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/* Copyright (C) 2004 Tresys Technology, LLC
* see file 'COPYING' for use and warranty information */
/*
* Author: jtang@tresys.com
*/
/* A simple symbol table implemented as a linked list. Nothing to see
* here, carry on.
*/
#include <stdlib.h>
#include <string.h>
#include "symtable.h"
#include "util.h"
static llist_t *symtable = NULL;
/* Retrieves a symbol from the symbol table. If it does not exist
return NULL. */
symbol_t *get_symbol (const char * const symbol_name) {
llist_node_t *node_ptr;
if (symtable == NULL) {
return NULL;
}
node_ptr = symtable->head;
while (node_ptr != NULL) {
symbol_t *sym = (symbol_t *) node_ptr->data;
if (sym != NULL && strcmp (sym->name, symbol_name) == 0) {
return sym;
}
node_ptr = node_ptr->next;
}
return NULL;
}
/* Adds a symbol to the symbol table without checking for duplicates.
Afterwards returns a pointer to that symbol. */
symbol_t *new_symbol (char * const symbol_name) {
symbol_t *sym;
if ((sym = malloc (sizeof (*sym))) == NULL) {
return NULL;
}
if ((sym->name = strdup (symbol_name)) == NULL) {
return NULL;
}
sym->value = ll_new ();
if (symtable == NULL) {
if ((symtable = ll_new ()) == NULL) {
return NULL;
}
}
(void) ll_append_data (symtable, sym);
return sym;
}
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