quiz/quiz.c

   1 /*      $NetBSD: quiz.c,v 1.20 2004/01/27 20:30:30 jsm 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\n\
  39         The Regents of the University of California.  All rights reserved.\n");
  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 1.20 2004/01/27 20:30:30 jsm 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 <ctype.h>
  58 #include <err.h>
  59 #include <time.h>
  60 #include <unistd.h>
  61 #include "quiz.h"
  62 #include "pathnames.h"
  63
  64 static QE qlist;
  65 static int catone, cattwo, tflag;
  66 static u_int qsize;
  67
  68 char    *appdstr(char *, const char *, size_t);
  69 void     downcase(char *);
  70 void     get_cats(char *, char *);
  71 void     get_file(const char *);
  72 int      main(int, char *[]);
  73 const char      *next_cat(const char *);
  74 void     quiz(void);
  75 void     score(u_int, u_int, u_int);
  76 void     show_index(void);
  77 void     usage(void) __attribute__((__noreturn__));
  78
  79 int
  80 main(argc, argv)
  81         int argc;
  82         char *argv[];
  83 {
  84         int ch;
  85         const char *indexfile;
  86
  87         /* Revoke setgid privileges */
  88         setgid(getgid());
  89
  90         indexfile = _PATH_QUIZIDX;
  91         while ((ch = getopt(argc, argv, "i:t")) != -1)
  92                 switch(ch) {
  93                 case 'i':
  94                         indexfile = optarg;
  95                         break;
  96                 case 't':
  97                         tflag = 1;
  98                         break;
  99                 case '?':
 100                 default:
 101                         usage();
 102                 }
 103         argc -= optind;
 104         argv += optind;
 105
 106         switch(argc) {
 107         case 0:
 108                 get_file(indexfile);
 109                 show_index();
 110                 break;
 111         case 2:
 112                 get_file(indexfile);
 113                 get_cats(argv[0], argv[1]);
 114                 quiz();
 115                 break;
 116         default:
 117                 usage();
 118         }
 119         exit(0);
 120 }
 121
 122 void
 123 get_file(file)
 124         const char *file;
 125 {
 126         FILE *fp;
 127         QE *qp;
 128         size_t len;
 129         char *lp;
 130
 131         if ((fp = fopen(file, "r")) == NULL)
 132                 err(1, "%s", file);
 133
 134         /*
 135          * XXX
 136          * Should really free up space from any earlier read list
 137          * but there are no reverse pointers to do so with.
 138          */
 139         qp = &qlist;
 140         qsize = 0;
 141         while ((lp = fgetln(fp, &len)) != NULL) {
 142                 if (lp[len - 1] == '\n')
 143                         lp[--len] = '\0';
 144                 if (qp->q_text && qp->q_text[strlen(qp->q_text) - 1] == '\\')
 145                         qp->q_text = appdstr(qp->q_text, lp, len);
 146                 else {
 147                         if ((qp->q_next = malloc(sizeof(QE))) == NULL)
 148                                 errx(1, "malloc");
 149                         qp = qp->q_next;
 150                         if ((qp->q_text = malloc(len + 1)) == NULL)
 151                                 errx(1, "malloc");
 152                         strncpy(qp->q_text, lp, len);
 153                         qp->q_text[len] = '\0';
 154                         qp->q_asked = qp->q_answered = FALSE;
 155                         qp->q_next = NULL;
 156                         ++qsize;
 157                 }
 158         }
 159         (void)fclose(fp);
 160 }
 161
 162 void
 163 show_index()
 164 {
 165         QE *qp;
 166         const char *p, *s;
 167         FILE *pf;
 168         const char *pager;
 169
 170         if (!isatty(1))
 171                 pager = "cat";
 172         else {
 173                 if (!(pager = getenv("PAGER")) || (*pager == 0))
 174                         pager = _PATH_PAGER;
 175         }
 176         if ((pf = popen(pager, "w")) == NULL)
 177                 err(1, "%s", pager);
 178         (void)fprintf(pf, "Subjects:\n\n");
 179         for (qp = qlist.q_next; qp; qp = qp->q_next) {
 180                 for (s = next_cat(qp->q_text); s; s = next_cat(s)) {
 181                         if (!rxp_compile(s))
 182                                 errx(1, "%s", rxperr);
 183                         if ((p = rxp_expand()) != NULL)
 184                                 (void)fprintf(pf, "%s ", p);
 185                 }
 186                 (void)fprintf(pf, "\n");
 187         }
 188         (void)fprintf(pf, "\n%s\n%s\n%s\n",
 189 "For example, \"quiz victim killer\" prints a victim's name and you reply",
 190 "with the killer, and \"quiz killer victim\" works the other way around.",
 191 "Type an empty line to get the correct answer.");
 192         (void)pclose(pf);
 193 }
 194
 195 void
 196 get_cats(cat1, cat2)
 197         char *cat1, *cat2;
 198 {
 199         QE *qp;
 200         int i;
 201         const char *s;
 202
 203         downcase(cat1);
 204         downcase(cat2);
 205         for (qp = qlist.q_next; qp; qp = qp->q_next) {
 206                 s = next_cat(qp->q_text);
 207                 catone = cattwo = i = 0;
 208                 while (s) {
 209                         if (!rxp_compile(s))
 210                                 errx(1, "%s", rxperr);
 211                         i++;
 212                         if (rxp_match(cat1))
 213                                 catone = i;
 214                         if (rxp_match(cat2))
 215                                 cattwo = i;
 216                         s = next_cat(s);
 217                 }
 218                 if (catone && cattwo && catone != cattwo) {
 219                         if (!rxp_compile(qp->q_text))
 220                                 errx(1, "%s", rxperr);
 221                         get_file(rxp_expand());
 222                         return;
 223                 }
 224         }
 225         errx(1, "invalid categories");
 226 }
 227
 228 void
 229 quiz()
 230 {
 231         QE *qp;
 232         int i;
 233         size_t len;
 234         u_int guesses, rights, wrongs;
 235         int next;
 236         char *answer, *t, question[LINE_SZ];
 237         const char *s;
 238
 239         srandom(time(NULL));
 240         guesses = rights = wrongs = 0;
 241         for (;;) {
 242                 if (qsize == 0)
 243                         break;
 244                 next = random() % qsize;
 245                 qp = qlist.q_next;
 246                 for (i = 0; i < next; i++)
 247                         qp = qp->q_next;
 248                 while (qp && qp->q_answered)
 249                         qp = qp->q_next;
 250                 if (!qp) {
 251                         qsize = next;
 252                         continue;
 253                 }
 254                 if (tflag && random() % 100 > 20) {
 255                         /* repeat questions in tutorial mode */
 256                         while (qp && (!qp->q_asked || qp->q_answered))
 257                                 qp = qp->q_next;
 258                         if (!qp)
 259                                 continue;
 260                 }
 261                 s = qp->q_text;
 262                 for (i = 0; i < catone - 1; i++)
 263                         s = next_cat(s);
 264                 if (!rxp_compile(s))
 265                         errx(1, "%s", rxperr);
 266                 t = rxp_expand();
 267                 if (!t || *t == '\0') {
 268                         qp->q_answered = TRUE;
 269                         continue;
 270                 }
 271                 (void)strcpy(question, t);
 272                 s = qp->q_text;
 273                 for (i = 0; i < cattwo - 1; i++)
 274                         s = next_cat(s);
 275                 if (!rxp_compile(s))
 276                         errx(1, "%s", rxperr);
 277                 t = rxp_expand();
 278                 if (!t || *t == '\0') {
 279                         qp->q_answered = TRUE;
 280                         continue;
 281                 }
 282                 qp->q_asked = TRUE;
 283                 (void)printf("%s?\n", question);
 284                 for (;; ++guesses) {
 285                         if ((answer = fgetln(stdin, &len)) == NULL ||
 286                             answer[len - 1] != '\n') {
 287                                 score(rights, wrongs, guesses);
 288                                 exit(0);
 289                         }
 290                         answer[len - 1] = '\0';
 291                         downcase(answer);
 292                         if (rxp_match(answer)) {
 293                                 (void)printf("Right!\n");
 294                                 ++rights;
 295                                 qp->q_answered = TRUE;
 296                                 break;
 297                         }
 298                         if (*answer == '\0') {
 299                                 (void)printf("%s\n", t);
 300                                 ++wrongs;
 301                                 if (!tflag)
 302                                         qp->q_answered = TRUE;
 303                                 break;
 304                         }
 305                         (void)printf("What?\n");
 306                 }
 307         }
 308         score(rights, wrongs, guesses);
 309 }
 310
 311 const char *
 312 next_cat(s)
 313         const char *    s;
 314 {
 315         int esc;
 316
 317         esc = 0;
 318         for (;;)
 319                 switch (*s++) {
 320                 case '\0':
 321                         return (NULL);
 322                 case '\\':
 323                         esc = 1;
 324                         break;
 325                 case ':':
 326                         if (!esc)
 327                                 return (s);
 328                 default:
 329                         esc = 0;
 330                         break;
 331                 }
 332         /* NOTREACHED */
 333 }
 334
 335 char *
 336 appdstr(s, tp, len)
 337         char *s;
 338         const char *tp;
 339         size_t len;
 340 {
 341         char *mp;
 342         const char *sp;
 343         int ch;
 344         char *m;
 345
 346         if ((m = malloc(strlen(s) + len + 1)) == NULL)
 347                 errx(1, "malloc");
 348         for (mp = m, sp = s; (*mp++ = *sp++) != '\0'; )
 349                 ;
 350         --mp;
 351         if (*(mp - 1) == '\\')
 352                 --mp;
 353
 354         while ((ch = *mp++ = *tp++) && ch != '\n')
 355                 ;
 356         *mp = '\0';
 357
 358         free(s);
 359         return (m);
 360 }
 361
 362 void
 363 score(r, w, g)
 364         u_int r, w, g;
 365 {
 366         (void)printf("Rights %d, wrongs %d,", r, w);
 367         if (g)
 368                 (void)printf(" extra guesses %d,", g);
 369         (void)printf(" score %d%%\n", (r + w + g) ? r * 100 / (r + w + g) : 0);
 370 }
 371
 372 void
 373 downcase(p)
 374         char *p;
 375 {
 376         int ch;
 377
 378         for (; (ch = *p) != '\0'; ++p)
 379                 if (isascii(ch) && isupper(ch))
 380                         *p = tolower(ch);
 381 }
 382
 383 void
 384 usage()
 385 {
 386         (void)fprintf(stderr, "quiz [-t] [-i file] category1 category2\n");
 387         exit(1);
 388 }