1 /*	$NetBSD: printching.c,v 1.5 2011/08/31 16:24:55 plunky Exp $	*/
2 
3 /*
4  * Copyright (c) 1988, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Guy Harris.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  * @(#)ching.phx.c	8.1 (Berkeley) 5/31/93
39  */
40 
41 /*
42  * printching - Print NROFF/TROFF source of change, given the line values.
43  */
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include "ching.h"
48 #include "pathnames.h"
49 
50 static int changes(void);
51 static int codem(int a);
52 static int doahex(void);
53 static void phx(int hexagram, int flag);
54 
55 static const struct {
56 	int	lines;		/* encoded value of lines */
57 	int	trinum;		/* trigram number */
58 } table[] = {
59 	{ 777, 0 },		/* 1 */
60 	{ 887, 1 },		/* 4 */
61 	{ 878, 2 },		/* 6 */
62 	{ 788, 3 },		/* 7 */
63 	{ 888, 4 },		/* 8 */
64 	{ 778, 5 },		/* 5 */
65 	{ 787, 6 },		/* 3 */
66 	{ 877, 7 },		/* 2 */
67 };
68 
69 /*
70  * Gives hexagram number from two component trigrams.
71  */
72 static const int crosstab[8][8] = {
73 	{1,  34, 5,  26, 11, 9,  14, 43},
74 	{25, 51, 3,  27, 24, 42, 21, 17},
75 	{6,  40, 29, 4,  7,  59, 64, 47},
76 	{33, 62, 39, 52, 15, 53, 56, 31},
77 	{12, 16, 8,  23, 2,  20, 35, 45},
78 	{44, 32, 48, 18, 46, 57, 50, 28},
79 	{13, 55, 63, 22, 36, 37, 30, 49},
80 	{10, 54, 60, 41, 19, 61, 38, 58}
81 };
82 
83 static int trigrams[6];
84 static int moving[6];
85 
86 static FILE *chingf;		/* stream to read the hexagram file */
87 
88 int
89 main(int argc, char **argv)
90 {
91 	char *hexptr;		/* pointer to string of lines */
92 	char hexstr[6+1];	/* buffer for reading lines in */
93 	int i;
94 
95 	if (argc < 2)
96 		hexptr = fgets(hexstr, 6+1, stdin);
97 	else
98 		hexptr = argv[1];
99 	if (hexptr == NULL || strlen(hexptr) != 6) {
100 		fprintf(stderr, "What kind of a change is THAT?!?\n");
101 		exit(1);
102 	}
103 	for (i = 0; i < 6; i++) {
104 		trigrams[i] = hexptr[i] - '0';
105 		if (trigrams[i] == 6 || trigrams[i] == 9)
106 			moving[i] = 1;
107 		else
108 			moving[i] = 0;
109 	}
110 	if ((chingf = fopen(_PATH_HEX, "r")) == NULL) {
111 		fprintf(stderr, "ching: can't read %s\n", _PATH_HEX);
112 		exit(2);
113 	}
114 	phx(doahex(), 0);
115 	if (changes())
116 		phx(doahex(), 1);
117 	exit(0);
118 }
119 
120 /*
121  * Compute the hexagram number, given the trigrams.
122  */
123 static int
124 doahex(void)
125 {
126 	int lower, upper;	/* encoded values of lower and upper trigrams */
127 	int lnum = 0, unum = 0;	/* indices of upper and lower trigrams */
128 	int i;
129 
130 	lower = codem(0);
131 	upper = codem(3);
132 	for (i = 0; i < 8; i++) {
133 		if (table[i].lines == lower)
134 			 lnum = table[i].trinum;
135 		if (table[i].lines == upper)
136 			 unum = table[i].trinum;
137 	}
138 	return(crosstab[lnum][unum]);
139 }
140 
141 /*
142  * Encode a trigram as a 3-digit number; the digits, from left to right,
143  * represent the lines.  7 is a solid (yang) line, 8 is a broken (yin) line.
144  */
145 static int
146 codem(int a)
147 {
148 	int code, i;
149 	int factor[3];
150 
151 	factor[0] = 1;
152 	factor[1] = 10;
153 	factor[2] = 100;
154 	code = 0;
155 
156 	for (i = a; i < a + 3; i++) {
157 		switch(trigrams[i]) {
158 
159 		case YYANG:
160 		case OYANG:
161 			code += factor[i%3]*7;
162 			break;
163 
164 		case OYIN:
165 		case YYIN:
166 			code += factor[i%3]*8;
167 			break;
168 		}
169 	}
170 	return(code);
171 }
172 
173 /*
174  * Compute the changes based on moving lines; return 1 if any lines moved,
175  * 0 if no lines moved.
176  */
177 static int
178 changes(void)
179 {
180 	int cflag;
181 	int i;
182 
183 	cflag = 0;
184 	for (i = 0; i < 6; i++) {
185 		if (trigrams[i] == OYIN) {
186 			trigrams[i] = YYANG;
187 			cflag++;
188 		} else if (trigrams[i] == OYANG) {
189 			trigrams[i] = YYIN;
190 			cflag++;
191 		}
192 	}
193 	return(cflag);
194 }
195 
196 /*
197  * Print the NROFF/TROFF source of a hexagram, given the hexagram number;
198  * if flag is 0, print the entire source; if flag is 1, ignore the meanings
199  * of the lines.
200  */
201 static void
202 phx(int hexagram, int flag)
203 {
204 	char textln[128+1];		/* buffer for text line */
205 	char *lp;			/* pointer into buffer */
206 	int thishex;			/* number of hexagram just read */
207 	int lineno;			/* number of line read in */
208 	int allmoving;			/* 1 if all lines are moving */
209 	int i;
210 
211 	/*
212 	 * Search for the hexagram; it begins with a line of the form
213 	 * .H <hexagram number> <other data>.
214 	 */
215 	rewind(chingf);
216 	for (;;) {
217 		if (fgets(textln, sizeof(textln), chingf) == NULL) {
218 			fprintf(stderr, "ching: Hexagram %d missing\n",
219 			    hexagram);
220 			exit(3);
221 		}
222 		lp = &textln[0];
223 		if (*lp++ != '.' || *lp++ != 'H')
224 			continue;
225 		while (*lp++ == ' ')
226 			;
227 		lp--;
228 		thishex = atoi(lp);
229 		if (thishex < 1 || thishex > 64)
230 			continue;
231 		if (thishex == hexagram)
232 			break;
233 	}
234 
235 	/*
236 	 * Print up to the line commentary, which ends with a line of the form
237 	 * .L <position> <value>
238 	 */
239 	fputs(textln, stdout);
240 	for (;;) {
241 		if (fgets(textln, sizeof(textln), chingf) == NULL) {
242 			fprintf(stderr, "ching: Hexagram %d malformed\n",
243 			    hexagram);
244 			exit(3);
245 		}
246 		lp = &textln[0];
247 		if (*lp++ == '.') {
248 			if (*lp++ == 'L')
249 				break;
250 		}
251 		fputs(textln, stdout);
252 	}
253 
254 	/*
255 	 * Now print the line commentaries, if this is the first hexagram.
256 	 */
257 	if (flag)
258 		return;
259 
260 	/*
261 	 * If a line is moving, print its commentary.
262 	 * The text of the commentary ends with a line either of the form
263 	 * .L <position> <value>
264 	 * or of the form
265 	 * .LA <value>
266 	 * or of the form
267 	 * .H <hexagram number> <other arguments>
268 	 */
269 	allmoving = 1;
270 	for (i = 0; i < 6; i++) {
271 		while (*lp++ == ' ')
272 			;
273 		lp--;
274 		lineno = atoi(lp);
275 		if (i + 1 != lineno) {
276 			fprintf(stderr, "ching: Hexagram %d malformed\n",
277 			    hexagram);
278 			exit(3);
279 		}
280 		if (moving[i])
281 			fputs(textln, stdout);
282 		else
283 			allmoving = 0;
284 		for (;;) {
285 			if (fgets(textln, sizeof(textln), chingf) == NULL)
286 				break;
287 			lp = &textln[0];
288 			if (*lp++ == '.' && (*lp == 'L' || *lp == 'H')) {
289 				lp++;
290 				break;
291 			}
292 			if (moving[i])
293 				fputs(textln, stdout);
294 		}
295 	}
296 
297 	/*
298 	 * If all the lines are moving, print the commentary for that; it
299 	 * ends with a line of the form
300 	 * .H <hexagram number> <other arguments>
301 	 */
302 	if (*lp == 'A' && allmoving) {
303 		fputs(textln, stdout);
304 		for (;;) {
305 			if (fgets(textln, sizeof(textln), chingf) == NULL)
306 				break;
307 			lp = &textln[0];
308 			if (*lp++ == '.' || *lp++ == 'H')
309 				break;
310 			fputs(textln, stdout);
311 		}
312 	}
313 }
314