xref: /freebsd/usr.bin/printf/printf.c (revision 23f282aa31e9b6fceacd449020e936e98d6f2298)
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  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #if !defined(BUILTIN) && !defined(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 static char const sccsid[] = "@(#)printf.c	8.1 (Berkeley) 7/20/93";
44 static const char rcsid[] =
45   "$FreeBSD$";
46 #endif /* not lint */
47 
48 #include <sys/types.h>
49 
50 #include <err.h>
51 #include <errno.h>
52 #include <limits.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <unistd.h>
57 
58 #ifdef SHELL
59 #define main printfcmd
60 #include "bltin/bltin.h"
61 #else
62 #define	warnx1(a, b, c)		warnx(a)
63 #define	warnx2(a, b, c)		warnx(a, b)
64 #define	warnx3(a, b, c)		warnx(a, b, c)
65 #endif
66 
67 #define PF(f, func) { \
68 	char *b = NULL; \
69 	if (fieldwidth) \
70 		if (precision) \
71 			(void)asprintf(&b, f, fieldwidth, precision, func); \
72 		else \
73 			(void)asprintf(&b, f, fieldwidth, func); \
74 	else if (precision) \
75 		(void)asprintf(&b, f, precision, func); \
76 	else \
77 		(void)asprintf(&b, f, func); \
78 	if (b) { \
79 		(void)fputs(b, stdout); \
80 		free(b); \
81 	} \
82 }
83 
84 static int	 asciicode __P((void));
85 static void	 escape __P((char *));
86 static int	 getchr __P((void));
87 static double	 getdouble __P((void));
88 static int	 getint __P((int *));
89 static int	 getlong __P((long *));
90 static char	*getstr __P((void));
91 static char	*mklong __P((char *, int));
92 static void	 usage __P((void));
93 
94 static char **gargv;
95 
96 int
97 #ifdef BUILTIN
98 progprintf(argc, argv)
99 #else
100 main(argc, argv)
101 #endif
102 	int argc;
103 	char *argv[];
104 {
105 	static char *skip1, *skip2;
106 	int ch, end, fieldwidth, precision;
107 	char convch, nextch, *format, *fmt, *start;
108 
109 	while ((ch = getopt(argc, argv, "")) != -1)
110 		switch (ch) {
111 		case '?':
112 		default:
113 			usage();
114 			return (1);
115 		}
116 	argc -= optind;
117 	argv += optind;
118 
119 	if (argc < 1) {
120 		usage();
121 		return (1);
122 	}
123 
124 	/*
125 	 * Basic algorithm is to scan the format string for conversion
126 	 * specifications -- once one is found, find out if the field
127 	 * width or precision is a '*'; if it is, gather up value.  Note,
128 	 * format strings are reused as necessary to use up the provided
129 	 * arguments, arguments of zero/null string are provided to use
130 	 * up the format string.
131 	 */
132 	skip1 = "#-+ 0";
133 	skip2 = "0123456789";
134 
135 	escape(fmt = format = *argv);		/* backslash interpretation */
136 	gargv = ++argv;
137 	for (;;) {
138 		end = 0;
139 		/* find next format specification */
140 next:		for (start = fmt;; ++fmt) {
141 			if (!*fmt) {
142 				/* avoid infinite loop */
143 				if (end == 1) {
144 					warnx1("missing format character",
145 					    NULL, NULL);
146 					return (1);
147 				}
148 				end = 1;
149 				if (fmt > start)
150 					(void)printf("%s", start);
151 				if (!*gargv)
152 					return (0);
153 				fmt = format;
154 				goto next;
155 			}
156 			/* %% prints a % */
157 			if (*fmt == '%') {
158 				if (*++fmt != '%')
159 					break;
160 				*fmt++ = '\0';
161 				(void)printf("%s", start);
162 				goto next;
163 			}
164 		}
165 
166 		/* skip to field width */
167 		for (; strchr(skip1, *fmt); ++fmt);
168 		if (*fmt == '*') {
169 			if (getint(&fieldwidth))
170 				return (1);
171 			++fmt;
172 		} else {
173 			fieldwidth = 0;
174 
175 			/* skip to possible '.', get following precision */
176 			for (; strchr(skip2, *fmt); ++fmt);
177 		}
178 		if (*fmt == '.') {
179 			/* precision present? */
180 			++fmt;
181 			if (*fmt == '*') {
182 				if (getint(&precision))
183 					return (1);
184 				++fmt;
185 			} else {
186 				precision = 0;
187 
188 				/* skip to conversion char */
189 				for (; strchr(skip2, *fmt); ++fmt);
190 			}
191 		} else
192 			precision = 0;
193 		if (!*fmt) {
194 			warnx1("missing format character", NULL, NULL);
195 			return (1);
196 		}
197 
198 		convch = *fmt;
199 		nextch = *++fmt;
200 		*fmt = '\0';
201 		switch(convch) {
202 		case 'c': {
203 			char p;
204 
205 			p = getchr();
206 			PF(start, p);
207 			break;
208 		}
209 		case 's': {
210 			char *p;
211 
212 			p = getstr();
213 			PF(start, p);
214 			break;
215 		}
216 		case 'd': case 'i': case 'o': case 'u': case 'x': case 'X': {
217 			long p;
218 			char *f;
219 
220 			if ((f = mklong(start, convch)) == NULL)
221 				return (1);
222 			if (getlong(&p))
223 				return (1);
224 			PF(f, p);
225 			break;
226 		}
227 		case 'e': case 'E': case 'f': case 'g': case 'G': {
228 			double p;
229 
230 			p = getdouble();
231 			PF(start, p);
232 			break;
233 		}
234 		default:
235 			warnx2("illegal format character %c", convch, NULL);
236 			return (1);
237 		}
238 		*fmt = nextch;
239 	}
240 	/* NOTREACHED */
241 }
242 
243 static char *
244 mklong(str, ch)
245 	char *str;
246 	int ch;
247 {
248 	static char copy[64];
249 	int len;
250 
251 	len = strlen(str) + 2;
252 	memmove(copy, str, len - 3);
253 	copy[len - 3] = 'l';
254 	copy[len - 2] = ch;
255 	copy[len - 1] = '\0';
256 	return (copy);
257 }
258 
259 static void
260 escape(fmt)
261 	register char *fmt;
262 {
263 	register char *store;
264 	register int value, c;
265 
266 	for (store = fmt; (c = *fmt); ++fmt, ++store) {
267 		if (c != '\\') {
268 			*store = c;
269 			continue;
270 		}
271 		switch (*++fmt) {
272 		case '\0':		/* EOS, user error */
273 			*store = '\\';
274 			*++store = '\0';
275 			return;
276 		case '\\':		/* backslash */
277 		case '\'':		/* single quote */
278 			*store = *fmt;
279 			break;
280 		case 'a':		/* bell/alert */
281 			*store = '\7';
282 			break;
283 		case 'b':		/* backspace */
284 			*store = '\b';
285 			break;
286 		case 'f':		/* form-feed */
287 			*store = '\f';
288 			break;
289 		case 'n':		/* newline */
290 			*store = '\n';
291 			break;
292 		case 'r':		/* carriage-return */
293 			*store = '\r';
294 			break;
295 		case 't':		/* horizontal tab */
296 			*store = '\t';
297 			break;
298 		case 'v':		/* vertical tab */
299 			*store = '\13';
300 			break;
301 					/* octal constant */
302 		case '0': case '1': case '2': case '3':
303 		case '4': case '5': case '6': case '7':
304 			for (c = 3, value = 0;
305 			    c-- && *fmt >= '0' && *fmt <= '7'; ++fmt) {
306 				value <<= 3;
307 				value += *fmt - '0';
308 			}
309 			--fmt;
310 			*store = value;
311 			break;
312 		default:
313 			*store = *fmt;
314 			break;
315 		}
316 	}
317 	*store = '\0';
318 }
319 
320 static int
321 getchr()
322 {
323 	if (!*gargv)
324 		return ('\0');
325 	return ((int)**gargv++);
326 }
327 
328 static char *
329 getstr()
330 {
331 	if (!*gargv)
332 		return ("");
333 	return (*gargv++);
334 }
335 
336 static char *Number = "+-.0123456789";
337 static int
338 getint(ip)
339 	int *ip;
340 {
341 	long val;
342 
343 	if (getlong(&val))
344 		return (1);
345 	if (val > INT_MAX) {
346 		warnx3("%s: %s", *gargv, strerror(ERANGE));
347 		return (1);
348 	}
349 	*ip = val;
350 	return (0);
351 }
352 
353 static int
354 getlong(lp)
355 	long *lp;
356 {
357 	long val;
358 	char *ep;
359 
360 	if (!*gargv) {
361 		*lp = 0;
362 		return (0);
363 	}
364 	if (strchr(Number, **gargv)) {
365 		errno = 0;
366 		val = strtol(*gargv, &ep, 0);
367 		if (*ep != '\0') {
368 			warnx2("%s: illegal number", *gargv, NULL);
369 			return (1);
370 		}
371 		if (errno == ERANGE)
372 			if (val == LONG_MAX) {
373 				warnx3("%s: %s", *gargv, strerror(ERANGE));
374 				return (1);
375 			}
376 			if (val == LONG_MIN) {
377 				warnx3("%s: %s", *gargv, strerror(ERANGE));
378 				return (1);
379 			}
380 
381 		*lp = val;
382 		++gargv;
383 		return (0);
384 	}
385 	*lp =  (long)asciicode();
386 	return (0);
387 }
388 
389 static double
390 getdouble()
391 {
392 	if (!*gargv)
393 		return ((double)0);
394 	if (strchr(Number, **gargv))
395 		return (atof(*gargv++));
396 	return ((double)asciicode());
397 }
398 
399 static int
400 asciicode()
401 {
402 	register int ch;
403 
404 	ch = **gargv;
405 	if (ch == '\'' || ch == '"')
406 		ch = (*gargv)[1];
407 	++gargv;
408 	return (ch);
409 }
410 
411 static void
412 usage()
413 {
414 	(void)fprintf(stderr, "usage: printf format [arg ...]\n");
415 }
416