4.3BSD - /usr/src/usr.bin/refer/thash.c

   1: #ifndef lint
   2: static char *sccsid = "@(#)thash.c	4.1 (Berkeley) 5/6/83";
   3: #endif
   4: 
   5: #include <stdio.h>
   6: #define MAXLINE 750
   7: 
   8: int nh 500;
   9: int saw[6000];
  10: char *comname "/usr/lib/eign";
  11: 
  12: main (argc,argv)
  13: char *argv[];
  14: {
  15: 
  16:     int i, z;
  17:     char *name;
  18: 
  19:     FILE *f;
  20: 
  21:     while (argc>1 && argv[1][0] == '-')
  22:     {
  23:         switch(argv[1][1])
  24:         {
  25:         case 'h':
  26:             nh = atoi(argv[1]+2);
  27:             break;
  28:         }
  29:         argc--;
  30:         argv++;
  31:     }
  32:     if (argc<=1)
  33:         dofile(stdin, "");
  34:     else
  35:         for(i=1; i<argc; i++)
  36:         {
  37:             f = fopen(name=argv[i], "r");
  38:             if (f==NULL)
  39:                 err("No file %s",name);
  40:             else
  41:                 dofile(f, name);
  42:         }
  43:     for(z=i=0; i<nh; i++)
  44:     {
  45:         if (saw[i]) z++;
  46:     }
  47:     printf("hashes %d used %d\n",nh,z);
  48: }
  49: 
  50: dofile(f, name)
  51: FILE *f;
  52: char *name;
  53: {
  54:     /* read file f & spit out keys & ptrs */
  55:     char line[MAXLINE], *s;
  56:     char key[20], *p;
  57:     int k 0;
  58:     int c, lim;
  59:     int alph 0;
  60:     int used 0;
  61:     long lp 0;
  62: 
  63:     while (fgets(line, MAXLINE, f))
  64:     {
  65:         k++;
  66:         used=alph=0;
  67:         lim = strlen(line);
  68:         p = key;
  69:         for(s=line; c= *s; s++)
  70:         {
  71:             if (isalpha(c) || isdigit(c))
  72:             {
  73:                 if (alph++ < 6)
  74:                     *p++ = c;
  75:             }
  76:             else
  77:             {
  78:                 *p = 0;
  79:                 if (outkey(p=key))
  80:                 {
  81:                     tkey(key,k);
  82:                     used=1;
  83:                 }
  84:                 alph=0;
  85:             }
  86:         }
  87:         lp += lim;
  88:     }
  89: }
  90: 
  91: outkey( ky)
  92: char *ky;
  93: {
  94:     int n;
  95:     n = strlen(ky);
  96:     if (n<3) return(0);
  97:     if (isdigit(ky[0]))
  98:         if (ky[0] != '1' || ky[1] != '9' || n!= 4) return(0);
  99:     return(1);
 100: }
 101: 
 102: hash (s)
 103: char *s;
 104: {
 105:     int c, n, q;
 106:     for(q=n=0; c= *s; s++)
 107:         n += (c*n + c << (n%4));
 108:     return(n);
 109: }
 110: 
 111: err (s, a)
 112: char *s;
 113: {
 114:     fprintf(stderr, "Error: ");
 115:     fprintf(stderr, s, a);
 116:     putc('\n', stderr);
 117: }
 118: 
 119: prefix(t, s)
 120: char *t, *s;
 121: {
 122:     int c, d;
 123:     while ( (c= *t++) == *s++)
 124:         if (c==0) return(1);
 125:     return(c==0 ? 1: 0);
 126: }
 127: 
 128: mindex(s, c)
 129: char *s;
 130: {
 131:     register char *p;
 132:     for( p=s; *p; p++)
 133:         if (*p ==c)
 134:             return(p);
 135:     return(0);
 136: }
 137: 
 138: tkey(s,nw)
 139: char *s;
 140: {
 141:     int x;
 142:     x = abs(hash(s)) % nh;
 143:     /* if (saw[x]) printf("%d %d\n", x, nw); */
 144:     saw[x]= nw;
 145: }
 146: 
 147: abs(n)
 148: {
 149:     return(n>0 ? n : -n);
 150: }

Defined functions

Defined variables

Defined macros