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quiz.c revision 1.23 
      1 /*	$NetBSD: quiz.c,v 1.23 2008/07/20 01:03:22 lukem 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. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  */
     35 
     36 #include <sys/cdefs.h>
     37 #ifndef lint
     38 __COPYRIGHT("@(#) Copyright (c) 1991, 1993\
     39  The Regents of the University of California.  All rights reserved.");
     40 #endif /* not lint */
     41 
     42 #ifndef lint
     43 #if 0
     44 static char sccsid[] = "@(#)quiz.c	8.3 (Berkeley) 5/4/95";
     45 #else
     46 __RCSID("$NetBSD: quiz.c,v 1.23 2008/07/20 01:03:22 lukem Exp $");
     47 #endif
     48 #endif /* not lint */
     49 
     50 #include <sys/types.h>
     51 
     52 #include <ctype.h>
     53 #include <errno.h>
     54 #include <stdio.h>
     55 #include <stdlib.h>
     56 #include <string.h>
     57 #include <err.h>
     58 #include <time.h>
     59 #include <unistd.h>
     60 #include "quiz.h"
     61 #include "pathnames.h"
     62 
     63 static QE qlist;
     64 static int catone, cattwo, tflag;
     65 static u_int qsize;
     66 
     67 char	*appdstr(char *, const char *, size_t);
     68 void	 downcase(char *);
     69 void	 get_cats(char *, char *);
     70 void	 get_file(const char *);
     71 int	 main(int, char *[]);
     72 const char	*next_cat(const char *);
     73 void	 quiz(void);
     74 void	 score(u_int, u_int, u_int);
     75 void	 show_index(void);
     76 void	 usage(void) __dead;
     77 
     78 int
     79 main(argc, argv)
     80 	int argc;
     81 	char *argv[];
     82 {
     83 	int ch;
     84 	const char *indexfile;
     85 
     86 	/* Revoke setgid privileges */
     87 	setgid(getgid());
     88 
     89 	indexfile = _PATH_QUIZIDX;
     90 	while ((ch = getopt(argc, argv, "i:t")) != -1)
     91 		switch(ch) {
     92 		case 'i':
     93 			indexfile = optarg;
     94 			break;
     95 		case 't':
     96 			tflag = 1;
     97 			break;
     98 		case '?':
     99 		default:
    100 			usage();
    101 		}
    102 	argc -= optind;
    103 	argv += optind;
    104 
    105 	switch(argc) {
    106 	case 0:
    107 		get_file(indexfile);
    108 		show_index();
    109 		break;
    110 	case 2:
    111 		get_file(indexfile);
    112 		get_cats(argv[0], argv[1]);
    113 		quiz();
    114 		break;
    115 	default:
    116 		usage();
    117 	}
    118 	exit(0);
    119 }
    120 
    121 void
    122 get_file(file)
    123 	const char *file;
    124 {
    125 	FILE *fp;
    126 	QE *qp;
    127 	size_t len;
    128 	char *lp;
    129 
    130 	if ((fp = fopen(file, "r")) == NULL)
    131 		err(1, "%s", file);
    132 
    133 	/*
    134 	 * XXX
    135 	 * Should really free up space from any earlier read list
    136 	 * but there are no reverse pointers to do so with.
    137 	 */
    138 	qp = &qlist;
    139 	qsize = 0;
    140 	while ((lp = fgetln(fp, &len)) != NULL) {
    141 		if (lp[len - 1] == '\n')
    142 			lp[--len] = '\0';
    143 		if (qp->q_text && qp->q_text[strlen(qp->q_text) - 1] == '\\')
    144 			qp->q_text = appdstr(qp->q_text, lp, len);
    145 		else {
    146 			if ((qp->q_next = malloc(sizeof(QE))) == NULL)
    147 				errx(1, "malloc");
    148 			qp = qp->q_next;
    149 			if ((qp->q_text = malloc(len + 1)) == NULL)
    150 				errx(1, "malloc");
    151 			strncpy(qp->q_text, lp, len);
    152 			qp->q_text[len] = '\0';
    153 			qp->q_asked = qp->q_answered = FALSE;
    154 			qp->q_next = NULL;
    155 			++qsize;
    156 		}
    157 	}
    158 	(void)fclose(fp);
    159 }
    160 
    161 void
    162 show_index()
    163 {
    164 	QE *qp;
    165 	const char *p, *s;
    166 	FILE *pf;
    167 	const char *pager;
    168 
    169 	if (!isatty(1))
    170 		pager = "cat";
    171 	else {
    172 		if (!(pager = getenv("PAGER")) || (*pager == 0))
    173 			pager = _PATH_PAGER;
    174 	}
    175 	if ((pf = popen(pager, "w")) == NULL)
    176 		err(1, "%s", pager);
    177 	(void)fprintf(pf, "Subjects:\n\n");
    178 	for (qp = qlist.q_next; qp; qp = qp->q_next) {
    179 		for (s = next_cat(qp->q_text); s; s = next_cat(s)) {
    180 			if (!rxp_compile(s))
    181 				errx(1, "%s", rxperr);
    182 			if ((p = rxp_expand()) != NULL)
    183 				(void)fprintf(pf, "%s ", p);
    184 		}
    185 		(void)fprintf(pf, "\n");
    186 	}
    187 	(void)fprintf(pf, "\n%s\n%s\n%s\n",
    188 "For example, \"quiz victim killer\" prints a victim's name and you reply",
    189 "with the killer, and \"quiz killer victim\" works the other way around.",
    190 "Type an empty line to get the correct answer.");
    191 	(void)pclose(pf);
    192 }
    193 
    194 void
    195 get_cats(cat1, cat2)
    196 	char *cat1, *cat2;
    197 {
    198 	QE *qp;
    199 	int i;
    200 	const char *s;
    201 
    202 	downcase(cat1);
    203 	downcase(cat2);
    204 	for (qp = qlist.q_next; qp; qp = qp->q_next) {
    205 		s = next_cat(qp->q_text);
    206 		catone = cattwo = i = 0;
    207 		while (s) {
    208 			if (!rxp_compile(s))
    209 				errx(1, "%s", rxperr);
    210 			i++;
    211 			if (rxp_match(cat1))
    212 				catone = i;
    213 			if (rxp_match(cat2))
    214 				cattwo = i;
    215 			s = next_cat(s);
    216 		}
    217 		if (catone && cattwo && catone != cattwo) {
    218 			if (!rxp_compile(qp->q_text))
    219 				errx(1, "%s", rxperr);
    220 			get_file(rxp_expand());
    221 			return;
    222 		}
    223 	}
    224 	errx(1, "invalid categories");
    225 }
    226 
    227 void
    228 quiz()
    229 {
    230 	QE *qp;
    231 	int i;
    232 	size_t len;
    233 	u_int guesses, rights, wrongs;
    234 	int next;
    235 	char *answer, *t, question[LINE_SZ];
    236 	const char *s;
    237 
    238 	srandom(time(NULL));
    239 	guesses = rights = wrongs = 0;
    240 	for (;;) {
    241 		if (qsize == 0)
    242 			break;
    243 		next = random() % qsize;
    244 		qp = qlist.q_next;
    245 		for (i = 0; i < next; i++)
    246 			qp = qp->q_next;
    247 		while (qp && qp->q_answered)
    248 			qp = qp->q_next;
    249 		if (!qp) {
    250 			qsize = next;
    251 			continue;
    252 		}
    253 		if (tflag && random() % 100 > 20) {
    254 			/* repeat questions in tutorial mode */
    255 			while (qp && (!qp->q_asked || qp->q_answered))
    256 				qp = qp->q_next;
    257 			if (!qp)
    258 				continue;
    259 		}
    260 		s = qp->q_text;
    261 		for (i = 0; i < catone - 1; i++)
    262 			s = next_cat(s);
    263 		if (!rxp_compile(s))
    264 			errx(1, "%s", rxperr);
    265 		t = rxp_expand();
    266 		if (!t || *t == '\0') {
    267 			qp->q_answered = TRUE;
    268 			continue;
    269 		}
    270 		(void)strcpy(question, t);
    271 		s = qp->q_text;
    272 		for (i = 0; i < cattwo - 1; i++)
    273 			s = next_cat(s);
    274 		if (!rxp_compile(s))
    275 			errx(1, "%s", rxperr);
    276 		t = rxp_expand();
    277 		if (!t || *t == '\0') {
    278 			qp->q_answered = TRUE;
    279 			continue;
    280 		}
    281 		qp->q_asked = TRUE;
    282 		(void)printf("%s?\n", question);
    283 		for (;; ++guesses) {
    284 			if ((answer = fgetln(stdin, &len)) == NULL ||
    285 			    answer[len - 1] != '\n') {
    286 				score(rights, wrongs, guesses);
    287 				exit(0);
    288 			}
    289 			answer[len - 1] = '\0';
    290 			downcase(answer);
    291 			if (rxp_match(answer)) {
    292 				(void)printf("Right!\n");
    293 				++rights;
    294 				qp->q_answered = TRUE;
    295 				break;
    296 			}
    297 			if (*answer == '\0') {
    298 				(void)printf("%s\n", t);
    299 				++wrongs;
    300 				if (!tflag)
    301 					qp->q_answered = TRUE;
    302 				break;
    303 			}
    304 			(void)printf("What?\n");
    305 		}
    306 	}
    307 	score(rights, wrongs, guesses);
    308 }
    309 
    310 const char *
    311 next_cat(s)
    312 	const char *	s;
    313 {
    314 	int esc;
    315 
    316 	esc = 0;
    317 	for (;;)
    318 		switch (*s++) {
    319 		case '\0':
    320 			return (NULL);
    321 		case '\\':
    322 			esc = 1;
    323 			break;
    324 		case ':':
    325 			if (!esc)
    326 				return (s);
    327 		default:
    328 			esc = 0;
    329 			break;
    330 		}
    331 	/* NOTREACHED */
    332 }
    333 
    334 char *
    335 appdstr(s, tp, len)
    336 	char *s;
    337 	const char *tp;
    338 	size_t len;
    339 {
    340 	char *mp;
    341 	const char *sp;
    342 	int ch;
    343 	char *m;
    344 
    345 	if ((m = malloc(strlen(s) + len + 1)) == NULL)
    346 		errx(1, "malloc");
    347 	for (mp = m, sp = s; (*mp++ = *sp++) != '\0'; )
    348 		;
    349 	--mp;
    350 	if (*(mp - 1) == '\\')
    351 		--mp;
    352 
    353 	while ((ch = *mp++ = *tp++) && ch != '\n')
    354 		;
    355 	*mp = '\0';
    356 
    357 	free(s);
    358 	return (m);
    359 }
    360 
    361 void
    362 score(r, w, g)
    363 	u_int r, w, g;
    364 {
    365 	(void)printf("Rights %d, wrongs %d,", r, w);
    366 	if (g)
    367 		(void)printf(" extra guesses %d,", g);
    368 	(void)printf(" score %d%%\n", (r + w + g) ? r * 100 / (r + w + g) : 0);
    369 }
    370 
    371 void
    372 downcase(p)
    373 	char *p;
    374 {
    375 	int ch;
    376 
    377 	for (; (ch = *p) != '\0'; ++p)
    378 		if (isascii(ch) && isupper(ch))
    379 			*p = tolower(ch);
    380 }
    381 
    382 void
    383 usage()
    384 {
    385 	(void)fprintf(stderr, "quiz [-t] [-i file] category1 category2\n");
    386 	exit(1);
    387 }
    388