+/** @file hashtable.h
+ * @brief Hashtable. Standard chained bucket variety.
+ */
+
#ifndef HASHTABLE_H
#define HASHTABLE_H
struct hashlistnode<_Key,_Val> *next;
};
-template<typename _Key, typename _Val, typename _KeyInt, int _Shift>
+/** Hashtable class. By default it is snapshotting, but you can pass
+ in your own allocation functions. */
+
+template<typename _Key, typename _Val, typename _KeyInt, int _Shift=0, void * (* _malloc)(size_t)=malloc, void * (* _calloc)(size_t, size_t)=calloc, void (*_free)(void *)=free>
class HashTable {
public:
HashTable(unsigned int initialcapacity=1024, double factor=0.5) {
// Allocate space for the hash table
- table = (struct hashlistnode<_Key,_Val> **) calloc(initialcapacity, sizeof(struct hashlistnode<_Key,_Val> *));
+ table = (struct hashlistnode<_Key,_Val> **) _calloc(initialcapacity, sizeof(struct hashlistnode<_Key,_Val> *));
loadfactor = factor;
capacity = initialcapacity;
- threshold = initialcapacity*loadfactor;
+ threshold = (unsigned int) (initialcapacity*loadfactor);
mask = (capacity << _Shift)-1;
size = 0; // Initial number of elements in the hash
}
struct hashlistnode<_Key,_Val> * bin = table[i];
while(bin!=NULL) {
struct hashlistnode<_Key,_Val> * next=bin->next;
- free(bin);
+ delete bin;
bin=next;
}
}
- free(table);
+ _free(table);
+ }
+
+ void * operator new(size_t size) {
+ return _malloc(size);
+ }
+
+ void operator delete(void *p, size_t size) {
+ _free(p);
}
+ void * operator new[](size_t size) {
+ return _malloc(size);
+ }
+
+ void operator delete[](void *p, size_t size) {\
+ _free(p);
+ }
+
+ /** Reset the table to its initial state. */
void reset() {
for(int i=0;i<capacity;i++) {
struct hashlistnode<_Key,_Val> * bin = table[i];
while(bin!=NULL) {
struct hashlistnode<_Key,_Val> * next=bin->next;
- free(bin);
+ delete bin;
bin=next;
}
}
memset(table, 0, capacity*sizeof(struct hashlistnode<_Key, _Val> *));
size=0;
}
-
+
+ /** Put a key value pair into the table. */
void put(_Key key, _Val val) {
if(size > threshold) {
//Resize
unsigned int newsize = capacity << 1;
resize(newsize);
}
-
+
struct hashlistnode<_Key,_Val> *ptr = table[(((_KeyInt)key) & mask)>>_Shift];
size++;
struct hashlistnode<_Key,_Val> *search = ptr;
search=search->next;
}
- struct hashlistnode<_Key,_Val> *newptr=(struct hashlistnode<_Key,_Val> *)malloc(sizeof(struct hashlistnode<_Key,_Val>));
+ struct hashlistnode<_Key,_Val> *newptr=(struct hashlistnode<_Key,_Val> *)new struct hashlistnode<_Key,_Val>;
newptr->key=key;
newptr->val=val;
newptr->next=ptr;
table[(((_KeyInt)key)&mask)>>_Shift]=newptr;
}
+ /** Put a key entry into the table. */
+ _Val * ensureptr(_Key key) {
+ if(size > threshold) {
+ //Resize
+ unsigned int newsize = capacity << 1;
+ resize(newsize);
+ }
+
+ struct hashlistnode<_Key,_Val> *ptr = table[(((_KeyInt)key) & mask)>>_Shift];
+ size++;
+ struct hashlistnode<_Key,_Val> *search = ptr;
+
+ while(search!=NULL) {
+ if (search->key==key) {
+ return &search->val;
+ }
+ search=search->next;
+ }
+
+ struct hashlistnode<_Key,_Val> *newptr=(struct hashlistnode<_Key,_Val> *)new struct hashlistnode<_Key,_Val>;
+ newptr->key=key;
+ newptr->next=ptr;
+ table[(((_KeyInt)key)&mask)>>_Shift]=newptr;
+ return &newptr->val;
+ }
+
+ /** Lookup the corresponding value for the given key. */
_Val get(_Key key) {
struct hashlistnode<_Key,_Val> *search = table[(((_KeyInt)key) & mask)>>_Shift];
-
+
while(search!=NULL) {
if (search->key==key) {
return search->val;
return (_Val)0;
}
+ /** Lookup the corresponding value for the given key. */
+ _Val * getptr(_Key key) {
+ struct hashlistnode<_Key,_Val> *search = table[(((_KeyInt)key) & mask)>>_Shift];
+
+ while(search!=NULL) {
+ if (search->key==key) {
+ return & search->val;
+ }
+ search=search->next;
+ }
+ return (_Val *) NULL;
+ }
+
+ /** Check whether the table contains a value for the given key. */
bool contains(_Key key) {
struct hashlistnode<_Key,_Val> *search = table[(((_KeyInt)key) & mask)>>_Shift];
-
+
while(search!=NULL) {
if (search->key==key) {
return true;
}
return false;
}
-
+
+ /** Resize the table. */
void resize(unsigned int newsize) {
struct hashlistnode<_Key,_Val> ** oldtable = table;
struct hashlistnode<_Key,_Val> ** newtable;
unsigned int oldcapacity = capacity;
-
- if((newtable = (struct hashlistnode<_Key,_Val> **) calloc(newsize, sizeof(struct hashlistnode<_Key,_Val> *))) == NULL) {
+
+ if((newtable = (struct hashlistnode<_Key,_Val> **) _calloc(newsize, sizeof(struct hashlistnode<_Key,_Val> *))) == NULL) {
printf("Calloc error %s %d\n", __FILE__, __LINE__);
exit(-1);
}
-
+
table = newtable; //Update the global hashtable upon resize()
capacity = newsize;
- threshold = newsize * loadfactor;
+ threshold = (unsigned int) (newsize * loadfactor);
mask = (newsize << _Shift)-1;
-
+
for(unsigned int i = 0; i < oldcapacity; i++) {
struct hashlistnode<_Key, _Val> * bin = oldtable[i];
-
+
while(bin!=NULL) {
_Key key=bin->key;
struct hashlistnode<_Key, _Val> * next=bin->next;
-
+
unsigned int index = (((_KeyInt)key) & mask) >>_Shift;
struct hashlistnode<_Key, _Val> * tmp=newtable[index];
bin->next=tmp;
bin = next;
}
}
-
- free(oldtable); //Free the memory of the old hash table
+
+ _free(oldtable); //Free the memory of the old hash table
}
-
+
private:
struct hashlistnode<_Key,_Val> **table;
unsigned int capacity;
projects / model-checker.git / blobdiff