git-svn-id: http://svn.openzap.org/svn/openzap/trunk@205 a93c3328-9c30-0410-af19-c9cd2b2d52af
This commit is contained in:
Anthony Minessale
2007-06-04 14:53:12 +00:00
parent d8ab108f0b
commit 68d431bab1
33 changed files with 1205 additions and 833 deletions

View File

@@ -8,18 +8,18 @@
#include <math.h>
/*
Credit for primes table: Aaron Krowne
http://br.endernet.org/~akrowne/
http://planetmath.org/encyclopedia/GoodHashTablePrimes.html
Credit for primes table: Aaron Krowne
http://br.endernet.org/~akrowne/
http://planetmath.org/encyclopedia/GoodHashTablePrimes.html
*/
static const unsigned int primes[] = {
53, 97, 193, 389,
769, 1543, 3079, 6151,
12289, 24593, 49157, 98317,
196613, 393241, 786433, 1572869,
3145739, 6291469, 12582917, 25165843,
50331653, 100663319, 201326611, 402653189,
805306457, 1610612741
53, 97, 193, 389,
769, 1543, 3079, 6151,
12289, 24593, 49157, 98317,
196613, 393241, 786433, 1572869,
3145739, 6291469, 12582917, 25165843,
50331653, 100663319, 201326611, 402653189,
805306457, 1610612741
};
const unsigned int prime_table_length = sizeof(primes)/sizeof(primes[0]);
const float max_load_factor = 0.65f;
@@ -81,45 +81,45 @@ hashtable_expand(struct hashtable *h)
newtable = (struct entry **)malloc(sizeof(struct entry*) * newsize);
if (NULL != newtable)
{
memset(newtable, 0, newsize * sizeof(struct entry *));
/* This algorithm is not 'stable'. ie. it reverses the list
* when it transfers entries between the tables */
for (i = 0; i < h->tablelength; i++) {
while (NULL != (e = h->table[i])) {
h->table[i] = e->next;
index = indexFor(newsize,e->h);
e->next = newtable[index];
newtable[index] = e;
}
}
free(h->table);
h->table = newtable;
}
{
memset(newtable, 0, newsize * sizeof(struct entry *));
/* This algorithm is not 'stable'. ie. it reverses the list
* when it transfers entries between the tables */
for (i = 0; i < h->tablelength; i++) {
while (NULL != (e = h->table[i])) {
h->table[i] = e->next;
index = indexFor(newsize,e->h);
e->next = newtable[index];
newtable[index] = e;
}
}
free(h->table);
h->table = newtable;
}
/* Plan B: realloc instead */
else
{
newtable = (struct entry **)
realloc(h->table, newsize * sizeof(struct entry *));
if (NULL == newtable) { (h->primeindex)--; return 0; }
h->table = newtable;
memset(newtable[h->tablelength], 0, newsize - h->tablelength);
for (i = 0; i < h->tablelength; i++) {
for (pE = &(newtable[i]), e = *pE; e != NULL; e = *pE) {
index = indexFor(newsize,e->h);
if (index == i)
{
pE = &(e->next);
}
else
{
*pE = e->next;
e->next = newtable[index];
newtable[index] = e;
}
}
}
}
{
newtable = (struct entry **)
realloc(h->table, newsize * sizeof(struct entry *));
if (NULL == newtable) { (h->primeindex)--; return 0; }
h->table = newtable;
memset(newtable[h->tablelength], 0, newsize - h->tablelength);
for (i = 0; i < h->tablelength; i++) {
for (pE = &(newtable[i]), e = *pE; e != NULL; e = *pE) {
index = indexFor(newsize,e->h);
if (index == i)
{
pE = &(e->next);
}
else
{
*pE = e->next;
e->next = newtable[index];
newtable[index] = e;
}
}
}
}
h->tablelength = newsize;
h->loadlimit = (unsigned int) ceil(newsize * max_load_factor);
return -1;
@@ -140,13 +140,13 @@ hashtable_insert(struct hashtable *h, void *k, void *v)
unsigned int index;
struct entry *e;
if (++(h->entrycount) > h->loadlimit)
{
/* Ignore the return value. If expand fails, we should
* still try cramming just this value into the existing table
* -- we may not have memory for a larger table, but one more
* element may be ok. Next time we insert, we'll try expanding again.*/
hashtable_expand(h);
}
{
/* Ignore the return value. If expand fails, we should
* still try cramming just this value into the existing table
* -- we may not have memory for a larger table, but one more
* element may be ok. Next time we insert, we'll try expanding again.*/
hashtable_expand(h);
}
e = (struct entry *)malloc(sizeof(struct entry));
if (NULL == e) { --(h->entrycount); return 0; } /*oom*/
e->h = hash(h,k);
@@ -168,11 +168,11 @@ hashtable_search(struct hashtable *h, void *k)
index = indexFor(h->tablelength,hashvalue);
e = h->table[index];
while (NULL != e)
{
/* Check hash value to short circuit heavier comparison */
if ((hashvalue == e->h) && (h->eqfn(k, e->k))) return e->v;
e = e->next;
}
{
/* Check hash value to short circuit heavier comparison */
if ((hashvalue == e->h) && (h->eqfn(k, e->k))) return e->v;
e = e->next;
}
return NULL;
}
@@ -193,20 +193,20 @@ hashtable_remove(struct hashtable *h, void *k)
pE = &(h->table[index]);
e = *pE;
while (NULL != e)
{
/* Check hash value to short circuit heavier comparison */
if ((hashvalue == e->h) && (h->eqfn(k, e->k)))
{
*pE = e->next;
h->entrycount--;
v = e->v;
freekey(e->k);
free(e);
return v;
}
pE = &(e->next);
e = e->next;
}
{
/* Check hash value to short circuit heavier comparison */
if ((hashvalue == e->h) && (h->eqfn(k, e->k)))
{
*pE = e->next;
h->entrycount--;
v = e->v;
freekey(e->k);
free(e);
return v;
}
pE = &(e->next);
e = e->next;
}
return NULL;
}
@@ -261,4 +261,16 @@ hashtable_destroy(struct hashtable *h, int free_keys, int free_values)
* 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.
*/
*/
/* For Emacs:
* Local Variables:
* mode:c
* indent-tabs-mode:t
* tab-width:4
* c-basic-offset:4
* End:
* For VIM:
* vim:set softtabstop=4 shiftwidth=4 tabstop=4 expandtab:
*/