hashnode
ht_lookup_with_hash (hash_table *table, const unsigned char *str,
size_t len, unsigned int hash,
enum ht_lookup_option insert)
{
unsigned int hash2;
unsigned int index;
size_t sizemask;
hashnode node;
sizemask = table->nslots - 1;
index = hash & sizemask;
table->searches++;
node = table->entries[index];
if (node != NULL)
{
if (node->hash_value == hash
&& HT_LEN (node) == (unsigned int) len
&& !memcmp (HT_STR (node), str, len))
{
if (insert == HT_ALLOCED)
/* The string we search for was placed at the end of the
obstack. Release it. */
obstack_free (&table->stack, (void *) str);
return node;
}
/* hash2 must be odd, so we're guaranteed to visit every possible
location in the table during rehashing. */
hash2 = ((hash * 17) & sizemask) | 1;
for (;;)
{
table->collisions++;
index = (index + hash2) & sizemask;
node = table->entries[index];
if (node == NULL)
break;
if (node->hash_value == hash
&& HT_LEN (node) == (unsigned int) len
&& !memcmp (HT_STR (node), str, len))
{
if (insert == HT_ALLOCED)
/* The string we search for was placed at the end of the
obstack. Release it. */
obstack_free (&table->stack, (void *) str);
return node;
}
}
}
if (insert == HT_NO_INSERT)
return NULL;
node = (*table->alloc_node) (table);
table->entries[index] = node;
HT_LEN (node) = (unsigned int) len;
node->hash_value = hash;
if (insert == HT_ALLOC)
HT_STR (node) = (const unsigned char *) obstack_copy0 (&table->stack,
str, len);
else
HT_STR (node) = str;
if (++table->nelements * 4 >= table->nslots * 3)
/* Must expand the string table. */
ht_expand (table);
return node;
}
hashnode
ht_lookup_with_hash (cpp_hash_table *table, const unsigned char *str,
size_t len, unsigned int hash,
enum ht_lookup_option insert)
{
unsigned int hash2;
unsigned int index;
unsigned int deleted_index = table->nslots;
size_t sizemask;
hashnode node;
sizemask = table->nslots - 1;
index = hash & sizemask;
table->searches++;
node = table->entries[index];
if (node != NULL)
{
if (node == DELETED)
deleted_index = index;
else if (node->hash_value == hash
&& HT_LEN (node) == (unsigned int) len
&& !memcmp (HT_STR (node), str, len))
return node;
/* hash2 must be odd, so we're guaranteed to visit every possible
location in the table during rehashing. */
hash2 = ((hash * 17) & sizemask) | 1;
for (;;)
{
table->collisions++;
index = (index + hash2) & sizemask;
node = table->entries[index];
if (node == NULL)
break;
if (node == DELETED)
{
if (deleted_index != table->nslots)
deleted_index = index;
}
else if (node->hash_value == hash
&& HT_LEN (node) == (unsigned int) len
&& !memcmp (HT_STR (node), str, len))
return node;
}
}
if (insert == HT_NO_INSERT)
return NULL;
/* We prefer to overwrite the first deleted slot we saw. */
if (deleted_index != table->nslots)
index = deleted_index;
node = (*table->alloc_node) (table);
table->entries[index] = node;
HT_LEN (node) = (unsigned int) len;
node->hash_value = hash;
if (table->alloc_subobject)
{
char *chars = (char *) table->alloc_subobject (len + 1);
memcpy (chars, str, len);
chars[len] = '\0';
HT_STR (node) = (const unsigned char *) chars;
}
else
HT_STR (node) = (const unsigned char *) obstack_copy0 (&table->stack,
str, len);
if (++table->nelements * 4 >= table->nslots * 3)
/* Must expand the string table. */
ht_expand (table);
return node;
}