2 /* Copyright (C) 1989, 1990, 1991, 1992, 2002 Free Software Foundation, Inc.
3 Written by James Clark (jjc@jclark.com)
5 This file is part of groff.
7 groff is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 groff is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License along
18 with groff; see the file COPYING. If not, write to the Free Software
19 Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
25 const char **symbol::table = 0;
26 int symbol::table_used = 0;
27 int symbol::table_size = 0;
28 char *symbol::block = 0;
29 int symbol::block_size = 0;
31 const symbol NULL_SYMBOL;
32 const symbol EMPTY_SYMBOL("");
38 const int BLOCK_SIZE = 1024;
39 // the table will increase in size as necessary
40 // the size will be chosen from the following array
41 // add some more if you want
42 static const unsigned int table_sizes[] = {
43 101, 503, 1009, 2003, 3001, 4001, 5003, 10007, 20011, 40009, 80021,
44 160001, 500009, 1000003, 1500007, 2000003, 0
46 const double FULL_MAX = 0.3; // don't let the table get more than this full
48 static unsigned int hash_string(const char *p)
50 // compute a hash code; this assumes 32-bit unsigned ints
51 // see p436 of Compilers by Aho, Sethi & Ullman
52 // give special treatment to two-character names
53 unsigned int hc = 0, g;
59 for (; *p != 0; p++) {
62 if ((g = (hc & 0xf0000000)) == 0) {
72 // Tell compiler that a variable is intentionally unused.
73 inline void unused(void *) { }
75 symbol::symbol(const char *p, int how)
86 table_size = table_sizes[0];
87 table = (const char **)new char*[table_size];
88 for (int i = 0; i < table_size; i++)
92 unsigned int hc = hash_string(p);
94 for (pp = table + hc % table_size;
96 (pp == table ? pp = table + table_size - 1 : --pp))
97 if (strcmp(p, *pp) == 0) {
101 if (how == MUST_ALREADY_EXIST) {
105 if (table_used >= table_size - 1 || table_used >= table_size*FULL_MAX) {
106 const char **old_table = table;
107 unsigned int old_table_size = table_size;
109 for (i = 1; table_sizes[i] <= old_table_size; i++)
110 if (table_sizes[i] == 0)
111 fatal("too many symbols");
112 table_size = table_sizes[i];
114 table = (const char **)new char*[table_size];
115 for (i = 0; i < table_size; i++)
117 for (pp = old_table + old_table_size - 1;
120 symbol temp(*pp, 1); /* insert it into the new table */
124 for (pp = table + hc % table_size;
126 (pp == table ? pp = table + table_size - 1 : --pp))
130 if (how == DONT_STORE) {
134 int len = strlen(p)+1;
135 if (block == 0 || block_size < len) {
136 block_size = len > BLOCK_SIZE ? len : BLOCK_SIZE;
137 block = new char [block_size];
139 (void)strcpy(block, p);
146 symbol concat(symbol s1, symbol s2)
148 char *buf = new char [strlen(s1.contents()) + strlen(s2.contents()) + 1];
149 strcpy(buf, s1.contents());
150 strcat(buf, s2.contents());