static int rdp_check_nullable(void * base)
{
int bad = 0;
rdp_data * temp =(rdp_data *) symbol_next_symbol_in_scope(base);
set_ work = SET_NULL;
while (temp != NULL)
{
if (temp->contains_null &&(temp->kind != K_CODE))
{
set_assign_set(& work, & temp->first);
set_intersect_set(& work, & temp->follow);
if (set_cardinality(& work)!= 0)
{
text_message(TEXT_ERROR, "LL(1) violation - rule\n %s ::= ", temp->id);
rdp_print_sub_item(temp, 1);
text_printf(".\n contains null but first and follow sets both include: ");
set_print_set(& work, rdp_token_string, 78);
text_printf("\n");
temp->ll1_violation = 1;
bad = 1;
}
}
temp =(rdp_data *) symbol_next_symbol_in_scope(temp);
}
return bad;
}
/* scan a sequence production for follow set changes */
static void rdp_follow_sequence(rdp_data * prod)
{
rdp_list * check = prod->list; /* pointer to sequence list */
while (check != NULL) /* scan entire sequence and add to follow sets */
{
rdp_list * following = check; /* temporary to look at followers */
unsigned old_cardinality = check->production->follow_cardinality;
do /* scan up list adding first sets of trailing productions */
{
following = following->next;
if (following == NULL) /* We hit end of sequence */
set_unite_set(& check->production->follow, & prod->follow);
else
set_unite_set(& check->production->follow, & following->production->first);
}
while (following != NULL && following->production->contains_null);
/* Update cardinality changed flag */
rdp_follow_changed |=((check->production->follow_cardinality =
set_cardinality(& check->production->follow)
)!= old_cardinality);
check = check->next; /* step to next item in sequence */
}
}
static int rdp_check_disjoint(void * base)
{
int bad = 0;
set_ work = SET_NULL;
rdp_data * temp =(rdp_data *) symbol_next_symbol_in_scope(base);
while (temp != NULL)
{
if (set_includes_element(& rdp_production_set, temp->kind)&& temp->kind != K_SEQUENCE)
{
rdp_list * left = temp->list;
while (left != NULL)
{
rdp_list * right = left->next;
while (right != NULL)
{
/* First check for disjoint on epsilon */
if (left->production->contains_null && right->production->contains_null)
{
text_message(TEXT_ERROR, "LL(1) violation - rule \'%s\'\n", temp->id);
text_printf(" productions %s ::= ", left->production->id);
rdp_print_sub_item(left->production, 1);
text_printf(".\n and %s ::= ", right->production->id);
rdp_print_sub_item(right->production, 1);
text_printf(".\n are both nullable \n");
left->production->ll1_violation = 1;
right->production->ll1_violation = 1;
bad = 1;
}
set_assign_set(& work, & left->production->first);
set_intersect_set(& work, & right->production->first);
if (set_cardinality(& work)!= 0)
{
text_message(TEXT_ERROR, "LL(1) violation - rule \'%s\'\n", temp->id);
text_printf(" productions %s ::= ", left->production->id);
rdp_print_sub_item(left->production, 1);
text_printf(".\n and %s ::= ", right->production->id);
rdp_print_sub_item(right->production, 1);
text_printf(".\n share these start tokens: ");
set_print_set(& work, rdp_token_string, 78);
text_printf("\n");
left->production->ll1_violation = 1;
right->production->ll1_violation = 1;
bad = 1;
}
right = right->next;
}
left = left->next;
}
}
temp =(rdp_data *) symbol_next_symbol_in_scope(temp);
}
return bad;
}
/*
* db_seq_cardinality() - This function returns only the number of non-null
* elements in the sequence.
* return : number of non-null elements in the sequence
* set(in): sequence descriptor
*/
int
db_seq_cardinality (DB_SET * set)
{
int retval;
CHECK_CONNECT_MINUSONE ();
CHECK_1ARG_MINUSONE (set);
retval = (set_cardinality (set));
return (retval);
}
/*
* db_col_cardinality() - This function returns the number of elements in the
* collection that have non-NULL values.
* return: the cardinality of the collection
* col(in): collection
*
* note : This is different than db_col_size which returns the total
* number of elements in the collection, including those with NULL
* values. Use of db_col_cardinality is discouraged since it is
* almost always the case that the API programmer really should be
* using db_col_size.
*/
int
db_col_cardinality (DB_COLLECTION * col)
{
int card;
CHECK_CONNECT_MINUSONE ();
CHECK_1ARG_MINUSONE (col);
card = set_cardinality (col);
return card;
}
static void rdp_update_follow_sets(void * base)
{
rdp_data * temp =(rdp_data *) symbol_next_symbol_in_scope(base);
while (temp != NULL)
{
if (temp->kind == K_LIST && temp->hi != 1 && temp->supplementary_token == NULL)
{
set_unite_set(& temp->follow, & temp->first);
temp->follow_cardinality = set_cardinality(& temp->follow);
}
temp =(rdp_data *) symbol_next_symbol_in_scope(temp);
}
}
/* scan an alternate for follow set changes */
static void rdp_follow_alternate(rdp_data * prod)
{
rdp_list * check = prod->list; /* pointer to alternate list */
while (check != NULL)
{
unsigned old_cardinality = check->production->follow_cardinality;
set_unite_set(& check->production->follow, & prod->follow);
rdp_follow_changed |=((check->production->follow_cardinality =
set_cardinality(& check->production->follow)
)!= old_cardinality);
check = check->next;
}
}
static void rdp_first(rdp_data * prod)
{
if (prod->in_use) /* something has gone wrong */
{
text_message(TEXT_ERROR, "LL(1) violation - rule \'%s\' is left recursive\n", prod->id); /* and return */
prod->ll1_violation = 1;
return;
}
if (!prod->first_done) /* something to do */
{
rdp_list * list = prod->list; /* set up alternates pointer */
prod->in_use = 1; /* mark this production as being processed */
if (prod->kind == K_SEQUENCE) /* sequences are treated differently */
{
prod->contains_null = 1; /* set up list flag */
while (list != NULL && prod->contains_null) /* scan until non-empty alternate is found */
{
if (!list->production->first_done) /* do first */
rdp_first(list->production);
set_unite_set(& prod->first, & list->production->first); /* add alternate first set to production first set */
prod->contains_null = list->production->contains_null; /* set contains_null flag */
list = list->next;
}
}
else
while (list != NULL) /* scan all alternates */
{
if (!list->production->first_done) /* do first */
rdp_first(list->production);
set_unite_set(& prod->first, & list->production->first); /* add alternate first set to production first set */
prod->contains_null |= list->production->contains_null; /* OR in contains_null flag */
list = list->next;
}
prod->in_use = 0; /* production is no longer in use */
prod->first_done = 1; /* first set is now complete */
/* and set cardinality */
prod->first_cardinality = set_cardinality(& prod->first);
}
}
int scan_test_set(const char * production, set_ * valid, set_ * stop)
{
if (!set_includes_element(valid, SCAN_CAST->token))
{
if (stop != NULL)
{
if (production != NULL)
text_message(TEXT_ERROR_ECHO, "In rule \'%s\', scanned ", production);
else
text_message(TEXT_ERROR_ECHO, "Scanned ");
set_print_element(SCAN_CAST->token, scan_token_names);
text_printf(" whilst expecting %s", set_cardinality(valid)== 1 ? "": "one of ");
set_print_set(valid, scan_token_names, 60);
text_printf("\n");
scan_skip(stop);
}
return 0;
}
else
return 1;
}
