freebsd-skq/contrib/byacc/symtab.c
bapt 913116490c Import byacc from invisible island, it brings us lots of compatibilities with
bison, keeping full compatibility with our previous yacc implementation.

Also bring the ability to create reentrant parser

This fix bin/140309 [1]

PR:		bin/140309 [1]
Submitted by:	Philippe Pepiot <ksh@philpep.org> [1]
Approved by:	des (mentor)
MFC after:	1 month
2012-05-21 13:31:26 +00:00

118 lines
1.8 KiB
C

/* $Id: symtab.c,v 1.9 2010/11/24 15:12:29 tom Exp $ */
#include "defs.h"
/* TABLE_SIZE is the number of entries in the symbol table. */
/* TABLE_SIZE must be a power of two. */
#define TABLE_SIZE 1024
static bucket **symbol_table = 0;
bucket *first_symbol;
bucket *last_symbol;
static int
hash(const char *name)
{
const char *s;
int c, k;
assert(name && *name);
s = name;
k = *s;
while ((c = *++s) != 0)
k = (31 * k + c) & (TABLE_SIZE - 1);
return (k);
}
bucket *
make_bucket(const char *name)
{
bucket *bp;
assert(name != 0);
bp = (bucket *)MALLOC(sizeof(bucket));
NO_SPACE(bp);
bp->link = 0;
bp->next = 0;
bp->name = MALLOC(strlen(name) + 1);
NO_SPACE(bp->name);
bp->tag = 0;
bp->value = UNDEFINED;
bp->index = 0;
bp->prec = 0;
bp->class = UNKNOWN;
bp->assoc = TOKEN;
strcpy(bp->name, name);
return (bp);
}
bucket *
lookup(const char *name)
{
bucket *bp, **bpp;
bpp = symbol_table + hash(name);
bp = *bpp;
while (bp)
{
if (strcmp(name, bp->name) == 0)
return (bp);
bpp = &bp->link;
bp = *bpp;
}
*bpp = bp = make_bucket(name);
last_symbol->next = bp;
last_symbol = bp;
return (bp);
}
void
create_symbol_table(void)
{
int i;
bucket *bp;
symbol_table = (bucket **)MALLOC(TABLE_SIZE * sizeof(bucket *));
NO_SPACE(symbol_table);
for (i = 0; i < TABLE_SIZE; i++)
symbol_table[i] = 0;
bp = make_bucket("error");
bp->index = 1;
bp->class = TERM;
first_symbol = bp;
last_symbol = bp;
symbol_table[hash("error")] = bp;
}
void
free_symbol_table(void)
{
FREE(symbol_table);
symbol_table = 0;
}
void
free_symbols(void)
{
bucket *p, *q;
for (p = first_symbol; p; p = q)
{
q = p->next;
FREE(p);
}
}