larn/fortune.c

   1 /* fortune.c             Larn is copyrighted 1986 by Noah Morgan. */
   2 #include <sys/types.h>
   3 #include <sys/stat.h>
   4 #include <fcntl.h>
   5
   6 #include "header.h"
   7 /*
   8  *      function to return a random fortune from the fortune file
   9  */
  10 static char *base=0;    /* pointer to the fortune text */
  11 static char **flines=0; /* array of pointers to each fortune */
  12 static int fd=0;                /* true if we have load the fortune info */
  13 static int nlines=0;    /* # lines in fortune database */
  14
  15 char *fortune(file)
  16         char *file;
  17         {
  18         register char *p;
  19         register int lines,tmp;
  20         struct stat stat;
  21         char *malloc();
  22         if (fd==0)
  23                 {
  24                 if ((fd=open(file,O_RDONLY)) < 0)       /* open the file */
  25                         return(0); /* can't find file */
  26
  27         /* find out how big fortune file is and get memory for it */
  28                 stat.st_size = 16384;
  29                 if ((fstat(fd,&stat) < 0) || ((base=malloc(1+stat.st_size)) == 0))
  30                         {
  31                         close(fd); fd= -1; free((char*)base); return(0);        /* can't stat file */
  32                         }
  33
  34         /* read in the entire fortune file */
  35                 if (read(fd,base,stat.st_size) != stat.st_size)
  36                         {
  37                         close(fd); fd= -1; free((char*)base); return(0);        /* can't read file */
  38                         }
  39                 close(fd);  base[stat.st_size]=0;       /* final NULL termination */
  40
  41         /* count up all the lines (and NULL terminate) to know memory needs */
  42                 for (p=base,lines=0; p<base+stat.st_size; p++) /* count lines */
  43                         if (*p == '\n') *p=0,lines++;
  44                 nlines = lines;
  45
  46         /* get memory for array of pointers to each fortune */
  47                 if ((flines=(char**)malloc(nlines*sizeof(char*))) == 0)
  48                         {
  49                         free((char*)base); fd= -1; return(0); /* malloc() failure */
  50                         }
  51
  52         /* now assign each pointer to a line */
  53                 for (p=base,tmp=0; tmp<nlines; tmp++)
  54                         {
  55                         flines[tmp]=p;  while (*p++); /* advance to next line */
  56                         }
  57                 }
  58
  59         if (fd > 2)     /* if we have a database to look at */
  60                 return(flines[rund((nlines<=0)?1:nlines)]);
  61         else
  62                 return(0);
  63         }