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/*
* Copyright (c) 2006 Dustin Sallings <dustin@spy.net>
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <assert.h>
#include "genhash.h"
#include "genhash_int.h"
/* Table of 32 primes by their distance from the nearest power of two */
static int prime_size_table[]={
3, 7, 13, 23, 47, 97, 193, 383, 769, 1531, 3067, 6143, 12289, 24571, 49157,
98299, 196613, 393209, 786433, 1572869, 3145721, 6291449, 12582917,
25165813, 50331653, 100663291, 201326611, 402653189, 805306357,
1610612741
};
static inline void*
dup_key(genhash_t *h, const void *key, size_t klen)
{
if (h->ops.dupKey != NULL) {
return h->ops.dupKey(key, klen);
} else {
return (void*)key;
}
}
static inline void*
dup_value(genhash_t *h, const void *value, size_t vlen)
{
if (h->ops.dupValue != NULL) {
return h->ops.dupValue(value, vlen);
} else {
return (void*)value;
}
}
static inline void
free_key(genhash_t *h, void *key)
{
if (h->ops.freeKey != NULL) {
h->ops.freeKey(key);
}
}
static inline void
free_value(genhash_t *h, void *value)
{
if (h->ops.freeValue != NULL) {
h->ops.freeValue(value);
}
}
static int
estimate_table_size(int est)
{
int rv=0;
size_t magn=0;
assert(est > 0);
magn=(int)log((double)est)/log(2);
magn--;
magn = ((int)magn < 0) ? 0 : magn;
assert(magn < (sizeof(prime_size_table) / sizeof(int)));
rv=prime_size_table[magn];
return rv;
}
genhash_t* genhash_init(int est, struct hash_ops ops)
{
genhash_t* rv=NULL;
int size=0;
if (est < 1) {
return NULL;
}
assert(ops.hashfunc != NULL);
assert(ops.hasheq != NULL);
assert((ops.dupKey != NULL && ops.freeKey != NULL) || ops.freeKey == NULL);
assert((ops.dupValue != NULL && ops.freeValue != NULL) || ops.freeValue == NULL);
size=estimate_table_size(est);
rv=calloc(1, sizeof(genhash_t)
+ (size * sizeof(struct genhash_entry_t *)));
assert(rv != NULL);
rv->size=size;
rv->ops=ops;
return rv;
}
void
genhash_free(genhash_t* h)
{
if(h != NULL) {
genhash_clear(h);
free(h);
}
}
void
genhash_store(genhash_t *h, const void* k, size_t klen,
const void* v, size_t vlen)
{
size_t n=0;
struct genhash_entry_t *p;
assert(h != NULL);
n=h->ops.hashfunc(k, klen) % h->size;
assert((int)n >= 0);
assert(n < h->size);
p=calloc(1, sizeof(struct genhash_entry_t));
assert(p);
p->key=dup_key(h, k, klen);
p->nkey = klen;
p->value=dup_value(h, v, vlen);
p->nvalue = vlen;
p->next=h->buckets[n];
h->buckets[n]=p;
}
static struct genhash_entry_t *
genhash_find_entry(genhash_t *h, const void* k, size_t klen)
{
size_t n=0;
struct genhash_entry_t *p;
assert(h != NULL);
n=h->ops.hashfunc(k, klen) % h->size;
assert((int)n >= 0);
assert(n < h->size);
p=h->buckets[n];
for(p=h->buckets[n]; p && !h->ops.hasheq(k, klen, p->key, p->nkey); p=p->next);
return p;
}
void*
genhash_find(genhash_t *h, const void* k, size_t klen)
{
struct genhash_entry_t *p;
void *rv=NULL;
p=genhash_find_entry(h, k, klen);
if(p) {
rv=p->value;
}
return rv;
}
enum update_type
genhash_update(genhash_t* h, const void* k, size_t klen,
const void* v, size_t vlen)
{
struct genhash_entry_t *p;
enum update_type rv=0;
p=genhash_find_entry(h, k, klen);
if(p) {
free_value(h, p->value);
p->value=dup_value(h, v, vlen);
rv=MODIFICATION;
} else {
genhash_store(h, k, klen, v, vlen);
rv=NEW;
}
return rv;
}
enum update_type
genhash_fun_update(genhash_t* h, const void* k, size_t klen,
void *(*upd)(const void *, const void *, size_t *, void *),
void (*fr)(void*),
void *arg,
const void *def, size_t deflen)
{
(void)deflen;
struct genhash_entry_t *p;
enum update_type rv=0;
size_t newSize = 0;
p=genhash_find_entry(h, k, klen);
if(p) {
void *newValue=upd(k, p->value, &newSize, arg);
free_value(h, p->value);
p->value=dup_value(h, newValue, newSize);
fr(newValue);
rv=MODIFICATION;
} else {
void *newValue=upd(k, def, &newSize, arg);
genhash_store(h, k, klen, newValue, newSize);
fr(newValue);
rv=NEW;
}
return rv;
}
static void
free_item(genhash_t *h, struct genhash_entry_t *i)
{
assert(i);
free_key(h, i->key);
free_value(h, i->value);
free(i);
}
int
genhash_delete(genhash_t* h, const void* k, size_t klen)
{
struct genhash_entry_t *deleteme=NULL;
size_t n=0;
int rv=0;
assert(h != NULL);
n=h->ops.hashfunc(k, klen) % h->size;
assert((int)n >= 0);
assert(n < h->size);
if(h->buckets[n] != NULL) {
/* Special case the first one */
if(h->ops.hasheq(h->buckets[n]->key, h->buckets[n]->nkey, k, klen)) {
deleteme=h->buckets[n];
h->buckets[n]=deleteme->next;
} else {
struct genhash_entry_t *p=NULL;
for(p=h->buckets[n]; deleteme==NULL && p->next != NULL; p=p->next) {
if(h->ops.hasheq(p->next->key, p->next->nkey, k, klen)) {
deleteme=p->next;
p->next=deleteme->next;
}
}
}
}
if(deleteme != NULL) {
free_item(h, deleteme);
rv++;
}
return rv;
}
int
genhash_delete_all(genhash_t* h, const void* k, size_t klen)
{
int rv=0;
while(genhash_delete(h, k, klen) == 1) {
rv++;
}
return rv;
}
void
genhash_iter(genhash_t* h,
void (*iterfunc)(const void* key, size_t nkey,
const void* val, size_t nval,
void *arg), void *arg)
{
size_t i=0;
struct genhash_entry_t *p=NULL;
assert(h != NULL);
for(i=0; i<h->size; i++) {
for(p=h->buckets[i]; p!=NULL; p=p->next) {
iterfunc(p->key, p->nkey, p->value, p->nvalue, arg);
}
}
}
int
genhash_clear(genhash_t *h)
{
size_t i = 0;
int rv = 0;
assert(h != NULL);
for(i = 0; i < h->size; i++) {
while(h->buckets[i]) {
struct genhash_entry_t *p = NULL;
p = h->buckets[i];
h->buckets[i] = p->next;
free_item(h, p);
}
}
return rv;
}
static void
count_entries(const void *key, size_t klen,
const void *val, size_t vlen, void *arg)
{
(void)key;
(void)klen;
(void)val;
(void)vlen;
int *count=(int *)arg;
(*count)++;
}
int
genhash_size(genhash_t* h) {
int rv=0;
assert(h != NULL);
genhash_iter(h, count_entries, &rv);
return rv;
}
int
genhash_size_for_key(genhash_t* h, const void* k, size_t klen)
{
int rv=0;
assert(h != NULL);
genhash_iter_key(h, k, klen, count_entries, &rv);
return rv;
}
void
genhash_iter_key(genhash_t* h, const void* key, size_t klen,
void (*iterfunc)(const void* key, size_t klen,
const void* val, size_t vlen,
void *arg), void *arg)
{
size_t n=0;
struct genhash_entry_t *p=NULL;
assert(h != NULL);
n=h->ops.hashfunc(key, klen) % h->size;
assert((int)n >= 0);
assert(n < h->size);
for(p=h->buckets[n]; p!=NULL; p=p->next) {
if(h->ops.hasheq(key, klen, p->key, p->nkey)) {
iterfunc(p->key, p->nkey, p->value, p->nvalue, arg);
}
}
}
int
genhash_string_hash(const void* p, size_t nkey)
{
int rv=5381;
size_t i=0;
char *str=(char *)p;
for(i=0; i < nkey; i++) {
rv = ((rv << 5) + rv) ^ str[i];
}
return rv;
}
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