(mbs));
547 		switch (mbrtowc(&wch, *gargv + 1, MB_LEN_MAX, &mbs)) {
548 		case (size_t)-2:
549 		case (size_t)-1:
550 			wch = (unsigned char)gargv[0][1];
551 			break;
552 		case 0:
553 			wch = 0;
554 			break;
555 		}
556 		ch = wch;
557 	}
558 	++gargv;
559 	return (ch);
560 }
561 
562 static void
563 usage(void)
564 {
565 	(void)fprintf(stderr, "usage: printf format [arguments ...]\n");
566 }
567