quiz/quiz.c

   1 /*      $NetBSD: quiz.c,v 1.25 2009/08/27 00:24:11 dholland 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 1.25 2009/08/27 00:24:11 dholland 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 unsigned qsize;
  66
  67 int      main(int, char *[]);
  68 static char *appdstr(char *, const char *, size_t);
  69 static void downcase(char *);
  70 static void get_cats(char *, char *);
  71 static void get_file(const char *);
  72 static const char *next_cat(const char *);
  73 static void quiz(void);
  74 static void score(unsigned, unsigned, unsigned);
  75 static void show_index(void);
  76 static 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 static 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 static 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 static 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 static void
 228 quiz()
 229 {
 230         QE *qp;
 231         int i;
 232         size_t len;
 233         unsigned 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 static 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 static 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 static void
 362 score(r, w, g)
 363         unsigned 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 static 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 static void
 383 usage()
 384 {
 385         (void)fprintf(stderr, "quiz [-t] [-i file] category1 category2\n");
 386         exit(1);
 387 }