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quiz.c revision 1.18 
      1 /*	$NetBSD: quiz.c,v 1.18 2000/05/08 07:56:05 mycroft Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1991, 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  * Jim R. Oldroyd at The Instruction Set and Keith Gabryelski at
      9  * Commodore Business Machines.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  * 3. All advertising materials mentioning features or use of this software
     20  *    must display the following acknowledgement:
     21  *	This product includes software developed by the University of
     22  *	California, Berkeley and its contributors.
     23  * 4. Neither the name of the University nor the names of its contributors
     24  *    may be used to endorse or promote products derived from this software
     25  *    without specific prior written permission.
     26  *
     27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     37  * SUCH DAMAGE.
     38  */
     39 
     40 #include <sys/cdefs.h>
     41 #ifndef lint
     42 __COPYRIGHT("@(#) Copyright (c) 1991, 1993\n\
     43 	The Regents of the University of California.  All rights reserved.\n");
     44 #endif /* not lint */
     45 
     46 #ifndef lint
     47 #if 0
     48 static char sccsid[] = "@(#)quiz.c	8.3 (Berkeley) 5/4/95";
     49 #else
     50 __RCSID("$NetBSD: quiz.c,v 1.18 2000/05/08 07:56:05 mycroft Exp $");
     51 #endif
     52 #endif /* not lint */
     53 
     54 #include <sys/types.h>
     55 
     56 #include <ctype.h>
     57 #include <errno.h>
     58 #include <stdio.h>
     59 #include <stdlib.h>
     60 #include <string.h>
     61 #include <ctype.h>
     62 #include <err.h>
     63 #include <time.h>
     64 #include <unistd.h>
     65 #include "quiz.h"
     66 #include "pathnames.h"
     67 
     68 static QE qlist;
     69 static int catone, cattwo, tflag;
     70 static u_int qsize;
     71 
     72 char	*appdstr __P((char *, const char *, size_t));
     73 void	 downcase __P((char *));
     74 void	 get_cats __P((char *, char *));
     75 void	 get_file __P((const char *));
     76 int	 main __P((int, char *[]));
     77 const char	*next_cat __P((const char *));
     78 void	 quiz __P((void));
     79 void	 score __P((u_int, u_int, u_int));
     80 void	 show_index __P((void));
     81 void	 usage __P((void)) __attribute__((__noreturn__));
     82 
     83 int
     84 main(argc, argv)
     85 	int argc;
     86 	char *argv[];
     87 {
     88 	int ch;
     89 	const char *indexfile;
     90 
     91 	/* Revoke setgid privileges */
     92 	setgid(getgid());
     93 
     94 	indexfile = _PATH_QUIZIDX;
     95 	while ((ch = getopt(argc, argv, "i:t")) != -1)
     96 		switch(ch) {
     97 		case 'i':
     98 			indexfile = optarg;
     99 			break;
    100 		case 't':
    101 			tflag = 1;
    102 			break;
    103 		case '?':
    104 		default:
    105 			usage();
    106 		}
    107 	argc -= optind;
    108 	argv += optind;
    109 
    110 	switch(argc) {
    111 	case 0:
    112 		get_file(indexfile);
    113 		show_index();
    114 		break;
    115 	case 2:
    116 		get_file(indexfile);
    117 		get_cats(argv[0], argv[1]);
    118 		quiz();
    119 		break;
    120 	default:
    121 		usage();
    122 	}
    123 	exit(0);
    124 }
    125 
    126 void
    127 get_file(file)
    128 	const char *file;
    129 {
    130 	FILE *fp;
    131 	QE *qp;
    132 	size_t len;
    133 	char *lp;
    134 
    135 	if ((fp = fopen(file, "r")) == NULL)
    136 		err(1, "%s", file);
    137 
    138 	/*
    139 	 * XXX
    140 	 * Should really free up space from any earlier read list
    141 	 * but there are no reverse pointers to do so with.
    142 	 */
    143 	qp = &qlist;
    144 	qsize = 0;
    145 	while ((lp = fgetln(fp, &len)) != NULL) {
    146 		if (lp[len - 1] == '\n')
    147 			lp[--len] = '\0';
    148 		if (qp->q_text && qp->q_text[strlen(qp->q_text) - 1] == '\\')
    149 			qp->q_text = appdstr(qp->q_text, lp, len);
    150 		else {
    151 			if ((qp->q_next = malloc(sizeof(QE))) == NULL)
    152 				errx(1, "malloc");
    153 			qp = qp->q_next;
    154 			if ((qp->q_text = malloc(len + 1)) == NULL)
    155 				errx(1, "malloc");
    156 			strncpy(qp->q_text, lp, len);
    157 			qp->q_text[len] = '\0';
    158 			qp->q_asked = qp->q_answered = FALSE;
    159 			qp->q_next = NULL;
    160 			++qsize;
    161 		}
    162 	}
    163 	(void)fclose(fp);
    164 }
    165 
    166 void
    167 show_index()
    168 {
    169 	QE *qp;
    170 	const char *p, *s;
    171 	FILE *pf;
    172 	const char *pager;
    173 
    174 	if (!isatty(1))
    175 		pager = "cat";
    176 	else {
    177 		if (!(pager = getenv("PAGER")) || (*pager == 0))
    178 			pager = _PATH_PAGER;
    179 	}
    180 	if ((pf = popen(pager, "w")) == NULL)
    181 		err(1, "%s", pager);
    182 	(void)fprintf(pf, "Subjects:\n\n");
    183 	for (qp = qlist.q_next; qp; qp = qp->q_next) {
    184 		for (s = next_cat(qp->q_text); s; s = next_cat(s)) {
    185 			if (!rxp_compile(s))
    186 				errx(1, "%s", rxperr);
    187 			if ((p = rxp_expand()) != NULL)
    188 				(void)fprintf(pf, "%s ", p);
    189 		}
    190 		(void)fprintf(pf, "\n");
    191 	}
    192 	(void)fprintf(pf, "\n%s\n%s\n%s\n",
    193 "For example, \"quiz victim killer\" prints a victim's name and you reply",
    194 "with the killer, and \"quiz killer victim\" works the other way around.",
    195 "Type an empty line to get the correct answer.");
    196 	(void)pclose(pf);
    197 }
    198 
    199 void
    200 get_cats(cat1, cat2)
    201 	char *cat1, *cat2;
    202 {
    203 	QE *qp;
    204 	int i;
    205 	const char *s;
    206 
    207 	downcase(cat1);
    208 	downcase(cat2);
    209 	for (qp = qlist.q_next; qp; qp = qp->q_next) {
    210 		s = next_cat(qp->q_text);
    211 		catone = cattwo = i = 0;
    212 		while (s) {
    213 			if (!rxp_compile(s))
    214 				errx(1, "%s", rxperr);
    215 			i++;
    216 			if (rxp_match(cat1))
    217 				catone = i;
    218 			if (rxp_match(cat2))
    219 				cattwo = i;
    220 			s = next_cat(s);
    221 		}
    222 		if (catone && cattwo && catone != cattwo) {
    223 			if (!rxp_compile(qp->q_text))
    224 				errx(1, "%s", rxperr);
    225 			get_file(rxp_expand());
    226 			return;
    227 		}
    228 	}
    229 	errx(1, "invalid categories");
    230 }
    231 
    232 void
    233 quiz()
    234 {
    235 	QE *qp;
    236 	int i;
    237 	size_t len;
    238 	u_int guesses, rights, wrongs;
    239 	int next;
    240 	char *answer, *t, question[LINE_SZ];
    241 	const char *s;
    242 
    243 	srandom(time(NULL));
    244 	guesses = rights = wrongs = 0;
    245 	for (;;) {
    246 		if (qsize == 0)
    247 			break;
    248 		next = random() % qsize;
    249 		qp = qlist.q_next;
    250 		for (i = 0; i < next; i++)
    251 			qp = qp->q_next;
    252 		while (qp && qp->q_answered)
    253 			qp = qp->q_next;
    254 		if (!qp) {
    255 			qsize = next;
    256 			continue;
    257 		}
    258 		if (tflag && random() % 100 > 20) {
    259 			/* repeat questions in tutorial mode */
    260 			while (qp && (!qp->q_asked || qp->q_answered))
    261 				qp = qp->q_next;
    262 			if (!qp)
    263 				continue;
    264 		}
    265 		s = qp->q_text;
    266 		for (i = 0; i < catone - 1; i++)
    267 			s = next_cat(s);
    268 		if (!rxp_compile(s))
    269 			errx(1, "%s", rxperr);
    270 		t = rxp_expand();
    271 		if (!t || *t == '\0') {
    272 			qp->q_answered = TRUE;
    273 			continue;
    274 		}
    275 		(void)strcpy(question, t);
    276 		s = qp->q_text;
    277 		for (i = 0; i < cattwo - 1; i++)
    278 			s = next_cat(s);
    279 		if (!rxp_compile(s))
    280 			errx(1, "%s", rxperr);
    281 		t = rxp_expand();
    282 		if (!t || *t == '\0') {
    283 			qp->q_answered = TRUE;
    284 			continue;
    285 		}
    286 		qp->q_asked = TRUE;
    287 		(void)printf("%s?\n", question);
    288 		for (;; ++guesses) {
    289 			if ((answer = fgetln(stdin, &len)) == NULL ||
    290 			    answer[len - 1] != '\n') {
    291 				score(rights, wrongs, guesses);
    292 				exit(0);
    293 			}
    294 			answer[len - 1] = '\0';
    295 			downcase(answer);
    296 			if (rxp_match(answer)) {
    297 				(void)printf("Right!\n");
    298 				++rights;
    299 				qp->q_answered = TRUE;
    300 				break;
    301 			}
    302 			if (*answer == '\0') {
    303 				(void)printf("%s\n", t);
    304 				++wrongs;
    305 				if (!tflag)
    306 					qp->q_answered = TRUE;
    307 				break;
    308 			}
    309 			(void)printf("What?\n");
    310 		}
    311 	}
    312 	score(rights, wrongs, guesses);
    313 }
    314 
    315 const char *
    316 next_cat(s)
    317 	const char *	s;
    318 {
    319 	int esc;
    320 
    321 	esc = 0;
    322 	for (;;)
    323 		switch (*s++) {
    324 		case '\0':
    325 			return (NULL);
    326 		case '\\':
    327 			esc = 1;
    328 			break;
    329 		case ':':
    330 			if (!esc)
    331 				return (s);
    332 		default:
    333 			esc = 0;
    334 			break;
    335 		}
    336 	/* NOTREACHED */
    337 }
    338 
    339 char *
    340 appdstr(s, tp, len)
    341 	char *s;
    342 	const char *tp;
    343 	size_t len;
    344 {
    345 	char *mp;
    346 	const char *sp;
    347 	int ch;
    348 	char *m;
    349 
    350 	if ((m = malloc(strlen(s) + len + 1)) == NULL)
    351 		errx(1, "malloc");
    352 	for (mp = m, sp = s; (*mp++ = *sp++) != '\0'; )
    353 		;
    354 	--mp;
    355 	if (*(mp - 1) == '\\')
    356 		--mp;
    357 
    358 	while ((ch = *mp++ = *tp++) && ch != '\n')
    359 		;
    360 	*mp = '\0';
    361 
    362 	free(s);
    363 	return (m);
    364 }
    365 
    366 void
    367 score(r, w, g)
    368 	u_int r, w, g;
    369 {
    370 	(void)printf("Rights %d, wrongs %d,", r, w);
    371 	if (g)
    372 		(void)printf(" extra guesses %d,", g);
    373 	(void)printf(" score %d%%\n", (r + w + g) ? r * 100 / (r + w + g) : 0);
    374 }
    375 
    376 void
    377 downcase(p)
    378 	char *p;
    379 {
    380 	int ch;
    381 
    382 	for (; (ch = *p) != '\0'; ++p)
    383 		if (isascii(ch) && isupper(ch))
    384 			*p = tolower(ch);
    385 }
    386 
    387 void
    388 usage()
    389 {
    390 	(void)fprintf(stderr, "quiz [-t] [-i file] category1 category2\n");
    391 	exit(1);
    392 }
    393