1 /* sym - symbol table routines */
4 * Copyright (c) 1990 The Regents of the University of California.
7 * This code is derived from software contributed to Berkeley by
10 * The United States Government has rights in this work pursuant
11 * to contract no. DE-AC03-76SF00098 between the United States
12 * Department of Energy and the University of California.
14 * Redistribution and use in source and binary forms are permitted provided
15 * that: (1) source distributions retain this entire copyright notice and
16 * comment, and (2) distributions including binaries display the following
17 * acknowledgement: ``This product includes software developed by the
18 * University of California, Berkeley and its contributors'' in the
19 * documentation or other materials provided with the distribution and in
20 * all advertising materials mentioning features or use of this software.
21 * Neither the name of the University nor the names of its contributors may
22 * be used to endorse or promote products derived from this software without
23 * specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
25 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
26 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
29 /* $Header: /home/daffy/u0/vern/flex/RCS/sym.c,v 2.19 95/03/04 16:11:04 vern Exp $ */
30 /* $FreeBSD: src/usr.bin/lex/sym.c,v 1.5 1999/10/27 07:56:47 obrien Exp $ */
35 /* declare functions that have forward references */
37 int hashfunct PROTO((char[], int));
40 struct hash_entry *ndtbl[NAME_TABLE_HASH_SIZE];
41 struct hash_entry *sctbl[START_COND_HASH_SIZE];
42 struct hash_entry *ccltab[CCL_HASH_SIZE];
44 struct hash_entry *findsym();
47 /* addsym - add symbol and definitions to symbol table
49 * -1 is returned if the symbol already exists, and the change not made.
52 int addsym(char *sym, char *str_def, int int_def, hash_table table,
55 int hash_val = hashfunct( sym, table_size );
56 struct hash_entry *sym_entry = table[hash_val];
57 struct hash_entry *new_entry;
58 struct hash_entry *successor;
62 if ( ! strcmp( sym, sym_entry->name ) )
63 { /* entry already exists */
67 sym_entry = sym_entry->next;
70 /* create new entry */
71 new_entry = (struct hash_entry *)
72 flex_alloc( sizeof( struct hash_entry ) );
74 if ( new_entry == NULL )
75 flexfatal( _( "symbol table memory allocation failed" ) );
77 if ( (successor = table[hash_val]) != NULL )
79 new_entry->next = successor;
80 successor->prev = new_entry;
83 new_entry->next = NULL;
85 new_entry->prev = NULL;
86 new_entry->name = sym;
87 new_entry->str_val = str_def;
88 new_entry->int_val = int_def;
90 table[hash_val] = new_entry;
96 /* cclinstal - save the text of a character class */
98 void cclinstal(Char *ccltxt, int cclnum)
100 /* We don't bother checking the return status because we are not
101 * called unless the symbol is new.
103 Char *copy_unsigned_string();
105 (void) addsym( (char *) copy_unsigned_string( ccltxt ),
107 ccltab, CCL_HASH_SIZE );
111 /* ccllookup - lookup the number associated with character class text
113 * Returns 0 if there's no CCL associated with the text.
116 int ccllookup(Char *ccltxt)
118 return findsym( (char *) ccltxt, ccltab, CCL_HASH_SIZE )->int_val;
122 /* findsym - find symbol in symbol table */
124 struct hash_entry *findsym(char *sym, hash_table table, int table_size)
126 static struct hash_entry empty_entry =
131 struct hash_entry *sym_entry =
132 table[hashfunct( sym, table_size )];
136 if ( ! strcmp( sym, sym_entry->name ) )
138 sym_entry = sym_entry->next;
145 /* hashfunct - compute the hash value for "str" and hash size "hash_size" */
147 int hashfunct(char *str, int hash_size)
155 while ( str[locstr] )
157 hashval = (hashval << 1) + (unsigned char) str[locstr++];
158 hashval %= hash_size;
165 /* ndinstal - install a name definition */
167 void ndinstal(char *name, Char *definition)
170 Char *copy_unsigned_string();
172 if ( addsym( copy_string( name ),
173 (char *) copy_unsigned_string( definition ), 0,
174 ndtbl, NAME_TABLE_HASH_SIZE ) )
175 synerr( _( "name defined twice" ) );
179 /* ndlookup - lookup a name definition
181 * Returns a nil pointer if the name definition does not exist.
184 Char *ndlookup(char *nd)
186 return (Char *) findsym( nd, ndtbl, NAME_TABLE_HASH_SIZE )->str_val;
190 /* scextend - increase the maximum number of start conditions */
194 current_max_scs += MAX_SCS_INCREMENT;
198 scset = reallocate_integer_array( scset, current_max_scs );
199 scbol = reallocate_integer_array( scbol, current_max_scs );
200 scxclu = reallocate_integer_array( scxclu, current_max_scs );
201 sceof = reallocate_integer_array( sceof, current_max_scs );
202 scname = reallocate_char_ptr_array( scname, current_max_scs );
206 /* scinstal - make a start condition
209 * The start condition is "exclusive" if xcluflg is true.
212 void scinstal(char *str, int xcluflg)
216 /* Generate start condition definition, for use in BEGIN et al. */
217 action_define( str, lastsc );
219 if ( ++lastsc >= current_max_scs )
222 scname[lastsc] = copy_string( str );
224 if ( addsym( scname[lastsc], NULL, lastsc,
225 sctbl, START_COND_HASH_SIZE ) )
226 format_pinpoint_message(
227 _( "start condition %s declared twice" ),
230 scset[lastsc] = mkstate( SYM_EPSILON );
231 scbol[lastsc] = mkstate( SYM_EPSILON );
232 scxclu[lastsc] = xcluflg;
233 sceof[lastsc] = false;
237 /* sclookup - lookup the number associated with a start condition
239 * Returns 0 if no such start condition.
242 int sclookup(char *str)
244 return findsym( str, sctbl, START_COND_HASH_SIZE )->int_val;