diff options
Diffstat (limited to 'usr.bin/yacc/symtab.c')
-rw-r--r-- | usr.bin/yacc/symtab.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/usr.bin/yacc/symtab.c b/usr.bin/yacc/symtab.c new file mode 100644 index 0000000..ffb8127 --- /dev/null +++ b/usr.bin/yacc/symtab.c @@ -0,0 +1,162 @@ +/* + * Copyright (c) 1989 The Regents of the University of California. + * All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Robert Paul Corbett. + * + * 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. + * 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. + */ + +#if 0 +#ifndef lint +static char sccsid[] = "@(#)symtab.c 5.3 (Berkeley) 6/1/90"; +#endif +#endif + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <stdlib.h> +#include <string.h> +#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 int hash(const char *); + +bucket **symbol_table; +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)) + k = (31*k + c) & (TABLE_SIZE - 1); + + return (k); +} + + +bucket * +make_bucket(const char *name) +{ + bucket *bp; + + assert(name); + bp = malloc(sizeof(bucket)); + if (bp == 0) no_space(); + bp->link = 0; + bp->next = 0; + bp->name = malloc(strlen(name) + 1); + if (bp->name == 0) no_space(); + bp->tag = 0; + bp->value = UNDEFINED; + bp->index = 0; + bp->prec = 0; + bp-> class = UNKNOWN; + bp->assoc = TOKEN; + + if (bp->name == 0) no_space(); + strcpy(bp->name, name); + + return (bp); +} + + +bucket * +lookup(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 = malloc(TABLE_SIZE*sizeof(bucket *)); + if (symbol_table == 0) no_space(); + 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); + } +} |