htop/Hashtable.c

172 lines
4.2 KiB
C

/*
htop - Hashtable.c
(C) 2004-2011 Hisham H. Muhammad
Released under the GNU GPL, see the COPYING file
in the source distribution for its full text.
*/
#include "Hashtable.h"
#include <stdlib.h>
#include <assert.h>
/*{
#include <stdbool.h>
typedef struct Hashtable_ Hashtable;
typedef void(*Hashtable_PairFunction)(int, void*, void*);
typedef struct HashtableItem {
unsigned int key;
void* value;
struct HashtableItem* next;
} HashtableItem;
struct Hashtable_ {
int size;
HashtableItem** buckets;
int items;
bool owner;
};
}*/
#ifdef DEBUG
static bool Hashtable_isConsistent(Hashtable* this) {
int items = 0;
for (int i = 0; i < this->size; i++) {
HashtableItem* bucket = this->buckets[i];
while (bucket) {
items++;
bucket = bucket->next;
}
}
return items == this->items;
}
int Hashtable_count(Hashtable* this) {
int items = 0;
for (int i = 0; i < this->size; i++) {
HashtableItem* bucket = this->buckets[i];
while (bucket) {
items++;
bucket = bucket->next;
}
}
assert(items == this->items);
return items;
}
#endif
static HashtableItem* HashtableItem_new(unsigned int key, void* value) {
HashtableItem* this;
this = malloc(sizeof(HashtableItem));
this->key = key;
this->value = value;
this->next = NULL;
return this;
}
Hashtable* Hashtable_new(int size, bool owner) {
Hashtable* this;
this = malloc(sizeof(Hashtable));
this->items = 0;
this->size = size;
this->buckets = (HashtableItem**) calloc(size, sizeof(HashtableItem*));
this->owner = owner;
assert(Hashtable_isConsistent(this));
return this;
}
void Hashtable_delete(Hashtable* this) {
assert(Hashtable_isConsistent(this));
for (int i = 0; i < this->size; i++) {
HashtableItem* walk = this->buckets[i];
while (walk != NULL) {
if (this->owner)
free(walk->value);
HashtableItem* savedWalk = walk;
walk = savedWalk->next;
free(savedWalk);
}
}
free(this->buckets);
free(this);
}
void Hashtable_put(Hashtable* this, unsigned int key, void* value) {
unsigned int index = key % this->size;
HashtableItem** bucketPtr = &(this->buckets[index]);
while (true)
if (*bucketPtr == NULL) {
*bucketPtr = HashtableItem_new(key, value);
this->items++;
break;
} else if ((*bucketPtr)->key == key) {
if (this->owner)
free((*bucketPtr)->value);
(*bucketPtr)->value = value;
break;
} else
bucketPtr = &((*bucketPtr)->next);
assert(Hashtable_isConsistent(this));
}
void* Hashtable_remove(Hashtable* this, unsigned int key) {
unsigned int index = key % this->size;
assert(Hashtable_isConsistent(this));
HashtableItem** bucket;
for (bucket = &(this->buckets[index]); *bucket; bucket = &((*bucket)->next) ) {
if ((*bucket)->key == key) {
void* value = (*bucket)->value;
HashtableItem* next = (*bucket)->next;
free(*bucket);
(*bucket) = next;
this->items--;
if (this->owner) {
free(value);
assert(Hashtable_isConsistent(this));
return NULL;
} else {
assert(Hashtable_isConsistent(this));
return value;
}
}
}
assert(Hashtable_isConsistent(this));
return NULL;
}
inline void* Hashtable_get(Hashtable* this, unsigned int key) {
unsigned int index = key % this->size;
HashtableItem* bucketPtr = this->buckets[index];
while (true) {
if (bucketPtr == NULL) {
assert(Hashtable_isConsistent(this));
return NULL;
} else if (bucketPtr->key == key) {
assert(Hashtable_isConsistent(this));
return bucketPtr->value;
} else
bucketPtr = bucketPtr->next;
}
}
void Hashtable_foreach(Hashtable* this, Hashtable_PairFunction f, void* userData) {
assert(Hashtable_isConsistent(this));
for (int i = 0; i < this->size; i++) {
HashtableItem* walk = this->buckets[i];
while (walk != NULL) {
f(walk->key, walk->value, userData);
walk = walk->next;
}
}
assert(Hashtable_isConsistent(this));
}