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#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
bucket **symbol_table;
bucket *first_symbol;
bucket *last_symbol;
#if __STDC__
static int hash(char *name)
#else
static int hash(name)
char *name;
#endif
{
register char *s;
register int c, k;
assert(name != (char *) NULL && *name);
s = name;
k = *s;
while (c = *++s)
k = (31*k + c) & (TABLE_SIZE - 1);
return (k);
}
#if __STDC__
bucket *make_bucket(char *name)
#else
bucket *make_bucket(name)
char *name;
#endif
{
register bucket *bp;
assert(name != (char *) NULL);
bp = (bucket *) MALLOC(sizeof(bucket));
bp->link = 0;
bp->next = 0;
bp->name = MALLOC(strlen(name) + 1);
bp->tag = 0;
bp->value = UNDEFINED;
bp->index = 0;
bp->prec = 0;
bp-> class = UNKNOWN;
bp->assoc = TOKEN;
strcpy(bp->name, name);
return (bp);
}
#if __STDC__
bucket *lookup(char *name)
#else
bucket *lookup(name)
char *name;
#endif
{
register 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);
}
#if __STDC__
void create_symbol_table(void)
#else
void create_symbol_table()
#endif
{
register int i;
register bucket *bp;
symbol_table = (bucket **) MALLOC(TABLE_SIZE*sizeof(bucket *));
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;
}
#if __STDC__
void free_symbol_table(void)
#else
void free_symbol_table()
#endif
{
FREE(symbol_table);
symbol_table = 0;
}
#if __STDC__
void free_symbols(void)
#else
void free_symbols()
#endif
{
register bucket *p, *q;
for (p = first_symbol; p; p = q)
{
q = p->next;
FREE(p);
}
}
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