xref: /freebsd/usr.bin/jot/jot.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 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. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 /*
33  * jot - print sequential or random data
34  *
35  * Author:  John Kunze, Office of Comp. Affairs, UCB
36  */
37 
38 #include <sys/capsicum.h>
39 #include <capsicum_helpers.h>
40 #include <ctype.h>
41 #include <err.h>
42 #include <errno.h>
43 #include <limits.h>
44 #include <stdio.h>
45 #include <stdint.h>
46 #include <stdlib.h>
47 #include <stdbool.h>
48 #include <string.h>
49 #include <time.h>
50 #include <unistd.h>
51 
52 /* Defaults */
53 #define	REPS_DEF	100
54 #define	BEGIN_DEF	1
55 #define	ENDER_DEF	100
56 #define	STEP_DEF	1
57 
58 /* Flags of options that have been set */
59 #define HAVE_STEP	1
60 #define HAVE_ENDER	2
61 #define HAVE_BEGIN	4
62 #define HAVE_REPS	8
63 
64 #define	is_default(s)	(*(s) == 0 || strcmp((s), "-") == 0)
65 
66 static bool	boring;
67 static int	prec = -1;
68 static bool	longdata;
69 static bool	intdata;
70 static bool	chardata;
71 static bool	nosign;
72 static const	char *sepstring = "\n";
73 static char	format[BUFSIZ];
74 
75 static void	getformat(void);
76 static int	getprec(const char *);
77 static int	putdata(double, bool);
78 static void	usage(void);
79 
80 int
81 main(int argc, char **argv)
82 {
83 	cap_rights_t rights;
84 	bool	have_format = false;
85 	bool	infinity = false;
86 	bool	nofinalnl = false;
87 	bool	randomize = false;
88 	bool	use_random = false;
89 	int	ch;
90 	int	mask = 0;
91 	int	n = 0;
92 	double	begin = BEGIN_DEF;
93 	double	divisor;
94 	double	ender = ENDER_DEF;
95 	double	s = STEP_DEF;
96 	double	x, y;
97 	long	i;
98 	long	reps = REPS_DEF;
99 
100 	if (caph_limit_stdio() < 0)
101 		err(1, "unable to limit rights for stdio");
102 	cap_rights_init(&rights);
103 	if (caph_rights_limit(STDIN_FILENO, &rights) < 0)
104 		err(1, "unable to limit rights for stdin");
105 
106 	/*
107 	 * Cache NLS data, for strerror, for err(3), before entering capability
108 	 * mode.
109 	 */
110 	caph_cache_catpages();
111 
112 	if (caph_enter() < 0)
113 		err(1, "unable to enter capability mode");
114 
115 	while ((ch = getopt(argc, argv, "b:cnp:rs:w:")) != -1)
116 		switch (ch) {
117 		case 'b':
118 			boring = true;
119 			/* FALLTHROUGH */
120 		case 'w':
121 			if (strlcpy(format, optarg, sizeof(format)) >=
122 			    sizeof(format))
123 				errx(1, "-%c word too long", ch);
124 			have_format = true;
125 			break;
126 		case 'c':
127 			chardata = true;
128 			break;
129 		case 'n':
130 			nofinalnl = true;
131 			break;
132 		case 'p':
133 			prec = atoi(optarg);
134 			if (prec < 0)
135 				errx(1, "bad precision value");
136 			have_format = true;
137 			break;
138 		case 'r':
139 			randomize = true;
140 			break;
141 		case 's':
142 			sepstring = optarg;
143 			break;
144 		default:
145 			usage();
146 		}
147 	argc -= optind;
148 	argv += optind;
149 
150 	switch (argc) {	/* examine args right to left, falling thru cases */
151 	case 4:
152 		if (!is_default(argv[3])) {
153 			if (!sscanf(argv[3], "%lf", &s))
154 				errx(1, "bad s value: %s", argv[3]);
155 			mask |= HAVE_STEP;
156 			if (randomize)
157 				use_random = true;
158 		}
159 		/* FALLTHROUGH */
160 	case 3:
161 		if (!is_default(argv[2])) {
162 			if (!sscanf(argv[2], "%lf", &ender))
163 				ender = argv[2][strlen(argv[2])-1];
164 			mask |= HAVE_ENDER;
165 			if (prec < 0)
166 				n = getprec(argv[2]);
167 		}
168 		/* FALLTHROUGH */
169 	case 2:
170 		if (!is_default(argv[1])) {
171 			if (!sscanf(argv[1], "%lf", &begin))
172 				begin = argv[1][strlen(argv[1])-1];
173 			mask |= HAVE_BEGIN;
174 			if (prec < 0)
175 				prec = getprec(argv[1]);
176 			if (n > prec)		/* maximum precision */
177 				prec = n;
178 		}
179 		/* FALLTHROUGH */
180 	case 1:
181 		if (!is_default(argv[0])) {
182 			if (!sscanf(argv[0], "%ld", &reps))
183 				errx(1, "bad reps value: %s", argv[0]);
184 			mask |= HAVE_REPS;
185 		}
186 		break;
187 	case 0:
188 		usage();
189 	default:
190 		errx(1, "too many arguments.  What do you mean by %s?",
191 		    argv[4]);
192 	}
193 	getformat();
194 
195 	if (prec == -1)
196 		prec = 0;
197 
198 	while (mask)	/* 4 bit mask has 1's where last 4 args were given */
199 		switch (mask) {	/* fill in the 0's by default or computation */
200 		case HAVE_STEP:
201 		case HAVE_ENDER:
202 		case HAVE_ENDER | HAVE_STEP:
203 		case HAVE_BEGIN:
204 		case HAVE_BEGIN | HAVE_STEP:
205 			reps = REPS_DEF;
206 			mask |= HAVE_REPS;
207 			break;
208 		case HAVE_BEGIN | HAVE_ENDER:
209 			s = ender > begin ? 1 : -1;
210 			mask |= HAVE_STEP;
211 			break;
212 		case HAVE_BEGIN | HAVE_ENDER | HAVE_STEP:
213 			if (randomize)
214 				reps = REPS_DEF;
215 			else if (s == 0.0)
216 				reps = 0;
217 			else
218 				reps = (ender - begin + s) / s;
219 			if (reps <= 0)
220 				errx(1, "impossible stepsize");
221 			mask = 0;
222 			break;
223 		case HAVE_REPS:
224 		case HAVE_REPS | HAVE_STEP:
225 			begin = BEGIN_DEF;
226 			mask |= HAVE_BEGIN;
227 			break;
228 		case HAVE_REPS | HAVE_ENDER:
229 			s = STEP_DEF;
230 			mask = HAVE_REPS | HAVE_ENDER | HAVE_STEP;
231 			break;
232 		case HAVE_REPS | HAVE_ENDER | HAVE_STEP:
233 			if (randomize)
234 				begin = BEGIN_DEF;
235 			else if (reps == 0)
236 				errx(1, "must specify begin if reps == 0");
237 			begin = ender - reps * s + s;
238 			mask = 0;
239 			break;
240 		case HAVE_REPS | HAVE_BEGIN:
241 			s = STEP_DEF;
242 			mask = HAVE_REPS | HAVE_BEGIN | HAVE_STEP;
243 			break;
244 		case HAVE_REPS | HAVE_BEGIN | HAVE_STEP:
245 			if (randomize)
246 				ender = ENDER_DEF;
247 			else
248 				ender = begin + reps * s - s;
249 			mask = 0;
250 			break;
251 		case HAVE_REPS | HAVE_BEGIN | HAVE_ENDER:
252 			if (!randomize) {
253 				if (reps == 0)
254 					errx(1, "infinite sequences cannot "
255 					    "be bounded");
256 				else if (reps == 1)
257 					s = 0.0;
258 				else
259 					s = (ender - begin) / (reps - 1);
260 			}
261 			mask = 0;
262 			break;
263 		case HAVE_REPS | HAVE_BEGIN | HAVE_ENDER | HAVE_STEP:
264 			/* if reps given and implied, */
265 			if (!randomize && s != 0.0) {
266 				long t = (ender - begin + s) / s;
267 				if (t <= 0)
268 					errx(1, "impossible stepsize");
269 				if (t < reps)		/* take lesser */
270 					reps = t;
271 			}
272 			mask = 0;
273 			break;
274 		default:
275 			errx(1, "bad mask");
276 		}
277 	if (reps == 0)
278 		infinity = true;
279 	if (randomize) {
280 		if (use_random) {
281 			srandom((unsigned long)s);
282 			divisor = (double)INT32_MAX + 1;
283 		} else
284 			divisor = (double)UINT32_MAX + 1;
285 
286 		/*
287 		 * Attempt to DWIM when the user has specified an
288 		 * integer range within that of the random number
289 		 * generator: distribute the numbers equally in
290 		 * the range [begin .. ender].  Jot's default %.0f
291 		 * format would make the appearance of the first and
292 		 * last specified value half as likely as the rest.
293 		 */
294 		if (!have_format && prec == 0 &&
295 		    begin >= 0 && begin < divisor &&
296 		    ender >= 0 && ender < divisor) {
297 			if (begin <= ender)
298 				ender += 1;
299 			else
300 				begin += 1;
301 			nosign = true;
302 			intdata = true;
303 			(void)strlcpy(format,
304 			    chardata ? "%c" : "%u", sizeof(format));
305 		}
306 		x = ender - begin;
307 		for (i = 1; i <= reps || infinity; i++) {
308 			if (use_random)
309 				y = random() / divisor;
310 			else
311 				y = arc4random() / divisor;
312 			if (putdata(y * x + begin, !(reps - i)))
313 				errx(1, "range error in conversion");
314 		}
315 	} else
316 		for (i = 1, x = begin; i <= reps || infinity; i++, x += s)
317 			if (putdata(x, !(reps - i)))
318 				errx(1, "range error in conversion");
319 	if (!nofinalnl)
320 		putchar('\n');
321 	exit(0);
322 }
323 
324 /*
325  * Send x to stdout using the specified format.
326  * Last is  true if this is the set's last value.
327  * Return 0 if OK, or a positive number if the number passed was
328  * outside the range specified by the various flags.
329  */
330 static int
331 putdata(double x, bool last)
332 {
333 
334 	if (boring)
335 		printf("%s", format);
336 	else if (longdata && nosign) {
337 		if (x <= (double)ULONG_MAX && x >= (double)0)
338 			printf(format, (unsigned long)x);
339 		else
340 			return (1);
341 	} else if (longdata) {
342 		if (x <= (double)LONG_MAX && x >= (double)LONG_MIN)
343 			printf(format, (long)x);
344 		else
345 			return (1);
346 	} else if (chardata || (intdata && !nosign)) {
347 		if (x <= (double)INT_MAX && x >= (double)INT_MIN)
348 			printf(format, (int)x);
349 		else
350 			return (1);
351 	} else if (intdata) {
352 		if (x <= (double)UINT_MAX && x >= (double)0)
353 			printf(format, (unsigned int)x);
354 		else
355 			return (1);
356 
357 	} else
358 		printf(format, x);
359 	if (!last)
360 		fputs(sepstring, stdout);
361 
362 	return (0);
363 }
364 
365 static void
366 usage(void)
367 {
368 	fprintf(stderr, "%s\n%s\n",
369 	"usage: jot [-cnr] [-b word] [-w word] [-s string] [-p precision]",
370 	"           [reps [begin [end [s]]]]");
371 	exit(1);
372 }
373 
374 /*
375  * Return the number of digits following the number's decimal point.
376  * Return 0 if no decimal point is found.
377  */
378 static int
379 getprec(const char *str)
380 {
381 	const char	*p;
382 	const char	*q;
383 
384 	for (p = str; *p; p++)
385 		if (*p == '.')
386 			break;
387 	if (!*p)
388 		return (0);
389 	for (q = ++p; *p; p++)
390 		if (!isdigit((unsigned char)*p))
391 			break;
392 	return (p - q);
393 }
394 
395 /*
396  * Set format, intdata, chardata, longdata, and nosign
397  * based on the command line arguments.
398  */
399 static void
400 getformat(void)
401 {
402 	char	*p, *p2;
403 	int dot, hash, space, sign, numbers = 0;
404 	size_t sz;
405 
406 	if (boring)				/* no need to bother */
407 		return;
408 	for (p = format; *p; p++)		/* look for '%' */
409 		if (*p == '%') {
410 			if (p[1] == '%')
411 				p++;		/* leave %% alone */
412 			else
413 				break;
414 		}
415 	sz = sizeof(format) - strlen(format) - 1;
416 	if (!*p && !chardata) {
417 		if (snprintf(p, sz, "%%.%df", prec) >= (int)sz)
418 			errx(1, "-w word too long");
419 	} else if (!*p && chardata) {
420 		if (strlcpy(p, "%c", sz) >= sz)
421 			errx(1, "-w word too long");
422 		intdata = true;
423 	} else if (!*(p+1)) {
424 		if (sz <= 0)
425 			errx(1, "-w word too long");
426 		strcat(format, "%");		/* cannot end in single '%' */
427 	} else {
428 		/*
429 		 * Allow conversion format specifiers of the form
430 		 * %[#][ ][{+,-}][0-9]*[.[0-9]*]? where ? must be one of
431 		 * [l]{d,i,o,u,x} or {f,e,g,E,G,d,o,x,D,O,U,X,c,u}
432 		 */
433 		p2 = p++;
434 		dot = hash = space = sign = numbers = 0;
435 		while (!isalpha((unsigned char)*p)) {
436 			if (isdigit((unsigned char)*p)) {
437 				numbers++;
438 				p++;
439 			} else if ((*p == '#' && !(numbers|dot|sign|space|
440 			    hash++)) ||
441 			    (*p == ' ' && !(numbers|dot|space++)) ||
442 			    ((*p == '+' || *p == '-') && !(numbers|dot|sign++))
443 			    || (*p == '.' && !(dot++)))
444 				p++;
445 			else
446 				goto fmt_broken;
447 		}
448 		if (*p == 'l') {
449 			longdata = true;
450 			if (*++p == 'l') {
451 				if (p[1] != '\0')
452 					p++;
453 				goto fmt_broken;
454 			}
455 		}
456 		switch (*p) {
457 		case 'o': case 'u': case 'x': case 'X':
458 			intdata = nosign = true;
459 			break;
460 		case 'd': case 'i':
461 			intdata = true;
462 			break;
463 		case 'D':
464 			if (!longdata) {
465 				intdata = true;
466 				break;
467 			}
468 		case 'O': case 'U':
469 			if (!longdata) {
470 				intdata = nosign = true;
471 				break;
472 			}
473 		case 'c':
474 			if (!(intdata | longdata)) {
475 				chardata = true;
476 				break;
477 			}
478 		case 'h': case 'n': case 'p': case 'q': case 's': case 'L':
479 		case '$': case '*':
480 			goto fmt_broken;
481 		case 'f': case 'e': case 'g': case 'E': case 'G':
482 			if (!longdata)
483 				break;
484 			/* FALLTHROUGH */
485 		default:
486 fmt_broken:
487 			*++p = '\0';
488 			errx(1, "illegal or unsupported format '%s'", p2);
489 			/* NOTREACHED */
490 		}
491 		while (*++p)
492 			if (*p == '%' && *(p+1) && *(p+1) != '%')
493 				errx(1, "too many conversions");
494 			else if (*p == '%' && *(p+1) == '%')
495 				p++;
496 			else if (*p == '%' && !*(p+1)) {
497 				if (strlcat(format, "%", sizeof(format)) >=
498 				    sizeof(format))
499 					errx(1, "-w word too long");
500 				break;
501 			}
502 	}
503 }
504