xref: /netbsd/usr.bin/seq/seq.c (revision 7572fbf5)
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 1.12 2021/03/20 22:10:17 cheusov 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 numeric(const char *);
66 int valid_format(const char *);
67 
68 char *generate_format(double, double, double, int, char);
69 char *unescape(char *);
70 
71 /*
72  * The seq command will print out a numeric sequence from 1, the default,
73  * to a user specified upper limit by 1.  The lower bound and increment
74  * maybe indicated by the user on the command line.  The sequence can
75  * be either whole, the default, or decimal numbers.
76  */
77 int
main(int argc,char * argv[])78 main(int argc, char *argv[])
79 {
80 	int c = 0, errflg = 0;
81 	int equalize = 0;
82 	double first = 1.0;
83 	double last = 0.0;
84 	double incr = 0.0;
85 	struct lconv *locale;
86 	char *fmt = NULL;
87 	const char *sep = "\n";
88 	const char *term = "\n";
89 	char pad = ZERO;
90 
91 	/* Determine the locale's decimal point. */
92 	locale = localeconv();
93 	if (locale && locale->decimal_point && locale->decimal_point[0] != '\0')
94 		decimal_point = locale->decimal_point;
95 
96 	/*
97          * Process options, but handle negative numbers separately
98          * least they trip up getopt(3).
99          */
100 	while ((optind < argc) && !numeric(argv[optind]) &&
101 	    (c = getopt(argc, argv, "f:hs:t:w")) != -1) {
102 
103 		switch (c) {
104 		case 'f':	/* format (plan9) */
105 			fmt = optarg;
106 			equalize = 0;
107 			break;
108 		case 's':	/* separator (GNU) */
109 			sep = unescape(optarg);
110 			break;
111 		case 't':	/* terminator (new) */
112 			term = unescape(optarg);
113 			break;
114 		case 'w':	/* equal width (plan9) */
115 			if (!fmt)
116 				if (equalize++)
117 					pad = SPACE;
118 			break;
119 		case 'h':	/* help (GNU) */
120 		default:
121 			errflg++;
122 			break;
123 		}
124 	}
125 
126 	argc -= optind;
127 	argv += optind;
128 	if (argc < 1 || argc > 3)
129 		errflg++;
130 
131 	if (errflg) {
132 		fprintf(stderr,
133 		    "usage: %s [-w] [-f format] [-s string] [-t string] [first [incr]] last\n",
134 		    getprogname());
135 		exit(1);
136 	}
137 
138 	last = e_atof(argv[argc - 1]);
139 
140 	if (argc > 1)
141 		first = e_atof(argv[0]);
142 
143 	if (argc > 2) {
144 		incr = e_atof(argv[1]);
145 		/* Plan 9/GNU don't do zero */
146 		if (incr == 0.0)
147 			errx(1, "zero %screment", (first < last)? "in" : "de");
148 	}
149 
150 	/* default is one for Plan 9/GNU work alike */
151 	if (incr == 0.0)
152 		incr = (first < last) ? 1.0 : -1.0;
153 
154 	if (incr <= 0.0 && first < last)
155 		errx(1, "needs positive increment");
156 
157 	if (incr >= 0.0 && first > last)
158 		errx(1, "needs negative decrement");
159 
160 	if (fmt != NULL) {
161 		if (!valid_format(fmt))
162 			errx(1, "invalid format string: `%s'", fmt);
163 		fmt = unescape(fmt);
164 		if (!valid_format(fmt))
165 			errx(1, "invalid format string");
166 		/*
167 	         * XXX to be bug for bug compatible with Plan 9 add a
168 		 * newline if none found at the end of the format string.
169 		 */
170 	} else
171 		fmt = generate_format(first, incr, last, equalize, pad);
172 
173 	if (incr > 0) {
174 		printf(fmt, first);
175 		for (first += incr; first <= last; first += incr) {
176 			fputs(sep, stdout);
177 			printf(fmt, first);
178 		}
179 	} else {
180 		printf(fmt, first);
181 		for (first += incr; first >= last; first += incr) {
182 			fputs(sep, stdout);
183 			printf(fmt, first);
184 		}
185 	}
186 	if (term != NULL)
187 		fputs(term, stdout);
188 
189 	return (0);
190 }
191 
192 /*
193  * numeric - verify that string is numeric
194  */
195 int
numeric(const char * s)196 numeric(const char *s)
197 {
198 	int seen_decimal_pt, decimal_pt_len;
199 
200 	/* skip any sign */
201 	if (ISSIGN((unsigned char)*s))
202 		s++;
203 
204 	seen_decimal_pt = 0;
205 	decimal_pt_len = strlen(decimal_point);
206 	while (*s) {
207 		if (!isdigit((unsigned char)*s)) {
208 			if (!seen_decimal_pt &&
209 			    strncmp(s, decimal_point, decimal_pt_len) == 0) {
210 				s += decimal_pt_len;
211 				seen_decimal_pt = 1;
212 				continue;
213 			}
214 			if (ISEXP((unsigned char)*s)) {
215 				s++;
216 				/* optional sign */
217 				if (ISSIGN((unsigned char)*s))
218 					s++;
219 				continue;
220 			}
221 			break;
222 		}
223 		s++;
224 	}
225 	return (*s == '\0');
226 }
227 
228 /*
229  * valid_format - validate user specified format string
230  */
231 int
valid_format(const char * fmt)232 valid_format(const char *fmt)
233 {
234 	unsigned conversions = 0;
235 
236 	while (*fmt != '\0') {
237 		/* scan for conversions */
238 		if (*fmt != '%') {
239 			fmt++;
240 			continue;
241 		}
242 		fmt++;
243 
244 		/* allow %% but not things like %10% */
245 		if (*fmt == '%') {
246 			fmt++;
247 			continue;
248 		}
249 
250 		/* flags */
251 		while (*fmt != '\0' && strchr("#0- +'", *fmt)) {
252 			fmt++;
253 		}
254 
255 		/* field width */
256 		while (*fmt != '\0' && strchr("0123456789", *fmt)) {
257 			fmt++;
258 		}
259 
260 		/* precision */
261 		if (*fmt == '.') {
262 			fmt++;
263 			while (*fmt != '\0' && strchr("0123456789", *fmt)) {
264 				fmt++;
265 			}
266 		}
267 
268 		/* conversion */
269 		switch (*fmt) {
270 		    case 'A':
271 		    case 'a':
272 		    case 'E':
273 		    case 'e':
274 		    case 'F':
275 		    case 'f':
276 		    case 'G':
277 		    case 'g':
278 			/* floating point formats are accepted */
279 			conversions++;
280 			break;
281 		    default:
282 			/* anything else is not */
283 			return 0;
284 		}
285 	}
286 
287 	return (conversions <= 1);
288 }
289 
290 /*
291  * unescape - handle C escapes in a string
292  */
293 char *
unescape(char * orig)294 unescape(char *orig)
295 {
296 	char c, *cp, *new = orig;
297 	int i;
298 
299 	for (cp = orig; (*orig = *cp); cp++, orig++) {
300 		if (*cp != '\\')
301 			continue;
302 
303 		switch (*++cp) {
304 		case 'a':	/* alert (bell) */
305 			*orig = '\a';
306 			continue;
307 		case 'b':	/* backspace */
308 			*orig = '\b';
309 			continue;
310 		case 'e':	/* escape */
311 			*orig = '\x1B';
312 			continue;
313 		case 'f':	/* formfeed */
314 			*orig = '\f';
315 			continue;
316 		case 'n':	/* newline */
317 			*orig = '\n';
318 			continue;
319 		case 'r':	/* carriage return */
320 			*orig = '\r';
321 			continue;
322 		case 't':	/* horizontal tab */
323 			*orig = '\t';
324 			continue;
325 		case 'v':	/* vertical tab */
326 			*orig = '\v';
327 			continue;
328 		case '\\':	/* backslash */
329 			*orig = '\\';
330 			continue;
331 		case '\'':	/* single quote */
332 			*orig = '\'';
333 			continue;
334 		case '\"':	/* double quote */
335 			*orig = '"';
336 			continue;
337 		case '0':
338 		case '1':
339 		case '2':
340 		case '3':	/* octal */
341 		case '4':
342 		case '5':
343 		case '6':
344 		case '7':	/* number */
345 			for (i = 0, c = 0;
346 			     ISODIGIT((unsigned char)*cp) && i < 3;
347 			     i++, cp++) {
348 				c <<= 3;
349 				c |= (*cp - '0');
350 			}
351 			*orig = c;
352 			--cp;
353 			continue;
354 		case 'x':	/* hexadecimal number */
355 			cp++;	/* skip 'x' */
356 			for (i = 0, c = 0;
357 			     isxdigit((unsigned char)*cp) && i < 2;
358 			     i++, cp++) {
359 				c <<= 4;
360 				if (isdigit((unsigned char)*cp))
361 					c |= (*cp - '0');
362 				else
363 					c |= ((toupper((unsigned char)*cp) -
364 					    'A') + 10);
365 			}
366 			*orig = c;
367 			--cp;
368 			continue;
369 		default:
370 			--cp;
371 			break;
372 		}
373 	}
374 
375 	return (new);
376 }
377 
378 /*
379  * e_atof - convert an ASCII string to a double
380  *	exit if string is not a valid double, or if converted value would
381  *	cause overflow or underflow
382  */
383 double
e_atof(const char * num)384 e_atof(const char *num)
385 {
386 	char *endp;
387 	double dbl;
388 
389 	errno = 0;
390 	dbl = strtod(num, &endp);
391 
392 	if (errno == ERANGE)
393 		/* under or overflow */
394 		err(2, "%s", num);
395 	else if (*endp != '\0')
396 		/* "junk" left in number */
397 		errx(2, "invalid floating point argument: %s", num);
398 
399 	/* zero shall have no sign */
400 	if (dbl == -0.0)
401 		dbl = 0;
402 	return (dbl);
403 }
404 
405 /*
406  * decimal_places - count decimal places in a number (string)
407  */
408 int
decimal_places(const char * number)409 decimal_places(const char *number)
410 {
411 	int places = 0;
412 	char *dp;
413 
414 	/* look for a decimal point */
415 	if ((dp = strstr(number, decimal_point))) {
416 		dp += strlen(decimal_point);
417 
418 		while (isdigit((unsigned char)*dp++))
419 			places++;
420 	}
421 	return (places);
422 }
423 
424 /*
425  * generate_format - create a format string
426  *
427  * XXX to be bug for bug compatible with Plan9 and GNU return "%g"
428  * when "%g" prints as "%e" (this way no width adjustments are made)
429  */
430 char *
generate_format(double first,double incr,double last,int equalize,char pad)431 generate_format(double first, double incr, double last, int equalize, char pad)
432 {
433 	static char buf[256];
434 	char cc = '\0';
435 	int precision, width1, width2, places;
436 
437 	if (equalize == 0)
438 		return (default_format);
439 
440 	/* figure out "last" value printed */
441 	if (first > last)
442 		last = first - incr * floor((first - last) / incr);
443 	else
444 		last = first + incr * floor((last - first) / incr);
445 
446 	sprintf(buf, "%g", incr);
447 	if (strchr(buf, 'e'))
448 		cc = 'e';
449 	precision = decimal_places(buf);
450 
451 	width1 = sprintf(buf, "%g", first);
452 	if (strchr(buf, 'e'))
453 		cc = 'e';
454 	if ((places = decimal_places(buf)))
455 		width1 -= (places + strlen(decimal_point));
456 
457 	precision = MAX(places, precision);
458 
459 	width2 = sprintf(buf, "%g", last);
460 	if (strchr(buf, 'e'))
461 		cc = 'e';
462 	if ((places = decimal_places(buf)))
463 		width2 -= (places + strlen(decimal_point));
464 
465 	if (precision) {
466 		sprintf(buf, "%%%c%d.%d%c", pad,
467 		    MAX(width1, width2) + (int) strlen(decimal_point) +
468 		    precision, precision, (cc) ? cc : 'f');
469 	} else {
470 		sprintf(buf, "%%%c%d%c", pad, MAX(width1, width2),
471 		    (cc) ? cc : 'g');
472 	}
473 
474 	return (buf);
475 }
476