xref: /netbsd-src/usr.bin/seq/seq.c (revision 404fbe5fb94ca1e054339640cabb2801ce52dd30)
1 /*
2  * Copyright (c) 2005 The NetBSD Foundation, Inc.
3  * All rights reserved.
4  *
5  * This code is derived from software contributed to The NetBSD Foundation
6  * by Brian Ginsbach.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
18  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
19  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
21  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27  * POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 #ifndef lint
32 __COPYRIGHT("@(#) Copyright (c) 2005\
33  The NetBSD Foundation, Inc.  All rights reserved.");
34 __RCSID("$NetBSD: seq.c,v 1.5 2008/07/21 14:19:26 lukem Exp $");
35 #endif /* not lint */
36 
37 #include <ctype.h>
38 #include <err.h>
39 #include <errno.h>
40 #include <math.h>
41 #include <locale.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <unistd.h>
46 
47 #define ZERO	'0'
48 #define SPACE	' '
49 
50 #define MAX(a, b)	(((a) < (b))? (b) : (a))
51 #define ISSIGN(c)	((int)(c) == '-' || (int)(c) == '+')
52 #define ISEXP(c)	((int)(c) == 'e' || (int)(c) == 'E')
53 #define ISODIGIT(c)	((int)(c) >= '0' && (int)(c) <= '7')
54 
55 /* Globals */
56 
57 const char *decimal_point = ".";	/* default */
58 char default_format[] = { "%g" };	/* default */
59 
60 /* Prototypes */
61 
62 double e_atof(const char *);
63 
64 int decimal_places(const char *);
65 int main(int, char *[]);
66 int numeric(const char *);
67 int valid_format(const char *);
68 
69 char *generate_format(double, double, double, int, char);
70 char *unescape(char *);
71 
72 /*
73  * The seq command will print out a numeric sequence from 1, the default,
74  * to a user specified upper limit by 1.  The lower bound and increment
75  * maybe indicated by the user on the command line.  The sequence can
76  * be either whole, the default, or decimal numbers.
77  */
78 int
79 main(int argc, char *argv[])
80 {
81 	int c = 0, errflg = 0;
82 	int equalize = 0;
83 	double first = 1.0;
84 	double last = 0.0;
85 	double incr = 0.0;
86 	struct lconv *locale;
87 	char *fmt = NULL;
88 	const char *sep = "\n";
89 	const char *term = NULL;
90 	char pad = ZERO;
91 
92 	/* Determine the locale's decimal point. */
93 	locale = localeconv();
94 	if (locale && locale->decimal_point && locale->decimal_point[0] != '\0')
95 		decimal_point = locale->decimal_point;
96 
97 	/*
98          * Process options, but handle negative numbers separately
99          * least they trip up getopt(3).
100          */
101 	while ((optind < argc) && !numeric(argv[optind]) &&
102 	    (c = getopt(argc, argv, "f:hs:t:w")) != -1) {
103 
104 		switch (c) {
105 		case 'f':	/* format (plan9) */
106 			fmt = optarg;
107 			equalize = 0;
108 			break;
109 		case 's':	/* separator (GNU) */
110 			sep = unescape(optarg);
111 			break;
112 		case 't':	/* terminator (new) */
113 			term = unescape(optarg);
114 			break;
115 		case 'w':	/* equal width (plan9) */
116 			if (!fmt)
117 				if (equalize++)
118 					pad = SPACE;
119 			break;
120 		case 'h':	/* help (GNU) */
121 		default:
122 			errflg++;
123 			break;
124 		}
125 	}
126 
127 	argc -= optind;
128 	argv += optind;
129 	if (argc < 1 || argc > 3)
130 		errflg++;
131 
132 	if (errflg) {
133 		fprintf(stderr,
134 		    "usage: %s [-w] [-f format] [-s string] [-t string] [first [incr]] last\n",
135 		    getprogname());
136 		exit(1);
137 	}
138 
139 	last = e_atof(argv[argc - 1]);
140 
141 	if (argc > 1)
142 		first = e_atof(argv[0]);
143 
144 	if (argc > 2) {
145 		incr = e_atof(argv[1]);
146 		/* Plan 9/GNU don't do zero */
147 		if (incr == 0.0)
148 			errx(1, "zero %screment", (first < last)? "in" : "de");
149 	}
150 
151 	/* default is one for Plan 9/GNU work alike */
152 	if (incr == 0.0)
153 		incr = (first < last) ? 1.0 : -1.0;
154 
155 	if (incr <= 0.0 && first < last)
156 		errx(1, "needs positive increment");
157 
158 	if (incr >= 0.0 && first > last)
159 		errx(1, "needs negative decrement");
160 
161 	if (fmt != NULL) {
162 		if (!valid_format(fmt))
163 			errx(1, "invalid format string: `%s'", fmt);
164 		fmt = unescape(fmt);
165 		/*
166 	         * XXX to be bug for bug compatible with Plan 9 add a
167 		 * newline if none found at the end of the format string.
168 		 */
169 	} else
170 		fmt = generate_format(first, incr, last, equalize, pad);
171 
172 	if (incr > 0) {
173 		for (; first <= last; first += incr) {
174 			printf(fmt, first);
175 			fputs(sep, stdout);
176 		}
177 	} else {
178 		for (; first >= last; first += incr) {
179 			printf(fmt, first);
180 			fputs(sep, stdout);
181 		}
182 	}
183 	if (term != NULL)
184 		fputs(term, stdout);
185 
186 	return (0);
187 }
188 
189 /*
190  * numeric - verify that string is numeric
191  */
192 int
193 numeric(const char *s)
194 {
195 	int seen_decimal_pt, decimal_pt_len;
196 
197 	/* skip any sign */
198 	if (ISSIGN((unsigned char)*s))
199 		s++;
200 
201 	seen_decimal_pt = 0;
202 	decimal_pt_len = strlen(decimal_point);
203 	while (*s) {
204 		if (!isdigit((unsigned char)*s)) {
205 			if (!seen_decimal_pt &&
206 			    strncmp(s, decimal_point, decimal_pt_len) == 0) {
207 				s += decimal_pt_len;
208 				seen_decimal_pt = 1;
209 				continue;
210 			}
211 			if (ISEXP((unsigned char)*s)) {
212 				s++;
213 				if (ISSIGN((unsigned char)*s)) {
214 					s++;
215 					continue;
216 				}
217 			}
218 			break;
219 		}
220 		s++;
221 	}
222 	return (*s == '\0');
223 }
224 
225 /*
226  * valid_format - validate user specified format string
227  */
228 int
229 valid_format(const char *fmt)
230 {
231 	int conversions = 0;
232 
233 	while (*fmt != '\0') {
234 		/* scan for conversions */
235 		if (*fmt != '\0' && *fmt != '%') {
236 			do {
237 				fmt++;
238 			} while (*fmt != '\0' && *fmt != '%');
239 		}
240 		/* scan a conversion */
241 		if (*fmt != '\0') {
242 			do {
243 				fmt++;
244 
245 				/* ok %% */
246 				if (*fmt == '%') {
247 					fmt++;
248 					break;
249 				}
250 				/* valid conversions */
251 				if (strchr("eEfgG", *fmt) &&
252 				    conversions++ < 1) {
253 					fmt++;
254 					break;
255 				}
256 				/* flags, width and precsision */
257 				if (isdigit((unsigned char)*fmt) ||
258 				    strchr("+- 0#.", *fmt))
259 					continue;
260 
261 				/* oops! bad conversion format! */
262 				return (0);
263 			} while (*fmt != '\0');
264 		}
265 	}
266 
267 	return (conversions <= 1);
268 }
269 
270 /*
271  * unescape - handle C escapes in a string
272  */
273 char *
274 unescape(char *orig)
275 {
276 	char c, *cp, *new = orig;
277 	int i;
278 
279 	for (cp = orig; (*orig = *cp); cp++, orig++) {
280 		if (*cp != '\\')
281 			continue;
282 
283 		switch (*++cp) {
284 		case 'a':	/* alert (bell) */
285 			*orig = '\a';
286 			continue;
287 		case 'b':	/* backspace */
288 			*orig = '\b';
289 			continue;
290 		case 'e':	/* escape */
291 			*orig = '\e';
292 			continue;
293 		case 'f':	/* formfeed */
294 			*orig = '\f';
295 			continue;
296 		case 'n':	/* newline */
297 			*orig = '\n';
298 			continue;
299 		case 'r':	/* carriage return */
300 			*orig = '\r';
301 			continue;
302 		case 't':	/* horizontal tab */
303 			*orig = '\t';
304 			continue;
305 		case 'v':	/* vertical tab */
306 			*orig = '\v';
307 			continue;
308 		case '\\':	/* backslash */
309 			*orig = '\\';
310 			continue;
311 		case '\'':	/* single quote */
312 			*orig = '\'';
313 			continue;
314 		case '\"':	/* double quote */
315 			*orig = '"';
316 			continue;
317 		case '0':
318 		case '1':
319 		case '2':
320 		case '3':	/* octal */
321 		case '4':
322 		case '5':
323 		case '6':
324 		case '7':	/* number */
325 			for (i = 0, c = 0;
326 			     ISODIGIT((unsigned char)*cp) && i < 3;
327 			     i++, cp++) {
328 				c <<= 3;
329 				c |= (*cp - '0');
330 			}
331 			*orig = c;
332 			--cp;
333 			continue;
334 		case 'x':	/* hexidecimal number */
335 			cp++;	/* skip 'x' */
336 			for (i = 0, c = 0;
337 			     isxdigit((unsigned char)*cp) && i < 2;
338 			     i++, cp++) {
339 				c <<= 4;
340 				if (isdigit((unsigned char)*cp))
341 					c |= (*cp - '0');
342 				else
343 					c |= ((toupper((unsigned char)*cp) -
344 					    'A') + 10);
345 			}
346 			*orig = c;
347 			--cp;
348 			continue;
349 		default:
350 			--cp;
351 			break;
352 		}
353 	}
354 
355 	return (new);
356 }
357 
358 /*
359  * e_atof - convert an ASCII string to a double
360  *	exit if string is not a valid double, or if converted value would
361  *	cause overflow or underflow
362  */
363 double
364 e_atof(const char *num)
365 {
366 	char *endp;
367 	double dbl;
368 
369 	errno = 0;
370 	dbl = strtod(num, &endp);
371 
372 	if (errno == ERANGE)
373 		/* under or overflow */
374 		err(2, "%s", num);
375 	else if (*endp != '\0')
376 		/* "junk" left in number */
377 		errx(2, "invalid floating point argument: %s", num);
378 
379 	/* zero shall have no sign */
380 	if (dbl == -0.0)
381 		dbl = 0;
382 	return (dbl);
383 }
384 
385 /*
386  * decimal_places - count decimal places in a number (string)
387  */
388 int
389 decimal_places(const char *number)
390 {
391 	int places = 0;
392 	char *dp;
393 
394 	/* look for a decimal point */
395 	if ((dp = strstr(number, decimal_point))) {
396 		dp += strlen(decimal_point);
397 
398 		while (isdigit((unsigned char)*dp++))
399 			places++;
400 	}
401 	return (places);
402 }
403 
404 /*
405  * generate_format - create a format string
406  *
407  * XXX to be bug for bug compatable with Plan9 and GNU return "%g"
408  * when "%g" prints as "%e" (this way no width adjustments are made)
409  */
410 char *
411 generate_format(double first, double incr, double last, int equalize, char pad)
412 {
413 	static char buf[256];
414 	char cc = '\0';
415 	int precision, width1, width2, places;
416 
417 	if (equalize == 0)
418 		return (default_format);
419 
420 	/* figure out "last" value printed */
421 	if (first > last)
422 		last = first - incr * floor((first - last) / incr);
423 	else
424 		last = first + incr * floor((last - first) / incr);
425 
426 	sprintf(buf, "%g", incr);
427 	if (strchr(buf, 'e'))
428 		cc = 'e';
429 	precision = decimal_places(buf);
430 
431 	width1 = sprintf(buf, "%g", first);
432 	if (strchr(buf, 'e'))
433 		cc = 'e';
434 	if ((places = decimal_places(buf)))
435 		width1 -= (places + strlen(decimal_point));
436 
437 	precision = MAX(places, precision);
438 
439 	width2 = sprintf(buf, "%g", last);
440 	if (strchr(buf, 'e'))
441 		cc = 'e';
442 	if ((places = decimal_places(buf)))
443 		width2 -= (places + strlen(decimal_point));
444 
445 	if (precision) {
446 		sprintf(buf, "%%%c%d.%d%c", pad,
447 		    MAX(width1, width2) + (int) strlen(decimal_point) +
448 		    precision, precision, (cc) ? cc : 'f');
449 	} else {
450 		sprintf(buf, "%%%c%d%c", pad, MAX(width1, width2),
451 		    (cc) ? cc : 'g');
452 	}
453 
454 	return (buf);
455 }
456