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());