xref: /freebsd/usr.bin/number/number.c (revision 1db64f89363c97858961c4df0b7d02f3223723cf)
1 /*
2  * Copyright (c) 1988, 1993, 1994
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. 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 #include <sys/types.h>
31 
32 #include <ctype.h>
33 #include <err.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37 #include <unistd.h>
38 
39 #define	MAXNUM		65		/* Biggest number we handle. */
40 
41 static const char	*name1[] = {
42 	"",		"one",		"two",		"three",
43 	"four",		"five",		"six",		"seven",
44 	"eight",	"nine",		"ten",		"eleven",
45 	"twelve",	"thirteen",	"fourteen",	"fifteen",
46 	"sixteen",	"seventeen",	"eighteen",	"nineteen",
47 },
48 		*name2[] = {
49 	"",		"ten",		"twenty",	"thirty",
50 	"forty",	"fifty",	"sixty",	"seventy",
51 	"eighty",	"ninety",
52 },
53 		*name3[] = {
54 	"hundred",	"thousand",	"million",	"billion",
55 	"trillion",	"quadrillion",	"quintillion",	"sextillion",
56 	"septillion",	"octillion",	"nonillion",	"decillion",
57 	"undecillion",	"duodecillion",	"tredecillion",	"quattuordecillion",
58 	"quindecillion",		"sexdecillion",
59 	"septendecillion",		"octodecillion",
60 	"novemdecillion",		"vigintillion",
61 };
62 
63 static void	convert(char *);
64 static int	number(char *, int);
65 static void	pfract(int);
66 static int	unit(int, char *);
67 static void	usage(void);
68 
69 static int lflag;
70 
71 int
72 main(int argc, char *argv[])
73 {
74 	int ch, first;
75 	char line[256];
76 
77 	lflag = 0;
78 	while ((ch = getopt(argc, argv, "l")) != -1)
79 		switch (ch) {
80 		case 'l':
81 			lflag = 1;
82 			break;
83 		case '?':
84 		default:
85 			usage();
86 		}
87 	argc -= optind;
88 	argv += optind;
89 
90 	if (*argv == NULL)
91 		for (first = 1;
92 		    fgets(line, sizeof(line), stdin) != NULL; first = 0) {
93 			if (strchr(line, '\n') == NULL)
94 				errx(1, "line too long.");
95 			if (!first)
96 				(void)printf("...\n");
97 			convert(line);
98 		}
99 	else
100 		for (first = 1; *argv != NULL; first = 0, ++argv) {
101 			if (!first)
102 				(void)printf("...\n");
103 			convert(*argv);
104 		}
105 	exit(0);
106 }
107 
108 static void
109 convert(char *line)
110 {
111 	int flen, len, rval;
112 	char *p, *fraction;
113 
114 	flen = 0;
115 	fraction = NULL;
116 	for (p = line; *p != '\0' && *p != '\n'; ++p) {
117 		if (isblank(*p)) {
118 			if (p == line) {
119 				++line;
120 				continue;
121 			}
122 			goto badnum;
123 		}
124 		if (isdigit(*p))
125 			continue;
126 		switch (*p) {
127 		case '.':
128 			if (fraction != NULL)
129 				goto badnum;
130 			fraction = p + 1;
131 			*p = '\0';
132 			break;
133 		case '-':
134 			if (p == line)
135 				break;
136 			/* FALLTHROUGH */
137 		default:
138 badnum:			errx(1, "illegal number: %s", line);
139 			break;
140 		}
141 	}
142 	*p = '\0';
143 
144 	if ((len = strlen(line)) > MAXNUM ||
145 	    (fraction != NULL && ((flen = strlen(fraction)) > MAXNUM)))
146 		errx(1, "number too large, max %d digits.", MAXNUM);
147 
148 	if (*line == '-') {
149 		(void)printf("minus%s", lflag ? " " : "\n");
150 		++line;
151 		--len;
152 	}
153 
154 	rval = len > 0 ? unit(len, line) : 0;
155 	if (fraction != NULL && flen != 0)
156 		for (p = fraction; *p != '\0'; ++p)
157 			if (*p != '0') {
158 				if (rval)
159 					(void)printf("%sand%s",
160 					    lflag ? " " : "",
161 					    lflag ? " " : "\n");
162 				if (unit(flen, fraction)) {
163 					if (lflag)
164 						(void)printf(" ");
165 					pfract(flen);
166 					rval = 1;
167 				}
168 				break;
169 			}
170 	if (!rval)
171 		(void)printf("zero%s", lflag ? "" : ".\n");
172 	if (lflag)
173 		(void)printf("\n");
174 }
175 
176 static int
177 unit(int len, char *p)
178 {
179 	int off, rval;
180 
181 	rval = 0;
182 	if (len > 3) {
183 		if (len % 3) {
184 			off = len % 3;
185 			len -= off;
186 			if (number(p, off)) {
187 				rval = 1;
188 				(void)printf(" %s%s",
189 				    name3[len / 3], lflag ? " " : ".\n");
190 			}
191 			p += off;
192 		}
193 		for (; len > 3; p += 3) {
194 			len -= 3;
195 			if (number(p, 3)) {
196 				rval = 1;
197 				(void)printf(" %s%s",
198 				    name3[len / 3], lflag ? " " : ".\n");
199 			}
200 		}
201 	}
202 	if (number(p, len)) {
203 		if (!lflag)
204 			(void)printf(".\n");
205 		rval = 1;
206 	}
207 	return (rval);
208 }
209 
210 static int
211 number(char *p, int len)
212 {
213 	int val, rval;
214 
215 	rval = 0;
216 	switch (len) {
217 	case 3:
218 		if (*p != '0') {
219 			rval = 1;
220 			(void)printf("%s hundred", name1[*p - '0']);
221 		}
222 		++p;
223 		/* FALLTHROUGH */
224 	case 2:
225 		val = (p[1] - '0') + (p[0] - '0') * 10;
226 		if (val) {
227 			if (rval)
228 				(void)printf(" ");
229 			if (val < 20)
230 				(void)printf("%s", name1[val]);
231 			else {
232 				(void)printf("%s", name2[val / 10]);
233 				if (val % 10)
234 					(void)printf("-%s", name1[val % 10]);
235 			}
236 			rval = 1;
237 		}
238 		break;
239 	case 1:
240 		if (*p != '0') {
241 			rval = 1;
242 			(void)printf("%s", name1[*p - '0']);
243 		}
244 	}
245 	return (rval);
246 }
247 
248 static void
249 pfract(int len)
250 {
251 	static char const * const pref[] = { "", "ten-", "hundred-" };
252 
253 	switch(len) {
254 	case 1:
255 		(void)printf("tenths.\n");
256 		break;
257 	case 2:
258 		(void)printf("hundredths.\n");
259 		break;
260 	default:
261 		(void)printf("%s%sths.\n", pref[len % 3], name3[len / 3]);
262 		break;
263 	}
264 }
265 
266 static void
267 usage(void)
268 {
269 	(void)fprintf(stderr, "usage: number [-l] [# ...]\n");
270 	exit(1);
271 }
272