4.4BSD/usr/src/usr.bin/lex/sym.c
/* sym - symbol table routines */
/*-
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Vern Paxson of Lawrence Berkeley Laboratory.
*
* The United States Government has rights in this work pursuant
* to contract no. DE-AC03-76SF00098 between the United States
* Department of Energy and the University of California.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static char sccsid[] = "@(#)sym.c 8.1 (Berkeley) 6/6/93";
#endif /* not lint */
#include "flexdef.h"
/* declare functions that have forward references */
int hashfunct PROTO((register char[], int));
struct hash_entry *ndtbl[NAME_TABLE_HASH_SIZE];
struct hash_entry *sctbl[START_COND_HASH_SIZE];
struct hash_entry *ccltab[CCL_HASH_SIZE];
struct hash_entry *findsym();
/* addsym - add symbol and definitions to symbol table
*
* synopsis
* char sym[], *str_def;
* int int_def;
* hash_table table;
* int table_size;
* 0 / -1 = addsym( sym, def, int_def, table, table_size );
*
* -1 is returned if the symbol already exists, and the change not made.
*/
int addsym( sym, str_def, int_def, table, table_size )
register char sym[];
char *str_def;
int int_def;
hash_table table;
int table_size;
{
int hash_val = hashfunct( sym, table_size );
register struct hash_entry *sym_entry = table[hash_val];
register struct hash_entry *new_entry;
register struct hash_entry *successor;
while ( sym_entry )
{
if ( ! strcmp( sym, sym_entry->name ) )
{ /* entry already exists */
return ( -1 );
}
sym_entry = sym_entry->next;
}
/* create new entry */
new_entry = (struct hash_entry *) malloc( sizeof( struct hash_entry ) );
if ( new_entry == NULL )
flexfatal( "symbol table memory allocation failed" );
if ( (successor = table[hash_val]) )
{
new_entry->next = successor;
successor->prev = new_entry;
}
else
new_entry->next = NULL;
new_entry->prev = NULL;
new_entry->name = sym;
new_entry->str_val = str_def;
new_entry->int_val = int_def;
table[hash_val] = new_entry;
return ( 0 );
}
/* cclinstal - save the text of a character class
*
* synopsis
* Char ccltxt[];
* int cclnum;
* cclinstal( ccltxt, cclnum );
*/
void cclinstal( ccltxt, cclnum )
Char ccltxt[];
int cclnum;
{
/* we don't bother checking the return status because we are not called
* unless the symbol is new
*/
Char *copy_unsigned_string();
(void) addsym( (char *) copy_unsigned_string( ccltxt ), (char *) 0, cclnum,
ccltab, CCL_HASH_SIZE );
}
/* ccllookup - lookup the number associated with character class text
*
* synopsis
* Char ccltxt[];
* int ccllookup, cclval;
* cclval/0 = ccllookup( ccltxt );
*/
int ccllookup( ccltxt )
Char ccltxt[];
{
return ( findsym( (char *) ccltxt, ccltab, CCL_HASH_SIZE )->int_val );
}
/* findsym - find symbol in symbol table
*
* synopsis
* char sym[];
* hash_table table;
* int table_size;
* struct hash_entry *sym_entry, *findsym();
* sym_entry = findsym( sym, table, table_size );
*/
struct hash_entry *findsym( sym, table, table_size )
register char sym[];
hash_table table;
int table_size;
{
register struct hash_entry *sym_entry = table[hashfunct( sym, table_size )];
static struct hash_entry empty_entry =
{
(struct hash_entry *) 0, (struct hash_entry *) 0, NULL, NULL, 0,
} ;
while ( sym_entry )
{
if ( ! strcmp( sym, sym_entry->name ) )
return ( sym_entry );
sym_entry = sym_entry->next;
}
return ( &empty_entry );
}
/* hashfunct - compute the hash value for "str" and hash size "hash_size"
*
* synopsis
* char str[];
* int hash_size, hash_val;
* hash_val = hashfunct( str, hash_size );
*/
int hashfunct( str, hash_size )
register char str[];
int hash_size;
{
register int hashval;
register int locstr;
hashval = 0;
locstr = 0;
while ( str[locstr] )
hashval = ((hashval << 1) + (unsigned char) str[locstr++]) % hash_size;
return ( hashval );
}
/* ndinstal - install a name definition
*
* synopsis
* char nd[];
* Char def[];
* ndinstal( nd, def );
*/
void ndinstal( nd, def )
char nd[];
Char def[];
{
char *copy_string();
Char *copy_unsigned_string();
if ( addsym( copy_string( nd ), (char *) copy_unsigned_string( def ), 0,
ndtbl, NAME_TABLE_HASH_SIZE ) )
synerr( "name defined twice" );
}
/* ndlookup - lookup a name definition
*
* synopsis
* char nd[], *def;
* char *ndlookup();
* def/NULL = ndlookup( nd );
*/
Char *ndlookup( nd )
char nd[];
{
return ( (Char *) findsym( nd, ndtbl, NAME_TABLE_HASH_SIZE )->str_val );
}
/* scinstal - make a start condition
*
* synopsis
* char str[];
* int xcluflg;
* scinstal( str, xcluflg );
*
* NOTE
* the start condition is Exclusive if xcluflg is true
*/
void scinstal( str, xcluflg )
char str[];
int xcluflg;
{
char *copy_string();
/* bit of a hack. We know how the default start-condition is
* declared, and don't put out a define for it, because it
* would come out as "#define 0 1"
*/
/* actually, this is no longer the case. The default start-condition
* is now called "INITIAL". But we keep the following for the sake
* of future robustness.
*/
if ( strcmp( str, "0" ) )
printf( "#define %s %d\n", str, lastsc );
if ( ++lastsc >= current_max_scs )
{
current_max_scs += MAX_SCS_INCREMENT;
++num_reallocs;
scset = reallocate_integer_array( scset, current_max_scs );
scbol = reallocate_integer_array( scbol, current_max_scs );
scxclu = reallocate_integer_array( scxclu, current_max_scs );
sceof = reallocate_integer_array( sceof, current_max_scs );
scname = reallocate_char_ptr_array( scname, current_max_scs );
actvsc = reallocate_integer_array( actvsc, current_max_scs );
}
scname[lastsc] = copy_string( str );
if ( addsym( scname[lastsc], (char *) 0, lastsc,
sctbl, START_COND_HASH_SIZE ) )
format_pinpoint_message( "start condition %s declared twice", str );
scset[lastsc] = mkstate( SYM_EPSILON );
scbol[lastsc] = mkstate( SYM_EPSILON );
scxclu[lastsc] = xcluflg;
sceof[lastsc] = false;
}
/* sclookup - lookup the number associated with a start condition
*
* synopsis
* char str[], scnum;
* int sclookup;
* scnum/0 = sclookup( str );
*/
int sclookup( str )
char str[];
{
return ( findsym( str, sctbl, START_COND_HASH_SIZE )->int_val );
}