gnu/dist/groff/src/libs/libgroff/ptable.cpp

   1 /*      $NetBSD$        */
   2
   3 /* Copyright (C) 1989, 1990, 1991, 1992 Free Software Foundation, Inc.
   4      Written by James Clark (jjc@jclark.com)
   5
   6 This file is part of groff.
   7
   8 groff is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 2, or (at your option) any later
  11 version.
  12
  13 groff is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License along
  19 with groff; see the file COPYING.  If not, write to the Free Software
  20 Foundation, 51 Franklin St - Fifth Floor, Boston, MA 02110-1301, USA. */
  21
  22 #include "ptable.h"
  23 #include "errarg.h"
  24 #include "error.h"
  25
  26 unsigned long hash_string(const char *s)
  27 {
  28   assert(s != 0);
  29   unsigned long h = 0, g;
  30   while (*s != 0) {
  31     h <<= 4;
  32     h += *s++;
  33     if ((g = h & 0xf0000000) != 0) {
  34       h ^= g >> 24;
  35       h ^= g;
  36     }
  37   }
  38   return h;
  39 }
  40
  41 static const unsigned table_sizes[] = {
  42 101, 503, 1009, 2003, 3001, 4001, 5003, 10007, 20011, 40009,
  43 80021, 160001, 500009, 1000003, 2000003, 4000037, 8000009,
  44 16000057, 32000011, 64000031, 128000003, 0
  45 };
  46
  47 unsigned next_ptable_size(unsigned n)
  48 {
  49   const unsigned *p;
  50   for (p = table_sizes; *p <= n; p++)
  51     if (*p == 0)
  52       fatal("cannot expand table");
  53   return *p;
  54 }