#include <grammar.h>
+#include <first.h>
+#include <item.h>
+#ifdef DEBUG
+#include <stdio.h>
+#endif
-typedef struct
-{
- symbol_t* left;
- rule_t* right;
- GList* dot;
-} item_t;
-
-item_t* item_new (symbol_t* left, rule_t* right)
+item_t* item_new (symbol_t* left, rule_t* right, symbol_t* lookahead)
{
item_t* item;
item = g_malloc (sizeof (item_t));
item->left = left;
item->right = right;
item->dot = grammar_get_rule (right);
+ item->lookahead = lookahead;
return item;
}
{
item_t* newitem;
int n;
- newitem = item_new (symbol_copy (item->left), rule_copy (item->right));
+ newitem = item_new (symbol_copy (item->left), rule_copy (item->right),
+ symbol_copy (item->lookahead));
n = g_list_position (grammar_get_rule (item->right), item->dot);
newitem->dot = g_list_nth (grammar_get_rule (newitem->right), n);
return newitem;
return c;
if ((c = rule_cmp (a->right, b->right)) != 0)
return c;
+ if ((c = symbol_cmp (a->lookahead, b->lookahead)) != 0)
+ return c;
na = g_list_position (grammar_get_rule (a->right), a->dot);
nb = g_list_position (grammar_get_rule (b->right), b->dot);
if (na < nb)
guint hash;
item = (item_t*) data;
hash = rule_hash (item->right) * 37 + symbol_hash (item->left);
+ hash = hash * 37 + symbol_hash (item->lookahead);
return hash;
}
{
g_free (item->left);
rule_delete (item->right);
+ g_free (item->lookahead);
g_free (item);
}
+#ifdef DEBUG
+void item_print (item_t* item)
+{
+ GList* l;
+ fprintf (stdout, "%s -> ", g_quark_to_string (item->left->value));
+ l = grammar_get_rule (item->right);
+ while (l != NULL)
+ {
+ symbol_t* symbol;
+ symbol = (symbol_t*) l->data;
+ if (l == item->dot)
+ {
+ fprintf (stdout, ".");
+ }
+ fprintf (stdout, " %s ", g_quark_to_string (symbol->value));
+ l = g_list_next (l);
+ }
+ if (item->dot == NULL)
+ {
+ fprintf (stdout, ".");
+ }
+ fprintf (stdout, ", %s\n", g_quark_to_string (item->lookahead->value));
+}
+#endif
+
GHashTable* item_set_new ()
{
return g_hash_table_new_full (item_hash, item_equal, item_delete, NULL);
return FALSE;
}
-gboolean item_set_find (gpointer key, gpointer val, gpointer data)
+static void put_key_on_list (gpointer key, gpointer val, gpointer data)
{
- return !g_hash_table_lookup_extended (data, key, NULL, NULL);
+ GList** l;
+ l = (GList**) data;
+ *l = g_list_prepend (*l, key);
}
gboolean item_set_equal (gconstpointer a, gconstpointer b)
{
+ GList* l;
+ gboolean equal;
if (g_hash_table_size (a) != g_hash_table_size (b))
return FALSE;
- return (g_hash_table_find (a, item_set_find, b) == NULL);
+ l = NULL;
+ g_hash_table_foreach (a, put_key_on_list, (gpointer) &l);
+ equal = TRUE;
+ while (l != NULL && equal == TRUE)
+ {
+ equal = g_hash_table_lookup_extended (b, l->data, NULL, NULL);
+ l = g_list_next (l);
+ }
+ g_list_free (l);
+ return equal;
}
void hash_item (gpointer key, gpointer val, gpointer data)
return newitem_set;
}
+#ifdef DEBUG
+void item_set_print_each (gpointer key, gpointer val, gpointer data)
+{
+ item_print (key);
+}
+
+void item_set_print (GHashTable* item_set)
+{
+ g_hash_table_foreach (item_set, item_set_print_each, NULL);
+}
+#endif
+
+rule_t* rule_new_item (item_t* item)
+{
+
+ rule_t* rule;
+ GList* l;
+ rule = rule_new ();
+ l = g_list_next (item->dot);
+ while (l != NULL)
+ {
+ rule_append (rule, symbol_copy (l->data));
+ l = g_list_next (l);
+ }
+ rule_append (rule, symbol_copy (item->lookahead));
+ return rule;
+
+}
+
void item_set_closure_step (GHashTable* item_set, Grammar* grammar,
- item_t* item)
+ GHashTable* first, item_t* item)
{
if (item->dot != NULL)
{
if (symbol->terminal == FALSE)
{
GList* rules;
+ GList* terminals;
+ rule_t* rule;
+ rule = rule_new_item (item);
+ terminals = first_rule (first, rule);
+ rule_delete (rule);
rules = grammar_get_rules (grammar, symbol);
while (rules != NULL)
{
- rule_t* rule;
- item_t* newitem;
- rule = rule_copy (rules->data);
- newitem = item_new (symbol_copy (symbol), rule);
- if (!item_set_add (item_set, newitem))
- item_delete (newitem);
+ GList* lookahead;
+ lookahead = terminals;
+ while (lookahead != NULL)
+ {
+ rule_t* rule;
+ item_t* newitem;
+ rule = rule_copy (rules->data);
+ newitem = item_new (symbol_copy (symbol), rule,
+ symbol_copy (lookahead->data));
+ if (!item_set_add (item_set, newitem))
+ item_delete (newitem);
+ lookahead = g_list_next (lookahead);
+ }
rules = g_list_next (rules);
}
+ g_list_free (terminals);
}
}
}
-void put_key_on_list (gpointer key, gpointer val, gpointer data)
-{
- GList** l;
- l = (GList**) data;
- *l = g_list_prepend (*l, key);
-}
-
-GHashTable* item_set_closure (GHashTable* item_set, Grammar* grammar)
+GHashTable* item_set_closure (GHashTable* item_set, Grammar* grammar,
+ GHashTable* first)
{
int size;
int last_size;
g_hash_table_foreach (item_set, put_key_on_list, &l);
while (l != NULL)
{
- item_set_closure_step (item_set, grammar, l->data);
+ item_set_closure_step (item_set, grammar, first, l->data);
l = g_list_next (l);
}
g_list_free (l);
}
GHashTable* item_set_goto (GHashTable* item_set, Grammar* grammar,
- symbol_t* symbol)
+ GHashTable* first, symbol_t* symbol)
{
GList* l;
GHashTable* newitem_set;
}
l = g_list_next (l);
}
- return item_set_closure (newitem_set, grammar);
+ return item_set_closure (newitem_set, grammar, first);
}
return state;
}
+#ifdef DEBUG
+void item_collection_print_each (gpointer key, gpointer val, gpointer data)
+{
+ GHashTable* item_set;
+ state_t* state;
+ item_set = (GHashTable*) key;
+ state = (state_t*) val;
+ fprintf (stdout, "Item %d:\n", state->code);
+ item_set_print (item_set);
+ fprintf (stdout, "\n");
+}
+
+void item_set_print_goto (gpointer key, gpointer val, gpointer data)
+{
+ symbol_t* symbol;
+ gint code;
+ state_t* state;
+ symbol = (symbol_t*) key;
+ code = GPOINTER_TO_INT (val);
+ state = (state_t*) data;
+ fprintf (stdout, "GOTO (%d, %s) =\t %d\n", state->code,
+ g_quark_to_string (symbol->value), code);
+}
+
+void item_collection_print_goto (gpointer key, gpointer val, gpointer data)
+{
+ state_t* state;
+ state = (state_t*) val;
+ g_hash_table_foreach (state->symbols, item_set_print_goto, state);
+ fprintf (stdout, "\n");
+}
+
+void item_collection_print (GHashTable* collection)
+{
+ g_hash_table_foreach (collection, item_collection_print_each, NULL);
+ g_hash_table_foreach (collection, item_collection_print_goto, NULL);
+}
+#endif
+
GHashTable* item_collection_goto (GHashTable* collection, Grammar* grammar,
- GHashTable* item_set, symbol_t* symbol)
+ GHashTable* first, GHashTable* item_set,
+ symbol_t* symbol)
{
state_t* state;
state_t* goto_state;
{
return NULL;
}
- goto_item_set = item_set_goto (item_set, grammar, symbol);
+ goto_item_set = item_set_goto (item_set, grammar, first, symbol);
if (!item_collection_add (collection, goto_item_set))
return_item_set = NULL;
else
return return_item_set;
}
-void item_set_collection (Grammar* grammar, symbol_t* start)
+GHashTable* item_set_collection (Grammar* grammar, GHashTable* first,
+ symbol_t* start)
{
GHashTable* collection;
GHashTable* item_set;
GList* new_item_sets;
rule = rule_new ();
rule_append (rule, symbol_copy (start));
- item = item_new (symbol_new (FALSE, -1), rule);
+ item = item_new (symbol_new (FALSE, -1), rule, symbol_new (TRUE, 0));
item_set = item_set_new ();
item_set_add (item_set, item);
- item_set_closure (item_set, grammar);
+ item_set_closure (item_set, grammar, first);
collection = g_hash_table_new_full (item_set_hash, item_set_equal,
g_hash_table_destroy, NULL);
item_collection_add (collection, item_set);
{
symbol = (symbol_t*) item->dot->data;
if ((new_item_set =
- item_collection_goto (collection, grammar,
+ item_collection_goto (collection, grammar, first,
next_item_set, symbol)) != NULL)
{
g_list_append (new_item_sets, new_item_set);
new_item_sets = g_list_next (new_item_sets);
}
g_list_free (new_item_sets);
+#ifdef DEBUG
+ item_collection_print (collection);
+#endif
+ return collection;
}
projects / cascardo / grammar.git / blobdiff